Search results for "mitochondrial"

The adverse redox biochemistry of intramembrane thiols accounts for the lifespan-dependent cysteine depletion in the inner mitochondrial membrane of …

2013

Mitochondrial oxidative stress plays a key role in aging and apoptosis

2000

Harman first suggested in 1972 that mitochondria might be the biological clock in aging, noting that the rate of oxygen consumption should determine the rate of accumulation of mitochondrial damage produced by free radical reactions. Later in 1980 Miquel and coworkers proposed the mitochondrial theory of cell aging. Mitochondria from postmitotic cells use O2 at a high rate, hence releasing oxygen radicals that exceed the cellular antioxidant defences. The key role of mitochondria in cell aging has been outlined by the degeneration induced in cells microinjected with mitochondria isolated from fibroblasts of old rats, especially by the inverse relationship reported between the rate of mitoch…

Mitochondria, oxidative stress and aging

2000

In the eighties, Miquel and Fleming suggested that mitochondria play a key role in cellular aging. Mitochondria, and specially mitochondrial DNA (mtDNA), are major targets of free radical attack. At present, it is well established that mitochondrial deficits accumulate upon aging due to oxidative damage. Thus, oxidative lesions to mtDNA accumulate with age in human and rodent tissues. Furthermore, levels of oxidative damage to mtDNA are several times higher than those of nuclear DNA. Mitochondrial size increases whereas mitochondrial membrane potential decreases with age in brain and liver. Recently, we have shown that treatment with certain antioxidants, such as sulphur-containing antioxid…

Mitochondrial Markers in Aging and Primary Open-Angle Glaucoma

2020

This review focuses on recent progress in understanding the role of mitochondrial markers in the context of mitochondrial dysfunction in glaucoma and discussing new therapeutic approaches to modulate mitochondrial function and potentially lead to improved outcomes in glaucoma.

Humanin: A mitochondria-derived peptide with emerging properties.

2020

Age affects the metabolic rate of insect brain.

1984

Abstract Brains of adult insects can be isolated and studied vitro. In female blowflies the oxygen uptake of the brain is age dependent. A steady increase is followed by a precipitous decrease around the middle of the life span. These changes are accompanied by alterations of mitochondrial structure and deposits of lipofuscin-like material.

PGC-1α, Inflammation, and Oxidative Stress: An Integrative View in Metabolism

2020

Peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α is a transcriptional coactivator described as a master regulator of mitochondrial biogenesis and function, including oxidative phosphorylation and reactive oxygen species detoxification. PGC-1α is highly expressed in tissues with high energy demands, and it is clearly associated with the pathogenesis of metabolic syndrome and its principal complications including obesity, type 2 diabetes mellitus, cardiovascular disease, and hepatic steatosis. We herein review the molecular pathways regulated by PGC-1α, which connect oxidative stress and mitochondrial metabolism with inflammatory response and metabolic syndrome. PGC-1α regula…

Telmisartan as metabolic modulator: a new perspective in sports doping?

2011

The World Antidoping Agency (WADA) has introduced some changes in the 2012 prohibited list. Among the leading innovations to the rules are that both 5-aminoimidazole-4-carboxamide-1-[beta]-D-ribofuranoside (peroxisome proliferator�activated receptor-[delta] [PPAR-[delta]]-5' adenosine monophosphate-activated protein kinase [AMPK] agonist) and GW1516 (PPAR-[delta]-agonist) are no longer categorized as gene doping substances in the new 2012 prohibited list but as metabolic modulators in the class �Hormone and metabolic modulators.� This may also be valid for the angotensin II receptor blocker telmisartan. It has recently been shown that telmisartan might induce similar biochemical, biological…

Glutathione-dependent formaldehyde dehydrogenase (ADH3) and low km mitochondrial aldehyde dehydrogenase (ALDH2). New evidence for differential expres…

2011

Epidemiological and experimental studies support the involvement of lipid peroxidation (LPO) in retinal diseases. In addition to other pathogenic mechanisms not fully understood, the possibility remains that peroxidic aldehydes, acting as cytotoxic chemicals, mediate in the progression of chronic ocular disorders.To test proper mechanisms involved in removing peroxidic aldehydes from the retina, in an attempt to understand long-lasting changes induced by LPO, the oxidative and antioxidant enzymatic activities, as well as the retinal distribution and activity of glutathione-dependent formaldehyde dehydrogenase (ADH3) and low km mitochondrial aldehyde dehydrogenase (ALDH2), were studied and c…

Mitochondrial aldehyde dehydrogenase (ALDH-2)--maker of and marker for nitrate tolerance in response to nitroglycerin treatment.

2008

The hemodynamic and anti-ischemic effects of nitroglycerin (GTN) are rapidly blunted as a result of the development of nitrate tolerance. Long-term nitrate treatment also is associated with decreased vascular responsiveness caused by changes in intrinsic mechanisms of the tolerant vasculature itself. According to the oxidative stress concept, increased vascular superoxide and peroxynitrite production as well as an increased sensitivity to vasoconstrictors secondary to activation of protein kinase C as well as vascular NADPH oxidases contribute to the development of tolerance. Recent experimental work has defined new tolerance mechanisms, including inhibition of the enzyme that bioactivates …