Increased urinary albumin excretion is associated with a cluster of metabolic alterations in type 2 diabetes mellitus

The relationship between urinary albumin excretion rate (UAE) and some metabolic and haemodynamic characteristics was studied in 62 (50 male, 12 female) type 2 (non-insulin-dependent) diabetic patients, with (26 male, 5 female) and without (24 male, 7 female) ischaemic heart disease (IHD), free from overt diabetic nephropathy. The overall population was subdivided into quartiles on the basis of UAE values (mg/24h): group 1 (16 subjects), 3.3–7 (range); group 2 (15 subjects), 7.22–11.8; group 3 (15 subjects), 11.9–30; group 4 (16 microalbuminuric subjects), 31.7–226. The groups were comparable with regard to age, duration of diabetes and prevalence of smokers. From group 1 to group 4 we found increasing levels of body mass index (BMI) (24.2±0.6, 26.6±0.7, 27.6±0.7, 27.6±0.9 kg/m²;P=0.007), HbA_1c (5.99±0.2, 6.45±0.35, 7.02±0.41, 7.4±0.39%;P=0.017), total cholesterol (5.30±0.26, 5.51±0.34, 6.14±0.21, 6.32±0.26 mmol/l;P=0.026), triglycerides (1.37±0.20, 1.67±0.21, 2.07±0.29, 2.55±0.45 mmol/l;P=0.034) and prevalence of hypertension (50%, 67%, 67%, 81%;P=0.088). No significant differences were found between C-peptide, insulin resistance (K index of insulin tolerance test) and high-density lipoprotein (HDL)-cholesterol levels. Groups 1+2 had a lower prevalence of IHD in comparison with groups 3+4 (42% vs 58%,P=0.069). Using multiple regression analysis, only HbA_1c was independently associated with log₁₀ UAE in the overall population (P=0.002), including as independent variables age, duration of diabetes, BMI, total cholesterol, triglycerides and mean arterial pressure. In conclusion: (1) type 2 diabetic patients show higher BMI, HbA_1c, total cholesterol, triglyceride levels and prevalence of hypertension with increasing UAE, even in the normoalbuminuric range; (2) the prevalence of IHD is higher in the groups with elevated UAE; (3) glycaemic control is the only metabolic characteristic independently associated with UAE.     

Upregulation of SCUBE2 expression in dyslipidemic type 2 diabetes mellitus is associated with endothelin-1

Type 2 diabetes mellitus (T2DM) is a major health problem for morbidity and mortality world-wide due to diabetic vascular complication. Following T2DM, dyslipidemia is known well for the main reason of vascular complication leading to atherosclerosis and impaired life expectancy in diabetes. Thus, a new prediction marker in T2DM could help prevent the progression disease despite of metabolic control. Signal peptide–CUB-EGF like containing protein 2 (SCUBE2), has been detected in vascular endothelium and was affected by cytokines. Recently, SCUBE2 was reported to increase in atherosclerotic human coronary artery, involving vascular smooth muscle cells (VSMCs) and macrophages. The aims of this study were to examine the expression level of SCUBE2 in T2DM patients with dyslipidemia and its correlation with endothelial dysfunction marker, endothelin-1 (ET-1) in this group. This study design was cross sectional control study, recruited 28 patients diagnosed as T2DM who were found with dyslipidemia and 15 healthy control subjects. Our results showed that T2DM patients showed higher LDL cholesterol, triglycerides, and ET-1 expression level compared to healthy subjects. Further, we found that SCUBE2 had strong correlation with ET-1 in these dyslipidemic T2DM patients. In conclusion, our study confirmed first that SCUBE2 was upregulated in T2DM with dyslipidemia. Moreover, Pearson correlation analysis of ET-1 and SCUBE2 in this group showed high correlation r = 0.797, P < 0.001, suggesting that SCUBE2 may plausible target in vascular function changes in dyslipidemic T2DM. Improving our exploration of these findings may lead to uncover SCUBE2 involvement in diabetic vascular complication in T2DM.     

Receptor phosphorylation mediates estradiol reduction of alpha2-adrenoceptor coupling to G protein in the hypothalamus of female rats

Estrogen increases evoked norepinephrine release in the hypothalamus of female rodents, in part by reducing the ability of α₂-adrenoceptors to act as negative feedback inhibitors of norepinephrine release. Estrogen enhancement of norepinephrine release in the hypothalamus correlates with decreased coupling of the α₂-adrenoceptor to G protein. To determine the mechanism by which estrogen uncouples α₂-adrenoceptors from G protein, we tested the hypothesis that estrogen increases α₂-adrenoceptor phosphorylation. Short-term activation of endogenous serine/threonine phosphatases with protamine or treatment with exogenous phosphatase restored α₂-adrenoceptor coupling to G protein to control levels in hypothalami from estrogen-exposed female rats. Additional experiments examined whether estrogen alters G protein-coupled receptor kinase expression or activity or serine/threonine phosphatase activity. These proteins are involved in G protein-coupled receptor phosphorylation, internalization, and recycling. Estrogen exposure reduced G protein-coupled receptor kinase mRNA, protein, and activity in the hypothalamus. Furthermore, estrogen treatment reduced serine/threonine phosphatase activity in the hypothalamus. Analysis of ligand binding in subcellular fraction demonstrated that estrogen decreases the fraction of internalized α₂-adrenoceptors in the hypothalamus. Therefore, estrogen promotes norepinephrine release in the hypothalamus by stabilizing α₂-adrenoceptor phosphorylation, uncoupling the receptor from G protein. Estrogen may stabilize α₂-adrenoceptor phosphorylation by inhibiting receptor internalization and dephosphorylation.     

Increased cholesterylester transfer activity in complicated Type 1 (insulin-dependent) diabetes mellitus — its relationship with serum lipids

Summary In Type 1 (insulin-dependent) diabetes mellitus, macrovascular complications and the increased risk for cardiovascular disease in patients with microvascular complications may be related to alterations in plasma cholesterylester transfer. The activity of cholesterylester transfer protein, which mediates cholesterylester transfer between lipoproteins and lipoprotein lipid levels, was assessed in 7 normolipidaemic control subjects, 7 Type 1 diabetic control subjects without complications, 11 Type 1 diabetic patients with microvascular complications (retinopathy, incipient nephropathy) and in 7 Type 1 diabetic patients with macrovascular atherosclerotic lesions.The cholesterylester transfer activity was 30% higher in the diabetic groups with macrovascular and microvascular lesions than in the 2 control groups. Very low + low density lipoprotein cholesterol was higher in the 3 diabetic groups than in the non-diabetic control group. High density lipoprotein cholesterol was not different. The cholesterylester transfer activity was correlated positively with HbA1, urinary albumin excretion rate, serum cholesterol, very low + low density lipoprotein cholesterol and apolipoprotein B. The high density lipoprotein over very low + low density lipoprotein cholesterylester molar ratio was lower in the diabetic groups with micro- and macrovascular complications. A role for cholesterylester transfer activity in the lipoprotein abnormalities found in complicated Type 1 diabetes is suggested. A high cholesterylester transfer activity might be indicative of mechanisms which promote atherogenesis.     

Vitamin D receptor levels and binding are reduced in aged rat intestinal subcellular fractions

The hormonal form of vitamin D, 1α,25(OH)₂-vitaminD₃ [1α,25(OH)₂D₃], stimulates signal transduction pathways in intestinal cells. To gain insight into the relative importance of the vitamin D receptor (VDR) in the rapid hormone responses, the amounts and localization of the VDR were evaluated in young (3 months) and aged (24 months) rat intestinal cells. Immune-fluorescence and Western blot studies showed that VDR levels are diminished in aged enterocytes. Confocal microscopy assays revealed that the VDR and other immune-reactive proteins have mitochondrial, membrane, cytosol and perinuclear localization. Western blot analysis using specific antibodies detected the 60 and 50 kDa bands expected for the VDR in the cytosol and microsomes and, to a lesser extent, in the nucleus and mitochondria. Low molecular weight immune-reactive proteins were also detected in young enterocytes subcellular fractions. Since changes in hormone receptor levels appear to constitute a common manifestation of the ageing process, we also analyzed 1α,25(OH)₂D₃ binding properties and VDR levels in subcellular fractions from young and aged rats. In competition binding assays, employing [³H]-1α,25(OH)₂D₃ and 1α,25(OH)₂D₃, we have detected specific binding in all subcellular fractions, with maximum binding in mitochondrial and nuclear fractions. Both, VDR protein levels and 1α,25(OH)₂D₃ binding, were diminished with ageing. Age-related declines in VDR may have important consequences for correct receptor/effector coupling in the duodenal tissues and may explain age-related declines in the hormonal regulation of signal transduction pathways that we previously reported.     

A genetic marker at the glucokinase gene locus for Type 2 (non-insulin-dependent) diabetes mellitus in Mauritian Creoles

Summary The prevalence of Type 2 (non-insulin-dependent) diabetes mellitus is high in Mauritius, a multiethnic island nation in the southwestern Indian Ocean. Evaluation of candidate genes in the different ethnic groups represents a means of assessing the genetic component. As glucokinase is known to be a key regulator of glucose homeostasis in liver and pancreatic Beta-cells, the human gene was isolated and a dinucleotide repeat (CA)_n marker was identified at this locus. A polymerase chain reaction assay was developed, and alleles differing in size were observed in individuals, according to the number of repeats in the amplified fragment. Eighty-five Creoles and 63 Indians of known glucose tolerance status were typed by amplification of genomic DNA for this dinucleotide (CA)_n repeat marker. Four different alleles were observed including Z, the most common allele, and Z+2, Z+4, and Z+10, which differed from Z by 2, 4, and 10 nucleotides respectively. In Mauritian Creoles, the frequency of the Z+2 allele was greater in Type 2 diabetic subjects than in control subjects (23.8 % vs 8.9 %, p=0.008), and the frequency of the Z allele was lower in Type 2 diabetic subjects (60% vs 75.6%, p=0.03). Analysis with univariate logistic regression models indicated that the Z+2 allele had the highest odds ratio, 3.08 (95% confidence interval 1.14–8.35, p=0.0416), among the other risk factors (age, sex, body mass index, and waist/hip ratio). The multivariate odds ratio for Type 2 diabetes was 2.88 (95% confidence interval 0.98–8.50, p=0.0551). In contrast, in the Mauritian Indian population, no differences were noted between the frequency of any glucokinase allele in the Type 2 diabetic and control groups. These data suggest that the Z+2 allele is an important risk factor for Type 2 diabetes in Mauritian Creoles, but not in Mauritian Indians, and also imply that the glucokinase gene may play a role in the pathogenesis of Type 2 diabetes in Mauritian Creoles. Further studies are needed to define the nature of this defect.     

Assessment of energy expenditure using doubly labeled water,physical activity by accelerometer and reported dietary intake in Japanese men with type 2 diabetes: A preliminary study

The aim of the present study was to determine the total energy expenditure, physical activity and dietary intake of men with type 2 diabetes mellitus and control participants without type 2 diabetes mellitus who were matched for age and body mass index. The participants in the present study were 12 well‐controlled type 2 diabetes mellitus patients and 10 controls, aged 40–75 years, with a body mass index <30 kg/m². Total energy expenditure under free‐living conditions was assessed using the doubly labeled water method, and physical activity was measured using a triaxial accelerometer. Dietary intake was assessed using a self‐recorded food intake diary during the measurement period. Participants were instructed to record their dietary intake over 3 days, including 2 weekdays. Total energy expenditure was not significantly different between the groups (P = 0.153), nor were energy (P = 0.969) or macronutrient intakes. In conclusion, when age and body mass index are matched, total energy expenditure and self‐reported energy intake are not significantly different between type 2 diabetes mellitus patients and healthy controls.     

Stathmin levels in growth plate chondrocytes are modulated by vitamin D3 metabolites and transforming growth factor-beta1 and are associated with proliferation

Stathmin is a highly conserved, phosphorylated cytosolic protein that is found at decreased levels in all cells as they become more terminally differentiated, or when they decrease in their rate of proliferation. This study examined the hypothesis that stathmin levels in growth plate chondrocytes decreases as endochondral maturation increases. To test this hypothesis, we used a costochondral growth plate chondrocyte cell culture model. Cells derived from the resting zone (RC) express twice as much stathmin mRNA in culture and have twice as much stathmin protein as cells derived from the post proliferative growth zone ([GC];prehypertrophic and upper hypertrophic cell zones). Stathmin levels in vivo were assessed by immunohistochemistry. To assess the effects of agents that modulate proliferation and differentiation, RC and GC chondrocytes were cultured in the presence of 10⁻¹⁰ to 10⁻⁸ M 1α,25-(OH)₂D₃, which regulates proliferation in both cell types but affects differentiation of only GC cells, or 10⁻⁹ to 10⁻⁷ M 24R,25-(OH)₂D₃, which regulates differentiation and maturation of RC cells, but decreases proliferation of GC cells. In addition, RC cells were treated with 0.44 or 0.88 ng/mL of recombinant human transforming growth factor β1 (rhTGF-β1), which stimulates proliferation of RC cells and regulates proteoglycan production, but not alkaline phosphatase activity. Stathmin protein levels were determined using quantitative immunoblots, with recombinant human stathmin as a standard. The results show that stathmin levels are associated with proliferation. Proliferating chondrocytes in vivo exhibited higher levels of immunoreactive stathmin than either RC or GC cells in the growth plate. In culture, 1α,25-(OH)₂D₃ caused a dose-dependent de-crease in stathmin in RC and GC cells within 24 h. 24 R, 25-(OH)₂D₃ also reduced stathmin levels in GC cells within 24 h but only affected RC cells after prolonged exposures (96 h), at which time RC cells express a GC-like phenotype. rhTGF-β1 caused an increase in stathmin levels in RC cells. Stathmin levels are sensitive to protein kinase C (PKC) in other cells. Inhibition of PKC with chelerythrine had no effect on the response of RC cells to 1α,25-(OH)₂D₃ but it blocked the effect of rhTGF-β1, indicating that decreases in stathmin by vitamin D₃ metabolites may not be modulated by PKC, whereas increases in stathmin via rhTGF-β1 may be regulated via a PKC-dependent mechanism. These results support the hypothesis that constitutively expressed levels of stathmin are related to cell maturation state and that they are modulated by factors that regulate proliferation.     

Increased mean carotid intima media thickness in type 2 diabetes mellitus patients with non-blood pressure component metabolic syndrome: A preliminary report

AIMS:

Patients with type-2 diabetes mellitus have greater carotid intima media thickness and they are at risk for generalized atherosclerosis. This study aimed to compare the thickness of carotid artery intima media in type-2 diabetes mellitus patients with and without nonblood pressure component metabolic syndrome.

SETTINGS AND DESIGN:

This was a comparative observational study conducted in the Departments of Pharmacology and Physiology in the College of Medicine, Al-Mustansiriyia University in cooperation with Baghdad Teaching Hospital.

MATERIALS AND METHODS:

Forty-six diabetic patients of both sexes with systolic blood pressure < 130 mm Hg and diastolic blood pressure < 85 mm Hg were subjected to high resolution B-mode ultrasonography of the common and internal carotid arteries. Patients were grouped into those without metabolic syndrome (Group I) and with nonblood pressure component metabolic syndrome (Group II).

STATISTICAL ANALYSIS:

The two-tailed unpaired Student''s t-test was used in this study.

RESULTS:

Significantly high mean thickness was observed in the common carotid intima media (0.824 ± 0.155 mm) but not in the internal carotid arteries in group II patients compared to group I patients (0.708 ± 0.113 mm). Group II also had a significant number of patients with increased lesion intima media thickness (≥ 1.1 mm).

Conclusion:

The greater carotid intima media thickness observed in type 2 diabetes mellitus patients is related to the metabolic syndrome even in the absence of the blood pressure component.     

Autoantibodies against adrenal medulla in type 1 and type 2 diabetes mellitus: no evidence for an association with autonomic neuropathy

Objective. To examine the role of autoimmunity in the development of autonomic neuropathy in diabetes mellitus.
Design. Retrospective cross-sectional study.
Setting. The Department of Medicine, University Hospital, Uppsala, and the Department of Endocrinology, University of Lund, Malmö General Hospital, Malmö, Sweden.
Subjects and main outcome measures. We examined 135 patients with type 1 ( n =96) or type 2 ( n =39) diabetes mellitus. Tests for cardiovascular autonomic functions were performed, and patient sera were analysed for the presence of autoantibodies against the adrenal medulla by indirect immunofluorescence, Western blot and immunoprecipitation techniques.
Results. Sera from 13% (12/96) of the type 1 and 20% (8/39) of the type 2 patients showed a positive cytoplasmic immunofluorescence (IF) staining of the adrenal medullary cells, as did 20% (30/151) of sera from healthy controls. Fifty-eight and 64% of type 1 and type 2 patients, respectively, had cardiovascular autonomic neuropathy, but no correlation between autonomic neuropathy and positive IF against the adrenal medulla was observed, with the exception of significant drops in diastolic blood pressure 8 min after tilt ( P <0.005) in type 1 patients. The various IF-positive sera reacted with several different proteins when analysed with Western blot technique using a total homogenate of the bovine adrenal medulla. These did not correspond to any of the proteins involved in the synthesis or storage of catecholamines which were considered as putative autoantigens.
Conclusion. The finding of similar frequencies of immunoglobulins binding to adrenal medulla in both type 1 and 2 diabetic patients as well as in normal controls, argues against a role of anti-adrenomedullary antibodies in the pathogenesis of autonomic diabetic neuropathy.     

Reversible Redox Property of Co(III) in Amorphous Co-Doped SiO2/γ-Al2O3 Layered Composites

This paper reports on a unique reversible reducing and oxidizing (redox) property of Co(III) in Co-doped amorphous SiO₂/γ-Al₂O₃ composites. The Fenton reaction during the H₂O₂-catalyzed sol–gel synthesis utilized in this study lead to the partial formation of Co(III) in addition to Co(II) within the composites. High-resolution transmission electron microscopy (HRTEM) and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) analyses for the composite powder sample with a composition of Al:Si:Co = 85:10:5 showed the amorphous state of the Co-doped SiO₂ that modified γ-Al₂O₃ nanocrystalline surfaces. In situ X-ray absorption fine structure (XAFS) spectroscopic analysis suggested reversible redox reactions of Co species in the composite powder sample during heat-treatment under H₂ at 500 °C followed by subsequent cooling to RT under Ar. Further analyses by in situ IR spectroscopy combined with cyclic temperature programmed reduction/desorption (TPR/TPD) measurements and X-ray photoelectron spectroscopic (XPS) analysis revealed that the alternating Co(III)/(II) redox reactions were associated with OH formation (hydrogenation)-deformation (dehydrogenation) of the amorphous aluminosilicate matrix formed in situ at the SiO₂/γ-Al₂O₃ hetero interface, and the redox reactions were governed by the H₂ partial pressure at 250–500 °C. As a result, a supported mesoporous γ-Al₂O₃/Co-doped amorphous SiO₂/mesoporous γ-Al₂O₃ three-layered composite membrane exhibited an H₂-triggered chemical valve property: mesopores under H₂ flow (open) and micropores under He flow (closure) at 300–500 °C.     

FTO gene variants are strongly associated with type 2 diabetes in South Asian Indians

Aims and hypothesis  Variants of the FTO (fat mass and obesity associated) gene are associated with obesity and type 2 diabetes in white Europeans, but these associations are not consistent in Asians. A recent study in Asian Indian Sikhs showed an association with type 2 diabetes that did not seem to be mediated through BMI. We studied the association of FTO variants with type 2 diabetes and measures of obesity in South Asian Indians in Pune. Methods  We genotyped, by sequencing, two single nucleotide polymorphisms, rs9939609 and rs7191344, in the FTO gene in 1,453 type 2 diabetes patients and 1,361 controls from Pune, Western India and a further 961 population-based individuals from Mysore, South India. Results  We observed a strong association of the minor allele A at rs9939609 with type 2 diabetes (OR per allele 1.26; 95% CI 1.13–1.40; p = 3 × 10⁻⁵). The variant was also associated with BMI but this association appeared to be weaker (0.06 SDs; 95% CI 0.01–0.10) than the previously reported effect in Europeans (0.10 SDs; 95% CI 0.09–0.12; heterogeneity p = 0.06). Unlike in the Europeans, the association with type 2 diabetes remained significant after adjusting for BMI (OR per allele for type 2 diabetes 1.21; 95% CI 1.06–1.37; p = 4.0 × 10⁻³), and also for waist circumference and other anthropometric variables. Conclusions  Our study replicates the strong association of FTO variants with type 2 diabetes and similar to the study in North Indians Sikhs, shows that this association may not be entirely mediated through BMI. This could imply underlying differences between Indians and Europeans in the mechanisms linking body size with type 2 diabetes. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorised users. C. S. Janipalli, S. Bhaskar, S. R. Kulkarni and R. M. Freathy contributed equally to this study.     

Successful combined use of tranexamic acid and unfractionated heparin for life-threatening bleeding associated with intravascular coagulation in a patient with chronic myelogenous leukemia in blast crisis

The current therapeutic strategy for disseminated intravascular coagulation (DIC) is limited to control of the underlying disease, and methods for the effective management of DIC have not been established. We report the successful use of tranexamic acid (TA) combined with unfractionated heparin in a patient with life-threatening bleeding from the sigmoid colon caused by DIC. A 35-year-old man who had undergone allogeneic bone marrow transplantation for chronic myelogenous leukemia was referred for relapse of his leukemia. The patient was first treated with imatinib at 600 mg/day. Although the disappearance of leukemic cells and a decrease in the BCR/ABL fusion gene were observed, he developed massive bleeding from the sigmoid colon after defecation. A laboratory diagnosis of DIC with prominent fibrinolysis was based on elevated levels of both plasmin-alpha2-plasmin inhibitor complex and thrombin-antithrombin III complex. Despite vigorous supportive therapy, including multiple transfusions and aggressive fluid resuscitation, the patient developed hypovolemic shock due to the uncontrollable bleeding. TA combined with unfractionated heparin was instituted to inhibit excessive fibrinolysis. A prompt response was observed soon after the commencement of therapy. No organ dysfunction was observed throughout TA and heparin use. To our knowledge, this report is the first to describe successful treatment with TA combined with heparin for life-threatening intestinal bleeding due to acute DIC associated with hematologic malignancy.