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.