Regulation Effects Of Piper Longum.L And Piperine On Insulin Resistance Model In3T3-L1Adipocytes

Object:Insulin resistance (IR) is considered as a core component in the pathophysiology of the Type2diabetes mellitus (T2DM) and the other metabolic diseases such as fat, coronary heart disease, hyperlipidemia, high blood pressure and stroke. Previous study revealed that ethanol extract of Piper Longum. L.(EEPL) could regulate glucose and lipid metabolism and control blood pressure of IR model rats. In order to detect the improving effects of Piper Longum. L and piperine for IR,3T3-L1adipocytes were exposured with dexamethasone to induce IR cellular model. Then the effects of Extract of Piper Longum.L and piperine on this IR model were observed. Basing on the findings, the possible mechanism was also explored. It will be conducive to development of new drugs for improve the IR, which will provide some valuable reference about new methods and ideas from traditional medicine. It can extensively used as a perspective drug for prevention and treatment of T2DM.Methods:1EEPL and WEPL (water extract Piper Longum.L.) were extracted. The PIP concentration was detetermined by HPLC.2Cell culture of3T3-L1preadipocytes. Differentiated3T3-L1adipocytes of Intracellular fat accumulation was determined by oil red O staining.3Morphological changes in3T3-L1adipocytes were compared after exposured with luM dexamethasone (DEX) for24hours,48hours,96hours and120hours, respectively. The glucose (GLU) contents in cell culture supernatants were tested in order to evaluate the IR extent.4Effects of EEPL and PIP on the3T3-L1proliferation was determined by MTT assay. 5Effects of various concentrations of EEPL, WEPL and PIP in insulin resistance model were compared. Time-effect relationship was also investigated.Result:1PIP in0.0512-0.7168μg range showed a good linear relationship (r=0.9999), with the average recovery98.16%for EEPL and102.99%for WEPL.2Cell culture of3T3-L1preadipocytes:To prove the cultured3T3-L1preadipocytes was normal. The target pictures were compared with the released pictures of ATCC about3T3-L1preadipocytes. Oil red O staining revealed significantly that the formation of lipid droplets of Differentiated3T3-L1adipocytes.3Exposure to lμM Dex for24to120hours can significantly reduce the GLU contents in cell culture supernatants.on3T3-L1adipocytes (P<0.01).48h exposure is selected in our study.4Different concentrations of EEPL and PIP could significantly inhibited the proliferation of3T3-L1preadipocytes.5Exposure to various concentrations of treated groups time for24hours compared with the model control group, only EEPL can significantly reduce the GLU contents in cell culture supernatants of IR celluar model(P<0.05). Exposure to48hours, ROG, PIP, EEPL and WEPL all reduce the GLU contents in cell culture supernatants of IR celluar model(P<0.05). ROG and PIP in a dose-dependent manner.Conclusion:The proliferation of3T3-L1preadipocytes was significantly inhibited by different concentrations of EEPL and PIP. IR cellular model was induced successfully by exposuring3T3-L1adipocytes with lμM Dex (P<0.01). Exposured to various concentrations of treated groups for24hours, the IR was significantly improved by EEPL (P<0.05). Exposure to48hours, the IR was significantly improved by ROG, PIP, EEPL and WEPL (P<0.05). To improve the most obvious with concentration of20μg/ml of EEPL and WEPL.