Cellular responses to H(2)O(2) and bleomycin-induced oxidative stress in L6C5 rat myoblasts.
In muscle cells, reactive oxygen species (ROS) are continually generated. It is believed that these molecules have a well-established role as physiological modulators of skeletal muscle functions, ranging from development to metabolism and from blood flow to contractile functions. Moreover, ROS may contribute to the development of muscle fatigue, inflammation, and degeneration, and may be implicated in many muscle diseases. The aim of the present study was to verify the role of short or prolonged exposure to oxidative stress, generated by different concentrations of H(2)O(2), on growth, chromosomal aberrations, and apoptosis induced in cultured L6C5 rat muscle cells used as model for myoblasts. Our results indicate that, in L6C5 cells, reactive oxygen intermediates (ROI) can activate distinct cell pathways leading to cell growth induction and development of resistant phenotype, or to chromosomal aberrations, cell cycle arrest, or cell death. The positive vs. negative effects of H(2)O(2)-altered redox potential in myoblasts are strictly related to the intensity of oxidative stress, likely depending on the types and number of cellular targets involved. Among these, DNA molecules appear to be very sensitive to breakage by H(2)O(2), although DNA damage is not directly responsible for ROI-induced apoptosis in L6C5 rat myoblasts.
Caporossi
Daniela
D
Department of Public Health and Cell Biology, University of Rome "Tor Vergata,", Rome, Italy. caporos@uniroma2.it
Ciafrè
Silvia Anna
SA
Pittaluga
Monica
M
Savini
Isabella
I
Farace
Maria Giulia
MG
D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis; D001205:Ascorbic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D001761:Bleomycin / Q000494:pharmacology*; D002374:Catalase / Q000378:metabolism; D002455:Cell Division; D002478:Cells, Cultured; D002869:Chromosome Aberrations; D004247:DNA / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005609:Free Radicals; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008938:Mitosis; D032342:Muscle Cells / Q000378:metabolism / Q000473:pathology*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010641:Phenotype; D051381:Rats; D017382:Reactive Oxygen Species; D013482:Superoxide Dismutase / Q000378:metabolism; D013997:Time Factors
D000964:Antimetabolites, Antineoplastic; D000975:Antioxidants; D005609:Free Radicals; D017382:Reactive Oxygen Species; D001761:Bleomycin; C011669:ascorbate-2-phosphate; D004247:DNA; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase; D001205:Ascorbic Acid