Plasma homocysteine concentrations in type II diabetic patients in India: relationship to body weight

Autoimmunity, insulin resistance and Beta cell function in subjects with low body weight type 2 diabetes mellitus

In developing countries like India, the majority of Type 2 diabetics are non-obese, and many are "lean" with a body mass index (BMI) below 18.5. This type is referred to as "Low Body Weight Type 2 DM" (LB Type 2 DM). LB Type 2 DM are confused with Type 1 DM or late autoimmune diabetes in adults (LADA) due to their high blood glucose levels and early insulin-requiring state. We assessed pancreatic islet cell autoimmunity by using both glutamic acid decarboxylase 65 antibody (GADA) and anti-IA(2) antibody estimation in 23 patients with LB Type 2 DM and 10 age-matched normal weight (NW) Type 2 DM. Fasting blood glucose (FBG) and 2 hr postchallenge blood glucose (PGBG2) were significantly higher in LB (p < 0.05), while mean values of fasting insulin (24.47 +/- 73.15 muIU/mL vs. 13.4 +/- 16.54 muIU/mL, p > 0.7) and fasting C-peptide (180.81 +/- 357.08 pM/mL vs. 279.83 +/- 281.38 pM/mL, p > 0.5) in LB and NW respectively were not statistically different. All 23 LB and 10 NW subjects were GADA negative while IA(2) positivity was found in 1/23 and 1/10 cases, respectively. LB Type 2 DM revealed good beta cell function with homeostasis model assessment beta cells (HOMAB) values of 57.41 +/- 153.18 as compared to 44.74 +/- 56.24 (p > -0.2) in NW Type 2 DM. Insulin resistance as assessed by homeostasis model assessment insulin resistant (HOMA IR) was 13.50 +/- 42.83 and 5.68 +/- 6.90 (p > 0.6) in LB and NW Type 2 DM, respectively, suggesting that LB Type 2 DM are a phenotypic variant of Type 2 DM.

Plasma Homocysteine and Insulin in Diabetic Nephropathy: Relationship to Body Mass Index

The data on plasma homocysteine and endogenous insulin in type 2 diabetes mellitus with nephropathy and relationship to body mass index (BMI) is particularly from the Indian subcontinent. A prospective study was carried out in 50 patients of type 2 diabetes mellitus with overt nephropathy (Group A). The results were compared with 25 diabetics without nephropathy (Group B), and 25 age and sex matched healthy controls (Group C). Microenzyme immunoassay and ELISA estimated the plasma homocysteine and insulin, respectively. The mean values of plasma homocysteine were significantly elevated in diabetic nephropathy (21.3+/-7.2 micromol/L) and diabetics without nephropathy (19.4+/-7.1) when compared to healthy control (11.5+/-2.3). The insulin levels and BMI were significantly higher in diabetics as compared to controls. There was no correlation between homocysteine and insulin, homocysteine and BMI, and homocysteine with the degree of renal failure.

Plasma homocysteine and polycystic ovary syndrome: The missed link

OBJECTIVE

The objective was to investigate the relationship between insulin resistance and increased serum homocysteine in women with polycystic ovarian syndrome (PCOS).

DESIGN

Prospective controlled trial.

SETTING

Department of Obstetrics & Gynecology, Mansoura Faculty of Medicine, Mansoura, Egypt.

PATIENTS

Ninety PCOS women as a study group and 35 women with infertility due to other causes as a control group.

OUTCOME MEASURES

Serum homocysteine levels in the presence and absence of insulin resistance in PCOS patients.

RESULTS

Homocysteine levels were significantly higher in PCOS patients than in the controls. Considering 11 micromol/l as the cut-off level for a normal homocysteine level, 41.1% of PCOS patients (37 out of 90) and 2.9% of control group (1 out of 35) had high homocysteine levels. With regard to insulin resistance, 23% of PCOS patients without insulin resistance (9 out of 39) had a high homocysteine level, while 47% of PCOS patients with insulin resistance (24 out of 51) had this, thus demonstrating the effect of insulin resistance on the homocysteine level.

CONCLUSION

There is a strong association between serum homocysteine and insulin resistance in women with PCOS that contributes to the long-term complications of PCOS.

Increased serum leptin concentrations in patients with chronic stable angina pectoris and ST-elevated myocardial infarction

Leptin is an adipocytokine that is produced mainly by adipose tissue; it is also identified in atherosclerotic lesions in human coronary atherosclerosis. However, the relation of serum leptin concentrations to ischemic heart disease (IHD) is still obscure. The aims of the present study were to investigate serum leptin concentrations in patients with ST-elevated myocardial infarction (STEMI) and with chronic stable angina pectoris (CSAP) and to evaluate the possible correlations of leptin to other atherosclerotic risk factors; including serum high sensitive C-reactive protein (Hs-CRP), serum homocysteine, and fibrinogen concentrations. For this purpose, 35 patients with CSAP, 40 with acute STEMI, and 30 control subjects with normal findings from coronary angiography were taken into the study prospectively. Serum leptin concentrations were significantly higher in patients with CSAP and STEMI compared to the control group (7.74 +/-1.34 vs 6.37 +/-1.85 ng/mL, p=0.021 and 8.22 +/-3.13 vs 6.37 +/-1.85 ng/mL, p=0.023, respectively). In addition, serum homocysteine concentrations were significantly increased in patients with CSAP (15.23 +/-5.96 vs 11.40 +/-2.11 micromol/L, p=0.025) and patients with STEMI (15.90 +/-5.02 vs 11.40 +/-2.11 micromol/L, p=0.012) compared to the control group. Serum fibrinogen concentrations were significantly increased only in the CSAP group as compared to controls (4.15 +/-1.39 vs 3.45 +/-1.19 g/L, p=0.025). No significant correlation was found between leptin levels and selected risk factors. In conclusion, serum leptin concentrations were significantly higher in both the CSAP and STEMI groups. However, owing to the lack of correlation between the leptin levels and selected classical coronary risk factors, it may be considered that leptin can be evaluated as one of the independent risk factors for IHD. Further randomized and controlled studies will be required to determine the pathophysiological meaning of the increased leptin levels and the central role between adipocyte function and atherosclerosis.

Total homocysteine levels relation with chronic complications of diabetes, body composition, and other cardiovascular risk factors in a population of patients with diabetes mellitus type 2

OBJECTIVE

The significance of hyperhomocysteinemia in type 2 diabetes is further complicated by the multiple ways of considering impaired renal function and vitamin status. The aim of our study was to analyze the relationship between total homocysteine (tHcy) in a population of type 2 diabetic patients and chronic complications. We also analyzed the relationship between tHcy and the body composition of these patients and other cardiovascular risk factors.

DESIGN

In a cross-sectional study, a total of 155 patients with diabetes mellitus attending in our diabetes service (90 females/65 males) were enrolled in a consecutive way.

MATERIAL AND METHODS

All enrolled patients underwent the following examinations: (i) biochemical cardiovascular risk factors including total cholesterol, triglyceride, lipoprotein (a), low-density lipoprotein (LDL-cholesterol), high-density lipoprotein (HDL-cholesterol), glucose, HbA(1c), fibrinogen, homocysteine, vitamin B12, folate, and microalbuminuria; and (ii) fat mass assessed by body mass index, weight, percentage of fat mass, and tricipital skinfold.

RESULTS

Patients were divided in two groups (Group I: tHcy> or =15 micromol/l; Group II: tHcy<15 micromol/l). Smoking habit was similar in both groups. A prevalence of cerebrovascular accident was present in 3.3% in the total group. This prevalence was not different in both groups (7.4% vs. 2.3%; ns) (OR 3.3; 95% CI 0.49-19.68). The prevalence of coronary heart disease in the total group was 5.8% without statistical differences between groups (3.5% vs. 6.3%; ns) (OR 0.57; 95% CI 0.065-4.53). Concerning macrovascular complications, only peripheral vascular disease prevalence was higher in Group I (16% vs. 3.1%; P<0.05; OR 5.33; 95% CI 1.18-21.5). A prevalence of nephropathy was higher in Group I (93.3% vs. 12.8%; P<0.05; OR 7.15; 95% CI 2.9-17.9). No statistical differences were detected in prevalence of retinopathy (global group 41.9%) (42.5% vs. 40.9%; ns) (OR 1.75; 95% CI 0.78-3.9). Also, peripheral neuropathy was similar in both groups (7.1% vs. 6.5%; ns) (OR 1.1; 95% CI 0.15-8.2). No correlation was detected among homocysteine and anthropometric parameters (body mass index, weight, percentage of fat mass, fat mass, and tricipital skinfold). Elevated levels of fibrinogen, lipoprotein (a), microalbuminuria, and blood pressure were detected in Group I.

CONCLUSION

The present study shows that elevation of plasma tHcy levels in type 2 diabetic patients is associated with a higher prevalence of peripheral arteriopathy and nephropathy. Our data suggest that hyperhomocysteinemia is not associated with fat mass but it is associated with high levels of fibrinogen, lipoprotein (a), microalbuminuria, and blood pressure levels.

Thiols, malonaldehyde and total antioxidant status in the Turkish patients with type 2 diabetes mellitus

Non-insulin dependent (Type 2) diabetes mellitus (NIDDM) is a risk factor for cardiovascular diseases (CVD). Oxidative stress mechanisms are often reported to be implied in type 2 diabetes mellitus. In order to determine their clinical relevance, we investigated several plasma indicators in the Turkish patients with NIDDM: (i) homocysteine (Hcy) and cysteine (Cys) which contribute to increase the risk of atherosclerosis during NIDDM, (ii) glutathione (GSH) and cysteinylglycine (CysGly) resulting from GSH degradation catalyzed by gamma-glutamylcysteine transferase (GGT), (iii) malonaldehyde (MDA) as a marker for lipid peroxidation, and (iv) total antioxidant status (TAS). Our main results were evaluated based on sex and diabetic status. In female patients, plasma concentrations of MDA and Hcy were significantly higher than in controls, while GSH levels were significantly lower. In males, a difference between control and diabetic groups was noticed only for Hcy, levels being also higher in patients. In the diabetic group, increase in serum glucose concentration was significantly correlated with increased GGT activity. In both controls and diabetic patients, GGT activity was correlated with a raised Cys concentration and a decreased GSH level. In both controls and diabetic patients, there were significant positive correlations between Cys and Hcy and between GSH and Hcy. We concluded that GSH and MDA levels are clinical indicators for an oxidative process linked to type 2 diabetes mellitus, especially in women.

Involvement of leptin in the association between percentage of body fat and cardiovascular risk factors

OBJECTIVES

Recent epidemiologic studies have shown that obesity is associated with elevated blood concentrations of prothrombotic-proinflammatory factors and markers of endothelial dysfunction such as fibrinogen, C-reactive protein (CRP), von Willebrand factor (vWF), and homocysteine. We have assessed whether these markers are associated with percentage of body fat (BF), insulin sensitivity as well as with leptin concentrations.

DESIGN AND METHODS

Twenty-five men aged 49.6 +/- 12.7 yr (mean +/- SD) underwent whole-body air displacement plethysmography (Bod-Pod(R)) for estimating BF. Blood analyses for leptin and several other metabolic and cardiovascular markers were carried out.

RESULTS

Obese subjects had higher levels as compared to controls of BF (37.5 +/- 5.1 vs. 26.0 +/- 6.6, p < 0.01), fibrinogen (3.30 +/- 0.43 vs. 2.67 +/- 0.11, p < 0.01), vWF (136.4 +/- 50.4% vs. 81.6 +/- 12.6%, p < 0.05), and leptin (17.6 +/- 8.7 vs. 6.2 +/- 3.3, p < 0.01), lower concentrations of HDL-cholesterol (1.09 +/- 0.20 vs. 1.51 +/- 0.10, p < 0.001) and lower QUICKI (1/[log(Ins(0)) + log(Glu(0))]) (0.31 +/- 0.03 vs. 0.34 +/- 0.02, p < 0.05). No significant changes were observed in CRP (5.7 +/- 3.4 vs. 3.8 +/- 1.6, p = 0.327) and homocysteine (9.4 +/- 4.2 vs. 8.3 +/- 0.9, p = 0.749). A positive correlation was observed between BF and fibrinogen (r = 0.67, p = 0.0003). Plasma leptin concentrations were correlated with fibrinogen (r = 0.71, p = 0.0001) and CRP (r = 0.43, p = 0.044). After adjustment for BF leptin emerged as a significant predictor of fibrinogen (beta = 0.47, p = 0.023; R(2) = 0.59, p < 0.001). QUICKI was positively correlated with HDL-cholesterol (r = 0.59, p = 0.010) and negatively with fibrinogen (r = -0.53, p = 0.025), CRP (r = -0.52, p = 0.028) and vWF (r = -0.56, p = 0.013).

CONCLUSIONS

Increased BF and impaired insulin sensitivity are associated with increased concentrations of cardiovascular risk factors. Leptin seems to be involved in this elevation and emerges as a predictor of circulating fibrinogen concentrations.

Serum homocysteine concentration is related to diabetes mellitus, but not to coronary heart disease, in Saudi Arabians

INTRODUCTION

Plasma homocysteine (HCYS) concentration is believed to be an independent risk factor for atherosclerosis.

METHODS

HCYS was measured in a cohort of 584 Saudi Arabians participating in a national screening study of coronary heart disease (CHD) risk factors. A total of 173 subjects (114 men and 59 women) had clinical CHD, of whom 82 (47.4%) had type 2 diabetes mellitus (56 men and 26 women). A further 127 subjects (60 men and 67 women) also had type 2 diabetes mellitus but no CHD. A total of 284 individuals (120 men and 164 women) were recruited as healthy controls, and had no previous history of CHD or diabetes. Serum HCYS was measured by high-performance liquid chromatography (HPLC) with electrochemical detection.

RESULTS

Univariate analysis showed HCYS concentrations were significantly lower in those with diabetes mellitus (DM) than in controls, for both men [8.7 (4.2-18.6) vs. 10.5 (4.5-20.5) mmol/l, median (5th-95th percentiles, p = 0.009] and women [6.3 (3.3-24.0) vs. 8.1 (4.0-17.9) mmol/l, p = 0.049]. Stepwise multivariate regression analysis indicated a relationship between HCYS concentration and age, sex and the presence of DM, but not with CHD.

CONCLUSIONS

In the Saudi Arabian population, serum HCYS is not a risk factor for CHD, but is lower in patients with DM.

Methylenetetrahydrofolate reductase polymorphism, type II diabetes mellitus, coronary artery disease, and essential hypertension in the Czech population

Increased plasma concentrations of homocysteine have been found in patients with coronary artery disease (CAD) and essential hypertension (EH) and in patients with diabetic complications. The 677C/T methylenetetrahydrofolate reductase (MTHFR) gene polymorphism is related to the MTHFR enzyme activity and to the plasma homocysteine concentration. This study was designed to investigate an association of this polymorphism with CAD, EH, and type II diabetes mellitus in the Czech population. The MTHFR genotypes were assessed by the polymerase chain reaction-based methodology in a sample of 1199 unrelated Caucasian subjects with CAD, EH, type II diabetes, or a combination of these diseases, and in healthy subjects. Allele frequencies of the MTHFR polymorphism differed considerably between women with and without type II diabetes mellitus (P = 0.00069), with a higher frequency of the C allele in the diabetic women. In addition, the MTHFR T allele frequency was significantly higher in normotensive subjects with CAD compared with normotensive subjects without this disease (P = 0.020). Both associations were confirmed by multiple logistic regressions. In conclusion, while the C allele of the 677C/T MTHFR polymorphism is associated with type II diabetes mellitus in women, the T allele is associated with CAD only in normotensive subjects of Czech origin.