PharmacoNutrition Reviewed

Today’s post is a supplement to the list of recent papers on telomeres/telomerase Chris summarized over at Ouroboros a few days ago.

The article by Perez-Rivero et al. deals with the consequences of telomerase deficiency. Although aging as a parameter has not been assessed the outcome of the study sheds further light on the importance of telomerase in cell physiology, especially the regulation of oxidative stress:

“Comparison with wild type (WT) mouse emryonic fibroblasts (MEF) showed that mice lacking telomerase activity (Terc-/-) MEF had greater oxidant damage, showing higher superoxide anion and hydrogen peroxide production and lower catalase activity. Restoration of telomerase activity in Terc-/- MEF increased catalase expression and activity. TGF-β1 and collagen type IV levels were higher in Terc-/- than in WT MEF. TGF-β1 promoter activity decreased when Terc-/- MEF were incubated with exogenous catalase, suggesting that catalase deficiency is the cause of the TGF-β1 increase. Similar results were obtained in vivo.”

The latest issue of PNAS contains a collection of more than a dozen articles on reactive oxygen species (ROS):

“(…) The contents of this Special Feature on Reactive Oxygen Species in Chemistry and Biology represents a sampling of the excellent work that is being carried out at this important interface of chemistry and biology by using a wide range of chemical, kinetic, spectroscopic, and biological approaches. The authors come from several different fields and use a wide diversity of techniques and experimental systems; nevertheless, their studies all relate to the fundamental chemical reactivity of dioxygen and species derived from it.”
  

Source: Neurobiology of Aging (2007), in press
Article Type: Original Research
Authors: A Bender et al.

Image taken from: http://www.scienceinafrica.co.za/pics/06_2004/brain.jpg

Creatine (an amino acid derivative) is a widely used food supplement due to its putative ergogenic, i.e. exercise capacity enhancing, effect. In terms of exercise performance, a recent review by Paddon-Jones and colleagues (J. Nutr. 134) concludes that creatine is suggested to be of benefit to exercise lasting 30 seconds or less; in contrast, no direct effect of creatine supplementation on muscle protein synthesis has been found. Nonetheless, creatine sales still reached US$ 220 million in 2005.
So whereas creatine might do rather little to improve exercise performance, it still seems to improve health. And not only this, but also survival – at least in mice. Based on previous reports demonstrating protective effects for creatine in models of neurodegeneration, Bender et al. tested the hypothesis whether creatine might also facilitate healthy aging, particularly of the brain, in wild-type mice. In essence, feeding mice a diet containing 1% creatine from 12-month of age onwards, significantly increased both mean and maximum life span in comparison to control mice. Somewhat confirming what was said already above, the creatine-fed mice did not differ in the rotarod and grip strength analyses; however, creatine feeding improved (p<0.05) several markers of memory performance such as object recognition. Also, biomarkers of brain aging due to oxidative stress tended to be lower in the creatine-fed group. Based on gene expression profiling experiments, the authors conclude that creatine not only reversely regulates gene expression altered in aging, but also concordantly affects gene expression as in mice on caloric restriction. Whether this effect of creatine is due to the induction of mild stress like in the case of caloric restriction is unknown. Another potential mechanism of creatine-induced neuroprotection might be the prevention of ROS (recative oxygen species) generation due to enhanced activity of mitochondrial creatine kinase activity, as recently shown by Meyer et al. (JBC 281).
In light of the rather minor safety concerns raised regarding creatine supplementation, it might be worth to further explore the potential of this amino acid derivative to improve healthy aging.