Traditional Chinese medicine and its active substances reduce vascular injury in diabetes via regulating autophagic activity.

Due to its high prevalence, poor prognosis, and heavy burden on healthcare costs, diabetic vascular complications have become a significant public health issue. Currently, the molecular and pathophysiological mechanisms underlying diabetes-induced vascular complications remain incompletely understood. Autophagy, a highly conserved process of lysosomal degradation, maintains intracellular homeostasis and energy balance via removing protein aggregates, damaged organelles, and exogenous pathogens. Increasing evidence suggests that dysregulated autophagy may contribute to vascular abnormalities in various types of blood vessels, including both microvessels and large vessels, under diabetic conditions. Traditional Chinese medicine (TCM) possesses the characteristics of "multiple components, multiple targets and multiple pathways," and its safety has been demonstrated, particularly with minimal toxicity in liver and kidney. Thus, TCM has gained increasing attention from researchers. Moreover, recent studies have indicated that Chinese herbal medicine and its active compounds can improve vascular damage in diabetes by regulating autophagy. Based on this background, this review summarizes the classification, occurrence process, and related molecular mechanisms of autophagy, with a focus on discussing the role of autophagy in diabetic vascular damage and the protective effects of TCM and its active compounds through the regulation of autophagy in diabetes. Moreover, we systematically elucidate the autophagic mechanisms by which TCM formulations, individual herbal extracts, and active compounds regulate diabetic vascular damage, thereby providing new candidate drugs for clinical treatment of vascular complications in diabetes. Therefore, further exploration of TCM and its active compounds with autophagy-regulating effects holds significant research value for achieving targeted therapeutic approaches for diabetic vascular complications.

Evaluation of salivary glycopatterns based diagnostic models for prediction of diabetic vascular complications.

Diabetic vascular complications (DVC) are the main cause of death in diabetic patients. However, there is a lack of effective biomarkers or convenient methods for early diagnosis of DVC. In this study, the salivary glycopatterns from 130 of healthy volunteers (HV), 139 patients with type 2 diabetes mellitus (T2DM) and 167 patients with DVC were case-by-case analyzed by using lectin microarrays. Subsequently, diagnostic models were developed using logistic regression and machine learning algorithms based on the data of lectin microarrays in training set. The performance of diagnostic models was evaluated in an independent blind cohort. The results of lectin microarrays indicated that the glycopatterns identified by 16 lectins (e.g. BS-I, PWM and EEL) were significantly altered in DVC patients compared with patients with T2DM, which suggested the alterations in salivary glycopatterns could reflect onset of DVC. Notably, K-Nearest Neighbor (KNN) model exhibited better performance for distinguishing DVC (accuracy: 0.939) than other models in blind cohort. The integrated classifier, which combined three machine learning models, exhibited a higher overall accuracy (≥ 0.933) than other models in blind cohort. Our study provided a cost-effective and non-invasive method for auxiliary diagnosis DVC based on the combination of salivary glycopatterns and machine learning algorithms.

Network pharmacology, molecular docking, and in vitro experimental verification of the mechanism of Guanxining in treating diabetic atherosclerosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Guanxinning(GXN) tablet is a patented traditional Chinese medicine widely used to prevent and treat cardiovascular diseases. However, its potential mechanism and target in anti-diabetic atherosclerosis have not been clarified. AIM: The aim of this study was to investigate the underlying targets and mechanisms of action GXN in the treatment of diabetic atherosclerosis, employing a combination of network pharmacology, molecular docking, and in vitro experimental verification. METHODS: We predicted the core components and targets of GXN in the treatment of diabetic atherosclerosis through various databases, and made analysis and molecular docking. In vitro, we induced injury in human umbilical vein endothelial cells using glucose/palmitate and observed the effects of GXN on cellular damage high-glucose and high-fat conditions, subsequently elucidating its molecular mechanisms. RESULTS: A total of 14 active components and 157 targets of GXN were identified. Using the PPI network, we selected 9 core active components and 20 targets of GXN. GO functional analysis revealed that these targets were primarily associated with apoptosis signaling pathways in response to endoplasmic reticulum stress and reactive oxygen species responses. Molecular docking confirmed the strong binding affinities of the primary active components of GXN with ERN1, MAPK1 and BECN1. In vitro experiments demonstrated the ability of GXN to restore endothelial cell activity, enhance cell migration and inhibit sICAM secretion, and upregulate the expression of endoplasmic reticulum stress-related proteins (IRE1, XBP1) and autophagy-related proteins (Beclin1, LC3A, and LC3B), while simultaneously inhibiting endothelial cell apoptosis under high-glucose and high-fat conditions. CONCLUSIONS: Our findings suggest that GXN can potentially safeguard endothelial cells from the adverse effects of high-glucose and high-fat by modulating the interactions between endoplasmic reticulum stress and autophagy. Therefore, GXN is a promising candidate for the prevention and treatment of diabetic atherosclerosis.

Diabetic microvascular disease in non-classical beds: the hidden impact beyond the retina, the kidney, and the peripheral nerves.

Diabetes microangiopathy, a hallmark complication of diabetes, is characterised by structural and functional abnormalities within the intricate network of microvessels beyond well-known and documented target organs, i.e., the retina, kidney, and peripheral nerves. Indeed, an intact microvascular bed is crucial for preserving each organ's specific functions and achieving physiological balance to meet their respective metabolic demands. Therefore, diabetes-related microvascular dysfunction leads to widespread multiorgan consequences in still-overlooked non-traditional target organs such as the brain, the lung, the bone tissue, the skin, the arterial wall, the heart, or the musculoskeletal system. All these organs are vulnerable to the physiopathological mechanisms that cause microvascular damage in diabetes (i.e., hyperglycaemia-induced oxidative stress, inflammation, and endothelial dysfunction) and collectively contribute to abnormalities in the microvessels' structure and function, compromising blood flow and tissue perfusion. However, the microcirculatory networks differ between organs due to variations in haemodynamic, vascular architecture, and affected cells, resulting in a spectrum of clinical presentations. The aim of this review is to focus on the multifaceted nature of microvascular impairment in diabetes through available evidence of specific consequences in often overlooked organs. A better understanding of diabetes microangiopathy in non-target organs provides a broader perspective on the systemic nature of the disease, underscoring the importance of recognising the comprehensive range of complications beyond the classic target sites.

Endothelial progenitor cells as biomarkers of diabetes-related cardiovascular complications.

Diabetes mellitus (DM) constitutes a chronic metabolic disease characterized by elevated levels of blood glucose which can also lead to the so-called diabetic vascular complications (DVCs), responsible for most of the morbidity, hospitalizations and death registered in these patients. Currently, different approaches to prevent or reduce DM and its DVCs have focused on reducing blood sugar levels, cholesterol management or even changes in lifestyle habits. However, even the strictest glycaemic control strategies are not always sufficient to prevent the development of DVCs, which reflects the need to identify reliable biomarkers capable of predicting further vascular complications in diabetic patients. Endothelial progenitor cells (EPCs), widely known for their potential applications in cell therapy due to their regenerative properties, may be used as differential markers in DVCs, considering that the number and functionality of these cells are affected under the pathological environments related to DM. Besides, drugs commonly used with DM patients may influence the level or behaviour of EPCs as a pleiotropic effect that could finally be decisive in the prognosis of the disease. In the current review, we have analysed the relationship between diabetes and DVCs, focusing on the potential use of EPCs as biomarkers of diabetes progression towards the development of major vascular complications. Moreover, the effects of different drugs on the number and function of EPCs have been also addressed.

Common mechanisms underlying diabetic vascular complications: focus on the interaction of metabolic disorders, immuno-inflammation, and endothelial dysfunction.

Diabetic vascular complications (DVCs), including macro- and micro- angiopathy, account for a high percentage of mortality in patients with diabetes mellitus (DM). Endothelial dysfunction is the initial and role step for the pathogenesis of DVCs. Hyperglycemia and lipid metabolism disorders contribute to endothelial dysfunction via direct injury of metabolism products, crosstalk between immunity and inflammation, as well as related interaction network. Although physiological and phenotypic differences support their specified changes in different targeted organs, there are still several common mechanisms underlying DVCs. Also, inhibitors of these common mechanisms may decrease the incidence of DVCs effectively. Thus, this review may provide new insights into the possible measures for the secondary prevention of DM. And we discussed the current limitations of those present preventive measures in DVCs research. Video Abstract.

Ethnic disparities of vascular complications in pre-diabetes, undiagnosed diabetes, and newly diagnosed diabetes.

In the U.S., ethnic minorities with pre-diabetes, undiagnosed type 2 diabetes (T2D), and newly diagnosed T2D had a higher prevalence of microvascular complications than non-Hispanic Whites and exhibited distinct risk factors, whereas Whites had a higher rate of cardiovascular disease.

Correlation Between Blood Glucose Indexes Generated by the Flash Glucose Monitoring System and Diabetic Vascular Complications.

Objective: To discuss the relationship between time in range (TIR) which is deprived of the FGMS and the risk of diabetic vascular complications and to provide a theoretical foundation for the clinical application of TIR and other FGMS-deprived indexes. Methods: Patients with T2DM who wore the FGMS sensor continuously were enrolled. Relevant indexes such as TIR, time below range (TBR), time above range (TAR), a standard deviation of blood glucose (SDBG), coefficient of variation of blood glucose (CV), and mean amplitude of glycemic excursion (MAGE) generated by the FGMS were recorded, and the risk of diabetic vascular complications were followed up for one year. The TIR was measured by continuous glucose monitoring at baseline, and patients were grouped according to TIR every 20%. Finally, the Cox proportional hazards regression model was used to estimate the association of different levels of TIR with different rates of diabetic vascular complications. Results: TIR was negatively correlated with HbA1C, CV, SDBG, and amplitude of glycemic excursion (MV), wherein, the lower the TIR, the higher the HbA1C, CV, SDBG, and MV. TIR in the diabetic microvascular complication was significantly lower than that in the non-microvascular complication group, and the difference was statistically significant. TIR <40% was identified as a risk factor for DN, DPN, and DR according to the risk assessment. The mean TAR in the DN group was significantly higher than that in the non-DN group. TAR, CV, SD, MAGE, and HbA1C in the DR group were significantly higher than those in the non-DR group. TAR, ABG, CV, SD, MAGE, and HbA1C in the DPN group were significantly higher than those in the non-DPN group. Conclusion: The relationships between the TIR and the prevalence and risk of diabetic vascular complications and the HbA1C may be negative. Other CGM-deprived indexes such as CV and MV should be integrated into glycemic control and diabetes complication prediction.

Nox4 as a novel therapeutic target for diabetic vascular complications.

Diabetic vascular complications can affect both microvascular and macrovascular. Diabetic microvascular complications, such as diabetic nephropathy, diabetic retinopathy, diabetic neuropathy, and diabetic cardiomyopathy, are believed to be caused by oxidative stress. The Nox family of NADPH oxidases is a significant source of reactive oxygen species and plays a crucial role in regulating redox signaling, particularly in response to high glucose and diabetes mellitus. This review aims to provide an overview of the current knowledge about the role of Nox4 and its regulatory mechanisms in diabetic microangiopathies. Especially, the latest novel advances in the upregulation of Nox4 that aggravate various cell types within diabetic kidney disease will be highlighted. Interestingly, this review also presents the mechanisms by which Nox4 regulates diabetic microangiopathy from novel perspectives such as epigenetics. Besides, we emphasize Nox4 as a therapeutic target for treating microvascular complications of diabetes and summarize drugs, inhibitors, and dietary components targeting Nox4 as important therapeutic measures in preventing and treating diabetic microangiopathy. Additionally, this review also sums up the evidence related to Nox4 and diabetic macroangiopathy.

Down-regulation of WWP2 aggravates Type 2 diabetes mellitus-induced vascular endothelial injury through modulating ubiquitination and degradation of DDX3X.

BACKGROUND: Endothelial injury caused by Type 2 diabetes mellitus (T2DM) is considered as a mainstay in the pathophysiology of diabetic vascular complications (DVCs). However, the molecular mechanism of T2DM-induced endothelial injury remains largely unknown. Here, we found that endothelial WW domain-containing E3 ubiquitin protein ligase 2 (WWP2) act as a novel regulator for T2DM-induced vascular endothelial injury through modulating ubiquitination and degradation of DEAD-box helicase 3 X-linked (DDX3X). METHODS: Single-cell transcriptome analysis was used to evaluate WWP2 expression in vascular endothelial cells of T2DM patients and healthy controls. Endothelial-specific Wwp2 knockout mice were used to investigate the effect of WWP2 on T2DM-induced vascular endothelial injury. In vitro loss- and gain-of-function studies were performed to assess the function of WWP2 on cell proliferation and apoptosis of human umbilical vein endothelial cells. The substrate protein of WWP2 was verified using mass spectrometry, coimmunoprecipitation assays and immunofluorescence assays. The mechanism of WWP2 regulation on substrate protein was investigated by pulse-chase assay and ubiquitination assay. RESULTS: The expression of WWP2 was significantly down-regulated in vascular endothelial cells during T2DM. Endothelial-specific Wwp2 knockout in mice significantly aggravated T2DM-induced vascular endothelial injury and vascular remodeling after endothelial injury. Our in vitro experiments showed that WWP2 protected against endothelial injury by promoting cell proliferation and inhibiting apoptosis in ECs. Mechanically, we found that WWP2 is down-regulated in high glucose and palmitic acid (HG/PA)-induced ECs due to c-Jun N-terminal kinase (JNK) activation, and uncovered that WWP2 suppresses HG/PA-induced endothelial injury by catalyzing K63-linked polyubiquitination of DDX3X and targeting it for proteasomal degradation. CONCLUSION: Our studies revealed the key role of endothelial WWP2 and the fundamental importance of the JNK-WWP2-DDX3X regulatory axis in T2DM-induced vascular endothelial injury, suggesting that WWP2 may serve as a new therapeutic target for DVCs.

Associations of Obesity Indices with Bone Mineral Densities and Risk of Osteoporosis Stratified Across Diabetic Vascular Disease in T2DM Patients.

Objective: To evaluate associations of obesity indices with bone mineral densities (BMD) and risk of osteoporosis in T2DM patients totally and stratified across presence of any diabetic cardiovascular complications. Methods: Cross-sectional analyses of baseline information on a cohort of 250 T2DM patients were conducted in Xiamen, China. Obesity indices included body weight, height, body mass index (BMI), waist and waist hip ratio (WHR). BMD was measured using dual-energy X-ray absorptiometry at three different sites, and osteoporosis was defined based on the minimum T-scores of BMD. Presence of any diabetic vascular complications was confirmed by checking their medical records histories. Results: Among the 250 T2DM patients, 50 (20.0%) were defined as osteoporosis. Multivariable linear regression and multivariable logistic regression analyses showed that igher obesity indices, including body weight, BMI and waist, but neither body height nor waist hip ratio, were positively associated with the minimum T-scores of BMD and had significantly decreased risk of osteoporosis. Stratified analyses across presence of any of diabetic vascular complications showed similar results for those with any of diabetic vascular complications, while no significant association between obesity indices and minimum T-scores of BMD was found for those without. Postmenopausal women (vs men) and ever drinking were significantly associated with increased risk of osteoporosis, and the adjusted odds ratios (95% CIs) were 5.165 (1.762-15.138, p = 0.003) and 3.789 (1.087-13.214, p = 0.037), respectively. None of metabolic profiles, including systolic and diastolic blood pressure, triglyceride, total cholesterol, high-density lipoprotein cholesterol, HbA1c and blood uric acid, was significantly associated with either minimum T-scores of BMD or risk of osteoporosis. Conclusion: Associations of obesity indices with either BMD or risk of osteoporosis in T2DM patients varied by presence of any diabetic vascular complication and should be not interpreted as causal without considering the often-unmeasured effect modification by health status.

Association of Time in Range with Endothelial Injury in Patients with Type 2 Diabetes Treated with Exenatide.

INTRODUCTION: We aimed to investigate whether treatment with exenatide could increase time in range (TIR) and decrease glycemic variability, and to evaluate the association between TIR and endothelial injury in patients with type 2 diabetes mellitus (T2DM). METHODS: Two-hundred patients with T2DM treated with exenatide for 16 weeks were included in this study. Seven-point fingerstick blood glucose was used to evaluate derived TIR and glycemic variability. The serum levels of soluble endothelial cell protein C receptor (sEPCR) and von Willebrand factor (vWF) were measured. Ninety-three patients having the data of endothelial injury markers were categorized as derived TIR > 70% or ≤ 70% after the treatment and the association between TIR and endothelial injury were evaluated. RESULTS: Treatment with exenatide for 16 weeks resulted in a significant reduction in fasting blood glucose, postprandial 2 h blood glucose, and glycated hemoglobin A1c (HbA1c) levels in patients with T2DM. Compared with baseline, derived TIR value was significantly increased [85.7 (57.1, 100.0) % vs. 42.9 (14.9, 71.4) %, P < 0.001], and the parameters of glycemic variability were remarkably decreased after the treatment. After the treatment, serum sEPCR level was significantly decreased from baseline in patients with TIR > 70% [74.5 (32.8, 122.5) ng/mL vs. 96.9 (48.5, 150.9) ng/mL, P = 0.006] but not in those with TIR ≤ 70%; serum vWF level was remarkably decreased in patients with TIR > 70% [from 1166.2 (848.1, 1335.5) mIU/mL to 907.4 (674.3, 1335.1) mIU/mL, P = 0.001] while this effect was modest in those with TIR ≤ 70%. CONCLUSIONS: Treatment with exenatide increases TIR and decreases glycemic variability in patients with T2DM. Moreover, the amelioration of endothelial injury is more pronounced in patients with TIR > 70% after the treatment. TRIAL REGISTRATION: ChiCTR-IPR-15006558 (registered, 27 May 2015).

Salvianolic acid A promotes mitochondrial biogenesis and function via regulating the AMPK/PGC-1α signaling pathway in HUVECs.

Mitochondrial dysregulation is an important pathology that leads to endothelial dysfunction, and the occurrence and development of cardiovascular diseases. Salvianolic acid A (SAA) has been demonstrated to be effective in the treatment of vascular complications of type 2 diabetes mellitus. Limited information has been reported on the effects of SAA on mitochondrial function in endothelial cells. In the present study, the effects of SAA on mitochondrial biogenesis and the related underlying mechanisms were investigated in human umbilical vein endothelial cells (HUVECs). Mitotracker red staining and transmission electron microscopy were used to evaluate the effect of SAA on mitochondrial quality. The effect of SAA treatment on mitochondrial DNA/nuclear DNA ratio of HUVECs was detected by real-time quantitative PCR. Western blot was used to determine the protein expression levels of complex III and Complex IV of mitochondrial oxidative phosphorylation subunit, and ATP production was determined by ATP test kit. Real-time quantitative PCR and Western blot were used to determine the effects of SAA on the expression of peroxisome proliferator-activated receptor γ coactivator (PGC-1α) and its target genes nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM) proteins and genes. Finally, in the presence of 5'AMP-activated protein kinase (AMPK) specific inhibitors, the expression of PGC-1α, NRF1 and TFAM proteins and the phosphorylation levels of AMPK and Acetyl CoA Carboxylase (ACC) were detected by Western blot or real-time quantitative PCR. The results showed that SAA treatment significantly promoted mitochondrial biogenesis and enhanced mitochondrial function of HUVECs. SAA significantly increased the expression levels of PGC-1α and its target genes NRF1 and (TFAM), a key regulator of mitochondrial biogenesis in HUVECs. These enhancements were accompanied by significantly increased phosphorylation of AMPK and ACC, and were significantly inhibited by specific AMPK inhibitors. These results suggest that SAA may promote mitochondrial biogenesis in endothelial cells by activating the AMPK-mediated PGC-1α/TFAM signaling pathway. These data provide new insights into the mechanism of action of SAA in treating diabetic vascular complications.

Human umbilical cord-derived mesenchymal stem cells not only ameliorate blood glucose but also protect vascular endothelium from diabetic damage through a paracrine mechanism mediated by MAPK/ERK signaling.

BACKGROUND: Endothelial damage is an initial step of macro- and micro-vasculature dysfunctions in diabetic patients, accounting for a high incidence of diabetic vascular complications, such as atherosclerosis, nephropathy, retinopathy, and neuropathy. However, clinic lacks effective therapeutics targeting diabetic vascular complications. In field of regenerative medicine, mesenchymal stem cells, such as human umbilical cord-derived MSCs (hucMSCs), have great potential in treating tissue damage. METHODS: To determine whether hucMSCs infusion could repair diabetic vascular endothelial damage and how it works, this study conducted in vivo experiment on streptozotocin-induced diabetic rat model to test body weight, fasting blood glucose (FBG), serum ICAM-1 and VCAM-1 levels, histopathology and immunohistochemical staining of aorta segments. In vitro experiment was further conducted to determine the effects of hucMSCs on diabetic vascular endothelial damage, applying assays of resazurin staining, MTT cell viability, wound healing, transwell migration, and matrigel tube formation on human umbilical vein endothelial cells (HUVECs). RNA sequencing (RNAseq) and molecular experiment were conducted to clarify the mechanism of hucMSCs. RESULTS: The in vivo data revealed that hucMSCs partially restore the alterations of body weight, FBG, serum ICAM-1 and VCAM-1 levels, histopathology of aorta and reversed the abnormal phosphorylation of ERK in diabetic rats. By using the conditioned medium of hucMSCs (MSC-CM), the in vitro data revealed that hucMSCs improved cell viability, wound healing, migration and angiogenesis of the high glucose-damaged HUVECs through a paracrine action mode, and the altered gene expressions of IL-6, TNF-α, ICAM-1, VCAM-1, BAX, P16, P53 and ET-1 were significantly restored by MSC-CM. RNAseq incorporated with real-time PCR and Western blot results clarified that high glucose activated MAPK/ERK signaling in HUVECs, while MSC-CM reversed the abnormal phosphorylation of ERK and overexpressions of MKNK2, ERBB3, MYC and DUSP5 in MAPK/ERK signaling pathway. CONCLUSIONS: HucMSCs not only ameliorated blood glucose but also protected vascular endothelium from diabetic damage, in which MAPK/ERK signaling mediated its molecular mechanism of paracrine action. Our findings provided novel knowledge of hucMSCs in the treatment of diabetes and suggested a prospective strategy for the clinical treatment of diabetic vascular complications.

Recent Insights into the Nutritional Antioxidant Therapy in Prevention and Treatment of Diabetic Vascular Complications: A Comprehensive Review.

Diabetes mellitus (DM) and DM-induced vascular complications are significant global healthcare problems, causing a decrease in patient quality of life. The main reason for the disability and mortality of patients is rapidly progressing micro-and macroangiopathies. Currently, free radical oxidation is recognized as one of the main mechanisms in the development of DM and associated complications. Under normal physiological conditions, the level of free radicals and antioxidant defense capabilities is balanced. However, imbalance occurs between the antioxidant defense system and pro-oxidants during chronic hyperglycemia and may invoke the formation of excess free radicals, leading to activation of lipid peroxidation and accumulation of highly toxic products of free radical oxidation. This is accompanied by varying degrees of insulin deficiency and insulin resistance in DM patients. Simultaneously with the activation of free radical generation, a decrease in the activity of antioxidant defense factors (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, vitamins C and E) and an acceleration of diabetic complications are seen. Therefore, we hypothesize that antioxidants may play a positive role in the treatment of DM patients to prevent DM-induced vascular complications. However, this has not been sufficiently studied. In this review, we discuss recent insights into the potential underlying mechanisms of oxidative stress-induced diabetic complications and the implications of antioxidants in mitigation of DM-induced vascular complications.

Astragaloside IV prevents endothelial dysfunction by improving oxidative stress in streptozotocin-induced diabetic mouse aortas.

Oxidative stress serves a role in endothelial dysfunction exhibited by patients with diabetes mellitus. Astragaloside IV (AS-IV) is a major active ingredient of Radix Astragali, which is considered to exhibit vasoprotective effects through unknown mechanisms. Thus, the current study was performed to investigate the protective effects of AS-IV in streptozotocin (STZ)-induced endothelial dysfunction and to explore whether antioxidant mechanisms were involved. The protective effects of AS-IV on the endothelium-dependent relaxation and contraction of aortic rings were determined by isometric tension recordings. NADPH subunits and endothelial nitric oxide synthase (eNOS) expression was identified via western blotting. Superoxide dismutase and malondialdehyde levels were assayed using ELISA. Furthermore, the generation of reactive oxygen species (ROS) and nitric oxide (NO) was detected via dihydroethidium and 4,5-diaminofluorescein diacetate staining, respectively. The results revealed that STZ-injected mice exhibited increased aortic endothelium-dependent vasoconstriction and decreased vasorelaxation to acetylcholine. However, AS-IV treatment reversed these effects. NG-nitro-L-arginine was subsequently used to completely inhibit impaired relaxation. Accordingly, impaired NO generation was restored following AS-IV treatment by increasing eNOS phosphorylation levels. Furthermore, ROS formation was also depressed following AS-IV treatment compared with that in STZ-injected mice. AS-IV also decreased the expression of various NADPH subunits, including human neutrophil cytochrome b light chain, neutrophil cytosolic factor 1, NADPH oxidase (NOX)2, NOX4 and Rac-1. The results of the current study may provide novel evidence that diabetes-induced vascular injury arises from either the inhibition of eNOS or the activation of NOX-derived ROS generation. In addition, the results warrant further investigation into the application of AS-IV treatment, leading to the improvement of oxidative stress, in patients with diabetes exhibiting endothelial dysfunction.

Exosomes: Biomarkers and Therapeutic Targets of Diabetic Vascular Complications.

Diabetic vascular complications (DVC) including macrovascular and microvascular lesions, have a significant impact on public health, and lead to increased patient mortality. Disordered intercellular cascades play a vital role in diabetic systemic vasculopathy. Exosomes participate in the abnormal signal transduction of local vascular cells and mediate the transmission of metabolic disorder signal molecules in distant organs and cells through the blood circulation. They can store different signaling molecules in the membrane structure and release them into the blood, urine, and tears. In recent years, the carrier value and therapeutic effect of exosomes derived from stem cells have garnered attention. Exosomes are not only a promising biomarker but also a potential target and tool for the treatment of DVC. This review explored changes in the production process of exosomes in the diabetic microenvironment and exosomes' early warning role in DVC from different systems and their pathological processes. On the basis of these findings, we discussed the future direction of exosomes in the treatment of DVC, and the current limitations of exosomes in DVC research.

Serum Anti-Collagen IV IgM and IgG Antibodies as Indicators of Low Vascular Turnover of Collagen IV in Patients with Long-Term Complications of Type 2 Diabetes.

Thickening of the vascular basement membrane (BM) is a fundamental structural change in the small blood vessels in diabetes. Collagen type IV (CIV) is a major component of the BMs, and monitoring the turnover of this protein in type 2 diabetes (T2D) can provide important information about the mechanisms of vascular damage. The aim of the study was through the use of non-invasive biomarkers of CIV (autoantibodies, derivative peptides, and immune complexes) to investigate vascular turnover of CIV in patients with long-term complications of T2D. We measured serum levels of these biomarkers in 59 T2D patients with micro- and/or macrovascular complications and 20 healthy controls using an ELISA. Matrix metalloproteinases-2 and -9 (MMP-2 and MMP-9) were also tested. In the T2D group, significantly lower levels of CIV markers and significantly higher levels of MMP-2 and MMP-9 were found compared to controls. A significant positive correlation was found between IgM antibody levels against CIV and MMP-2. These findings suggest that vascular metabolism of CIV is decreased in T2D with long-term complications and show that a positive linear relationship exists between MMP-2 levels and CIV turnover in the vascular wall.

Cause-specific mortality rates in patients with diabetes according to comorbid macro- and microvascular complications: BioBank Japan Cohort.

Objective: This study aimed to compare cause-specific mortality rates in patients with type 2 diabetes with and without various vascular complications. Methods: In Japanese hospitals, we followed up 30 834 patients with a mean age of 64.4 (standard deviation [SD]: 11.1) years. Patients were followed up from 2003 to 2007 for a median of 7.5 (interquartile range: 6.1-9.7) years. We calculated cause-specific mortality rates (number of deaths/1000 person-years) and confounder-adjusted hazard ratios in patients with macrovascular disease and in those with diabetic nephropathy, neuropathy and retinopathy, allowing for overlap of complications. Results: All-cause mortality rate was highest (51.4) in the nephropathy group, followed by the macrovascular disease group (45.2), the neuropathy group (39.5), the retinopathy group (38.7) and the nonvascular complication group (18.1). In the nephropathy group, morality rates of ischaemic heart, cerebrovascular, and infectious diseases and cancer were also highest among the groups. However, the cancer mortality rate was similar among the vascular complication groups. Relative to the nonvascular complication group, covariate-adjusted hazard ratios for ischaemic heart and cerebrovascular disease mortality were triple to quadruple in the macro- and microvascular complication groups. All-cause mortality rates rose exponentially according to age. Conclusion: Highest risks of all-cause, cancer, and ischaemic heart, infectious, and cerebrovascular disease mortality were determined in Japanese patients with diabetic nephropathy. Although cancer is the primary cause of death in Japanese patients with diabetes, cancer mortality rates are similar among those with and without vascular complications.

Noncoding RNAs involved in DNA methylation and histone methylation, and acetylation in diabetic vascular complications.

Diabetes is a metabolic disorder and its incidence is still increasing. Diabetic vascular complications cause major diabetic mobility and include accelerated atherosclerosis, nephropathy, retinopathy, and neuropathy. Hyperglycemia contributes to the pathogenesis of diabetic vascular complications via numerous mechanisms including the induction of oxidative stress, inflammation, metabolic alterations, and abnormal proliferation of EC and angiogenesis. In the past decade, epigenetic modifications have attracted more attention as they participate in the progression of diabetic vascular complications despite controlled glucose levels and regulate gene expression without altering the genomic sequence. DNA methylation and histone methylation, and acetylation are vital epigenetic modifications and their underlying mechanisms in diabetic vascular complication are still urgently needed to be investigated. Non-coding RNAs (nc RNAs) such as micro RNAs (miRNAs), long non-coding RNA (lncRNAs), and circular RNAs (circ RNAs) were found to exert transcriptional regulation in diabetic vascular complication. Although nc RNAs are not considered as epigenetic components, they are involved in epigenetic modifications. In this review, we summarized the investigations of non-coding RNAs involved in DNA methylation and histone methylation and acetylation. Their cross-talks might offer novel insights into the pathology of diabetic vascular complications.