Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “T2DM”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 415 records · Page 23Linked to original sources

Differences in expression of cardiovascular risk factors among type 2 diabetes mellitus patients of different age.

Atherosclerotic coronary heart disease and other forms of cardiovascular disease (CVD) are the major cause of mortality in type II diabetes (T2DM) as well as a major contributor to morbidity and lifetime costs. The purpose of this article is the identification of the biochemical parameters in plasma, which may serve as predisposition factors to CVD in T2DM patients of different ages. The variability of hyperglycemia, dyslipidemia, and inflammation with age progression was also studied for comparison. Four different diabetic groups allocated on the basis of the subjects' age (Group A: 15-25 years old; Group B: 26-40 years old; Group C: 40-60 years old; Group D: 60-80 years old) and consisting of 10 patients each, in parallel with 10 healthy controls matched for age, sex, and ethnic origin were screened for glucose, insulin, lipid profile (total cholesterol, triglycerides, LDL, and HDL), and inflammatory mediators (CRP, IL-6, and TNF-alpha). Significant differences were observed among the expressions of biochemical markers among different age groups. Hyperglycemia showed no variability with age whereas dyslipidemia correlated positively with age progression, as well as obesity, low physical activity, and family history of heart disease or diabetes. Marked inflammation was prominent only in Groups C and D. This article indicates that different biochemical parameters may be used for the assessment of CVD risk in T2DM patients of variable age.

Adolescent↗

Inflammation in metabolic syndrome and type 2 diabetes: Impact of dietary glucose.

Chronic overnutrition combined with a lack of exercise is the main cause for the rapidly increasing prevalence of overweight and obesity. It seems accepted that adipositis (macrophage infiltration and inflammation of adipose tissue in obesity) and systemic low grade inflammation affect the pathogenesis of the metabolic syndrome or type 2 diabetes mellitus (T2DM). Therefore, modern weight reduction programs additionally focus on strategies to attenuate the inflammation state. Exercise is one major factor, which contributes to the reduction of both the incidence of T2DM and inflammation, and the immunomodulatory effects of exercise are supported by similarly beneficial effects of dietary changes. In this context, glucose is the most extensively studied nutrient and current investigations focus on postprandial glucose-induced inflammation, one possible reason why hyperglycemia is detrimental. Indeed, glucose may modulate the mRNA expression and serum concentrations of immune parameters but these alterations rapidly normalize in normoglycemic subjects. In case of an impaired metabolic state, however, postprandial hyperglycemia increases magnitude and duration of systemic inflammatory responses, which probably promotes the development of T2DM and of cardiovascular disease.

Cytokines↗

Free fatty acids and cytokines induce pancreatic beta-cell apoptosis by different mechanisms: role of nuclear factor-kappaB and endoplasmic reticulum stress.

Apoptosis is probably the main form of beta-cell death in both type 1 diabetes mellitus (T1DM) and T2DM. In T1DM, cytokines contribute to beta-cell destruction through nuclear factor-kappaB (NF-kappaB) activation. Previous studies suggested that in T2DM high glucose and free fatty acids (FFAs) are beta-cell toxic also via NF-kappaB activation. The aims of this study were to clarify whether common mechanisms are involved in FFA- and cytokine-induced beta-cell apoptosis and determine whether TNFalpha, an adipocyte-derived cytokine, potentiates FFA toxicity through enhanced NF-kappaB activation. Apoptosis was induced in insulinoma (INS)-1E cells, rat islets, and fluorescence-activated cell sorting-purified beta-cells by oleate, palmitate, and/or cytokines (IL-1beta, interferon-gamma, TNFalpha). Palmitate and IL-1beta induced a similar percentage of apoptosis in INS-1E cells, whereas oleate was less toxic. TNFalpha did not potentiate FFA toxicity in primary beta-cells. The NF-kappaB-dependent genes inducible nitric oxide synthase and monocyte chemoattractant protein-1 were induced by IL-1beta but not by FFAs. Cytokines activated NF-kappaB in INS-1E and beta-cells, but FFAs did not. Moreover, FFAs did not enhance NF-kappaB activation by TNFalpha. Palmitate and oleate induced C/EBP homologous protein, activating transcription factor-4, and immunoglobulin heavy chain binding protein mRNAs, X-box binding protein-1 alternative splicing, and activation of the activating transcription factor-6 promoter in INS-1E cells, suggesting that FFAs trigger an endoplasmic reticulum (ER) stress response. We conclude that apoptosis is the main mode of FFA- and cytokine-induced beta-cell death but the mechanisms involved are different. Whereas cytokines induce NF-kappaB activation and ER stress (secondary to nitric oxide formation), FFAs activate an ER stress response via an NF-kappaB- and nitric oxide-independent mechanism. Our results argue against a unifying hypothesis for the mechanisms of beta-cell death in T1DM and T2DM.

Animals↗

Palmitate induced mitochondrial deoxyribonucleic acid damage and apoptosis in l6 rat skeletal muscle cells.

A major characteristic of type 2 diabetes mellitus (T2DM) is insulin resistance in skeletal muscle. A growing body of evidence indicates that oxidative stress that results from increased production of reactive oxygen species and/or reactive nitrogen species leads to insulin resistance, tissue damage, and other complications observed in T2DM. It has been suggested that muscular free fatty acid accumulation might be responsible for the mitochondrial dysfunction and insulin resistance seen in T2DM, although the mechanisms by which increased levels of free fatty acid lead to insulin resistance are not well understood. To help resolve this situation, we report that saturated fatty acid palmitate stimulated the expression of inducible nitric oxide (NO) synthase and the production of reactive oxygen species and NO in L6 myotubes. Additionally, palmitate caused a significant dose-dependent increase in mitochondrial DNA (mtDNA) damage and a subsequent decrease in L6 myotube viability and ATP levels at concentrations as low as 0.5 mM. Furthermore, palmitate induced apoptosis, which was detected by DNA fragmentation, caspase-3 cleavage, and cytochrome c release. N-acetyl cysteine, a precursor compound for glutathione formation, aminoguanidine, an inducible NO synthase inhibitor, and 5,10,15,20-tetrakis(4-sulphonatophenyl) porphyrinato iron (III), a peroxynitrite inhibitor, all prevented palmitate-induced mtDNA damage and diminished palmitate-induced cytotoxicity. We conclude that exposure of L6 myotubes to palmitate induced mtDNA damage and triggered mitochondrial dysfunction, which caused apoptosis. Additionally, our findings indicate that palmitate-induced mtDNA damage and cytotoxicity in skeletal muscle cells were caused by overproduction of peroxynitrite.

Adenosine Triphosphate↗

Common variants in glutamine:fructose-6-phosphate amidotransferase 2 (GFPT2) gene are associated with type 2 diabetes, diabetic nephropathy, and increased GFPT2 mRNA levels.

Increased flux of glucose through the hexosamine biosynthetic pathway has been implicated in insulin resistance, altered insulin secretion, and diabetic nephropathy. Glutamine:fructose-6-phosphate amidotransferase (GFPT), the rate limiting enzyme in hexosamine biosynthesis, is encoded by the unlinked but highly homologous genes GFPT1 and GFPT2. We tested the hypothesis that GFPT2 sequence variation contributed to the susceptibility to type 2 diabetes mellitus (T2DM) and diabetic nephropathy in Caucasian and African-American individuals. We identified 11 single nucleotide polymorphisms (SNPs), of which seven were common. A single variant in exon 14, I471V, altered the amino acid sequence, is conserved between human and mouse genes, and was associated with T2DM among Caucasians (P = 0.05). A trend to an association was noted with diabetic nephropathy among African-American individuals (P = 0.15). Several variants in the 3' untranslated region (UTR) and exon 18 were also associated with T2DM in Caucasian individuals (P < 0.05), and the SNP in the 3' UTR was associated with diabetic nephropathy in African-American subjects (P = 0.047). GFPT2 mRNA levels in transformed lymphocytes from study subjects were significantly increased among African-American subjects compared with Caucasian individuals, regardless of diagnosis. Furthermore, the associated allele of the 3' UTR SNP was approximately 2-fold overexpressed. We propose that the 3' UTR variant results in increased GFPT2 mRNA levels with resultant increased hexosamine flux. The I471V variant may contribute to altered protein function or may simply be in linkage disequilibrium with the 3' UTR.

3' Untranslated Regions↗

Effect of pioglitazone on circulating adipocytokine levels and insulin sensitivity in type 2 diabetic patients.

We examined the effect of pioglitazone (PIO) on circulating adipocytokine levels to elucidate the mechanisms by which thiazolidinediones improve insulin resistance in type 2 diabetes mellitus (T2DM). Twenty-three subjects with T2DM (age 54 +/- 2 yr, body mass index 29 +/- 1 kg/m(2)) were randomly assigned to receive placebo (n = 11) or PIO, 45 mg/d (n = 12), for 4 months. Before and after treatment, subjects received a 75-g oral glucose tolerance test (OGTT); euglycemic insulin clamp (40 mU/m(2).min) with 3-(3)H-glucose; determination of fat mass ((3)H(2)O); and measurement of fasting glucose, free fatty acids (FFAs), leptin, adiponectin, and TNFalpha concentrations. After 4 months of PIO, fasting plasma glucose concentration (Delta = -2.7 mol/liter), mean plasma glucose during OGTT (Delta = -3.8 mol/liter), and hemoglobin A(1c) (Delta = 1.7%) decreased (P < 0.05 vs. placebo) without change in fasting or post-OGTT plasma insulin levels. Fasting FFAs (Delta = 168 micromol/liter) and TNFalpha (Delta = 0.7 pg/ml) concentrations decreased (P < 0.05 vs. placebo), whereas adiponectin (Delta = 8.7 microg/ml) increased (P < 0.01 vs. placebo). Despite the increase in body fat mass (Delta = 3.4 kg) after PIO, plasma leptin concentration did not change significantly. No changes in plasma glucose, FFAs, or adipocytokine levels were observed in placebo-treated subjects. During the insulin clamp, endogenous (hepatic) glucose production decreased (Delta = -2.67 micromol/fat-free mass.min, P < 0.05 vs. placebo), whereas metabolic clearance rate of glucose (MCR) increased (Delta = 0.58 ml/fat-free mass.min, P < 0.05 vs. placebo) after PIO. In all subjects, before and after PIO, the decrease in plasma FFA concentration was correlated with the changes in both endogenous (hepatic) glucose production (r = 0.47, P < 0.05) and MCR (r = -0.41, P < 0.05), whereas the increase in plasma adiponectin concentration was correlated with the change in endogenous (hepatic) glucose production (r = -0.70, P < 0.01) and MCR (r = 0.49, P < 0.05). These results suggest that the direct effects of PIO on adipose tissue to decrease plasma FFA levels and increase plasma adiponectin contribute to the improvements in hepatic and peripheral insulin sensitivity and glucose tolerance in patients with T2DM.

Adiponectin↗

Association of adiponectin level and variants in the adiponectin gene with glucose metabolism, energy expenditure, and cytokines in offspring of type 2 diabetic patients.

OBJECTIVE: Adiponectin is an adipose-specific secretory protein abundantly present in the circulation. The role of adiponectin in the control of energy expenditure and substrate utilization has not yet been established. DESIGN: We performed detailed metabolic studies in a large cohort (n = 158) of offspring of patients with type 2 diabetes (T2DM) to determine the association of adiponectin level with glucose and lipid oxidation, energy expenditure, insulin sensitivity, and visceral obesity by applying the euglycemic clamp technique and indirect calorimetry. RESULTS: The adiponectin level was lower in offspring of T2DM patients than in control subjects. When the data were analyzed by adiponectin tertiles, an elevated adiponectin level was associated with high total, oxidative, and nonoxidative glucose disposal and high energy expenditure during hyperinsulinemia; low levels of free fatty acids and low rates of lipid oxidation during hyperinsulinemia; as well as low levels of inflammatory cytokines; and a low amount of intraabdominal fat evaluated by computed tomography. No association of single nucleotide polymorphism 45 or single nucleotide polymorphism 276 with adiponectin level was found. CONCLUSIONS: We conclude that adiponectin has multiple effects on glucose, lipid and free fatty acid metabolism, and cytokines in offspring of T2DM subjects.

Adiponectin↗

Plasma adiponectin level is associated with insulin-stimulated nonoxidative glucose disposal.

CONTEXT: Impaired nonoxidative glucose disposal and decrease in mitochondrial glucose oxidation both contribute to insulin resistance in diabetic subjects. OBJECTIVE: In the present study, we investigated whether plasma adiponectin is associated with glucose oxidation and nonoxidative glucose disposal in subjects with and without type 2 diabetes. DESIGN: Euglycemic-hyperinsulinemic clamp was performed in 42 type 2 diabetic (T2DM) and 13 nondiabetic (non-DM) subjects. The whole-body glucose disposal rate (GDR) was evaluated as the mean of the glucose infusion rate during steady state of the clamp. Glucose and fat oxidation rates were assessed by indirect calorimetry, and nonoxidative glucose disposal rate was calculated by subtracting glucose oxidation rate from GDR. RESULTS: Plasma adiponectin level was significantly lower in T2DM than non-DM (2.87 +/- 1.40 vs. 3.96 +/- 2.39 microg/ml, P = 0.045). GDR (3.39 +/- 1.53 vs. 4.83 +/- 1.70 mg/kg x min, P = 0.006) and nonoxidative glucose disposal rate (1.89 +/- 1.39 vs. 3.11 +/- 1.76 mg/kg x min, P = 0.012) were significantly lower in T2DM, compared with non-DM, although no difference was found in glucose oxidation rate between the two groups. In all subjects, plasma adiponectin level was positively correlated with GDR (r = 0.351, P = 0.009) and nonoxidative glucose disposal rate (r = 0.324, P = 0.016) but not glucose oxidation rate. There was no significant correlation between plasma adiponectin level and fat oxidation, either before or during the clamp. CONCLUSIONS: In conclusion, plasma adiponectin level is associated with nonoxidative glucose disposal, which is reduced in type 2 diabetic subjects. Our results suggest that adiponectin controls insulin sensitivity by modulating the glycogen synthetic process in human skeletal muscle.

Adiponectin↗

Effects of short-term experimental insulin resistance and family history of diabetes on pancreatic beta-cell function in nondiabetic individuals.

CONTEXT: Normal glucose homeostasis is maintained despite reductions in insulin sensitivity by increasing insulin secretion. This ability to compensate for reduced insulin sensitivity is highly heritable, but the mechanisms for this compensation or its failure in type 2 diabetes (T2DM) are unknown. OBJECTIVE: The objective of this study was to test whether individuals with a family history of T2DM have a fixed decrease in beta-cell mass or function that would be revealed as an impaired insulin secretory response to short-term insulin resistance. DESIGN: Glucose tolerance, insulin sensitivity (S(I)), and insulin response to i.v. glucose (AIR(G)) were compared in nondiabetic individuals with and without a family history of diabetes before and after nicotinic acid (NA) treatment. SETTING: This study was performed at the Ambulatory General Clinical Research Center. SUBJECTS: Healthy, nonobese, nondiabetic individuals with or without a family history of T2DM were studied. INTERVENTIONS: Oral NA was given, with a final dose of 2 g/d, for at least 7 d. MAIN OUTCOME MEASURE: The main outcome measure was the disposition index (insulin sensitivity x insulin response) in response to NA. RESULTS: Postchallenge plasma glucose levels rose during NA therapy regardless of family history. Neither group adequately increased their AIR(G) to maintain the disposition index. Family members did not differ from controls at baseline or after NA treatment for any outcome measure, but only 28 of 52 subjects experienced a 25% or greater fall in S(I) with NA treatment. CONCLUSIONS: Short-term beta-cell compensation to NA-induced insulin resistance was incomplete and did not differ by genetic predisposition. A genetic defect controlling beta-cell growth in response to chronic insulin resistance better explains differences in the ability to compensate for insulin resistance than an inherited, fixed defect in beta-cell mass.

Adolescent↗

Activation of peroxisome proliferator-activated receptor-gamma by rosiglitazone protects human islet cells against human islet amyloid polypeptide toxicity by a phosphatidylinositol 3'-kinase-dependent pathway.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is characterized by a deficit in beta-cell mass, increased beta-cell apoptosis, and islet amyloid derived from islet amyloid polypeptide (IAPP). Human IAPP (h-IAPP) applied to beta-cells forms toxic oligomers that induce apoptosis. Thiazolidinediones, ligands of peroxisome proliferator-activated receptor-gamma (PPAR-gamma), can delay the onset of T2DM. OBJECTIVE: We questioned whether activation of endogenous PPAR-gamma in human islets by rosiglitazone (RSG) inhibits h-IAPP-induced islet cell death and, if so, by which mechanism. METHODS AND RESULTS: Vehicle or h-IAPP was applied to human islets with or without RSG (10 and 50 microM) for 48 h. A 2-fold increase in the number of terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick end labeling-positive nuclei was detected in h-IAPP-treated human islets (P < 0.001). RSG (10 and 50 microM) prevented h-IAPP-induced apoptosis in human islets (P < 0.001). Thioflavin T binding assays confirmed that this effect was not mediated by interference with h-IAPP oligomerization. Expression of dominant negative PPAR-gamma in human islets prevented the protective effect of RSG. RSG activation of PPAR-gamma resulted in downstream activation of the serine/threonine protein kinase Akt, an outcome that was inhibited by a specific phosphatidylinositol 3-kinase inhibitor, which ablated RSG protection against h-IAPP-induced islet cell apoptosis. CONCLUSION: We conclude that in human islets, activation of PPAR-gamma inhibits h-IAPP-induced islet cell apoptosis, and this action is at least in part mediated through activation of the phosphatidylinositol 3'-kinase-Akt cascade. If this action is present in vivo, then thiazolidinediones have the potential to decrease beta-cell apoptosis in T2DM and reduce loss of beta-cell mass.

Amyloid↗

Serum gamma-glutamyl transpeptidase is a determinant of insulin resistance independently of adiposity in Pima Indian children.

CONTEXT: Elevated activities of serum enzymes, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyltransferase (GGT), have been associated with obesity and insulin resistance (IR). ALT is an independent predictor of type 2 diabetes mellitus (T2DM) in adult Pima Indians, and GGT predicts T2DM in other adult populations. OBJECTIVE: Our aim was to establish whether independent relationships exist between either adiposity or IR and hepatic enzymes in a group of Pima Indian children. SUBJECTS AND METHODS: In a cross-sectional study, 44 children (22 males and 22 females; 7-11 yr old) were measured for weight (WT), height, percent body fat, and serum activities of ALT, AST, and GGT. Body mass index (kilograms per meter squared) was calculated. IR was calculated from fasting plasma concentrations of glucose and insulin using the homeostasis model assessment (HOMA-IR). RESULTS: Hepatic enzymes were positively associated with obesity measures, fasting insulin, and HOMA-IR. GGT was additionally associated with serum lipids and white blood cell count. GGT, but not AST or ALT, was a significant determinant of HOMA-IR independently of age, sex, and WT, body mass index, or percent body fat. The model that accounted for the largest portion of the variance in HOMA-IR included WT (beta = 0.004; P = 0.008) and GGT (beta = 0.20; P = 0.004; total R(2) = 0.62; P < 0.0001). CONCLUSION: Significant relationships between adiposity and hepatic enzyme activities exist during childhood in Pima Indians. Whether serum GGT activity predicts the development of T2DM in these children remains to be determined in follow-up studies.

Adipose Tissue↗

A common mitochondrial DNA variant and increased body mass index as associated factors for development of type 2 diabetes: Additive effects of genetic and environmental factors.

OBJECTIVE: The suggested correlation between a T-to-C transition at the nucleotide 16189 in mitochondrial DNA (mtDNA) with increasing insulin resistance and adult-onset diabetes mellitus (DM) is debatable. METHODS: Our study examined mtDNA from 462 subjects with type 2 diabetes (T2DM) and 592 normoglycemic controls (non-DM). Each participant's body mass index (BMI), fasting plasma glucose, fasting insulin concentration, insulin resistance index, and beta-cell function were measured. Sequencing for mtDNA, focusing on exploration of the hypervariable polycytosine tract within the control region, was also conducted in all subjects. RESULTS: Prevalence of the mtDNA 16189 variant was significantly different between DM and non-DM subjects (39.2% vs. 30.7% respectively; P = 0.004). Increased incidence of DM was noted in those harboring the 16189 variant compared with those lacking the variant (multivariate odds ratio, 1.38; 95% confidence interval, 1.07-1.80). Moreover, increased BMI was identified as an aggravating factor for development of DM in subjects harboring the variant. Odds ratio determinations yielded 2.14 in overweight and 4.63 in obese subjects harboring the variant in comparison with subjects without (1.83 in overweight and 2.16 in obese subjects). This is consistent with a progressively increased prevalence of the mtDNA 16189 variant in the non-DM groups with higher fasting insulin concentration, insulin resistance index, and beta-cell function (all P(trend) < 0.005). CONCLUSION: The mtDNA 16189 variant can influence development of T2DM. The demonstrated dynamic between the 16189 variant and increased BMI exemplify an additive effect of genetic and environmental factors on the pathogenesis of T2DM.

Adult↗

The in vitro effects of resistin on the innate immune signaling pathway in isolated human subcutaneous adipocytes.

CONTEXT: Obesity-associated inflammation is a contributory factor in the pathogenesis of type 2 diabetes mellitus (T2DM); the mechanisms underlying the progression to T2DM are unclear. The adipokine resistin has demonstrated proinflammatory properties in relation to obesity and T2DM. OBJECTIVES: The objectives of this study were to characterize resistin expression in human obesity and address the role of resistin in the innate immune pathway; to examine the influence of lipopolysaccharide, recombinant human resistin (rhResistin), insulin, and rosiglitazone in human adipocytes; and, finally, to analyze the effect of rhResistin on the expression of components of the nuclear factor-kappaB pathway and insulin signaling cascade. METHODS: Abdominal sc adipose tissue was obtained from patients undergoing elective liposuction surgery (n = 35; age, 36-49 yr; body mass index, 26.5 +/- 5.9 kg/m2). Isolated adipocytes were cultured with rhResistin (10-50 ng/ml). The level of cytokine secretion from isolated adipocytes was examined by ELISA. The effect of rhResistin on protein expression of components of the innate immune pathway was examined by Western blot. RESULTS: In vitro studies demonstrated that antigenic stimuli increase resistin secretion (P < 0.001) from isolated adipocytes. Proinflammatory cytokine levels were increased in response to rhResistin (P < 0.001); this was attenuated by rosiglitazone (P < 0.01). When examining components of the innate immune pathway, rhResistin stimulated Toll-like receptor-2 protein expression. Similarly, mediators of the insulin signaling pathway, phosphospecific c-Jun NH2-terminal kinase (JNK) 1 and JNK2, were up-regulated in response to rhResistin. CONCLUSION: Resistin may participate in more than one mechanism to influence proinflammatory cytokine release from human adipocytes, potentially via the integration of nuclear factor-kappaB and JNK signaling pathways.

Adipocytes↗

Vanadyl sulfate improves hepatic and muscle insulin sensitivity in type 2 diabetes.

Vanadyl sulfate (VOSO(4)) is an oxidative form of vanadium that in vitro and in animal models of diabetes has been shown to reduce hyperglycemia and insulin resistance. Small clinical studies of 2- to 4-week duration in type 2 diabetes (T2DM) have led to inconsistent results. To define its efficacy and mechanism of action, 11 type 2 diabetic patients were treated with VOSO(4) at a higher dose (150 mg/day) and for a longer period of time (6 weeks) than in previous studies. Before and after treatment we measured insulin secretion during an oral glucose tolerance test, and endogenous glucose production (EGP) and whole body insulin-mediated glucose disposal using the euglycemic insulin clamp technique combined [3-(3)H]glucose infusion. Treatment significantly improved glycemic control: fasting plasma glucose (FPG) decreased from 194 +/- 16 to 155 +/- 15 mg/dL, hemoglobin A(1c) decreased from 8.1 +/- 0.4 to 7.6 +/- 0.4%, and fructosamine decreased from 348 +/- 26 to 293 +/- 12 micromol/L (all P < 0.01) without any change in body weight. Diabetics had an increased rate of EGP compared with nondiabetic controls (4.1 +/- 0.2 vs. 2.7 +/- 0.2 mg/kg lean body mass.min; P< 0.001), which was closely correlated with FPG (r = 0.56; P< 0.006). Vanadyl sulfate reduced EGP by about 20% (P< 0.01), and the decline in EGP was correlated with the reduction in FPG (r = 0.60; P< 0.05). Vanadyl sulfate also caused a modest increase in insulin-mediated glucose disposal (from 4.3 +/- 0.4 to 5.1 +/- 0.6 mg/kg lean body mass x min; P< 0.03), although the improvement in insulin sensitivity did not correlate with the decline in FPG after treatment (r = -0.16; P = NS). Vanadyl sulfate treatment lowered the plasma total cholesterol (223 +/- 14 vs. 202 +/- 16 mg/dL; P < 0.01) and low density lipoprotein cholesterol (141 +/- 14 vs. 129 +/- 14 mg/dL; P < 0.05), whereas 24-h ambulatory blood pressure was unaltered. We conclude that VOSO(4) at maximal tolerated doses for 6 weeks improves hepatic and muscle insulin sensitivity in T2DM. The glucose-lowering effect of VOSO(4) correlated well with the reduction in EGP, but not with insulin-mediated glucose disposal, suggesting that liver, rather than muscle, is the primary target of VOSO(4) action at therapeutic doses in T2DM.

Blood Pressure↗

Short-term changes in insulin resistance following weight loss surgery for morbid obesity: laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: Laparoscopic adjustable gastric banding (LAGB) and laparoscopic Roux-en-Y gastric bypass (LRYGBP) both effectively treat the insulin resistance associated with type 2 diabetes mellitus (T2DM). Restriction of caloric consumption, alterations in the entero-insular axis or weight loss may contribute to lowering insulin resistance after these procedures. The relative importance of these mechanisms, however, following LAGB and LRYGBP remain unclear. The aim of this study was to compare directly the short-term changes in insulin resistance following LAGB and LRYGBP in similar populations of patients. METHODS: Patient preference determined operation type. The Homeostasis Model Assessment for Insulin Resistance (HOMA IR) was used to measure insulin resistance. Preoperative values were compared to postoperative levels obtained within 90 days of surgery. Significant differences between groups were tested by ANOVA. RESULTS: There were no significant preoperative differences between groups. The 56 LAGB patients had a mean age of 42.5 years (25.7-63), BMI of 45.5 kg/m(2) (35-66) and preoperative HOMA IR of 4.1 (1.4-39.2). 75% of LAGB patients were female and 43% had T2DM. The 61 LRYGBP patients had a median age of 39.9 years (22.1-64.3), BMI of 45.0 kg/m(2) (36-62), and preoperative HOMA IR of 5.0 (0.6-56.5). 79% of LRYGBP patients were women and 44.3% had T2DM. Median follow-up for LAGB patients was 45 days (18-90) and for LRYGBP patients 46 days (8-88 days). LAGB patients had a median of 14.8% excess weight loss (6.9%-37.0%) and LRYGB patients 24.2% (9.8%-51.4%). Postoperative HOMA IR was significantly less after LRYGBP, 2.2 (0.7-12.2), than LAGB, 2.6 (0.8-29.6), although change in HOMA IR was not significantly different. Change in HOMA IR for both groups did not vary with length of follow-up or weight loss but correlated best with preoperative HOMA IR (LAGB r=0.8264; LRYGBP r=0.9711). CONCLUSIONS: Both LAGB and LRYGBP significantly improved insulin resistance during the first 3 months following surgery. Both operations generated similar changes in HOMA IR, although postoperative HOMA IR levels were significantly lower after LRYGBP. These findings suggest that caloric restriction plays a significant role in improving insulin resistance after both LAGB and LRYGBP.

Adult↗

Safety and efficacy of low-dose pioglitazone (7.5 mg/day) vs. standard-dose pioglitazone (15 mg/day) in Japanese women with type 2 diabetes mellitus.

It is well known that pioglitazone, a potent thiazolidinedione, improves metabolic control. However, weight gain or peripheral edema may be of major clinical concern when using this agent. The purpose of our study was to prospectively evaluate the effects of low-dose pioglitazone (7.5 mg/day) on metabolic control, weight gain and the incidence of edema compared with a standard dose of pioglitazone (15.0 mg/day) in patients with type 2 diabetes mellitus (T2DM). Ninety-five Japanese female patients (mean age 58.4 +/- 10.4 years) with newly diagnosed T2DM were selected for this study. They were randomly divided into the following 2 groups according to therapy regimens, and examined every month for 6 months after diagnosis. Group A consisted of 54 patients treated with low-dose pioglitazone orally; Group B, the control-group, consisted of 41 patients treated with standard-dose pioglitazone orally. The incidence of peripheral edema was significantly much lower in group A (2/54) than in group B (11/41) (p = 0.0014). In addition, % change of body weight during the 6-month treatment in group A was significantly less than that in group B (p < 0.0001). On the other hand, the % change of biochemical parameters including HbA1c did not differ significantly between group A and group B, although glucose and lipid control significantly improved from baseline in both groups. Our results demonstrate the safety and efficacy of low-dose pioglitazone, suggesting that it could be another good choice of treatment for Japanese women with T2DM.

Administration, Oral↗

Selective PPAR modulators, dual and pan PPAR agonists: multimodal drugs for the treatment of type 2 diabetes and atherosclerosis.

More than 70% of patients with Type 2 diabetes mellitus (T2DM) die because of cardiovascular diseases. Current therapeutic strategies are based on separate treatment of insulin resistance and dyslipidaemia. Development of drugs with multimodal activities should improve management of the global cardiovascular risk of T2DM patients and result in better patient compliance. New therapeutic strategies are aimed at targeting the entire spectrum of dysfunctioning organs, cells and regulatory pathways implicated in the pathogenesis of T2DM, dyslipidaemia and atherosclerosis. PPAR family members play major roles in the regulation of lipid metabolism, glucose homeostasis and inflammatory processes, making these transcription factors ideal targets for therapeutic strategies against these diseases. This review discusses why PPARs and development of novel selective PPAR modulators, dual and pan PPAR agonists constitute promising approaches for the treatment of diabetes, dyslipidaemia and atherosclerosis.

Animals↗

Body weight and glucose metabolism have a different effect on circulating levels of ICAM-1, E-selectin, and endothelin-1 in humans.

BACKGROUND: Endothelial dysfunction and inflammation are present in both type 2 diabetes mellitus (T2DM) and obesity. In this paper we compared the role of weight loss and of glycaemic control in determining circulating levels of ICAM-1, endothelin-1 (ET-1), and E-selectin in patients with morbid (grade 3) obesity. METHODS AND RESULTS: ICAM-1, E-selectin, and ET-1 were higher in obese patients (n=96) than in lean controls (n=30); among obese patients, the three molecules were higher in T2DM patients (n=26) than in patients with normal (NGT, n=43) or impaired (IGT, n=27) glucose tolerance. Sixty-eight obese patients had a significant weight loss induced by bariatric surgery, and showed a significant decrease in blood glucose, HbA1c and all molecules, so that ICAM-1, E-selectin, and ET-1 were not different in NGT, IGT and T2DM patients, and in lean controls; in 13 patients with a small weight loss induced by diet, changes were not significant, in spite of a significant reduction in blood glucose and HbA1c. At stepwise regression, changes in ICAM-1, ET-1, and E-selectin significantly correlated only with change in body mass index. CONCLUSIONS: These data indicate that weight loss is more important than glycaemic control in regulating circulating levels of ICAM-1, ET-1, E-selectin in morbidly obese subjects.

Adult↗