Antioxidant and Anti-Inflammatory Activities of Probiotic Strains

This review highlights the anti-inflammatory and antioxidant effects of probiotics and their complex health-related impacts. The main health areas targeted are gastrointestinal inflammation, neuroinflammation, systemic metabolic disorders, and liver conditions. Probiotics work mechanistically to regulate key inflammatory pathways by suppressing nuclear factor (NF-κb) and mitogen-activated protein kinase (MAPK) pathways and activating antioxidant defenses through nuclear erythroid 2-related factor (Nrf2). They stimulate anti-inflammatory cytokines (including interleukin 10 (IL-10) and inhibit pro-inflammatory mediators such as tumor necrosis factor-α (TNF-α), partly through the regulation of T cells. Probiotics also produce antioxidant metabolites (e.g., exopolysaccharides and short-chain fatty acids), which enhance the host's resistance to oxidative stress. Supplementation with probiotics improves intestinal inflammation and oxidative injury in gut disorders. Clinical trials suggest that probiotic supplements may reduce neuroinflammation and oxidative stress, while improving cognitive or behavioral outcomes in neurodegenerative disorders. Overall, this review underscores that probiotics have potent anti-inflammatory and antioxidant effects within the gut-brain axis and across various organ systems, supporting their use as valuable adjunctive therapies for inflammatory and oxidative stress-related conditions. It further emphasizes that additional mechanistic research and controlled clinical trials are essential to translate these findings into the most effective therapeutic strategies.