Macro- and microvascular endothelial dysfunction in diabetes

Association between life's essential 8 and diabetic kidney disease: a population-based study

BACKGROUND AND AIMS

Diabetic patients are highly susceptible to cardiovascular and renal diseases. As a newly updated comprehensive index for assessing cardiovascular health (CVH), Life's essential 8 (LE8) has the potential to serve as a practical tool for evaluating the risk of diabetic kidney disease (DKD). We are committed to exploring the relationship between LE8 and its subscales with DKD in diabetic patients, aiming to provide preliminary evidence for the formulation of clinical strategies.

METHODS AND RESULTS

A total of 3,715 NHANES participants were included in this study, representing 18.9 million non-institutionalized residents of the United States. The mean age of all subjects was 59.72 years, and the weighted prevalence of DKD among diabetic patients was 36.39%. After adjusting for potential confounding factors, it was found that compared to the low LE8 group, the risk of developing DKD was significantly lower in the moderate LE8 group (OR: 0.54, 95% CI: 0.43-0.66) and the high LE8 group (OR: 0.18, 95% CI: 0.08-0.42). A similar trend was observed across the subscales of the LE8 score. The results of the fully adjusted restricted cubic spline regression analysis revealed a linear relationship between LE8 and its subscales with DKD. The findings remained consistent in subgroup and sensitivity analyses, with no significant interactions observed between subgroups.

CONCLUSION

Higher scores on the LE8 and its subscales were associated with a lower risk of developing DKD. However, the long-term causal relationship between LE8 and DKD risk necessitates further validation and exploration through large-scale, rigorously designed prospective studies.

Raster Scan Optoacoustic Mesoscopy for detecting microvascular complications in diabetes mellitus: A narrative brief review

Diabetes mellitus (DM) may lead to microvascular and macrovascular complications. Screening for these complications is crucial, and so non-invasive methods with high-dissemination potential are needed. Diabetic peripheral neuropathy (DPN) is particularly challenging to screen due to the lack of reliable clinical markers and endpoints. In this context, Raster Scan Optoacoustic Mesoscopy (RSOM) emerges as a highly promising technique that offers hybrid, non-invasive imaging of optical absorption using light-induced ultrasound waves within tissue without the use of contrast agents. RSOM provides high-resolution visualisation of micro-vasculature and other tissue structures along with functional information. The technique has already assessed microvasculature loss as a function of diabetes progression and used it to characterise DPN severity. RSOM has also shown that cutaneous vessels in the mesoscopic range (mean diameters of 30-40 µm) are most prominently affected by DM and that the mean number of cutaneous vessels was lower in subjects with DM than in healthy participants (p < 0.001 and p < 0.05, respectively). Although experience is still limited, we present an overview of the novel technique in relation to its potential for detecting early DM onset and development of microvascular complications.

Enhanced STIM1 expression drives platelet hyperactivity in diabetes

Stromal interaction molecule 1 (STIM1), a key regulator of calcium signaling located in the endoplasmic reticulum, is crucial for platelet function. While elevated STIM1 expression is observed in platelets from diabetic patients, its role in diabetes-induced platelet hyperreactivity remains unclear. In this study, we found a positive correlation between STIM1 expression and agonist-induced platelet aggregation in platelets from patients with type 2 diabetes mellitus (T2DM). Platelets with high STIM1 expression exhibited enhanced aggregation, P-selectin release, integrin αIIbβ3 activation, spreading, and clot retraction compared to those with low STIM1 expression. Similar findings were observed in db/db mice. Furthermore, the store-operated calcium entry channel inhibitor CM4620 demonstrated superior antiplatelet and antithrombotic efficacy compared to aspirin in both db/db mice and patients with T2DM. Our results suggest that elevated STIM1 expression contributes to enhanced platelet reactivity in diabetes, and targeting STIM1 may offer a promising novel therapeutic approach for thrombosis prevention in this patient population.

KLF5 enhances CXCL12 transcription in adipose-derived stem cells to promote endothelial progenitor cells neovascularization and accelerate diabetic wound healing

BACKGROUND

Adipose-derived stem cells (ADSCs) have been shown to accelerate diabetic wound healing by promoting neovascularization, though the underlying mechanisms are not fully understood. This study aims to explore whether ADSCs influence endothelial progenitor cells (EPCs) function to enhance diabetic wound healing.

METHODS

Human adipose-derived stem cells (hADSCs) were isolated from patient adipose tissue and cultured under normal and high glucose (HG) conditions. RNA sequencing analyzed gene expression, while immunofluorescence validated findings in patient wound tissues. Mouse adipose-derived stem cells (ADSCs) from C57BL/6 mice were evaluated in vitro for their effects on EPCs under HG using EdU, Transwell, and tube formation assays. A diabetic mouse wound model was used to assess ADSCs therapeutic effects via digital imaging, histology, and immunofluorescence. Kruppel-like factor 5 (KLF5), identified via the JASPAR database, was confirmed by immunohistochemistry and immunofluorescence. KLF5 and C-X-C motif chemokine 12 (CXCL12) expression levels were measured by enzyme-linked immunosorbent assay (ELISA), western blot, and quantitative reverse transcription polymerase chain reaction (RT-qPCR), and their relationship was validated through dual-luciferase assays.

RESULTS

We constructed a neovascularization-related signature (NRS) comprising 75 genes on the basis of differentially expressed genes (DEGs) linked to neovascularization. GO and KEGG analyses revealed that the NRS is primarily involved in vasculature development and receptor-ligand activity. Seven hub genes (CD34, CXCL12, FGF7, FGF18, FGF1, TEK, KIT) were identified and validated. In a diabetic mouse model, CXCL12 knockdown in ADSCs reduced their ability of promoting wound healing and neovascularization. KLF5 expression was lower in patients with diabetic ulcers and diabetic mice wound tissues compared with normal tissues, while ADSCs treatment significantly increased KLF5 expression in diabetic mice wounds. Dual-luciferase reporter assays confirmed KLF5 as an upstream transcription factor of CXCL12. Additionally, knocking down KLF5 in ADSCs impaired their therapeutic effects on diabetic wound healing. In vitro, the addition of exogenous CXCL12 recombinant protein restored EPCs proliferation, migration, and vasculogenic capacity in a high glucose environment after KLF5 silencing in ADSCs.

CONCLUSIONS

Our findings underscore the pivotal role of KLF5 in enhancing CXCL12 transcription within ADSCs, thereby facilitating EPC-mediated neovascularization and improving diabetic wound healing. Additionally, KLF5 emerges as a promising therapeutic target for accelerating tissue repair in diabetic wounds.

Formononetin: a review of its source, pharmacology, drug combination, toxicity, derivatives, and drug delivery systems

Formononetin (FMN) is a common natural metabolite that can be extracted and isolated from some common botanical drugs. In recent years, FMN has garnered increasing attention due to its beneficial biological activities. In this paper, we systematically summarize the sources of FMN and provide a comprehensive review of its pharmacological activities and molecular mechanisms, co-administration, toxicity, derivatives, and drug delivery systems in the last 5 years. The study results found that FMN has a wide range of pharmacological activities in neurological disorders, organ damage and cancer, showing great potential for clinical application and broad prospects. Researchers are exploring various types of delivery systems, including nanoparticle carriers, ligand modifications and polymer microspheres. These advanced delivery systems can enhance the stability of FMN, prolong its release time in vivo, and improve targeting, thereby optimizing its therapeutic efficacy and reducing side effects, and greatly improving its bioavailability. In conclusion, FMN is a natural metabolite with considerable research value, and its diverse biological activities make it a promising candidate for drug development and medical research.

High Glucose Treatment Induces Nuclei Aggregation of Microvascular Endothelial Cells via the foxo1a-klf2a Pathway

BACKGROUND

Hyperglycemia is a major contributor to endothelial dysfunction and blood vessel damage, leading to severe diabetic microvascular complications. Despite the growing body of research on the underlying mechanisms of endothelial cell (EC) dysfunction, the available drugs based on current knowledge fall short of effectively alleviating these complications. Therefore, our endeavor to explore novel insights into the cellular and molecular mechanisms of endothelial dysfunction is crucial for the field.

METHODS

In this study, we performed a high-resolution imaging and time-lapse imaging analysis of the behavior of ECs in Tg(kdrl:ras-mCherry::fli1a:nGFP) zebrafish embryos upon high glucose treatment. Genetic manipulation and chemical biology approaches were utilized to analyze the underlying mechanism of high glucose-induced nuclei aggregation and aberrant migration of zebrafish ECs and cultured human ECs. Bioinformatical analysis of single-cell RNA-sequencing data and molecular biological techniques was performed to identify the target genes of foxo1a.

RESULTS

In this study, we observed that the high glucose treatment resulted in nuclei aggregation of ECs in zebrafish intersegmental vessels. Additionally, the aberrant migration of microvascular ECs in high glucose-treated embryos, which might be a cause of nuclei aggregation, was discovered. High glucose induced aggregation of vascular endothelial nuclei via foxo1a downregulation in zebrafish embryos. Then, we revealed that high glucose resulted in the downregulation of foxo1a expression and increased the expression of its direct downstream effector, klf2a, through which the aberrant migration and aggregation of vascular endothelial nuclei were caused.

CONCLUSIONS

High glucose treatment caused the nuclei of ECs to aggregate in vivo, which resembles the crowded nuclei of ECs in microaneurysms. High glucose suppresses foxo1a expression and increases the expression of its downstream effector, klf2a, thereby causing the aberrant migration and aggregation of vascular endothelial nuclei. Our findings provide a novel insight into the mechanism of microvascular complications in hyperglycemia.

SGLT2 inhibition improves endothelium-independent vasodilatory function in type 2 diabetes: A double-blind, randomized, placebo-controlled crossover trial

AIMS

The objective of this study was to examine the effects of empagliflozin on endothelium-dependent and endothelium-independent vasodilatation and systemic hemodynamic parameters and to assess the role of the nitric oxide (NO) system in patients with type 2 diabetes (T2DM).

MATERIALS AND METHODS

In this double-blind, placebo-controlled cross over trial, patients with T2DM were treated with either empagliflozin 10 mg or matching placebo for 4 weeks. Following a 2-week washout, participants were crossed over to 4 weeks of the opposite treatment. Forearm blood flow (FBF) was measured after each treatment period using venous occlusion plethysmography. Acetylcholine and sodium nitroprusside (SNP) were infused into the brachial artery to assess endothelium-dependent and endothelium-independent vasodilatory function, respectively. Total peripheral resistance, 24-h blood pressure (BP) and biochemical markers of NO activity were measured as well.

RESULTS

Sixteen participants completed the trial. The mean age was 68 ± 8 years, and 69% were male. The SNP response increased by 21% (geometric mean ratio 1.21, 95% CI: 1.09; 1.33) during treatment with empagliflozin compared to placebo (p ≤ 0.001), but not during acetylcholine infusion (p = 0.290). Empagliflozin decreased 24-h systolic BP by 5 mmHg (95% CI: -9; -1 mmHg) (p = 0.015), diastolic BP by 2 mmHg (95% CI: -5; 0 mmHg) (p = 0.029) and systemic vascular resistance by 48 dyn×s/m5 (95% CI: -94; -1 dyn×s/m5) (p = 0.044). Furthermore, empagliflozin reduced plasma levels of nitrite and urinary levels of NOx.

CONCLUSIONS

Empagliflozin improves endothelium-independent vasodilation, reduces vascular resistance and lowers 24-h BP in patients with T2DM, whereas no change in endothelial-dependent vasodilation was observed.

TRIAL REGISTRATION

EU Clinical Trials Register number: 2019-004303-12 (https://www.clinicaltrialsregister.eu/ctr-search/trial/2019-004303-12/DK).

Evaluation of the Effect of Acute Elevated Intraocular Pressure on Retinal and Choroidal Microvasculature in Diabetic Rats

Purpose

Understanding the dynamics of blood flow regulation in diabetic conditions is crucial for developing targeted interventions. This study aimed to investigate the impact of acute intraocular pressure (IOP) elevation on retinal and choroidal microvasculature in diabetic and control rats.

Methods

Male Sprague-Dawley rats were divided into two groups: diabetic and control. Acute IOP elevation was achieved through controlled perfusion pressure. Retinal and choroidal blood flow was measured using Swept-Source Optical Coherence Tomography Angiography (SS-OCT/OCTA).

Results

At baseline IOP levels, there were no statistically significant differences in perfusion area (PA) between the two groups in all regions of the retina and choroid. During acute IOP elevation, both diabetic and control rats experienced a significant reduction in retinal and choroidal blood flow perfusion. Diabetic rats manifested significantly higher (P<0.05) alterations in PA across nearly all retinal regions compared to the control group, barring specific sub-regions of the outer ring. Concerning choroidal PA, the diabetic group exhibited a more pronounced alteration than the control group across the entire 6-mm region and certain sub-regions of the outer ring.

Conclusion

Our results demonstrate a clear association between diabetes and impaired choroidal vascular autoregulation during acute IOP elevation. The observed reduction in retinal and choroidal microvasculature in diabetic rats points towards a compromised ability to maintain blood flow homeostasis under stress conditions.

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.

Association between all-cause mortality and vascular complications in U.S. adults with newly diagnosed type 2 diabetes (NHANES 1999-2018)

AIMS

The impact of macrovascular and microvascular complications, the common vascular complications of type 2 diabetes, on long-term mortality has been well evaluated, but the impact of different complications of newly diagnosed type 2 diabetes (diagnosed within the past 2 years) on long-term mortality has not been reported. We aimed to investigate the relationship between all-cause mortality and vascular complications in U.S. adults (aged ≥ 20 years) with newly diagnosed type 2 diabetes.

METHODS

We used data from the 1999-2018 National Health and Nutritional Examination Surveys (NHANES). Cox proportional hazard models was used to assess hazard ratios (HR) and 95% confidence intervals for all-cause mortality.

RESULTS

A total of 928 participants were enrolled in this study. At a mean follow-up of 10.8 years, 181 individuals died. In the fully adjusted model, the hazard ratio (HR) (95% confidence interval [CI]) of all-cause mortality for individuals with any single complication compared with those with newly diagnosed type 2 diabetes without complications was 2.24 (1.37, 3.69), and for individuals with two or more complications was 5.34 (3.01, 9.46).Co-existing Chronic kidney disease (CKD) and diabetic retinopathy (DR) at baseline were associated with the highest risk of death (HR 6.07[2.92-12.62]), followed by CKD and cardiovascular disease (CVD) (HR 4.98[2.79-8.89]) and CVD and DR (HR 4.58 [1.98-10.57]).

CONCLUSION

The presence of single and combined diabetes complications exerts a long-term synergistic adverse impact on overall mortality in newly diagnosed U.S. adults with type 2 diabetes, underscoring the importance of comprehensive complication screening to enhance risk stratification and treatment.

Association between hyperglycemia during pregnancy and offspring's refractive error: A focused review

This review article explores the relationship between hyperglycemia during pregnancy and the visual development of offspring, specifically focusing on refractive error. The authors conducted a comprehensive search for relevant articles in various databases and assessed the methodological quality of the included studies. The findings consistently indicate that hyperglycemia during pregnancy can have a detrimental impact on the structural and functional aspects of visual development in offspring. The intrauterine hyperglycemic environment appears to negatively affect the retina and lens, leading to refractive errors. In conclusion, there is likely an association between hyperglycemia during pregnancy and the development of refractive errors in offspring.

Association of Novel Clinical and Behavioural Markers with HbA1c Improvement: A Latent Class Analysis of 912 Patients with Type 2 Diabetes Mellitus

OBJECTIVE

The escalating prevalence of Type 2 Diabetes Mellitus (T2DM) overwhelms healthcare systems. Lifestyle interventions enhancing patient monitoring and adherence vary in efficacy, emphasizing the need to understand differential response across patient subgroups. This study aimed to segment patients with T2DM into distinct latent classes and identify characteristics associated with optimal 12-month glycated haemoglobin (HbA1c) reduction.

METHODS

We prospectively recruited 1000 patients with T2DM from government-funded outpatient clinics in Singapore, aged ≥ 40-year-old with HbA1c ≥ 7.0 %. Exclusion criteria included insulin treatment and cognitive impairment. Latent class analysis was applied to 912 patients, using mHealth interventions, age, education, living arrangement, baseline HbA1c, step count, and motivation (Patient Activation Measure) as indicators. 12-Month HbA1c reduction was assessed with one-way ANOVA and pairwise T-test.

RESULTS

Within cohort, younger patients with higher education, physical activity, and baseline HbA1c exhibited the greatest HbA1c improvement (1.14 ± 1.79 %). Younger patients with lower education, despite high baseline HbA1c, exhibited a moderately lower HbA1c improvement (0.52 ± 1.41 %).

CONCLUSION

Individuals with higher baseline HbA1c, education, motivation, and activity levels experienced the most significant HbA1c reductions in response to lifestyle interventions. A tailored approach to these modifiable characteristics may help patients achieve substantial 12-month HbA1c reductions.

HucMSCs can alleviate abnormal vasculogenesis induced by high glucose through the MAPK signaling pathway

Vascular complications caused by diabetes mellitus contribute a major threat to increased disability and mortality of diabetic patients, which are characterized by damaged endothelial cells and angiogenesis. Human umbilical cord-derived mesenchymal stem cells (hucMSCs) have been demonstrated to alleviate endothelial cell damage and improve angiogenesis. However, these investigations overlooked the pivotal role of vasculogenesis. In this study, we utilized blood vessel organoids (BVOs) to investigate the impact of high glucose on vasculogenesis and subsequent angiogenesis. We found that BVOs in the vascular lineage induction stage were more sensitive to high glucose and more susceptible to affect endothelial cell differentiation and function. Moreover, hucMSCs can alleviate the high glucose-induced inhibition of endothelial cell differentiation and dysfunction through MAPK signaling pathway downregulation, with the MAPK activator dimethyl fumarate further illustrating the results. Thereby, we demonstrated that high glucose can lead to abnormal vasculogenesis and impact subsequent angiogenesis, and hucMSCs can alleviate this effect.

β-Arrestin-2 enhances endoplasmic reticulum stress-induced glomerular endothelial cell injury by activating transcription factor 6 in diabetic nephropathy

BACKGROUND

Glomerular endothelial cell (GENC) injury is a characteristic of early-stage diabetic nephropathy (DN), and the investigation of potential therapeutic targets for preventing GENC injury is of clinical importance.

AIM

To investigate the role of β-arrestin-2 in GENCs under DN conditions.

METHODS

Eight-week-old C57BL/6J mice were intraperitoneally injected with streptozotocin to induce DN. GENCs were transfected with plasmids containing siRNA-β-arrestin-2, shRNA-activating transcription factor 6 (ATF6), pCDNA-β-arrestin-2, or pCDNA-ATF6. Additionally, adeno-associated virus (AAV) containing shRNA-β-arrestin-2 was administered via a tail vein injection in DN mice.

RESULTS

The upregulation of β-arrestin-2 was observed in patients with DN as well as in GENCs from DN mice. Knockdown of β-arrestin-2 reduced apoptosis in high glucose-treated GENCs, which was reversed by the overexpression of ATF6. Moreover, overexpression of β-arrestin-2 Led to the activation of endoplasmic reticulum (ER) stress and the apoptosis of GENCs which could be mitigated by silencing of ATF6. Furthermore, knockdown of β-arrestin-2 by the administration of AAV-shRNA-β-arrestin-2 alleviated renal injury in DN mice.

CONCLUSION

Knockdown of β-arrestin-2 prevents GENC apoptosis by inhibiting ATF6-mediated ER stress in vivo and in vitro. Consequently, β-arrestin-2 may represent a promising therapeutic target for the clinical management of patients with DN.

TRPV1: A novel target for the therapy of diabetes and diabetic complications

BACKGROUND

Diabetes mellitus is a chronic metabolic disease characterized by abnormally elevated blood glucose levels. Type II diabetes accounts for approximately 90% of all cases. Several drugs are available for hyperglycemia treatment. However, the current therapies for managing high blood glucose do not prevent or reverse the disease progression, which may result in complications and adverse effects, including diabetic neuropathy, retinopathy, and nephropathy. Hence, developing safer and more effective methods for lowering blood glucose levels is imperative. Transient receptor potential vanilloid-1 (TRPV1) is a significant member of the transient receptor potential family. It is present in numerous body tissues and organs and performs vital physiological functions.

PURPOSE

This review aimed to develop new targeted TRPV1 hypoglycemic drugs by systematically summarizing the mechanism of action of the TRPV1-based signaling pathway in preventing and treating diabetes and its complications.

METHODS

Literature searches were performed in the PubMed, Web of Science, Google Scholar, Medline, and Scopus databases for 10 years from 2013 to 2023. The search terms included "diabetes," "TRPV1," "diabetic complications," and "capsaicin."

RESULTS

TRPV1 is an essential potential target for treating diabetes mellitus and its complications. It reduces hepatic glucose production and food intake and promotes thermogenesis, metabolism, and insulin secretion. Activation of TRPV1 ameliorates diabetic nephropathy, retinopathy, myocardial infarction, vascular endothelial dysfunction, gastroparesis, and bladder dysfunction. Suppression of TRPV1 improves diabetes-related osteoporosis. However, the therapeutic effects of activating or suppressing TRPV1 may vary when treating diabetic neuropathy and periodontitis.

CONCLUSION

This review demonstrates that TRPV1 is a potential therapeutic target for diabetes and its complications. Additionally, it provides a theoretical basis for developing new hypoglycemic drugs that target TRPV1.

The impact of donor diabetes on recipient postoperative complications, renal function, and survival rate in deceased donor kidney transplantation: a single-center analysis

As the global incidence of diabetes rises and diagnoses among younger patients increase, transplant centers worldwide are encountering more organ donors with diabetes. This study examined 80 donors and 160 recipients, including 30 donors with diabetes (DD) and their 60 recipients (DDR). The control group comprised 50 non-diabetic donors (ND) and 100 recipients (NDR). We analyzed clinical, biochemical, and pathological data for both diabetic and control groups, using logistic regression to identify risk factors for delayed graft function (DGF) after kidney transplantation. Results showed that pre-procurement blood urea nitrogen levels were significantly higher in DD [18.20 ± 10.63 vs. 10.86 ± 6.92, p = 0.002] compared to ND. Renal pathological damage in DD was notably more severe, likely contributing to the higher DGF incidence in DDR compared to NDR. Although DDR had poorer renal function during the first three months post-transplant, both groups showed similar renal function thereafter. No significant differences were observed in 1-year or 3-year mortality rates or graft failure rates between DDR and NDR. Notably, according to the Renal Pathology Society (RPS) grading system, kidneys from diabetic donors with a grade > IIb are associated with significantly lower postoperative survival rates. Recipient gender [OR: 5.452 (1.330-22.353), p = 0.013] and pre-transplant PRA positivity [OR: 34.879 (7.698-158.030), p < 0.001] were identified as independent predictors of DGF in DDR. In conclusion, transplant centers may consider utilizing kidneys from diabetic donors, provided they are evaluated pathologically, without adversely impacting recipient survival and graft failure rates.

Single-Cell Meta-Analysis Uncovers the Pancreatic Endothelial Cell Transcriptomic Signature and Reveals a Key Role for NKX2-3 in PLVAP Expression

BACKGROUND

The pancreatic vasculature displays tissue-specific physiological and functional adaptations that support rapid insulin response by β-cells. However, the digestive enzymes have made it difficult to characterize pancreatic endothelial cells (ECs), resulting in the poor understanding of pancreatic EC specialization.

METHODS

Available single-nuclei/single-cell RNA-sequencing data sets were mined to identify pancreatic EC-enriched signature genes and to develop an integrated atlas of human pancreatic ECs. We validated the findings using independent single-nuclei/single-cell RNA-sequencing data, bulk RNA-sequencing data of isolated ECs, spatial transcriptomics data, immunofluorescence, and RNAScope of selected markers. The NK2 homeobox 3 (NKX2-3) TF (transcription factor) was expressed in HUVECs via gene transfection, and the expression of pancreatic EC-enriched signature genes was assessed via RT-qPCR.

RESULTS

We defined a pancreatic EC-enriched gene signature conserved across species and developmental stages that included genes involved in ECM (extracellular matrix) composition (COL15A1 and COL4A1), permeability and barrier function (PLVAP, EHD4, CAVIN3, HSPG2, ROBO4, HEG1, and CLEC14A), and key signaling pathways (S1P [sphingosine-1-phosphate], TGF-β [transforming growth factor-β], RHO/RAC GTPase [guanosine triphosphatase], PI3K/AKT [phosphoinositide 3-kinase/protein kinase B], and PDGF [platelet-derived growth factor]). The integrated atlas revealed the vascular hierarchy within the pancreas. We identified and validated a specialized islet capillary subpopulation characterized by genes involved in permeability (PLVAP and EHD4), immune-modulation (FABP5, HLA-C, and B2M), ECM composition (SPARC and SPARCL1), IGF (insulin-like growth factor) signaling (IGFBP7), and membrane transport (SLCO2A1, SLC2A3, and CD320). Importantly, we identified NKX2-3 as a key TF enriched in pancreatic ECs. DNA-binding motif analysis found NKX2-3 motifs in ≈40% of the signature genes. Induction of NKX2-3 in HUVECs promoted the expression of the islet capillary EC-enriched genes PLVAP and SPARCL1.

CONCLUSIONS

We defined a validated transcriptomic signature of pancreatic ECs and uncovered their intratissue transcriptomic heterogeneity. We showed that NKX2-3 acts upstream of PLVAP and provided a single-cell online resource that can be further explored by the community: https://vasconcelos.shinyapps.io/pancreatic_endothelial/.

The Potential of Mesenchymal Stem/Stromal Cells in Diabetic Wounds and Future Directions for Research and Therapy-Is It Time for Use in Everyday Practice?

The treatment of diabetic wounds is impaired by the intricate nature of diabetes and its associated complications, necessitating novel strategies. The utilization of mesenchymal stem/stromal cells (MSCs) as a therapeutic modality for chronic and recalcitrant wounds in diabetic patients is an active area of investigation aimed at enhancing its therapeutic potential covering tissue regeneration. The threat posed to the patient and their environment by the presence of a diabetic foot ulcer (DFU) is so significant that any additional therapeutic approach that opens new pathways to halt the progression of local changes, which subsequently lead to a generalized inflammatory process, offers a chance to reduce the risk of amputation or even death. This article explores the potential of MSCs in diabetic foot ulcer treatment, examining their mechanisms of action, clinical application challenges, and future directions for research and therapy.

Targeting endothelial KCa channels in vivo restores arterial and endothelial function in type 2 diabetic rats

OBJECTIVE

This study tested the hypothesis that administration of the KCa channel activator SKA-31 restores endothelium-dependent vasodilation in vivo in Type 2 Diabetic (T2D) rats.

BACKGROUND

Acute treatment of isolated resistance arteries from T2D rats and humans with SKA-31 significantly improved endothelium-dependent vasodilation. However, it is unknown whether these in situ actions translate to intact vascular beds in vivo.

METHODS

Male Sprague Dawley (SD) and T2D Goto-Kakizaki (GK) rats (26-32 weeks of age) were injected intraperitoneally with either drug vehicle or 10 mg/kg SKA-31. Doppler ultrasound imaging was used to record reactive hyperemia/flow-mediated dilation (FMD) in the femoral artery following release of an occlusion cuff on the distal hind limb, along with diameter changes in the left main coronary artery in response to inhaled isoflurane (2 % → 5 %).

RESULTS

Vehicle treated SD rats exhibited a robust and reversible FMD response, the magnitude and time course of which did not differ in SD rats treated with SKA-31. In contrast, only a weak FMD response was observed in vehicle-treated T2D GK rats, whereas prior SKA-31 administration restored FMD to the level observed in control SD rats. Exposure of SD rats to 5 % isoflurane caused robust coronary artery dilation, which was not altered by prior treatment with SKA-31. In T2D GK rats, 5 % isoflurane inhalation alone did not increase coronary artery diameter, however, a strong vasodilatory response was observed following SKA-31 treatment. SKA-31 administration did not modify intrinsic heart rate responses in either protocol.

CONCLUSIONS

Enhancement of KCa channel activity in vivo restores endothelium-dependent vasodilation in T2D rats that exhibit peripheral endothelial dysfunction.

Effect of esaxerenone on the onset of aortic endothelial dysfunction and circulating microparticles in type 1 diabetic male mice

Endothelial dysfunction exacerbates hypertension and other vascular complications in diabetes mellitus (DM). Circulating microparticles (MPs) and extracellular vesicles released in patients with DM have emerged as novel regulators of endothelial dysfunction. The obstruction of mineralocorticoid receptors (MRs) is a potential therapeutic approach to reduce cardiovascular complications. Their impact on the obstruction of MRs on circulating MPs and endothelial dysfunction in DM remains unclear. DM was induced in mice through a single intravenous dose of streptozotocin (STZ; 200 mg/kg). Esaxerenone (ESAX; 3 mg/kg/day), a MR blocker was administered via diet for 8 weeks. In this study, the aortas of the DM group showed the endothelial dysfunction and the administration of ESAX ameliorated the endothelial-dependent responses. Moreover, ESAX influences the impaired endothelial-dependent responses of DM-derived MPs. Interestingly, MP levels increased in DM whereas decreased after ESAX administration. In the aorta, the DM-derived MPs increased the expression of intercellular adhesion molecule-1 (ICAM-1). ESAX inhibited the adhesion of DM-derived MPs. Moreover, the ICAM-1 inhibitor A205804 shows similar effects as ESAX. These results indicate that the release and adhesion properties of MPs can be partially obstructed by ESAX via the ICAM-1 signaling pathway, which clarifies the other functions beyond the anti-hypertensive effects of ESAX.

Therapeutic potential of relaxin or relaxin mimetics in managing cardiovascular complications of diabetes

Diabetes mellitus is a metabolic disease with an escalating global prevalence. Despite the abundance and relative efficacies of current therapeutic approaches, they primarily focus on attaining the intended glycaemic targets, but patients ultimately still suffer from various diabetes-associated complications such as retinopathy, nephropathy, cardiomyopathy, and atherosclerosis. There is a need to explore innovative and effective diabetic treatment strategies that not only address the condition itself but also combat its complications. One promising option is the reproductive hormone relaxin, an endogenous ligand of the RXFP1 receptor. Relaxin is known to exert beneficial actions on the cardiovascular system through its vasoprotective, anti-inflammatory and anti-fibrotic effects. Nevertheless, the native relaxin peptide exhibits a short biological half-life, limiting its therapeutic potential. Recently, several relaxin mimetics and innovative delivery technologies have been developed to extend its biological half-life and efficacy. The current review provides a comprehensive landscape of the cardiovascular effects of relaxin, focusing on its potential therapeutic applications in managing complications associated with diabetes. The latest advancements in the development of relaxin mimetics and delivery methods for the treatment of cardiometabolic disorders are also discussed.

Role of the Pancreatic Islet Microvasculature in Health and Disease

The pancreatic islet vasculature comprises microvascular endothelial cells surrounded by mural cells (pericytes). Both cell types support the islet by providing (1) a conduit for delivery and exchange of nutrients and hormones; (2) paracrine signals and extracellular matrix (ECM) components that support islet development, architecture, and endocrine function; and (3) a barrier against inflammation and immune cell infiltration. In type 2 diabetes, the islet vasculature becomes inflamed, showing loss of endothelial cells, detachment, and/or trans-differentiation of pericytes, vessel dilation, and excessive ECM deposition. While most work to date has focused either on endothelial cells or pericytes in isolation, it is very likely that the interaction between these cell types and disruption of that interaction in diabetes are critically important. In fact, dissociation of pericytes from endothelial cells is an early, key feature of microvascular disease in multiple tissues/disease states. Moreover, in beta-cell replacement therapy, co-transplantation with microvessels versus endothelial cells alone is substantially more effective in improving survival and function of the transplanted cells. Ongoing studies, including characterization of islet vascular cell signatures, will aid in the identification of new therapeutic targets aimed at improving islet function and benefiting people living with all forms of diabetes.

Plasma glucose, HbA1c, insulin and lipid profile in Sudanese type 2 diabetic patients with cardiovascular disease: a case control study

Background: Type 2 diabetes mellitus (T2DM) and its consequences are a serious global public health issue. By 2030, the number of people with type 2 diabetes is predicted to reach 439 million. The purpose of this study is to evaluate the plasma levels of glucose, HbA1c, insulin, and lipid profile in Sudanese T2DM patients. Methods: This case control study included 165 Sudanese patients with diabetic type 2 and a cardiovascular condition as cases and 165 diabetic type 2 volunteers without a cardiovascular disorder as controls. The concentrations of plasma glucose, HbA1c, and lipid profile were assessed using a Mindray BS-480 auto-chemistry analyzer, and insulin was analyzed using a Cobase 411 auto analyzer. The collected data were analyzed using statistical tools for social science computer programs (SPSS version 21). Results: According to the findings, (59.4%) of patients between the ages of (50-69). Females made up 50.9%. (38.2%) of patients had an illness duration of between (8-15 years). (41.8%) of individuals did not have hypertension. There was a substantial rise in BMI, FBG, HbA1c, HDL-C, and insulin among diabetics with cardiovascular disease compared to diabetics without cardiovascular disease (p-value = 0.001, 0.000, 0.018, and 0.000). Females had significantly higher blood TC, LDL-C, HDL-C, and BMI than males (p-values = 0.000, 0,001, and 0.000, respectively). There were significant positive correlation between FBS, HBA1c, insulin and duration of disease (r=0.155, p, value=0.005) (r=0.160, p, value=0.004)(r=0.103, p. value=0.061)respectively, while there were significant negative correlation between TC, TG,LDL-C, HDL-C and duration of disease (r=-0.152, p, value= 0.006)(r=-0.023, p, value=0.678)(r=-0.113, p, value= 0.040)(r=-0.145, p, value=0.008)respectively. Conclusion: When comparing diabetics with cardiovascular disease to diabetics without cardiovascular disease, there was a substantial rise in BMI, FBG, HbA1c, HDL-C, and insulin. FBS, HBA1c, insulin, and illness duration all had a strong positive connection.

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.

Impact of different hormones on the regulation of nitric oxide in diabetes

Polymetabolic syndrome achieved pandemic proportions and dramatically influenced public health systems functioning worldwide. Chronic vascular complications are the major contributors to increased morbidity, disability, and mortality rates in diabetes patients. Nitric oxide (NO) is among the most important vascular bed function regulators. However, NO homeostasis is significantly deranged in pathological conditions. Additionally, different hormones directly or indirectly affect NO production and activity and subsequently act on vascular physiology. In this paper, we summarize the recent literature data related to the effects of insulin, estradiol, insulin-like growth factor-1, ghrelin, angiotensin II and irisin on the NO regulation in physiological and diabetes circumstances.

Challenging the Norm: The Unrecognized Impact of Soluble Guanylyl Cyclase Subunits in Cancer

Since the discovery of nitric oxide (NO), a long journey has led us to the present, during which much knowledge has been gained about its pathway members and their roles in physiological and various pathophysiological conditions. Soluble guanylyl cyclase (sGC), the main NO receptor composed of the sGCα1 and sGCβ1 subunits, has been one of the central figures in this narrative. However, the sGCα1 and sGCβ1 subunits remained obscured by the focus on sGC's enzymatic activity for many years. In this review, we restore the significance of the sGCα1 and sGCβ1 subunits by compiling and analyzing available but previously overlooked information regarding their roles beyond enzymatic activity. We delve into the basics of sGC expression regulation, from its transcriptional regulation to its interaction with proteins, placing particular emphasis on evidence thus far demonstrating the actions of each sGC subunit in different tumor models. Exploring the roles of sGC subunits in cancer offers a valuable opportunity to enhance our understanding of tumor biology and discover new therapeutic avenues.

Mesenchymal stem cells improve cardiac function in diabetic rats by reducing cardiac injury biomarkers and downregulating JAK/STAT/iNOS and iNOS/Apoptosis signaling pathways

Cardiovascular complications are prevalent manifestations of type 2 diabetes mellitus (T2DM) and are usually the main cause of death. This study aims to show the underlying mechanisms of the potential therapeutic effect of mesenchymal stem cells (MSCs) on diabetic cardiac dysfunction. Twenty-four male Wistar rats were randomly assigned to one of three groups The control group received standard laboratory chow, and the groups with T2DM received a single dose of 45 mg/kg body weight of streptozotocin (STZ) after 3 weeks of pretreatment with a high-fat diet (HFD). Eight weeks after the diagnosis of T2DM, rats were divided into two groups: the T2DM model group and the T2DM + MSCs group. BM-MSCs were administered systemically at 2 × 106 cells/rat doses. A Significant amelioration in Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) and dyslipidemia was noted 2 weeks post-administration of MSCs. Administration of MSCs improved dyslipidemia, the altered cardiac injury biomarkers (p ≤ 0.0001), downregulated Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)/inducible Nitric oxide synthase (iNOS) and iNOS/Apoptosis signaling pathways. This was associated with improved cardiac dysfunction (impaired left ventricular performance and decreased contractility index). Our results show that MSCs ameliorate cardiac dysfunction associated with diabetic cardiomyopathy by lowering dyslipidemia and insulin resistance, inhibiting oxidative stress, and inflammation, downregulating JAK2/STAT3/iNOS and iNOS/Apoptosis signaling pathways.

Pathogenic Mechanisms That May Link Periodontal Disease and Type 2 Diabetes Mellitus-The Role of Oxidative Stress

Given the posited role of oxidative stress in the pathogenesis of both periodontitis and type 2 diabetes mellitus (T2DM), it may also serve as a link between these highly prevalent chronic inflammatory diseases. This view is supported by an ample body of evidence indicating that the severity and progression of periodontitis is in part driven by diabetes, while periodontal infection may hinder the attainment of adequate glycemic control in diabetic patients. Thus, this review focuses on the potential synergistic interactions along the oxidative stress-inflammation pathway characterizing both conditions. Because periodontitis and T2DM share the same risk factors and compromise patients' quality of life, to develop effective strategies for combatting both conditions, their mutual influence needs to be explored.

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.

N6-methyladenine RNA methylation epigenetic modification and diabetic microvascular complications

N6-methyladensine (m6A) has been identified as the best-characterized and the most abundant mRNA modification in eukaryotes. It can be dynamically regulated, removed, and recognized by its specific cellular components (respectively called "writers," "erasers," "readers") and have become a hot research field in a variety of biological processes and diseases. Currently, the underlying molecular mechanisms of m6A epigenetic modification in diabetes mellitus (DM) and diabetic microvascular complications have not been extensively clarified. In this review, we focus on the effects and possible mechanisms of m6A as possible potential biomarkers and therapeutic targets in the treatment of DM and diabetic microvascular complications.

Heparin-binding epidermal growth factor-like growth factor improves erectile function in streptozotocin-induced diabetic mice

BACKGROUND

Heparin-binding epidermal growth factor-like growth factor (HB-EGF) serves as a pro-angiogenic factor; however, there is to our knowledge currently no reported research on the relationship between HB-EGF and diabetic erectile dysfunction (ED).

AIM

In this study we aimed to determine whether HB-EGF can improve the erectile function of streptozotocin-induced diabetic mice and to explore the related mechanisms.

METHODS

Eight-week-old male C57BL/6 mice were used for diabetes induction. Diabetes mellitus (DM) was induced by low-dose injections of streptozotocin (50 mg/kg) for 5 consecutive days. Eight weeks after streptozotocin injections, DM was determined by measuring blood glucose and body weight. Diabetic mice were treated with two intracavernous administrations of phosphate-buffered saline (20 μL) or various doses of HB-EGF (days -3 and 0; 1, 5, and 10 μg in 20 μL of phosphate-buffered saline). The angiogenesis effect of HB-EGF was confirmed by tube formation and migration assays in mouse cavernous endothelial cells and mouse cavernous pericytes under high-glucose conditions. Erectile function was measured by electrical stimulation of the cavernous nerve, as well as histological examination and Western blot analysis for mechanism assessment.

OUTCOMES

In vitro angiogenesis, cell proliferation, in vivo intracavernous pressure, neurovascular regeneration, cavernous permeability, and survival signaling were the outcomes measured.

RESULTS

Expression of HB-EGF was reduced under diabetic conditions. Exogenous HB-EGF induced angiogenesis in mouse cavernous endothelial cells and mouse cavernous pericytes under high-glucose conditions. Erectile function was decreased in the DM group, whereas administration of HB-EGF resulted in a significant improvement of erectile function (91% of the age-matched control group) in association with increased neurovascular content, including cavernous endothelial cells, pericytes, and neuronal cells. Histological and Western blot analyses revealed a significant increase in the permeability of the corpus cavernosum in DM mice, which was attenuated by HB-EGF treatment. The protein expression of phospho-Akt Ser473 and phosphorylated endothelial nitric oxide synthase Ser1177 increased after HB-EGF treatment.

CLINICAL IMPLICATIONS

The use of HB-EGF may be an effective strategy to treat ED associated with DM or other neurovascular diseases.

STRENGTHS AND LIMITATIONS

Similarly to other pro-angiogenic factors, HB-EGF has dual roles in vascular and neuronal development. Our study focused on broadly evaluating the role of HB-EGF in diabetic ED. In view of the properties of HB-EGF as an angiogenic factor, its dose concentration should be strictly controlled to avoid potential side effects.

CONCLUSION

In the diabetic ED mouse model in this study erectile function was improved by HB-EGF, which may provide new treatment strategies for patients with ED who do not respond to phosphodiesterase 5 Inhibitors.

Vascular endothelial function and its response to moderate-intensity aerobic exercise in trained and untrained healthy young men

30 min of moderate-intensity aerobic exercise per day is recommended, but the response and adaptation of endothelial function (EF) to this exercise remains controversial. The purpose of this study was to determine the changes in EF in endurance trained and untrained individuals before and after this exercise and to compare the differences between trained and untrained individuals. Twelve endurance-trained male college athletes (trained group) and 12 untrained male college students (untrained group) performed a 30-min run at an intensity of 60% VO2max. Brachial artery flow-mediated dilation (FMD) was measured before exercise, 30 min and 60 min after exercise, and the following morning. Resting diameter and maximum diameter showed large time effects (p < 0.001, η2 = 0.533; p < 0.001, η2 = 0.502). Resting diameters at 30 and 60 min after exercise were higher than before exercise in both the untrained and trained groups (p < 0.05), and maximum diameters at 30 min after exercise were higher than before exercise in both the untrained and trained groups (p < 0.01). Resting diameter and maximum diameter also exhibited some group effects (p = 0.055, η2 = 0.157; p = 0.041, η2 = 0.176). Resting diameters and maximum diameters were higher in the trained group than in the untrained group before exercise (p < 0.05). FMD (%) showed no time, group, or time-group interaction effects. 30 min of moderate-intensity aerobic exercise can increase resting and maximal arterial diameters in both trained and untrained young men, but has no effect on FMD. Long-term endurance training has the potential to increase resting and maximal arterial diameters in young men, but not necessarily FMD.

Combining functional and morphological retinal vascular characteristics achieves high-precision diagnosis of mild non-proliferative diabetic retinopathy

BACKGROUND

To explore the functional and morphological variations of retinal vessels in diabetes with no clinically detectable retinopathy (NDR) and mild non-proliferative diabetic retinopathy (NPDR) and to establish a high-performance mild NPDR diagnostic model.

METHODS

Normal subjects and type 2 diabetes patients with NDR and mild NPDR were recruited. Oxygen-saturation-related functional parameter (optical density ratio ODR) and morphological characteristics (fractal dimension Df, vessel area rate VAR, mean vascular diameter Dm, vessel tortuosity τ) of different vascular areas were extracted with single fundus photography and comprehensively analyzed among groups. An interpretable model combining marine predator algorithm (MPA) and support vector machine (SVM) based on characteristic selection was proposed for mild NPDR diagnosis.

RESULTS

A total of 91 NDR subjects, 75 mild NPDR subjects, and 111 sex- and age-matched normal controls were analyzed. Increased main vessels ODR, while lower VAR of all areas except outer ring macula, lower Dm of all vessels and decreased τ of all areas were associate with NDR (e.g. main vessels ODR: OR [95%CI] 1.42[1.07-1.89], full macula τ:0.53[0.38-0.74]). Increased ODR of all areas, higher Dm of all areas except inner ring macula, increased inner ring macula τ, while decreased Df of full and inner ring macula, lower VAR of all areas were associate with mild NPDR (e.g. main vessels ODR:5.68[3.03-10.65], inner ring macula VAR: 0.48[0.33-0.69]). The MPA-SVM model with selected characteristics obtained the best diagnosis performance (AUC:0.940 ± 0.014; Accuracy:90.4 ± 3.9%; Sensitivity:89.2 ± 6.4%; Specificity:91.3 ± 6.4%).

CONCLUSIONS

More significant retinal vascular variations are associate with the incidence of mild NPDR than NDR. High-precision mild NPDR diagnosis is achieved combining the morphological and functional vascular characteristics based on characteristic selection.

Protein tyrosine phosphatase 1B in metabolic and cardiovascular diseases: from mechanisms to therapeutics

Protein Tyrosine Phosphatase 1B (PTP1B) has emerged as a significant regulator of metabolic and cardiovascular disease. It is a non-transmembrane protein tyrosine phosphatase that negatively regulates multiple signaling pathways integral to the regulation of growth, survival, and differentiation of cells, including leptin and insulin signaling, which are critical for development of obesity, insulin resistance, type 2 diabetes, and cardiovascular disease. Given PTP1B's central role in glucose homeostasis, energy balance, and vascular function, targeted inhibition of PTP1B represents a promising strategy for treating these diseases. However, challenges, such as off-target effects, necessitate a focus on tissue-specific approaches, to maximize therapeutic benefits while minimizing adverse outcomes. In this review, we discuss molecular mechanisms by which PTP1B influences metabolic and cardiovascular functions, summarize the latest research on tissue-specific roles of PTP1B, and discuss the potential for PTP1B inhibitors as future therapeutic agents.

Endothelin-1 (ET-1) contributes to senescence and phenotypic changes in brain pericytes in diabetes-mimicking conditions

Diabetes mediates endothelial dysfunction and increases the risk of Alzheimer's disease and related dementias. Diabetes also dysregulates the ET system. ET-1-mediated constriction of brain microvascular pericytes (BMVPCs) has been shown to contribute to brain hypoperfusion. Cellular senescence, a process that arrests the proliferation of harmful cells and instigates phenotypical changes and proinflammatory responses in endothelial cells that impact their survival and function. Thus, we hypothesized that ET-1 mediates BMVPC senescence and phenotypical changes in diabetes-like conditions. Human BMVPCs were incubated in diabetes-like conditions with or without ET-1 (1 µmol/L) for 3 and 7 days. Hydrogen peroxide (100 µmol/L H2O2) was used as a positive control for senescence and to mimic ischemic conditions. Cells were stained for senescence-associated β-galactosidase or processed for immunoblotting and quantitative real-time PCR analyses. In additional experiments, cells were stimulated with ET-1 in the presence or absence of ETA receptor antagonist BQ-123 (20 μmol/L) or ETB receptor antagonist BQ-788 (20 μmol/L). ET-1 stimulation increased β-galactosidase accumulation which was prevented by BQ-123. ET-1 also increased traditional senescence marker p16 protein and pericyte-specific senescence markers, TGFB1i1, PP1CA, and IGFBP7. Furthermore, ET-1 stimulated contractile protein α-SMA and microglial marker ostepontin in high glucose suggesting a shift toward an ensheathing or microglia-like phenotype. In conclusion, ET-1 triggers senescence, alters ETA and ETB receptors, and causes phenotypical changes in BMVPCs under diabetes-like conditions. These in vitro findings need to be further studied in vivo to establish the role of ETA receptors in the progression of pericyte senescence and phenotypical changes in VCID.

Diabetic Foot and Fungal Infections: Etiology and Management from a Dermatologic Perspective

Diabetes Mellitus (DM) is a significant global concern. Many diabetic patients will experience complications due to angiopathy, neuropathy, and immune dysfunction, namely diabetic foot ulcers (DFU) and diabetic foot infections (DFI), which can result in lower limb amputation and potentially death. The prevalence of common superficial fungal infections, such as tinea pedis and onychomycosis, can directly increase a diabetic patient's risk of developing both DFU and DFI. In this review article, we discuss the etiology of diabetic foot complications as well as considerations for both screening and management. We also discuss the role of the dermatologist within a multidisciplinary care team in prescribing and managing treatments for tinea pedis and onychomycosis infections within this patient population. We believe that reducing the burden of these fungal infections in the context of the diabetic foot will help reduce DFU and DFI complications and their associated morbidity and mortality.

Transcapillary PO2 Gradients in Contracting Muscles of Type I Diabetic Rats

OBJECTIVE

This study aimed to clarify the effect of Type I diabetes (DIA) on transcapillary PO2 gradients, which are oxygen-driving factors between the blood and the interstitium, in the contracting muscle of rats.

METHODS

Wistar male rats were divided into the diabetic (streptozocin i.p.) and sham groups. Microvascular and interstitial PO2 were measured in the extensor digitorum longus muscle during electrical stimulation-induced muscle contraction, using the phosphorescence quenching method. Transcapillary PO2 gradient, ΔPO2, was calculated as microvascular minus interstitial PO2.

RESULTS

Resting microvascular PO2 was higher in the diabetic group than in the sham group (6.3 ± 1.7 vs. 4.7 ± 0.9 mmHg, p < 0.05) and remained for 180 s. Interstitial PO2 from rest to muscle contraction did not differ between the groups. The ΔPO2 was higher in the diabetic group than in the sham group at rest and during muscle contraction (4.03 ± 1.42 vs. 2.46 ± 0.90 mmHg at rest; 3.67 ± 1.51 vs. 2.22 ± 0.65 mmHg during muscle contraction, p < 0.05). Marked muscle atrophy was observed in the diabetic group.

CONCLUSION

DIA increased microvascular and transcapillary PO2 gradients in the skeletal muscle. The enhanced PO2 gradients were maintained from rest to muscle contraction in diabetic muscle.

Impact of gestational diabetes mellitus on neonatal outcomes in small for gestational age infants: a multicenter retrospective study

OBJECTIVE

To evaluate obstetric and perinatal outcomes among small for gestational age (SGA) infants born to patients diagnosed with Gestational diabetes mellitus (GDM).

MATERIALS AND METHODS

A multicenter retrospective cohort study between 2005 and 2021. The perinatal outcomes of SGA infants born to patients with singleton pregnancy and GDM were compared to SGA infants born to patients without GDM. The primary outcome was a composite adverse neonatal outcome. Infants with known structural/genetic abnormalities or infections were excluded. A univariate analysis was conducted followed by a multivariate analysis (adjusted odds ratio [95% confidence interval]).

RESULTS

During the study period, 11,662 patients with SGA infants met the inclusion and exclusion criteria. Of these, 417 (3.6%) SGA infants were born to patients with GDM, while 11,245 (96.4%) were born to patients without GDM. Overall, the composite adverse neonatal outcome was worse in the GDM group (53.7% vs 17.4%, p < 0.01). Specifically, adverse neonatal outcomes such as a 5 min Apgar score < 7, meconium aspiration, seizures, and hypoglycemia were independently associated with GDM among SGA infants. In addition, patients with GDM and SGA infants had higher rates of overall and spontaneous preterm birth, unplanned cesarean, and postpartum hemorrhage. In a multivariate logistic regression assessing the association between GDM and neonatal outcomes, GDM was found to be independently associated with the composite adverse neonatal outcome (aOR 4.26 [3.43-5.3]), 5 min Apgar score < 7 (aOR 2 [1.16-3.47]), meconium aspiration (aOR 4.62 [1.76-12.13]), seizures (aOR 2.85 [1.51-5.37]) and hypoglycemia (aOR 16.16 [12.79-20.41]).

CONCLUSIONS

Our study demonstrates that GDM is an independent risk factor for adverse neonatal outcomes among SGA infants. This finding underscores the imperative for tailored monitoring and management strategies in those pregnancies.

Endothelial dysfunction: molecular mechanisms and clinical implications

Cardiovascular disease (CVD) and its complications are a leading cause of death worldwide. Endothelial dysfunction plays a crucial role in the initiation and progression of CVD, serving as a pivotal factor in the pathogenesis of cardiovascular, metabolic, and other related diseases. The regulation of endothelial dysfunction is influenced by various risk factors and intricate signaling pathways, which vary depending on the specific disease context. Despite numerous research efforts aimed at elucidating the mechanisms underlying endothelial dysfunction, the precise molecular pathways involved remain incompletely understood. This review elucidates recent research findings on the pathophysiological mechanisms involved in endothelial dysfunction, including nitric oxide availability, oxidative stress, and inflammation-mediated pathways. We also discuss the impact of endothelial dysfunction on various pathological conditions, including atherosclerosis, heart failure, diabetes, hypertension, chronic kidney disease, and neurodegenerative diseases. Furthermore, we summarize the traditional and novel potential biomarkers of endothelial dysfunction as well as pharmacological and nonpharmacological therapeutic strategies for endothelial protection and treatment for CVD and related complications. Consequently, this review is to improve understanding of emerging biomarkers and therapeutic approaches aimed at reducing the risk of developing CVD and associated complications, as well as mitigating endothelial dysfunction.

Association between oxidative balance score and diabetic kidney disease, low estimated glomerular filtration rate and albuminuria in type 2 diabetes mellitus patients: a cross-sectional study

Objective

The oxidative balance score (OBS) is a comprehensive concept that includes 20 oxidative stressors and can be used to assess individual pro-oxidant versus antioxidant exposure, and the aim of the present study was to investigate the association between OBS and the risk of diabetic kidney disease (DKD), low estimated glomerular filtration rate (low-eGFR) and albuminuria in patients with diabetes mellitus (DM).

Methods

This cross-sectional study included nationally representative consecutive National Health and Nutrition Examination Survey DM patients aged 18 years and older from 2003-2018. The continuous variable OBS was converted into categorical variables by quartiles, and weighted multiple logistic regression analyses and restricted triple spline models were used to explore the relationships. We also performed subgroup analyses and interaction tests to verify the stability of the results.

Results

A total of 5389 participants were included, representing 23.6 million non-institutionalized US residents. The results from both multivariate logistic regression analysis and restricted cubic spline models indicated that OBS and dietary OBS levels were negatively associated with the risk of DKD, low-eGFR, and albuminuria, without finding a significant correlation between lifestyle OBS and these clinical outcomes. Compared to the lowest OBS quartile group, the prevalence risk of DKD (OR = 0.61, 95% CI: 0.46-0.80), low-eGFR (OR = 0.46, 95% CI: 0.33-0.64) and albuminuria (OR = 0.68, 95% CI: 0.51-0.92) decreased by 39%, 54% and 32%, respectively, in the highest OBS quartile group. The results remained stable in subgroup analyses and no interaction between subgroups was found.

Conclusion

Higher levels of OBS and dietary OBS were associated with a lower risk of DKD, low-eGFR, and albuminuria. These findings provided preliminary evidence for the importance of adhering to an antioxidant-rich diet and lifestyle among individuals with diabetes.

Cellular Components of the Blood-Brain Barrier and Their Involvement in Aging-Associated Cognitive Impairment

Human life expectancy has been significantly extended, which poses major challenges to our healthcare and social systems. Aging-associated cognitive impairment is attributed to endothelial dysfunction in the cardiovascular system and neurological dysfunction in the central nervous system. The central nervous system is considered an immune-privileged tissue due to the exquisite protection provided by the blood-brain barrier. The present review provides an overview of the structure and function of blood-brain barrier, extending the cell components of blood-brain barrier from endothelial cells and pericytes to astrocytes, perivascular macrophages and oligodendrocyte progenitor cells. In particular, the pathological changes in the blood-brain barrier in aging, with special focus on the underlying mechanisms and molecular changes, are presented. Furthermore, the potential preventive/therapeutic strategies against aging-associated blood-brain barrier disruption are discussed.

From waste to wonder: exploring the hypoglycemic and anti-oxidant properties of corn processing by-products

Introduction: The industrial processing of corn (Zeamays L.) generates by-products such as corn silk, straw peels, and straw core, which contribute to adverse environmental impacts. Our study aimed to investigate sustainable approaches for mitigating these effects by evaluating the hypoglycemic potential and mechanisms of ethyl acetate fractions derived from these corn derivatives. Methods: We employed glucose consumption assays, high glucose stress tests, UPLC-QE-Orbitrap-MS analysis, molecular docking, and simulations to assess their components and efficacy. Antioxidant capacities were evaluated using DPPH, FRAP, ABTS, and •OH scavenging assays. Results: Notably, the ethyl acetate fraction extracted from straw peels (SPE) exhibited a high concentration of flavonoids and phenolic compounds along with pronounced hypoglycemic activity and antioxidant capacity. SPE significantly enhanced glucose consumption in insulin-resistant HepG2 cells while protecting HUVECs against damage caused by high glucose levels. Molecular docking analyses confirmed the interaction between active compounds and α-glucosidase as well as α-amylase, while molecular dynamic simulations indicated stability at their binding sites. Discussion: In conclusion, the hypoglycemic and antioxidative properties observed in corn by-products such as straw peels, corn silk, and straw core can be attributed to the inhibition of α-glucosidase and α-amylase activities, coupled with their rich phenolic and flavonoid content. These findings highlight the potential of these by-products for applications in healthcare management and their sustainable utilization, demonstrating significant value in the use of agricultural residues.

Prevalence and risk factors of retinal vein occlusion in individuals with diabetes: The kailuan eye study

PURPOSE

The aim of this study was to analyze the incidence of retinal vein occlusion (RVO) in patients with and without diabetes in the population and compare the influencing factors.

METHOD

The community-based Kailuan Eye Study included 14,440 participants (9835 male, 4605 female) with a mean age of 54.0 ± 13.3 years (range, 20-110 years). They underwent a systemic and ophthalmologic examination. RVO were diagnosed on fundus photographs.

RESULT

By matching for age and gender, we included a total of 2767 patients each with diabetes and non-diabetes. The prevalence of RVO among patients with and without diabetes was 1.5% and 0.8%, respectively. The prevalence of RVO was higher in patients with diabetes than in patients without diabetes in all age groups. Multifactorial regression analysis showed that only fasting blood glucose levels were significantly different between patients with RVO with or without DM. The occurrence of RVO in the group with diabetes was mainly associated with higher fasting glucose and systolic blood pressure; in the group without diabetes, RVO was mainly associated with higher diastolic blood pressure, Body Mass Index, and lower low-density lipoprotein cholesterol levels.

CONCLUSION

We found that patients with diabetes have increased risks of RVO. In addition to blood pressure control, we recommend educating patients with diabetes about RVO, to prevent its subsequent occurrence.

Preconditioning Local Injection of Activated Platelet-Rich Plasma Increases Angiogenesis, VEGF Levels, and Viability of Modified McFarlane Flap in Diabetes-Induced Rats

Background  The risk of flap necrosis in tissue reconstruction surgery is elevated in patients with vascular disorders, such as diabetes mellitus. Chronic hyperglycemia causes endothelial cell dysfunction and increases inflammatory process, causing vascular insufficiency. Platelet-rich plasma (PRP) contains high levels of platelets, growth factors, and fibrinogens. Its regenerative properties spark interest in supporting flap survival in relation to diabetic complications. Methods  Thirty Wistar rats were divided into three groups. The first group included diabetic rats without PRP injection, which underwent flap procedure. The second group included diabetes-induced rats receiving PRP subcutaneous injection 1 day prior to flap procedure. The third group included nondiabetic rats receiving PRP injection 1 day prior to flap procedure. Flap tissue samples were taken on the seventh day to measure vascular endothelial growth factor (VEGF) levels using enzyme-linked immunosorbent assay method; angiogenesis and collagen density were measured from histopathology examination, and flap viability was analyzed using digital measurements. Results  Analysis showed that flap viability, angiogenesis, and VEGF levels were significantly higher in the PRP-injected diabetic rats compared with diabetic rats that did not receive PRP. The levels of VEGF, angiogenesis, and viability of flaps in diabetic rats given PRP did not differ significantly compared with nondiabetic rats that received PRP. Conclusion  Flap preconditioning through local injection of activated PRP enhances flap viability, VEGF levels and angiogenesis, in random skin flaps in diabetic rats, to the level where it does not differ significantly to nondiabetic rats that were given PRP.

Nanoparticle-mediated delivery of tetrahydrobiopterin restores endothelial function in diabetic rats

Endothelial dysfunction, underlying the vascular complications of diabetes and other cardiovascular disorders, may result from uncoupling of endothelial nitric oxide synthase (eNOS) activity due to decreased levels of tetrahydrobiopterin (BH4), a critical co-factor for eNOS. Some clinical trials attempting to deliver exogenous BH4 as a potential therapeutic strategy in vascular disease states have failed due to oxidation of BH4 in the circulation. We sought to develop a means of protecting BH4 from oxidation while delivering it to dysfunctional endothelial cells. Polymeric and solid lipid nanoparticles (NPs) loaded with BH4 were delivered by injection or oral gavage, respectively, to streptozotocin-induced diabetic rats. BH4 was measured in coronary endothelial cells and endothelium-dependent vascular reactivity was assessed in vascular rings. Lymphatic uptake of orally delivered lipid NPs was verified by sampling mesenteric lymph. BH4-loaded polymeric NPs maintained nitric oxide production by cultured endothelial cells under conditions of oxidative stress. BH4-loaded NPs, delivered via injection or ingestion, increased coronary endothelial BH4 concentration and improved endothelium-dependent vasorelaxation in diabetic rats. Pharmacodynamics assessment indicated peak concentration of solid lipid NPs in the systemic bloodstream 6 hours after ingestion, with disappearance noted by 48 hours. These studies support the feasibility of utilizing NPs to deliver BH4 to dysfunctional endothelial cells to increase nitric oxide bioavailability. BH4-loaded NPs could provide an innovative tool to restore redox balance in blood vessels and modulate eNOS-mediated vascular function to reverse or retard vascular disease in diabetes.

New insights into the roles of Irisin in diabetic cardiomyopathy and vascular diseases

Diabetes mellitus (DM) is a prevalent chronic disease in the 21st century due to increased lifespan and unhealthy lifestyle choices. Extensive research indicates that exercise can play a significant role in regulating systemic metabolism by improving energy metabolism and mitigating various metabolic disorders, including DM. Irisin, a well-known exerkine, was initially reported to enhance energy expenditure by indicating the browning of white adipose tissue (WAT) through peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) signaling. In this review, we summarize the potential mechanisms underlying the beneficial effects of Irisin on glucose dysmetabolism, including reducing gluconeogenesis, enhancing insulin energy expenditure, and promoting glycogenesis. Additionally, we highlight Irisin's potential to improve diabetic vascular diseases by stimulating nitric oxide (NO) production, reducing oxidative and nitrosative stress, curbing inflammation, and attenuating endothelial cell aging. Furthermore, we discuss the potential of Irisin to improve diabetic cardiomyopathy by preventing cardiomyocyte loss and reducing myocardial hypertrophy and fibrosis. Given Irisin's promising functions in managing diabetic cardiomyopathy and vascular diseases, targeting Irisin for therapeutic purposes could be a fruitful avenue for future research and clinical interventions.

Effects of Empagliflozin in Type 2 Diabetes With and Without Chronic Kidney Disease and Nondiabetic Chronic Kidney Disease: Protocol for 3 Crossover Randomized Controlled Trials (SiRENA Project)

BACKGROUND

Sodium-glucose-cotransporter 2 inhibitors (SGLT2is) have revolutionized the treatment of type 2 diabetes mellitus (DM2) and chronic kidney disease (CKD), reducing the risk of cardiovascular and renal end points by up to 40%. The underlying mechanisms are not fully understood.

OBJECTIVE

The study aims to examine the effects of empagliflozin versus placebo on renal hemodynamics, sodium balance, vascular function, and markers of the innate immune system in patients with DM2, DM2 and CKD, and nondiabetic CKD.

METHODS

We conducted 3 double-blind, crossover, randomized controlled trials, each with identical study protocols but different study populations. We included patients with DM2 and preserved kidney function (estimated glomerular filtration rate >60 mL/min/1.73 m2), DM2 and CKD, and nondiabetic CKD (both with estimated glomerular filtration rate 20-60 mL/min/1.73 m2). Each participant was randomly assigned to 4 weeks of treatment with either 10 mg of empagliflozin once daily or a matching placebo. After a wash-out period of at least 2 weeks, participants were crossed over to the opposite treatment. End points were measured at the end of each treatment period. The primary end point was renal blood flow measured with 82Rubidium positron emission tomography-computed tomography (82Rb-PET/CT). Secondary end points include glomerular filtration rate measured with 99mTechnetium-diethylene-triamine-pentaacetate (99mTc-DTPA) clearance, vascular function assessed by forearm venous occlusion strain gauge plethysmography, measurements of the nitric oxide (NO) system, water and sodium excretion, body composition measurements, and markers of the complement immune system.

RESULTS

Recruitment began in April 2021 and was completed in September 2022. Examinations were completed by December 2022. In total, 49 participants completed the project: 16 participants in the DM2 and preserved kidney function study, 17 participants in the DM2 and CKD study, and 16 participants in the nondiabetic CKD study. Data analysis is ongoing. Results are yet to be published.

CONCLUSIONS

This paper describes the rationale, design, and methods used in a project consisting of 3 double-blind, crossover, randomized controlled trials examining the effects of empagliflozin versus placebo in patients with DM2 with and without CKD and patients with nondiabetic CKD, respectively.

TRIAL REGISTRATION

EU Clinical Trials Register 2019-004303-12; https://www.clinicaltrialsregister.eu/ctr-search/search?query=2019-004303-12, EU Clinical Trials Register 2019-004447-80; https://www.clinicaltrialsregister.eu/ctr-search/search?query=2019-004447-80, EU Clinical Trials Register 2019-004467-50; https://www.clinicaltrialsregister.eu/ctr-search/search?query=and+2019-004467-50.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/56067.

Advanced Mass Spectrometry-Based Biomarker Identification for Metabolomics of Diabetes Mellitus and Its Complications

Over the years, there has been notable progress in understanding the pathogenesis and treatment modalities of diabetes and its complications, including the application of metabolomics in the study of diabetes, capturing attention from researchers worldwide. Advanced mass spectrometry, including gas chromatography-tandem mass spectrometry (GC-MS/MS), liquid chromatography-tandem mass spectrometry (LC-MS/MS), and ultra-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-Q-TOF-MS), etc., has significantly broadened the spectrum of detectable metabolites, even at lower concentrations. Advanced mass spectrometry has emerged as a powerful tool in diabetes research, particularly in the context of metabolomics. By leveraging the precision and sensitivity of advanced mass spectrometry techniques, researchers have unlocked a wealth of information within the metabolome. This technology has enabled the identification and quantification of potential biomarkers associated with diabetes and its complications, providing new ideas and methods for clinical diagnostics and metabolic studies. Moreover, it offers a less invasive, or even non-invasive, means of tracking disease progression, evaluating treatment efficacy, and understanding the underlying metabolic alterations in diabetes. This paper summarizes advanced mass spectrometry for the application of metabolomics in diabetes mellitus, gestational diabetes mellitus, diabetic peripheral neuropathy, diabetic retinopathy, diabetic nephropathy, diabetic encephalopathy, diabetic cardiomyopathy, and diabetic foot ulcers and organizes some of the potential biomarkers of the different complications with the aim of providing ideas and methods for subsequent in-depth metabolic research and searching for new ways of treating the disease.

Design, synthesis, and evaluation of novel ferrostatin derivatives for the prevention of HG-induced VEC ferroptosis

Ferroptosis is a nonapoptotic, iron-catalyzed form of regulated cell death. It has been shown that high glucose (HG) could induce ferroptosis in vascular endothelial cells (VECs), consequently contributing to the development of various diseases. This study synthesized and evaluated a series of novel ferrostatin-1 (Fer-1) derivatives fused with a benzohydrazide moiety to prevent HG-induced VEC ferroptosis. Several promising compounds showed similar or improved inhibitory effects compared to positive control Fer-1. The most effective candidate 12 exhibited better protection against erastin-induced ferroptosis and high glucose-induced ferroptosis in VECs. Mechanistic studies revealed that compound 12 prevented mitochondrial damage, reduced intracellular ROS accumulation, upregulated the expression of GPX4, and decreased the amounts of ferrous ion, LPO and MDA in VECs. However, compound 12 still exhibited undesirable microsomal stability like Fer-1, suggesting the need for further optimization. Overall, the present findings highlight ferroptosis inhibitor 12 as a potential lead compound for treating ferroptosis-associated vascular diseases.