RESUMEN
The natural polyphenol resveratrol (RSV) might counteract the skeletal muscle age-related loss of muscle mass and strength/function partly acting on mitochondria. This work analysed the effects of a six-week administration of RSV (50 mg/kg/day) in the oxidative Soleus (Sol) skeletal muscle of old rats (27 months old). RSV effects on key mitochondrial biogenesis proteins led to un unchanged amount of SIRT1 protein and a marked decrease (60 %) in PGC-1α protein. In addition, Peroxyredoxin 3 (PRXIII) protein decreased by 50 %, which on overall suggested the absence of induction of mitochondrial biogenesis by RSV in old Sol. A novel direct correlation between PGC-1α and PRXIII proteins was demonstrated by correlation analysis in RSV and ad-libitum (AL) rats, supporting the reciprocally coordinated expression of the proteins. RSV supplementation led to an unexpected 50 % increase in the frequency of the oxidized base OH8dG in mtDNA. Furthermore, RSV supplementation induced a 50 % increase in the DRP1 protein of mitochondrial dynamics. In both rat groups an inverse correlation between PGC-1α and the frequency of OH8dG as well as an inverse correlation between PRXIII and the frequency of OH8dG were also found, suggestive of a relationship between oxidative damage to mtDNA and mitochondrial biogenesis activity. Such results may indicate that the antioxidant activity of RSV in aged Sol impinged on the oxidative fiber-specific, ROS-mediated, retrograde communication, thereby affecting the expression of SIRT1, PGC-1α and PRXIII, reducing the compensatory responses to the age-related mitochondrial oxidative stress and decline.
Asunto(s)
Envejecimiento , Mitocondrias Musculares , Músculo Esquelético , Biogénesis de Organelos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Ratas Wistar , Resveratrol , Sirtuina 1 , Animales , Resveratrol/farmacología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Masculino , Envejecimiento/efectos de los fármacos , Envejecimiento/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Sirtuina 1/metabolismo , Mitocondrias Musculares/efectos de los fármacos , Mitocondrias Musculares/metabolismo , Ratas , Estilbenos/farmacología , Antioxidantes/farmacología , Peroxirredoxinas/metabolismo , ADN Mitocondrial/metabolismo , Estrés Oxidativo/efectos de los fármacos , Dinaminas/metabolismo , Dinámicas Mitocondriales/efectos de los fármacosRESUMEN
Supercritical fluid extraction (SFE) was used to extract bioactive compounds from apple (Malus domestica) peel waste from three different Italian cultivars. The bioactive fractions were extracted applying a temperature of 60 °C and a pressure of 250 bar for 15 min with 20% ethanol as co-solvent, at a flow rate of 2 mL/min. The total polyphenol (TP), anthocyanin (TA), ascorbic acid (AA), and antioxidant activity contents (TACs) were measured, while chromatographic analyses were performed to highlight the differences between the extracts. The Stark cultivar had the highest levels of polyphenols, anthocyanins, and ascorbic acid, while the Royal Gala cultivar showed the highest total antioxidant activity. SFE extracts were then tested for their effect on the mitochondrial NADH-ubiquinone oxidoreductase (Complex I) activity on mitochondria isolated from human embryonic kidney cells (HEK239). The Stark extract showed the most positive response in terms of NADH oxidation. The results obtained in this work highlight the potential of apple peel waste as a source of functional phytocompounds and suggest that Stark cultivar extracts may be exploited for pharmacological applications. This study supports the circular bioeconomy by promoting the use of waste products as a valuable resource.