Mangiferin regulates interleukin-6 and cystathionine-b-synthase in lipopolysaccharide-induced brain injury

Abstract

Mangiferin has been extensively applied in different fields due to its anti-inflammatory properties. However, the precise mechanism used by mangiferin on lipopolysaccharide (LPS)-induced inflammation has not been elucidated. Here, we discuss the potential mechanism of mangiferin during a LPS-induced brain injury. Brain injury was induced in ICR mice via intraperitoneal LPS injection (5 mg/kg). Open- and closed-field tests were used to detect the behaviors of mice, while immunoblotting was performed to measure the expression of interleukin-6 (IL-6) and cystathionine-b-synthase (CBS) in the hippocampus after mangiferin was orally administered (p.o.). Mangiferin relieved LPS-induced sickness 6 and 24 h after LPS injection; in addition, this compound suppressed LPS-induced IL-6 production after 24 h of LPS induction as well as the downregulation of LPS-induced CBS expression after 6 and 24 h of LPS treatment in the hippocampus. Therefore, mangiferin attenuated sickness behavior by regulating the expression of IL-6 and CBS.

Fig. 1

The chemical structure of mangiferin

Fig. 2

Effects of LPS (i.p.) and mangiferin (p.o.) after 6 h of LPS-treated mice on locomotor activity in the open-field test and close-field test. a The track maps of different groups. b Total distance traveled during 5 min. c Crossing lines during 5 min. (b, c) Values are mean ± SD (n = 12). *P < 0.05 versus respective saline group; ^# P < 0.05 versus respective LPS group. (CMC, carboxymethylcellulose sodium)

Fig. 3

Effects of LPS (i.p.) and mangiferin (p.o.) after 24 h of LPS injection mice on locomotor activity in the open-field test and close-field test. a The track maps of different groups. b Total distance traveled in 5 min. c Crossing lines in 5 min. (b, c) Values are mean ± SD (n = 12). *P < 0.05 versus respective saline group; ^# P < 0.05 versus respective LPS group. (CMC, carboxymethylcellulose sodium)

Fig. 4

Effects of mangiferin on the expression of IL-6 protein in mice hippocampus at 6 and 24 h after LPS treatment. a Immunoblotting analysis of the protein levels of IL-6 with anti-IL-6 antibodies. b The intensity of the bands was determined by optical density (O.D.) analysis. Data are the mean ± SD and were expressed as folds versus saline group. *P < 0.05 versus respective saline group; ^# P < 0.05 versus respective LPS group (n = 6). (CMC, carboxymethylcellulose sodium)

Fig. 5

Effects of mangiferin on the expression of CBS protein in mice hippocampus at 6 and 24 h after LPS treatment. a Immunoblotting analysis of the protein levels of CBS and actin with anti-CBS and anti-actin antibodies. b The intensity of the bands was determined by optical density (O.D.) analysis. Data are the mean ± SD and were expressed as folds versus saline group. *P < 0.05 versus respective saline group; ^# P < 0.05 versus respective LPS group (n = 6). (CMC, carboxymethylcellulose sodium)