Oxidative Stress, Inflammation, and Chronic Diseases: Therapeutic Potential of Natural Products

Oxidative stress and chronic inflammation play central roles in the development of cardiovascular diseases, diabetes, neurodegenerative disorders, and cancer. Excess reactive oxygen species (ROS) disrupt redox homeostasis, damage biomolecules, and trigger pro-inflammatory signaling, contributing to cellular dysfunction and disease progression. This review systematically examined current literature on plant-derived natural products, focusing on their mechanisms of action, molecular targets, and therapeutic potential against oxidative stress-mediated chronic diseases. Databases including PubMed, Scopus, and Web of Science were searched for studies on major phytochemical classes—flavonoids, polyphenols, alkaloids, and terpenoids—and their biological effects. The evidence indicates that natural products exert multi-targeted effects through antioxidant activity, ROS scavenging, anti-inflammatory modulation, enzyme regulation, and signaling pathway control. Key molecular targets identified include the Nrf2 antioxidant pathway, NF-κB inflammatory pathway, MAPK cascades, and COX/LOX enzymes. Experimental studies demonstrate that phytochemicals such as quercetin, curcumin, resveratrol, and ginsenosides reduce oxidative damage, inhibit pro-inflammatory mediators, modulate apoptosis, and improve metabolic and vascular function. However, clinical translation is limited by poor bioavailability, lack of standardization, dose variability, and insufficient human trials. Emerging strategies, including nanotechnology-based delivery systems, synergistic therapy, and structural optimization, show promise in enhancing efficacy and stability. Integrating natural products into drug development pipelines with rigorous preclinical and clinical validation can facilitate their use as adjunctive or alternative therapies. This review highlights the mechanistic basis, therapeutic potential, and current limitations of natural products, offering insights for future research aimed at combating chronic oxidative stress-related diseases.