Hepatic Effects of Cigarette Smoke Exposure: Enzymatic and Histological Evidence from Wistar Rats

Abstract

Cigarette smoke contains numerous toxic compounds capable of inducing systemic effects, including alterations in hepatic function. This study investigated the effects of chronic cigarette smoke exposure on liver enzyme activity and histological architecture in male Wistar rats. Twenty rats were randomly divided into two groups (n = 10 each): a control group and a smoke-exposed group. The exposed group was subjected to cigarette smoke inhalation daily for a period of four weeks, while the control group was maintained under normal laboratory conditions. At the end of the exposure period, blood samples were collected for biochemical analysis of liver enzymes, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP). Liver tissues were also harvested for histopathological examination using standard staining techniques. Statistical analysis was performed using one-way analysis of variance (ANOVA), with significance set at p < 0.05. Results showed a significant decrease (p < 0.05) in serum ALT, AST, and ALP levels in the smoke-exposed group compared to the control. Histological evaluation revealed largely preserved hepatic architecture, with only mild inflammatory changes observed in some samples. The observed reduction in liver enzyme activity may suggest an alteration in hepatic metabolic function or possible enzyme suppression following chronic smoke exposure. In conclusion, chronic exposure to cigarette smoke modulates liver enzyme activity in Wistar rats, with minimal observable histological damage under the conditions of this study. Further investigations incorporating oxidative stress and molecular biomarkers are recommended to elucidate the underlying mechanisms.