Discovery of Anti-Aging Effects of Wheat Bran Extract in a D-Galactose-Induced Rat Model of Oxidative Stress.

Abstract

Background/Objectives: Wheat bran is known for its anti-aging effects, primarily due to its antioxidant properties. Our previous study identified novel antioxidants in wheat bran (xylo-oligosaccharides and protein hydrolysates) using an innovative extraction method. However, the anti-aging potential of these wheat bran extracts (WBEs) remains unclear. Methods: This study evaluated the anti-aging effects of WBE in a D-galactose-induced aging model using Wistar rats. Animals were divided into four groups: (1) saline-injected control, (2) D-galactose-injected control, (3) D-galactose + 5% WBE, and (4) D-galactose + 10% WBE. After six weeks, body weight, food intake, body fat percentage, erythrocyte superoxide dismutase (SOD) activity, and liver senescence-associated β-galactosidase (SA-β-gal) levels were assessed. Results: D-galactose significantly reduced food intake in positive control 87 ± 21%/weekly (negative control; p < 0.05, 107 ± 20%/weekly for 10%WBE; p < 0.01. Body fat percentage (positive control: 84 ± 19% vs. 5% WBE: 110 ± 20%, p < 0.05 in 100% convert). It also lowered erythrocyte SOD activity; 68.6 ± 9%, p < 0.01 in 100% conversion). WBE supplementation restored SOD activity in a dose-dependent manner (5% WBE: 32,479 ± 12,773 U/mL; 10% WBE: 42,368 ± 20,281 U/mL. Although D-galactose did not elevate significantly SA-β-gal activity in the liver, WBE supplementation still led to a dose-dependent reduction in baseline SA-β-gal levels (294 ± 84 nmol/min/mg protein vs. 5% WBE: 181 ± 65 nmol/min/mg protein, and 10% WBE: 146 ± 40 nmol/min/mg protein. p < 0.001). No significant group differences were found in hepatic SOD2, catalase (liver and skin), or telomerase reverse transcriptase expression. Conclusions: These findings suggest that wheat bran extracts mitigate D-galactose-induced oxidative stress in circulation, indicating potential anti-aging benefits. However, their effects at the tissue level remain inconclusive. Further studies are needed to explore molecular mechanisms and refine intervention duration.