D-Ribose-L-cysteine confers pulmonary protection against formalin-induced oxidative and inflammatory perturbations in male Wistar rats

Formalin exposure (FE) is a significant environmental and occupational hazard that induces pulmonary toxicity via oxidative and nitrosative stress, inflammation and apoptosis, leading to structural and functional lung damage. This study evaluated the preventive and therapeutic effects of D-ribose-L-cysteine (DRLC), a glutathione-enhancing antioxidant, in male Wistar rats. Animals were assigned to control, formalin-exposed (5 ml of 40% formalin inhalation, 6 h/day), DRLC-only (250 mg/kg), preventive and reversal groups. Lung tissues were assessed for oxidative stress markers, inflammatory mediators, apoptotic indices and histopathological alterations using spectrophotometry, ELISA and hematoxylin and eosin staining, respectively. Formalin exposure reduced weight gain, increased lung weight index, elevated malondialdehyde and nitrite levels, depleted antioxidant defenses, activated NF-κB – mediated inflammation and induced mitochondrial-mediated apoptosis, with severe histological damage. DRLC administration significantly mitigated these effects, restoring antioxidant capacity, suppressing inflammatory and apoptotic signaling and preserving lung architecture, with greater efficacy observed in the preventive regimen.