ABSTRACT
Objective To analyze the islet ? cell function and the insulin resistance of different components of impaired glucose regulation(IGR).Methods A total of 463 adults diagnosed as IGR and 200 adults diagnosed as NGT by 75g OGTT,were included for the analysis of the islet beta cell function and insulin resistance.Results In the IFG group,HOMA-IR was significantly higher than in NGT and IGT group(P
ABSTRACT
Objective To investigate the effect of pancreatic ? cell dysfunction on abnormal glucose tolerance during Graves hyperthyroidism. Methods We investigated 6 healthy people and 36 Graves disease patients with abnormal glucose tolerance, and determined blood sugar and insulin at 0, 60 and 120 minutes after breakfast respectively. Then the HOMA-IR, HOMA-? and ISI were compared between the two groups. Results The HOMA-IR in the Graves disease patients with abnormal glucose tolerance is evidently higher than in the healthy subjects (P
ABSTRACT
OBJECTIVE:To study the therapic effect of soluble cluster of differentiation (sCD14) and soluble tumor necrosis factor receptor-P55(sTNFR-P55) on the inflammation,insulin resisitance and insulin secretion of serious scalded mice. METHODS: The lecels of mortality, peripheral white blood cell(WBC), Homeostasis Assessment-Insulin Resistance (HOMA-IR) and Homeostasis Assessmen-?(HOMA-?),fasting glucose, fasting lactic acid of the scalded mice treated individually by infusion with sCD14,sTNFR-P55,and both the sCD14 and sTNFR-P55, were examined compared with that of the control. RESULTS: The mortality of the scalded mice treated both by infusion with both of sCD14 and sTNFR-p55,were lower than that of the control(P
ABSTRACT
Objective To establish a pancreatic ?-cell developmet fish model with specific spatial expression patterns.Methods Molecular cloning,microinjection,whole embryo in-situ hybridization(WISH)and fluorescence microscopy in living were used to analyze of ?-cell development through generation of transgenic zebrafish.ResultsScreened and established pancreatic ? cells of transgenic zebrafish,and confirmed the fluorescence protein expression in the same spatiotemporal pattern with endogenous insulin gene to achieve dynamic monitoring islet ?-cell development situation in vivo.Conclusion The pancreatic ? cells of transgenic zebrafish animal model can successfully trace pancreatic ? cell development.
ABSTRACT
Insulin resistance and islet ? cell dysfunction are well-identified pathogenesis of type 2 diabetes. The generation of a great quantity of mitochondrial reactive oxygen species (ROS) impairs the function of mitochondria and induces oxidative stress during metabolic process of hyperglycaemia and hyperlipemia. Oxidative stress blocks insulin action pathway and induces insulin resistance; inhibit expression of insulin gene; decrease insulin secretion and impair ? cell function. In this paper, the mechanism of the ROS generation, insulin resistance and ? cell dysfunction induced by oxidative stress are reviewed.
ABSTRACT
Objective To establish the islet ? cell rat model by the ? cell-deleting technology.Methods Tweenty-four normal male SD rats and 12 weeks old were randomly divided into 3 groups,i.e,a normal diet group(NC,n=8),the model group 1(M1,n=8),and the model group 2(M2,n=8).The rats in M1 and M2 group were injected with 100 mg/kg and 150 mg/kg of streptozocin respectively.Five days later,the rats were sacrificed.The level of insulin(Ins)and Glucagon(Glc)in the pancreatic homogenate was measured.The tail of pancreas were obtained and fixed by Bolins liquid.Immunohistochemistry was performed to evaluate the expression of Ins and Glc in islet cells.Quantitative analysis was executed by image analyzer.Results Compared with the NC group,the total pancreas island areas of beta-cell deleting rats,M1 group and M2 group,are approximately 1/7 of normal control rats.Moreover,the percentages of beta-cell areas from total pancreas island areas decreased from 74.3% down to 5.4% and 5.2%,respectively.The Ins content in pancreas tissue homogenate of beta-cell deleting rats does not reach 3% of normal ones,While the Glc content unexpectedly increases.Less alpha cells distinguished by Glc positive dying through Immunohistochemistry are observed at periphery of pancreas islands of NC group.With beta cellsdeletion,the aggregation of alpha cells from periphery to centre of pancreas islands is found in M1 and M2 groups.Furthermore,the percentages of alpha cells area from total pancreas island areas are promoted from 16.4% to 76.5%、74.4%,respectively.Conclusion The islet ? cell rat model was established by injecting large dose STZ(100 mg/kg and 150 mg/kg).
ABSTRACT
Objective To investigate the effects of chronic hyperglycemia on the proliferation,secretion function and expression of endoplasmic reticulum stress(ERS) related molecules in pancreatic ? cell line MIN6. Methods MIN6 cells were treated with different concentrations of glucose(5.6,25 and 33.3mmol/L) and were harvested at indicated time(24h and 96h) for examinations.Cell proliferation was tested using CCK-8 solution,insulin and proinsulin secretion function was determined by ELISA,and mRNA expression of ERS related molecules(Total XBP-1,Spliced XBP-1) and protein expression of phosphorylated IRE1? were detected by Real-time PCR and Western blotting,respectively. Results After treatment with hyperglycemia for 96h, cell proliferation was significantly lower than that treated for 24h(P
ABSTRACT
Objective To observe the influence of taurine supplementation during early postnatal life on body weight and ultrastructure of islet ? cells in neonatal rats with low birth weight(LBW).Methods LBW neonatal rats were made by feeding 20%(C group) or 10%(R group) protein diet to fetal rats during gestation and lactation.Half of femal rats in group R were given a supplementation with 2.5% taurine drinking water(RT group) only during lactation,while other femal rats freely drunk.At postnatal day 1 and 21,the neonatal rats were weighted and their pancreas were removed.The ultrastructural changes of ? cells were observed by electron microscopy.Results At postnatal 21 days,the body weight of offsprings in group RT was significantly highter than that in group R(P=0.003);and the ultrastructure of ? cells in group RT got more improvement than that in group R.Conclusion Taurine supplementation can improve the growth-catch-up and the ultrastructure of islet ? cells of neonateal rats with LBW.
ABSTRACT
In this article we discuss the correlation between the functional defection of beta cell and its pathogenesis in traditional Chinese medicine;we summarize numbers of studies on Chinese medicine's effect on beta cell in different aspects through ways of experiment and clinical research,thus reflecting the unique effect of Chinese medicine in curing diabetes mellitus and improving the function of beta cell and at last proposing the direction of further study on this subject.
ABSTRACT
0.05);The levels of basal FINS showed a significant differences between group A and group B(P0.05).Conclusions Intensive insulin treatment to newly diagnosed type 2 diabetes patients can control blood glucose rapidly to a desired level,and can recover the function of B cell better than traditional oral hypoglycemic agents by dissolving the virulence of glucose rapidly.
ABSTRACT
Objective:To investigate the factors related to insulin resistance and islet ? cell secretory function in subjects with normal glucose tolerance(NGT).Methods:Insulin resistance and islet ? cell secretory function were estimated by Homeostasis Model Assessment in 2120 NGT subjects.Results:(1)ANOVA showed that there were significant differences in Homa-IR and Homa-? cell among different age groups(P
ABSTRACT
Objective To evaluate the effect of various kinds of dyslipidaemia on insulin resistance and pancreatic islet ? cell function in newly diagnosed type 2 diabetic patients. Methods 263 patients with newly diagnosed type 2 diabetes were divided into normal lipidemia group and dyslipidaemia group according to ATPⅢ standard. The dyslipidaemia group included 3 subgroups as the following: high TG group, high TC group, and mix group with high TG and TC. Homeostasis model assessment (HOMA) was applied to estimate insulin resistance (IR) and pancreatic islet ? cell function. Early insulin secretion index (EISI) and area under curve of insulin (AUCI) at all OGTT time points were calculated. Results Incidence of dyslipidaemia in the type 2 diabetic patients was 63%. BMI and WHR were significantly higher in both high TG group and mix group than in normal lipidemia group(P
ABSTRACT
0.05). Other indexes value are as follows: IR 1.1?0.3(NGT),1.3?0.6 (IGT) and 1.6?0.5 (DM), P
ABSTRACT
Objective To investigate the preventive effect of 1,25-dihydroxyvitamin D_3 〔1,25-(OH)_2D_3〕 on type 1 diabetes in cyclophosphamide-treated NOD mice. Methods Twenty female NOD mice were administered 280 mg/kg cyclophosphamide by a single intraperitoneal injection at the beginning of the experiment and then divided into two equal groups. Group 1 received intraperitoneal injection of 5 ?g/kg 1,25-(OH)_2D_3 every other day; Group 2 received the intraperitoneal injection of peanut oil in the same volume as control. When the experiment was finished on the 30th day, the incidence of diabetes and the degree of insulitis were observed. The expressions of bcl-2 and bax in islets were detected with immunohistochemical technique. The apoptosis rate of spleen T lymphocyte was also measured by flow cytometry quantitative analysis. Results Intraperitoneal injections of 1,25-(OH)_2D_3 to NOD mice reduced the incidence of diabetes (10% vs 70%, P
ABSTRACT
The islet secretion function in 42 clinically diagnosed diabetic ketosis and ketoacidosis pa- tients,aged 25～39 year-old,were studied.The results showed that the acute insulin responses to L-ARG (AIRarg) was significantly reduced in patients compared to control.As disease prolonged,AIRarg de- creased gradually.In the patients less than three months,the acute insulin responses to glucose(AIRglu) were markedly reduced,although the AIRarg were still sustained to some extent.The fasting blood insulin levels,in the patients more than three months were not different from controls,but C-peptide levels were significantly lower than those of controls.However,the C-peptide responses to L-ARG stimulation were not as evident as the insulin responses.The results suggested that impairment of the insulin secretion exist of in the early stage of DM,and exaggerated as the disease prolonged.Terapy of this type of diabetes mellitus de- pended mainly on insulin.
ABSTRACT
411 subjects were divided into six groups according to their FPG levels.And OGTT was carried out.Result showed that along with the FPG increasing, HOMA ?-cell index and ?I30 /?G30 were decreased progressively, and the fasting serum proinsulin level and ratio of proinsulin /insulin were increased markedly.The area under insulin curve decreased gradually when FPG was above 8 mmol/L. In conclusion, FPG is a reflection of islet ? cell function.
ABSTRACT
ATP-sensitive potassium channels (KATP channels) play important roles in various tissues tinder physiological and pathophysiological condi- conditions by coupling cell metabolic status to electrical activity. The KATP channel is a tetrameric complex of inwardly rectified potassium (Kir) and ATP binding protein (ABP). The Kir subunits form the channel pore, whereas ABP is required for activation and regulation. Both Kir and ABP are divided into different subunits and the various Kir and ABP subunits "mix and match" to form KATP channels with different pharmacological and nucleotide sensitivities. This review focuses on the molecular structure, physiological roles, pathophysiological and pharmacological proper ties of KATP channels in different tissues.
ABSTRACT
Systemic insulin resistance has been well known. Recently, an important question has been raised regarding whether islet cells are resistant to insulin (insulin resistance of ?, ? and ? cells) due to the discovery of insulin receptor and its downstream insulin signaling pathways in islet cells. As a new study field of insulin resistance, the elucidation to this issue is crucial for the new insight into the mechanisms of insulin resistance per se and type 2 diabetes.
ABSTRACT
AIM:To investigate the effect of high glucose toxicity on JNK pathway and cell function of INS-1 cells.METHODS: Cultured INS-1 cells with or without IGF-1 exposure,were treated with glucose at 3 concentrations (5.6 mmol/L,11.2 mmol/L and 33.3mmol/L),respectively. MTT was used to measure the cell viability. Apoptosis was determined by immuno-fluorescence and flow-cytometry analysis. The serine 270 phosphorylation of IRS and phosphorylation of JNK in INS-1 cells were detected in the presence or absence of SP600125 treatment.RESULTS: The cell viability decreased and apoptosis increased with elevated glucose concentrations. The percentage of apoptosis cells was 11.3% in 5.6 G group,12.7% in 11.2 G group and 28.2% in 33.3 G group. There was remarkable increase in apoptosis in 33.3 G group with a 2.49-fold increase to the cells in the basal 5.6 mmol/L glucose. High glucose activated the serine 270 phosphorylation of IRS correlates with JNK phosphorylation in INS-1 cells. Using Western blotting analysis,the levels of JNK phosphorylation were 3.33 fold increased and serine 270 phosphorylation of IRS was 1.17 fold increased in 33.3 G group compared to 11.2 G group (P