Preparation of gallic acid-loaded chitosan nanoparticles and their chemoprotective effects on N-ethyl-N-nitrosourea-induced hepatotoxicity and mortality in rats

Abstract

N-ethyl-N-nitrosourea (ENU) as n-nitrosamine and alkylating agent, ubiquitous within living cells and in the environment can act as a full carcinogen and induce tumor formation in various tissues such as liver. In this study, gallic acid-loaded chitosan nanoparticles (GANPs) were synthesized and evaluated for their chemopreventive effect against ENU-induced hepatotoxicity and mortality in rats. Twenty-four male Wistar rats were divided into four groups including: control, ENU (single doses of 50 mg/kg via intraperitoneal injection), GA + ENU and GANPs + ENU. Animals were orally pretreated with GA (50 mg/kg) and GANPs (50 mg/kg) for 30 days, and liver injuries induced by ENU on the 31st day of study. After ENU administration, weight changes and mortality were monitored during 30 days, and then the animals were sacrificed and alpha-fetoprotein (AFP) as a tumor marker, liver function tests (ALT, AST and ALP), oxidative stress markers (GSH and MDA), mitochondrial toxicity parameters, and histopathological assessment were evaluated. Except for AFP and MDA, ENU caused significant elevation of liver enzymes, mitochondrial ROS formation, collapse of mitochondrial membrane potential depletion of GSH, histopathological abnormalities and mortality in rats. Our data showed that GANPs significantly increased the survival of rats by up to 66%, delayed in death time and prevented weight changes after exposure to ENU. Moreover, GANPs restored liver enzyme levels, ROS formation, mitochondrial dysfunction, GSH levels, and histopathological abnormalities towards normal. Our findings suggest that GANPs revealed a significant protective effect against deadly toxicity induced by ENU as an alkylating full carcinogen agent in liver tissue.

Keywords: Alkylating agents; Antioxidants; Chemical carcinogens; Liver cancer; N-nitrosamines.