[Regulative role of TNFalpha on STEAP4 gene in matured human adipocytes].

ABSTRACT

OBJECTIVE: Human STEAP4, a novel obesity-related gene, is associated with insulin sensitivity regulation in human adipocytes. This study aimed to explore the regulative role of TNFalpha on STEAP4 gene in matured human adipocytes. METHODS: Human preadipocytes were cultured and differentiated into matured adipocytes in vitro. Fully differentiated adipocytes (Day 17) were treated with different concentrations of TNFalpha (0, 5, 10, 25 and 50 ng/mL) for 24 hrs. Total RNA and protein were extracted from the adipocytes. Levels of STEAP4 mRNA and protein expression were determined by real-time quantitative RT-PCR and Western blot respectively. RESULTS: Different concentrations (5, 10, 25 and 50 ng/mL) of TNFalpha treatment for 24 hrs resulted in a significant increase in the STEAP4 mRNA expression of human matured adipocytes.The maximal effect was seen in the 50 ng/mL of TNFalpha treatment group. In parallel, STEAP4 protein synthesis in matured adipocytes increased in response to TNFalpha treatment of different concentrations (5, 10, 25 and 50 ng/mL) for 24 hrs. The maximal up-regulated effect was seen in the 25 ng/mL of TNFalpha treatment group. CONCLUSIONS: TNFalpha can up-regulate STEAP4 mRNA expression in human matured adipocytes.