Bone mass and bone resorption in postmenopausal women with type 2 diabetes mellitus

The aim of the present study was to examine the relationships between bone mass or bone resorption evaluated by urinary cross-linked N-telopeptides of type I collagen (NTx) concentration and known and potential contributors to bone mass or bone resorption such as sex hormones, age, duration of diabetes, glycemic control (hemoglobin A(1c) [HbA(1c)]), body mass index (BMI), severity of diabetic complications, smoking status, and current treatment of diabetes in postmenopausal women with type 2 diabetes mellitus (n = 196). In addition, the relationship of bone mass to pulse wave velocity, which is an earlier indicator of cardiovascular disease, was investigated in a subgroup of patients (n = 120). Bone mass was evaluated by the quantitative ultrasound method. A higher stiffness index indicates higher bone mass. Inverse correlations were found between the stiffness index and age (r = -0.374, P < .0001) and between the stiffness index and log (urinary albumin excretion) (r = -0.170, P = .0398), and a positive correlation was found between the stiffness index and serum dehydroepiandrosterone sulfate (DHEA-S) concentration (r = 0.201, P = .0136). No significant correlations were found between the stiffness index and duration of diabetes, HbA(1c), BMI, or serum estradiol concentration. No significant correlations were found between urinary NTx concentration and age, duration of diabetes, HbA(1c), BMI, serum estradiol concentration, or serum DHEA-S concentration. The stiffness index correlated inversely with urinary NTx concentration (r = -0.262, P = .0002). No significant correlation was found between the stiffness index and pulse wave velocity (r = -0.165, P = .0714). Multiple regression analysis demonstrated that serum DHEA-S concentration was an independent determinant of the stiffness index (beta = .207, P = .0428). In conclusion, serum DHEA-S concentration correlated positively with bone mass, whereas glycemic control, BMI, or duration of diabetes did not correlate with bone mass or urinary NTx concentration in postmenopausal women with type 2 diabetes mellitus.

Classification of adult patients with type 2 diabetes using the Temperament and Character Inventory

AIM

Adult patients with type 2 diabetes were classified using the Temperament and Character Inventory (TCI). This classification was used to propose effective therapeutic approaches based on subtypes of psychological characteristics.

METHODS

The TCI and various psychological tests were administered to 89 patients (54 men and 35 women). Cluster analysis was performed using three temperament factors of the TCI as variables for subclassification: novelty seeking (NS), harm avoidance (HA) and reward dependence (RD).

RESULTS

The patients were divided into two clusters based on the TCI results. Cluster 1 had a low NS/high HA/low RD pattern, which indicated resistance to change and lack of cooperativeness, and results of other tests indicated that patients in cluster 1 were obsessional and had weak intention and personality disorder symptoms. In contrast, cluster 2 had a high NS/low HA/high RD pattern, indicating a socially active person who easily becomes dependent on others, and results of other tests indicated that these patients were histrionic and less anxious. In cluster 1 there was a significant negative correlation between hemoglobin A1c (HbA1c) and SD-1 (TCI self-directedness) 'responsibility' and a significant positive correlation between HbA1c and State anxiety of State-Trait Anxiety Inventory. In cluster 2 there was a significant positive correlation between HbA1c and HA-2 'fear of uncertainty'.

CONCLUSIONS

Patients with type 2 diabetes were classified using the TCI into two subgroups. These two groups differed in psychological characteristics and had a different pattern in correlation with glycemic control.

Serum prostate-specific antigen levels in men with type 2 diabetes

OBJECTIVE

The aims of this study were to examine if serum prostate-specific antigen (PSA) levels are lower in men with type 2 diabetes compared with those in healthy men and to investigate what factors may be associated with serum PSA levels in men with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We compared the serum PSA levels in 224 diabetic men with those in 1,293 healthy men and investigated the relationships between serum PSA levels and various variables.

RESULTS

Except for men aged 40-49 years, serum PSA levels were lower in diabetic men than in healthy men. Multiple regression analysis demonstrated that age, BMI, and presence of diabetes were independent determinants of serum PSA level.

CONCLUSIONS

Serum PSA levels were lower in diabetic men compared with those in healthy men, which is in line with previous reports that patients with type 2 diabetes are at a decreased risk of prostate cancer.

Serum uric acid is associated with microalbuminuria and subclinical atherosclerosis in men with type 2 diabetes mellitus

Hyperuricemia has been reported to be associated with increased risk of renal insufficiency as well as cardiovascular events. The aim of this study was to evaluate the relationships between serum uric acid concentration and degree of urinary albumin excretion as well as markers of subclinical atherosclerosis in men with type 2 diabetes mellitus. Serum uric acid concentrations were measured in 343 men with type 2 diabetes mellitus. We then evaluated relationships of serum uric acid concentrations to degree of urinary albumin excretion as well as to major cardiovascular risk factors, including age, blood pressure, serum lipid concentration, and glycemic control (hemoglobin A1c). The relationships between serum uric acid concentration and pulse wave velocity or ankle-brachial index (n=236) and between serum uric acid concentration and carotid intima-media thickness or plaque score (n=125) were investigated additionally in a subgroup of patients. Serum uric acid concentration correlated positively with logarithm of urinary albumin excretion (r=0.302, P<.0001). Positive correlation was found between serum uric acid concentration and intima-media thickness (r=0.233, P=.0087), whereas inverse correlation was found between serum uric acid concentration and ankle-brachial index (r=-0.150, P=.0207). Multiple regression analysis demonstrated that serum uric acid concentration (beta=.281, P<.0001), duration of diabetes (beta=.253, P<.0001), hemoglobin A1c (beta=.166, P=.0034), serum triglyceride concentration (beta=.125, P=.0472), and systolic blood pressure (beta=.275, P=.0013) were independent determinants of logarithm of urinary albumin excretion. In conclusion, serum uric acid concentration is associated with microalbuminuria and subclinical atherosclerosis in men with type 2 diabetes mellitus.

Association of killer cell immunoglobulin-like receptor genotypes with susceptibility to endometriosis

PROBLEM

Endometriosis is an immune-related chronic inflammatory disease with a polygenic predisposition. The aim of this study was to investigate whether polymorphisms in killer cell immunoglobulin-like receptors (KIRs) is responsible, in part, for genetic susceptibility to endometriosis.

METHOD OF STUDY

The KIRs genotype was determined in 186 patients with endometriosis and 165 control women using polymerase chain reaction with sequence-specific primers.

RESULTS

The frequency of KIR3DS1 was significantly decreased in patients compared with controls (32% versus 44%, P=0.028). KIR data were analyzed using a model comprised of three large groups, in which a gradient of activation/inhibitory potential derived from the combination of KIR and human leukocyte antigen (HLA) ligand genes was taken into account. The frequency of inhibitory KIRs/HLA-class I combination genotypes was significantly higher in patients than in controls (chi2=6.010, 2 df, P=0.0496).

CONCLUSION

Our results suggest that polymorphism in KIRs may be associated with susceptibility for endometriosis.

Association between serum bioavailable testosterone concentration and the ratio of glycated albumin to glycated hemoglobin in men with type 2 diabetes

OBJECTIVE

Testosterone stimulates erythropoiesis and thus glycated hemoglobin (A1C) values may be relatively low in male diabetic patients with hypogonadism. We therefore investigated relationships between serum bioavailable testosterone concentration and the ratio of glycated albumin (GA) to A1C and between serum bioavailable testosterone and hemoglobin concentrations in men with type 2 diabetes.

RESEARCH DESIGN AND METHODS

The above relationships were investigated in 222 consecutive men with type 2 diabetes. We also investigated how the ratio of GA to A1C is related to other variables such as age, BMI, and degree of diabetic microangiopathy.

RESULTS

Mean ratio of GA to A1C was 2.94 +/- 0.38. Serum bioavailable testosterone concentration correlated positively with hemoglobin concentration (r = 0.368, P < 0.0001) and negatively with the ratio of GA to A1C (r = -0.278, P < 0.0001). Multiple regression analyses identified serum bioavailable testosterone concentration (beta = 0.187, P = 0.0062), age (beta = -0.204, P = 0.0075), BMI (beta = 0.151, P = 0.0302), systolic blood pressure (beta = 0.173, P = 0.0090), and plasma total cholesterol (beta = 0.155, P = 0.0141) as independent determinants of hemoglobin concentration; moreover, serum bioavailable testosterone concentration (beta = -0.155, P = 0.0381) and plasma total cholesterol (beta = -0.170, P = 0.0144) were identified as independent determinants of the ratio of GA to A1C.

CONCLUSIONS

Serum bioavailable testosterone concentration correlated positively with hemoglobin concentration and negatively with the ratio of GA to A1C in men with type 2 diabetes, which may lead to underestimation of A1C in hypogonadal men with type 2 diabetes.

Association between serum estradiol concentrations and carotid atherosclerosis in men with type 2 diabetes mellitus

The aim of this study was to evaluate relationships between serum estradiol concentration and carotid atherosclerosis in addition to major cardiovascular risk factors in men with type 2 diabetes mellitus because previous reports concerning the role of estrogen on atherosclerosis in men are conflicting. Serum estradiol concentrations were measured in 305 consecutive men with type 2 diabetes mellitus. Relationships were evaluated between serum estradiol concentration and carotid atherosclerosis, as determined by ultrasonographically evaluated intima-media thickness (IMT) and plaque score, in a subgroup of 144 diabetic patients, as well as major cardiovascular risk factors, including age, blood pressure, and lipid concentrations. An inverse correlation was found between serum estradiol concentration and IMT (r = -0.174, P = .0369), but no correlation was found between serum estradiol concentration and plaque score. Patients with serum estradiol concentrations in the lowest tertile displayed significantly higher IMT compared with patients in the highest tertile (P = .0083). Serum estradiol concentration was not a determinant of IMT (beta = -.121, P = .1396) in the multiple regression analysis. An inverse correlation was found between serum estradiol concentration and triglyceride concentration (r = -0.136, P = .0186). In conclusion, serum estradiol concentration is inversely associated with carotid atherosclerosis as determined by ultrasonographically evaluated IMT in men with type 2 diabetes mellitus.

Joint effect of alcohol and usual sleep duration on the risk of dysglycemia

STUDY OBJECTIVES

Sleep duration and alcohol use influence metabolic function. However, limited information exists regarding a combined effect of alcohol and sleep duration on glucose metabolism. The aim of this study was to assess the potential interaction effect of alcohol and inappropriate sleep duration on dysglycemia epidemiologically.

DESIGN

Cross-sectional and observational retrospective study.

SETTING

A medical health checkup program in a general hospital.

PARTICIPANTS

2933 apparently healthy Japanese individuals, aged 46 to 60 years.

INTERVENTION

N/A.

MEASUREMENTS AND RESULTS

We examined the relationships between usual sleep duration and dysglycemia, and furthermore assessed the combined effects of alcohol consumption and sleep time on glucose dysmetabolism. A U-shaped relationship between sleep duration and the prevalence of hyperglycemia (fasting plasma glucose level > or =110 mg/dL) was observed when sleep duration was treated as a continuous variables and centered at 7.0 h (quadratic term P = 0.024). In a multivariate quadratic regression model, there was a significant interaction effect between sleep duration and alcohol consumption category (nondrinkers, light-moderate drinkers [ethanol comsumption < or =210 g/wk], and heavy drinkers [ethanol consumption of >210 g/wk]) on fasting plasma glucose levels, with shorter or longer sleep duration being more diabetogenic in individuals who consumed more alcohol (P interaction = 0.018). Furthermore, we found a similar interaction effect of sleep duration and alcohol consumption on the incidence of hyperglycemia during the past 5 years (P interaction = 0.039).

CONCLUSION

Alcohol interacts with reduced sleep duration to increase the risk of dysglycemia.

Low serum testosterone concentration in middle-aged men with type 2 diabetes

Low concentrations of endogenous androgens have been linked with insulin resistance and atherosclerosis. Men with diabetes have been reported to have lower serum testosterone concentration than non-diabetic men; however, there has never been a large study. The aim of this study was to investigate if endogenous androgen concentration is certainly lower in a relatively large number of Japanese patients with type 2 diabetes compared with healthy men, and to identify what factors may be associated with low serum testosterone concentrations in men with type 2 diabetes. Serum free testosterone concentrations were measured in 524 healthy men and in 331 consecutive Japanese men with type 2 diabetes between 40 and 69 years old. In addition, we investigated the relationships between serum free testosterone concentration and luteinizing hormone (LH) concentration as well as major cardiovascular risk factors including age, blood pressure, plasma lipid concentration, glycemic control (HbA(1c)), and BMI. Serum free testosterone concentrations were lower in men with type 2 diabetes than in healthy men in the 40-49 years group (10.9 +/- 3.3 vs. 14.0 +/- 3.6 pg/ml, P<0.0001), in the 50-59 years group (10.4 +/- 3.2 vs. 12.1 +/- 2.9 pg/ml, P<0.0001), and in the 60-69 years group (9.5 +/- 2.6 vs. 10.5 +/- 2.9 pg/ml, P = 0.0104). A negative correlation was found between serum free testosterone and LH concentrations (r = -0.326, P<0.0001). In conclusion, serum free testosterone concentration is certainly lower in a relatively large number of Japanese patients with type 2 diabetes compared with healthy men with each decade of life between 40 and 69 years old.

Relationship between low serum endogenous androgen concentrations and arterial stiffness in men with type 2 diabetes mellitus

The aim of this study was to evaluate the relationship between arterial stiffness determined by pulse wave velocity (PWV) and serum endogenous androgen concentrations as well as major cardiovascular risk factors in men with type 2 diabetes mellitus. Serum free testosterone and dehydroepiandrosterone sulfate (DHEA-S) concentrations were measured in 268 men with type 2 diabetes mellitus. Relationships between PWV and serum endogenous androgen concentrations as well as major cardiovascular risk factors, including age, blood pressure, serum lipid concentration, glycemic control (hemoglobin A(1c)), body mass index, and degree of albuminuria, were evaluated. Positive correlations were found between PWV and age (r = 0.491, P < .0001), duration of diabetes (r = 0.320, P < .0001), systolic blood pressure (r = 0.292, P < .0001), and log (urinary albumin excretion) (r = 0.269, P < .0001). Inverse correlations were found between serum free testosterone concentration and PWV (r = -0.228, P = .0003) and between serum DHEA-S concentration and PWV (r = -0.252, P = .0002) in men with type 2 diabetes mellitus. Pulse wave velocity was significantly greater in patients with lower concentrations of free testosterone (<10 pg/mL) than in patients with higher concentrations of free testosterone (1864 +/- 359 vs 1736 +/- 327 cm/s; P = .0053). Pulse wave velocity also was significantly greater in patients with lower concentrations of DHEA-S (<1000 ng/mL) than in patients with higher concentrations of DHEA-S (1843 +/- 371 vs 1686 +/- 298 cm/s; P = .0008). Multiple regression analysis identified both serum free testosterone concentration (beta = -.151, P = .0150) and serum DHEA-S concentration (beta = -.200, P = .0017) as independent determinants of PWV. In conclusion, serum endogenous androgen concentrations are inversely associated with arterial stiffness determined by PWV in men with type 2 diabetes mellitus, which is true for men in general based on other works.

Association between serum testosterone concentration and collagen degradation fragments in men with type 2 diabetes mellitus

The aim of the present study was to evaluate relationships between serum endogenous androgens and urinary concentration of cross-linked N-telopeptides of type I collagen (NTx), a bone resorption marker, in men with type 2 diabetes mellitus because low androgen concentrations are associated with both osteoporosis and cardiovascular disease. Relationships between serum free testosterone and urinary NTx concentrations were investigated in 246 consecutive men with type 2 diabetes mellitus. In addition, relationships between urinary NTx concentration and other variables including age, duration of diabetes, blood pressure, serum lipid concentration, hemoglobin A(1c), and body mass index were evaluated. Urinary NTx concentrations were 27.8 (26.4-29.3) nmol of bone collagen equivalent per millimole of creatinine, correlating inversely with serum free testosterone (r = -0.263, P < .0001). Multiple regression analysis identified serum free testosterone (beta = -.292, P < .0001), hemoglobin A(1c) (beta = .144, P = .0404), and smoking status (beta = .143, P = .0402) as independent determinants of urinary NTx. In conclusion, serum free testosterone concentration correlated inversely with urinary NTx concentration, which may partly account for an observed link between osteoporosis and cardiovascular disease in men with type 2 diabetes mellitus.

Metabolic syndrome is not associated with markers of subclinical atherosclerosis, serum adiponectin and endogenous androgen concentrations in Japanese men with Type 2 diabetes

AIMS

Metabolic syndrome is characterized by its association with certain cardiovascular disease risk factors. The aim of this study was to investigate the relationships between metabolic syndrome and markers of subclinical atherosclerosis, serum adiponectin and endogenous androgen concentrations in Japanese men with Type 2 diabetes.

METHODS

Using the 2005 International Diabetes Federation (IDF) definition, we assessed the prevalence of the metabolic syndrome in 424 consecutive men with Type 2 diabetes aged 40-75 years in a cross-sectional study. We compared characteristics including ultrasonographic carotid atherosclerosis markers, pulse-wave velocity (PWV), and serum adiponectin, free testosterone, and dehydroepiandrosterone sulphate (DHEA-S) concentrations in diabetic patients with and without the metabolic syndrome.

RESULTS

The prevalence of the metabolic syndrome in Japanese men with Type 2 diabetes was 46.9%. Men with the metabolic syndrome had higher urinary albumin excretion rate than those without. Carotid intima-media thickness (0.97 +/- 0.26 vs. 0.91 +/- 0.18 mm), plaque score [3.3 (1.5-8.1) vs. 3.8 (1.3-6.2)], PWV (1818 +/- 331 vs. 1749 +/- 331 cm/s) and ankle-brachial index (1.10 +/- 0.14 vs. 1.08 +/- 0.16) did not differ significantly between patients with and without the metabolic syndrome. Similarly, serum adiponectin [3.70 (2.06-6.09) vs. 4.65 (3.09-7.02) microg/ml], free testosterone (36.4 +/- 10.7 vs. 34.7 +/- 11.1 pmol/l), and DHEA-S concentrations (3.29 +/- 1.83 vs. 3.17 +/- 1.63 micromol/l) did not differ significantly between groups,

CONCLUSIONS

The metabolic syndrome, as defined by the IDF, is not significantly associated with subclinical atherosclerosis markers, serum adiponectin, or endogenous androgen concentrations in Japanese men with Type 2 diabetes.

Angiotensin II receptor blocker inhibits abnormal accumulation of advanced glycation end products and retinal damage in a rat model of type 2 diabetes

The effects of an angiotensin II receptor blocker (ARB) on the accumulation of one of advanced glycation end products (AGEs), pentosidine, expression of vascular endothelial growth factor (VEGF) and retinal function were investigated in Spontaneously Diabetic Torii (SDT) rats. Candesartan, an ARB, was administered to SDT rats from 10 to 44 weeks of age and the results compared with untreated SDT rats and SD rats. Electroretinograms (ERGs) were recorded to evaluate retinal function. At 44 weeks of age, pentosidine was quantified in the vitreous, lens and plasma using high-performance liquid chromatography (HPLC). Real-time reverse transcription-PCR (RT-PCR) analysis was also performed in order to measure VEGF mRNA expression in the retina. Histological changes were examined and immunohistochemistry for pentosidine performed on the retina and retinal microvasculature. In untreated SDT rats, the amplitudes of a- and b-waves, oscillatory potentials were reduced significantly at 44 weeks of age compared with the 10-week levels, whereas they remained unchanged in SDT rats treated with candesartan. The concentration of pentosidine in the vitreous and lens did not change in treated SDT rats but increased in untreated SDT rats. Retinal VEGF mRNA expression was inhibited in treated SDT rats. Histologically, proliferative tissue was detected around the optic disc, with pentosidine being detected only in untreated SDT rats. Our findings indicate the ARB may inhibit the development of diabetic retinopathy by reducing the accumulation of pentosidine, one of AGEs and expression of VEGF in the retina.

Relationship of serum brain-derived neurotrophic factor level with other markers of disease severity in patients with atopic dermatitis

Elevated serum levels of neurotrophins such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) have been reported in allergic and autoimmune diseases. The aim of this study was to assess serum levels of BDNF in patients with atopic dermatitis (AD) and to investigate the relationship of the BDNF level with other markers of disease severity. Serum BDNF concentration was significantly higher in patients with AD (n=62) compared to control subjects (n=20) (P<0.01). Stepwise multiple regression analysis showed a significant influence of the peripheral blood eosinophil counts (F=6.90) and the percentage of CD4(+)IL-4(+) (Th2) cells (F=6.61). Moreover, after remission of AD patients with conventionally treated AD patients (n=14), serum levels of BDNF, eosinophil counts and percentage of Th2 cells were decreased significantly. These results suggest that serum BDNF may be a useful marker of disease activity in AD and that both eosinophils and Th2 cells are major cellular sources of serum BDNF.

Role of endogenous androgen against insulin resistance and athero- sclerosis in men with type 2 diabetes

Age-related decline in serum testosterone and dehydroepiandrosterone sulfate concentrations occur in men. Low concentrations of these endogenous androgens have been linked with insulin resistance, which is an important upstream driver for metabolic abnormalities such as hyperglycemia, hypertension, or hyperlipidemia, and increased cardiovascular risk. Moreover, men with diabetes have significantly less circulating androgen than nondiabetic men. Here, we summarize how androgen affects insulin resistance and atherosclerosis in men with type 2 diabetes. Low serum concentrations of endogenous androgens are associated with visceral fat accumulation. Androgen deprivation by castration to treat prostate cancer increases insulin resistance, while testosterone administration in type 2 diabetic men with androgen deficiency improves glucose homeostasis and decreases visceral fat, in addition to alleviating symptoms of androgen deficiency including erectile dysfunction. Androgen correlates inversely with severity of atherosclerosis and has beneficial effects upon vascular reactivity, inflammatory cytokine, adhesion molecules, insulin resistance, serum lipids, and hemostatic factors. Because men with type 2 diabetes have relative hypogonadism, testosterone supplementation could decrease both insulin resistance and atherosclerosis.

Differential regulation of intracellular redox state by extracellular matrix proteins in glomerular mesangial cells: potential role in diabetic nephropathy

Advanced diabetic nephropathy is characterized by abnormal synthesis of extracellular matrix (ECM) proteins, such as collagen I (COL I). The present experiments were designed to test the hypothesis that the presence of abnormal ECM proteins may be responsible for increased generation of reactive oxygen species (ROS) that are thought to have an important role in the pathogenesis of diabetic nephropathy. SV40 MES 13 murine mesangial cells were plated on COL I or collagen IV (COL IV) for 3 h at 5.5 or 25 mM D-glucose concentration. Increased intracellular ROS generation and reduced intracellular nitric oxide (NO) production was measured in cells attached to COL I compared with cells attached to COL IV. Treatment with N(omega)-nitro-L-arginine methyl ester hydrochloride (L-NAME), an inhibitor of NO synthase, reduced this difference in ROS generation between cells attached to either COL I or IV. The results using antibodies against integrins also indicated that an alpha(2) integrin-mediated pathway was involved in the different response in ROS generation caused by ECM proteins. These results suggest that contact between altered ECM proteins that are present in advanced diabetic nephropathy and mesangial cells has the potential to increase intracellular oxidative stress, leading to progressive glomerular damage.

Synergistic effect of interleukin-6 promoter (IL6 -634C/G) and intercellular adhesion molecule-1 (ICAM-1 469K/E) gene polymorphisms on the risk of endometriosis in Japanese women

PROBLEM

Endometriosis is an immune-related, chronic inflammatory disease with a polygenic predisposition. The aim of this study was to investigate whether the interleukin-6 (IL-6) gene promoter region polymorphism (-634C/G) and the intercellular adhesion molecule-1 (ICAM-1) gene 469K/E polymorphism are responsible in part for the genetic susceptibility to endometriosis.

METHODS OF STUDY

The IL-6 -634C/G and ICAM-1 469K/E genotypes were determined in 202 patients with endometriosis and 236 control women by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

There were no differences in the IL-6 -634C/G or the ICAM-1 469K/E genotypes and allele frequencies between control women and endometriosis patients collectively, or between control women and each clinical subgroup of endometriosis patients. Interestingly, the frequency of ICAM-1 EE homozygotes who concomitantly carried the IL-6 -634G allele was significantly higher in patients with endometriosis (chi(2) = 6.458, P = 0.0396, d.f. = 2).

CONCLUSION

Our results suggest that the IL-6 -634C/G and ICAM-1 469K/E polymorphisms synergistically affect the susceptibility for endometriosis in the Japanese population.

Low serum dehydroepiandrosterone sulfate concentration is a predictor for deterioration of urinary albumin excretion in male patients with type 2 diabetes

We recently found that serum dehydroepiandrosterone sulfate (DHEA-S) concentration correlated inversely with the degree of urinary albumin excretion in a cross-sectional study. We therefore performed an observational study to investigate the relationship between serum DHEA-S concentrations and changes in urinary albumin excretion in male patients with type 2 diabetes to answer the question as to whether DHEA is a causal rather than simply coincidental intermediate linking urinary albumin excretion to cardiovascular disease (CVD). The relationship between serum DHEA-S concentration and changes in urinary albumin excretion was investigated in 207 consecutive male patients with type 2 diabetes. Baseline serum DHEA-S concentration and urinary albumin excretion were measured in 2003. After 12 months, urinary albumin excretion was measured and any changes in urinary albumin excretion were calculated. Patients were divided into tertiles according to DHEA-S concentration. Greater changes in urinary albumin excretion were seen in patients with low DHEA-S concentration (29.6+/-7.6mg/g creatinine) than in patients with high DHEA-S concentration (5.1+/-3.6mg/g creatinine, P=0.0091). An inverse correlation was observed between serum DHEA-S concentration and changes in urinary albumin excretion (r=-0.193, P=0.0052). Multiple regression analysis demonstrated that HbA1c (beta=0.241, P=0.0009), and serum DHEA-S concentration (beta=-0.195, P=0.0054) were independent determinants of changes in urinary albumin excretion. In conclusion, serum DHEA-S concentration was inversely correlated with changes in urinary albumin excretion, which may indicate causality in the increased CVD mortality in male patients with type 2 diabetes and low DHEA-S concentration.

Relationship between insulin resistance and inflammatory markers and anti-inflammatory effect of losartan in patients with type 2 diabetes and hypertension

BACKGROUND

It is now well established that vascular inflammation and endothelial dysfunction associated with cardiovascular diseases contributes to insulin resistance.

METHODS

We investigated the relationship between the homeostasis model assessment-insulin resistance index (HOMA-R) and various serum inflammatory markers and the effect of losartan on serum concentrations of these markers in patients with type 2 diabetes and hypertension. The patients were divided into 2 groups according to the value of HOMA-R with 60 patients with values=2.4 in Group A and 44 patients with values>2.5 in Group B. The variables were measured at baseline and after 6 months of treatment with losartan (50 mg/day).

RESULTS

The HOMA-R concentrations were positively related to TNF-alpha (r=0.336, P<0.01) and inversely related to adiponectin (r=-0.405, P<0.01) and extracellular-superoxide dismutase (EC-SOD) (r=-0.452, P<0.01). Stepwise multiple regression analysis showed a significant relationship between HOMA-R and adiponectin (F=8.74) and EC-SOD (F=14.39). In Group B, losartan treatment significantly increased the serum concentrations of EC-SOD and adiponectin and decreased TNF-alpha and HOMA-R.

CONCLUSION

Serum EC-SOD concentrations may be a sensitive biochemical marker of insulin resistance in patients with type 2 diabetes and hypertension and that losartan improves insulin sensitivity by increasing EC-SOD and adiponectin production and decreasing TNF-alpha production.