Chiadak Jeanne Durendale, Arsenijevic Tatjana, Gregoire Francoise, Bolaky Nargis, Delforge Valerie, Perret Jason, Delporte Christine
Laboratory of Pathophysiological and Nutritional Biochemistry, Université Libre de Bruxelles, 1070 Brussels, Belgium.
Department of Biochemistry, Faculty of Sciences, University of Dschang, 67 Dschang, Cameroon.
Int J Mol Sci. 2016 Oct 18;17(10):1742. doi: 10.3390/ijms17101742.
Aquaglyceroporins, belonging to the family of aquaporins (AQPs), are integral plasma membrane proteins permeable to water and glycerol that have emerged as key players in obesity. The aim of this study was to investigate the expression profile of AQPs in undifferentiated and differentiated 3T3-L1 cells and to investigate the changes in expression of aquaglyceroporins in 3T3-L1 cells differentiated into adipocytes and subjected to lipopolysaccharide (LPS) mimicking inflammation occurring during obesity. Furthermore, the study aimed at identifying the signaling cascade involved in the regulation of aquaglyceroporins expression upon LPS stimulation. 3T3-L1 cells were grown as undifferentiated cells (UDC; preadipocytes) or cells differentiated into adipocytes (DC, adipocytes). DC were incubated in the presence or absence of LPS with or without inhibitors of various protein kinases. AQPs mRNA expression levels were measured by real-time quantitative polymerase chain reaction (RT-qPCR). AQP1, AQP2, AQP3, AQP9 and AQP11 mRNA were expressed in both UDC and DC, whereas AQP4, AQP7 and AQP8 mRNA were expressed only in DC. In DC, LPS up-regulated AQP3 mRNA levels ( < 0.05) compared to control; these effects were inhibited by CLI095, SP600125 and BAY11-7082 ( < 0.05). LPS decreased both AQP7 and AQP11 mRNA levels ( < 0.01) in DC as compared to control; this decrease was inhibited by CLI095 and BAY11-7082 ( < 0.05) and additionally by SP00125 for AQP7 ( < 0.05). SB203580 had no effect on LPS-induced AQP3, AQP7 and AQP11 mRNA levels modulations. In conclusion, our results clearly show that many AQPs are expressed in murine 3T3-L1 adipocytes. Moreover, in DCs, LPS led to decreased AQP7 and AQP11 mRNA levels but to increased AQP3 mRNA levels, resulting from the Toll-like receptor 4 (TLR4)-induced activation of JNK and/or NFκB pathway.
水甘油通道蛋白属于水通道蛋白（AQP）家族，是整合在质膜上的蛋白质，可通透水和甘油，已成为肥胖中的关键因子。本研究旨在调查水通道蛋白在未分化和分化的3T3-L1细胞中的表达谱，并研究3T3-L1细胞分化为脂肪细胞并受到模拟肥胖期间发生的炎症的脂多糖（LPS）刺激后水甘油通道蛋白表达的变化。此外，该研究旨在确定LPS刺激后参与调节水甘油通道蛋白表达的信号级联反应。3T3-L1细胞作为未分化细胞（UDC；前脂肪细胞）或分化为脂肪细胞的细胞（DC，脂肪细胞）进行培养。DC在有或无LPS以及有或无各种蛋白激酶抑制剂的情况下孵育。通过实时定量聚合酶链反应（RT-qPCR）测量水通道蛋白的mRNA表达水平。AQP1、AQP2、AQP3、AQP9和AQP11的mRNA在UDC和DC中均有表达，而AQP4、AQP7和AQP8的mRNA仅在DC中表达。在DC中，与对照组相比，LPS上调了AQP3的mRNA水平（<0.05）；这些作用被CLI095、SP600125和BAY11-7082抑制（<0.05）。与对照组相比，LPS降低了DC中AQP7和AQP11的mRNA水平（<0.01）；这种降低被CLI095和BAY11-7082抑制（<0.05），对于AQP7，SP00125也有额外的抑制作用（<0.05）。SB203580对LPS诱导的AQP3、AQP7和AQP11的mRNA水平调节没有影响。总之，我们的结果清楚地表明，许多水通道蛋白在小鼠3T3-L1脂肪细胞中表达。此外，在DC中，LPS导致AQP7和AQP11的mRNA水平降低，但导致AQP3的mRNA水平升高，这是由Toll样受体4（TLR4）诱导的JNK和/或NFκB途径激活所致。
