Protective role of dietary fiber against lead-induced cellular and renal toxicity in a diabetic mouse model: Implications for environmental health and safety

Lead (Pb) is a widespread environmental pollutant that poses a significant threat to human health through chronic exposure via contaminated air, water, and food. Individuals with metabolic disorders, such as diabetes, are particularly vulnerable to Pb-induced renal injury due to pre-existing oxidative stress and inflammation. This study investigated the protective effects of dietary fiber (DF) against Pb-induced cytotoxicity and nephrotoxicity using both in vitro (mouse podocytes and RAW 264.7 macrophages) and in vivo (db/db diabetic mice) models. DF significantly restored cell viability and reduced the expression of pro-inflammatory cytokines (TNF-α, IL-6) and COX-2 in Pb-exposed cells. In diabetic mice, Pb exposure aggravated renal damage, as evidenced by elevated nephrin and E-cadherin expression and structural alterations, while DF co-treatment attenuated these molecular markers, indicating a nephroprotective effect. Although histological recovery was limited, molecular analyses confirmed that DF mitigates Pb-induced inflammatory and epithelial stress responses. These findings highlight the potential of DF as a cost-effective nutritional strategy to reduce heavy metal burden and protect environmentally vulnerable populations, especially those with underlying metabolic diseases, from the adverse health effects of chronic Pb exposure.