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marylin monroe
Showing posts with label malondialdehyde. Show all posts
Showing posts with label malondialdehyde. Show all posts

Transfats the Last Bastion of the "Bad Fats"!? Two New Studies Shed Some Light onto Their Impact on Your Health.

Image 1: The Meet the Fats campaign is part of the stultification... ah I mean educational program of the American Heart Association
Meanwhile, even mainstream dietitians are beginning to understand that fats, which have been a, if not THE staple energy source in human history are not the bad boys the anti-fat hysteria of the 1980s would make us believe. Even the American Heart Association begins to advocate the use of "healthy fats" as part of a "heart healthy diet" - unfortunately, the AHA guys still lump Sat (that is the obese guy in the left) Trans (that is the sleazy guy in green) together, although the evidence against poor Sat (who obviously represents all saturated fats) is less conclusive than that against Poly, his money-grubbing sister who would do everything for her sponsors from the corn-industry... well, be that as it may, today's charge is against Trans who is accused of arson, or whole body inflammation, to be precise ;-)

New evidence against Trans is provided by two teams of experts, one from Europe (Bendson. 2011) and the Middle East (Dhibi. 2011). In what I personally would consider battery, Nathalie T. Bendson and her colleagues from Denmark and France assigned 52 (formerly ;-) healthy women randomly to receive
either 15.7g partially hydrogenated soybean oil or control oil without any industrially produced  trans fatty acids (IP-TFA) on a daily basis. The results were not life-threatening, but certainly not desirable:
After 16 weeks, IP-TFA intake increased baseline-adjusted serum tumor necrosis factor (TNF) by 12% more in the IP-TFA group compared with controls. Plasma soluble TNF receptors 1 and 2 were also increased by IP-TFA.
With TNF-alpha's role in the modulation of endothelial and vascular smooth muscle cell function as well as endothelial cell-blood cell interaction and "the importance of such alterations for vascular dysfunction, the initiation and progression of atherosclerosis" (Kleinbongard. 2010), Bendson et al.'s asssumption that
the IP-TFA-associated increase in cardiovascular risk beyond the adverse effect explained by changes in blood lipids may be partly due to induction of systemic low-grade inflammation
is possibly correct. Nevertheless, the jury is still out on how bad TNF-alpha actually is, as its role in cardiovascular disease is actually quite ambiguous with the aforementioned low-grade inflammation on the one hand and its ability to protect your heart by ischemic conditioning on the other hand.
Figure 1: Trans fat content of fresh soy oil, oxidized soy oi and margarine (data based on Dhibi. 2011).
More comprehensive evidence comes from a rodent study by Dhibi et al. who fed 48 male Wistar rats one out of four experimental diets which were either high in fat and included 20% fresh soybean oil diet (FSO), 20% oxidized soybean oil diet (OSO) and 20% margarine (MG) or based on the standard chow (control) with a protein/carbohydrate/fat ratio of 17/62/4 for 4 weeks (Dhibi. 2011). The liver function of the rats, as evidenced by the elevated transaminase levels (ALT, AST) and the increases in alkaline phosphatase (ALP) and lactate dehydrogensase (LDH) in figure 2, took a major beating.
Figure 2: Relative changes in transaminases (ALT, AST), alkaline phosphatase (ALP) and lactate dehydrogensase (LDH) in rats after 4 weeks on diets containing 20% fresh soybean oil, oxidized soybean oil or margarine (data calculated based on Dhibi. 2011)
I suppose the sponsors of the American Heart Association won't like this observation, but it is as plain as the nose in your face that even the "transfat free, heart-healthy polyunsaturated soybean oil" led to statistically significant increases in alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) levels... what, ah... of course that is because the diet was high in fat - how could I forget that 20% fat is still way too much and humans, just like rats should eat a 62% carb 4% fat diet ... I guess that was enough sarcasm for one blogpost, so let's back to the facts, now.
Figure 3: Correlation  between  fatty  acid  isomers  in  the  diet  and  oxidative  stress
  parameters in rat’s liver and plasma hepato-specific enzymes (data based on Dhibi. 2011).
The changes in liver function were accompanied by profound reduction in antioxidant enzyme activity (SOD: superoxide dismutase; GPx: glutathione peroxidase; CAT: catalase) and increased accumulation of conjugated dienes (CD) and malondialdehyde (MDA), the respective correlations of which with the fatty acids isomers (trans fats from mono-unsaturated and poly-unsaturated fatty acids, as well as total transfat content) are plotted in figure 3.

Image 2: Rat liver histology.
Due to its scale (only two different transfat profiles, i.e. oxidized soybean oil and margarine) the study's statistical power is yet so small that we can only make a definite case against the total transfat content for decreases in catalase activity and oxidized polyunsaturated fatty acids for the accumulation of conjugated dienes. With correlations in the the >0.5 and <-0.5 range for many other suspects and crimes, I will yet leave it up to you, the jury, to decide, which members of the transfat family (I suppose the American Heart Associations Trans character must have a whole bunch of children, then - just like in every honorable mafia family ;-) are to be held responsible for which of these crimes against health, the ultimate result of which you see in the histological changes in the livers of the rats fed with oxidized soy oil (OS) and margarine (MG)... So, members of the Jury, on the Case of Trans Fatty Acid (and his mafia clan) vs. the Suppversity, what you say?

Rodent Study Suggests: Selenium, Nature's Neuronal Corrosion Inhibitor Could Protect the Brains of Hard Training Athletes from Oxidative Damage.

Image 1: Selenium is a naturally occurring mineral
involved in a host of metabolic processes.
Are you a hard training athlete? A weekend warrior? Marathon runner? Or just an an average fitness-enthusiast? Yes? Did you ever think about what an exhausting workout, let alone arduous marathon running may do to your brain? No? Then it may come as a surprise to you that other than regular moderate physical exercise, which has repeatedly been shown to exert beneficial effects on mental and physical development, intense exercise precipitates oxidative stress not only in the working muscle groups, but within your whole body - including your brain, where the exercise-induced increase in free-radicals may dramatically increase lipid oxidation (Goldfarb.1996; Kanter. 1998).

Based on observations with other antioxidants and the well-established involvement of selenium in the activation of the master-antioxidant glutathion, researchers from the Selcuk University in Konya, Turkey, hypothesized that supplementation with yet to be determined amounts of selenium might ameliorate the detrimental effects of arduous exercise (Akil. 2011). To verify their hypothesis, the Akil et al. subjected a group of 4-6 month old Sprague-Dawley rats to one out of four treatments for 4 weeks:
  • group 1: unsupplemented sedentary control
  • group 2: selenium supplemented, sedentary control
  • group 3: swimming control (30 minutes in a closed glass-swimming pool; 50x50cm)
  • group 4: selenium supplemented + swimming (same as group 3)
Both, the animals in group 2 and group 4 were supplemented with additional  0.6mg/kg of selenium selenite per day. For an 80kg adult human being the human equivalent dose of 0.098mg or 90mcg per kilogram of body weight would amount to 7.8mg of additional selenium per day, a dose, of which textbook knowledge tells us that it is way beyond the upper-limit of 0.8mg/day. Yet, for the rats, this supposedly toxic amount of selenium turned out to be quite beneficial.
For more on the beneficial effects high doses of selenium may have and a short discussion of toxicity issues, see my previous post on "NAC + Zinc + Selen = Silver Bullett Against Mercury Poisoning"
As the data in figure 1 shows, the non-supplemented arduously exercising rats (group 3) had by far the highest malondialdehyde (MDA is an accepted marker of unwanted oxidation) levels. On the other hand, the MDA levels of the supplemented group were reduced by 11%. Compared to the sedentary controls, which had identical (i.e. within the statistical margin) MDA levels, the malondialdehyde content of their brains was still elevated by 57%. While selenium supplementation may thus have ameliorated the increase in brain MDA levels, it was not able to completely protect the rat-brains from free-radical induced oxidation processes.
Figure 1: Malondealdehyde (MDA) and glutathione levels in rat brains after 30 minutes of exhaustive swimming exercise (data adapted from Akil. 2011)
Interestingly, in both, the supplemented, as well as the non-supplemented exercise groups brain glutathion levels (GSH) increased by 124% and 71%, respectively - probably to protect the brain from extensive oxidation. Under this assumption the selenium induced increase in glutathione levels, which lead to a 53% greater GSH increase in the brains of the rats in the selenium supplemented swimming group, would adequately explain the lower MDA levels of the high selenium group.

While it would have been nice to see a comparison of the effects of different doses and exercise protocols, the study at hand is just another hint a the importance of a mineral, that was believed to be toxic up to the late 1950. Consequently, this is neither the first, nor will it be the last time you read about this extraordinary mineral on the SuppVersity - stay tuned for more!

Are Elevated Iron and Uric Acid Levels Too Much of a Price to Pay for a Creatine-Induced 11% Performance Increase?

Video 1 (GSSI): Notre Dame's Michael Floyd goes all out on the Wingate test (click to watch)
I guess you could say that these are the "classic days", here at the SuppVersity, contrary to my previous post on choline, which is - judged by the few people who still use it today, an "old school supplement" (cf. "Choline: Stronger, Faster, Leaner & More Muscular, or Just Another Dumb-and-Barbell Story?") - yesterday's post on caffeine highlighted the efficacy of a potent ergogenic aid and metabolic activator, with the effects of which most of us are so familiar that we are alway tempted to turn to useless crap like raspberry ketones, when what we are already doing is not only tried and proven, but based on respectable scientific data even more effective than the latest "innovation" from the snake oil industry. And let's be honest, haven't we all been tempted by one or another "new creatine", as well?

+11% peak performance in one week, solely from 5x4g of creatine per day!

A a matter of fact, creatine monhydrate does in fact share the same fate of being proven, but "boring" staple supplement and although that alone should be incentive enough to address the unquestionably outstanding +11% in anaerobic peak performance, +5% in continuous anaerobic performance and a +6% increase in total workload in a classic wingate anaerobic performance test speak, Barros et al. observed in a group of trained male subjects in response to a 7-day creatine loading protocol (20g creatine monohydrate, in 5 doses spread across the day, not glucose / sugar added; cf. Barros. 2012) After all, my gut tells me that the contemporary changes in the concentration of iron in the blood of the subjects in the the creatine arm of the study could revoke the mainstream-media fearmongerish hoopla over the purported dangers of the #1 natural ergogenic.
Figure 1: Basal iron, FRAP, malondialdehyde (MDA) and uric acid levels before and after 7-day supplementation with 5x4g of creatine monohydrate per day (based on Barros. 2012)
I mean, there is no debating, the level of iron in the blood of the creatine supplemented undergraduate students (age, 23.1 ± 5.8 years; height, 175.4 ± 2.3 cm; weight, 81.1 ± 9.3 kg) all of whom had been avid trainees for at least 6 months did increase by no less than 94.3%, while the subjects in the placebo group experienced a -21% reduction of these highly reactive molecules (Just as an aside, the decline in serum iron in the placebo group and the significant difference in baseline levels between the random groups, alone, render any implications at least questionable; I mean, wouldn't you expect the serum parameters to stay the same, when you do nothing extraordinary, aside from popping some sugar pills?).
Figure 2: Changes in wingate anaerobic performance (left) and exercise induced changes iron, FRAP, malondialdehyde (MDA) levels during the wingate test at the end of the supplementation period (based on Barros. 2012)
In conjunction with the likewise highly significant increase in uric acid levels, conventional (blogosphere-)wisdom, which constantly ignores the antioxidative nature of uric acid, which acts as efficient antioxidant and chelating agent for iron ions (Karlsson. 1997), limits the oxidation of polyunsaturated fatty acid in the erythrocyte membrane and prevents hemolysis (= the rupture of red blood cells) in vitro (Einsele. 1987), would suggest that taking creatine takes a close second to fructose on the list of the villains of the bad, bad "neolithic" century.
How dangerous is the creatine induced increase in iron?

Image 1 (Paramount Pictures): I guess, it must have been creatine monohydrate, then, that turned Robert Downey Jr. into Ironman ;-)
Now, despite the as of late publicly propagated concerns about increased iron levels and their potential causative role in the etiology of insulin resistance and diabesity (obesity + diabetes), recent scientific evidence suggests that "high iron", such as all previous scapegoats people like to hold liable, just to make sure not to admit that it is the sickening combination of laziness, convenience and unsound dietary advice that is at the heart of the current obesity epidemic.

Huang et al., for example, did observe a direct effect of iron overload on diabetes risk - the latter was however a result of hereditary hemochromatosis (a genetic defect in iron metabolism) in their 2011 rodent trial (Huang. 2011). Results from two more recent studies by Silva et al. also indicate that the metabolic disturbances lead to differential expressions of the proteins involved in the metabolism of iron and thus substantiate the associative (and not causative) nature of the relation between high iron / ferritin and the metabolic syndrome (Silva. 2011; Silva. 2012).
Iron not causative? So why does phlebotomy help, then? If you read my post on the recently published data from the first controlled human trial that investigated the effects of phlebotomy on markers of blood glucose management, you will be aware that the measures they took, e.g. the HOMA-IR, are not really appropriate to assess the effects of this particular treatment (cf. "Phlebotomy: Can You Bleed Yourself Healthy and Lean?"). Furthermore, it is only logical that the removal of some of this "highly inflammable stuff" from an inflamed body will provide health benefits, even if the latter was totally benign for someone who has a lot less inflammation going on.
What is even more important, though, is that the difference between exercise-induced increases in serum iron and diet and diabesity-related increases in the storage form of iron, ferritin, in the liver. This is particularly true in view of the fact that our understanding of the former, i.e. the exercise induced release of iron into the blood stream is more than limited (Roberts. 1989; Smith. 1994). What we do see in the Barros study, however, is that the overall effect of creatine is rather anti- than pro-oxidative, since the increase in overall antioxidative capacity (as indicated by the changes in the iron-specific FRAP essay; cf. figure 1) did not just...
  • negate the potential negative effects of increased basal iron levels (see lowered baseline MDA levels post supplementation in figure 1), it also 
  • countered the exercise-induced lipid oxidation during the 2nd wingate test (as indicated by lower MDA levels; cf. figure 2). 
Eventually, the scientists say, the increase in antioxidant activity that is brought about by the ingestion of 20g/day creatine irrespective of whether you exercise or not could actually yield "general health benefits" (Barrios. 2012); and I would like to add that evidence for Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis, recovery from ischemia and, guess what, diabetes already exists (Tarnopolsky. 2000;"Creatine Ameliorates Type II Diabetes")! Certainly not bad for one of those bodybuilding supplements, "anabolics" or "gateway drugs", as creatine is often mislabeled , when a 100% clueless "journalist" tries to get the attention of his editor-in-chief, wouldn't you agree?

Suggested readings (some also mentioned in the text):
References:
  1. Barros MP, Ganini D, Lorenço-Lima L, Soares CO, Pereira B, Bechara EJ, Silveira LR, Curi R, Souza-Junior TP. Effects of acute creatine supplementation on iron homeostasis and uric acid-based antioxidant capacity of plasma after wingate test. J Int Soc Sports Nutr. 2012 Jun 12;9(1):25. 
  2. Huang J, Jones D, Luo B, Sanderson M, Soto J, Abel ED, Cooksey RC, McClain DA. Iron overload and diabetes risk: a shift from glucose to Fatty Acid oxidation and increased hepatic glucose production in a mouse model of hereditary hemochromatosis. Diabetes. 2011 Jan;60(1):80-7.
  3. Orozco MN, Solomons NW, Schümann K, Friel JK. Response of urinary biomarkers of systemic oxidation to oral iron supplementation in healthy men. Food Nutr Bull. 2012 Mar;33(1):53-62. 
  4. Roberts D, Smith DJ. Effects of high-intensity exercise on serum iron and α1-antitrypsin in trained and untrained men. Clin Sports Med 1989, 1:63–71.
  5. Silva M, Bonomo Lde F, Oliveira Rde P, Geraldo de Lima W, Silva ME, Pedrosa ML. Effects of the interaction of diabetes and iron supplementation on hepatic and pancreatic tissues, oxidative stress markers, and liver peroxisome proliferator-activated receptor-α expression. J Clin Biochem Nutr. 2011 Sep;49(2):102-8.
  6. Silva M, de Brito Magalhães CL, de Paula Oliveira R, Silva ME, Pedrosa ML. Differential expression of iron metabolism proteins in diabetic and diabetic iron-supplemented rat liver. J Biochem Mol Toxicol. 2012 Mar;26(3):123-9. 
  7. Smith DJ, Roberts D. Effects of high volume and/or intense exercise on selected blood chemistry parameters. Clin Biochem 1994, 27:435–440.
  8. Tarnopolsky MA. Potential benefits of creatine monohydrate supplementation in the elderly. Curr Opin Clin Nutr Metab Care. 2000 Nov;3(6):497-502.