OBJECTIVETo observe the changes of NYGGF4 gene expression during human preadipocyte differentiation and to explore the regulative role of tumor necrosis factor alpha (TNFalpha) on NYGGF4 gene expression in matured human adipocytes.

METHODSHuman preadipocytes-visceral (HPA-v) were cultured in vitro and differentiated into the matured adipocytes. Fully differentiated adipocytes were treated with TNFalpha in different concentrations for 16 hours or at 10 ng/mL for various times. Levels of the NYGGF4 mRNA were evaluated by real-time reverse transcription-PCR(RT-PCR).

RESULTS(1) After induction of differentiation, more than 90% of the HPAs-v exhibited typical adipocyte morphology on the 17th day. (2) In human preadipocytes, the level of NYGGF4 mRNA expression remained low. The NYGGF4 mRNA level was gradually increased with the preadipocytes being differentiated into the matured adipocytes, and reached the highest level in the fully differentiated adipocytes. (3) Treatment of the human matured adipocytes with TNFalpha resulted in a significant increase in the level of NYGGF4 mRNA. The up-regulatory effect of TNFalpha on the NYGGF4 gene expression tended to be enhanced with the increasing concentrations and elongation of time.

CONCLUSIONDuring human preadipocytes differentiation, the level of NYGGF4 gene mRNA expression increases gradually. TNFalpha could upregulate the expression of NYGGF4 mRNA in human matured adipocytes. The regulatory effect of TNFalpha on the NYGGF4 gene expression is of dose-dependent and time-correlated.