The Effect Of Signal Transduction Pathway Of GLUT4and Evidence-based Research By Jiangtang Sanhuang Tablet On Diabetic Rats

Partl:Literature researchIn recent years, the global incidence of diabetes was growing rapidly year after year, threatening human health. The pathogenesis of diabetes is complicated, which is not entirely clear now. But we know insulin resistance is the important pathogenesis, particularly insulin signal transduction pathway abnormality. Improving abnormal insulin signaling pathway will be bound to improve insulin resistance and to reach the therapeutic aim. As one of the measures of preventing and treating diabetes and its complications, Chinese medicine has its unique advantages. The recognition of diabetes, namely Xiaoke disease in traditional Chinese medicine, goes back to ancient times. There were records of Xiaoke diseases as early as in 《The Yellow Emperors Internal Classic》. Ancient physicians, later scholars also accumulated rich experience in the treatment of Xiaoke diseases. Through summing up and analyzing ancient and modern literature, we summarized the main pathogenesis of Xiaoke diseases are "deficiency", particularly "Qi-deficiency","Yin-deficiency", and "heat","blood stasis". So tonifying Qi and nourishing Yin combined with purging heat and dispersing blood stasis will treat Xiaoke diseases effectively. Jiangtang Sanhuang Tablet is based on experience of Professor Xiong Manqi in our school, which was established according to dialectical points of diabetes, namely Qi and Yin deficiency, blood stasis and heat accumulation. Its use and research have been more than twenty years, confirming the exact effect. Today, we want to observe its other effects on diabetic rats, also to increase the strength of its evidence-based treatment of evidence.Part2:Experiment researchObjectiveOur purpose is to observe the effects of GLUT4and the key signaling protein of PI3-k/Akt and CAP signal path which regulate the transposition of GLUT4in skeletal muscle, and the effects of GFAT which is limiting enzymes in hexosamie biosynthesis pathway by Jiangtang Sanhuang Tablet on diabetic rats, and then to expound the mechanism of enhancing the function of skeletal muscle in diabetes by Jiangtang Sanhuang Tablet, and to provide a new explanation of enhancing insulin sensitivity.MethodsAccording to body weight,70SPF SD rats were randomly divided into normal group(n=8) and model group(n=62), both with adaptable feed for1week, which were kept in separate cages with the same sex. Randomly select20rats from model group to have preliminary experiment of establishing type Ⅱ diabetic model. After fasting12hours, the model group were given streptozocin(STZ)(35mg/kg) by intraperitoneal injection one time, normal group were given citrate salt buffer in the same way. After72hours they were type Ⅱ diabetic rats with fasting blood glucose≥16.7mmol/l. At the same time observe the blood sugar and deaths of rats. On alternate day, the rest rats in model group were given STZ(30mg/kg) by intraperitoneal injection one time. According to the blood sugar, type Ⅱ diabetic rats were randomly divided into type Ⅱ diabetic model group(n=11, dose:equal amount of drinking water), Jiangtang Sanhuang Tablet group(n=12, dose:0.675g/kg/d), tonifying Qi and nourishing Yin group(n=11, dose:6.48g/kg/d). The course of treatment lasted for8weeks. All rats were fed normal diet of clean grade between before and after establishing diabetic model. During the experiment all rats take food and water freely. After8weeks treatment,30rats were left. The number of normal group was left8, type Ⅱ diabetic model group was7, Jiangtang Sanhuang Tablet group was8, tonifying Qi and nourishing Yin group was7. Rats were tested blood glucose after induced STZ72hours, before dosing, after dosing for4weeks and8weeks. Weight all rats before using STZ, dosing for4weeks and8weeks. Fasting serum insulin, glycated hemoglobin, cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein were tested after8weeks. GLUT4, CAP, GFAT mRNA in skeletal muscle were tested by RT-PCR and GLUT4, PI3-k p85α, Aktl by Western blot.ResultsAfter4weeks treatment, compared with type Ⅱ diabetic model group, Jiangtang Sanhuang Tablet group could reduce the loss of weight (P<0.05), but tonifying Qi and nourishing Yin group could not(P>0.05); compared with type Ⅱ diabetic model group, both Jiangtang Sanhuang Tablet group and tonifying Qi and nourishing Yin group could lower blood sugar(P<0.01); compared with tonifying Qi and nourishing Yin group, Jiangtang Sanhuang Tablet group could not reduce the loss of weight and lower blood sugar (P>0.05). After8weeks treatment, compared with type Ⅱ diabetic model group, both Jiangtang Sanhuang Tablet group and tonifying Qi and nourishing Yin group could increase the protein expression of PI3-k p85a and the expression of CAP mRNA in skeletal muscle, increase fasting serum insulin, lower blood sugar and glycated hemoglobin, and reduce the loss of weight (P<0.05); Jiangtang Sanhuang Tablet group could increase the expression of GLUT4mRNA and the protein expression of GLUT4and Aktl in skeletal muscle, increase high-density lipoprotein and insulin sensitivity index, decrease the expression of GFAT mRNA, and lower cholesterol, triglycerides, and low-density lipoprotein(P <0.05), but tonifying Qi and nourishing Yin group could not (P>0.05). Compared with tonifying Qi and nourishing Yin group, Jiangtang Sanhuang Tablet group could neither reduce the loss of weight nor increase insulin sensitivity index(P>0.05), but could increase the expression of GLUT4, CAP mRNA and the protein expression of PI3-k p85a, Aktl and GLUT4in skeletal muscle, increase high-density lipoprotein, fasting serum insulin, decrease the expression of GFAT mRNA, and lower cholesterol, triglycerides, low-density lipoprotein, blood sugar and glycated hemoglobin(P<0.05). Compared with the self4weeks treatment, Jiangtang Sanhuang Tablet group could continuously lower blood sugar (P<0.05), but tonifying Qi and nourishing Yin group could not(P>0.05).ConclusionJiangtang Sanhuang Tablet could decrease the expression of GFAT mRNA, increase fasting serum insulin to increase the expression of CAP mRNA and the protein expression of PI3-k p85a and Aktl, the expression of GLUT4mRNA and the protein expression of GLUT4, and then to lower blood sugar, glycated hemoglobin and the loss of weight; increasing the gene and protein expression of insulin signaling pathway further increase insulin sensitivity index, improve glucose metabolism, regulate lipid metabolism; regulating lipid metabolism further protect islet β-cells, inhibit glycosylation reaction, improve insulin resistance to control blood sugar effectively. These make multi-targets effects of Jiangtang Sanhuang Tablet get the synergies and the best treatment effects. Compared with tonifying Qi and nourishing Yin group, Jiangtang Sanhuang Tablet group could continuously lower blood sugar through a multi-target way.Part3:Evidence-based researchObjectiveTo assess the effects with Jiangtang Sanhuang Tablet and Modified Taohe Chengqi Decoction for replenishing qi and nourishing yin, purging heat and dispersing blood stasis in diabetic animal models through a systematic review.MethodsTo search databases by computer, and dissertation database of library of Guangzhou university of Traditional Chinese Medicine by hand. According to the inclusion and exclusion criteria to choose experiments, assess the qualities, extract the data, and analyze the data with RevMan5.1software and Stata11.0software by two researchers independently. The data which can not be merged were analyzed by descriptive study.ResultsGetting fifteen experiments, according to ARRIVE handbook, all experiments were described comprehensively. Compared with normal groups, all detected indexes in type Ⅱ diabetic model group were statistically significant (P<0.05), each model has characteristics of diabetes. Compared with type Ⅱ diabetic model group, Modified Taohe Chengqi Decoction group could lower fasting serum glucagon(P<0.01); both Jiangtang Sanhuang Tablet group and Modified Taohe Chengqi Decoction group could lower blood sugar, cholesterol and the loss of weight, increase insulin sensitivity index (P<0.01); neither Jiangtang Sanhuang Tablet group nor Modified Taohe Chengqi Decoction group could decrease glycated hemoglobin, low-density lipoprotein, and increase high-density lipoprotein(P>0.05). Subgroup analysis showed Modified Taohe Chengqi Decoction group could decrease daily water consumption, daily food intake and daily urine output (P<0.01), but Jiangtang Sanhuang Tablet group could not(P>0.05); Jiangtang Sanhuang Tablet group could increase fasting serum insulin and lower triglycerides(P<0.01), but Modified Taohe Chengqi Decoction group could not(P>0.05). Research of protecting target organ showed Modified Taohe Chengqi Decoction group could protect artery, heart, kidney and pancreas; Jiangtang Sanhuang Tablet group could protect liver, and small intestine. Meta analysis also showed Jiangtang Sanhuang Tablet group could protect kidney by decreasing the expression of TGF-β1in kidneys, relative kidney weight, serum creatinine and24hours urinary protein(P<0.05), without decreasing urea nitrogen(P>0.05). Sensitivity analysis showed different models and drugs are the important causes of heterogeneity between experiments; both Jiangtang Sanhuang Tablet group and Modified Taohe Chengqi Decoction group could lower blood sugar, and increase fasting serum insulin(P<0.01); Jiangtang Sanhuang Tablet group could reduce the loss of weight (P<0.01). Cumulative meta-analysis showed both Jiangtang Sanhuang Tablet group and Modified Taohe Chengqi Decoction group could lower blood sugar well since1999; research of large sample made the results more reliable and stable. Funnel plot, Begg’s test and Eegg’s test indicated publication bias among thirteen experiments about fasting plasma glucose (P<0.01).ConclusionBoth Jiangtang Sanhuang Tablet and Modified Taohe Chengqi Decoction for replenishing qi and nourishing yin, purging heat and dispersing blood stasis could lower blood sugar, increase insulin sensitivity index and relieve some of symptoms through a multi-target way, prevent and treat diabetes complications through a multi-pathway and multi-location way. Publication bias test of thirteen experiments in the including fifteen experiments increased publication bias undoubtedly. Given that publication bias are unavoidable in meta analysis, this systematic review of animal experiment could yet be regarded as the reference of further carrying out the research of diabetes and its complications and getting the high-quality evidence of evidence-based medicine.