The Effects Of U937 Macrophages On The Glucose And Lipid Metabolism,Proliferation And Apoptosis Of SW872 Cells

PartⅠThe differention of SW872 preadipocytes and the co-cultrue of U937 macrophagesObjectiveTo study the differentiation effect of oleic acid on SW872 preadipocytes, established the model of mature adipocytes and co-cultured of U937macrophages model.MethodsSW872 preadipocytes were cultured and induced to differentiate by 0.6mM oleic acid in vitro. The morphologic changes of SW872 cells were observed during the progress of differentiation. Fat droplets were observed in the cytoplasm by Oil red O staining .Triglyceride (TG) mass was detected by chemical colorimetry methodsResults1. SW872 preadipocytes were fibroblastic, and no fat droplet was noted in cytoplasm. 24 h after stimulated by oleic acid , The cells became bigger, rounder and contained numerous small lipid-filled inclusions. The differentiation was found in most all cells and the bulk of the cytoplasm was filled lipid storage droplets 48 h after oleic acid stimulation . More and more fat drops were accumulated in these cells with time pass. Seventy-two hours after differentiation, SW872 preadipocytes differentiated into mature adipocytes with lots of fat droplets in the cells, which became more bigger and rounder . 2. Comparing with that of before differentiation, TG mass was significantly increased 24 h after oleic acid stimulation (P<0.05). The concentration of TG mass was increased up to 14 fold 72 h after the differentiation induction, (P<0.01).ConclusionThese observations suggested that SW872 preadipocytes could be induced to differentiate into typical mature adipocytes by 0.6 mM oleic acidPartⅡThe roles of Macrophage inflammation in the insulin resistance of SW872 AdipocytesObjective: The purpose of the present study was to explore the roles of macrophage in the insulin resistance of adipocytes by examining the effect of inflammatory stress and hyperlipidemia on the glucose transport of adipocytes.METHODS:Following the exposure of SW872 preadipocytes to oleate at different concentrations, the level of TNF-α,MCP-1 secretion and Visfatin gene expression were evaluate by ELISA and RT-PCR methods. The glucose transport rate was assessed as [3H]-2-deoxy glucose up take. Furthermore, the SW872 preadipocytes and adipocytes were co-cultrued with the U937 macrophage. The inflammatory marks and glucose transport rate was examined as above.RESULTS:Oleat increased the glucose transport in SW872 preadipocytes and adipocytes at the concentration of 0mmol/L to 0.6mmol/L stimulation. But over the 0.8mmol/L exposure to oleat, downregulation of glucose transport was observed. The level of TNF-α,MCP-1 secretion and Visfatin gene expression were rised with increasing oleat concentrations. After the co-culture with the U937 macrophage, the all inflammatory marks were further increased, but the glucose transport rate was inhibited.CONCLUSION:The adiposity's differentiation and maturation were induced by the oleat. At the stress of high fatty acids, it's not only weakened the glucose transport, but also results in the inflammatory marks increased. The co-cultuer of macrophage aggravated the inflammatory state and insulin sensitivity.PartⅢThe Effects of U937 Macrophage on the Proliferation and Apoptosis of SW872 AdipocytesObjective The purpose of the present study was to explore the roles of macrophage in pathophysiology of adipocytes by examining the proliferation and apoptosis of SW872 adipocytes co-cultrued with the U937 macrophage.Methods : Following the exposure of SW872 preadipocytes to oleate at different concentrations, the level of TNF-α,MCP-1 secretion were evaluate by ELISA methods. The proliferation and apoptosis of adipocytes was assessed by the methyl thiazolyl tetrazolium method (MTT) and Flow Cytometry. Furthermore, the SW872 preadipocytes and adipocytes were co-cultrued with the U937 macrophage. The inflammatory marks and proliferation and apoptosis of adipocytes was examined as above.Results: The level of TNF-α,MCP-1 secretion were rised with the elevation oleat concentrations and the differentiation of adipocytes. Meanwhile, the apoptosis of adipocytes increased(P<0.05). After the co-culture with the U937 macrophage, all inflammatory marks further increased. But the apoptosis of adipocytes were not influnced(P>0.05). The proliferation of SW872 preadipocytes were significantly inhibited by the macrophage co-culture(P<0.05).Conclusions The adiposity's differentiation and maturation were induced by the oleat. With the stress of high fatty acids, the inflammatory state and apoptosis of adipocytes worsening. The chemoattractant of macrophage aggravated the inflammatory state and aggravated the proliferation of preadipocytes.