Therapeutic effect of probiotics on metabolic indices and clinical signs in age-related macular degeneration

Probiotics positively influence age-related macular degeneration (ARMD) given their propensity to attenuate oxidative and inflammatory stress. We addressed the impact of probiotics on metabolic profiles, clinical indices, inflammatory and oxidative stress parameters in ARMD patients. We performed a randomized, double-blind, placebo-controlled trial analyzing 57 subjects with ARMD aged between 50 and 85 years. Subjects were randomized into two groups, and received daily for 8 weeks either probiotic capsule or placebo. Fasting blood samples were obtained at baseline and after the 8-week intervention for the determination of metabolic profiles and oxidative stress biomarkers. After the 8-week intervention, compared with the placebo, probiotic supplementation significantly increased means HDL-cholesterol (Probiotic group: +3.86±4.42 vs. Placebo group: −0.55±4.93 mg/dL, P = .001), plasma total antioxidant capacity (TAC) (Probiotic group: +77.43±168.30 vs. Placebo group: −23.12±169.22 mmol/L, P = .02) and significantly decreased malondialdehyde (MDA) levels (Probiotic group: −0.18±0.46 vs. Placebo group: +0.18±0.25 µmol/L, P = .001). There was no significant effect of probiotic administration on other metabolic profiles and clinical symptoms. Overall, an eight-week probiotic administration among ARMD patients had beneficial effects on TAC, MDA and HDL-cholesterol levels; however, it did not affect clinical signs and other metabolic profiles.