Naringin improves lipopolysaccharide-induced depression-like behaviors in mice

Objective To investigate the effects of naringin (Nar) on lipopolysaccharide (LPS)-induced depression-like behaviors in mice. Methods Thirty C57BL/6 male mice (8 weeks old, SPF grade, weighting 20~23 g) were randomly divided into 3 groups (n=10): control group, saline (Sal)+LPS group, and Nar+LPS group. The mice of the last group were pretreated with Nar (80 mg/kg, i.p., once a day for 8 consecutive days). The exploratory behavior and anxiety-like behavior in mice were assessed by open field test, light and dark box experiment and elevated plus maze test. Sugar water preference test, hanging tail test and forced swimming test were used to evaluate the depression-like behaviors of the mice. Immunohistochemical assay for Iba1 was adopted to detect the effects of Nar and LPS treatments on the number of microglia in the hippocampus of mice. Western blotting and qRT-PCR were performed to determine the protein expression of NF-κB and the mRNA levels of IL-1β, TNF-α and NF-κB in mouse hippocampus, respectively. Resu