Endothelial Dysfunction: Is There a Hyperglycemia-Induced Imbalance of NOX and NOS?

Effect of Nuts on Anthropometric and Glycemic Indexes and Blood Pressure in Secondary Cardiovascular Prevention: A Systematic Review and Meta-analysis of Randomized Controlled Trials

CONTEXT

Nut-enriched diets have a positive impact on cardiovascular risk factors, such as body mass, blood pressure, and fasting blood glucose. However, studies in individuals undergoing secondary cardiovascular prevention show controversial results.

OBJECTIVE

This systematic review with meta-analysis assessed the effect of nut supplementation on anthropometric, glycemic, and blood pressure indices in patients with atherosclerotic cardiovascular disease, as well as the frequency of adverse events.

DATA SOURCES

Six databases were used for the search-PubMed, Cochrane Library, EMBASE, BVS (Biblioteca Virtual da Saude), Web of Science, and ClinicalTrials.gov-until February 2023, with no language restrictions.

DATA EXTRACTION

The Cochrane Handbook for Systematic Reviews of Interventions methodology and the PICOS (Population, Intervention, Comparison, Outcome, Setting/design) strategy were used. Seven independent reviewers were involved in data extraction and resolution of disagreements. Certainty of the evidence was evaluated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system.

DATA ANALYSIS

From 5187 records identified, 6 publications containing data referring to 5 randomized clinical trials (n = 436) were included in the final analyses. The nuts evaluated were almonds, pecans, Brazil nuts, and mixed nuts, with portions that varied between 5 g and 85 g (median: 30 g/day). The intervention period varied between 6 and 12 weeks. The nuts had no effect on fasting glucose and anthropometric indices, although the certainty of the evidence for most of these outcomes was low or very low. They also had no effect on systolic (mean difference [MD]: -1.16 mmHg [95% CI, -5.68 to 3.35], I2 = 0%-moderate certainty of evidence) or diastolic (MD: 0.10 mmHg [95% CI, -2.30 to 2.51], I2 = 0%-high certainty of evidence) blood pressure. It was not possible to aggregate data on adverse events.

CONCLUSION

Nut supplementation had no effect on blood pressure, fasting glucose, or anthropometric profile in the context of atherosclerotic cardiovascular disease.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42020163456.

Cinnamic acid alleviates endothelial dysfunction and oxidative stress by targeting PPARδ in obesity and diabetes

OBJECTIVE

Cinnamic acid (CA) is a bioactive compound isolated from cinnamon. It has been demonstrated to ameliorate inflammation and metabolic diseases, which are associated with endothelial dysfunction. This study was aimed to study the potential protective effects of CA against diabetes-associated endothelial dysfunction and its underlying mechanisms.

METHODS

High-fat diet (HFD) with 60 kcal% fat was used to induce obesity/diabetes in C57BL/6 mice for 12 weeks. These diet-induced obese (DIO) mice were orally administered with CA at 20 or 40 mg/kg/day, pioglitazone (PIO) at 20 mg/kg/day or same volume of vehicle during the last 4 weeks. Isolated mouse aortic segments and primary culture rat aortic endothelial cells (RAECs) were induced with high glucose (HG) to mimic hyperglycemia and co-treated with different concentrations of CA.

RESULTS

In DIO mice, four-week administration of CA, particularly at 40 mg/kg/day, diminished the body weights, blood pressure, fasting blood glucose and plasma lipid levels, and ameliorated endothelium-dependent relaxations (EDRs) and oxidative stress in aortas. The beneficial effects of CA were comparable to the positive control group, PIO. Western blotting results indicated that CA treatment upregulated the expression of peroxisome proliferator-activated receptor delta (PPARδ), and activated nuclear factor erythroid 2-related factor 2 (Nrf2)/ heme oxygenase-1 (HO-1) and AMP-activated protein kinase (AMPK)/ protein kinase B (Akt)/ endothelial nitric oxide synthase (eNOS) signaling pathways in mouse aortas in vivo and ex vivo. HG stimulation impaired EDRs in mouse aortas and inhibited nitric oxide (NO) production but elevated reactive oxygen species (ROS) levels in RAECs. CA reversed these impairments. Importantly, PPARδ antagonist GSK0660 abolished the vasoprotective effects of CA. Molecular docking analysis suggested a high likelihood of mutual binding between CA and PPARδ.

CONCLUSION

CA protects against endothelial dysfunction and oxidative stress in diabetes and obesity by targeting PPARδ through Nrf2/HO-1 and Akt/eNOS signaling pathways.

Reviewing the path to balance: mechanisms and management of hypertension associated with targeting vascular endothelium in cancer therapy

Contemporary anticancer drugs are often accompanied by varying degrees of cardiovascular toxicity, with hypertension emerging as one of the most prevalent side effects, particularly linked to inhibitors of vascular endothelial growth factor receptor (VEGFR) and tyrosine kinase inhibitors (TKIs). Hypertension induced by cancer therapies contributes to increased cardiovascular mortality in cancer patients and survivors. Given the shared common risk factors and overlapping pathophysiological mechanisms, hypertension is also a prevalent comorbidity in this patient population. The mechanisms underlying hypertension induced by therapies targeting the vascular endothelial growth factor (VEGF) signaling pathway primarily involve reduced nitric oxide (NO) synthesis, increased endothelin-1 (ET-1) production, oxidative stress, microvascular rarefaction and dysfunction, decreased natriuresis, activation of the renin-angiotensin system (RAS), and partial endothelial cell death. Research into hypertension associated with therapies targeting the VEGF signaling pathway (VSP) could facilitate the optimization of cancer treatments, improve the evaluation and management of hypertension during targeted therapy, and help to reduce cardiovascular event rates and overall patient mortality. This review aims to provide a comprehensive summary of the current advancements in this area.

Protective effects of berbamine against arginase-1 deficiency-induced injury in human brain microvascular endothelial cells

Endothelial cell dysfunction plays a crucial role in the early development of cerebral small vessel disease (CSVD). Arginase-1 (ARG1) is expressed in endothelial cells, and its deficiency may exacerbate cerebrovascular damage by increasing reactive oxygen species (ROS) production, thereby inducing endothelial cell apoptosis. Berbamine (BBM) has shown potential in neuroprotection and cardiovascular disease prevention. This study aimed to investigate the impact of ARG1 deficiency on human brain microvascular endothelial cells and the protective effects of BBM against ARG1 deficiency-induced damage. Human brain microvascular endothelial cells (HCMEC/D3) were cultured in vitro, and ARG1 knockdown or overexpression was achieved using plasmid transfection techniques. We examined the effects of ARG1 expression levels on HCMEC/D3 cell viability, migration, apoptosis, adhesion, and angiogenesis through cellular experiments. Additionally, we explored how ARG1 expression levels influenced arginine (Arg), nitric oxide (NO), and ROS levels in HCMEC/D3 cells. The results demonstrated that ARG1 deficiency inhibited HCMEC/D3 cell viability, migration, adhesion, and angiogenesis, while promoting apoptosis and elevating Arg, NO, and ROS levels in HCMEC/D3 cells. Next, the effect of different BBM concentrations on HCMEC/D3 cell viability was assessed using the CCK-8 assay, revealing that BBM at a concentration of 5 µM had no significant impact on cell viability. Subsequently, after successfully knocking down ARG1 in HCMEC/D3 cells, the cells were treated with BBM. The results showed that BBM effectively mitigated the negative effects of ARG1 deficiency on HCMEC/D3 cell viability, migration, apoptosis, adhesion, and angiogenesis, while also reducing Arg, NO, inducible nitric oxide synthase (iNOS), and ROS levels in HCMEC/D3 cells. In conclusion, this study suggests that ARG1 deficiency may damage HCMEC/D3 cells by increasing Arg levels, leading to elevated NO and ROS levels. BBM may provide protection to ARG1-deficient HCMEC/D3 cells by reducing Arg, NO, iNOS, and ROS levels. These findings deepen our understanding of the pathogenesis of CSVD and provide a theoretical basis for the clinical application of BBM.

Unveiling the potential of bean proteins: Extraction methods, functional and structural properties, modification techniques, physiological benefits, and diverse food applications

Bean proteins, known for their sustainability, versatility, and high nutritional value, represent a valuable yet underutilized resource, receiving less industrial attention compared to soy and pea proteins. This review examines the structural and molecular characteristics, functional properties, amino acid composition, nutritional value, antinutritional factors, and digestibility of bean proteins. Their applications in various food systems, including baked goods, juice and milk substitutes, meat alternatives, edible coatings, and 3D printing inks, are discussed. The physiological benefits of bean proteins, such as antidiabetic, cardioprotective, antioxidant, and neuroprotective effects, are also presented, highlighting their potential for promoting well-being. Our review emphasizes the diversity of bean proteins and highlights ultrasound as the most effective extraction method among available techniques. Beyond their physiological benefits, bean proteins significantly enhance the structural, technological, and nutritional properties of food systems. The functionality can be further improved through various modification techniques, thereby expanding their applicability in the food industry. While studies have explored the impact of bean protein structure on their nutritional and functional properties, further research is needed to investigate advanced modification techniques and the structure-function relationship. This will enhance the utilization of bean proteins in innovative and sustainable food applications.

Oxidative stress in diabetes mellitus and its complications: From pathophysiology to therapeutic strategies

ABSTRACT

Oxidative stress due to aberrant metabolism is considered as a crucial contributor to diabetes and its complications. Hyperglycemia and hyperlipemia boost excessive reactive oxygen species generation by elevated mitochondrial respiration, increased nicotinamide adenine dinucleotide phosphate oxidase activity, and enhanced pro-oxidative processes, including protein kinase C pathways, hexosamine, polyol, and advanced glycation endproducts, which exacerbate oxidative stress. Oxidative stress plays a significant role in the onset of diabetes and its associated complications by impairing insulin production, increasing insulin resistance, maintaining hyperglycemic memory, and inducing systemic inflammation. A more profound comprehension of the molecular processes that link oxidative stress to diabetes is crucial to new preventive and therapeutic strategies. Therefore, this review discusses the mechanisms underlying how oxidative stress contributes to diabetes mellitus and its complications. We also summarize the current approaches for prevention and treatment by targeting the oxidative stress pathways in diabetes.

Microvascular effects of a mixed meal tolerance test: a model validation study

PURPOSE

Endothelial dysfunction is a pathophysiological change preceding many cardiovascular events. Measuring improvements of endothelial function is challenging when function is already optimal, which may be remediated using a physiological challenge. This study aimed to determine whether imaging assessments can detect microvascular effects of a mixed meal tolerance test (MMTT).

METHODS

Twenty healthy volunteers (age ≥45 and ≤70 years) underwent two MMTTs at the beginning (Day 1) and end (Day 84) of a twelve-week period. Imaging methods included laser speckle contrast imaging (LSCI) combined with post-occlusive reactive hyperaemia (PORH) and local thermal hyperaemia (LTH) challenges, passive leg movement ultrasonography (PLM), and sidestream dark field microscopy (SDFM). Measurements were conducted pre-MMTT and at 5 timepoints post-MMTT for PLM and SDFM and 3 timepoints post-MMTT for PORH and LTH.

RESULTS

No consistent effects of the MMTT were detected on LSCI LTH, PLM and SDFM endpoints. LSCI PORH maximum perfusion was significantly suppressed 46, 136, and 300 min post-MMTT administration on Day 1, while residual perfusion decreased significantly 46 and 136 min post-MMTT on Day 1. However, when repeated on Day 84, PORH endpoints were not significantly affected by the MMTT.

CONCLUSION

SDFM, PLM and LSCI LTH endpoints displayed high intra-subject variability and did not detect consistent effects of MMTT. LSCI PORH endpoints displayed the lowest intra-subject variability of all assessed endpoints and were affected by the MMTT on Day 1, but not on Day 84. Further standardization of methods or more robust challenges to affect vascular endpoints may be needed.

Immune and Metabolic Mechanisms of Endothelial Dysfunction

Endothelial dysfunction is a strong prognostic factor in predicting the development of cardiovascular diseases. Dysfunctional endothelium loses its homeostatic ability to regulate vascular tone and prevent overactivation of inflammation, leading to vascular dysfunction. These functions are critical for vascular homeostasis and arterial pressure control, the disruption of which may lead to hypertension. Hypertension itself can also cause endothelial dysfunction, as endothelial cells are susceptible to haemodynamic changes. Although it is unclear which of those factors appear first, they create a vicious circle further damaging multiple organs, including the heart and vessels. There are also sex-specific differences in homeostatic functions of the endothelium regarding vessel tone regulation, which may contribute to differences in arterial blood pressure between men and women. Even more importantly, there are sex-differences in the development of endothelial dysfunction and vessel remodelling. Hence, an understanding of the mechanisms of endothelial dysfunction and its contribution to pathological vascular remodelling during hypertension is of critical importance. This review addresses immunological and metabolic aspects in mechanisms of endothelial dysfunction and the resulting mechanisms in vascular remodelling with respect to arterial hypertension, including the potential role of sex-specific differences.

Multi-omics analysis of the lipid-regulating effects of metformin in a glucose concentration-dependent manner in macrophage-derived foam cells

Metformin has a long history of clinical application and has been shown to have outstanding ability in lowering glucose. Recent advances have further revealed its broad modulatory ability beyond glucose-lowering, expanding the scope of metformin applications. Metformin has now been applied as a viable lipid-lowering strategy in non-hyperglycemic obese patients. However, the benefits and underlying pharmacological mechanisms of metformin administration in non-hyperglycemic populations remain to be explained. Our study aimed to systematically investigate the differences in the lipid-lowering function and pharmacological mechanisms of metformin in high- and low-sugar conditions to facilitate the development of individualized metformin use regimens for different clinical patients. We constructed macrophage-derived foam cell models in vitro for subsequent analysis. ORO results showed that metformin significantly reduced lipid accumulation in macrophages in both high and low glucose environments, but the lipid decline was higher in the high glucose environment. By mutual validation and joint analysis of transcriptomics and metabolomics, significant differences in metformin transcriptional and metabolic patterns existed among high and normal glucose environments. The significant alterations of genes such as DGKA, LPL, DGAT2 and lipid metabolites such as LysPA and LysPC partially explained the glucose-dependent pharmacological function of metformin. In conclusion, our study confirmed that the lipid-lowering effect of metformin depends on the extracellular glucose concentration, and systematically studied the molecular mechanism of metformin in different glycemic environments, which provides a certain reference value for the subsequent in-depth study and clinical application.

Cardioprotection and neurobehavioral impact of swimming training in ovariectomized rats

Cardiovascular (CV) disease is the major cause of mortality. Estrogens (E) exert multiple CV and neuroprotective effects. During menopause, CV and cognitive pathologies increase dramatically. At present, it is known that E exert many of their beneficial effects through the G protein-coupled estrogen receptor (GPER). Exercise reduces the risk of developing CV diseases. Sodium/proton exchanger (NHE-1) is overexpressed in ovariectomized (OVX) rats, probably due to the increase in reactive oxidative species (ROS). Insulin-like growth factor 1 (IGF-1), the main humoral mediator of exercise, inhibits the NHE-1. We aim to explore the subcellular mechanisms involved in the heart and brain impact of physiological exercise in OVX rats. We speculate that physical training, via IGF-1, prevents the increase in ROS, improving heart and brain physiological functions during menopause. Exercise diminished cardiac ROS production and increased catalase (CAT) activity in OVX rats. In concordance, IGF-1 treatment reduces brain ROS, surely contributing to the improvement in brain behavior. Moreover, the aerobic routine was able to prevent, and IGF-1 therapy to revert, NHE-1 hyperactivity in OVX rats. Finally, our results confirm the proposed signaling pathway as IGF-1/PI3K-AKT/NO. Surprisingly, GPER inhibitor (G36) was able to abolish the IGF-1 effect, suggesting that directly or indirectly GPER is part of the IGF-1 pathway. We propose that IGF-1 is the main responsible for the protective effect of aerobic training both in the heart and brain in OVX rats. Moreover, we showed that not only it is possible to prevent but also to revert the menopause-induced NHE-1 hyperactivity by exercise/IGF-1 cascade.

Endothelial KLF11 is a novel protector against diabetic atherosclerosis

BACKGROUND

Atherosclerotic cardiovascular diseases remain the leading cause of mortality in diabetic patients, with endothelial cell (EC) dysfunction serving as the initiating step of atherosclerosis, which is exacerbated in diabetes. Krüppel-like factor 11 (KLF11), known for its missense mutations leading to the development of diabetes in humans, has also been identified as a novel protector of vascular homeostasis. However, its role in diabetic atherosclerosis remains unexplored.

METHODS

Diabetic atherosclerosis was induced in both EC-specific KLF11 transgenic and knockout mice in the Ldlr-/- background by feeding a diabetogenic diet with cholesterol (DDC). Single-cell RNA sequencing (scRNA-seq) was utilized to profile EC dysfunction in diabetic atherosclerosis. Additionally, gain- and loss-of-function experiments were conducted to investigate the role of KLF11 in hyperglycemia-induced endothelial cell dysfunction.

RESULTS

We found that endothelial KLF11 deficiency significantly accelerates atherogenesis under diabetic conditions, whereas KLF11 overexpression remarkably inhibits it. scRNA-seq profiling demonstrates that loss of KLF11 increases endothelial-to-mesenchymal transition (EndMT) during atherogenesis under diabetic conditions. Utilizing gain- and loss-of-function approaches, our in vitro study reveals that KLF11 significantly inhibits EC inflammatory activation and TXNIP-induced EC oxidative stress, as well as Notch1/Snail-mediated EndMT under high glucose exposure.

CONCLUSION

Our study demonstrates that endothelial KLF11 is an endogenous protective factor against diabetic atherosclerosis. These findings indicate that manipulating KLF11 could be a promising approach for developing novel therapies for diabetes-related cardiovascular complications.

Association between blood glucose level trajectories and 30-day mortality risk in patients with acute ischemic stroke: analysis of the MIMIC database 2001-2019

BACKGROUND

Hyperglycemia is one of the most common comorbidities in patients with acute ischemic stroke (AIS). This study aimed to assess the impact of short-term longitudinal blood glucose level change trajectories on the 30-day mortality risk in patients with AIS.

METHODS

Data for AIS patients were obtained from the 2001-2019 Medical Information Mart for Intensive Care (MIMIC) database. The latent growth mixture modeling (LGMM) was utilized to classify a patient's blood glucose level trajectory within 24 h of admission. Cox regression analyses were applied to examine the relationship between blood glucose levels at admission and blood glucose level trajectories and the risk of 30-day mortality in patients with AIS.

RESULTS

A total of 2,432 patients with AIS were included in this retrospective cohort study, with 30-day mortality occurring in 574 (23.60%) patients. The median glucose levels of all patients were 136.00 (110.00, 178.00) mg/dL. Four blood glucose level trajectories were identified: low level-stable trend (type 1), moderate level-stable trend (type 2), high level-decreasing-increasing trend (type 3), and moderate level-increasing-decreasing trend (type 4). Type 2 blood glucose level trajectory was associated with an increased risk of 30-day mortality compared with type 1 blood glucose level trajectory [hazard ratio (HR) = 1.28, 95% confidence interval (CI): 1.03-1.59), but there were no significant associations between type 3 (HR = 1.16, 95%CI: 0.77-1.74) and type 4 (HR = 1.44, 95%CI: 0.84-2.45) trajectories and 30-day mortality risk. Subgroup analysis demonstrated that the association between type 2 trajectory and 30-day mortality risk was observed in patients aged ≥ 65 years (HR = 1.37, 95%CI: 1.05-1.79), female (HR = 1.42, 95%CI: 1.05-1.94), with (HR = 1.44, 95%CI: 1.02-2.02) or without (HR = 1.42, 95%CI: 1.01-1.99) diabetes, and not using insulin (HR = 2.80, 95%CI: 1.43-5.49).

CONCLUSION

AIS patients with consistently high blood glucose levels within 24 h of admission increased the risk of 30-day mortality.

Vasodilator reactive oxygen species ameliorate perturbed myocardial oxygen delivery in exercising swine with multiple comorbidities

Multiple common cardiovascular comorbidities produce coronary microvascular dysfunction. We previously observed in swine that a combination of diabetes mellitus (DM), high fat diet (HFD) and chronic kidney disease (CKD) induced systemic inflammation, increased oxidative stress and produced coronary endothelial dysfunction, altering control of coronary microvascular tone via loss of NO bioavailability, which was associated with an increase in circulating endothelin (ET). In the present study, we tested the hypotheses that (1) ROS scavenging and (2) ETA+B-receptor blockade improve myocardial oxygen delivery in the same female swine model. Healthy female swine on normal pig chow served as controls (Normal). Five months after induction of DM (streptozotocin, 3 × 50 mg kg-1 i.v.), hypercholesterolemia (HFD) and CKD (renal embolization), swine were chronically instrumented and studied at rest and during exercise. Sustained hyperglycemia, hypercholesterolemia and renal dysfunction were accompanied by systemic inflammation and oxidative stress. In vivo ROS scavenging (TEMPOL + MPG) reduced myocardial oxygen delivery in DM + HFD + CKD swine, suggestive of a vasodilator influence of endogenous ROS, while it had no effect in Normal swine. In vitro wire myography revealed a vasodilator role for hydrogen peroxide (H2O2) in isolated small coronary artery segments from DM + HFD + CKD, but not Normal swine. Increased catalase activity and ceramide production in left ventricular myocardial tissue of DM + HFD + CKD swine further suggest that increased H2O2 acts as vasodilator ROS in the coronary microvasculature. Despite elevated ET-1 plasma levels in DM + HFD + CKD swine, ETA+B blockade did not affect myocardial oxygen delivery in Normal or DM + HFD + CKD swine. In conclusion, loss of NO bioavailability due to 5 months exposure to multiple comorbidities is partially compensated by increased H2O2-mediated coronary vasodilation.

Acute endothelial, blood pressure, and glycemic responses after aerobic sessions in type-2 diabetic with hypertension: A double-blinded randomized study

OBJECTIVES

To compare the acute response of moderate intensity continuous exercise (MICE) vs moderate intensity interval exercise (MIIE) on endothelial function, post-exercise hypotension (PEH), and glycemia in type 2 diabetes (T2DM) with hypertension.

METHODS

Twelve T2DM (aged 52.8 ± 3.8 years old) patients with hypertension underwent a randomized cross-over study following isocaloric (200 kcal) protocols: (i) MICE: walk-jogging at 50% of VO2peak, (ii) MIIE session: walking - jogging (stimulus/recovery - 3:3 min each) at 60% of VO2peak followed by recovery at 40% of VO2peak, and (iii) control (CON): lying quietly in a supine position for 30 min. A generalized estimating equation was utilized to verify possible differences over time × session.

RESULTS

The %FMD (Baseline: 3.59 ± 1.58 vs. 30 min: 6.73 ± 4.34) and the absolute FMD changed after MIIE (Baseline: 0.16 ± 0.10 vs. 30 min: 0.17 ± 0.14). Only absolute FMD changed after MIIE (Baseline: 0.14 ± 0.07 vs. 30 min: 0.16 ± 0.07). Besides, MIIE at 30 min provides higher absolute FMD values when compared to baseline from MICE and baseline, 30 min, and 60 min from control. Regarding blood pressure, no PEH statistical main effect was found. Finally, the glycemia changed at baseline vs. 30 min and 60 min after MIIE (210.5 ± 9.4 vs. 127.6 ± 10.0 and 120 ± 8.9), MICE (219.5 ± 12.7 vs. 125.2 ± 12.0 and 118.2 ± 11.6), and control sessions (215.9 ± 11.8 vs. 187.4 ± 11.2 and 172.6 ± 11.3 mg/dL, p < 0.05). However, MIIE and MICE showed higher decreases compared to the control.

CONCLUSIONS

MIIE and MICE sessions are similar and effective exercise strategies to induce changes in endothelial function and glycemic responses in type-2 diabetics with hypertension.

Dengue fever in hyperglycemic patients: an emerging public health concern demanding eyes on the effective management strategies

Background and aims

Hyperglycemia, also known as diabetes, is a metabolic disorder characterized by elevated levels of glucose in the bloodstream. It can lead to the prolonged dysfunction, injury, and deterioration of several organs. In addition, dengue is a viral illness transmitted by mosquitoes that has reached epidemic proportions worldwide. In this article, we focused on the severity of comorbidities, difficulties in managing them, and preventive measures meant to lessen the risks associated with comorbidities in diabetic patients with dengue infection.

Methods

We explored a number of databases, including PubMed, Scopus, Embase, Web of Science, Google Scholar, and the Cochrane Library, for this review article using various related keywords.

Results

The findings of this review article indicate that elderly dengue patients with diabetes should be admitted to the hospital for close observation and early management using fluid therapy. An observed association exists between dengue hemorrhagic fever (DHF) and diabetes, indicating a possible consequence in this specific group. Additionally, patients with diabetes who contract dengue show elevated levels of inflammatory markers. Diabetes mellitus deteriorates the immune system, which exacerbates the progression of dengue fever. Cutting-edge technology and scientific research may assist in addressing the challenges that diabetes and dengue viruses pose in low- and middle-income countries. Implementing innovative diabetic care management is essential to ensuring consistency of care, improving a healthy lifestyle, and lowering patient risk factors and comorbidities.

Conclusion

Dengue fever has spread to epidemic levels throughout the world. Inflammatory markers increase and the prevalence of DHF is greater in diabetes individuals with dengue infection. Given the continued growth of dengue in Asian nations, it is imperative that we concentrate our efforts and resources on providing more precise and effective treatment for this emerging issue.

Endothelial dysfunction: mechanisms and contribution to diseases

The endothelium, lining the inner surface of blood vessels and spanning approximately 3 m2, serves as the largest organ in the body. Comprised of endothelial cells, the endothelium interacts with other bodily components including the bloodstream, circulating cells, and the lymphatic system. Functionally, the endothelium primarily synchronizes vascular tone (by balancing vasodilation and vasoconstriction) and prevents vascular inflammation and pathologies. Consequently, endothelial dysfunction disrupts vascular homeostasis, leading to vascular injuries and diseases such as cardiovascular, cerebral, and metabolic diseases. In this opinion/perspective piece, we explore the recently identified mechanisms of endothelial dysfunction across various disease subsets and critically evaluate the strengths and limitations of current therapeutic interventions at the pre-clinical level.

The Pathophysiological Associations Between Obesity, NAFLD, and Atherosclerotic Cardiovascular Diseases

Obesity, non-alcoholic fatty liver disease (NAFLD), and atherosclerotic cardiovascular diseases are common and growing public health concerns. Previous epidemiological studies unfolded the robust correlation between obesity, NAFLD, and atherosclerotic cardiovascular diseases. Obesity is a well-known risk factor for NAFLD, and both of them can markedly increase the odds of atherosclerotic cardiovascular diseases. On the other hand, significant weight loss achieved by lifestyle modification, bariatric surgery, or medications, such as semaglutide, can concomitantly improve NAFLD and atherosclerotic cardiovascular diseases. Therefore, certain pathophysiological links are involved in the development of NAFLD in obesity, and atherosclerotic cardiovascular diseases in obesity and NAFLD. Moreover, recent studies indicated that simultaneously targeting several mechanisms by tirzepatide and retatrutide leads to greater weight loss and markedly improves the complications of metabolic syndrome. These findings remind the importance of a mechanistic viewpoint for breaking the association between obesity, NAFLD, and atherosclerotic cardiovascular diseases. In this review article, we mainly focus on shared pathophysiological mechanisms, including insulin resistance, dyslipidemia, GLP1 signaling, inflammation, oxidative stress, mitochondrial dysfunction, gut dysbiosis, renin-angiotensin-aldosterone system (RAAS) overactivity, and endothelial dysfunction. Most of these pathophysiological alterations are primarily initiated by obesity. The development of NAFLD further exacerbates these molecular and cellular alterations, leading to atherosclerotic cardiovascular disease development or progression as the final manifestation of molecular perturbation. A better insight into these mechanisms makes it feasible to develop new multi-target approaches to simultaneously unhinge the deleterious chain of events linking obesity and NAFLD to atherosclerotic cardiovascular diseases.

Lipid emulsion attenuates vasodilation by decreasing intracellular calcium and nitric oxide in vascular endothelial cells

Lipid emulsion (LE), a widely used parenteral nutrition, exhibits a well-documented ability to reverse the vasodilatory effects induced by acetylcholine in blood vessels. However, the specific mechanisms underlying this action are not yet fully understood. This study aimed to elucidate the mechanism by which LE reverses vasodilation in vitro through dose-response curve experiments, calcium imaging, and fluorescence assays. The results revealed a significant attenuation of acetylcholine (Ach)-induced vasodilation in rat thoracic aortic rings following LE exposure. In human aortic endothelial cells, pretreatment with LE significantly suppressed ATP-induced calcium elevation. This suppression persisted even after elimination of extracellular calcium with a calcium chelator. Moreover, LE pre-exposure reduced the intracellular calcium concentration ([Ca2+]i) elevation in endothelial cells following cyclopiazonic acid (CPA) treatment, suggesting enhanced endoplasmic reticulum (ER) calcium reuptake. Additionally, nitric oxide (NO) fluorescence assays showed a decrease in NO production upon ATP stimulation post-LE pretreatment of endothelial cells. Taken together, these results indicate that the reversal of vasodilation by LE may involve enhanced ER calcium uptake, leading to a reduction in intracellular calcium concentration and suppression of NO (key vasodilatory agent) synthesis.

Hyperglycemia and Venous Thromboembolism

Patients with diabetes mellitus (DM) have chronically increased blood glucose and multiple physiologic alterations that place them at elevated risk for vascular disease. Traditionally, this vascular risk has mainly referred to chronic atherosclerosis and embolic arterial disease. Retrospective studies have suggested an increased risk of a pulmonary embolism (PE) and deep vein thrombosis (DVT), collectively termed venous thromboembolism (VTE), in patients with DM, but this association has been difficult to demonstrate with comorbidities such as obesity in meta-analysis. Clinical studies have demonstrated worse outcomes for patients with DM who suffer from VTE. In vitro studies show multiple physiologic abnormalities with chronic inflammation, endothelial dysfunction, dysfunction in the coagulation cascade, as well as other changes that drive a vicious cycle of hypercoagulability. Aggressive medical management of DM can improve vascular outcomes, and some anti-hyperglycemic therapies may modify VTE risk as well. Anticoagulation strategies are similar for patients with DM, but with some added considerations, such as high rates of comorbid renal dysfunction. More research is needed to definitively categorize DM as a risk factor for VTE and elucidate specific therapeutic strategies.

Insulin-based or non-insulin-based insulin resistance indicators and risk of long-term cardiovascular and all-cause mortality in the general population: A 25-year cohort study

OBJECTIVE

Although insulin resistance (IR) has been recognized to be a causal component in various diseases, current information on the relationship between IR and long-term mortality in the general population is limited and conclusions varied among different IR indicators and different populations. We aimed to assess associations between different measurements of IR with long-term all-cause mortality and cardiovascular mortality risk for the general population.

RESEARCH DESIGN AND METHODS

We included 13,909 individuals from the Third National Health and Nutrition Examination Survey. Mortality was identified via National Death Index information until December 31, 2019. IR was measured using fasting insulin, homeostasis model assessment of IR (HOMA-IR), homeostasis model assessment of β-cell function, quantitative insulin sensitivity check index (QUICKI), insulin-to-glucose ratio (IGR), triglyceride glucose (TyG) index, TyG-body mass index (TyG-BMI), and hypertriglyceridemic-waist phenotype.

RESULTS

During median 25-year follow-up, 5,306 all-cause mortality events occurred. After multivariate adjustment, variables significantly associated with elevated all-cause mortality risk were (hazard ratio [95 % confidence interval]): higher insulin (1.07 [1.02;1.13]); HOMA-IR (1.08 [1.03;1.13]); IGR (1.05 [1.00;1.11]); TyG (1.07 [1.00;1.14]); TyG-BMI (1.24 [1.02;1.51]); lower QUICKI (0.91 [0.86-0.96]). After stratification by diabetes status, higher insulin, HOMA-IR, TyG-BMI and lower QUICKI were significantly associated with increased risk of all-cause mortality in both diabetes and non-diabetes populations (all P for interaction > 0.05). Higher TyG (adjusted HR 1.17 [1.09;1.26], P for interaction = 0.018) and hypertriglyceridemic-waist phenotype (adjusted HR 1.26 [1.08;1.46], P for interaction = 0.047) were significantly associated with increased risk of all-cause mortality in patients with diabetes, however, these associations could not be seen in people without diabetes. Similar results were observed between the above-mentioned IR indicators and cardiovascular death.

CONCLUSIONS

Fasting insulin, HOMA-IR, TyG-BMI, and QUICKI may indicate mortality risk in diabetes and non-diabetes populations, with TyG and the hypertriglyceridemic-waist phenotype showing particular relevance for individuals with diabetes. Further studies are needed to validate these findings and determine their broader applicability.

Effect of aortic smooth muscle BK channels on mediating chronic intermittent hypoxia-induced vascular dysfunction

Chronic intermittent hypoxia (CIH) can lead to vascular dysfunction and increase the risk of cardiovascular diseases, cerebrovascular diseases, and arterial diseases. Nevertheless, mechanisms underlying CIH-induced vascular dysfunction remain unclear. Herein, this study analyzed the role of aortic smooth muscle calciumactivated potassium (BK) channels in CIH-induced vascular dysfunction. CIH models were established in rats and rat aortic smooth muscle cells (RASMCs). Hemodynamic parameters such as mean blood pressure (MBP), diastolic blood pressure (DBP), and systolic blood pressure (SBP) were measured in rats, along with an assessment of vascular tone. NO and ET-1 levels were detected in rat serum, and the levels of ET-1, NO, eNOS, p-eNOS, oxidative stress markers (ROS and MDA), and inflammatory factors (IL-6 and TNF-α) were tested in aortic tissues. The Ca2+ concentration in RASMCs was investigated. The activity of BK channels (BKα and BKβ) was evaluated in aortic tissues and RASMCs. SBP, DBP, and MBP were elevated in CIH-treated rats, along with endothelial dysfunction, cellular edema and partial detachment of endothelial cells. BK channel activity was decreased in CIH-treated rats and RASMCs. BK channel activation increased eNOS, p-eNOS, and NO levels while lowering ET-1, ROS, MDA, IL-6, and TNF-α levels in CIH-treated rats. Ca2+ concentration increased in RASMCs following CIH modeling, which was reversed by BK channel activation. BK channel inhibitor (Iberiotoxin) exacerbated CIH-induced vascular disorders and endothelial dysfunction. BK channel activation promoted vasorelaxation while suppressing vascular endothelial dysfunction, inflammation, and oxidative stress, thereby indirectly improving CIH-induced vascular dysfunction.

Effects of Single Low-Carbohydrate, High-Fat Meal Consumption on Postprandial Lipemia and Markers of Endothelial Dysfunction: A Systematic Review of Current Evidence

CONTEXT

Postprandial lipemia (PPL) is associated with increased risk of endothelial dysfunction (ED), a precursor of atherosclerotic cardiovascular disease (ASCVD). The effects of low-carbohydrate, high-fat (LCHF) diets on ASCVD risk are uncertain; therefore, gaining a greater understanding of LCHF meals on PPL may provide valuable insights.

OBJECTIVE

The current systematic review investigated the effects of single LCHF meal consumption on PPL and markers of ED.

DATA SOURCES

CINAHL Plus, PubMed, Web of Science, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched for key terms related to endothelial function, cardiovascular disease, glycemia, lipemia, and the postprandial state with no restriction on date.

DATA EXTRACTION

Full-text articles were independently screened by 2 reviewers, of which 16 studies were eligible to be included in the current review. All trials reported a minimum analysis of postprandial triglycerides (PPTG) following consumption of an LCHF meal (<26% of energy as carbohydrate). Results were reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

DATA ANALYSIS

Single-meal macronutrient composition was found to play a key role in determining postprandial lipid and lipoprotein responses up to 8 hours post-meal. Consumption of LCHF meals increased PPTG and may contribute to ED via reduced flow-mediated dilation and increased oxidative stress; however, energy and macronutrient composition varied considerably between studies.

CONCLUSION

Consumption of an LCHF meal had a negative impact on PPL based on some, but not all, single-meal studies; therefore, the contribution of LCHF meals to cardiometabolic health outcomes remains unclear. Further research is needed on specific categories of LCHF diets to establish a causal relationship between postprandial modulation of lipids/lipoproteins and impaired vascular endothelial function.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD 42023398774.

Catecholamine induces endothelial dysfunction via Angiotensin II and intermediate conductance calcium activated potassium channel

Endothelial dysfunction contributes to the pathogenesis of Takotsubo syndrome (TTS). However, the exact mechanism underlying endothelial dysfunction in the setting of TTS has not been completely clarified. This study aims to investigate the roles of angiotensin II (Ang II) and intermediate-conductance Ca2+-activated K+ (SK4) channels in catecholamine-induced endothelial dysfunction. Human cardiac microvascular endothelial cells (HCMECs) were exposed to 100 µM epinephrine (Epi), mimicking the setting of TTS. Epi treatment increased the ET-1 concentration and reduced NO levels in HCMECs. Importantly, the effects of Epi were found to be mitigated in the presence of Ang II receptor blockers. Furthermore, Ang II mimicked Epi effects on ET-1 and NO production. Additionally, Ang II inhibited tube formation and increased cell apoptosis. The effects of Ang II could be reversed by an SK4 activator NS309 and mimicked by an SK4 channel blocker TRAM-34. Ang II also inhibited the SK4 channel current (ISK4) without affecting its expression level. Ang II could depolarize the cell membrane potential. Ang II promoted ROS release and reduced protein kinase A (PKA) expression. A ROS blocker prevented Ang II effect on ISK4. The PKA activator Sp-8-Br-cAMPS increased SK4 channel currents. Epinephrine enhanced the activity of ACE by activating the α1 receptor/Gq/PKC signal pathway, thereby promoting the secretion of Ang II. The study suggested that high-level catecholamine can increase Ang II release from endothelial cells by α1 receptors/Gq/PKC signal pathway. Ang II can inhibit SK4 channel current by increasing ROS generation and reducing PKA expression, thereby contributing to endothelial dysfunction.

The Role of Estrogen across Multiple Disease Mechanisms

Estrogen is a significant hormone that is involved in a multitude of physiological and pathological processes. In addition to its pivotal role in the reproductive system, estrogen is also implicated in the pathogenesis of a multitude of diseases. Nevertheless, previous research on the role of estrogen in a multitude of diseases, including Alzheimer's disease, depression, cardiovascular disease, diabetes, osteoporosis, gastrointestinal diseases, and estrogen-dependent cancers, has concentrated on a single disease area, resulting in a lack of comprehensive understanding of cross-disease mechanisms. This has brought some challenges to the current treatment methods for these diseases, because estrogen as a potential therapeutic tool has not yet fully developed its potential. Therefore, this review aims to comprehensively explore the mechanism of estrogen in these seven types of diseases. The objective of this study is to describe the relationship between each disease and estrogen, including the ways in which estrogen participates in regulating disease mechanisms, and to outline the efficacy of estrogen in treating these diseases in clinical practice. By studying the role of estrogen in a variety of disease mechanisms, it is hoped that a more accurate theoretical basis and clinical guidance for future treatment strategies will be provided, thus promoting the effective management and treatment of these diseases.

Impact of Endurance Exercise Training on Biomarkers of Aortic Endothelial Damage in Diabetic Rats

Given the heightened risk of diabetes-related cardiovascular events associated with inactivity, this study investigates the molecular mechanisms of vascular damage in streptozotocin (STZ)-induced diabetic rats. The aim is to elucidate the impact of different exercises (interval and continuous training) and metformin on biochemical parameters, aortic injury, oxidative stress, and inflammation to provide insights into potential therapeutic interventions for diabetes-associated vascular complications. Male Wistar rats were administered a single dose of STZ (60 mg/kg) to induce diabetes. Diabetic rats underwent either interval training or continuous training (40 min/day, 5 days/week, 6 weeks), received metformin (300 mg/kg), or a combination of metformin and exercise. After 6 weeks, biochemical parameters in serum and oxidative stress markers and mRNA expression of endothelial nitric oxide synthase (eNOS), lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), and intercellular adhesion molecule-1 (ICAM-1) in aorta tissue were assessed. Serum levels of fasting blood sugar (FBS), triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL), TG/HDL, TC/HDL, and LDL/HDL ratios were significantly reduced in all treatment groups compared to the diabetes group. Both types of exercises, metformin, and exercise+metformin combinations, significantly reduced oxidative stress by decreasing malondialdehyde (MDA) and enhancing the antioxidant status in the aortic tissue compared to the diabetic group. In addition, in exercise groups, metformin, and combination groups, the expression of eNOS was significantly elevated, while LOX-1 and ICAM-1 expression significantly decreased compared to the diabetic group. In most cases, the combination of exercise and metformin (especially interval training) was more effective than exercise alone. It seems that exercise along with taking metformin can be considered as a therapeutic method by improving hyperglycemia and hyperlipidemia and reducing oxidative stress and vascular inflammatory responses, leading to ameliorating biomarkers function related to endothelial damage in experimental diabetes conditions.

Exploring the role of Müller cells-derived exosomes in diabetic retinopathy

Exosomes are nanosized vesicles that have been reported as cargo-delivering vehicles between cells. Müller cells play a crucial role in the pathogenesis of diabetic retinopathy (DR). Activated Müller cells in the diabetic retina mediate disruption of barrier integrity and neovascularization. Endothelial cells constitute the inner blood-retinal barrier (BRB). Herein, we aim to evaluate the effect of Müller cell-derived exosomes on endothelial cell viability and barrier function under normal and hyperglycemic conditions. Müller cell-derived exosomes were isolated and characterized using Western blotting, nanoparticle tracking, and electron microscopy. The uptake of Müller cells-derived exosomes by the human retinal endothelial cells (HRECs) was monitored by labeling exosomes with PKH67. Endothelial cell vitality after treatment by exosomes under normo- and hypoglycemic conditions was checked by MTT assay and Western blot for apoptotic proteins. The barrier function of HRECs was evaluated by analysis of ZO-1 and transcellular electrical resistance (TER) using ECIS. Additionally, intracellular Ca+2 in HRECs was assessed by spectrofluorimetry. Analysis of the isolated exosomes showed a non-significant change in the number of exosomes isolated from both normal and hyperglycemic condition media, however, the average size of exosomes isolated from the hyperglycemic group showed a significant rise when compared to that of the normoglycemic group. Müller cells derived exosomes from hyperglycemic condition media markedly reduced HRECs cell count, increased caspase-3 and Annexin V, decreased ZO-1 levels and TER, and increased intracellular Ca+ when compared to other groups. However, treatment of HRECs under hyperglycemia with normo-glycemic Müller cells-derived exosomes significantly decreased cell death, preserved cellular integrity and barrier function, and reduced intracellular Ca+2. Collectively, Müller cell-derived exosomes play a remarkable role in the pathological changes associated with hyperglycemia-induced inner barrier dysfunction in DR. Further in vivo research will help in understanding the role of exosomes as therapeutic targets and/or delivery systems for DR.

Resilience to diabetic retinopathy

Chronic elevation of blood glucose at first causes relatively minor changes to the neural and vascular components of the retina. As the duration of hyperglycemia persists, the nature and extent of damage increases and becomes readily detectable. While this second, overt manifestation of diabetic retinopathy (DR) has been studied extensively, what prevents maximal damage from the very start of hyperglycemia remains largely unexplored. Recent studies indicate that diabetes (DM) engages mitochondria-based defense during the retinopathy-resistant phase, and thereby enables the retina to remain healthy in the face of hyperglycemia. Such resilience is transient, and its deterioration results in progressive accumulation of retinal damage. The concepts that co-emerge with these discoveries set the stage for novel intellectual and therapeutic opportunities within the DR field. Identification of biomarkers and mediators of protection from DM-mediated damage will enable development of resilience-based therapies that will indefinitely delay the onset of DR.

Duodenal-jejunal bypass surgery activates eNOS and enhances antioxidant system by activating AMPK pathway to improve heart oxidative stress in diabetic cardiomyopathy rats

BACKGROUND

Diabetic cardiomyopathy is a serious complication of obesity with type 2 diabetes and is a major cause of mortality. Metabolic surgery, such as duodenal-jejunal bypass (DJB), can effectively improve diabetic cardiomyopathy; however, the underlying mechanisms remain elusive. Oxidative stress is one of the pivotal mechanisms of diabetic cardiomyopathy. Our objective was to investigate the effect and potential mechanisms of DJB on oxidative stress in the heart of diabetic cardiomyopathy rats.

METHODS

High-fat diet combined with intraperitoneal injection of streptozotocin was used to establish diabetic cardiomyopathy rats. DJB was performed on diabetic cardiomyopathy rats, and high glucose and palmitate were used to simulate diabetic cardiomyopathy in H9C2 cells in vitro. Sera from different groups of rats were used for experiments in vivo and in vitro.

RESULTS

DJB effectively improved oxidative stress and activated the adenosine monophosphate (AMP)-activated protein kinase (AMPK) pathway to increase endothelial nitric oxide synthase (eNOS) phosphorylation level and the expression of antioxidative system-related proteins and genes in the heart of diabetic cardiomyopathy rats. AMPK agonists and serum from DJB rats activated the AMPK pathway to increase eNOS phosphorylation level and the expression of antioxidative system-related proteins and genes and decreased the content of reactive oxygen species in H9C2 cells, but this improvement was almost eliminated by the addition of AMPK inhibitors.

CONCLUSIONS

DJB activates eNOS and enhances the antioxidant system by activating the AMPK pathway-and not solely by improving blood glucose-to improve oxidative stress in the heart of diabetic cardiomyopathy rats.

Activation of PPARδ in bone marrow endothelial progenitor cells improves their hematopoiesis-supporting ability after myelosuppressive injury

Dysfunctional bone marrow (BM) endothelial progenitor cells (EPCs) with high levels of reactive oxygen species (ROS) are responsible for defective hematopoiesis in poor graft function (PGF) patients with acute leukemia or myelodysplastic neoplasms post-allotransplant. However, the underlying mechanism by which BM EPCs regulate their intracellular ROS levels and the capacity to support hematopoiesis have not been well clarified. Herein, we demonstrated decreased levels of peroxisome proliferator-activated receptor delta (PPARδ), a lipid-activated nuclear receptor, in BM EPCs of PGF patients compared with those with good graft function (GGF). In vitro assays further identified that PPARδ knockdown contributed to reduced and dysfunctional BM EPCs, characterized by the impaired ability to support hematopoiesis, which were restored by PPARδ overexpression. Moreover, GW501516, an agonist of PPARδ, repaired the damaged BM EPCs triggered by 5-fluorouracil (5FU) in vitro and in vivo. Clinically, activation of PPARδ by GW501516 benefited the damaged BM EPCs from PGF patients or acute leukemia patients in complete remission (CR) post-chemotherapy. Mechanistically, we found that increased expression of NADPH oxidases (NOXs), the main ROS-generating enzymes, may lead to elevated ROS level in BM EPCs, and insufficient PPARδ may trigger BM EPC damage via ROS/p53 pathway. Collectively, we found that defective PPARδ contributes to BM EPC dysfunction, whereas activation of PPARδ in BM EPCs improves their hematopoiesis-supporting ability after myelosuppressive therapy, which may provide a potential therapeutic target not only for patients with leukemia but also for those with other cancers.

New Developments in Pharmacological Treatment of Obesity and Type 2 Diabetes-Beyond and within GLP-1 Receptor Agonists

Guidelines for the management of obesity and type 2 diabetes (T2DM) emphasize the importance of lifestyle changes, including a reduced-calorie diet and increased physical activity. However, for many people, these changes can be difficult to maintain over the long term. Medication options are already available to treat obesity, which can help reduce appetite and/or reduce caloric intake. Incretin-based peptides exert their effect through G-protein-coupled receptors, the receptors for glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), and glucagon peptide hormones are important regulators of insulin secretion and energy metabolism. Understanding the role of intercellular signaling pathways and inflammatory processes is essential for the development of effective pharmacological agents in obesity. GLP-1 receptor agonists have been successfully used, but it is assumed that their effectiveness may be limited by desensitization and downregulation of the target receptor. A growing number of new agents acting on incretin hormones are becoming available for everyday clinical practice, including oral GLP-1 receptor agonists, the dual GLP-1/GIP receptor agonist tirzepatide, and other dual and triple GLP-1/GIP/glucagon receptor agonists, which may show further significant therapeutic potential. This narrative review summarizes the therapeutic effects of different incretin hormones and presents future prospects in the treatment of T2DM and obesity.

Citronellal improves endothelial dysfunction by affecting the stability of the GCH1 protein

Endothelial dysfunction (ED) serves as the pathological basis for various cardiovascular diseases. Guanosine triphosphate cyclopyrrolone 1 (GCH1) emerges as a pivotal protein in sustaining nitric oxide (NO) production within endothelial cells, yet it undergoes degradation under oxidative stress, contributing to endothelial cell dysfunction. Citronellal (CT), a monoterpenoid, has been shown to ameliorate endothelial dysfunction induced by in atherosclerosis rats. However, whether CT can inhibit the degradation of GCH1 protein is not clear. It has been reported that ubiquitination may play a crucial role in regulating GCH1 protein levels and activities. However, the specific E3 ligase for GCH1 and the molecular mechanism of GCH1 ubiquitination remain unclear. Using data-base exploration analysis, we find that the levels of the E3 ligase Smad-ubiquitination regulatory factor 2 (Smurf2) negatively correlate with those of GCH1 in vascular tissues and HUVECs. We observe that Smurf2 interacts with GCH1 and promotes its degradation via the proteasome pathway. Interestingly, ectopic Smurf2 expression not only decreases GCH1 levels but also reduces cell proliferation and reactive oxygen species (ROS) levels, mostly because of increased GCH1 accumulation. Furthermore, we identify BH 4/eNOS as downstream of GCH1. Taken together, our results indicate that CT can obviously improve vascular endothelial injury in Type 1 diabetes mellitus (T1DM) rats and reverse the expressions of GCH1 and Smurf2 proteins in aorta of T1DM rats. Smurf2 promotes ubiquitination and degradation of GCH1 through proteasome pathway in HUVECs. We conclude that the Smurf2-GCH1 interaction might represent a potential target for improving endothelial injury.

Barosmin against postprandial hyperglycemia: outputs from computational prediction to functional responses in vitro

Previously, barosmin has been demonstrated to possess anti-diabetic action. However, its effect to inhibit α-amylase and α-glucosidase, including glucose utilization efficacy, has yet to be revealed. Hence, the current study attempted to assess the efficiency of barosmin in inhibiting the α-amylase, α -glucosidase, and dipeptidyl peptidase 4 enzymes, including glucose uptake efficacy. Molecular docking and simulation were performed using AutoDock Vina and Gromacs respectively followed by gene ontology analysis using the database for annotation, visualization, and integrated discovery. Further, in vitro enzyme inhibitory activities and glucose uptake assay were performed in L6 cell lines. Density functional theory analysis detailed mechanistic insights into the crucial interaction sites of barosmin of which the electron-dense region was prone to nucleophilic attack (O-atoms) whereas hydroxyl groups (-OH) showed affinity for electrophilic attacks. Barosmin showed good binding affinity with α-amylase (-9.2 kcal/mol), α-glucosidase (-10.7 kcal/mol), and dipeptidyl peptidase 4 (-10.0 kcal/mol). Barosmin formed stable nonbonded contacts with active site residues of aforementioned enzymes throughout 200 ns molecular dynamics simulation. Further, it regulated pathway concerned with glucose homeostasis i.e. tumor necrosis factor signaling pathway. In addition, barosmin showed α-amylase (IC50= 95.77 ± 23.33 µg/mL), α-glucosidase (IC50= 68.13 ± 2.95 µg/mL), and dipeptidyl peptidase 4 (IC50= 13.27 ± 1.99 µg/mL) inhibitory activities including glucose uptake efficacy in L6 cell lines (EC50= 12.46 ± 0.90 µg/mL) in the presence of insulin. This study presents the efficacy of the barosmin to inhibit α-amylase and α-glucosidase and glucose uptake efficacy in L6 cell lines via the use of multiple system biology tools and in vitro techniques.Communicated by Ramaswamy H. Sarma.

The effects of citrus flavonoids supplementation on endothelial function: A systematic review and dose-response meta-analysis of randomized clinical trials

The present systematic review and dose-response meta-analysis was conducted to synthesize existing data from randomized clinical trials (RCTs) concerning the impact of citrus flavonoids supplementation (CFS) on endothelial function. Relevant RCTs were identified through comprehensive searches of the PubMed, ISI Web of Science, and Scopus databases up to May 30, 2023. Weighted mean differences and their corresponding 95% confidence intervals (CI) were pooled utilizing a random-effects model. A total of eight eligible RCTs, comprising 596 participants, were included in the analysis. The pooled data demonstrated a statistically significant augmentation in flow-mediated vasodilation (FMD) (2.75%; 95% CI: 1.29, 4.20; I2 = 87.3%; p < 0.001) associated with CFS compared to the placebo group. Furthermore, the linear dose-response analysis indicated that each increment of 200 mg/d in CFS led to an increase of 1.09% in FMD (95% CI: 0.70, 1.48; I2 = 94.5%; p < 0.001). The findings from the nonlinear dose-response analysis also revealed a linear relationship between CFS and FMD (Pnon-linearity = 0.903, Pdose-response <0.001). Our findings suggest that CFS enhances endothelial function. However, more extensive RTCs encompassing longer intervention durations and different populations are warranted to establish more precise conclusions.

Baseline and usual triglyceride-glucose index and the risk of chronic kidney disease: a prospective cohort study

Triglyceride-glucose (TyG) index is an emerging marker of adverse cardiometabolic conditions such as cardiovascular disease and type 2 diabetes. The long-term relevance of TyG index to chronic kidney disease (CKD) is uncertain. We aimed to assess the association of TyG index with CKD risk and its utility in risk prediction in a prospective study. The TyG index was calculated using fasting triglycerides and fasting plasma glucose (FPG) levels measured in 2362 men aged 42-61 years with normal kidney function using the formula: Ln (fasting triglycerides [mg/dL] × FPG [mg/dL]/2). Multivariable adjusted hazard ratios (HRs) (95% confidence intervals, CIs) were estimated for CKD. Correction for within-person variability was made using data from repeat measurements of triglycerides and FPG taken 11 years after baseline. Over a median follow-up duration of 17.5 years, 223 CKD cases were recorded. The age-adjusted regression dilution ratio for the TyG index was 0.54 (95% CI, 0.48-0.60). The risk of CKD increased continuously with increasing TyG index across the range 9.3 to 11.6 (p value for nonlinearity<.001). In analysis adjusted for established risk factors, a unit higher TyG index was associated with an increased risk of CKD (HR 1.59, 95% CI 1.24-2.05). Comparing extreme tertiles of the TyG index, the corresponding adjusted HR (95% CI) for CKD was 1.61 (1.15-2.27). Addition of the TyG index to a CKD risk prediction model containing established risk factors improved risk discrimination and reclassification (p value for difference in -2 log likelihood<.001; NRI=47.66%, p=.014; IDI=0.0164, p<.001). Higher TyG index is associated with an increased risk of CKD and improves the prediction and classification of CKD beyond established risk factors. Using single baseline estimations of the TyG index to investigate its association with CKD risk could considerably under-estimate the true association.

Protective effect of alizarin on vascular endothelial dysfunction via inhibiting the type 2 diabetes-induced synthesis of THBS1 and activating the AMPK signaling pathway

BACKGROUND

In this study, we investigated the protective effects of alizarin (AZ) on endothelial dysfunction (ED). AZ has inhibition of the type 2 diabetes mellitus (T2DM)-induced synthesis of thrombospondin 1 (THBS1). Adenosine 5'-monophosphate- activated protein kinase (AMPK), particularly AMPKα2 isoform, plays a critical role in maintaining cardiac homeostasis.

PURPOSE

The aim of this study was to investigate the ameliorative effect of AZ on vascular injury caused by T2DM and to reveal the potential mechanism of AZ in high glucose (HG)-stimulated human umbilical vein endothelial cells (HUVECs) and diabetic model rats.

STUDY DESIGN

HUVECs, rats and AMPK-/- transgenic mice were used to investigate the mitigating effects of AZ on vascular endothelial dysfunction caused by T2DM and its in vitro and in vivo molecular mechanisms.

METHODS

In type 2 diabetes mellitus rats and HUVECs, the inhibitory effect of alizarin on THBS1 synthesis was verified by immunohistochemistry (IHC), immunofluorescence (IF) and Western blot (WB) so that increase endothelial nitric oxide synthase (eNOS) content in vitro and in vivo. In addition, we verified protein interactions with immunoprecipitation (IP). To probe the mechanism, we also performed AMPKα2 transfection. AMPK's pivotal role in AZ-mediated prevention against T2DM-induced vascular endothelial dysfunction was tested using AMPKα2-/- mice.

RESULTS

We first demonstrated that THBS1 and AMPK are targets of AZ. In T2DM, THBS1 was robustly induced by high glucose and inhibited by AZ. Furthermore, AZ activates the AMPK signaling pathway, and recoupled eNOS in stressed endothelial cells which plays a protective role in vascular endothelial dysfunction.

CONCLUSIONS

The main finding of this study is that AZ can play a role in different pathways of vascular injury due to T2DM. Mechanistically, alizarin inhibits the increase in THBS1 protein synthesis after high glucose induction and activates AMPKα2, which increases NO release from eNOS, which is essential in the prevention of vascular endothelial dysfunction caused by T2DM.

Diabetes as risk factor to severity of dengue in naïve patients

Background

Dengue cases can progress to severe ant life-threating forms particularly in subsequent heterologous infections. However, recent studies had explored additional risk factors, including underlying health conditions, even in individuals without prior exposure to dengue, notably, in patients with endothelial dysfunction and chronic inflammation. This study examines the link between diabetes and the development of severe dengue disease in dengue-naive patients during the 2019 dengue outbreak in São Jose do Rio Preto, Brazil.

Methodology

We enrolled 529 laboratory-confirmed dengue cases, identified through DENV RT-PCR or NS1 antigen assays in a hospital cohort of acute febrile illness. Subsequently, we investigated the presence of anti-dengue and anti-Zika IgG antibodies. Samples testing positive for Zika were excluded from the analyses. Two groups were analyzed: naïve (DV-), and dengue history (DV+).

Results

Initially, presence of diabetes and kidney disease, as well as being dengue-naive, were associated with a higher frequency of severe and potentially severe clinical outcomes. Multivariate analysis identified diabetes as a risk factor, while the presence of anti-dengue antibodies was considered protective. Analysis of dengue naïve samples, highlighted diabetes as an independent risk factor to severe forms of dengue disease. In DV+ patients, no condition was highlighted as a risk factor by univariate analysis or multivariate analysis.

Conclusions

We investigated and confirmed diabetes as a risk factor for severe dengue disease in individuals without prior dengue or Zika exposure. Our conclusions raise significant concerns given diabetes' ever increasing global prevalence and its potential impact on patients with or previous dengue exposure.

Aberrant splicing of CaV1.2 calcium channel induced by decreased Rbfox1 enhances arterial constriction during diabetic hyperglycemia

Diabetic hyperglycemia induces dysfunctions of arterial smooth muscle, leading to diabetic vascular complications. The CaV1.2 calcium channel is one primary pathway for Ca2+ influx, which initiates vasoconstriction. However, the long-term regulation mechanism(s) for vascular CaV1.2 functions under hyperglycemic condition remains unknown. Here, Sprague-Dawley rats fed with high-fat diet in combination with low dose streptozotocin and Goto-Kakizaki (GK) rats were used as diabetic models. Isolated mesenteric arteries (MAs) and vascular smooth muscle cells (VSMCs) from rat models were used to assess K+-induced arterial constriction and CaV1.2 channel functions using vascular myograph and whole-cell patch clamp, respectively. K+-induced vasoconstriction is persistently enhanced in the MAs from diabetic rats, and CaV1.2 alternative spliced exon 9* is increased, while exon 33 is decreased in rat diabetic arteries. Furthermore, CaV1.2 channels exhibit hyperpolarized current-voltage and activation curve in VSMCs from diabetic rats, which facilitates the channel function. Unexpectedly, the application of glycated serum (GS), mimicking advanced glycation end-products (AGEs), but not glucose, downregulates the expression of the splicing factor Rbfox1 in VSMCs. Moreover, GS application or Rbfox1 knockdown dynamically regulates alternative exons 9* and 33, leading to facilitated functions of CaV1.2 channels in VSMCs and MAs. Notably, GS increases K+-induced intracellular calcium concentration of VSMCs and the vasoconstriction of MAs. These results reveal that AGEs, not glucose, long-termly regulates CaV1.2 alternative splicing events by decreasing Rbfox1 expression, thereby enhancing channel functions and increasing vasoconstriction under diabetic hyperglycemia. This study identifies the specific molecular mechanism for enhanced vasoconstriction under hyperglycemia, providing a potential target for managing diabetic vascular complications.

NADPH-oxidases as potential pharmacological targets for thrombosis and depression comorbidity

There is a complex interrelationship between the nervous system and the cardiovascular system. Comorbidities of cardiovascular diseases (CVD) with mental disorders, and vice versa, are prevalent. Adults with mental disorders such as anxiety and depression have a higher risk of developing CVD, and people with CVD have an increased risk of being diagnosed with mental disorders. Oxidative stress is one of the many pathways associated with the pathophysiology of brain and cardiovascular disease. Nicotinamide adenine dinucleotide phosphate oxidase (NOX) is one of the major generators of reactive oxygen species (ROS) in mammalian cells, as it is the enzyme that specifically produces superoxide. This review summarizes recent findings on the consequences of NOX activation in thrombosis and depression. It also discusses the therapeutic effects and pharmacological strategies of NOX inhibitors in CVD and brain disorders. A better comprehension of these processes could facilitate the development of new therapeutic approaches for the prevention and treatment of the comorbidity of thrombosis and depression.

DNA-PKcs Phosphorylates Cofilin2 to Induce Endothelial Dysfunction and Microcirculatory Disorder in Endotoxemic Cardiomyopathy

The presence of endotoxemia is strongly linked to the development of endothelial dysfunction and disruption of myocardial microvascular reactivity. These factors play a crucial role in the progression of endotoxemic cardiomyopathy. Sepsis-related multiorgan damage involves the participation of the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs). However, whether DNA-PKcs contributes to endothelial dysfunction and myocardial microvascular dysfunction during endotoxemia remains unclear. Hence, we conducted experiments in mice subjected to lipopolysaccharide (LPS)-induced endotoxemic cardiomyopathy, as well as assays in primary mouse cardiac microvascular endothelial cells. Results showed that endothelial-cell-specific DNA-PKcs ablation markedly attenuated DNA damage, sustained microvessel perfusion, improved endothelial barrier function, inhibited capillary inflammation, restored endothelium-dependent vasodilation, and improved heart function under endotoxemic conditions. Furthermore, we show that upon LPS stress, DNA-PKcs recognizes a TQ motif in cofilin2 and consequently induces its phosphorylation at Thr25. Phosphorylated cofilin2 shows increased affinity for F-actin and promotes F-actin depolymerization, resulting into disruption of the endothelial barrier integrity, microvascular inflammation, and defective eNOS-dependent vasodilation. Accordingly, cofilin2-knockin mice expressing a phospho-defective (T25A) cofilin2 mutant protein showed improved endothelial integrity and myocardial microvascular function upon induction of endotoxemic cardiomyopathy. These findings highlight a novel mechanism whereby DNA-PKcs mediates cofilin2Thr25 phosphorylation and subsequent F-actin depolymerization to contribute to endotoxemia-related cardiac microvascular dysfunction.

Nitric oxide: A potential etiological agent for vaso-occlusive crises in sickle cell disease

Nitric oxide (NO), a vasodilator contributes to the vaso-occlusive crisis associated with the sickle cell disease (SCD). Vascular nitric oxide helps in vasodilation, controlled platelet aggregation, and preventing adhesion of sickled red blood cells to the endothelium. It decreases the expression of pro-inflammatory genes responsible for atherogenesis associated with SCD. Haemolysis and activated endothelium in SCD patients reduce the bioavailability of NO which promotes the severity of sickle cell disease mainly causes vaso-occlusive crises. Additionally, NO depletion can also contribute to the formation of thrombus, which can cause serious complications such as stroke, pulmonary embolism etc. Understanding the multifaceted role of NO provides valuable insights into its therapeutic potential for managing SCD and preventing associated complications. Various clinical trials and studies suggested the importance of artificially induced nitric oxide and its supplements in the reduction of severity. Further research on the mechanisms of NO depletion in SCD is needed to develop more effective treatment strategies and improve the management of this debilitating disease.

N-acetylcysteine and Hydroxychloroquine Ameliorate ADMA-Induced Fetal Growth Restriction in Mice via Regulating Oxidative Stress and Autophagy

Fetal growth restriction (FGR) seriously threatens perinatal health. The main cause of FGR is placental malperfusion, but the specific mechanism is still unclear, and there is no effective treatment for FGR. We constructed a FGR mouse model by adding exogenous asymmetric dimethylarginine (ADMA) through in vivo experiments and found that ADMA could cause placental dysplasia and induce the occurrence of FGR. Compared with the control group, reactive oxygen species (ROS) production in the placenta was increased in mice with FGR, and the expression of autophagy-related proteins p-AKT/AKT, p-mTOR/mTOR, and P62 was significantly decreased, while the expression of Beclin-1 and LC3-II was significantly increased in the FGR group. Furthermore, ADMA had a favorable effect in promoting the formation of autophagosomes. Hydroxychloroquine (HCQ) and N-acetylcysteine (NAC) improved ADMA-induced disorders of placental development and alleviated ADMA-induced FGR. This study found that ADMA could cause excessive autophagy of trophoblasts by increasing the level of oxidative stress, ultimately leading to the occurrence of FGR, and HCQ and NAC had therapeutic effects on ADMA-induced FGR.

Metabolic memory: mechanisms and diseases

Metabolic diseases and their complications impose health and economic burdens worldwide. Evidence from past experimental studies and clinical trials suggests our body may have the ability to remember the past metabolic environment, such as hyperglycemia or hyperlipidemia, thus leading to chronic inflammatory disorders and other diseases even after the elimination of these metabolic environments. The long-term effects of that aberrant metabolism on the body have been summarized as metabolic memory and are found to assume a crucial role in states of health and disease. Multiple molecular mechanisms collectively participate in metabolic memory management, resulting in different cellular alterations as well as tissue and organ dysfunctions, culminating in disease progression and even affecting offspring. The elucidation and expansion of the concept of metabolic memory provides more comprehensive insight into pathogenic mechanisms underlying metabolic diseases and complications and promises to be a new target in disease detection and management. Here, we retrace the history of relevant research on metabolic memory and summarize its salient characteristics. We provide a detailed discussion of the mechanisms by which metabolic memory may be involved in disease development at molecular, cellular, and organ levels, with emphasis on the impact of epigenetic modulations. Finally, we present some of the pivotal findings arguing in favor of targeting metabolic memory to develop therapeutic strategies for metabolic diseases and provide the latest reflections on the consequences of metabolic memory as well as their implications for human health and diseases.

Unveiling the pathogenesis and therapeutic approaches for diabetic nephropathy: insights from panvascular diseases

Diabetic nephropathy (DN) represents a significant microvascular complication in diabetes, entailing intricate molecular pathways and mechanisms associated with cardiorenal vascular diseases. Prolonged hyperglycemia induces renal endothelial dysfunction and damage via metabolic abnormalities, inflammation, and oxidative stress, thereby compromising hemodynamics. Concurrently, fibrotic and sclerotic alterations exacerbate glomerular and tubular injuries. At a macro level, reciprocal communication between the renal microvasculature and systemic circulation establishes a pernicious cycle propelling disease progression. The current management approach emphasizes rigorous control of glycemic levels and blood pressure, with renin-angiotensin system blockade conferring renoprotection. Novel antidiabetic agents exhibit renoprotective effects, potentially mediated through endothelial modulation. Nonetheless, emerging therapies present novel avenues for enhancing patient outcomes and alleviating the disease burden. A precision-based approach, coupled with a comprehensive strategy addressing global vascular risk, will be pivotal in mitigating the cardiorenal burden associated with diabetes.

Diabetes Mellitus to Accelerated Atherosclerosis: Shared Cellular and Molecular Mechanisms in Glucose and Lipid Metabolism

Diabetes is one of the critical independent risk factors for the progression of cardiovascular disease, and the underlying mechanism regarding this association remains poorly understood. Hence, it is urgent to decipher the fundamental pathophysiology and consequently provide new insights into the identification of innovative therapeutic targets for diabetic atherosclerosis. It is now appreciated that different cell types are heavily involved in the progress of diabetic atherosclerosis, including endothelial cells, macrophages, vascular smooth muscle cells, dependence on altered metabolic pathways, intracellular lipids, and high glucose. Additionally, extensive studies have elucidated that diabetes accelerates the odds of atherosclerosis with the explanation that these two chronic disorders share some common mechanisms, such as endothelial dysfunction and inflammation. In this review, we initially summarize the current research and proposed mechanisms and then highlight the role of these three cell types in diabetes-accelerated atherosclerosis and finally establish the mechanism pinpointing the relationship between diabetes and atherosclerosis.

Synergistic effects of Momordica charantia, Nigella sativa, and Anethum graveolens on metabolic syndrome targets: In vitro enzyme inhibition and in silico analyses

Momordica charantia, Nigella sativa, and Anethum graveolens are established medicinal plants possessing noted anti-diabetic and anti-obesity properties. However, the molecular mechanisms underscoring their inhibitory effects on pancreatic lipase, α-glucosidase, and HMG-CoA reductase remain unexplored. This study aimed to elucidate the efficacy of various NS, MC, and AG blends in modulating the enzymatic activity of pancreatic lipase, HMG-CoA reductase, and a-glucosidase, utilizing an integrative approach combining in vitro assessments and molecular modeling techniques. A factorial design matrix generated eight distinct concentration combinations of NS, MC, and AG, subsequently subjected to in vitro enzyme inhibition assays. Molecular docking analyses using AutoDock Vina, molecular dynamics simulations, MMPBSA calculations, and principal component analysis, were executed with Gromacs to discern the interaction dynamics between the compounds and target enzymes. A formulation comprising NS:MC:AG at a 215:50:35 μg/mL ratio yielded significant inhibition of pancreatic lipase (IC50: 74.26 ± 4.27 μg/mL). Moreover, a concentration combination of 215:80:35 μg/mL effectively inhibited both α-glucosidase (IC50: 66.09 ± 3.98 μg/mL) and HMGCR (IC50: 129.03 μg/mL). Notably, MC-derived compounds exhibited superior binding affinity towards all three enzymes, compared to their reference molecules, with diosgenin, Momordicoside I, and diosgenin displaying binding affinities of -11.0, -8.8, and -7.9 kcal/mol with active site residues of pancreatic lipase, α-glucosidase, and HMGCR, respectively. Further, 100 ns molecular dynamics simulations revealed the formation and stabilization of non-bonded interactions between the compounds and the enzymes' active site residues. Through a synergistic application of in vitro and molecular modeling methodologies, this study substantiated the potent inhibitory activity of the NS:MC:AG blend (at a ratio of 215:80:35 μg/mL) and specific MC compounds against pancreatic lipase, α-glucosidase, and HMGCR. These findings provide invaluable insights into the molecular underpinnings of these medicinal plants' anti-diabetic and anti-obesity effects and may guide future therapeutic development.

Salvianolic acids and its potential for cardio-protection against myocardial ischemic reperfusion injury in diabetes

The incidence of diabetes and related mortality rate increase yearly in modern cities. Additionally, elevated glucose levels can result in an increase of reactive oxygen species (ROS), ferroptosis, and the disruption of protective pathways in the heart. These factors collectively heighten the vulnerability of diabetic individuals to myocardial ischemia. Reperfusion therapies have been effectively used in clinical practice. There are limitations to the current clinical methods used to treat myocardial ischemia-reperfusion injury. As a result, reducing post-treatment ischemia/reperfusion injury remains a challenge. Therefore, efforts are underway to provide more efficient therapy. Salvia miltiorrhiza Bunge (Danshen) has been used for centuries in ancient China to treat cardiovascular diseases (CVD) with rare side effects. Salvianolic acid is a water-soluble phenolic compound with potent antioxidant properties and has the greatest hydrophilic property in Danshen. It has recently been discovered that salvianolic acids A (SAA) and B (SAB) are capable of inhibiting apoptosis by targeting the JNK/Akt pathway and the NF-κB pathway, respectively. This review delves into the most recent discoveries regarding the therapeutic and cardioprotective benefits of salvianolic acid for individuals with diabetes. Salvianolic acid shows great potential in myocardial protection in diabetes mellitus. A thorough understanding of the protective mechanism of salvianolic acid could expand its potential uses in developing medicines for treating diabetes mellitus related myocardial ischemia-reperfusion.

Current views on selenoprotein S in the pathophysiological processes of diabetes-induced atherosclerosis: potential therapeutics and underlying biomarkers

Atherosclerotic cardiovascular disease (ASCVD) consistently ranks as the primary mortality factor among diabetic people. A thorough comprehension of the pathophysiological routes and processes activated by atherosclerosis (AS) caused by diabetes mellitus (DM), together with the recognition of new contributing factors, could lead to the discovery of crucial biomarkers and the development of innovative drugs against atherosclerosis. Selenoprotein S (SELENOS) has been implicated in the pathology and progression of numerous conditions, including diabetes, dyslipidemia, obesity, and insulin resistance (IR)-all recognized contributors to endothelial dysfunction (ED), a precursor event to diabetes-induced AS. Hepatic-specific deletion of SELENOS accelerated the onset and progression of obesity, impaired glucose tolerance and insulin sensitivity, and increased hepatic triglycerides (TG) and diacylglycerol (DAG) accumulation; SELENOS expression in subcutaneous and omental adipose tissue was elevated in obese human subjects, and act as a positive regulator for adipogenesis in 3T3-L1 preadipocytes; knockdown of SELENOS in Min6 β-cells induced β-cell apoptosis and reduced cell proliferation. SELENOS also participates in the early stages of AS, notably by enhancing endothelial function, curbing the expression of adhesion molecules, and lessening leukocyte recruitment-actions that collectively reduce the formation of foam cells. Furthermore, SELENOS forestalls the apoptosis of vascular smooth muscle cells (VSMCs) and macrophages, mitigates vascular calcification, and alleviates inflammation in macrophages and CD4+ T cells. These actions help stifle the creation of unstable plaque characterized by thinner fibrous caps, larger necrotic cores, heightened inflammation, and more extensive vascular calcification-features seen in advanced atherosclerotic lesion development. Additionally, serum SELENOS could function as a potential biomarker, and SELENOS single nucleotide polymorphisms (SNPs) rs4965814, rs28628459, and rs9806366, might be effective gene markers for atherosclerosis-related diseases in diabetes. This review accentuates the pathophysiological processes of atherosclerosis in diabetes and amasses current evidence on SELENOS's potential therapeutic benefits or as predictive biomarkers in the various stages of diabetes-induced atherosclerosis.

Protective effect of ellagic acid against high-glucose-induced injury in human umbilical venous endothelial cells

Objective

There is escalating evidence suggesting the beneficial effects of ellagic acid (EA) on the cardiovascular system. The aim of the present study was to investigate the protective effect of EA in human umbilical vein endothelial cells (HUVECs) against high glucose (HG)- induced endothelial dysfunction and to study the potential roles of adropin and nitric oxide (NO) in this regard.

Materials and Methods

The experimental groups consisted of normal and HG (30 mM, 48 hr)-treated HUVECs incubated without or with 5 or 10 μM of EA (6 groups of at least 6 replicates, each). The cell count and viability were studied. Moreover, the markers of the redox state, including malondialdehyde (MDA), the activities of superoxide dismutase (SOD) and catalase enzymes, and ferric reducing anti-oxidant power (FRAP), were assayed. The levels of adropin and eNOS gene expression were also studied using RT-qPCR.

Results

A high concentration of glucose reduced cell count and caused lipid peroxidation, reduced anti-oxidant capacity of the cells, decreased NO levels, and downregulated the expression of NOS3 (encoding eNOS) and ENHO (encoding adropin) genes. Ellagic acid reversed all these effects.

Conclusion

These results suggest a significant protective effect for EA against HG-induced injury in HUVECs. The improved redox state and upregulation of NOS3 and ENHO genes seem to play critical roles in this regard.

Skipping breakfast does not accelerate the hyperglycemia-induced endothelial dysfunction but reduces blood flow of the brachial artery in young men

PURPOSE

Postprandial hyperglycemia is assumed to have a negative impact on flow-mediated dilation (FMD), an index of endothelial function, and blood flow of the peripheral conduit arteries. This study aimed to determine whether the enhancement of postprandial hyperglycemia by skipping breakfast accelerates endothelial dysfunction and reduces the blood flow in the brachial artery in young men.

METHODS

Using a randomized cross-over design, ten healthy men completed two trials: with and without breakfast (Eating and Fasting trials, respectively). Venous blood sampling and brachial FMD tests were conducted before, 30, 60, 90, and 120 min after a 75-g oral glucose tolerance test (OGTT).

RESULTS

Skipping breakfast boosted post-OGTT glucose levels than having breakfast (P = 0.01). The magnitude of the decrease in FMD via OGTT did not vary between trials (main effect of trial P = 0.55). Although brachial blood flow tended to decrease after OGTT in both trials (interaction and main effect of time P = 0.61 and P = 0.054, respectively), the decrease in blood flow following OGTT was greater in the Fasting trial than in the Eating trial (main effect of trial, mean difference =  - 15.8 mL/min [95%CI =  - 25.6 to - 6.0 mL/min], P < 0.01).

CONCLUSION

Skipping breakfast did not enhance the magnitude of the decrease in FMD following glucose loading, but did accelerate hyperglycemia-induced reduction in brachial blood flow. Current findings suggest that even missing one breakfast has negative impacts on the blood flow regulation of the peripheral conduit arteries in young men who habitually eat breakfast.