Surya, Ramachandran and Vinitha, Anandan and Pillai, M. R and C C, Kartha (2018) Metformin attenuates effects of cyclophilin A on macrophages, reduces lipid uptake and secretion of cytokines by repressing decreased AMPK activity. Clinical science (London, England : 1979), 132 (6). pp. 719-738. ISSN 1470-8736

Text Metformin attenuates effects(Clinical Science 2018).pdf Restricted to Registered users only Download (2332Kb) | Request a copy

Abstract

Growing evidence implicates cyclophilin A secreted by vascular wall cells and monocytes as a key mediator in atherosclerosis. Cyclophilin A in addition to its proliferative effects, during hyperglycemic conditions, increases lipid uptake in macrophages by increasing scavenger receptors on the cell's surface. It also promotes macrophage migration across endothelial cells and conversion of macrophages into foam cells. Given the known effects of metformin in reducing vascular complications of diabetes, we investigated the effect of metformin on cyclophilin A action in macrophages. Using an ex vivo model of cultured macrophages isolated from patients with type 2 diabetes with and without coronary artery disease (CAD), we measured the effect of metformin on cyclophilin A expression, lipid accumulation, expression of scavenger receptors, plasma cytokine levels and AMP-activated protein kinase (AMPK) activity in macrophages. In addition, the effects of metformin on migration of monocytes, reactive oxygen species (ROS) formation, lipid uptake in the presence of cyclophilin A inhibitors and comparison with pioglitazone were studied using THP-1 monocytes. Metformin reduced cyclophilin A expression in human monocyte-derived macrophages. Metformin also decreased the effects of cyclophilin A on macrophages such as oxidized low-density lipoprotein (oxLDL) uptake, scavenger receptor expression, ROS formation and secretion of inflammatory cytokines in high-glucose conditions. Metformin reversed cyclophilin A-induced decrease in AMPK-1α activity in macrophages. These effects of metformin were similar to those of cyclophilin A inhibitors. Metformin can thus function as a suppressor of pro-inflammatory effects of cyclophilin A in high-glucose conditions by attenuating its expression and repressing cyclophilin A-induced decrease in AMPK-1α activity in macrophages.

Item Type:	Article
Uncontrolled Keywords:	AMPK; Cyclophilin A; Macrovascular complications; atherosclerosis; metformin; oxidative stress
Subjects:	Cardiovascular Diseases And Diabetes Biology
Depositing User:	Central Library RGCB
Date Deposited:	27 Jul 2018 07:28
Last Modified:	27 Jul 2018 07:28
URI:	http://rgcb.sciencecentral.in/id/eprint/667

Actions (login required)

View Item