Ohsumi J, Miyadai K, Kawashima I, Sakakibara S, Yamaguchi J, Itoh Y
Biomedical Laboratories, Sankyo Co., Ltd., Tokyo, Japan.
Biochem Mol Biol Int. 1994 Mar;32(4):705-12.
Interleukin-11/adipogenesis inhibitory factor (IL-11/AGIF) inhibits adipogenesis and suppresses lipoprotein lipase (EC3.1.1.34, LPL) activity in adipocytes (1,2). We investigated the mechanism of suppression of LPL activity in 3T3-L1 adipocytes by IL-11/AGIF. Incubation of adipocytes with 50 ng/ml of IL-11/AGIF led to a 75% decrease in LPL activity within 8 hours, whereas LPL mRNA level decreased by less than 30%. The LPL synthesis, as judged by the incorporation of 35S-label into immunoprecipitable LPL, decreased at almost the same rate over the same time period as enzyme activity. The degradation rate was not significantly affected by IL-11/AGIF. These data suggest that regulation of the synthesis of the enzyme protein is at least one of the main steps in the suppression of LPL by IL-11/AGIF in 3T3-L1 adipocytes.
白细胞介素-11/脂肪生成抑制因子（IL-11/AGIF）可抑制脂肪生成，并抑制脂肪细胞中的脂蛋白脂肪酶（EC3.1.1.34，LPL）活性（1,2）。我们研究了IL-11/AGIF抑制3T3-L1脂肪细胞中LPL活性的机制。用50 ng/ml的IL-11/AGIF孵育脂肪细胞，8小时内LPL活性降低了75%，而LPL mRNA水平降低不到30%。通过将35S标记掺入可免疫沉淀的LPL来判断，LPL合成在与酶活性相同的时间段内以几乎相同的速率下降。降解速率未受到IL-11/AGIF的显著影响。这些数据表明，在3T3-L1脂肪细胞中，酶蛋白合成的调节至少是IL-11/AGIF抑制LPL的主要步骤之一。
