Department of Pharmacology, Chongqing Medical University, Chongqing 400016, PR China.
Mol Cell Endocrinol. 2009 Nov 13;311(1-2):11-7. doi: 10.1016/j.mce.2009.03.023. Epub 2009 Apr 8.
To investigate the influence of melanin-concentrating hormone receptor 2 (MCHR2) on preadipocyte proliferation and differentiation, a 3T3-L1-MCHR2 cell line stably expressing human MCHR2 was established. The expression level and biological activity of MCHR2 were evaluated by immunofluorescence and radioligand binding assays. A 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) assay and cell cycle analysis showed that MCH did not affect 3T3-L1-MCHR2 and 3T3-L1-mock cell proliferation. MCH accelerated preadipocyte differentiation of the two cell lines when they were administered various doses of standard adipogenic inducers. The rate and degree of differentiation of the 3T3-L1-MCHR2 cells were higher than those of the 3T3-L1-mock cells. The expression levels of adipocyte-specific marker genes, including peroxisome proliferator-activated receptorgamma2 (PPARgamma2), CCAAT enhancer-binding proteinalpha (C/EBPalpha), adipocyte-specific fatty acid-binding protein (aP(2)) and leptin were significantly up-regulated, especially in 3T3-L1-MCHR2 cells. These findings suggest that MCHR2 positively mediates the regulation of MCH during preadipocyte differentiation and is involved in energy balance regulation without affecting preadipocyte proliferation.
为了研究黑素浓缩激素受体 2（MCHR2）对前脂肪细胞增殖和分化的影响，我们建立了稳定表达人 MCHR2 的 3T3-L1-MCHR2 细胞系。通过免疫荧光和放射性配体结合测定评估 MCHR2 的表达水平和生物学活性。3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐（MTT）测定和细胞周期分析表明，MCH 不影响 3T3-L1-MCHR2 和 3T3-L1-对照细胞的增殖。当给予两种细胞系不同剂量的标准脂肪生成诱导剂时，MCH 加速了前脂肪细胞的分化。3T3-L1-MCHR2 细胞的分化率和程度高于 3T3-L1-对照细胞。脂肪细胞特异性标记基因的表达水平，包括过氧化物酶体增殖物激活受体γ2（PPARγ2）、CCAAT 增强子结合蛋白α（C/EBPα）、脂肪细胞特异性脂肪酸结合蛋白（aP（2））和瘦素，显著上调，特别是在 3T3-L1-MCHR2 细胞中。这些发现表明，MCHR2 正向调节 MCH 在人前脂肪细胞分化过程中的作用，参与能量平衡调节，而不影响前脂肪细胞增殖。
