Microinflammation is a common risk factor for progression of nephropathy and atherosclerosis in Japanese patients with type 2 diabetes

METTL3/YTHDF2 m6A axis mediates the progression of diabetic nephropathy through epigenetically suppressing PINK1 and mitophagy

AIMS

This research aimed to investigate the specific mechanism of methyltransferase like 3 (METTL3) in the progression of diabetic kidney disease (DKD).

MATERIALS AND METHODS

The model of diabetic kidney disease was established with HK-2 cells and mice in vitro and in vivo. The N6 methyladenosine (m6A) contents in the cells and tissues were detected with a commercial kit and the m6A levels of PTEN induced putative kinase 1 (PINK2) were detected with a MeRIP kit. The mRNA and protein levels were determined with RT-qPCR and western blot. The ROS, TNF-α, and IL-6 levels were assessed with ELISA. The cell proliferative ability was measured by a CCK-8 assay and cell apoptosis was determined with TUNEL staining. The HE and Masson staining was performed to observe the renal morphology. The RIP assay was conducted to detect the interaction between METTL3/YTHDF2 and PINK1.

RESULTS

The m6A content and METTL3 levels were prominently elevated in diabetic kidney disease. METTL3 silencing promoted the cell growth and the expression of LC3 II, PINK1, and Parkin, while inhibiting the cell apoptosis and the expression of LC3 I and p62 in the high glucose (HG) stimulated HK-2 cells. METTL3 silencing also decreased the ROS, TNF-α, and IL-6 levels in diabetic kidney disease. PINK1 silencing neutralized the function of sh-METTL3 in the HG stimulated HK-2 cells. The HE and Masson staining showed that METTL3 silencing alleviated the kidney injury induced by DKD. METTL3 silencing decreased the m6A levels of PINK1, while increased the mRNA levels of PINK1 which depended on YTHDF2.

CONCLUSIONS

METTL3 silencing could inhibit the progression of diabetic nephropathy in vivo and in vitro by regulating the m6A modification of PINK1, which depends on YTHDF2. Our research lays the theoretical foundation for the precise treatment of diabetic kidney disease and the development of targeted drugs in the future.

Effects of glycation end-products on the dental pulp in patients with type 2 diabetes

AIM

This ex vivo study aimed to compare protein expression of advanced glycation end-products (AGE) and receptor (RAGE), and the levels of selected genes associated with inflammation and collagen within dental pulp tissue from patients with type 2 (T2D) diabetes and non-T2D.

METHODOLOGY

Noncarious extracted permanent molar teeth from patients with well-controlled T2D (n = 19) and non-T2D (controls) (n = 19) were collected and compared. The coronal pulp was examined using immunohistochemistry (IHC) (n = 10 per group) for anti-AGE and anti-RAGE. Quantitative PCR (n = 9 per group) was used to analyse the gene expression levels of NFKB, S100A12 and COLIA1. Data analyses were performed between the groups using GraphPad Prism using Pearson correlation, Shapiro-Wilk and Mann-Whitney U-tests, and multiple regression using SPSS.

RESULTS

AGEs were distributed diffusely throughout the pulp extracellular matrix associated with collagen fibres and were present on several cell types. RAGE was expressed at the pulp-dentine interface and was observed on odontoblasts, immune cells, endothelial cells and fibroblasts. Semi-quantitative analysis of IHC samples showed significantly increased expression of AGE (p < .0001) and RAGE (p = .02) in T2D samples compared with controls. The expression of NFKB (p < .0001), S100A12 (p < .0001) and COLIA1 (p = .01) genes were significantly higher in the T2D pulp, and multivariate logistic regression analysis showed that these findings were not affected by age.

CONCLUSION

T2D may exert a similar glycation response in the dental pulp to other body sites. This could occur through activation of NF-κB pathways with a concomitant increase in genes associated with inflammation and collagen.

Suramin prevents the development of diabetic kidney disease by inhibiting NLRP3 inflammasome activation in KK-Ay mice

AIMS/INTRODUCTION

Nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasomes produce IL-18 upon being activated by various stimuli via the P2 receptors. Previously, we showed that serum and urine IL-18 levels are positively associated with albuminuria in patients with type 2 diabetes, indicating the involvement of inflammasome activation in the pathogenesis of diabetic kidney disease (DKD). In the present study, we investigated whether the administration of suramin, a nonselective antagonist of the P2 receptors, protects diabetic KK.Cg-A^y /TaJcl (KK-Ay) mice against DKD progression.

MATERIALS AND METHODS

Suramin or saline was administered i.p. to KK-Ay and C57BL/6J mice once every 2 weeks for a period of 8 weeks. Mouse mesangial cells (MMCs) were stimulated with ATP in the presence or absence of suramin.

RESULTS

Suramin treatment significantly suppressed the increase in the urinary albumin-to-creatinine ratio, glomerular hypertrophy, mesangial matrix expansion, and glomerular fibrosis in KK-Ay mice. Suramin also suppressed the upregulation of NLRP3 inflammasome-related genes and proteins in the renal cortex of KK-Ay mice. P2X4 and P2X7 receptors were significantly upregulated in the isolated glomeruli of KK-Ay mice and mainly distributed in the glomerular mesangial cells of KK-Ay mice. Although neither ATP nor suramin affected NLRP3 expression in MMCs, suramin inhibited ATP-induced NLRP3 complex formation and the downstream expression of caspase-1 and IL-18 in MMCs.

CONCLUSIONS

These results suggest that the NLRP3 inflammasome is activated in a diabetic kidney and that inhibition of the NLRP3 inflammasome with suramin protects against the progression of early stage DKD.

A randomized controlled clinical trial study protocol of Liuwei Dihuang pills in the adjuvant treatment of diabetic kidney disease

INTRODUCTION

A large number of patients with diabetic kidney disease (DKD) approach traditional Chinese medicine (TCM) owing to discontent with standard treatments. Based on TCM theory and clinical experience, the syndrome of kidney yin deficiency is a common type of DKD. Liuwei Dihuang pills (LDPs) is a common prescription of a Chinese herbal formula for patients presenting this syndrome of DKD. However, well-established data supporting the efficacy and safety of LDP in DKD treatment are lacking.

METHODS

We have designed a double-blind, placebo-controlled, randomized trial. After a 2-week run-in period, 124 eligible participants with DKD will be assigned to either the experimental or the control group in a 1:1 ratio. Patients in the experimental group will receive LDP, while patients in the control group will receive a matched placebo. As the basic treatment in the 2 groups, metformin hydrochloride sustained-release tablets, for blood glucose control, and irbesartan tablets, for blood pressure regulation, will be provided. All participants will undergo 4 weeks of treatment and 12 weeks of follow-up. The primary outcome is the change in 24 hours urinary protein levels, measured from the baseline to the end of the treatment phase (week 24). The secondary outcomes to be assessed include the change in serum creatinine and estimated glomerular filtration rate, urinary albumin excretion rate, improvement of TCM syndromes and symptoms, fasting blood glucose and postprandial 2-hour blood glucose, blood lipids (total cholesterol, triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol, from baseline to weeks 12 and 24.

DISCUSSION

The results of this study will provide high-quality evidence of the effects of LDP in DKD treatment, which will provide an alternative treatment strategy in patients with DKD.

Therapeutic effects of interleukin-1 receptor-associated kinase 4 inhibitor AS2444697 on diabetic nephropathy in type 2 diabetic mice

Renal inflammation is a final common pathway of chronic kidney disease including diabetic nephropathy, which is the leading cause of end-stage renal disease and is associated with high cardiovascular risk and significant morbidity and mortality. Interleukin-1 (IL-1) receptor-associated kinase 4 (IRAK-4) is a pivotal molecule for IL-1 receptor- and Toll-like receptor-induced activation of proinflammatory mediators. In this study, we investigated the renoprotective properties of IRAK-4 inhibitor AS2444697 in KK/Ay type 2 diabetic mice. Four-week repeated administration of AS2444697 dose-dependently and significantly improved albuminuria; hyperfiltration, as measured by creatinine clearance; renal injury, including glomerulosclerosis; tubular injury markers, including urinary N-acetyl-β-D-glucosaminidase activity; and glomerular podocyte injury markers, including urinary nephrin excretion. In addition, AS2444697 attenuated plasma levels of proinflammatory cytokines, including IL-6; plasma levels of endothelial dysfunction markers, including intercellular adhesion molecule-1; and plasma levels and renal contents of oxidative stress markers. In contrast, AS2444697 did not significantly affect food intake or blood glucose levels. These results suggest that AS2444697 attenuates the progression of diabetic nephropathy mainly via anti-inflammatory mechanisms through inhibition of IRAK-4 activity under diabetic conditions and may represent a promising therapeutic option for the treatment of type 2 diabetic nephropathy.

Antioxidant, Anti-Inflammatory, and Metabolic Properties of Tocopherols and Tocotrienols: Clinical Implications for Vitamin E Supplementation in Diabetic Kidney Disease

Diabetes mellitus is a metabolic disorder characterized by the development of vascular complications associated with high morbidity and mortality and the consequent relevant costs for the public health systems. Diabetic kidney disease is one of these complications that represent the main cause of end-stage renal disease in Western countries. Hyperglycemia, inflammation, and oxidative stress contribute to its physiopathology, and several investigations have been performed to evaluate the role of antioxidant supplementation as a complementary approach for the prevention and control of diabetes and associated disturbances. Vitamin E compounds, including different types of tocopherols and tocotrienols, have been considered as a treatment to tackle major cardiovascular outcomes in diabetic subjects, but often with conflicting or even negative results. However, their effects on diabetic nephropathy are even less clear, despite several intervention studies that showed the improvement of renal parameters after supplementation in patients with diabetic kidney disease. Then we performed a review of the literature about the role of vitamin E supplementation on diabetic nephropathy, also describing the underlying antioxidant, anti-inflammatory, and metabolic mechanisms to evaluate the possible use of tocopherols and tocotrienols in clinical practice.

Racial and ethnic disparities in predictors of glycemia: a moderated mediation analysis of inflammation-related predictors of diabetes in the NHANES 2007-2010

BACKGROUND/OBJECTIVE

Racial/ethnic disparities in type 2 diabetes (T2D) outcomes exist, and could be explained by nutrition- and inflammation-related differences. The objective of this study is to identify associations between race/ethnicity and glucose control among participants from NHANES 2007-2010, as influenced by diet quality, body mass, and inflammation and grouped by T2D status.

SUBJECTS/METHODS

The following is a cross-sectional, secondary data analysis of two NHANES data cycles spanning 2007-2010. The association between race/ethnicity and hemoglobin A1c (HbA1c) as mediated by dietary intake score, body mass index (BMI), and C-reactive protein (CRP) was assessed, as was the strength of the difference of that association, or moderation, by T2D status. The sample included n = 7850 non-pregnant adult participants ≥ 20 years of age who had two days of reliable dietary recall data, and no missing data on key variables included in the analysis. The primary outcome examined was HbA1c.

RESULTS

The model accurately explained the variation in HbA1c measures in participants without T2D, as mediated by diet quality, BMI, and CRP. However, significant variation in HbA1c remained after accounting for aforementioned mediators when contrasting non-Hispanic White to non-Hispanic Black participants without T2D. The model was not a good fit for explaining racial/ethnic disparities in HbA1c in participants with T2D. A test of the index of moderated mediation for this model was not significant for the differences in the effect of race/ethnicity on HbA1c by T2D status (moderator).

CONCLUSIONS

This study demonstrated that diet quality, BMI, and CRP mediated the effect of race/ethnicity on HbA1c in persons without T2D, but not in persons with T2D. Further research should include additional inflammatory markers, and other inflammation- and T2D-related health outcomes, and their association with racial/ethnic disparities in diabetes.

Weight loss program is associated with decrease α-tocopherol status in obese adults

BACKGROUND & AIMS

Studies on changes in plasma α-tocopherol levels during body fat reduction in obese persons are not clear. The aim of the present study was to assess factors associated with α-tocopherol status in obese people and to examine changes in α-tocopherol status after a 6-week AntioxObesity weight loss program.

METHODS

The study was conducted in 60 overweight or obese adults, aged 18-54 years old. Food intake data were collected using the 3-day record method and a semi-quantitative food-frequency questionnaire. Anthropometric measurements included: height (H), body weight, waist circumference (WC) and hip circumference (HC), body composition: fat mass (FM) and fat-free mass (FFM), subcutaneous fat (SF) and visceral fat (VF). Lipid profile, α-tocopherol concentration, glutathione peroxidase (GPx) activity, total antioxidant capacity (TAC) in plasma and superoxide dismutase (SOD) activity in erythrocytes were determined.

RESULTS

Energy, fat, and carbohydrate intakes decreased significantly in all subjects (P < 0.001). Body weight, WC, body mass index (BMI), waist-to height ratio (WHtR), and FM, VF and SF decreased significantly during the 6 weeks in all subjects. Plasma α-tocopherol significantly decreased during the program (P = 0.006). No changes were observed for SOD activity, but GPx activity and TAC decreased significantly (P = 0.001; P = 0,023, respectively). Plasma α-tocopherol concentration after 6 weeks of the AntioxObesity program was strongly associated with baseline plasma α-tocopherol, changes in TC, VF and FM. Low α-tocopherol status (<20 μmol/L) was found in 78% of the women and 68% of the men, after 6 weeks of the AntioxObesity program. Men were characterized by a greater decrease in weight, BMI, WC, FM, VF, SF and TAC compared to women.

CONCLUSIONS

A 6-week weight loss program lowered α-tocopherol status in overweight and obese people. Low baseline α-tocopherol status and adiposity in obese adults negatively affected α-tocopherol status after 6 weeks weight loss program. These results, coupled with excessive weight and low α-tocopherol intake, led to the finding that there was an increased risk of oxidative stress diseases in adults on a reduced diet. Long-term dietary restriction program for obese patients should be monitored to avoid α-tocopherol deficiency, and take into account higher dietary α-tocopherol requirements for obese people.

Association Between Estimated Glomerular Filtration Rate and Microvascular Complications in Type II Diabetes Mellitus Patients: A 1-Year Cross-Sectional Study

BACKGROUND

Previous studies have indicated that reduced estimated glomerular filtration rate (eGFR) is not only the predictor of renal function impairment in patients with diabetic nephropathy, but also in patients with diabetic neuropathy, diabetic retinopathy, and other diabetic-related complications. Therefore, evaluation of eGFR is critical in diabetic patients. However, there is a paucity of data regarding the association of various stages of kidney disease with microvascular complications.

OBJECTIVE

The objective of the study was to evaluate the association between eGFR and microvascular complications in type II diabetes mellitus (DM) patients.

METHODS

The present 1-year cross-sectional study involved a total of 50 type II DM patients with duration of >5 years. Descriptive data, detailed history regarding the duration of DM, and clinical investigations were performed according to a predesigned and pretested proforma. Specific investigations such as urine microalbumin excretion test and serum creatinine test were also performed. Serum creatinine test was done to calculate the eGFR by modification of diet in renal disease (MDRD) formula. All the type II DM patients were divided into various stages of kidney disease by calculating the eGFR by MDRD. Chi-square test was used to find the association of eGFR with microvascular complications. P < 0.05 was considered statistically significant.

RESULTS

The mean age of the study patients was 57.76 ± 10.35 years with a male predominance. Most of the patients were identified with diabetic nephropathy (33) and diabetic neuropathy (32). Many (21) patients were in stage I kidney disease. Reduced eGFR was associated significantly with diabetic neuropathy (P = 0.007) and diabetic nephropathy (P = 0.0092); whereas, no significant association was observed with diabetic retinopathy (P = 0.285). Furthermore, reduced eGFR led to reduction in glycated hemoglobin levels, and increased the risk of hypertension (P = 0.0401) in patients with type II DM.

CONCLUSION

Overall, eGFR can be considered as a rational noninvasive mode of assessing the renal status in patients with type II DM. Reduction in eGFR is significantly associated with microvascular complications, such as diabetic neuropathy and diabetic nephropathy.

Association between Diastolic Dysfunction with Inflammation and Oxidative Stress in Females ob/ob Mice

Objective: To evaluate autonomic and cardiovascular function, as well as inflammatory and oxidative stress markers in ob/ob female mice.

Methods: Metabolic parameters, cardiac function, arterial pressure (AP), autonomic, hormonal, inflammatory, and oxidative stress markers were evaluated in 12-weeks female wild-type (WT group) and ob/ob mice (OB group).

Results: OB animals showed increased body weight, blood glucose, and triglyceride levels, along with glucose intolerance, when compared to WT animals. Ejection fraction (EF) and AP were similar between groups; however, the OB group presented diastolic dysfunction, as well as an impairment on myocardial performance index. Moreover, the OB group exhibited important autonomic dysfunction and baroreflex sensitivity impairment, when compared to WT group. OB group showed increased Angiotensin II levels in heart and renal tissues; decreased adiponectin and increased inflammatory markers in adipose tissue and spleen. Additionally, OB mice presented a higher damage to proteins and lipoperoxidation and lower activity of antioxidant enzymes in kidney and heart. Correlations were found between autonomic dysfunction with angiotensin II and inflammatory mediators, as well as between inflammation and oxidative stress.

Conclusions: Our results showed that female adult ob/ob mice presented discrete diastolic dysfunction accompanied by autonomic disorder, which is associated with inflammation and oxidative stress in these animals.

The role of novel biomarkers in predicting diabetic nephropathy: a review

Diabetic nephropathy (DN) is one of the microvascular complications of the kidney arising commonly from type 1 diabetes mellitus (T1DM), and occasionally from type 2 diabetes mellitus (T2DM). Microalbuminuria serves as an early indicator of DN risk and a predictor of its progression as well as cardiovascular disease risk in both T1DM and T2DM. Although microalbuminuria remains the gold standard for early detection of DN, it is not a sufficiently accurate predictor of DN risk due to some limitations. Thus, there is a paradigm shift to novel biomarkers which would help to predict DN risk early enough and possibly prevent the occurrence of end-stage kidney disease. These new biomarkers have been broadly classified into glomerular biomarkers, tubular biomarkers, biomarkers of inflammation, biomarkers of oxidative stress, and miscellaneous biomarkers which also include podocyte biomarkers, some of which are also considered as tubular and glomerular biomarkers. Although they are potentially useful for the evaluation of DN, current data still preclude the routine clinical use of majority of them. However, their validation using high-quality and large longitudinal studies is of paramount importance, as well as the subsequent development of a biomarker panel which can reliably predict and evaluate this renal microvascular disease. This paper aims to review the predictive role of these biomarkers in the evaluation of DN.

Terpene glycoside component from Moutan Cortex ameliorates diabetic nephropathy by regulating endoplasmic reticulum stress-related inflammatory responses

ETHNOPHARMACOLOGICAL RELEVANCE

Multiple lines of evidences have suggested that endoplasmic reticulum (ER) stress-related inflammatory responses play a critical role in the pathogenesis of diabetic nephropathy (DN). Moutan Cortex (MC), the root bark of Paeonia suffruticosa Andr., is a well-known traditional Chinese medicine (TCM), which has been used clinically for treating inflammatory diseases in China. The findings from our previous research suggested that terpene glycoside (TG) component of MC possessed favorable anti-inflammatory properties in curing DN. However, the underlying mechanisms of MC-TG for treating DN are still unknown.

AIM OF THE STUDY

To explore the role of ER stress-related inflammatory responses in the progression of DN, and to investigate the underlying protective mechanisms of MC-TG in kidney damage.

MATERIALS AND METHODS

DN rats and advanced glycation end-products (AGEs) induced HBZY-1 cell dysfunction were established to evaluate the protective effect of MC-TG on ameliorating renal injury. Evaluation of pathological lesions was performed by Masson staining and transmission electron microscopy (TEM). Interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), glucose regulated protein 78 (GRP78/Bip), as well as spliced X box binding protein 1(XBP-1(s)) levels in rat serum were detected by an enzyme-linked immunosorbent assay (ELISA). Furthermore, western blotting (WB) was applied to detect the protein expressions including IL-6, MCP-1, intercellular cell adhesion molecule-1 (ICAM-1), GRP78/Bip, XBP-1 (s), phosphorylated inositol-requiring enzyme-1α (p-IRE1α), cleaved activating transcription factor 6 (ATF6), phosphorylated PKR-like endoplasmic reticulum kinase (p-PERK), and phosphorylated nuclear factor κB p65 (p-NF-κB p65) in vivo and in vitro. Immunohistochemistry (IHC) was carried out to determine the phosphorylation of IRE1α and NF-κB p65 in kidney tissues.

RESULTS

Pretreatment with MC-TG could markedly improve renal insufficiency and pathologic changes. It could down-regulate ER stress-related factors GRP78/Bip, XBP-1(s) levels, and also reduce the pro-inflammatory molecules IL-6, MCP-1, and ICAM-1 expressions. Furthermore, a significant decrease in phosphorylation of IRE1α and NF-κB p65 by the treatment of MC-TG.

CONCLUSIONS

These findings indicated that MC-TG ameliorated ER stress-related inflammation in the pathogenesis of DN, wherein the protective mechanism might be associated with the inhibition of IRE1/NF-κB activation. Thus, MC-TG might be a potential therapeutic candidate for the prevention and treatment of DN.

Protodioscin ameliorates fructose-induced renal injury via inhibition of the mitogen activated protein kinase pathway

BACKGROUND

High dietary fructose can cause metabolic syndrome and renal injury.

PURPOSE

The effects of protodioscin on metabolic syndrome and renal injury were investigated in mice receiving high-dose fructose.

METHODS

Mice received 30% (w/v) fructose in water and standard chow for 6 weeks to induce metabolic syndrome and were divided into four groups to receive carboxymethylcellulose sodium, allopurinol (5 mg/kg) and protodioscin (5 and 10 mg/kg) continuously for 6 weeks, respectively. The glucose intolerance, serum uric acid (UA), blood urea nitrogen (BUN), creatinine (Cr), total cholesterol (TC), triglyceride (TG), interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were determined.

RESULTS

Protodioscin significantly improved glucose intolerance and reduced the levels of serum UA, BUN, Cr, TC and TG. Histological examinations showed that protodioscin ameliorated glomerular and tubular pathological changes. Protodioscin significantly reduced renal concentrations of IL-1β, IL-6 and TNF-α by inhibiting the activation of nuclear factor-κB, c-Jun N-terminal kinase, p38 mitogen-activated protein kinase and extracellular signal-regulated kinase. In addition, the effect of protodioscin on the mitogen activated protein kinases (MAPK) pathway was examined.

CONCLUSION

Taken together, protodioscin is a potential drug candidate for high dietary fructose-induced metabolic syndrome and renal injury.

Diabetes mellitus: The linkage between oxidative stress, inflammation, hypercoagulability and vascular complications

BACKGROUND

Vascular complications are the leading cause of morbidity and mortality among patients with type 1 and type 2 diabetes mellitus. These vascular abnormalities result of a chronic hyperglycemic state, which leads to an increase in oxidative stress and inflammatory responses.

AIM

This review addresses the relationships among endothelial dysfunction, hypercoagulability and inflammation and their biomarkers in the development of vascular complications in type 1 and type 2 diabetes.

RESULTS

Inflammation, endothelial dysfunction, and hypercoagulability are correlated to each other, playing an important role in the development of vascular complications in diabetic patients. Moreover, it has been observed that several endothelial, inflammatory and pro-coagulant biomarkers, such as VWF, IL-6, TNF-α, D-dimer and PAI-1, are increased in diabetic patients who have microvascular and macrovascular complications, including nephropathy or cardiovascular disease.

CONCLUSION

It is promising the clinical and laboratory use of endothelial, inflammatory and pro-coagulant biomarkers for predicting the risk of cardiovascular and renal complications in diabetic patients and for monitoring these patients.

Correlation between advanced glycation end-products and the expression of fatty inflammatory factors in type II diabetic cardiomyopathy

Diabetic cardiomyopathy (DCM) is one of the most severe complications of diabetes without a clear pathogenesis. Th is study investigated the adiponectin (APN) and leptin levels in type II DCM, as well as their correlation with advanced glycation end-products (AGEs). From 2011-2013, 78 type II diabetes mellitus (T2DM) cases (40-65 years old) in the Taian region were randomly selected. Based on the results of colour Doppler ultrasonography and coronary angiography, the cases were divided into a simple T2DM group (40 cases) and a DCM group (38 cases). Forty healthy subjects were used as normal control (NC). An enzyme-linked immunosorbent assay was performed to determine the levels of fa tty inflammatory factors such as APN, leptin and AGEs, and a correlation analysis was conducted. In the T2DM group, the APN levels were decreased but the leptin and AGE levels were significantly increased compared to the NC group. In the DCM group, the APN levels were decreased but the leptin and AGE levels were significantly increased (P<0.01) compared to the T2DM group. Th e AGE levels were positively correlated with disease progression and with fasting plasma glucose levels, glycated haemoglobin, insulin resistance and leptin, but were negatively correlated with APN levels. Additionally, the APN and leptin levels were independently related to the AGE levels. Fatty inflammatory factors play a significant role in the progression of both simple T2DM and DCM. Th e results of this study revealed the pathogenesis of DCM and indicated the potential significance of AGEs in DCM prevention and treatment.

Elevated Concentration of Interferon-Inducible Protein of 10 kD (IP-10) Is Associated With Coronary Atherosclerosis

Several studies have shown that various chemokines are more highly expressed in atherosclerotic plaques than in normal vessel walls. In the present study, we investigated the relationship between coronary atherosclerosis and noteworthy chemokines, including interferon-inducible protein of 10 kD (IP-10); monocyte chemoattractant protein 1 (MCP-1); regulated on activation, normal T-cell expressed and secreted (RANTES); and high-sensitivity C-reactive protein (hsCRP), an established marker of atherosclerotic disease. We studied 28 patients who underwent coronary angiography because of suspected coronary artery disease (CAD). CAD was defined as stenosis of more than 50% of the vessel diameter on coronary angiograms. Blood samples were obtained both from the aorta and the coronary sinus (CS) just before coronary angiography. Relative to CAD (-) patients, those who were CAD (+) tended to have higher plasma concentrations of IP-10 in the aorta, as well as significantly higher transcoronary concentration gradients of circulating IP-10. There were no significant differences between the two groups in aortic plasma concentrations or transcoronary concentration gradients of MCP-1, RANTES, and hsCRP. Furthermore, both the aortic plasma concentrations and transcoronary concentration gradients of IP-10 correlated with the Gensini score (r = 0.58 and r = 0.63, respectively, P < 0.01), while the plasma MCP-1, RANTES, and serum hsCRP concentrations did not. This study suggests that IP-10 is a good surrogate marker of coronary atherosclerosis.

sVCAM-1 concentration and carotid IMT values in patients with acute myocardial infarction--Atherosclerotic markers of the presence, progress and prognosis

PURPOSE

Vascular cell adhesion molecule 1 (VCAM-1) plays a role in the adhesion and migration of leukocytes from blood to arterial intima and correlate with the development of atherosclerosis. The aim of the study was to establish whether soluble VCAM-1 (sVCAM-1) may act as an independent risk factor of coronary artery disease occurrence and whether it may reflect a degree of its advancement, if sVCAM-1 has a potential relation with intima-media thickness measurement (IMT), if sVCAM-1 may be useful as a predictor of further cardiovascular events.

MATERIAL AND METHODS

The study group was composed of 78 patients who were consecutively hospitalized in 2010-2011 due to myocardial infarction (MI). Selected clinical and biochemical risk factors were assessed, sVCAM-1 concentrations and IMT were measured.

RESULTS

Concentrations of sVCAM-1 were significantly higher in the study group as compared to the healthy controls. No significant dependence between sVCAM-1 concentration and the value of IMT in carotid arteries was found. There were no significantly statistical differences between the advancement of coronary artery changes and sVCAM-1 concentration. During the follow-up that lasted from 2 to 4 years (average period - 2.8 years), 4 patients died in the study group (5.1%). sVCAM-1 concentrations (but not IMT values) were significantly statistically higher in the group of patients who died (2248.5±443.5 vs. 990.2±433.6, p=0.0003).

CONCLUSIONS

sVCAM-1 concentrations are useful indicators of the presence of atherosclerosis in coronary arteries, but not its advancement. sVCAM-1 (but not IMT) can be a predictive indicator of an increased risk of death during follow-up in patients after myocardial infarction.

Protection of vascular endothelial cells from high glucose-induced cytotoxicity by emodin

Induction of endothelial cytotoxicity by hyperglycemia in diabetes has been widely accepted. Emodin is a natural anthraquinone in rhubarb used for treatment of diabetes, but its mechanism of action is not fully understood. This study aimed to examine the potential beneficial effects of emodin on endothelial cytotoxicity caused by high glucose milieu. Culture of human umbilical vein endothelial cells (HUVECs) with high concentrations of glucose resulted in damage to the cells, leading to decreased formazan products by 14-27%, reduced DNA contents by 12-19%, and increased hypodiploid apoptosis by 40-109%. These adverse effects of high glucose could be prevented to a large extent by co-culture with 3 μM of emodin which per se did not affect HUVECs viability. In addition, CCL5 expression of HUVECs cultured in high glucose medium was significantly elevated at both mRNA and protein levels, an effect abolished after treatment with emodin. Moreover, the enhanced adhesion of monocytes to HUVECs (2.1-2.2 fold over control) and elevated chemotaxis activities (2.3-2.4 fold over control) in HUVECs cultured in high glucose medium were completely reversed by emodin. Emodin also suppressed activation of p38 MAPK and ERK1/2 due to high glucose. Our data demonstrated that endothelial cytotoxicity occurred clearly when HUVECs were exposed to high glucose milieu and emodin was able to alleviate the impairments. The protective effects of emodin might be related to the inhibition of CCL5 expression and subsequent cell stress/inflammatory events possibly mediated by activation of MAPK signaling pathways.

Advanced glycation end products increase expression of S100A8 and A9 via RAGE-MAPK in rat dental pulp cells

OBJECTIVE

Advanced glycation end products (AGE) are involved in the progression of diabetic complications. Although our previous reports show that AGE increased dental pulp calcification, AGE accumulation is also associated with inflammation. This study examined AGE effect on the expression of inflammation factors using rat dental pulp tissues and cell cultures.

MATERIALS AND METHODS

Receptor for AGE (RAGE), S100A8, S100A9, and interleukin (IL)-1β were selected as inflammation parameters. Rat dental pulp cells were cultured and treated with AGE, and the effects were determined by real-time PCR. An anti-RAGE antibody or MAPK pathway inhibitors (PD98059, SB203580, and SP60012) were used to investigate AGE signaling pathway.

RESULTS

The mRNA levels of RAGE, S100A8, S100A9, and IL-1β were higher in diabetic pulp tissues. AGE increased mRNA expressions of S100A8, S100A9, and IL-1β in cultured dental pulp cells. In the presence of anti-RAGE antibody, AGE did not increase in S100A8 or S100A9 expressions. The AGE-induced increases in S100A8 and S100A9 were inhibited by PD98059 and SB203580, respectively.

CONCLUSIONS

Advanced glycation end products increased mRNA expression of S100A8, S100A9, and IL-1β under diabetic pulp conditions, and AGE-induced increases in S100A8 and S100A9 expressions may be associated with the RAGE-MAPK signaling pathway.

Microinflammation in the pathogenesis of diabetic nephropathy

Diabetic nephropathy is the leading cause of end‐stage renal failure in developed countries. Furthermore, diabetic nephropathy is related to the risk of cardiovascular diseases and an increase in mortality of diabetic patients. Several factors are involved in the development of nephropathy, including glomerular hyperfiltration, oxidative stress, accumulation of advanced glycation end‐products, activation of protein kinase C, acceleration of the polyol pathway and over‐expression of transforming growth factor‐β. Recently, accumulated data have emphasized the critical roles of chronic low‐grade inflammation, ‘microinflammation’, in the pathogenesis of diabetic nephropathy, suggesting that microinflammation is a common mechanism in the development of diabetic vascular complications. Expression of cell adhesion molecules, chemokines and pro‐inflammatory cytokines are increased in the renal tissues of diabetic patients and animals. Deficiency of pro‐inflammatory molecules results in amelioration of renal injuries after induction of diabetes in mice. Plasma and urinary levels of cytokines, chemokines and cell adhesion molecules, are elevated and correlated with albuminuria. Several kinds of drugs that have anti‐inflammatory actions as their pleiotropic effects showed renoprotective effects on diabetic animals. Modulation of the inflammatory process prevents renal insufficiency in diabetic animal models, suggesting that microinflammation is one of the promising therapeutic targets for diabetic nephropathy, as well as for cardiovascular diseases.

Estimated glomerular filtration rate decline is a better risk factor for outcomes of systemic disease-related nephropathy than for outcomes of primary renal diseases

BACKGROUND

Currently, the contribution of kidney function decline in renal and patient outcomes is unclear. There are few data on the associations of different etiologies of estimated glomerular filtration rate (eGFR) decline with outcomes in multidisciplinary care. The purpose of this investigation was to establish whether eGFR decline in patients with disease is an important risk factor for developing end-stage renal disease (ESRD) and death.

METHODS

From December 1, 2001 to December 31, 2011, 5097 adults with chronic kidney disease (CKD) received biochemical tests, physical examinations, a pathological examination, and a comprehensive questionnaire. We used linear regression models and multivariate Cox proportional hazards model to examine the outcome of eGFR decline in renal diseases with different etiologies.

RESULTS

Mean age was 68.1±16.1 (standard deviation, SD) years, and 63.3% patients were male. In the studied cohort, 58.2% of the patients had systemic disease-related nephropathy (SDRN), 29.4% had primary renal diseases (PRDs), and 12.4% had other etiologies. The eGFR decline in SDRN had a significant association with dialysis in the Cox proportional hazards model [crude hazard ratio (HR) = 1.07, 95% confidence interval (CI), 1.04 to 1.10; adjusted HR 1.05, 95% CI, 1.02 to 1.08]. Diabetic nephropathy (DN) had the most severe eGFR decline in CKD stages 3, 4, and 5, and all contributed to the initiation of dialysis and death regardless of whether DN with or without eGFR decline was considered to be the cause. Although hypertensive nephropathy (HN) was related to significant acceleration of eGFR decline, it did not lead to poor outcome. There were still discrepancies between eGFR decline and outcomes in PRDs, hypertensive nephropathy, and lupus nephritis.

CONCLUSIONS

eGFR decline and CKD staging provide an informative guide for physicians to make proper clinical judgments in the treatment of CKD, especially SDRN. Poor control of the underlying systemic disease will thus lead to more rapid progression of SDRN.

Low serum bilirubin concentration is a novel risk factor for the development of albuminuria in patients with type 2 diabetes

OBJECTIVE

Bilirubin has been recognized as an important endogeneous antioxidant. Previous studies reported that bilirubin could prevent atherosclerosis. The aim of this study was to investigate if serum bilirubin concentration could be a predictor for the development of albuminuria in patients with type 2 diabetes.

MATERIALS AND METHODS

We measured serum bilirubin in 320 consecutive patients with normoalbuminuria. We performed follow-up study to assess the development of albuminuria, mean interval of which was 3.2±0.9years. Cox proportional hazards regression was used to examine the relationship between serum bilirubin concentration and the development of albuminuria.

RESULTS

During follow-up duration, 43 patients have developed albuminuria. In multivariate analysis, after adjusting for comprehensive risk factors, the risk of developing albuminuria was higher in the lowest quartile of serum bilirubin concentrations than that in the highest quartile of serum bilirubin concentrations (Hazard ratio, 5.76; 95% CI, 1.65 to 24.93).

CONCLUSIONS

Low serum bilirubin concentration could be a novel risk factor for the development of albuminuria in patients with type 2 diabetes.

Silent diabetic nephropathy

AIM: To examine the risk of renal events in patients with biopsy-proven diabetic nephropathy (DN) and its possible associated factors.

METHODS: Clinical and histological data of 60 patients diagnosed with diabetic nephropathy were retrospectively collected. Patients with evidence or suspicion of other nephropathies were excluded from the study. The final event was defined as renal replacement therapy (RRT) initiation or progression of chronic kidney disease (CKD), according to the KDIGO 2012 definition of a decrease in CKD category and a decrease in GFR of 25% or more.

RESULTS: A total of 45 patients with a follow-up of at least 3 mo were included. Most of the patients presented type 2 DM, with a mean age of 58.3 years old. The time of evolution of DM was 9.6 ± 7.8 years, although in 13 patients, it was less than 5 years. A total of 62% of patients reached the final event in a median period of 3.4 years (95%CI: 2.1-4.7), with 21 of them requiring dialysis. The factors that were independently associated with renal survival were estimated glomerular filtration rate (eGFR) at the time of biopsy, cardiovascular disease (CVD) history and HbA1c less than 7%. Therefore, for each 10 mL/min per 1.73 m² reduction in eGFR, we obtained a DN progression risk of HR = 2 (1.3-3.0) (P = 0.001); patients with CVD were at greater risk for DN progression (HR = 2.8, 1.1-7.1, P = 0.032), and CKD patients with HbA1c < 7% demonstrated greater renal risk than patients with HbA1c ≥ 7%, with an HR of 2.9 (1.0-8.4) (P = 0.054).

CONCLUSION: A past history of CVD is a risk factor for DN progression. Levels of HbA1c less than 7% could favor an eGFR decrease in these patients.

Resistance training decreases serum inflammatory markers in diabetic rats

Inflammation plays an important role in the genesis and progression of diabetes. The purpose of this study was to investigate the effect of resistance training on serum levels of some inflammatory markers associated with diabetes mellitus. Twenty-four male Wistar rats (290 ± 19 g) were randomly divided into three groups: non-diabetic control (non-DC), diabetic control (DC), and diabetic trained (DT). Animals in DT group were subjected to a resistance training program with the use of a ladder (3 days/week, for 4 weeks). Body weight, serum high sensitivity C-reactive protein (hs-CRP), interleukin (IL)-6, tumor necrosis factor (TNF)-α, fasting glucose, and insulin were measured. Four weeks of resistance training decreased serum levels of TNF-α, hs-CRP, and IL-6 in diabetic rats when compared with DC animals. We conclude that resistance training with appropriate intensity, duration, and recovery between exercise bouts has marked anti-inflammatory effects on diabetic rats. This may be an efficient strategy to protect against some diabetic complications.

Effects of exercise on inflammation markers in type 2 diabetic subjects

Endothelial dysfunction and plasma markers of inflammation are significantly increased in type 2 diabetics. Several proinflammatory cytokines, acute-phase proteins, and cell adhesion molecules, such as C-reactive protein (CRP), interleukines (IL), and tumor necrosis factor alpha (TNF-α), seem to play a role in the low-grade systemic inflammation observed in these subjects. Lifestyle changes are necessary to prevent atherosclerosis and cardiovascular events. Physical exercise is known to reduce markers of inflammation by decreasing adipocytokine production and cytokine release from skeletal muscles, endothelial cells, and immune system and also improving antioxidant status. In type 2 diabetics, aerobic and resistance training have different effects on cytokine levels, and the differences in the modalities of exercise (type, duration, and intensity) and especially in the examined population could produce different results. Recent research showed that combined exercise has greater anti-inflammatory effects than aerobic or resistance exercise alone causing a deepest decrease in CRP, IL-6, IL-1β, TNF-α, leptin, and resistin and a higher increase in anti-inflammatory cytokines such as IL-4, IL-10, and adiponectin.

Association between high-sensitivity C-reactive protein and left ventricular diastolic function assessed by echocardiography in patients with cardiovascular risk factors

High-sensitivity C-reactive protein (hsCRP) has been demonstrated to play a causal role in atherosclerosis and to predict cardiovascular events in the general population. On the other hand, left ventricular (LV) hypertrophy and diastolic dysfunction assessed by echocardiography can also predict cardiovascular events in patients with cardiovascular risk factors. However, there are few data regarding the relationships among hsCRP, LV hypertrophy, and diastolic function. We examined the relationships among hsCRP, LV hypertrophy, and diastolic function in 185 patients (65±11 years), who had no overt heart disease, but had cardiovascular risk factors, including hypertension, diabetes, and dyslipidemia. Echocardiography was performed to measure the left ventricular mass index (LVMI) as a parameter of LV hypertrophy. LV diastolic function was assessed by the ratio (E/A) of early (E) and late (A) diastolic transmitral flows, early diastolic mitral annular velocity (E'), and the ratio (E/E') of E to E' using Doppler echocardiography. The hsCRP was correlated with LVMI (r=0.228, p=0.002), E' (r=-0.276, p<0.001), and E/E' (r=0.419, p<0.001). The E/E' as a parameter of LV diastolic function showed the closest correlation to hsCRP. These results indicate that elevated hsCRP reflects LV diastolic dysfunction rather than LV hypertrophy. We therefore suggest that hsCRP may be a marker of subclinical LV diastolic dysfunction in patients with cardiovascular risk factors.