Immunohistochemical, histopathological study and chemoprotective effect of Solanum nigrum in N-nitrosodiethylamine-induced hepatocellular carcinoma in Wistar rats

Background and Aim: Cancer is a devastating disease with a severe impact on the physical and psychological well-being of patients. Hepatocellular carcinoma (HCC) has been reported in various species of animals including dogs, cats, sheep, and pigs. The present study aimed to study the immunohistochemical and histopathological changes and chemoprotective effect of aqueous and alcoholic extracts of Solanum nigrum on N-nitrosodiethylamine (NDEA)-induced HCC rat model. Materials and Methods: Eighty-two male Wistar rats of 15 weeks of age weighing 200-250 g were selected for the experiment. They were randomly divided into ten groups. Group I served as normal control consisted of healthy rats. HCC was induced in Group II, IV, V, VI, VII, and X rats using NDEA as inducing agent followed by phenobarbitone as a promoter for 16 weeks. Group II rats were kept untreated as HCC control. Group III rats were kept as vehicle control (0.05% Sodium bicarbonate). Group IV and V rats were treated with aqueous extract of S. nigrum at 200 mg/kg and 400 mg/kg, respectively, and Group VI and VII rats were treated with an alcoholic extract of S. nigrum at 200 mg/kg and 400 mg/kg, respectively, daily orally for 28 days. Group X rats were treated with sorafenib as reference drug at a dose of 11.4 mg/kg daily orally for 28 days. Group VIII and IX rats were kept as aqueous and alcoholic extract control for studying the effect of the same on normal rats. Liver samples were collected to study the gross and histopathological lesions and the activity of cleaved caspase-3 and chemopreventive effect of aqueous and alcoholic extracts of S. nigrum on HCC. Results: The liver sections of rats from HCC control (Group II) showed loss of lobular architecture, necrosis, fatty change, enlarged and darkened nuclei with variable size, dilatation of hepatic sinusoids with Kupffer cell hyperplasia, dilatation and proliferation of bile duct, and intranuclear vacuoles and also showed the presence of more than one nucleolus. Administration of alcoholic extract of S. nigrum and sorafenib to NDEA/phenobarbital-treated rats reduced the severity of lesions in the liver. Immunohistochemical analysis of liver sections for caspase-3-positive cells of hepatic cancer-induced group showed immunoreactivity to rarely few. The immunoreactivity of the hepatocytes treated with a higher dose of alcoholic extract of S. nigrum was limited and was comparable to a standard drug, sorafenib. Conclusion: Oral administration of aqueous and alcoholic extracts of S. nigrum for 28 days showed significant rejuvenation in the structure of the liver in the histopathological section in a dose-dependent manner in rats.