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Saturday, December 8, 2012

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

Posted by Unknown at 2:36 AM
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. 2012). 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. 2012).


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. 2012)
  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. 2012). 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 . 2012), 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. 2012 & Jacobs. 2012)
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. 2012 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. 2012 Nov 28.
    • Ruas et al. APGC-1aI soform Induced by Resistance Training Regulates Skeletal Muscle Hypertrophy. Cell, December 7, 2012; 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. 2012 Dec 5;104(23):1808-14.

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