Research On The Effect Of Berberine Catalpol And Their Combination Relieving IR

ObjectiveWe observed and compared the effect of berberine catalpol and their combination on glucose uptake and utilization of insulin resistant (IR) adipocytes, as well as the effect on proliferation, differentiation, PPARγmRNA expression and lipid accumulation of preadipocytes,in order to investigate the scientific connotation of Rhizoma Coptidis Pill through methods of pharmacodynamics and pharmacology, and its difference with PPARγactivator in relieving insulin resistance.MethodsPart one Effect of Berberine Catalpol and Their Combination on IR 3T3-L1 AdipocytesAdipocyte IR model was induced with dexamethasone, and diveded into model group, treatment groups (rosiglitazone group, berberine group, catalpol group, berberine+catalpol group). Normal group was also designed. Cells were incubated in corresponding medicine with or without10nmol/L insulin for 48 hours. Glucose consumption was assayed with glucose oxidase method; glucose transport with measuring the uptake of [3H]2-DG. Part two Effect of Berberine Catalpol and Their Combination on 3T3-L1 Predipocyte Proliferation and Differentiation1. Effect of berberine catalpol and their combination on 3T3-L1 preadipocyte proliferationPreadipocytes was cultured and divided into rosiglitazone group, berberine group, catalpol group, berberine+catalpol group, and control group until 70% confluence. Preadipocytes proliferation was determined by MTT spectrophotometry.2. Effect of berberine catalpol and their combination on 3T3-L1 preadipocyte metabolism and differentiationPreadipocytes was cultured, differentiated into mature adipocytes, and then divided into rosiglitazone group, berberine group, catalpol group, berberine+catalpol group, as well as control group. Glucose consumption of cells incubated with corresponding medicine was assayed with glucose oxidase method; Cell differentiation phase was detected by oil red O staining; PPARγmRNA expression was tested with RT-PCR.ResultsPart one Effect of Berberine Catalpol and Their Combination on IR 3T3-L1 Adipocytes1. Effect of berberine, catalpol and their combination on IR 3T3-L1 adipocytes glucose consumptionWith or without 10nmol/L insuline, glucose consumption of model group was significantly lowered after 48 hours of treatment (P<0.01); and glucose consumption of berberine group, catalpol group and combination group were significantly improved compared with the model (P<0.01). The effect of rosiglitazone was better with the exitance of insulin, while the effect of Chinese drugs was significant with or without insulin. Besides, the effect of combination group was better than single drug group (P <0.01).2. Effect of Berberine, Catalpol and their combination on IR 3T3-L1 adipocytes glucose tansportationWith or without 10nmol/L insuline, glucose transportation of model group was significantly lowered after 48 hours of treatment (P<0.01); and glucose transportation of berberine group, catalpol group and combination group were significantly improved compared with the model (P<0.01). The effect of rosiglitazone was better with the exitance of insulin, while the effect of Chinese drugs was significant with or without insulin. Besides, the effect of combination group was better than single drug group (P<0.01).Part two Effect of Berberine, Catalpol and Their Combination on 3T3-L1 Preadipocyte Proliferation and Differentiation1. Effect of berberine catalpol and their combination on 3T3-L1 preadipocyte proliferationCompared with the control, the MTT value of preadipocytes increased in berberine group (P<0.05), and the difference was insignificant in combination group, catalpol group and rosiglitazone group.2. Effect of berberine catalpol and their combination on 3T3-L1 preadipocyte metabolism and differentiationBerberine, catalpol as well as their combination enhanced glucose consumption in 3T3-L1 adipocytes significantly. The lipid accumulation in berberine treated group was lowered markedly in caparison with the control group (P<0.01), whereas the result is significantly increased in rosiglitazone group (P<0.01), and insignificant in catalpol group.3. Effect of berberine catalpol and their combination on insulin resistant 3T3-L1 adipocytes PPARγmRNA expressionCompared with the control, PPARγmRNA expression was up-regulated in rosiglitazone group (P<0.01), down-regulated in berberine group and combination group (P<0.05,P<0.01), and the difference was insignificant in catalpol group.Conclusion1. Both berberine and catalpol can increase glucose consumption and transport, the actions are independent of insulin, which indicate the two Chinese hebal drug extracts might be able to treat insulin resistance. Besides, the effect of combination group was better than single drug groups, which proved the science in coptidis rhizoma pills.2. Berberine promotes the proliferation of 3T3-L1 preadipocytes, down-regulates the expression of PPARγmRNA and inhibits the accumulation of lipid drops; catalpol does not inhance adipocyte differentiation; combination of the two drugs could also decrease lipid accumulation in cells, which suggested that these two medicines may relieving IR in a manner different from rosiglitazone.