Antioxidant and anti-aging role of silk sericin in D-galactose induced mice model

The main purpose was to elucidate the potential anti-aging impact of sericin, due to its anti-oxidant potential in D-galactose induced mice model. To induce natural aging in mice, a solution of 0.9 % saline containing D-galactose (250 mg/kg b.w.) was injected intraperitoneally for a period of 60 days. In this experiment, 56 male mice were arbitrarily categorized into 8 groups (1: control; 2: D-Galactose (250 mg/kg b.w), Group 3: Sericin (150 mg/kg b.w), Group 4: Metformin (150 mg/kg), Group 5: sericin (P), Group 6; sericin (T), Group 7; Met (P), Group 8; Met (T). The level of Glutathione reductase (2.1 ± 0.2 µmol/L), CAT (0.5 ± 0.0 mmol/mL), Superoxide dismutase (65.4 ± 1.7 U/mL), GSHPx (69.2 ± 1.7 U/l), T3 (3.1 ± 0.7 ng/mL), IL-2 (68.8 ± 1.5 Pg/mL), IL-4 (71.4 ± 4.2 Pg/mL), IgG (0.6 ± 0.0 mg/mL) and IgM (0.6 ± 0.0 mg/mL) were significantly (P < 0.05) decreased whereas the cortisol (22.0 ± 1.5 µg/L), and total cholesterol (229.4 ± 4.2 mg/dL)) were significantly elevated in D-galactose-treated /aged mice. However, administration of sericin significantly reduced the level of oxidative stress in aged mice. Real-time qPCR data showed that the level of telomere length- gene TERT significantly downregulated (10.43 ± 0.1) in the D-Gal-treated mice with respect to control (21.97 ± 0.5). The highest significant upregulation was found in the TERT gene when D-Gal-induced aged mice were treated with sericin (24.74 ± 0.3). Our outcomes showed that sericin gradually recovered the organ indices, and improved the histological changes of the brain, kidney, and liver in D-Gal-induced aging mice. Therefore, concluded that sericin possesses anti-aging effect against D-Gal-induced aging by diminishing oxidative stress, restoring the immune system, and enhancing the antioxidant defense system.