Showing posts with label inflammation. Show all posts
Showing posts with label inflammation. Show all posts

Wednesday, December 25, 2013

Beyond Celiac: Study Sheds New Light on Obesogenic Effects of Gluten - Are PPARs & Bacteria Both Involved?

Cornflakes peanut butter cookies - guaranteed not gluten free ;-)
With Christmas Eve being over, and grandma's cookies, Christmas stollen, and all sorts of other stuff from the bakery in front of you (literally), Christmas Day may actually prove to be a way more "dangerous" than Christmas Eve - not just because of the total amount of calories, but also because of the low satiety effect of these sweet treats.

A recent paper by scientists from the Universidade Federal de Minas Gerais in Belo Horizonte in Brazil does now point to another reason you better give those bakery products a wide berth - not just, but especially with the energy overshoot on Christmas day: Gluten!

Study confirms for the first time what scientists and laymen alike have been speculating about

In what the scientists claim is the first well-controlled study of the effects of gluten intake on metabolic health in a non-celiac, but Western-style diet scenario, Fabíola Lacerda Pires Soares and her colleagues put two groups of C57BL/6 mice on identical, iso-caloric high fat (hypercaloric) diets that differed only in terms of the amount of gluten that was added to the chow (0% gluten vs. 4.5% gluten).

Interestingly, the gluten diet did not influence any of the usual suspects, like food intake, total fat-free mass, fecal lipids excretion, blood lipid profile, blood total protein and ectopic (liver and muscle) lipid concentration (if you look closely you will realize that the gluten-free group actually had higher TRIGs, although the difference did not reach statistical significance).
Figure 1: Usual suspects and closer look at the effects 8 weeks gluten supplemented vs. gluten-free diets had on serum markers of metabolic syndrome and visceral fat parameters (Soares. 2013)
The data in figure 1 (right) does yet also show that the gluten content of the diet did nevertheless have a significant impact on the total body mass, visceral fat mass, lipid content and most importantly the adipocyte size.
Figure 2: Absolute adipokine levels (left) and fasting glucose and insulin levels, as well as Homa-IR (Soares. 2013)
Add to that the blunted expression of the anti-inflammatory and anti-diabetic fat hormone adiponectin and the increased the >5x higher expression of leptin (figure 2). And mix that with the reduced expression of PPAR-alpha and gamma of which Soares et al. argue that they may well be the key factor in the detrimental modulatory effect the addition of gluten had on the visceral fat structure and the lowered expression of the fat liberating enzymes LPL and and HSL, as well as reduced levels of the fat burning proteins ACC and CPT-1 (figure 3).
Figure 3: PPAR-alpha, -gamma, LPL, HSL, ACC and CPT-1 expression compared to rodents on regular chow (left); crown like structures in stained slices from visceral fat, inflammatory markers TNF-alpha and IL-6 (Soares. 2013)
So, even if the initially mentioned blood markers (aka the usual suspects) would suggest that both the gluten-consuming and gluten-free rodents were similarly bad off, the profound difference in inflammatory markers within the adipose tissue and the presence of comparatively many necrotic and inflammatory adipocytes in the crown like structures stand in line with increases in HOMA-IR, fasting glucose and insulin and an already compromised glucose clearance which are well-known harbingers of the metabolic syndrome.

These observations do not simply shed a whole new light on a hitherto largely ignored contributer to the etiology of the metabolic syndrome, they do also show that one of the reasons it has not been identified before is an over-reliance on BMI, total fat mass and serum lipids in the early stages of diabesity.

Reardless of whether the gut microbiome is part of the mechanism by which gluten predisposes the development of metabolic syndrome. Eating more inulin- and beta-glucan rich foods like Jerusalem artichokes, agave, bananas, onion, steel cut oats, wild yams, yacon, etc. certainly won't hurt your efforts to get lean, stay lean and leave the role of the obese diabetic to the other (read more)
Bottom line: The study at hand provides a good reason to limit your intake of "healthy whole grains" and other gluten containing foods, regardless of whether you suffer from celiac or not. Whether the established detrimental effects of gluten on the integrity of the intestinal wall and the increased leakage of bacterially produced endotoxins from the highly unfavorably changes in the gut microbiome in response to the high fat diets (Hildebrandt. 2009) are part of, or even the primary cause of these observations still has to be elucidated. The same goes for strategies to counter the translocation of the endotoxins across the gut lining (cf. "Shedding some light on the leaky gut") and the dose response relationship between the total amount of gluten in your diet and its effects on your metabolism. With 7% of pure gluten, it goes without saying that you would basically have to live of wheat in order to get to anywhere similar amounts of gluten in the diet... that said: Is it possible that the effects occur only in the presence of the high fat diet? After all, this alone has been shown to favor a pro-inflammatory gut microbiome.

You see there are enough questions to be answered in 2013 and the SuppVersity is going to be the place you will read the respective answers first ;-)

References:
  • Hildebrandt MA, Hoffmann C, Sherrill-Mix SA, Keilbaugh SA, Hamady M, Chen YY, Knight R, Ahima RS, Bushman F, Wu GD. High-fat diet determines the composition of the murine gut microbiome independently of obesity. Gastroenterology. 2009 Nov;137(5):1716-24.e1-2.
  • Soares FL, de Oliveira Matoso R, Teixeira LG, Menezes Z, Pereira SS, Alves AC, Batista NV, de Faria AM, Cara DC, Ferreira AV, Alvarez-Leite JI. Gluten-free diet reduces adiposity, inflammation and insulin resistance associated with the induction of PPAR-alpha and PPAR-gamma expression. J Nutr Biochem. 2013 Dec 17.

Monday, December 9, 2013

The IGF-1 Promoting, Myostatin Reducing, Muscle Building Effects of PGC-1 α-4: What It Does and Why Doing Cardio Before Weights Appears to Promote It's Expression

Warning: Reading this article won't make you look like Phil Heath over night.
As announced yesterday, I am about to get back to the study on PGC-1 alpha-4, the protein Carl Lanore and I talked about in the last installment of the SuppVersity Science Round-Up on Thursday. Since I am not going to simply repeat everything I already said during the show here, I suggest you download the podcast and listen to it before you read this article. Thus you would have a basic understanding of what the Ruas' study is all about and can class the additional information this article is going to provide with the stuff you've heard on Super Human Radio. If you don't have the time or are just sitting in the office, where listening to a radio show is not really an option, I would guess that those of you who have been around on the SuppVersity for some time now, should be able to connect the dots on their own.

PGC-1 alpha-4 the missing link between myostatin, IGF-1, hypertrophy and strength gains

With the combination of in-vitro and in-vivo data from rodents and humans the study Roas et al. published in the latest issue of Cell is a seam of information - literally. Actually, this is part of the reason, why I decided to restrict the following discussion to a summary of those findings that are either of general interest or can serve as a rational foundation for practically relevant conclusions, instead of simply reiterating the whole protocol.
  • Figure 1: Fluorescencemicroscopy analysis of myotubes expressing GFP alone or together with PGC-1 a1 or PGC-1 a4 (left) and effects on the expression of selected RNAs (Roa. 2013)
    PGC-1 alpha and its splice variants - The four known splice variants (alpha 1-4) the scientists tested for are expressed in most of the major organs of our body. Of particular interest for our discussion here are alpha-1 and alpha-4, with the former influencing 2002 and the latter controlling 519 gene function. The overlap between the two (98 genes) is actually pretty small, so that their downstream metabolic effects can be expected to be about as distinct as their underlying triggering mechanisms.

    While the energy sensing system appears to be responsible for the expression of PGC-1 alpha-1 (learn more about AMPK and how your body controls glucose uptake mitochondrial activity of the cells etc. depending on the local availability of energy), PGC-1 alpha 4 expression in skeletal muscle and thus the downstream effects on myostatin (inhibition) and IGF-1 (promotion) appear to be controlled by (contractile, but also metabolic) stress. Whether this is actually the case and in how far certain overlaps do exist will yet still have to be evaluated in future studies.

    Figure 2: Training or overtraining - good or bad inflammation; it's often difficult to hit the sweet spot (background adapted from Kramer. 2007)
    The same goes for the exact involvement of MAPK and other stress-sensors in our bodies and the dose-response relationship between the ROS and exercise induced expression of inflammatory factors such as IL-6 => NF-KappaB and their short term beneficial effects on the training induced adaptation processes (see figure 2). What can be said for sure, though, is that over-training and the downward spiral on the right side of  figure 2 is way more likely to be the underlying cause of suboptimal results, than an absence of adequate training stimuli on the left. Adequate recovery (primarily via rest + food and not by popping supplements or suppressing your well-deserved drowsiness with stims) is therefore about as, if not more important than the one additional rep you may or may not be able crank out at the end of an intense workout.
  •  What exactly can PGC-1 alpha 4 do? The trends in RNA expression in figure 1 do actually give you an idea of what the ensuing effects should be, but I guess some actual data will make it even more obvious what all these gene essays mean.
    Figure 3: Effect of injected PGC-1 a  and DNA manipulation on muscle fiber composition and overall muscularity and phenotype of the rodents (Ruas. 2013)
    As the data in figure 3 goes to show, the effects of PGC-1 alpha 4 injections are almost identical to what you would see to a standardized hypertrophy training. And as you may remember from my dissertation on the podcast, the >17x increase in PGC-1 alpha 4 expression in response to reloading of a previously suspended hindlimb in the scientists' rodent model would confirm just that: PGC-1 alpha 4 is expressed in response to muscular overload (as it does obviously occur, when you have not moved your leg an inch for 10 days) and initiates adaptation processes that are meant to strengthen and "build" the muscle to ensure that it is up to future challenges like this.

    Figure 4: Immunohistochemical analysis of gastrocnemius muscle from wild-type (WT) and Myo-PGC-1 a4 animals
    Due to the fact that the effects Roas et al. observed were muscle fiber specific and quasi non-existent in muscles that are predominantly slow twitch fibers (e.g. soleus or planatris), the concomittant boost in MHCIIa and MHCIIx myosin heavy chain types you see in figure 4 may easily be misinterpreted as a "transformation" of muscle fibers. If you look closely at the immunohistochemical analysis of the gastrocnemius muscle from wild-type (WT) and Myo-PGC-1 a4 animals in figure 4 the pictures do yet speak a very different language. If anything, the amount of the very fast twitch glycolytic (only) type IIb fibers may have dimished ever so slightly. The amount of slow twitch oxidative muscle fibers, on the other hand, remained constant, while the number of both MHCIIa and MHCIIx positive myofibers increased (the same happens, as you should remember from the Intermittent Thoughts in bodybuilders and recreational trainees, as well).
     
  • PGC-1 alpha 4 boosting agents include clenbuterol 5x (see Friday's "SuppVersity Science Round-Up Seconds"), forskolin 25x (both in vitro) and cold exposure (4°C) in rodent (!) brown adipose tissue.
Aside from the anti-cancer cachexia effect which is not directly related to the topic of this post, the previous paragraphs and the podcast should actually give you the most important information about this recently discovered splice variant of PGC-1 alpha, so that we can now segue into the "real-world" part of the study and take a closer look at the interactions with strength and cardio training I have been talking about on Thursday, as well.

Exercise and PGC-1 alpha 4 in real human beings

You cannot tell me that you have never heard of the notion that doing cardio not after but either before or or in-between your lifts an have its merit. If you can't remember it anyway, go back and reread "Before, After or In-Between? Study Puts Another '?' Behind the Widely Accepted 'Cardio After Weights' Paradigm."
Previous research associated PGC-1 alpha increases primarily with endurance training and, albeit to a lesser degree, glycogen depleting high intensity interval training (HIIT), or high volume resistance training. Over the years all of these training forms have been shown to contribute to mitochondrial biogenesis, a repartitioning of fiber types towards a more versatile oxidative myosin heavy chain pattern (similar to what you see in figure 4), the AMPK mediated stimulation of fatty acid oxidation and glucose uptake, angiogenesis and the prevention of muscle atrophy (Arany. 2008). The discovery of this new splice variant of the PGC-1 alpha protein does not diminish the significance of any of these results, but it does make one thing pretty obvious: Building muscle, endurance and oxidative capacity (mytochondria) are not mutually exclusive processes and it is very likely that there is a strong overlap between the metabolic and mechanic triggering processes.

It does in fact look as if the PGC-1 alpha "family" stands, if you will, at the crossroads of the aforementioned pathways with the "classic" alpha 1 variety being triggered by AMPK (and maybe other nutrient sensors) and the alpha 4 variety responding to the exercise-specific increase in stress signals. The results of the 8-week human study, Roas et al. conducted does yet show that things are - once again - not as easy as it may seem. If you look at the three training groups the subjects (the researchers don't provide details about age or training status, but probably young untrained men) were randomly assigned to...
  • Figure 5: Mo & Thu and Tue & Fri workouts (top) and results of the analysis of the biopsies that have been taken 48h after the last training session (Roas. 2013)
    Endurance Training (ET): During week 1, participants completed 30 min of stationary cycling at 65% VO2 peak 3 days per week. During week 2, participants completed 45 min of stationary cycling at 65% VO2 peak 3 days per week. During week 3, participants completed 45 min of stationary cycling at 65% VO2 peak 5 days per week. During weeks 4-8, participants completed 60 min of stationary cycling at 65%VO2 peak 5 days per week. 
  • Resistance Training (RT): During week 1, participants were familiarized with resistance training program and practiced the movements with light weight during each of the four training sessions. During week 2, participants completed 2 sets of 8-10 repetitions to failure 4 days per week. During week 3, participants completed 3 sets of 8-10 repetitions to failure 4 days per week. During weeks 4-8, participants completed 4 sets of 8-10 repetitions to failure 4 days per week. Table S1 presents the full exercise program. 
  • Combined Training (CT): The progression of the ET was the same as that described for the ET group, except that the durations were half as long as the ET group (i.e., 30min versus 60min). The progression of the RT was the same as that described for the RT group, except that the number of lifts was less the RT group. 
... as well as the exact protocol they have been following (figure 5, top), you would probably not have expected that the combined training protocol would have an edge over the higher volume resistance training in terms of both PGF-1 alpha 4 expression, as well as the decreases in myostatingthe increases in IGF-1, and the effective mean strength gains on the leg press (+30% for both with a minimal, statistically non-significant edge for the combined regimen; not shown in figure 5).

Implications: Why doing "cardio" before a workout could be beneficial

Figure 6: Free fatty acid levels before depletion (S1) and before (S2) and after (S3) exercise trial, as well as PGC1-alpha and p-AMPK expression (Psilander. 2013)
In the absence of detailed information about the increases in muscle CSA and protein content, it may be a bit too early to formulate any implications, but since the question of "doing cardio before a workout" was at the heart of an interesting discussion some of you started in the comment area to Friday's installment of the Seconds, I want to pick up on that and present a couple of garbled thoughts and references that may explain why the combined training did produce greater increases in PGC-1 alpha-4, as well as more pronounced downstream effects on myostatin and IGF-1 than the "growth specific" strength training program.

Now, one of the beauties of having your own blog with 1020 individual posts is that you can often simply refer people to previous posts such as the one from which I just copied figure 6 into this article. In fact, the title "8x Increase in "Mitochondria Building" Protein PGC1-Alpha W/ Medium Intensity Exercise in Glycogen Depleted Elite(!) Cyclists" actually gives away most of the 'secret' that's probably behind the purported benefits of a combined training regimen: Glycogen depletion!

Can I do HIIT instead? Personally I don't see any reason why you could not replace the 30min of steady state exercise with 10-15 minutes of HIIT (including active rest), but you should be aware of the fact that this will be more taxing on your central nervous system and probably more likely to result in a decrease in exercise performance on the subsequent workout, than sitting on an ergometer cycling at 60% of your VO2max. If you feel that it works for you - fine, but don't complain if in a year from now you still don't look like Mr. Olympia ;-)
Now the Psilander study does show that glycogen depletion, which is essentially what will happen (at least to a certain degree) if you perform 30 min of cardio training at a non-exhausting, but still energy consuming pace of 60% of your VO2 max before a workout does work. Without differentiating the various iso-forms of PGC-1 alpha Psilander's 5x increase in PGC-1 does yet not tell us whether we are dealing with the "right form" of PGC here. After all, the Psilander protocol involved two endurance sessions, with the first being a depletion session that was conducted on the day before the actual test and the second being a HIIT-esque exercise test (go back to the original post for more details).  Fortunately, there are 2019 other articles on the SuppVersity so that I don't even have to refer you to a study I have not already written about to add another piece to the puzzle.

A blast from the past and a glimpse into the future

On Wednesday, October 31, 2013, I wrote about the results of a study by Lundberg et al.. Again a slightly different protocol, this time with "cardio" in the morning and strength training later in the day, yet the exact same benefits in terms of PGC-1 alpha (total) expression:
Figure 7: Selected markers of mitochondrial biogenesis and protein synthesis before during and 15, respectively 180min after the resistance training bout in the AE + RE and the RE only leg (a.u.; data adapted from Lundberg. 2013)
With the more pronounced drop in myostatin in the combined training group in the Lundberg study, the only thing we would still need to further support the practical value of the more recent results from the Roas study would be a concomitant increase in IGF-1, as we would expect it, if working out in a (partly) glycogen depleted state would actually be the reason for the increase in PGC-1 alpha 4 Roas observed in the subjects of his study. Now I could copy and paste another graph, but I guess it will be enough, when I refer you back to the detailed elaborations on the connection between IGF-1 and it's muscle-specific splice variants and exercise induced beneficial, since acute and hormetic inflammation in the "IGF, MGF & Inflammation" part of the Intermittent Thoughts on Building Muscle (click here for an overview).

Please keep in mind: Regardless of the fact that previous studies did not test for the PGC-1 alpha subtypes, we cannot ignore the existing evidence that PGC-1 is not mandatory for the beneficial effects of endurance exercise on mitochondrial biogenesis (e.g. Rowe. 2013) and should therefore not overestimate the importance of PGC1 alpha 4 as the "one and only" muscle builder. I have said that before, but I guess it's important to repeat it - this is another missing link it's just like mTOR, testosterone and whatever other magic bullets people will tell you about not exclusively responsible for increases in muscle mass, mitochondrial capacity and whatever else you may just be dreaming of.
If we now add a couple of additional findings to this intellectual brew, like ...
  • the 100% increase in the expression of the heat shock protein HSP72 in a glycogen depleted vs. normal leg during a workout (Febbraio. Feb 2002)
  • the 150% increase of intramuscular HSP72 in response to an infusion with low doses of interleukin-6 (Febbraio. Sep 2002)
  • the non-existant negative side effects of IL-6 on muscle glucose uptake in healthy individuals (Steensberg. 2003)
  • IL-6's importance as a regulator of glucose metabolism during exercise (Helge. 2003; Febbraio. 2004) and it's satellite cell proliferation promoting effects (McKay. 2009) 
  • the Dr. Jakyll and Mr. Hyde nature of inflammation, in general and IL-6 in particular on glucose uptake and fatty acid oxidation, when it comes to its local and temporary (=beneficial effects) vs. systemic and chronic (=detrimental effects) presence in our body (Fisman. 2010)
...we do actually arrive back at where we came from, namely the difference between training and overtraining in figure 2.

Bottom line - cardio pre-workout as an intensity technique: On the basis of these considerations you can think of doing cardio before a workout as an intensity technique that will increase the beneficial stress and thus the demand for greater adaptive responses. That the latter will go hand in hand with an increased propensity of overtraining, particularly if you are not willing to (A) supply your body with the nutrients it needs after the workout and (B) to rest for an adequate amount of time before you hit the gym again, is something of which I would appreciate if it wasn't something I had to repeat in each and every SuppVersity article, but since this is and will probably remain the #1 reason why people don't make progress physique- or performance-wise, it's still the most important take home message at least for those of you who are new to the site. I hope this did not ruin this allegedly pretty lengthy post for you and believe I am not promising too much, when I say that you are soon going to read more about this protein here - after all, it's almost certain that we are going to see follow-up studies in the months to come.

    References:
    • Arany, Z. PGC-1 coactivators and skeletal muscle adaptations in health and disease. Curr. Opin. Genet Dev; 2008: 426–434. 
    • Febbraio MA, Steensberg A, Walsh R, Koukoulas I, van Hall G, Saltin B, Pedersen BK. Reduced glycogen availability is associated with an elevation in HSP72 in contracting human skeletal muscle. J Physiol. 2002 Feb 1;538(Pt 3):911-7.
    • Febbraio MA, Steensberg A, Fischer CP, Keller C, Hiscock N, Pedersen BK. IL-6 activates HSP72 gene expression in human skeletal muscle. Biochem Biophys Res Commun. 2002 Sep 6;296(5):1264-6.
    • Febbraio MA, Hiscock N, Sacchetti M, Fischer CP, Pedersen BK. Interleukin-6 is a novel factor mediating glucose homeostasis during skeletal muscle contraction. Diabetes. 2004 Jul;53(7):1643-8.
    • Fisman EZ, Tenenbaum A. The ubiquitous interleukin-6: a time for reappraisal.
      Cardiovasc Diabetol. 2010 Oct 11;9:62.
    • Helge JW, Stallknecht B, Pedersen BK, Galbo H, Kiens B, Richter EA. The effect of graded exercise on IL-6 release and glucose uptake in human skeletal muscle. J Physiol. 2003 Jan 1;546(Pt 1):299-305.
    • Kramer HF, Goodyear LJ. Exercise, MAPK, and NF-kappaB signaling in skeletal muscle. J Appl Physiol. 2007 Jul;103(1):388-95.
    • McKay BR, De Lisio M, Johnston AP, O'Reilly CE, Phillips SM, Tarnopolsky MA, Parise G. Association of interleukin-6 signalling with the muscle stem cell response following muscle-lengthening contractions in humans. PLoS One. 2009 Jun 24;4(6):e6027.
    • Psilander N, Frank P,  Flockhart M, Sahlin K. Exercise with low glycogen increases PGC-1agene expression in human skeletal muscle. Eur J Appl Physiol. 02 Oct 2013 [ahead of print]
    • Rowe GC, El-Khoury R, Patten IS, Rustin P, Arany Z. PGC-1α is dispensable for exercise-induced mitochondrial biogenesis in skeletal muscle. PLoS One. 2013;7(7):e41817. Epub 2013 Jul 24.
    • Ruas et al. APGC-1aI soform Induced by Resistance Training Regulates Skeletal Muscle Hypertrophy. Cell, December 7, 2013; 151:1319–1331.
    • Steensberg A, Fischer CP, Sacchetti M, Keller C, Osada T, Schjerling P, van Hall G, Febbraio MA, Pedersen BK. Acute interleukin-6 administration does not impair muscle glucose uptake or whole-body glucose disposal in healthy humans. J Physiol. 2003 Apr 15;548(Pt 2):631-8. Epub 2003 Mar 14.

    Saturday, December 7, 2013

    Science Round-Up Seconds: PGC-1 Alpha 4 Unlocks Muscle Growth, Alpha Lipoic Acid & Dietary N-6 Overload, Aspirin & Other NSAIDs Your Liver & Overall Mortality

    Myotubes under the microscope - vehicle (top, normal size), clenbuterol (+100% protein content, middle), clenbuterol + PGC1a4 inhibition (+50% protein content, bottom)
    Actually I would hope that you have by now already listened to yesterday's installment of the SuppVersity Science Round-Up. If you did, you are one of a group of highly privileged trainees who already knows why not all PGC1-alpha is created equal and how the alpha-4 isoform does appear to be the missing link between myostatin, on the one hand, and IGF-1 on the other. If you have already listened to the show, you may also have noticed that I was pretty excited about the publication of the Ruas paper (Ruas. 2013). Firstly this study has almost everything you could expect from cutting edge science: A in-vitro tudy to elucidate the basic mechanisms, an in-vivo rodent study involving both wild-type and genetically modified mice and - much to my own surprise - an in-vivo exercise part. And secondly, the results provides the missing link I personally have been looking for, when I wrote the Intermittent Thoughts on Building Muscle Series (click here for the summary and overview of the individual parts) - the link between IGF-1 and myostatin and the reason working out will always make you stronger and bigger and not bigger and weaker, as it is the case in the poor myostatin-knockout mice. Ah... I almost forgot: Third- and lastly, the fact that the researchers induced their hypertrophy effects in a specific part of their study by administering clenbuterol, which then did what I have likewise written about before (see "The Clenbuterol Myostatin Connection"), which is decreasing the expression of myostatin and thus producing skeletal muscle hypertrophy, yet as we now know not directly, but rather in consequence to its PGC-1 a4 promoting effects (+400%!) and the respective downstream effects on myostatin, which were non-existent, when the scentsts blocked PGC-1 a4 expresson (see images on the right)... 

    I guess, you need to be somewhat geeky to find that exciting, but anyway. If you don't I'd still recommend you take a listen to the show - it's well worth it, even for totally normal exercise enthusiasts ;-)

    And now for the actual seconds

    Since the Ruas study appeared on my "radar" quasi in the last minute. We did not get to talk about several of the things I have announced and just to make sure you are not going to be disappointed, once you have gone through the following findings, I will address the acidity / alkalinity issue in a separate post in the future. It requires some more detailed elaborations - but the wait is going to be worth it ;-)

    ALA rescues the liver from toxic N-6 overload

    Actually this item would have fitted in pretty neatly with the things I explained about the different isoforms of PGC-1 alpha and how they appear to be regulated by diet / energy energy intake and expenditure via AMPK, on the one hand, and MAPKs, i.e. 'switches' that are triggered by stress, as the wear and tear of exercise, for example would be one. Now, we have already talked about the latter aspect, so that I guess I can get right to the not so novel, but still intriguing insights a  group of scientists from the Cerrahpaşa Medical Faculty Medical Biology Department at the Istanbul University  bring to the table as far as the former pathway is concerned (Kaya-Dagistanli. 2013).


    In their 8-week experiment, Kaya-Dagistanli and her colleagues confirmed two things, of which I don't even know what would be the more important result:
    Figure 1: Fibrosis and fatty degeneration scores in the control group (normal diet) and the high omega-6 group w/ and w/out ALA Kaya-Dagistanli. 2013)
    1. The administration of a diet that contained 60% fat from safflower oil, 20% kcal carbohydrate and 20% kcal protein (51% of the fat from n-6, n-6:n-3 ratio of 15.4) did produce major changes not only in the GSH levels, a measure of the total antioxidant capacity in the livers of the 24 Wistar rats, the relatively short time span was even enough to increase the fibrosis and fatty degenration scores by ~10x (see figure 1) compared to the rodents on the low fat standard chow in the control group (only 12% fat total, 39.1% n-6, n-6 : n-3 ratio of 9.3).
    2. The addition of 35 mg/kg DL-alpha lipoic acid (human equivalent: 5.7mg/kg; ~500mg/day) from week 4 to week 8 reduced both the negative effects of the omega-6 overload on GSH and the pathological degeneration of the liver, but could not fully restore it to normal levels.
    Not just in view of the fact that ALA could not totally blunt the detrimental effects of the n-6 diet, but also in view of the fact that rodents on the regular diet did not see any benefits (remember: if you are not fat and metabolically deranged ALA ain't necessary, probably counterproductive; "Lean & Muscular W/ alpha lipoic acid?"), I personally gravitate towards (1), as far as the more significant finding is concerned. After all, it goes to show you that you simply have to the absolute (and relative?) amount of omega-6 fatty acids in your diets and can go without any such supplements as high dose fish oil and/or alpha lipoic acid. Bottom line: Don't bang your head against the wall and you won't need a helmet ;-)

    NSAIDs liver cancer, chronic liver disease and other nasty ways to die

    It's quite a happy coincidence that the December issue of the Journal of the National Cancer Institute held yet another intriguing study on the potentially beneficial health effects of the use of NSAIDs, which had been addressed in August already, when Jacobs et al. have gotten quite some public attention with their paper on aspirin use and the decrease in all-cause mortality (Jacobs. 2013). The novel paper that's based on prospective data on 300,504 men and women aged 50 to 71 years who had participated in National Institutes of Health-AARP Diet and Health Study and has been written by a group of scientist who actually work at the National Cancer Institute (Sahasrabuddhe . 2013), did not deal with a slightly different research question, i.e. does the use of aspirin and other NSAIDs offer protection against liver cancer (hepatocellular carcinoma) and death due to chronic liver disease, it also offers a slightly more sophisticated analysis of the (a) the frequency of NSAID use and potential interactions. Still, I decided to summarize the main findings of both, also in view of the fact that we are dealing  wih different cohorts (study subjects in the Jacobs paper were 100,139 men and women with no history of cancer in the Cancer Prevention Study II Nutrition Cohort).
    Figure 2: Main results (hazard ratios) of two of the latest epidemiological studies into the effects of aspirin and other NSAIDs on liver cancer, death due to chronic liver disease (left) and aspirin alone on all cause mortality (right; data based on Sahasrabuddha. 2013 & Jacobs. 2013)
    With the "demarcation lines" being present at 1.0 (meaning normalized risk) it is pretty easy to see that at least with respect to liver health and all-cause-mortality and solely based on epidemiological evidence, aspirin appears to be one of those "miracle drugs" everyone can benefit from. We have to be cautious however, when we compare everyone with ourselves, after all - and pretty much stands out of question - the protective effects of aspirin and the slightly less unambiguous and as far as hepatic cancer goes, even detrimental effects of other NSAIDs are mediated by...
    • the modulation of inflammation via inhibition of the COX enzymatic pathways necessary for the synthesis of prostaglandins
    • the ensuing decreases in epithelial proliferation and angiogenesis, as well as an
    • increased apoptosis (regular cell death) and ameliorations in the inflammatory response and inflammatory cytokines via non-COX mediated pathways
    Now, if you remember the previous study about ALA and how useful it can be if you are the kind of person who hammer his head... ah, I mean who still has not gotten the message that the formerly hailed omega-6 PUFAs from the "healthy corn and vegetable oils" are not a bit healthy, on the one hand, and how superfluous (if not detrimental) the same supplement is for someone who does not exhibit exuberant inflammation to begin with, this certainly does put the results into perspective.



    Apropos perspective, I am not quite sure how you like the perspective that this is it, for today, but I would be pleased if you took that as an incentive to come back tomorrow and check out the next installment of SuppVersity On Short Notice and for the time being, I still have a couple of facebook news, I am sure you will enjoy:
    • Scientists from the UK and New Zealand do pretty damn good job pimping the sales of low fat products - learn what the press release does not tell you (read more)
    • German scientists find: Bisphenol A clogs calcium channels - don't know if you'd agree with them that the good news is that it appears to be reversible (read more)
    • Grazing is for fat cows, only  - women who want to be lean better eat like a human, i.e. three square meals not more that's it - this will also help with blood triglyceride management (read more
    • more, much more ;-) 
    Any you know, facebook is a fast media, so expect more news to be posted even before the official next SuppVersity article will hit the main site ;-)

      References:
      • Jacobs EJ, Newton CC, Gapstur SM, Thun MJ. Daily aspirin use and cancer mortality in a large US cohort. J Natl Cancer Inst. 2013 Aug 22;104(16):1208-17.
      • Kaya-Dagistanli F, Tanriverdi G, Altinok A, Ozyazgan S, Ozturk M. The effects of alpha lipoic acid on liver cells damages and apoptosis induced by polyunsaturated fatty acids. Food Chem Toxicol. 2013 Nov 28.
      • Ruas et al. APGC-1aI soform Induced by Resistance Training Regulates Skeletal Muscle Hypertrophy. Cell, December 7, 2013; 151:1319–1331. 
      • Sahasrabuddhe VV, Gunja MZ, Graubard BI, Trabert B, Schwartz LM, Park Y, Hollenbeck AR, Freedman ND, McGlynn KA. Nonsteroidal Anti-inflammatory Drug Use, Chronic Liver Disease, and Hepatocellular Carcinoma. J Natl Cancer Inst. 2013 Dec 5;104(23):1808-14.

        Wednesday, November 13, 2013

        Standard American Diet Has 'Optimal' Fatty Acid Ratio to Induce Diabesity. Plus: Study Shows Doubling Saturated Fats Would Yield More Benefits Than Halving Them

        Study confirms: The SAD diet yields 'optimal' results (img. forbes.com)
        Since this post is already lengthy enough, I will spare you how saturated fatty acids have long falsely been accused as the sole driving force of the western obesity epidemic and how the tides appear to be slowly yet steadily appear to be turning, as scientists delve deeper and deeper into the interactions of the total fat content in the diet, its fatty acid composition and the interaction of both with the two other macronutrients and their specific forms and get right to the study at hand. A study that appears in the current issue of the Journal of Lipid Science and deals with the first of the aforementioned interactions. The one that focuses on the total fat content and the individual fatty acid make-up of the diet (Enos. 2013).

        Fat shoot out: Saturated vs. mono vs. PUFA

        As Enos et al. point out, the main purpose of their study was to examine the effects of three high fat diets differing only with respect to the percentage of total calories from saturated fats.
        • SFA-6% - contained 6% saturated fats,
        • SFA-12% - contained 12% saturated fats, and
        • SFA-24% - contained 24% of saturated fats
        While the the high fat diets were set to have an identical fat (40% of the energy), carbohydrate (45% of the energy) and protein content, the two control diets were low in total fat (12%/68%/20% of the energy from fat/carbs/protein). They did however likewise differ as far as their fatty acid composition is concerned, with the modified chow mirroring the ratios (!) not the amounts of mono- and polyunsaturated fatty acids of the high fat chow (see figure 1).
        Figure 1: Fatty acid composition (left) and their sources (right) that were used in the different diets the rodents were fed for 16 weeks (based on Enos. 2013)
        The diets were administered for 16 weeks. Body composition and metabolism (glucose, insulin, triglycerides, LDL-C, HDL-C, total cholesterol) were examined monthly.  Adipose tissue (AT) expression of marker genes for M1 and M2 macrophages and inflammatory mediators (TLR-2, TLR-4, MCP-1, TNF-α, IL-6, IL-10, SOCS1, IFN-γ) was measured and so on and so forth... and the results were... well, not exactly as you may have expected (the latter statement assumes that you expected the SFA to be either the savior or the doom of the human race, depending on which side of the LC/LF divide you are stading).
        Figure 2: Body composition (left), adipocyte size (right) and fat pad weight (inset) of the rodents at the end of the study period (Enos. 2013) Values not sharing a common letter (abc) differ significantly over time within the given diet treatment (P≤.05)
        If you take closer look at the data in figure 2, there are two things that will probably catch your eye right away. The first 'eye catcher' pertains to the influence of replacing a large amount of the omega-6 fatty acids by monounsaturared fatty acids, as you will find them in olive oil, for example.
        • The rodents who received the modified standard chow, with a fatty acid composition identical to the high fat diets (SFA-6%, SFA-12%, SFA-24%) had the exact same body composition as their mates who received the standard chow with its 3.7x higher n6:n3 ratio. The removal of omega-6 fatty did thus not have any beneficial effects on adiposity in the low fat groups.
        The second 'eye catcher' is the non-linear increase in adiposity with increasing amounts of saturated fatty acids in the diets. This does not mean that the expected increase in obesity and adipocyte size was totally absent (read the latest "Get Lean & Stay Lean" item for more information about the association of large fat cells and metabolic syndrome), though:
        • The mice in the SF-6-24% did all gain significantly more body weight and body fat than their peers on the low fat diets, but there appears to be a turning point, when the saturated fat content exceeds 12%. After all the mice in the SFA-24% group had almost the same body composition as their peers on the SFA-6% diet.
        So, what do we make of these 'eye catchers'? The first one, you could argue, shows that "omega 6 overload" is not a problem, as long as you are consuming a low fat diet, in the first place. Even with the major part of those 12.2% of energy your diet provides in form of various fatty acids belonging to the potentially inflammatory omega-6 fatty acids, that's still way too low to do any harm. It does, by the way, yet explain why low fat diets work so well in a society, where most high fat foods the public consumes are laden with omega-6 fatty acids - not an insignificant result, I would say.

        The 12%-SF diet, most closely mimics the standard American diet

        Apropos public, the second 'eye catcher' is even more telling in term of public health,... wait, I should write sickness. Why? Well, the 12%SFA high fat diet, which supplies ...
        • 47% of energy in form of carbohydrates (380g sucrose, 100g maltodextrin, 50g cornstarch per 1kg of diet; identical for all SFA groups),
        • 40% of energy in form of fats (of which 12% were saturated fats), and
        • 13% of energy in form of protein (from casein),
        ... mimics, as the researchers point out, "most closely" (Enos. 2013) the standard American diet (SAD). And the result is obvious: Diabesity!

        It's a fat balancing act of macro and micro ratios  - complex and far from being understood 

        What's intriguing though, is that the adipogenic effects of the diet were ameliorated, when the SFA content was further increased and the diet contained 68.6g of lard per kg chow instead of just 35.4g and 96.7g of coconut oil instead of just 30g. Since this increase in SFA was at the expense of both mono- and omega-6 fatty acids, you could of course also argue that replacing at least the latter of the two with SFAs must be healthy. Unfortunately, even a brief glance back at figure 2 reveals that this is not necessarily correct. After all, the SFA-6% group was still better off than the SFA-24% group, although they had the highest amounts of oleic and omega-6 fatty acids in the diet.

        By now you should actually have realized that this is once more a difficult balancing act. Where different baseline intakes of dietary fat and carbohydrates (total) are pair of setscrews and the individiual fatty acid composition of the diet is another one. And the way these setscrews are set will not just influence the body composition:
        Figure 3: Serum IL-6, MCP-1, adiponectin and leptin levels, TNF-alpha mRNA expression in the adipose tissue (left), adipose tissue sample form the rodents receiving standard chow, the SFA-12% and the SFA-24% diet (Enos. 2013). The fat cells of the SFA-6% animals looked similar to those on the SFA-6% diets.
        Based on the body composition data presented in figure 2 the marked increases in serum leptin and TNF-alpha mRNA expression in the adipose tissue of the rodents in figure 3 (left) should be about as unsurprising as the fact that the adipocytes of the SFA-12% group show the greatest macrophage infiltration and subsequent necrotic tissue.

        If anything is surprising, it is the non-significance of the peak in IL-6 in the SFA-24% group (this was due to a very high standard deviation) and the fact that the serum level of MCP-1 a marker of increased macrophage activity was not elevated, while the adipose tissue mRNA expression was significantly higher (5-8x) in all SFA groups compared to both of the control diets. In the end this is yet only another clear sign that far more processes than we have previously thought happen locally and do not depend on circulating and thus endocrine signaling molecules.
        Figure 4: Blood glucose and insulin levels of the mice over the course of the study period (Enos. 2013)
        If you take the data from figure 4 into account as well, you will certainly agree with the statement Enos. et al. make pertaining to the negative effects of the SFA-12% diet, which is - just to remind you - the mirror image of the standard American diet:
        "The 12%-SF diet, most closely mimicking the standard American diet, led to the greatest adiposity (absolute fat mass), macrophage infiltration, and IR [insulin resistance]." (Enos. 2013)
        Figure 5: Total  cholesterol (TC, top) and LDL-C to HDL-C (bottom) ratios (Enos. 2013)
        And I guess it would actually be about time to get to the bottom line, here, if it was not for the sentence that follows this assertion:
        "Although the 24%-SF diet increased adiposity and produced IR, it did not significantly increase macrophage infiltration, it led to a lesser degree of AT inflammation, and it did not raise the TC/HDL-C ratio." (Enos. 2013)
        Yep, you are reading right, as the data in figure 5 shows the total to HDL ratio of the SFA-24% group, which were those rodents who consumed the largest amount of "bad" saturated fat, was virtually identical to the one of the rodents on the standard and the modified standard chow and significantly lower than in those rodents who 'lived the American way of life' (SFA-12%). A similar trend was seen in the LDL:HDL radio and the triglyceride levels.

        Bottom line: So, does that mean that we would just have to fry our potato chips in lard and all will be good? Not really, no. If we keep munching tons of plain sugar, even a saturated fat only diet is not going to save us from doom (I suspect there will be another inflection point at levels which exceed 50% SFA, anyway). What the study results do yet clearly implicate is that the macronutritent and fatty acid composition of the standard American diet is downright conspicuously obesogenic, pro-diabetic, inflammatory.

        While the macronutrient ratio (high carb + high fat) appears to set the body into fat storage mode, the individual ratios of the fatty acids determine the efficacy of body fat storage, the negative effects on blood glucose management, and the degree of adipose tissue inflammation - and the standard American diet excels in all these disciplines.

        As far as the saturated fats go (I wonder if it also plays a role that one of the main sources was coconut oil), the study suggests that you can achieve ameliorations of adiposity on both sides of the 'obesogenic optimum' of 12% saturated fats. If you take a last look at the data in figure 4, you will yet have to concede (or triumph?) that eating more not less saturated fat and thus frying your potatoes in lard, appears to be the more promising modification you could make, if the saturated fat content of the diet was your only set screw. Feels good to know it isn't right?

        References:
        • Enos RT, Davis JM, Velazquez KT, McClellan JL, Day SD, Carnevale KA, Murphy EA. Influence of Dietary Saturated Fat Content on Adiposity, Macrophage Behavior, Inflammation, and Metabolism: Composition Matters. J Lipid Res. 2013 Oct 28.

        Wednesday, November 6, 2013

        HMB Supplementation: Pre- or Pre- and Post-Workout? Anti- or Pro-Inflammatory? MA Thesis Offers Food for Thought

        Supplement facts: "Is as potent as the weak androgen Oxmethalone aka Anavar!" If that's how you advertise an expensive dietary supplement that tastes like poison, you better make sure your product delivers. For HMB the supplement companies must have overlooked that their clientele is in no way similar to the elderly subjects from their references with their protein deficient diets... the result? An epic fail for both the consumers who felt ripped off and the producers who probably expected this to be a long-term investment!
        HMB was once hailed to be as effective as a "weak" androgen such as Anavar. No wonder that dozens of consumers were pretty  disappointed, when they added it on top of their already protein and, at that times more or less coincidentally, leucine-laden diets and saw... nothing. Well, at least no gains that would even remotely remind anyone of Oxymetholone. With no costumer being interest to pay the extra bucks for the (at that time still) very expensive product, it was no wonder that the leucine metabolite β-Hydroxy β-methylbutyric acid (HMB) disappeared from the market relatively quickly.

        I bet, the fact that it tastes like poison did not really help either. after all it is downright impossible to add an effective amount of HMB into a powdered supplement, if you do not want to totally ruin the taste of the product.

        As a SuppVersity reader you will yet be aware that HMB is still no epic fail (read all older posts on HMB). Its marginal utility, however, is exactly that: Marginal -- at least when someone is taking it on top of tons of leucine rich protein powders, BCAAs and whatever else.

        HMB is not useless and there appears to be much we have to learn about it

        Despite the fact that it is very unlikely that taking HMB will turn you into a second Phil Health within weeks, its hitherto not fully understood beneficial effects on body fat, its effects on GH and IGF-1 as well as open questions that are related to our own bodies ability to produce HMB from leucine and whether this conversion mediated some of the benefits of the #1 among the BCAAs (=leucine) clearly indicate that there remains a lot to learn about Dr. Steven L. Nissen's 1996 discovery (Nissen. 1996).

        One of those things we still have... or I should say had to learn pertains the effect of HMB on the exercise induced expression of inflammatory cytokines, which turned out to be totally different from what Paul Raymond Vulcan, a student who has recently submitted his Master Thesis on the "Role of β-hydroxy-β-methylbutyrate (HMB) on inflammation after eccentric exercise" at the Iowa State University probably expected, when he recruited the 16 female and 16 male, untrained volunteers (mean age 3±0.30y, mean weight 67.5±0.9kg, and mean hight 172.2±0.7cm) for his study.

        'Extend your legs' till they burn ;-)

        The study consisted of a single exercise + supplementation trial in the course of which the participants underwent the following supplementation regimen:
        A note on the supplementation protocol: The way Volcan describes the protocol is at least "suboptimal". If I am getting it correctly (mostly by looking at a graphical outline) the participants in the pre/post trial received HMB not just on day 0, but also on day 1, day 2, day 3 and day 4 - always with lunch and dinner.
        "Experimental groups received supplement in one of the following manners: placebo pre- & post-exercise (CON), HMB pre-exercise (PRE) in either a calcium salt form or a free acid gel, HMB pre- & post-exercise (PRE/POST) in either a calcium salt form or a free acid gel.Supplements were given in a double-blind protocol so that investigators were also blind to the contents of the supplements throughout the study.  Originally, the study called for 5 treatment groups with a separation of calcium salt groups from the free acid gel groups. Due to sample sizes, groups receiving the same quantity of HMB were consolidated for statistical reasons." (Volcan. 2013)
        While it is certainly somewhat disappointing that we don't have a comparison of the salt and the gel variant of HMB (you will see the first gels hit the market, very soon, believe me),  this is understandable given the small sample size. What is yet a clear greenhorn mistake, however, is that Volcan does not disclose the amount of HMB salt the participants received. He states that the gel syringes contained 3ml but since I have no clue what else (besides HMB) is in the gel, I cannot tell you how much HMB the groups actually received (let alone calculate the equivalent in term of calcium-hmb).

        Standard protocol, surprising results

        Aside from this lapse the general protocol of the study looks pretty solid. The original challenge on day 0, which consisted of 3 sets of 50 eccentric leg extensions (both legs, 0° to 90°, 60°/sec; 3s per rep, 2 min rest between sets), was preceded and followed by a combination of
        • urine collection, 
        • muscle soreness test, 
        • leg circumference measurements, 
        • blood collection and a 
        • strength test
        which took place on day 0 (before the exercise protocol), 24h, 48h, 72h and 96h post. And I guess you could say "fortunately", the analysis of the respective data yielded not exactly what Volcan had expected. Firstly many expected effects did not occur (at least not if you consider only statistical significant inter-group effects), e.g. there were no differences for markers of muscle damage:
        • creatine kinase (CK) 
        • lactate dehydrogenase (LDH) and 
        • 3-methyl histidine (3-MH)
        Some did however show a trend (which did not reach statistical significance due to the small sample size) and / or did reach statistical significance at a certain time point only:
        • Figure 1: Peak performance force (in N) on the days after the leg extensions (based on Volcan. 2013). As you can see it's not like there had not been any effects, but with the small sample size few made it over the p < 0.05 hurdle, or put simply were "statistically significant".
          creatine kinase (CK) showed a non-statistically significant reduction in PRE/POST, while it was identical in PRE and CON (1593 IU compared to 3514 IU and 4068 IU; this is a candidate that would almost certainly have reached statistical significance with a larger number of participants, because the CK response shows high inter-individual variability)
        • the decrease in right leg peak force was about 16% in the CON group compared to 9% and 7% in the PRE and PRE/POST groups, respectively
        • the muscle soreness was also not significantly different between groups
        • the difference in the loss of peak force was only significant on day two when the peak performance in the control group dropped significantly (see figure 1)
        So far the somewhat disheartening but not actually novel part of the study. With the data in figure 2, however we are actually approaching the real news part of today's post:
        Figure 2: Makers of inflammation (IL-1 and TNF-alpha) after 3x50 leg extension on the test day, as well as 24h, 48h, 72h and 96h post (based on Vulcan. 2013)
        Take a close look and don't be fooled like I was, when I initially looked at the results and almost automatically assumed that there was a reduction in TNF-alpha and IL-1 in the group that recevived the most HMB (I must say I had only the poor black and white graphs from the original study and not the full-service pack you get, here at the SuppVersity, though ;-)

        "I mean, good things reduce inflammation, right?"

        Wrong, at least in the case of HMB, which certainly is a good thing, this is not the case. HMB does not reduce inflammation and that despite the fact that it works like a charm for those people of whom we are told that inflammation was the last thing they would need, namely the elderly. And still it appears as if the increased inflammatory response to the muscle damaging exercise on day 0 could actually be part of how HMB works. Volcan realizes that and states:
        Just in case you don't want to believe that inflammation could play a beneficial role in the regeneration and even the subsequent super-compensation process at the end of which both your muscle strength and muscle size will go up, I suggest you read the respective installment of the Intermittent Thoughts
        "The results of TNF-α and IL-1ra support the theory that inflammation is affected by HMB. In  both cases the CON group experienced a decline in serum concentration and the dip was reduced or limited by supplementation of HMB.  These results could be interpreted as an increase in the inflammatory response following HMB supplementation [...] This suggests that HMB creates a greater inflammatory response which may improve recovery of damaged tissue. When exactly this occurs and how, whether direct or indirect, is not evident from this study. We already kno that proteolysis is affected by HMB and it is also possible that inflammatory cytokines are mediating an optimal recovery." (my emphases in Volcan. 2013)
        Edited: While this sounds like an excellent hypothesis there is one thing Volcan has overlooked (and me too, at least initially, thus the update). The current scientific evidence suggest that the IL-1 receptor is like a multifaceted chimera. Or put simply, in its conventional form it will accept IL-1 and thus have exert pro-inflammatory downstream effects. IL-1-RA, which is the variant Volcan measured here, actually does the opposite, though: IL-1-RA blocks the inflammatory effects of IL-1 (Arend. 1997).

        In the end, this does not really change my previous assertion that "You need to go beyond the 'all inflammation is bad' paradigm and see 'inflammation', or what we usually refer to as inflammation as what it really is, namely a per se physiological reaction of our bodies that can be good, appropriate and highly desirable or bad, misplaced and highly detrimental depending on the circumstances." It just adds another level of complexity to that statement. And this added dimension can actually explain why HMB works in the elderly, but does not work (at least not to the same degree in young people). Old people have high IL-1 (the pro-inflammatory varieties), young and healthy people don't, so blocking IL-1 signaling will have more pronounced effect in the older ones of you than in the young chaps, who will probably fare quite well with nothing but a leucine rich protein shake.

        References:
        • Arend WP. Interleukin 1 receptor antagonist. A new member of the interleukin 1 family. J Clin Invest. 1991 Nov;88(5):1445-51.
        • Nissen SR, Sharp M, Ray JA, Rathmacher D, Rice JC, Fuller Jr, Connelly AS, Abumrad N: Effect of leucine metabolite beta -hydroxy-beta -methylbutyrate on muscle metabolism during resistance-exercise training. J Appl Physiol 1996, 81:2095-2104.
        • Volcan PR. Role of β-Hydroxy-β-methylbutyrate (HMB) on inflammation after eccentric exercise. Graduate Theses and Dissertations. 2013; paper 12501.

          Monday, October 21, 2013

          Vitamin A Educates T-Cells, Joins Forces With Vitamin D Against Liver Cancer. Milk Better Than Sugary Electrolyte Solutions for Rehydration? Helicobactor Pylori: Probiotics from Breast Milk & Feces Better Than Amoxicillin!

          Lactobacilli are hip, vitamin A is not - at the SuppVersity you still get news on both
          1kg! That's the amount of weight you could probably lose if you rid yourself of all the microbes in your gut - from the weight of the bacteria alone, of course. Whether this would be a good idea or not, is however very questionable. On the one hand, we do have the still not fully understood studies on obesity-resistant germ free mice and an accumulating amount of evidence that having the "wrong" bacteria in the gut is at least associated with an increased obesity risk (Blaut. 2013). On the other hand, however, we are seeing new studies on the various benefits of having the "right" gut microbiome being published on an almost daily basis. So what?

          Before we take a closer look at a definite benefit of having the "right" gut bacteria, though, let's start out with another likewise gut-related news item on the role of retinoic acid in T-cell education. In a way it's funny, it starts right where the bacteria reside, could have immune-modulatory effects that are way more pronounced and far reaching than probiotics and is still hardly discussed.

          Vitamin A is of critical importance to (intestinal) T-cell education

          If you have ever asked yourself how the immune cells in your body know what they are supposed to do, Catharine Ross' latest paper that was published in the American Journal of Clinical Nutrition and is based on a short talk the researcher from the Department of Nutritional Sciences at the Pennsylvania State University held at a conference earlier this year may provide at least some additional insides into the role a still way underrated molecule plays in this "T cell education" (Ross. 2013): Vitamin A!
          Figure 1: Model of T cell differentiation, from uncommitted naive T cells into different T cell subsets that produce different cytokines and thus promote different functional activities (adapted from Ross. 2013)
          As you can see in figure 1, retinoic acid does not simply promote the differentiation of regulatory T cells, which help to suppress inflammatory reactions, it also plays a significant role in normal mucosal immunity (in the gut, the airways and elsewhere) by modulating T cell activation and regulating cell trafficking. Moreover, vitamin A promotes antibody responses to T cell–dependent antigens. Needless to say that
          "[...] in a state of vitamin A deficiency, inflammatory T cell reactions may be inadequately opposed and therefore become dominant [...] Although data from human studies are still needed, the framework now developed from studies in mice and rat models suggests that adequate vitamin A status, [...] is  important for maintaining a proper balance of well-regulated T cell functions and for preventing excessive or prolonged inflammatory reactions." (Ross. 2013).
          Discovery a beta carotene derived vitamin A receptor blocker is only one of a couple of intriguing findings wrt to vitamin A.
          One thing that sticks out from the complex interactions (see figure 1), really is the way by which the interaction of vitamin A with the T-cells in the gut crucially determine the efficiency of the 'fist line defenses' and their downstream effects on the whole organism. It is by no means co-incidental that diarrhea is rampant in areas of the "third world", where a large amount of the population is vitamin A deficient (Beaton. 1994). And in fact studies have shown consitently that
          "RA is essential for 'imprinting' gut-homing specificity on T cells activated by intestinal DCs [dendritic cells] and suggested that MLN DCs are a source of RA that drives T cell differentiation toward the gut-homing phenotype" (Ross. 2013)
          Moreover, oral tolerance to foreign antigens and thus an allergy free live requires a form of immune suppression, which can be proffered or hampered by sufficient and insufficient vitamin A intakes. In that, the exact effects of vitamin A will depend on the cytokine milieu the T-cells are exposed to. Examples are...
          • an exaggerated IL-17 response with vitamin A deficiency, on the one hand, and
          • an increase of the inflammatory response due to high vitamin A in an IL-15 environment 
          Based on these observations, Ross rightly points out that "when RA is used for therapeutic purposes, it should be used cautiously in subjects with various inflammatory bowel conditions and sensitivities to dietary antigens." (Ross. 2013) People with gluten intolerance, celiac and other allergic reactions, for example would probably be better off avoiding the consumption of any form of supplemental vitamin A (on top of what's in their regular diet). Someone with high IL-17 and IL-6 levels as they have been observed in non-celiac inflammatory bowel disease, type 1 diabetes, multiple sclerosis and rheumatoid arthritis, on the other hand, could actually benefit from vitamin A's (especially ATRA) presence during activation of CD4+ T cells, because it will - even in the presence of IL-6 - "favor the development of the a Treg lineage at the expense of T cells secreting IL-17" and could thus help reduce chronic inflammation and keep autoimmune reactions at bay (Schambach. 2007; also Ramgolam. 2010).

          More news

          • Figure 2: Who cares about cell viability, the survival time (in days) matters
            Combination therapy with vitamin A and a vitamin D (not D3, but calcitriol) analog EB1089 kills liver cancer cells. And it does so more effectively than any of the two molecules alone. That's the actually unsurprising result of a study that has been conducted at the Beijing Army General Hospital in China. The researchers injected nude mice with molecules that made them develop hepatocellular cancer. Afterwards, the rodents received either 10 μmol/L retinoic acid (vitamin A), 10 nmol/L EB1089 or both as a combination treatment.

            Compared to vitamin A or the calcitriol analog alone, the combination treatmend resulted in a significanlty higher reduction of the viability of hepatocellular cancer cells. Based on TUNEL analysis, Zhang et al. did also establish that individual cancer cells had a higher apoptotic ratio in the combined drug group than in the groups for which the drugs were used separately. Most importantly, however, the tumor weight was decreased and the mice on the combination treatment lived significantly longer (see figure 2; Zhang. 2013)
          • In the same publication, Pritchett and Pritchett recommend 1.0-1.5ml / kg body weight per hour of chocolate milk as the optimal post-workout drink to be consumed in the 2 h after a workout.
            Skimmed milk, the ideal post-workout rehydration formula? According to L James' paper in Lamprecht's compendium Acute Topics in Sport Nutrition, milk is a way better choice then the standard sugar + electrolyte rehydration formulas. Interestingly this is not due to the minerals in the milk, or the sugar, but, as James argues, a direct consequence of the milk proteins, which help restore "fluid balance after exercise-induced dehydration to a greater extent than a carbohydrate-electrolyte sports drink." As James points out it will yet have to be elucidated, whether the simple addition of whey protein to a standard sugar + electrolyte formula would exert similar effects (James. 2013).
          • Probiotics to kill Helicobacter Pylori? While not every bacteria stands a chance against the nasty gut bug H. Pylori, certain Lactobacillus spp. strains obviously do. At least, if the results of a recent in-vitro + in vivo rodent study by Pei-Shan Hsieh can be replicated in human studies.
            Figure 3: Urease activity in H. pylpori after co-incubation with the specific probiotic and resulting bacteriostatic ratio (100% = bacteria free; data adapted from Hsieh. 2013)
            Lactobacillus acidophilus TYCA08, L. acidophilus TYCA15, L. johnsonii MH-68, and L. salivarius subsp. salicinius AP-32 were the most effective strains the researchers from National Chung Hsing University in Taichung, Taiwan, analyzed. And believe it or not, the latter of these, i.e. L. johnsonii MH-68, and L. salivarius subsp. salicinius AP-32, both of which are  by the way found in feces, were even minimally more potent effective than Amoxicillin, a moderate-spectrum, bacteriolytic, β-lactam antibiotic used to treat bacterial infections. L. acidophilus TYCA15, however, steals the show. This probiotic that occurs naturally in breast milk reduced the urease activity of H. Pylori by -97.1% (see figure 3).

            In the consecutive rodent study, Hseieh et al. did yet still use 109 CFU/mL of either AP-32 alone, MH-68 alone, or an equal mix of cultures of the two strains and both, "either alone or as a mixture in powder form were effective in reducing H. pylori load in gastric mucosa and help in reducing gastric inflammation and in regulation of gastric acid production." (Hsieh. 2013)
          Thats it for today and for this weekend. As mentioned yesterday, there was simply not enough time to do the necessary research for the follow up to the Athlete Triad Series, so that this will have to wait. So don't dig an even deeper whole in the mean time. Maybe you want to do some of the psychomotor tests mentioned in yesterday's news, and check whether you are already overtrained!? How steady are your hands, for example? And whatever the result may be, don't forget to enjoy the rest of the weekend!

          References:
          • Beaton GH, Martorell R, Aronson KA, Edmonston B. McCabe, G, Ross, AC, Harvey, B. Vitamin A supplementation and child morbidity and mortality in developing countries. Food Nutr Bull 1994;15(4): 282–9.
          • Blaut M, Klaus S. Intestinal microbiota and obesity. Handb Exp Pharmacol. 2013;(209):251-73.
          • Hsieh PS, Tsai YC, Chen YC, Teh SF, Ou CM, King VA. Eradication of Helicobacter pylori Infection by the Probiotic Strains Lactobacillus johnsonii MH-68 and L. salivarius ssp. salicinius AP-32. Helicobacter. 2013 Dec;17(6):466-77.
          • James L. Milk Protein and the Restoration of Fluid Balance after Exercise. In Lamprecht M (ed): Acute Topics in Sport Nutrition. Med Sport Sci. Basel, Karger, 2013, vol 59, pp 120–126. 
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