Background: Secreted frizzled-related protein 5 (SFRP5) is an anti-inflammatory adipokine modulating metabolism dysfunction. This study aims to observe the effect of recombinant SFRP5 protein on nonalcoholic steatohepatitis (NASH). Methods: We set up a prokaryotic expression system and purified the recombinant SFRP5 protein. Recombinant SFRP5 protein was further identified by SDS-PAGE, western blot, high performance liquid chromatography (HPLC), protein mass spectrometry and in vitro Wnt5a-binding test. NASH mouse model was induced by methionine and choline deficient diet (MCDD) for 2 weeks. SFRP5 treatment group received intraperitoneal injection with a dosage of 10 mu g/kg SFRP5 twice a day for 2 weeks. Saline was used as control. Inflammation and fatty lesion score of liver tissue pathology and serum transaminase level were compared. Results: The purity of recombinant SFRP5 protein is 90% identified by HPLC. Its molecule size is 36,096.08 tested by mass spectrometry. Recombinant SFRP5 can specifically bind with Wnt5a which verifies its activity in vitro. The endotoxin level of this recombinant protein is 0.01EU/mu g-0.1EU/mu g and is suitable for animal experiment. SFRP5 can significantly improve liver inflammation (SFRP5 vs. control, 1.40 +/- 0.70 vs. 2.00 +/- 0.47, P < 0.05) as well as fatty lesion scores (SFRP5 vs. control, 1.40 +/- 0.97 vs. 2.20 +/- 0.63, P < 0.05), and lower ALT and AST levels. The mRNA expression of proinflammatory adipokines (IL-1 beta, IL-6, TNF alpha and MCP-1) in liver was down-regulated significantly after SFRP5 intervention. Immunohistochemistry and quantitative PCR revealed a dramatically down-regulation of F4/80 in liver after SFRP5 treatment. Conclusions: Recombinant SFRP5 protein significantly alleviated NASH induced by MCDD.
[1]Fudan Univ, Huashan Hosp, Dept Endocrinol, 12 Middle Wulumuqi Rd, Shanghai 200040, Peoples R China.
[2]Shanghai Anruite Biol Med Technol Co Ltd, 200 Newton Rd,Zhangjiang Hi Tech Pk, Shanghai 201210, Peoples R China.
(8.0+极速模式)