Effects of Antihypertensive and Triglyceride Lowering Agents on Splenocyte Apoptosis in Rats with Fatty Liver

Abstract

Individuals with the metabolic syndrome (MS) and non-alcoholic fatty liver disease (NAFLD) have an increased incidence of infection and infection-related mortality. Rats given fructose-enriched diet (FED) develop the MS including NAFLD. In this study, we characterized changes in splenocyte apoptosis in FED rats given medications to treat various components of the MS. Apoptosis of splenocytes may induce immunosuppression. Splenocyte apoptosis was evaluated by activated caspase-3 immunohistochemistry in the periarterial sheath (PALS), (a T cell area), follicles (B cell area), marginal (B cell area) and in the red pulp zones. FED administration caused an enormous increase in splenocyte apoptosis in all of the spleen zones: PALS (+2966%), follicles (+3025%), marginal (+5228%) and red pulp (+7000%). Administration of captopril to the FED rats was associated with a further increase in the splenocyte apoptosis only in the marginal (150%), PALS (+105%) and red pulp (+67%) zones. Bezafibrate administration to the FED rats was associated with no further increase in apoptosis rates. Amlodipine administration to the FED rats was associated with almost complete amelioration of the splenocyte apoptosis that was induced by the FED diet. These pharmacological manipulations were also associated with changes in the hepatic lipids composition, and oxidative milieu that did not correlate to the changes in splenocyte apoptosis. NAFLD in FED rats is associated with an increase in splenic apoptosis. Agents administered to treat components of the MS in FED rats may lead to divergent changes in the splenic histology and splenocyte apoptosis.