Endocannabinoid receptor CB2 in nonalcoholic fatty liver disease

Background and Aim: Fatty infiltration and fibrosis are major issues in chronic liver disease. Recent reports suggest a role for the endocannabinoid system in these processes. Aim: To characterize localization and expression of CB2 in normal liver and nonalcoholic fatty liver. Methods: We studied 64 liver biopsies: eight were considered normal; 56 had a diagnosis of nonalcoholic fatty liver disease (NAFLD); 32 with nonalcoholic steatosis and 24 nonalcoholic steatohepatitis (NASH). CB2 immunolocalization was studied in 38 samples in paraffin blocks using immunohistochemistry, and a computerized semiquantitative analysis was carried out. CB2 mRNA expression was assessed through RT‐PCR in 26 frozen liver samples and the ratio CB2/β‐actin was used to evaluate differences between groups. Statistical analysis was performed with central tendency measures and the Mann–Whitney U‐test. We considered as significant differences those with a P‐value