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There is increasing evidence that aging is associated with oxidative damage, inflammation, and apoptosis in different cell types. However, there is limited information regarding aging mechanisms in colon smooth muscle. Old male Wistar rats (22 months) were treated for 10 wks with melatonin or growth hormone (GH). Animals were sacrificed at 24 months of age by decapitation. The colon was dissected and the smooth muscle homogenized. H(2)O(2) and malonyl dialdehyde (MDA) content and catalase and glutathione peroxidase (GPX) activities were determined using colorimetric kits. Expression of nuclear factor kappa B (NF-κB), cyclooxygenase 2 (COX-2), caspase-3, and caspase-9 were determined by Western blot. Aging of colon smooth muscle correlated with an increase in H(2)O(2) and MDA levels when compared with young animals in both proximal and distal segments; these changes were associated with a decrease in the catalase activity in the distal colon. Oxidative stress correlated with an increase in COX-2 and NF-κB expression, which were accompanied by an enhanced expression of the pro-apoptotic enzyme caspase-3 and its upstream enzyme, caspase-9. Melatonin treatment normalized the oxidative, inflammatory, and apoptotic patterns, whereas GH replacement, although effective in reducing oxidative stress in distal colon, did not reverse the age-related inflammation or apoptosis. These results suggest that melatonin should be the treatment of choice to most effectively recover physiological functions in aged colonic smooth muscle.

Aging is known to play a critical role in the etiopathogenesis of several diseases. Among them, cardiovascular disorders are especially relevant since they are becoming the first cause of death in western countries. Resveratrol is a polyphenolic compound that has been shown to exert beneficial effects at different levels, including neuronal and cardiovascular protection. Those effects of resveratrol are related, at least in part, to its antioxidant and anti-inflammatory properties. In the current investigation we were interested in exploring whether the positive effects of resveratrol at cardiac level were taking place even when the supplementation started in already old animals. MethodsOld male rats were supplemented with resveratrol during 10 weeks. Using RT-PCR, we analyzed the effects of resveratrol supplementation on the expression of different genes related to inflammation, oxidative stress and apoptosis in rat heart. ResultsResveratrol reverted the age-related changes in inflammatory, oxidative and apoptotic markers in the rat heart. Among others, the expression of two major inflammatory markers, INF-and TNF-and two oxidative markers, heme oxygenase and nitric oxide synthase, were increased with aging, and resveratrol supplementation reduced their levels to those observed in the heart of young animals. Moreover, age-related changes in apoptotic markers in rat heart were also reverted by resveratrol treatment. Conclusion 3Our results suggest that resveratrol might exert beneficial effects as an anti-aging compound in order to revert age-related changes in cardiac function.

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