Association of Polymorphisms in CAV1/CAV2 Locus with Type 2 Diabetes in Chinese Han Population / 中山大学学报(医学科学版)

[Objective]To study the association of CAV1/CAV2 gene polymorphisms with type 2 diabetes in Chinese Han population.[Methods]14 single nucleotide polymorphisms(SNPs)of CAV1/CAV2 gene were genotyped in 272 pa-tients with type 2 diabetes mellitus(T2DM group)and 287 subjects with normal glucose tolerance(control group)by ma-trix-assisted laser desorption ionization-time of flight-mass spectrometry(MALDI-TOF-MS).Waist circumference,body mass index,plasma glucose,serum insulin and lipid profiles were measured.Homeostatic model assessment of insulin resis-tance(HOMA-IR)and β-cell function(HOMA-β)were calculated.[Results]The minor allele frequency(MAF)distri-butions of CAV1 rs926198,CAV2 rs2270188,and rs1052990 were significantly different between T2DM group and con-trol group(P=0.008,0.021,and 0.045,respectively). After adjusting for age,gender,and BMI,logistic regression analysis showed that minor allele carriers(CC/CT genotype)of CAV1 rs926198 displayed a particularly increased risk of developing T2DM compared to major allele homozygotes(TT genotype)(OR=2.240,95% CI=1.415-3.544,P=0.001). GG/GA genotype carriers of CAV1 rs3807986 had lower odds for T2DM than that of AA genotype(OR=0.640,95% CI=0.449-0.913,P=0.014). Compared with TT genotype,GG/GT genotype of CAV2 rs2270188 was a protective factor for T2DM(OR=0.616,95% CI=0.432-0.878,P=0.007). Significant genotype association with T2DM was also identified in CAV2 rs1052990(GG/GT versus TT genotype:OR=0.658,95% CI=0.453-0.956,P=0.028). Multiple linear regression showed that minor allele C of SNP rs926198 was associated with an increased level of HOMA-IR(beta=1.010,P<0.001) and minor allele G of SNP rs2270188 was associated with a decreased level of HOMA-IR(beta=-0.379,P=0.023). No significant association was identified between any SNP and HOMA-β.Allele G of CAV1 rs3807986 and CAV2 rs2270188 were also associated with a decreased level of LDL-C(P=0.033 and 0.030,respectively).[Conclusion]CAV1/CAV2 locus might be the candidate genes for conferring susceptibility to T2DM in the Chinese Han population.SNP rs926198, rs3807986,rs2270188,and rs1052990 in CAV1/CAV2 locus were associated with T2DM risk perhaps through insulin resistance pathway.

Association of diabetes mellitus with biological behaviors of colorectal cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the association of diabetes mellitus(DM) with colorectal cancer.</p><p><b>METHODS</b>Case-control study was performed to compare 486 patients with colorectal cancer (study group) and 533 patients without colorectal cancer (control group) in the Affiliated Nanhai Hospital of Southern Medical University between 2006 and 2009.</p><p><b>RESULTS</b>The incidence of DM was 12.1% in study group and 7.1% in the control group, and the difference was significant(P<0.01). On multivariate analysis, DM was independently associated with colorectal cancer (OR=1.886,95% CI:1.450~3.571). Colorectal cancer risk was increased in DM patients with a duration of 5-20 years(P<0.05), while colorectal cancer risk in those with a duration less than 5 years or more than 20 years did not change(P>0.05). No significant differences in tumor differentiation, invasion depth, lymph node involvement, distant metastasis and lymphovascular invasion were found between colorectal cancer patients with and without DM(all P>0.05).</p><p><b>CONCLUSION</b>Diabetes mellitus increases the risk of colorectal cancer, however, biological behaviors of colorectal cancer is not associated with diabetes mellitus.</p>

Effects of leptin on RAAS and nitric oxide production in isolated rat glomeruli / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes in angiotensinogen (AGT), angiotensin II type 1 receptor (AT(1)R), endothelial nitric oxide synthase (eNOS) mRNA and protein expressions and nitric oxide (NO) content in the rat glomeruli in response to leptin stimulation.</p><p><b>METHODS</b>The glomeruli isolated from male SD rats were stimulated with 3 nmol/L leptin for 2 h. Real-time PCR and Western blotting were performed to analyze the mRNA and protein expressions of AGT, AT(1)R and eNOS in the glomeruli, and nitrite concentration in the glomeruli was measured by nitrate reductase assay.</p><p><b>RESULTS</b>In comparison with the control group, exposure to leptin increased the mRNA levels of AGT, ATR(1) and eNOS in the isolated glomeruli by 2.69-/+0.17, 3.77-/+0.16 and 2.56-/+0.29 folds (P=0.024, 0.018 and 0.044), and their protein levels by 2.06-/+0.10, 2.67-/+0.08 and 1.61-/+0.13 folds (P=0.021, 0.015 and 0.032), respectively. The NO production in the glomeruli was also increased by 2.77-/+0.14 folds (P=0.000) following leptin exposure.</p><p><b>CONCLUSION</b>Leptin exposure of isolated rat glomeruli directly causes activation of the internal renal renin-angiotensin system and enhanced NO production, suggesting that leptin plays a role in the pathogenesis of maladaptation in renal hemodynamics in obesity.</p>

Renal protective effects of sulodexide in diabetic rats and its anti-oxidative mechanism / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the renal protective effects of sulodexide and its anti-oxidative stress mechanism in diabetic rats.</p><p><b>METHOD</b>Thirty male SD rats were randomized into 3 equal groups, namely the control group, diabetic group, and sulodexide treatment group. Twelve weeks after establishment of rat diabetic models and administration of sulodexide, the rats were sacrificed for measurement of the urine volume, body mass, kidney mass/body weight ratio, plasma glucose, and glycosylated hemoglobin (HbA1c). Malondialdehyde (MDA) levels and superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-PX) activities in the renal tissue or serum were tested. Electron microscopy was performed to observe the pathological changes in the kidneys.</p><p><b>RESULTS</b>The urine volume, renal mass/body mass ratio, serum glucose, HbA1C, and serum and renal MDA levels all significantly increased in the diabetic rats in comparison with the normal controls (P<0.05). But the body weight and activities of SOD, CAT, and GSH-PX in the renal tissue in the normal control group were significantly higher than those in the diabetic and sulodexide group. After 12 weeks of sulodexide treatment, SOD, CAT, and GSH-PX activities in the renal tissue of rats were significantly increased in comparison with those in the diabetic rats (P<0.05). Electron microscopy showed obvious irregular thickening of the glomerular capillary basement membrane in the diabetic group with vacuolization in the mitochondria in the epithelial cells, and such pathological changes were significantly alleviated in the sulodexide treatment group.</p><p><b>CONCLUSIONS</b>Sulodexide can effectively lower the urinary albumin excretion rate, improve the ultrastructural renal pathologies and prevent glomerular basement membrane thickening in diabetic rats, probably in association with the reduction of the MDA levels and enhancement of SOD, CAT, and GSH-PX activities.</p>

Cost-effectiveness analysis on continuous subcutaneous insulin infusion and multi-point daily insulin injections in the treatment program of type 2 diabetes / 中华流行病学杂志

Objective To observe the cost-effectiveness of using continuous subcutaneous insulin infusion (CS Ⅱ) and multi-point daily insulin injections (MDI) in controlling blood sugar in the newly hospitalized type 2 diabetes patients. Methods Retrospective analysis on 86 cases taking CS Ⅱ and 103 cases using MDI on a 'blood sugar control program' among the newly hospitalized patients with type 2 diabetes. The period for observation was 2 weeks, using cost-effectiveness analysis methods to evaluate the two treatment programs. Results After two weeks of treatment, the effectiveness in the control of blood sugar in CS Ⅱ group was similar to the MDI group, with no significant difference(P<0.05) and the adverse reactions were similar. Costs in the CS Ⅱ program (Yuan/person) was less than in the MDI program (1478.34 vs. 1620.46), with significant differences (P< 0.05). The cost-effectiveness ratios (C/E) were 15.07 in the CS Ⅱ group, and 16.34 in the MDI group, with no significant difference (P>0.05). In order to further reduce the cost of CS Ⅱ group as a reference, the incremental cost-effectiveness ratio (△C/ △E)ofthe MDI group was 129.20. Conclusion Costs-effective of the CS Ⅱ program was better than the MDI one in treating the newly hospitalized patients with type 2 diabetes, suggesting that CS Ⅱ program might be a better choice for hospitals to carry on an intensive insulin therapy program.

Inadequate glycaemic control and antidiabetic therapy among inpatients with type 2 diabetes in Guangdong Province of China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Diabetes mellitus has become epidemic in recent years in China. We investigated the prevalence of hyperglycaemia and inadequate glycaemic control among type 2 diabetic inpatients from ten university teaching hospitals in Guangdong Province, China.</p><p><b>METHODS</b>Inadequate glycaemic control in diabetic patients was defined as HbA1c = 6.5%. Therapeutic regimens included no-intervention, lifestyle only, oral antiglycemic agents (OA), insulin plus OA (insulin + OA), or insulin only. Antidiabetic managements included monotherapy, double therapy, triple or quadruple therapy.</p><p><b>RESULTS</b>Among 493 diabetic inpatients with known history, 75% had HbA1c = 6.5%. Inadequate glucose control rates were more frequently seen in patients on insulin + OA regimen (97%) than on OA regimen (71%) (P < 0.001), and more frequent in patients on combination therapy (81% - 96%) than monotherapy (75%) (P < 0.05). Patients on insulin differed significantly from patients on OA by mean HbA1c, glycemic control rate, diabetes duration, microvascular complications, and BMI (P < 0.01).</p><p><b>CONCLUSIONS</b>This study showed that glycaemic control of type 2 diabetic patients deteriorated for patients who received insulin and initiation time of insulin was usually delayed. It is up to clinicians to move from the traditional stepwise therapy to a more active and early combination antidiabetic therapy to provide better glucose control.</p>

Comparison of continuous and discontinuous density gradient centrifugation for purification of human pancreatic islets / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the effect of continuous and discontinuous density gradient centrifugation for purification of human pancreatic islets with COBE 2991 cell processor.</p><p><b>METHODS</b>Human pancreases were obtained from brain-dead donors and stored in cold UW solution. The connective tissues were removed from the pancreases, and the pancreatic ducts were perfused with a cold enzyme (Liberase). The islets were then separated by gentle mechanical dissociation and purified with discontinuous (10 pancreases) or continuous (8 pancreases) gradients of HCA-Ficoll in COBE 2991 cell processor. Samples were collected in duplicate for determination of the quantity of islets, islet equivalents (IEQ), and the purity.</p><p><b>RESULTS</b>The weights of the pancreases before and after connective tissue removal and pancreas duct perfusion, and the quantity of islets obtained (including islets quantity of different diameters and total IEQ) after dissociation were not significantly different. Continuous gradient of HCA-Ficoll, compared with discontinuous gradient, resulted in significantly greater final islet quantity (55,000 IEQ vs 206,000 IEQ, P=0.000) and islet purity (58.0%-/+8.0% vs 33.5%-/+10.3%, P=0.000) and also greater number of islets with a diameter lager than 200 microm (P<0.01).</p><p><b>CONCLUSION</b>Continuous density gradient centrifugation can be more effective than discontinuous gradient in islet purification.</p>

Isolation and purification of human islet cells with semi-automated digestion / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish an semi-automated effective method for large-scale purification of islet cells from human pancreas.</p><p><b>METHODS</b>Human pancreas tissue was digested with collagenase P using a semi-automated pancreas-digestion system followed by purification in a HCA-Ficoll continuous gradient using Cobe2991 cell separator. After isolation, the islet cell yield and purity was evaluated with light microscope with DTZ staining, and the islet function assessed by insulin release assay in vitro.</p><p><b>RESULTS</b>The number of the islets collected from each pancreas averaged 38 6201-/+78 219 islet equivalents (IEQ) before purification, and 231 420-/+28 054 IEQ after the purification with discontinuous gradient centrifugation. From each gram of the pancreatic tissue, 3148-/+317 IEQ were obtained with an average purity of (62.81-/+2.68) %. The purified islets responded well to high-concentration (16.7 mmol/L) glucose stimulation with a 2.53-fold increase of insulin secretion over the basal level (3.3 mmol/l, P<0.001).</p><p><b>CONCLUSION</b>The established semi-automated method can be applicable for large-scale purification of fully functional islet cells from human pancreas.</p>

Comparison of once daily and twice daily administration of glimepiride with same total dosage in type 2 diabetes / 中华内分泌代谢杂志

A total of 126 patients with type 2 diabetes mellitus were randomized into two groups:one received glimepiride 1 mg twice daily and the other 2 mg once daily.Fasing blood glucose(BG),BG 2 h after meals(breakfast,lunch and dinner)and HbA_(IC)were tested,△and standard deviation of the 4 point BG were calculated.It was found that two kinds of administration of glimepiride were equally effective in decreasing BG and once daily aministration could ease better the fluctuation of BG.