The Supplementation of Sechium edule var. nigrum spinosum (Chayote) Promotes Nrf2-Mediated Antioxidant Protection in Older Adults with Metabolic Syndrome.

The aim was to determine the effect of Sechium edule var. nigrum spinosum (chayote) on gene expression related to antioxidant protection mechanisms and the inflammatory process in older adults with metabolic syndrome (MetS). A quasi-experimental study was carried out in a convenience sample of 46 older adults diagnosed with MetS: (i) placebo group (PG; n = 20); (ii) experimental group (EG; n = 26). The clinical, biochemical, anthropometric parameters and SOD, GPx, and CAT enzyme activity, alongside total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), cytokines (IL-6, IL-8 and TNF-α), and mRNA expression of SOD, GPx, CAT, IL-6, IL-8, TNF-α, Nrf2, NFkB p50, and NFkB p65, were measured at baseline and 6 months post-intervention. A statistically significant decrease was observed in TOS (baseline, 28.9 ± 3.6 vs. post, 23.7 ± 3.4, p < 0.01) and OSI (baseline, 24.1 ± 3.8 vs. post, 17.7 ± 4), as well as an increase in IL-6 (baseline, 10.7 ± 1.1 vs. post, 12.3 ± 2, p = 0.03), SOD activity (baseline, 167.1 ± 11.9 vs. post, 180.6 ± 7.6, p < 0.05), CAT activity (baseline, 1.0 ± 0.2 vs. post, 1.3 ± 0.2, p < 0.01), and TAS (baseline, 1.1 ± 0.1 vs. post, 1.4 ± 0.1, p < 0.01) in the EG compared to the PG. Regarding the expression of Nrf2, SOD, and IL-6, the EG showed a significant increase vs. basal levels (47%, 44%, and 43%, respectively). Our findings suggest that Sechium edule supplementation promotes the antioxidant response and decreases oxidative stress via Nrf2.

Moderate exercise combined with metformin-treatment improves mitochondrial bioenergetics of the quadriceps muscle of old female Wistar rats.

Sarcopenia is a syndrome that leads to physical disability and that deteriorates elderly people´s life quality. The etiology of sarcopenia is multifactorial, but mitochondrial dysfunction plays a paramount role in this pathology. Our research group has shown that the combined treatment of metformin (MTF) and exercise has beneficial effects for preventing muscle loss and fat accumulation, by modulating the redox state. To get an insight into the mechanism of the combined treatment, the mitochondrial bioenergetics was studied in the mitochondria isolated from old female Wistar rats quadriceps muscles. The animals were divided into six groups; three performed exercise on a treadmill for 5 days/week for 20 months, and the other three were sedentary. Also, two groups of each were treated with MTF for 6 or 12 months. The rats were euthanized at 24 months. The mitochondria were isolated and supercomplexes formation along with oxygen consumption, ATP synthesis, and ROS generation were evaluated. Our results showed that the combined treatment for 12 months increased the complex I and IV activities associated with the supercomplexes, simultaneously, ATP synthesis increased while ROS production decreased, indicating a tightly coupled mitochondria. The role of exercise plus the MTF treatment against sarcopenia in old muscles is discussed.