Can electrons travel through actin microfilaments and generate oxidative stress in retinol treated Sertoli cell?
In early reports our research group has demonstrated that 7 microM retinol (vitamin A) treatment leads to many changes in Sertoli cell metabolism, such as up-regulation of antioxidant enzyme activities, increase in damage to biomolecules, abnormal cellular division, pre-neoplasic transformation, and cytoskeleton conformational changes. These effects were observed to be dependent on the production of reactive oxygen species (ROS), suggesting extra-nuclear (non-genomic) effects of retinol metabolism. Besides 7 microM retinol treatment causing oxidative stress, we have demonstrated that changes observed in cytoskeleton of Sertoli cells under these conditions were protective, and seem to be an adaptive phenomenon against a pro-oxidant environment resulting from retinol treatment. We have hypothesized that the cytoskeleton can conduct electrons through actin microfilaments, which would be a natural process necessary for cell homeostasis. In the present study we demonstrate results correlating retinol metabolism, actin architecture, mitochondria physiology and ROS, in order to demonstrate that the electron conduction through actin microfilaments might explain our results. We believe that electrons produced by retinol metabolism are dislocated through actin microfilaments to mitochondria, and are transferred to electron transport chain to produce water. When mitochondria capacity to receive electrons is overloaded, superoxide radical production is increased and the oxidative stress process starts. Our results suggested that actin cytoskeleton is essential to oxidative stress production induced by retinol treatment, and electrons conduction through actin microfilaments can be the key of this correlation.
de Oliveira
Ramatis Birnfeld
RB
Departamento de Bioquímica, Centro de Estudos em Estresse Oxidativo, Laboratório 32, ICBS-Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600 anexo, Porto Alegre, RS, Brazil. ramatusoliveira@yahoo.com.br
de Bittencourt Pasquali
Matheus Augusto
MA
Filho
Alfeu Zanotto
AZ
Dalmolin
Rodrigo Juliani Siqueira
RJ
Gelain
Daniel Pens
DP
Gottfried
Carmem
C
Rodrigues
José Luiz
JL
Klamt
Fábio
F
Moreira
José Cláudio Fonseca
JC
D000199:Actins / Q000378:metabolism* / Q000648:ultrastructure; D000818:Animals; D003571:Cytochalasin B / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism / Q000648:ultrastructure; D004583:Electrons; D008297:Male; D008564:Membrane Potentials / Q000502:physiology; D008928:Mitochondria / Q000378:metabolism; D018384:Oxidative Stress; D010766:Phosphorylation; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D012708:Sertoli Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D014801:Vitamin A / Q000494:pharmacology*; D014815:Vitamins / Q000494:pharmacology
D000199:Actins; D017382:Reactive Oxygen Species; D014815:Vitamins; D014801:Vitamin A; D003571:Cytochalasin B