Value of serum glycated albumin and high-sensitivity C-reactive protein levels in the prediction of presence of coronary artery disease in patients with type 2 diabetes

Is the level of serum lactate dehydrogenase a potential biomarker for glucose monitoring with type 2 diabetes mellitus?

INTRODUCTION

Type 2 diabetes mellitus (T2DM) is a metabolic disorder due to defects in insulin secretion or insulin resistance leading to the dysfunction and damage of various organs. To improve the clinical evaluation of short-term blood glycemic variability monitoring, it is critical to identify another blood cell status and nutritional status biomarker that is less susceptible to interference. This study identifies the significance of serum lactate dehydrogenase (LDH) level among T2DM patients treated in outpatient clinics and investigates the relationship of LDH level with other variables.

METHODS

This study comprised 72 outpatients with T2DM over 20 years of age. Blood samples were collected followed by a hematological analysis of serum glycated albumin (GA), LDH, fasting blood glucose, glycosylated hemoglobin, C-peptide, and insulin antibodies (insulin Ab).

RESULTS

Serum LDH level was significantly correlated with GA (p < 0.001), C-peptide (p = 0.04), insulin Ab (p = 0.03), and thyroid-stimulating hormone (TSH) levels (p = 0.04). Hence, we performed a linear regression analysis of hematological markers. GA (p < 0.001, r² = 0.45) and insulin Ab (p < 0.001, r² = 0.40) were significantly associated with LDH level. Then, we classified patients into low (<200 U/L) and high (≥200 U/L) serum LDH level groups, respectively. GA (p < 0.001), C-peptide (p = 0.001), and TSH (p = 0.03) showed significant differences in patients with high LDH levels compared with those in patients with low LDH levels.

CONCLUSION

In conclusion, we suggested that LDH level was independent of long-term but associated with short-term blood glucose monitoring. The results indicated that changes in serum GA induced cell damage and the abnormal elevation of the serum level of LDH may occur simultaneously with glycemic variability. It has been reported that many biomarkers are being used to observe glucose variability in T2DM. However, LDH could provide a more convenient and faster evaluation of glycemic variability in T2DM.

Independent and joint effects of high-sensitivity c-reactive protein and hypoalbuminemia on long-term all-cause mortality among coronary artery disease: a prospective and multicenter cohort study

Background

High-sensitivity C-reactive protein (hs-CRP) plays an important role in hypoalbuminemia as a representative of inflammation, which is closely associated with poor prognosis among patients with coronary artery disease (CAD). The present study aimed to evaluate the independent and joint effects of high hs-CRP levels and hypoalbuminemia on long-term mortality among CAD patients.

Methods

A total of 1449 CAD patients were included from a prospective, multicenter, observational cohort study (REICIN, NCT01402232) of patients referred for coronary angiography (CAG). The primary endpoint was long-term all-cause death.

Results

During a median follow-up of 2.9 (2.0–3.0) years, a total of 107 (7.4%) patients died. The long-term mortality was higher among CAD patients with high hs-CRP levels (> 3 mg/L) than those with the low hs-CRP levels (≤ 3 mg/L; 10.7% versus 4.1%; hazard ratio [HR] 2.49; 95% confidence interval [CI] 1.48–4.17). Similarly, CAD patients with hypoalbuminemia had higher mortality than those without hypoalbuminemia (12.2% versus 4.9%; HR 1.93; 95% CI 1.20–3.08). When hs-CRP and albumin were combined, CAD patients with high hs-CRP levels (> 3 mg/L) and with hypoalbuminemia were at the highest risk of death compared with their reference group (hs-CRP ≤ 3 mg/L and albumin > 35 g/L; HR 3.79; 95% CI 1.91–7.52).

Conclusions

High hs-CRP levels and hypoalbuminemia were independently and jointly associated with long-term mortality among CAD patients. Patients with high hs-CRP levels and hypoalbuminemia had the highest risk of long-term mortality compared with other groups.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02431-6.

Expression of Circulating MicroRNAs and Myokines and Interactions with Serum Osteopontin in Type 2 Diabetic Patients with Moderate and Poor Glycemic Control: A Biochemical and Molecular Study

BACKGROUND

Cellular miRNAs are expressed in tissue fluids with sufficient amounts and were identified as potential molecular targets for studying the physiological mechanisms and correlations with many human diseases particularly diabetes. However, molecular-based changes among older adults with diabetes mellitus (DM) are rarely fully elucidated.

AIM

This study is aimed at identifying circulating miRNAs, which hold the potential to serve as biomarkers for the immune-inflammatory changes in older T2D patients with moderate and poor glycemic control status. In addition, the association of both myokines and osteopontin (OPN) levels with circulating miRNAs was identified.

METHODS

A total of 80 subjects aged 20-80 years were invited during the period of October 2017-May 2018 to participate in this descriptive cross-sectional study. All subjects were diagnosed with T2D for more than 5 years. Subjects were grouped based on glycemic control (HbA1c values) into two groups: moderate glycemic control (>7-8% HbA1c, no = 30) and poor glycemic control (>8% HbA1c, no = 50), respectively. Diabetic control parameters, fasting blood sugar (FS), HbA1c, fasting insulin (IF), insulin resistance (IR), HOMA-IR, inflammatory cytokines (IL-6, IL-8, IL-18, IL-23, TNF-α, and CRP), osteopontin, and myokines (adropin and irisin) were estimated by colorimetric and immune ELISA assays, respectively. In addition, real-time RT-PCR analysis was performed to evaluate the expression of circulating miRNAs, miR-146a and miR-144, in the serum of all diabetic subjects.

RESULTS

In this study, T2D patients with poor glycemic control showed a significant increase in the serum levels of IL-6, IL-8, IL-18, IL-23, TNF-α, CRP, and OPN and a reduction in the levels of myokines, adropin and irisin, compared to patients with moderate glycemic control. The results obtained are significantly correlated with the severity of diabetes measured by HbA1c, FS, IF, and HOMA-IR. In addition, baseline expression of miR-146a is significantly reduced and miR-144 is significantly increased in T2D patients with poor glycemic control compared to those with moderate glycemic control. In all diabetic groups, the expression of miR-146a and miR-144 is significantly correlated with diabetic controls, inflammatory cytokines, myokines, and serum levels of OPN. Respective of gender, women with T2D showed more significant change in the expressed miRNAs, inflammatory cytokines, OPN, and serum myokine markers compared to men. ROC analysis identified AUC cutoff values of miR-146a, miR-144, adropin, irisin, and OPN expression levels with considerable specificity and sensitivity which recommends the potential use of adropin, irisin, and OPN as diagnostic biomarkers for diabetes with varying glycemic control status.

CONCLUSION

In this study, molecular expression of certain microRNA species, such as miR-146a and miR-144, was identified and significantly associated with parameters of disease severity, HbA1c, inflammatory cytokines, myokines, and serum osteopontin in T2D patients with moderate and poor glycemic control. The AUC cutoff values of circulating miRNAs, miR-146a and miR-144; myokines, adropin and irisin; and serum OPN were significantly identified by ROC analysis which additionally recommends the potential use of these biomarkers, miR-146a, miR-144, adropin, irisin, and OPN, as diagnostic biomarkers with considerable specificity and sensitivity for diabetes in patients with varying glycemic control status.

Combination of Antioxidant Enzyme Overexpression and N-Acetylcysteine Treatment Enhances the Survival of Bone Marrow Mesenchymal Stromal Cells in Ischemic Limb in Mice With Type 2 Diabetes

Background

Therapy with mesenchymal stem cells remains a promising but challenging approach to critical limb ischemia in diabetes because of the dismal cell survival.

Methods and Results

Critical limb ischemia in type 2 diabetes mouse model was used to explore the impact of diabetic limb ischemia on the survival of bone marrow mesenchymal stromal cells (bMSCs). Inhibition of intracellular reactive oxygen species was achieved with concomitant overexpression of superoxide dismutase (SOD)‐1 and glutathione peroxidase‐1 in the transplanted bMSCs, and extracellular reactive oxygen species was attenuated using SOD‐3 overexpression and N‐acetylcysteine treatment. In vivo optical fluorescence imaging and laser Doppler perfusion imaging were used to track cell retention and determine blood flow in diabetic ischemic limb, respectively. Survival of the transplanted bMSCs was significantly decreased in diabetic ischemic limb compared with the control. In vitro study indicated that advanced glycation end products, not high glucose, significantly decreased the proliferation of bMSCs and increased their apoptosis associated with increased reactive oxygen species production and selective reduction of SOD‐1 and SOD‐3. In vivo study demonstrated that concomitant overexpression of SOD‐1, SOD‐3, and glutathione peroxidase‐1, or host treatment with N‐acetylcysteine, significantly enhanced in vivo survival of transplanted bMSCs, and improved critical limb ischemia in diabetic mice. Combination of triple antioxidant enzyme overexpression in bMSCs with host N‐acetylcysteine treatment further improved bMSC survival with enhanced circulatory and functional recovery from diabetic critical limb ischemia.

Conclusions

Simultaneous suppression of reactive oxygen species from transplanted bMSCs and host tissue could additively enhance bMSC survival in diabetic ischemic limb with increased therapeutic efficacy in diabetes.

Complex Coronary Instent Chronic Total Occlusion Lesions: Oxidative Stress, Inflammation, and Coronary Stent Lengths

The oxidative stress and inflammation played the key roles in the development of atherosclerotic coronary plaques. However, the relationships between pro/antioxidant, pro/anti-inflammatory status, and complex coronary instent chronic total occlusion lesions were not clear in the elderly patients with very long stent implantations. We tried to evaluate the roles of pro/antioxidant and pro/anti-inflammatory biomarkers in the diagnosis of complex reocclusion lesions in elderly patients after coronary stenting. We evaluated the expression levels of acrolein (ACR), malondialdehyde (MDA), high sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α), superoxide dismutase 3 (SOD3), paraoxonase-1 (PON-1), endothelial nitric oxide synthase (eNOS), and stromal cell-derived factor-1α (SDF-1α) in the elderly patients with very long stent implantations and complex reocclusion lesions. Levels of ACR, MDA, hs-CRP, and TNF-α were remarkably increased (P < 0.001), and levels of SOD3, PON-1, eNOS, and SDF-1α were decreased significantly (P < 0.001) in the elderly patients with very long stents and complex reocclusion lesions. The prooxidant and proinflammatory biomarkers were remarkably increased, as well as antioxidant and anti-inflammatory biomarkers were decreased significantly in the elderly patients with very long stent implantations and complex reocclusion lesions after coronary stenting. In conclusion, these findings indicated that the imbalance between prooxidant/proinflammatory and antioxidant/anti-inflammatory status was associated with complex reocclusion lesions, suggesting that oxidative stress and inflammation played the key roles in progression of complex reocclusion lesions in the elderly patients with very long stent implantations.

Efficacy and Safety of Ezetimibe in Combination with Atorvastatin for Acute Coronary Syndrome Patients Accompanied with Type 2 Diabetes: A Single-Center, Non-randomized Cohort Study

Patients with type 2 diabetes (T2DM) and hyperlipidemia are with high risk of myocardial infarction (MI) or coronary death events. The combined use of ezetimibe and atorvastatin could improve treatment efficacy and safety. To explore the efficacy and safety of ezetimibe in combination with atorvastatin for the treatment of patients with T2DM and acute coronary syndrome (ACS). This was a non-randomized cohort study of 95 consecutive, treatment-naïve patients with T2DM and ACS treated at the Quanzhou First Hospital of Fujian Province between February 2014 and March 2016. According to the treatment strategy they selected, the patients were categorized into the atorvastatin (n = 46) and atorvastatin + ezetimibe (n = 49) groups. The patients were followed up at 2 weeks and 12 months. The primary endpoints included the incidence of adverse cardiovascular events and changed in blood lipids and high-sensitivity C-reactive protein (hs-CRP). At 12 months, serum total cholesterol (TC), triglycerides, and low-density lipoprotein cholesterol (LDL-C) levels were significantly lower, and high-density lipoprotein cholesterol (HDL-C) levels were significantly higher in the atorvastatin + ezetimibe (EZ) group than in the atorvastatin group (all p < 0.05). The LDL-C control rate at 12 months was significantly higher in the atorvastatin + EZ group compared with the atorvastatin group (p = 0.006). Seven patients in the atorvastatin group were re-hospitalized for angina pectoris, while only one patient in the atorvastatin + EZ group was re-hospitalized for angina pectoris (p = 0.02). The efficacy of atorvastatin + EZ in treating T2DM patients accompanied with ACS was significantly higher than using atorvastatin alone. This combined strategy has good safety profile, and could be recommended for clinical application.

Modulating cell culture oxidative stress reduces protein glycation and acidic charge variant formation

Controlling acidic charge variants is critical for an industrial bioprocess due to the potential impact on therapeutic efficacy and safety. Achieving a consistent charge variant profile at manufacturing scale remains challenging and may require substantial resources to investigate effective control strategies. This is partially due to incomplete understanding of the underlying causes for charge variant formation during the cell culture process. To address this gap, we examined the effects of four process input factors (temperature, iron concentration, feed media age, and antioxidant (rosmarinic acid) concentration) on charge variant profile. These factors were found to affect the charge profile by modulating the cell culture oxidative state. Process conditions with higher acidic peaks corresponded to elevated supernatant peroxide concentration, intracellular reactive oxygen species (ROS) levels, or both. Changes in glycation level were the primary cause of the charge heterogeneity, and for the first time, supernatant peroxide was found to positively correlate with glycation levels. Based on these findings, a novel mathematical model was developed to demonstrate that the rate of acidic species formation was exponentially proportional to the concentrations of supernatant peroxide and protein product. This work provides critical insights into charge variant formation during the cell culture process and highlights the importance of modulating of cell culture oxidative stress for charge variant control.

Increased glycated albumin and decreased esRAGE levels in serum are related to negative coronary artery remodeling in patients with type 2 diabetes: an Intravascular ultrasound study

BACKGROUND

Negative coronary artery remodeling is frequent in patients with diabetes, but its mechanism remains unclear. We here evaluated the association of serum levels of glycated albumin (GA) and endogenous secretory receptor for advanced glycation end products (esRAGE) with coronary artery remodeling in type 2 diabetic patients.

METHODS

Serum levels of GA and esRAGE were measured and intravascular ultrasound was performed in 136 consecutive diabetic patients with 143 coronary intermediate lesions. The remodeling index (RI) was calculated as the ratio between external elastic membrane (EEM) area at the lesion site and EEM area at the reference segment. Negative remodeling (NR) was defined as an RI < 0.95 and intermediate or positive remodeling as an RI ≥ 0.95.

RESULTS

Mean plaque burden at the lesion site was 70.96 ± 9.98%, and RI was 0.96 ± 0.18. Negative coronary arterial remodeling existed in 81 (56.6%) lesions. RI correlated closely with serum esRAGE level (r = 0.236, P = 0.005) and was inversely related to serum GA level (r = - 0.240, P = 0.004) and plasma low-density lipoprotein cholesterol (LDL-C) (r = - 0.206, P = 0.014) and total cholesterol levels (r = - 0.183, P = 0.028). Generalized estimating equations logistic regression analysis identified esRAGE (OR 0.037; 95% CI 0.012-0.564, P = 0.021), GA (OR 1.093; 95% CI 1.013-1.179, P = 0.018) and LDL-C (OR 1.479; 95% CI 1.072-2.835, P = 0.023) as independent predictors for negative remodeling.

CONCLUSIONS

In diabetic patients, negative coronary artery remodeling is associated with increased GA and decreased esRAGE levels in serum.

Glycated Albumin Is a More Useful Glycation Index than HbA1c for Reflecting Renal Tubulopathy in Subjects with Early Diabetic Kidney Disease

BACKGROUND

The aim of this study was to investigate which glycemic parameters better reflect urinary N-acetyl-β-D-glucosaminidase (uNAG) abnormality, a marker for renal tubulopathy, in subjects with type 2 diabetes mellitus (T2DM) subjects with normoalbuminuria and a normal estimated glomerular filtration rate (eGFR).

METHODS

We classified 1,061 participants with T2DM into two groups according to uNAG level-normal vs. high (>5.8 U/g creatinine)-and measured their biochemical parameters.

RESULTS

Subjects with high uNAG level had significantly higher levels of fasting and stimulated glucose, glycated albumin (GA), and glycosylated hemoglobin (HbA1c) and lower levels of homeostasis model assessment of β-cell compared with subjects with normal uNAG level. Multiple linear regression analyses showed that uNAG was significantly associated with GA (standardized β coefficient [β]=0.213, P=0.016), but not with HbA1c (β=?0.137, P=0.096) or stimulated glucose (β=0.095, P=0.140) after adjusting confounding factors. In receiver operating characteristic analysis, the value of the area under the curve (AUC) for renal tubular injury of GA was significantly higher (AUC=0.634; 95% confidence interval [CI], 0.646 to 0.899) than those for HbA1c (AUC=0.598; 95% CI, 0.553 to 0.640), stimulated glucose (AUC=0.594; 95% CI, 0.552 to 0.636), or fasting glucose (AUC=0.558; 95% CI, 0.515 to 0.600). The optimal GA cutoff point for renal tubular damage was 17.55% (sensitivity 59%, specificity 62%).

CONCLUSION

GA is a more useful glycation index than HbA1c for reflecting renal tubulopathy in subjects with T2DM with normoalbuminuria and normal eGFR.

Proteomic and bioinformatic discovery of biomarkers for diabetic nephropathy

Diabetes is associated with numerous metabolic and vascular risk factors that contribute to a high rate of micro-vascular and macro-vascular disorders leading to mortality and morbidity from diabetic complications. In this case, the major cause of death in overall diabetic patients results from diabetic nephropathy (DN) or renal failure. The risk factors and mechanisms that correspond to the development of DN are not fully understood and so far, no specific and sufficient diagnostic biomarkers are currently available other than micro- or macroalbuminuria. Therefore, this review describes current and novel protein biomarkers in the context of DN as well as probable proteins biomarkers associated with pathological processes for the early stage of DN via proteomics data together with bioinformatics. In addition, the mechanisms involved in early development of diabetic vascular disorders and complications resulting from glucose induced oxidative stress will also be explored.

Glycated albumin (GA) and inflammation: role of GA as a potential marker of inflammation

AIMS

Abnormal levels of glycated albumin (GA) are associated with the onset of both diabetes and inflammation. Although inflammation has long been associated with diabetes, this article aims to explore the underlying mechanisms of this relationship as it pertains to the role of GA.

METHODS

We have reviewed 52 research articles since the year 2000. Common search terms used were "(inflammatory mediator) and GA" or "inflammation and GA". The findings have been organized according to diabetic complications with respect to the interactions of GA and inflammatory mediators. Glycated albumin and specific inflammatory mediators have been reported to play various roles in the pathogenesis of insulin resistance, atherosclerosis, coronary artery disease, retinopathy, and nephropathy. In the case of nephropathy and recently retinopathy, there is considerable evidence for GA in concert with inflammation playing a direct role in organ pathology. There is copious literature detailing GA's involvement in stimulating inflammatory markers and certain pro-inflammatory cytokines. A recent clinical study has shown GA to be a marker for inflammation in non-diabetic rheumatoid arthritis patients with the significance of standard inflammatory markers.

CONCLUSIONS

The clinical utility of GA measurement may likely reside in its versatility as both a mediator of inflammation as well as a marker to track hyperglycemia and other diabetes complications. Further understanding of the role GA plays in glycemic and inflammatory diseases could lead to its acceptance as an independent bio-inflammatory marker.

Methods of albumin estimation in clinical biochemistry: Past, present, and future

Estimation of serum and urinary albumin is routinely performed in clinical biochemistry laboratories. In the past, precipitation-based methods were popular for estimation of human serum albumin (HSA). Currently, dye-binding or immunochemical methods are widely practiced. Each of these methods has its limitations. Research endeavors to overcome such limitations are on-going. The current trends in methodological aspects of albumin estimation guiding the field have not been reviewed. Therefore, it is the need of the hour to review several aspects of albumin estimation. The present review focuses on the modern trends of research from a conceptual point of view and gives an overview of recent developments to offer the readers a comprehensive understanding of the subject.

Association of serum high-sensitivity C-reactive protein with metabolic control and diabetic chronic vascular complications in patients with type 2 diabetes

AIMS

To determine an association between hs-CRP and metabolic control/diabetic chronic vascular complications (DCVCCxs) in the patients with type 2 diabetes (DM). In addition, the possibility of using hs-CRP levels to predict risk of DCVCCxs will also be validated.

METHODS

This cohort study randomly enrolled 608 patients with DM during the 2007-2008 study period. We also recorded basic laboratory findings at baseline and at one year, to include fasting plasma glucose, HbA1c, triglyceride, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and hs-CRP.

RESULTS

Logistic regressions of odds ratios between hs-CRP and DCVCCxs (coronary arterial disease, cerebrovascular disease, diabetic nephropathy, diabetic retinopathy, and diabetic peripheral neuropathy) showed significant correlations, except for cerebrovascular disease, as follows 0.2 (0.11-0.38), 0.09 (0.01-0.77), 0.06 (0.02-0.16), 0.31 (0.12-0.82), and 0.17 (0.07-0.43), respectively. Linear regression for changes in hs-CRP were significantly correlated with HbA1c (r=0.38), fasting plasma glucose (r=0.40), triglyceride (r=0.20), low-density lipoprotein cholesterol (r=0.12), and high-density lipoprotein cholesterol (r=-0.12). No correlation was found for total cholesterol (r=0.06). Based on receiver operating characteristic (ROC) analysis, the cut-off points for hs-CRP levels for prediction of DCVCCxs were 2.89, 2.25, 2.10, 2.25, and 2.82mg/L, for coronary arterial disease, cerebrovascular disease, diabetic nephropathy, diabetic retinopathy, and diabetic peripheral neuropathy, respectively.

CONCLUSIONS

Our data showed that DCVCCxs were associated with hs-CRP in patients with DM. The cut-off point for hs-CRP can be used to predict association with DCVCCxs. Well-controlled metabolic components in diabetic patients, especially HbA1c, fasting plasma glucose, and triglyceride may reduce the level of hs-CRP.

Prognostic value of high sensitivity C-reaction protein in non-insulin dependent diabetes mellitus patients with non-alcoholic fatty liver disease

BACKGROUND AND PURPOSE

High sensitivity C-reaction protein (hsCRP) has been used as a significant predictive factor of cardiovascular events in patients with non-insulin dependent diabetes mellitus (NIDDM). However, existing reports in regards to the significance of hsCRP in predicting the progression of hepatic complications in NIDDM patients are too sparse to deliver clear results. This study is aimed at investigating the prognostic value of hsCRP in NIDDM patients with non-alcoholic fatty liver disease (NAFLD).

METHODS

1128 NIDDM patients with a definite diagnosis of NAFLD were enrolled and followed for one year. The baseline body mass index (BMI), waist-hip circumference ratio (WHR), serum aspartate aminotransferase (AST), presence of hypertension, alanine aminotransferase (ALT), serum hsCRP, total cholesterol (Tch), fasting blood glucose (FBG), triglycerine (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and hepatitis B surface antigen (HBsAg) were recorded to analyze the significance of hsCRP in predicting the short-term progression from NAFLD to non-alcoholic steatohepatitis (NASH).

RESULTS

One year after baseline, 32% of the NAFLD patients suffered progression to NASH and the percentages of NASH were respectively 8.2%, 12.5%, 33.8% and 72.6% in 4 groups with quartered baseline serum level of hsCRP; there was significant difference among the 4 groups in percentage of NASH (P<0.001). With sex, age, WHR, BMI, hypertension, TG, TCH, HDL-C, LDL-C, FBG and HBsAg included, the calibrated regression model gave the OR values of 1.000, 1.669, 6.635 and 32.131 in in 4 quartered baseline serum levels of hsCRP.

CONCLUSION

High serum level of hsCRP is an independent risk factor of short-term progression to NASH in patients with NIDDM and NAFLD. Those NIDDM patients with NAFLD that present with high serum level of hsCRP should be subjected to regular monitoring, lifestyle intervention and medication.

Diabetes, diabetic complications, and fracture risk

Diabetes and osteoporosis are both common diseases with increasing prevalences in the aging population. There is increasing evidence corroborating an association between diabetes mellitus and bone. This review will discuss the disease complications of diabetes on the skeleton, highlighting findings from epidemiological, molecular, and imaging studies in animal models and humans. Compared to control subjects, decreased bone mineral density (BMD) has been observed in type 1 diabetes mellitus, while on average, higher BMD has been found in type 2 diabetes; nonetheless, patients with both types of diabetes are seemingly at increased risk of fractures. Conventional diagnostics such as DXA measurements and the current fracture risk assessment tool (FRAX) risk prediction algorithm for estimating risk of osteoporotic fractures are not sufficient in the case of diabetes. A deterioration in bone microarchitecture and an inefficient distribution of bone mass with insufficiency of repair and adaptation mechanisms appear to be factors of relevance. A highly complex and heterogeneous molecular pathophysiology underlies diabetes-related bone disease, involving hormonal, immune, and perhaps genetic pathways. The detrimental effects of chronically elevated glucose levels on bone should be added to the more well-known complications of diabetes.

Increased concentration of C-reactive protein in obese patients with type 2 diabetes is associated with obesity and presence of diabetes but not with macrovascular and microvascular complications or glycemic control

The purpose of this study was to assess the concentration of C-reactive protein (CRP) in obese type 2 diabetes mellitus (DM2) patients and its association with macrovascular and microvascular complications. The study group consisted of 80 obese DM2 patients, including 20 macrovascular, 20 microvascular, 20 both macrovascular and microvascular, and 20 with no complications patients. The control group comprised 40 normoglycemic subjects—20 obese and 20 of normal body weight. Highly sensitive CRP and metabolic control parameters were assessed. CRP levels in obese diabetes subgroups and normoglycemic obese were similar and significantly higher than those in nonobese controls. No correlation was found between CRP and diabetes control parameters. There was a strong positive correlation between CRP level and body mass index in all groups. A multivariate analysis showed that DM2 and obesity are independent factors increasing CRP levels. Increased concentration of CRP in obese DM2 patients is related to obesity and diabetes itself. The lack of association between CRP and vascular complications remains unclear.

Glycemic variability and oxidative stress: a link between diabetes and cardiovascular disease?

Diabetes is associated with a two to three-fold increase in risk of cardiovascular disease. However, intensive glucose-lowering therapy aiming at reducing HbA1c to a near-normal level failed to suppress cardiovascular events in recent randomized controlled trials. HbA1c reflects average glucose level rather than glycemic variability. In in vivo and in vitro studies, glycemic variability has been shown to be associated with greater reactive oxygen species production and vascular damage, compared to chronic hyperglycemia. These findings suggest that management of glycemic variability may reduce cardiovascular disease in patients with diabetes; however, clinical studies have shown conflicting results. This review summarizes the current knowledge on glycemic variability and oxidative stress, and discusses the clinical implications.

Development of an HbA1c-based conversion equation for estimating glycated albumin in a Korean population with a wide range of glucose intolerance

Background

Compared to the golden standard glycation index of HbA1c, glycated albumin (GA) has potentials for assessing insulin secretory dysfunction and glycemic fluctuation as well as predicting diabetic vascular complications. However, the reference ranges of GA and a conversion equation need to be clearly defined. We designed this study to determine the reference ranges in patients with normal glucose tolerance (NGT) based on conventional measures of glycemic status and to devise a conversion equation for calculating HbA1c and GA in a Korean population.

Methodology/Principal Findings

In this multicenter, retrospective, cross-sectional study, we recruited antidiabetic drug-naïve patients with available glycemic variables including HbA1c, GA, and fasting plasma glucose regardless of glucose status. For the reference interval of serum GA, 5^th to 95^th percentile value of GA in subjects with NGT was adopted. The conversion equation between HbA1c and GA was devised using an estimating regression model with unknown break-points method. The reference range for GA was 9.0–14.0% in 2043 subjects. The 95^th percentile responding values for FPG, and HbA1c were approximately 5.49 mmol/l, and 5.6%, respectively. The significant glycemic turning points were 5.868% HbA1c and 12.2% GA. The proposed conversion equation for below and above the turning point were GA (%) = 6.960+0.8963 × HbA1c (%) and GA (%) = −9.609+3.720 × HbA1c (%), respectively.

Conclusions/Significance

These results should be helpful in future studies on the clinical implications of high GA relative to HbA1c and the clinical implementation of diabetes management.

Cross-sectional and longitudinal relationships between perceived stress and C-reactive protein in men and women

To date, an examination of the longitudinal relationship between perceived stress and C-reactive protein (CRP) is limited. We explored the relationship between perceived stress and CRP concurrently and across 2 and 4 years in 383 men and women. Multiple linear regressions examined the cross-sectional and longitudinal relationships between baseline stress and counter-stress scores with CRP at baseline, 2 years after baseline and 4 years after baseline, while controlling for covariates (age, smoking status, anti-inflammatory use, oral contraceptive use, physical activity, menopausal status, years since onset of menopause, post-menopausal hormone use and body mass index). Results indicate that stress and counter-stress were not related to CRP in either men or women at study baseline or 2 years later. Across a 4-year time frame, higher stress values were related to higher CRP values in women, but not men. Counter-stress was not related to CRP values in men or women across the 4 years. This study highlights the importance of examining the cross-sectional and longitudinal relationship between perceived stress and inflammation separately in men and women.

Syzygium cumini is more effective in preventing the increase of erythrocytic ADA activity than phenolic compounds under hyperglycemic conditions in vitro

Syzygium cumini (S. cumini) is a plant known for its antidiabetic properties. The aim of this study was to evaluate the effect of Sc aqueous leaf extract (ASc) on adenosine deaminase (ADA) activity in erythrocytes (RBCs) exposed to high glucose concentrations (30 mM) in vitro. We also investigated the effects of the main phenolic compounds found in ASc (gallic acid, rutin, and chlorogenic acid) and the effects of insulin, caffeine, and dipyridamole, which are substances involved in the adenosine metabolism, on ADA activity in vitro. Blood samples were obtained from healthy volunteers and a suspension of RBCs was used for the determination of ADA activity. The results showed that: (1) the effect of ASc on ADA activity was more significant than the combination of phenolic compounds; (2) insulin, caffeine, or dipyridamole prevented high glucose increase of ADA activity at doses as low as 50 μU/mL, 25 μM, and 1 μM, respectively; (3) the inhibitory effect caused by ASc on erythrocyte ADA activity remained practically the same after the combination of the extract with insulin or caffeine; (4) when RBCs were exposed to ASc plus dipyridamole, this chemical attenuated the effect of ASc on ADA activity, suggesting an antagonism or a competition with ASc by the same site of action. Therefore, ASc was more effective in preventing the increase in ADA activity than phenolic compounds, suggesting that ASc may collaborate to improve endothelial dysfunction, antioxidant, anti-inflammatory, and antithrombotic properties of adenosine by affecting its metabolism. The results of this study help to provide evidence of the empirically supported benefits of the use of S. cumini in diabetes.

Lower beta cell function relates to sustained higher glycated albumin to glycated hemoglobin ratio in Japanese patients with type 2 diabetes

The aim of this study was to clarify the relationship between baseline beta cell function and future glycated albumin (GA) to glycated hemoglobin ratio (GA/HbA1c) in patients with type 2 diabetes. In our retrospective cohort, 210 type 2 diabetic patients who had been admitted to our hospital and in whom HbA1c and GA had been measured at baseline and 2 years after admission were included in this study. Baseline beta cell function was assessed by postprandial C-peptide immunoreactivity index (PCPRI) during admission. With intensification of treatment during admission, HbA1c and GA were significantly decreased 1 year and 2 years after admission. While baseline HbA1c was not significantly correlated with HbA1c after 2 years, baseline GA/HbA1c was strongly correlated with GA/HbA1c after 2 years (r = 0.575, P <0.001). When the patients were divided into two groups according to median PCPRI, patients with low PCPRI showed higher GA/HbA1c both at baseline and after 2 years compared to those with high PCPRI. There was a significant negative correlation between PCPRI and GA/HbA1c after 2 years (r = -0.379, P <0.001). Multiple regression analysis revealed that PCPRI was an independent predictor of GA/HbA1c after 2 years. In conclusion, our findings suggest that lower beta cell function is associated with sustained higher GA/HbA1c ratio in patients with type 2 diabetes.

Association of increased serum glycated albumin levels with low coronary collateralization in type 2 diabetic patients with stable angina and chronic total occlusion

BACKGROUND

We investigated whether serum glycated albumin (GA) levels are related to coronary collateralization in type 2 diabetic patients with chronic total occlusion.

METHODS

Blood levels of GA and glycosylated hemoglobin (HbA1c) were determined in 317 diabetic and 117 non-diabetic patients with stable angina and angiographic total occlusion of at least one major coronary artery. The degree of collaterals supplying the distal aspect of a total occlusion from the contra-lateral vessel was graded as low (Rentrop score of 0 or 1) or high collateralization (Rentrop score of 2 or 3).

RESULTS

For diabetic patients, GA (21.2 ± 6.5% vs. 18.7 ± 5.6%, P < 0.001) but not HbA1c levels (7.0 ± 1.1% vs. 6.8 ± 1.3%, P = 0.27) was significantly elevated in low collateralization than in high collateralization group, and correlated inversely with Rentrop score (Spearmen's r = -0.28, P < 0.001; Spearmen's r = -0.10, P = 0.09, respectively). There was a trend towards a larger area under the curve of GA compared with that of HbA1c for detecting the presence of low collateralization (0.64 vs. 0.58, P = 0.15). In non-diabetic patients, both GA and HbA1c levels did not significantly differ regardless the status of coronary collateralization. In multivariable analysis, female gender, age > 65 years, smoke, non-hypertension, duration of diabetes > 10 years, metabolic syndrome, eGFR < 90 ml/min/1.73 m2, and GA > 18.3% were independently determinants for low collateralization in diabetic patients.

CONCLUSIONS

Increased GA levels in serum are associated with impaired collateral growth in type 2 diabetic patients with stable angina and chronic total occlusion.

Glycated albumin causes pancreatic β-cells dysfunction through autophagy dysfunction

Growing evidence suggests that advanced glycation end-products (AGEs) are cytotoxic to pancreatic β-cells. The aims of this study were to investigate whether glycated albumin (GA), an early precursor of AGEs, would induce dysfunction in pancreatic β-cells and to determine which kinds of cellular mechanisms are activated in GA-induced β-cell apoptosis. Decreased viability and increased apoptosis were induced in INS-1 cells treated with 2.5 mg/mL GA under 16.7mM high-glucose conditions. Insulin content and glucose-stimulated secretion from isolated rat islets were reduced in 2.5 mg/mL GA-treated cells. In response to 2.5 mg/mL GA in INS-1 cells, autophagy induction and flux decreased as assessed by green fluorescent protein-microtubule-associated protein 1 light chain 3 dots, microtubule-associated protein 1 light chain 3-II conversion, and SQSTM1/p62 in the presence and absence of bafilomycin A1. Accumulated SQSTM1/p62 through deficient autophagy activated the nuclear factor-κB (p65)-inducible nitric oxide synthase-caspase-3 cascade, which was restored by treatment with small interfering RNA against p62. Small interfering RNA treatment against autophagy-related protein 5 significantly inhibited the autophagy machinery resulting in a significant increase in iNOS-cleaved caspase-3 expression. Treatment with 500μM 4-phenyl butyric acid significantly alleviated the expression of endoplasmic reticulum stress markers and iNOS in parallel with upregulated autophagy induction. However, in the presence of bafilomycin A1, the decreased viability of INS-1 cells was not recovered. Glycated albumin, an early precursor of AGE, caused pancreatic β-cell death by inhibiting autophagy induction and flux, resulting in nuclear factor-κB (p65)-iNOS-caspase-3 cascade activation as well as by increasing susceptibility to endoplasmic reticulum stress and oxidative stress.

12S-hydroxyeicosatetraenoic acid levels link to coronary artery disease in Type 2 diabetic patients

BACKGROUND

12(S)-Hydroxyeicosatetraenoic acid (12(S)-HETE) is a metabolite of arachidonic acid. 12(S)-HETE is involved in the pathogenesis of atherosclerosis and diabetes. However, the correlation between 12(S)-HETE and coronary artery disease (CAD) in the diabetic patient is unclear.

AIMS

The study investigated the relationship between 12(S)-HETE and CAD in Type 2 diabetes (T2D).

METHODS

Plasma 12(S)- HETE levels were detected by enzyme-linked immunosorbent assay in 103 healthy controls (control), 109 diabetic patients without CAD (diabetic), and 152 diabetic patients with CAD (diabetic-CAD).

RESULTS

12(S)-HETE levels were higher in both diabetic and diabetic-CAD groups compared to control and in the diabetic-CAD group compared to the diabetic group. In the multiple linear stepwise regression analysis, 12(S)-HETE levels correlated independently with CAD, systolic blood pressure, and glycated hemoglobin.

CONCLUSIONS

These results indicate that 12(S)-HETE levels are increased in diabetic patients with CAD, suggesting a role for atherosclerosis in T2D.

Diabetic nephropathy: traditional to proteomic markers

Diabetic nephropathy (DN) is one of the major microvascular complications of diabetes and it is defined as a rise in the urinary albumin excretion (UAE) rate and abnormal renal function. Currently, changes in albuminuria are considered a hallmark of onset or progression of DN. However, some patients with diabetes have advanced renal pathological changes and progressive kidney function decline even if urinary albumin levels are in the normal range, indicating that albuminuria is not the perfect marker for the early detection of DN. The present article provides an overview of the literature reporting some relevant biomarkers that have been found to be associated with DN and that potentially may be used to predict the onset and/or monitor the progression of nephropathy. In particular, biomarkers of renal damage, inflammation, and oxidative stress may be useful tools for detection at an early stage or prediction of DN. Proteomic-based biomarker discovery represents a novel strategy to improve diagnosis, prognosis and treatment of DN; however, proteomics-based approaches are not yet available in most of the clinical chemistry laboratories. The use of a panel with a combination of biomarkers instead of urinary albumin alone seems to be an interesting approach for early detection of DN, including markers of glomerular damage (e.g., albumin), tubular damage (e.g., NAG and KIM-1), inflammation (e.g., TNF-α) and oxidative stress (e.g., 8-OHdG) because these mechanisms contribute to the development and outcomes of this disease.

Serum advanced glycation end-products and receptors as prognostic biomarkers in diabetics undergoing coronary artery stent implantation

BACKGROUND

This study investigated the impact of elevated glycated albumin (GA) and reduced soluble receptor for advanced glycation end-products (sRAGE) and endogenous secretory receptor for advanced glycation end-products (esRAGE) levels in serum on the severity of albuminuria, occurrence of contrast-induced acute kidney injury (CI-AKI) and 1-year clinical outcome in type 2 diabetic patients undergoing sirolimus-eluting stent-based percutaneous coronary intervention.

METHODS

We compared serum levels of GA, sRAGE, esRAGE, and glycosylated hemoglobin (HbA1c), occurrence of CI-AKI, and major adverse cardiac events at 1-year clinical follow-up in 3 groups of type 2 diabetes based on 24-hour urinary albumin excretion: I = normoalbuminuria (< 30 mg; n = 190); II = microalbuminuria (30-300 mg; n = 102); and III = macroalbuminuria (≥ 300 mg; n = 86).

RESULTS

Serum levels of GA and HbA1c increased step-wise from group I to III, and serum levels of sRAGE and esRAGE were decreased in the groups with albuminuria, with the lowest values in those with microalbuminuria. GA (Pearson's r = 0.264; P < 0.001), sRAGE (Pearson's r = -0.210; P < 0.001), esRAGE (Pearson's r = -0.145; P = 0.04), and HbA1c (Pearson's r = 0.214; P < 0.001) correlated significantly with urinary albumin excretion. After adjusting for confounding factors, GA, sRAGE, esRAGE, and albuminuria status remained independently associated with both CI-AKI and 1-year major adverse cardiac events.

CONCLUSIONS

Elevated GA and reduced sRAGE and esRAGE levels in serum are associated with severity of albuminuria and postprocedural CI-AKI, and exert a negative impact on 1-year clinical outcome in patients with type 2 diabetes undergoing percutaneous coronary intervention with sirolimus-eluting stent implantation.

Glycated albumin is superior to hemoglobin A1c for evaluating the presence and severity of coronary artery disease in type 2 diabetic patients

OBJECTIVES

This study aimed to compare the value of serum glycated albumin (GA) level versus glycated hemoglobin A(1c) (HbA(1c)) for evaluating the presence and severity of coronary artery disease (CAD) in patients with type 2 diabetes mellitus (T2DM).

METHODS

Serum GA and blood HbA(1c) levels were measured in 829 consecutive T2DM patients with or without angiographically documented significant CAD (≥70% diameter stenosis).

RESULTS

Serum GA levels were higher in diabetic patients with significant CAD than in those without (20.57 ± 4.23 vs. 19.00 ± 4.48%; p < 0.001), but HbA(1c) was similar in the two groups (7.74 ± 1.34 vs. 7.51 ± 1.37% p > 0.05). Compared to HbA(1c), GA correlated more closely with the sum of significant stenotic lesions (r = 0.275, p < 0.001 and r = 0.092, p = 0.019) and the extent index (r = 0.375, p < 0.001 and r = 0.091, p = 0.019). The area under the curve of GA was larger than that of HbA(1c) for detecting the presence of significant CAD (0.637 vs. 0.568; p = 0.046) and 3-vessel disease (0.620 vs. 0.536; p = 0.039). GA, but not HbA(1c), was independently associated with significant CAD.

CONCLUSIONS

Serum GA level is a better indicator than HbA(1c) for evaluating the presence and severity of CAD and predicting major adverse cardiac events in patients with T2DM.

Lipid and protein oxidation products, antioxidant status and vascular complications in poorly controlled type 2 diabetes

The inter-relationships between glycaemic control, the progression of diabetes-related vascular complications, oxidative/antioxidative status and inflammation, have not been fully understood. We measured malondialdehyde (MDA) and carbonyl residues, C-reactive protein (CRP) and antioxidant systems by means of ferric reducing ability of plasma (FRAP) and superoxide dismutase (SOD) activity, in well controlled and poorly controlled type 2 diabetic patients without complications (NC) and in poorly controlled patients with microvascular (MicroVC) and with both micro- and macrovascular complications (Micro+Macro VC). All poorly controlled diabetic patients showed higher MDA and carbonyl residues compared to well controlled NC, as did those with Micro+Macro VC compared to poorly controlled NC. The higher CRP and SOD activity levels reached significance in Micro VC and Micro+Macro VC groups. FRAP decreased only in poorly controlled NC compared to well controlled NC (p<0.05). Glycated hamemoglobin (HbA1c) levels were positively correlated with MDA (p<0.05) and CRP (p<0.001) and inversely associated with FRAP (p<0.05) and SOD (p=0.06). An increase in MDA or carbonyl residues could be a marker of high risk for complications in patients with poorly controlled diabetes and they should be considered for monitoring the effectiveness of drug treatment.

Impact of elevated serum glycated albumin levels on contrast-induced acute kidney injury in diabetic patients with moderate to severe renal insufficiency undergoing coronary angiography

BACKGROUND

Glycated albumin (GA) has been shown to be a better indicator than glycosylated hemoglobin A1c (HbA1c) in terms of severity of renal impairment in patients with type 2 diabetes mellitus (T2DM). This study aimed to determine whether elevated serum GA levels are associated with an increased risk for contrast-induced acute kidney injury (CI-AKI) and worse clinical outcome in patients with T2DM and at least moderate renal insufficiency (RI) undergoing coronary angiography.

METHODS

Serum levels of fasting blood glucose (FBG), HbA1c and GA were measured in 1030 patients with T2DM and moderate to severe RI (eGFR 15-59 mL/min/1.73 m(2)). CI-AKI was defined as ≥ 25% increase in serum creatinine within 72 h after the procedure. Receiver-operating characteristic curve was constructed to assess the predictive value of GA, HbA1c and FBG for CI-AKI. Multivariable logistic regression model was developed to identify risk factors for CI-AKI, and Kaplan-Meier curve analysis was used to compare the rates of dialysis and major adverse cardiac events (MACE) during one-year follow-up.

RESULTS

The overall rate of CI-AKI was 11.1%. GA was significantly higher in patients with CI-AKI than in those without, and correlated positively with changes of renal function after the procedure. After adjusting for age, sex, left ventricular ejection fraction, multi-vessel disease, type and volume of contrast media, FBG, and HbA1c, GA remained an independent risk factor for CI-AKI. GA ≥ 21% was associated with increased rates of dialysis and MACE during one-year follow-up in patients with or without CI-AKI.

CONCLUSIONS

Increased GA level serves as a valuable risk factor for CI-AKI and indicates poor one-year clinical outcome in patients with T2DM and moderate to severe RI.

[Study of cardiovascular risk factors in Tunisian patients with recent type 2 diabetes]

OBJECTIVE

To study the frequency of silent myocardial ischemia (SMI) in Tunisian patients with recent type 2 diabetes and identify cardiovascular risk factors directly in relation with SMI.

PATIENTS AND METHODS

One hundred and twenty diabetics and sixty healthy people have benefited from blood sampling, electrocardiogram and exercise test.

RESULTS

The frequency of SMI was 21% in diabetics and 3% in healthy people (P=0.01). Obesity and hypertension were higher in diabetics than in healthy people (P=0.001 and P<10(-4)). Using unvaried analysis for risk factors with the presence of SMI in diabetics, we found that age greater than 60 yrs, male sex, sedentary and smoking were significantly correlated with SMI; respectively P=0.004, 0.01, 0.009 and 0.03. The SMI was found in 37% of diabetics with high blood pressure vs 8% in diabetics with normal blood pressure and was correlated with hypertriglyceridemia, hypoHDLemia and microalbuminuria. Patients with SMI had at least two cardiovascular risk factors apart from diabetes among those: age greater or equal to 60 yrs, male sex, smoking, hypertension, dyslipidemia and family history of early coronaropathy. Chronic inflammation and hyperhomocysteinemia were significantly correlated to SMI; OR=4.2 and 3.8. In addition, SMI was found in one diabetic over three who had bad glycemic control. Using multivariate analysis, only age greater or equal to 60 yrs, smoking, hypertension, hyperhomocysteinemia and hypertriglyceridemia were risk factors directly in relation with SMI in type 2 diabetes.

CONCLUSION

The assessment of global cardiovascular risk from the moment of discovering type 2 diabetes and the early screening of SMI should be necessary.

High-sensitivity C-reactive protein: a novel cardiovascular risk predictor in type 2 diabetics with normal lipid profile

BACKGROUND

India is the diabetic capital of the world. Coronary heart disease is a major cause of morbidity and mortality among diabetics. Type 2 diabetes mellitus and atherosclerosis are complex diseases sharing common antecedents like inflammation. High-sensitivity C-reactive protein (hs-CRP), an acute phase reactant protein, is a proinflammatory atherogenic circulating marker which can prove to be an independent cardiac risk predictor.

AIM

The aim of the present study was to evaluate the role of hs-CRP as an independent cardiovascular risk marker among Indians with type 2 diabetes with normal lipid profile.

SETTINGS AND DESIGN

This was a case control study including 60 type 2 diabetics with normal lipid profile and 60 age- and sex-matched healthy controls.

MATERIALS AND METHODS

Twelve-hour fasting blood samples were collected from all the participants. Serum was assayed for hs-CRP and lipid profile.

STATISTICAL ANALYSIS

Results were analyzed by unpaired t test.

RESULTS

We found elevated hs-CRP levels (4.8 ± 0.2, P < .0001) among cases compared to controls (0.9 ± 0.1). According to hs-CRP levels, seven cases were in the low-risk (< 1 mg/l), 32 in the moderate-risk (1-3 mg/l), and 21 in the high-risk (3-10 mg/l) group with mean values of hs-CRP of 0.7 ± 0.2, 1.75 ± 0.7, and 5.8 ± 1.4, respectively. Relative risk was 4.75 with odds ratio of 10.23 (95% confidence interval 8.8-11.23).

CONCLUSION

The study suggests that hs-CRP is an independent cardiac risk predictor even with normal lipid profile and can help measure additional risk. The American Heart Association stated that patients in the intermediate- and high-risk group may benefit from therapeutic lifestyle change and that cardiovascular event may be prevented.

Acute phase reactant dynamics and incidence of microvascular dysfunctions in type 2 diabetes mellitus

BACKGROUND

Acute Phase Reactants (APRs) have a wide range of activities that contribute to host defense. The aim of this report was to evaluate the dynamics and magnitude of these proteins in various microvascular complications in diabetes mellitus (DM). We also sought to assess the predictive values of APRs and other clinical variables for microvascular complications in DM.

METHODS

This was a case control study carried out in 200 Nigerian subjects with type 2 DM and 100 sex and age matched healthy controls. The studied APRs included C-reactive protein, beta 2 microglobulin, fibrinogen and lipoprotein (a).

RESULTS

The mean values of the APRs were significantly higher in type 2 DM compared with the controls and were observed in higher concentrations in those with microvascular complications, except beta 2 microglobulin. Presence of microvascular complications was observed in those with dilated fundus examination (retinopathy), symptom score of 3.0 (neuropathy), urea and creatinine levels above 50mg% and 1.5mg%, respectively, with significant proteinuria (nephropathy). Significant increase in mean ± SEM values of lipoprotein (a) was observed in diabetic retinopathy in comparison with those without complications (25.76 ± 1.13 mg/dl vs. 22.37 ± 0.73 mg/dl, p = 0.005). Elevated C-reactive protein was observed in diabetic neuropathy in comparison with those without complications (11.43 ± 2.33 u/ml vs. 8.30 ± 1.15 u/ml, p = 0.048). Increased beta 2 microglobulin levels were observed in patients with diabetic foot ulcers in comparison with those without complications (3.04 ± 0.51 mg/dl vs. 2.54 ± 0.14 mg/dl, p = 0.049). Circulating levels of Lipoprotein (a) predicted retinopathy in DM with both good and poor long-term glycemic control while duration of DM predicted the occurrence of foot ulcers..

CONCLUSIONS

Increased level of APRs was associated with a number of microvascular complications and may play a role in the pathogenesis.

Erythrocytic enzymes and antioxidant status in people with type 2 diabetes: beneficial effect of Syzygium cumini leaf extract in vitro

The aim of the present study was to investigate the effects of Syzygium cumini leaf extract (ASc), on Adenosine deaminase (ADA) and Acetylcholinesterase (AChE) activities, and also on oxidative stress parameters in erythrocytes hemolysates (RBCs) and erythrocytes membranes (ghosts) from type 2 diabetics patients (Type 2 DM) under in vitro conditions. Non protein thiol groups (NP-SH), AChE, Catalase (CAT) and Superoxide Dismutase (SOD) activities were measure in RBCs. Further, ADA activity, Thiobarbituric Acid-Reactive Substances (TBARS) levels and protein thiol groups (P-SH) were estimated in ghosts. Also, P-SH and Vitamin C (VIT C) were measure in plasma sample. The results demonstrated that ADA and AChE activities, besides TBARS levels were higher in erythrocytes of Type 2 DM, while SOD activity and NP-SH levels were decreased when compared to control group. ASc, in vitro, reduced ADA and AChE activities and some parameters of oxidative stress. Furthermore, we observed correlations between VIT C and P-SH levels, ADA activity and P-SH levels, as well as NP-SH and TBARS levels in diabetics. The results suggest that ASc in vitro is able to promote the reduction of inflammation and oxidative stress parameters, and act against biochemical changes occurring in Diabetes mellitus (DM).

Serum uric acid level and its association with metabolic syndrome and carotid atherosclerosis in patients with type 2 diabetes

Objective

We aimed to investigate whether elevated serum uric acid concentrations are associated with higher risk of metabolic syndrome (MetS) and carotid atherosclerosis in patients with type 2 diabetes.

Methods

We conducted a population-based cross-sectional survey in Shanghai, with a total of 395 men and 631 women age 41 to 92 years. The carotid artery intima-media thickness (IMT) and carotid atherosclerotic plaques (PLQ) were measured by B-mode ultrasound. MetS was defined according to the updated National Cholesterol Education Program Adult Treatment Panel III criteria for Asian Americans.

Results

Uric acid levels were negatively associated with duration of diabetes, fasting plasma glucose, glycohemoglobin, eGFR, HDL-cholesterol (all P < 0.001) and positively with BMI, CRP, waist circumference, triglycerides, systolic blood pressure, ACR, HOMA-IR and IMT (all P < 0.05). In the highest quartile of uric acid levels, the risks were substantially higher for MetS [odds ratio 3.97, (95% confidence interval 2.58-6.13)] (P < 0.001 for trend) and PLQ [odds ratio 2.71 (95% confidence interval 1.62-4.47)] (p = 0.013 for trend) compared with that in the lowest quartile of uric acid levels after multiple adjustment. These associations remained significant after further adjustment for potential confounders.

Conclusions

Serum uric acid level is associated with MetS and is an independent risk factor for carotid atherosclerosis in patients with type 2 diabetes.

Cardiovascular comorbidities of type 2 diabetes mellitus: defining the potential of glucagonlike peptide-1-based therapies

The global epidemic of diabetes mellitus (~95% type 2 diabetes) has been fueled by a parallel increase in obesity and overweight. Together, these metabolic disease epidemics have contributed to the increasing incidence and prevalence of cardiovascular disease. The accumulation of metabolic and cardiovascular risk factors in patients with type 2 diabetes--risk factors that may exacerbate one another--complicates treatment. Inadequate treatment, treatment that fails to achieve goals, increases the risk for cardiovascular morbidity and mortality. From a clinical perspective, type 2 diabetes is a cardiovascular disease, an observation that is supported by a range of epidemiologic, postmortem, and cardiovascular imaging studies. Vascular wall dysfunction, and particularly endothelial dysfunction, has been posited as a "common soil" linking dysglycemic and cardiovascular diseases. Vascular wall dysfunction promoted by environmental triggers (e.g., sedentary lifestyle) and metabolic triggers (chronic hyperglycemia, obesity) has been associated with the upregulation of reactive oxygen species and chronic inflammatory and hypercoagulable states, and as such with the pathogenesis of type 2 diabetes, atherosclerosis, and cardiovascular disease. Glucagon-like peptide-1 (GLP)-1, an incretin hormone, and synthetic GLP-1 receptor agonists represent promising new areas of research and therapeutics in the struggle not only against type 2 diabetes but also against the cardiovascular morbidity and mortality associated with type 2 diabetes. In a number of small trials in humans, as well as in preclinical and in vitro studies, both native GLP-1 and GLP-1 receptor agonists have demonstrated positive effects on a range of cardiovascular disease pathologies and clinical targets, including such markers of vascular inflammation as high-sensitivity C-reactive protein, plasminogen activator inhibitor-1, and brain natriuretic peptide. Reductions in markers of dyslipidemia such as elevated levels of triglycerides and free fatty acids have also been observed, as have cardioprotective functions. Larger trials of longer duration will be required to confirm preliminary findings. In large human trials, GLP-1 receptor agonists have been associated with significant reductions in both blood pressure and weight.

Antidiabetic effect of glucosaminic acid-cobalt (II) chelate in streptozotocin-induced diabetes in mice

BACKGROUND

The purpose of this study was to assess the in vivo ability of glucosaminic acid-cobalt (II) chelate to reduce glycemia.

METHODS

Different concentrations of chelate solution were administrated to mice with diabetes induced by streptozotocin.

RESULTS

Daily oral administration of chelate solution 0.4 mL at various concentrations (0.32-0.4 g/mL) led to reduction in water intake by the diabetic mice after 5 days of treatment, with a subsequent reduction in glucose levels observed 2 weeks later. Daily food intake was related to both chelate concentration as well as glycemia reduction. The food intake of mice treated with glucosaminic acid-cobalt (II) chelate solution was 1.5-fold that of untreated mice.

CONCLUSION

Glucosaminic acid-cobalt chelate was effective as an antidiabetes agent; its efficacy was proportional to treatment period .The chelated form expressed much less toxicity compared to cobalt only, and stimulated subsequent food intake after daily administration.

Plasma concentrations of osteopontin, but not thrombin-cleaved osteopontin, are associated with the presence and severity of nephropathy and coronary artery disease in patients with type 2 diabetes mellitus

Background

The aim of the present cross-sectional study was to assess possible associations between osteopontin (OPN), and thrombin-cleaved (N-half) OPN, and nephropathy and coronary artery disease (CAD) in patients with type 2 diabetes mellitus (T2DM).

Methods

Plasma levels of OPN, N-half OPN, and high-sensitivity C-reactive protein (hsCRP) were determined in 301 diabetic patients with (n = 226) or without (n = 75) angiographically documented CAD (luminal diameter narrowing >50%), as well as in 75 non-diabetic controls with normal angiography. The estimated glomerular filtration rate (eGFR) was calculated in all patients.

Results

Plasma levels of OPN and hsCRP were significantly higher in patients with T2DM compared with controls. In addition, there was a higher occurrence of moderate renal insufficiency and lower eGFR in patients with T2DM (all P < 0.01). T2DM patients in whom OPN levels were greater than the median value had higher serum creatinine levels, a greater prevalence of mild or moderate renal insufficiency, a higher incidence of CAD, and lower eGFR (all P < 0.05) than T2DM patients in whom OPN levels were the same as or lower than the median value. However, there were no differences in these parameters when patients were stratified according to plasma N-half OPN levels. Furthermore, there was a significant correlation between OPN, but not N-half OPN, and the severity of nephropathy and CAD in diabetes. After adjustment for potential confounders and treatments, multiple linear regression analysis demonstrated an independent association between OPN, but not N-half OPN, and eGFR. Multivariate logistic regression revealed that higher OPN levels conferred a fourfold greater risk of renal insufficiency and CAD in patients with T2DM.

Conclusions

The results of the present study demonstrate that there is an independent association between plasma levels of OPN, but not N-half OPN, and the presence and severity of nephropathy and CAD in diabetes.

Advanced glycation end products induce chemokine/cytokine production via activation of p38 pathway and inhibit proliferation and migration of bone marrow mesenchymal stem cells

Background

Advanced glycation products (AGEs), as endogenous inflammatory mediator, compromise the physiological function of mesenchymal stem cells (MSCs). MSCs have a potential role in cell replacement therapy in acute myocardial infarction and ischemic cardiomyopathy. However, mechanisms of AGEs on MSCs are still not unveiled.

Methods

Reactive oxygen species (ROS), genes regulation, cell proliferation and migration have been detected by AGE-BSA stimulated MSCs.

Results

We found that in vitro stimulation with AGE-BSA induced generation of reactive oxygen species (ROS), and inhibited dose-dependently proliferation and migration of MSCs. Microarray and molecular biological assessment displayed an increased expression and secretion of Ccl2, Ccl3, Ccl4 and Il1b in a dose- and time-dependent manner. These chemokines/cytokines of equivalent concentration to those in conditioned medium exerted an inhibitory effect on MSC proliferation and migration after stimulation for 24 h. Transient elevation of phospho-p38 in MSCs upon AGE-BSA stimulation was blocked with p38 inhibitor.

Conclusions

The study indicates that AGE-BSA induces production of chemokines/cytokines in a dose- and time-dependent manner via activation of ROS-p38 mediated pathway. These chemokines/cytokines exert an inhibitory effect on MSC growth and migration, suggesting an amplified dysfunction of MSCs by AGEs.

Diabetes and inflammation: fundamental aspects and clinical implications

AIM

The aim of this paper is to provide the fundamental background of the inflammation theory associated with type 2 diabetes, to discuss the clinical consequences of low-grade inflammation, particularly in terms of cardiovascular risk, and to infer some clinical therapeutic strategies deriving from drugs that already exist or are in development.

METHODS

This non-exhaustive work is the result of a Pubmed(®) research, based on requests including the following keywords: diabetes, inflammation, innate immunity, obesity, reticulum endoplasmic stress, cytokines, endothelial dysfunction.

RESULTS

Obesity and type 2 diabetes are linked with a low-grade inflammation state that reflects the activation of innate immunity where metabolic, environmental and genetic factors are implicated. The role of endoplasmic reticulum stress and unfold protein response is underlined. Inflammation markers are predictive for the risk to develop diabetes, and are associated with an increased cardiovascular risk. While lifestyle modifications are followed by an improvement in inflammation markers, treatments inferred from the inflammation theory are of great interest, although quite moderate effects on glycaemic control have been observed with some of them.

CONCLUSION

The development of molecules targeting different inflammatory mechanisms could lead in diabetic patients to improvement of both glycaemia and cardiovascular prognosis.

Chromosome 9p21.3 polymorphism in a Chinese Han population is associated with angiographic coronary plaque progression in non-diabetic but not in type 2 diabetic patients

BACKGROUND

We sought to explore the association of variant rs1333049 on chromosome 9p21.3 with coronary artery disease (CAD) and angiographic plaque progression in non-diabetic and type 2 diabetic patients.

METHODS

Genotyping and quantitative coronary angiography (QCA) were performed in 2046 Chinese Han patients (1012 diabetic cases) undergoing coronary angiography; 430 of them received repeat angiographic studies at 1-year follow-up.

RESULTS

CC genotype at rs1333049 on chromosome 9p21.3 was associated with CAD (unadjusted OR 1.524, p = 0.001 and adjusted OR 1.859, p = 0.005, respectively). However, CC genotype had no magnified association with CAD in diabetic patients (OR 1.275, p = 0.150) compared with non-diabetic counterparts (OR 1.446, p = 0.020) after adjusting for conventional risk factors. During angiographic follow-up, non-diabetic patients (n = 280) had significant decrease in minimal lumen diameter and increase in percent diameter stenosis among the three genotypes (p = 0.005 and p = 0.038, respectively), demonstrating that CC or GC genotype carriers had a more severe plaque progression than GG genotype carriers. In patients with type 2 diabetes (n = 150), although plaque progression was more severe than that in non-diabetic counterparts, no relations existed between plaque progression and genotypes. Rs1333049 was an independent determinant of plaque progression for non-diabetic (OR 3.468, p = 0.004 and OR 4.339, p = 0.002 for GC and CC genotype, respectively) but not for diabetic patients (OR 0.529, p = 0.077 and 0R 0.878, p = 0.644 for GC and CC genotype, respectively).

CONCLUSIONS

This study demonstrates a significant association of homozygous CC genotype of rs1333049 on chromosome 9p21.3 with CAD in Chinese Han population. Rs1333049 polymorphism is an independent determinant for coronary plaque progression in non-diabetic but not in type 2 diabetic patients.

Lipoprotein (a), C-reactive protein and some metabolic cardiovascular risk factors in type 2 DM

BACKGROUND

Lipoprotein (a) (LP (a) is an independent cardiovascular risk factor that is not widely studied in people of sub-Saharan African origin. The aim of this report is to determine the frequency of occurrence of elevated Lp (a) and possible relationship with total cholesterol (TCHOL), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides (TG), C reactive protein (CRP) and serum uric acid (SUA).

METHODS

This is a cross sectional study carried out in 200 Nigerian patients with type 2 DM and 100 sex and age matched healthy Controls aged between 32-86 years. We determined the frequency of occurrence of elevated Lp (a) levels in the study subjects and compared clinical and biochemical variables between type 2 diabetic patients and non-diabetic patients. Clinical and biochemical parameters were also compared between subjects with type 2 DM who had elevated LP (a) and normal LP (a) levels. Long term glycaemic control using glycosylated haemoglobin was determined and compared in the study subjects. Test statistics used include chi square, correlation coefficient analysis and Student's t test.

RESULTS

The mean Lp(a) concentration differed significantly between type 2 diabetic patients and the Control subjects (18.7 (5.8) mg/dl vs 23 (6.8) mg/dl, 0.00001). Similarly, the prevalence of high LP (a) levels in type 2 DM patients was significantly higher than that of the Control subjects (12.5% vs 4%, p-0.019). The mean levels of the lipid profile parameters (TCHOL, LDL-C, TG, LDL/HDL) and CRP were significantly higher in DM patients than in the Control subjects. The mean LP (a) levels were comparable in both sexes and in DM subjects with and without hypertension. TG was the only parameter that differed significantly between subjects with elevated Lp (a) levels and those with normal Lp (a) levels. There was a significant positive correlation (r) between Lp(a) levels and TG, LDL-C. TCHOL, LDL/HDL and uric acid. No association was found between Lp(a) and clinical parameters such as age and anthropometric indices.

CONCLUSION

We have showed that Lp (a), CRP and other CVS risk factors cluster more in patients with DM than non DM patients. Serum Lp (a) levels are not associated with anthropometric and glycaemic indices.

Lipoprotein-associated phospholipase A2, C-reactive protein, and coronary artery disease in individuals with type 1 diabetes and macroalbuminuria

Given the paucity of data in type 1 diabetes concerning lipoprotein-associated phospholipase A( 2) (Lp-PLA(2)), we examined its prospective relationship with coronary artery disease (CAD), as well as the effect of modification by C-reactive protein (CRP) and haptoglobin genotype, in individuals with type 1 diabetes who are at an increased risk for CAD due to also having macroalbuminuria (n=96). Although Lp-PLA(2) activity was univariately predictive of CAD (HR=1.54 per SD, p=0.009), this relationship was not significant after covariate adjustment (p=0.59). There was a significant interaction between Lp-PLA(2) and CRP (p=0.02), i.e. those with both markers greater than the median level were more likely to have a CAD event than those persons with low levels of both (HR=2.89, p=0.06). When stratified by haptoglobin genotype, Lp-PLA(2) was predictive of CAD in persons with the 2/1 (HR=2.40, p=0.05), but not 2/2 (HR=0.66, p=0.27), genotype. The association between Lp-PLA(2) activity and CAD differs by CRP and haptoglobin genotype in this group of persons with type 1 diabetes and macroalbuminuria.