Nacre extract from pearl oyster suppresses LPS-induced depression and anxiety

Abstract

Pearl powder (nacreous layer) has been used in traditional Chinese medicine, as well as in functional foods and cosmetics. The present study was undertaken to investigate the beneficial effects of the extract from the nacreous layer of pearl oyster shells (nacre extract) in lipopolysaccharide (LPS)-induced depression and anxiety in mice. Nacre extract treatment improved depression-and anxiety-like behaviors and prevented oxidative stress by increasing the expression of nuclear factor E2-related factor (Nrf2). We found that LPS treatment decreased the expression of the 5-hydroxytryptamine (HT)1A receptor and increased the expression of the 5-HT2A receptor compared to control mice, but nacre extract reversed the changes in LPS-induced expression. LPS treatment also decreased the expression of brain-derived neurotrophic factor (BDNF) compared to control mice, and treatment with nacre extract restored the expression level. These results suggest that nacre extract ameliorates LPS-induced depression- and anxiety-like behavior.

Keywords

• Anxiety
• BDNF
• Depression
• nacre extract
• Nrf2
• 5-HT1A receptor