Cell therapy improves cardiac function. Few cells have been investigated more extensively or consistently shown to be more effective than c-kit sorted cells; however, c-kit expression is easily lost during passage. Here, our primary goal was to develop an improved method to isolate c-kit(pos) cells and maintain c-kit expression after passaging.
View Article and Find Full Text PDFIn both preclinical and clinical studies, cell transplantation of several cell types is used to promote repair of damaged organs and tissues. Nevertheless, despite the widespread use of such strategies, there remains little understanding of how the efficacy of cell therapy is regulated. We showed previously that augmentation of a unique, metabolically derived stress signal (i.
View Article and Find Full Text PDFDerangements in metabolism and related signaling pathways characterize the failing heart. One such signal, O-linked β-N-acetylglucosamine (O-GlcNAc), is an essential post-translational modification regulated by two enzymes, O-GlcNAc transferase and O-GlcNAcase (OGA), which modulate the function of many nuclear and cytoplasmic proteins. We recently reported reduced OGA expression in the failing heart, which is consistent with the pro-adaptive role of increased O-GlcNAcylation during heart failure; however, molecular mechanisms regulating these enzymes during heart failure remain unknown.
View Article and Find Full Text PDFCardiovascular function is regulated at multiple levels. Some of the most important aspects of such regulation involve alterations in an ever-growing list of posttranslational modifications. One such modification orchestrates input from numerous metabolic cues to modify proteins and alter their localization and/or function.
View Article and Find Full Text PDFIndian J Biochem Biophys
February 2009
Chronic exposure to psychological stress in humans and restraint stress in experimental animals results in increased oxidative stress and resultant tissue damage. To study the contribution of stress hormones towards stress-induced oxidative processes in the brain, we investigated the response of important free-radical scavenging enzymes toward chronic administration of two doses of corticosterone (low dose: 10 mg/kg/day, high dose: 40 mg/kg/day) in rodents. After a 21-day experimental period, a significant decline in both superoxide dismutase and catalase was observed in both stressed and stress hormone-treated animals.
View Article and Find Full Text PDFProg Neuropsychopharmacol Biol Psychiatry
March 2009
Oxidative stress is a critical route of damage in various psychological stress-induced disorders, such as depression. Antidepressants are widely prescribed to treat these conditions; however, few animal studies have investigated the effect of these drugs on endogenous antioxidant status in the brain. The present study employed a 21-day chronic regimen of random exposure to restraint stress to induce oxidative stress in brain, and behavioural aberrations, in rodents.
View Article and Find Full Text PDFPhysical and psychological stressors not only enhance activity of the hypothalamo-pituitary-adrenocortical axis, but also cause oxidative damage by inducing an imbalance between the in vivo pro-oxidant and antioxidant status. The involvement of adrenal steroid stress hormones in oxidative damage associated with these stressors has not been extensively investigated. Therefore, this study was designed to probe any direct role of glucocorticoids on induction of oxidative processes by comparing the effects of low, intermediate and high doses of exogenously administered corticosterone, without other applied stressors, on a wide range of key components of the antioxidant defence system.
View Article and Find Full Text PDFEur J Pharmacol
October 2007
Stress plays a potential role in the onset and exacerbation of depression. Chronic restraint stress in rats, and psychosocial stress in humans, is implicated in the pathophysiology of mood and anxiety disorders. Oxidative damage is an established outcome of restraint stress, which has been suggested to induce many damaging processes contributing to the pathology of stress-induced depression.
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