title: Protective effects of dietary avocado oil on impaired electron transport chain function and exacerbated oxidative stress in liver mitochondria from diabetic rats.
abstract: Electron transport chain (ETC) dysfunction, excessive ROS generation and lipid peroxidation are hallmarks of mitochondrial injury in the diabetic liver, with these alterations also playing a role in the development of non-alcoholic fatty liver disease (NAFLD). Enhanced mitochondrial sensitivity to lipid peroxidation during diabetes has been also associated to augmented content of C22:6 in membrane phospholipids. Thus, we aimed to test whether avocado oil, a rich source of C18:1 and antioxidants, attenuates the deleterious effects of diabetes on oxidative status of liver mitochondria by decreasing unsaturation of acyl chains of membrane lipids and/or by improving ETC functionality and decreasing ROS generation. Streptozocin-induced diabetes elicited a noticeable increase in the content of C22:6, leading to augmented mitochondrial peroxidizability index and higher levels of lipid peroxidation. Mitochondrial respiration and complex I activity were impaired in diabetic rats with a concomitant increase in ROS generation using a complex I substrate. This was associated to a more oxidized state of glutathione, All these alterations were prevented by avocado oil except by the changes in mitochondrial fatty acid composition. Avocado oil did not prevented hyperglycemia and polyphagia although did normalized hyperlipidemia. Neither diabetes nor avocado oil induced steatosis. These results suggest that avocado oil improves mitochondrial ETC function by attenuating the deleterious effects of oxidative stress in the liver of diabetic rats independently of a hypoglycemic effect or by modifying the fatty acid composition of mitochondrial membranes. These findings might have also significant implications in the progression of NAFLD in experimental models of steatosis.
authors.affiliation: Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Edificio B-3. C.U., Avenida Fco. J. Mújica S/N, Morelia, Mich, 58030, Mexico.
authors.forename: Omar
authors.initials: O
authors.lastname: Ortiz-Avila
authors.forename: Marco Alonso
authors.initials: MA
authors.lastname: Gallegos-Corona
authors.forename: Luis Alberto
authors.initials: LA
authors.lastname: Sánchez-Briones
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Calderón-Cortés
authors.forename: Rocío
authors.initials: R
authors.lastname: Montoya-Pérez
authors.forename: Alain R
authors.initials: AR
authors.lastname: Rodriguez-Orozco
authors.forename: Jesús
authors.initials: J
authors.lastname: Campos-García
authors.forename: Alfredo
authors.initials: A
authors.lastname: Saavedra-Molina
authors.forename: Ricardo
authors.initials: R
authors.lastname: Mejía-Zepeda
authors.forename: Christian
authors.initials: C
authors.lastname: Cortés-Rojo
mesh_terms: D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism* / Q000473:pathology; D045222:Electron Transport Chain Complex Proteins / Q000378:metabolism; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism* / Q000473:pathology; D065626:Non-alcoholic Fatty Liver Disease / Q000378:metabolism* / Q000473:pathology; D018384:Oxidative Stress / Q000187:drug effects*; D027421:Persea; D010938:Plant Oils / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D045222:Electron Transport Chain Complex Proteins; D010938:Plant Oils; D017382:Reactive Oxygen Species