Oxidized LDL Increase the Proinflammatory Profile of Human Visceral Adipocytes Produced by Hypoxia

Background: Little is known about the effects of hypoxia on scavenger receptors (SRs) levels in adipocytes. We analyzed the effect of morbid obesity and hypoxia on SRs and inflammation markers in human visceral adipocytes and whether ox-LDL modify the inflammatory profile produced by hypoxia. Methods: We studied in 17 non-obese and 20 subjects with morbid obesity (MO) the mRNA expression of HIF-1 alpha, SRs (LOX-1, MSR1, CL-P1 and CXCL16), IL6 and TNF alpha in visceral adipocytes and the effect of hypoxia with or without ox-LDL on visceral in vitro-differentiated adipocytes (VDA). Results: HIF-1 alpha, TNF alpha, IL6, LOX-1, MSR1 and CXCL16 expression in adipocytes was increased in MO when compared with those in non-obese subjects (p < 0.05). The expression of most of the inflammatory markers and SRs gene correlated with HIF-1 alpha. In VDA, hypoxia increased TNF alpha, IL6, MSR1, CXCL16 and CL-P1 (p < 0.05) in non-obese subjects, and TNF alpha, IL6, MSR1 and CXCL16 (p < 0.05) in MO. Silencing HIF-1 alpha prevented the increase of TNF alpha, IL6, LOX-1, MSR1, CL-P1 and CXCL16 expression (p < 0.05). The combination of hypoxia and ox-LDL produced higher TNF alpha expression (p = 0.041). Conclusions: Morbid obesity and hypoxia increased SRs and inflammatory markers in visceral adipocytes. In a hypoxic state, ox-LDL increased the proinflammatory response of visceral adipocytes to hypoxia.

Automated summary

Morbid obesity and hypoxia lead to increased levels of scavenger receptors (SRs) and inflammatory markers in visceral adipocytes. In a hypoxic state, ox-LDL enhances the proinflammatory response of visceral adipocytes to hypoxia.