Peperomia pellucida Extract Mitigates Cigarette Smoke-Induced Hepatic Histopathological Injury in Wistar Rats: A Post-Exposure Treatment Study

Tobacco smoke is a systemic toxicant whose health effects extend beyond the cardiopulmonary system to metabolically active organs such as the liver. Because interventions are often initiated only after exposure has occurred, post-exposure strategies that facilitate hepatic recovery warrant investigation. Peperomia pellucida is a phytochemical-rich medicinal herb with reported antioxidant and anti-inflammatory activity; however, its therapeutic potential against smoke-associated hepatic injury in a post-exposure setting remains incompletely defined. In this controlled, parallel-group study, an ethanolic extract of authenticated P. pellucida was evaluated in male Wistar rats. Thirty rats (6-8 weeks; 220-280 g) were randomized to SHAM, SMOKE, or SMOKE+EXTRACT (n=10/group). The SMOKE and SMOKE+EXTRACT groups underwent cigarette smoke exposure for 4 weeks (1 cigarette/rat/day), followed by a 4-week treatment phase in which SMOKE+EXTRACT received P. pellucida (200 mg/kg body weight, orally once daily) and the remaining groups received vehicle. At week 8, livers were processed for H&E staining and assessed on anonymized slides by a blinded pathologist (Olympus BX43) using an ordinal 0-3 grading system for steatosis, inflammation, necrosis, and fibrosis. Smoke exposure induced marked architectural disruption with inflammatory infiltration and congestion and increased injury scores across all domains versus SHAM (p < 0.0001). Post-exposure P. pellucida significantly reduced injury severity, with the largest effects on steatosis and necrosis (p < 0.01) and smaller but significant improvements in inflammation and fibrosis (p < 0.05). These data provide preclinical evidence that P. pellucida may promote histological recovery following cigarette smoke exposure.