title: A comparison of melatonin and α-lipoic acid in the induction of antioxidant defences in L6 rat skeletal muscle cells.
abstract: Aging is characterized by a progressive deterioration in physiological functions and metabolic processes. The loss of cells during aging in vital tissues and organs is related to several factors including oxidative stress and inflammation. Skeletal muscle degeneration is common in elderly people; in fact, this tissue is particularly vulnerable to oxidative stress since it requires large amounts of oxygen, and thus, oxidative damage is abundant and accumulates with increasing age. Melatonin (N-acetyl-5-methoxytryptamine) is a highly efficient scavenger of reactive oxygen species and it also exhibits beneficial anti-inflammatory and anti-aging effects. This study investigated the susceptibility of rat L6 skeletal muscle cells to an induced oxidative stress following their exposure to hydrogen peroxide (50 μM) and evaluating the potential protective effects of pre-treatment with melatonin (10 nM) compared to the known beneficial effect of alpha-lipoic acid (300 μM). Hydrogen peroxide-induced obvious oxidative stress; it increased the expression of tumour necrosis factor-alpha and in turn promoted nuclear factor kappa-B and overrode the endogenous defence mechanisms. Conversely, pre-treatment of the hydrogen peroxide-exposed cells to melatonin or alpha-lipoic acid increased endogenous antioxidant enzymes, including superoxide dismutase-2 and heme oxygenase-1; moreover, they ameliorated significantly oxidative stress damage and partially reduced alterations in the muscle cells, which are typical of aging. In conclusion, melatonin was equally effective as alpha-lipoic acid; it exhibited marked antioxidant and anti-aging effects at the level of skeletal muscle in vitro even when it was given in a much lower dose than alpha-lipoic acid.
authors.affiliation: Division of Anatomy and Physiopathology, Department of Clinical and Experimental Sciences, University of Brescia, Viale Europa 11, 25123, Brescia, Italy.
authors.forename: Gaia
authors.initials: G
authors.lastname: Favero
authors.forename: Luigi Fabrizio
authors.initials: LF
authors.lastname: Rodella
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Nardo
authors.forename: Lorena
authors.initials: L
authors.lastname: Giugno
authors.forename: Marco Angelo
authors.initials: MA
authors.lastname: Cocchi
authors.forename: Elisa
authors.initials: E
authors.lastname: Borsani
authors.forename: Russel J
authors.initials: RJ
authors.lastname: Reiter
authors.forename: Rita
authors.initials: R
authors.lastname: Rezzani
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D018929:Cell Culture Techniques; D002470:Cell Survival; D006861:Hydrogen Peroxide; D008550:Melatonin / Q000494:pharmacology*; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000473:pathology; D032446:Myoblasts / Q000187:drug effects*; D018384:Oxidative Stress / Q000187:drug effects*; D051381:Rats; D008063:Thioctic Acid / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D008063:Thioctic Acid; D006861:Hydrogen Peroxide; D008550:Melatonin