The association of cell adhesion molecules and selectins (VCAM-1, ICAM-1, E-selectin, L-selectin, and P-selectin) with microvascular complications in patients with type 2 diabetes: A follow-up study

Molecular basis of cardioprotective effects of methanol extract of Ficus exasperata in diabetic Wistar rats

Cardiovascular complications are a significant concern in diabetes mellitus. Ficus exasperata Vahl leaf has been traditionally used for diabetes management, yet its impact on cardiovascular biomarkers in diabetic conditions remains unexplored. This study evaluated the effects of methanol extract of Ficus exasperata (MEFE) on antioxidant defense, oxidative stress markers, ion transport enzymes, inflammatory mediators, and cardiovascular gene expression in diabetic Wistar rats. Twenty Wistar rats were divided into four groups (n = 5): control, diabetic untreated, diabetes + MEFE (200 mg/kg), and diabetes + insulin (0.3 IU). Diabetes was induced with alloxan monohydrate (150 mg/kg), and treatments were administered orally for 28 days. Antioxidant enzyme activities (Glutathione peroxidase (GPx), Glutathione reductase (GR), Superoxide dismutase (SOD), Catalase, malondialdehyde and 8-hydroxy-2'-deoxyguanosine), Cardiac biomarkers (Na+/K+ ATPase, Ca2+ ATPase, Creatinine kinase-myocardial band (CK-MB), Troponin I, Troponin T, and Lactatate dehydrogenase), and gene expression of CRP, ACE, P-Selectin, and eNOS were evaluated. Data were analyzed using one-way analysis of variance, expressed as mean ± SEM, and p < 0.05 was considered statistically significant. The diabetic group treated with MEFE (200 mg/kg) significantly increased Ca²⁺ ATPase, SOD, and glutathione reductase activities compared to diabetic untreated. However, malondialdehyde and 8-OHdG levels decreased significantly in diabetes+MEFE (200 mg/kg) compared to diabetes untreated. CK-MB levels increased significantly in diabetes+MEFE (200 mg/kg) compared to diabetic untreated. MEFE reduced ACE and P-selectin expression in diabetes+MEFE (200 mg/kg) compared to diabetic untreated, indicating potential antihypertensive and anti-thrombotic effects. However, it increased CRP levels compared to control, suggesting an inflammatory response. MEFE significantly reduced eNOS expression compared to diabetic untreated, suggesting impaired vascular function. These findings suggest that while Ficus exasperata has some beneficial effects, its impact on inflammatory and cardiac biomarkers necessitates further research to fully understand its therapeutic potential and safety.

The effects of the mediterranean diet supplemented with olive oils on pro-inflammatory biomarkers and soluble adhesion molecules: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Inflammation plays a pivotal role in Cardiovascular disease (CVD) which are a major global health burden. The oil-supplemented Mediterranean diet (MED) is associated with anti-inflammatory effects. The current study evaluates the impact of an olive oils-supplemented MED on pro-inflammatory biomarkers and soluble adhesion molecules.

METHODS

Regarding PRISMA guideline, this study was conducted and PubMed, Scopus, Web of Science (ISI), Embase, CINAHL databases as well as Google Scholar and Cochrane Library were systematically searched till June 2024.

RESULTS

15 clinical trials (20 arms) comprising 2477 adults aged 23-80 years were included in the systematic review and 9 of them were entered in the meta-analysis. We revealed that following an enriched MED with olive oils can reduce Interleukin-6 (IL-6) (SMD: - 1.85; 95% CI: -3.69 to -0.01, I2: 99.29%) and c-reactive protein (CRP) or high-sensitivity CRP (hs-CRP) (SMD: - 0.96; 95% CI: -1.49 to -0.44, I2: 91.85%); however, tumor necrosis factor α (TNFα), monocyte chemoattractant protein-1 (MCP-1) and interferon gamma (IFN-γ) did not improved. Moreover, a positive impact on the levels of soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1) and P-selectin [(SMD: -2.37; 95% CI: -4.34 to -0.40, I2: 99.38%), (SMD: -1.10; 95% CI: -2.10 to -0.10, I2: 94.96%) and (SMD: -0.65; 95% CI: -1.18 to -0.12, I2: 59.33%), respectively] were observed; however, E-selectin was unchanged.

CONCLUSIONS

The olive oils-supplemented MED demonstrates significant anti-inflammatory benefits and improvements in soluble adhesion molecules, supporting its role in reducing CVD risk. However, further studies are required to address the high heterogeneity and confirm these findings in diverse populations.

TRIAL REGISTRATION/PROTOCOL REGISTRATION

PROSPERO (CRD42023425225).

Stromal Cell-Derived Factor-1, P-Selectin, and Advanced Oxidation Protein Products with Mitochondrial Dysfunction Concurrently Impact Cerebral Vessels in Patients with Normoalbuminuric Diabetic Kidney Disease and Type 2 Diabetes Mellitus

Diabetic kidney disease (DKD) displays a high prevalence of cardiovascular and cerebrovascular disease. Both the kidney and the brain share common pathogenic mechanisms, such as inflammation, endothelial dysfunction, oxidative stress, and mitochondrial dysfunction. The aim of this study was to establish a potential association of cerebral vessel remodeling and its related functional impairment with biomarkers of inflammation, oxidative stress, and mitochondrial dysfunction in the early stages of DKD in type 2 diabetes mellitus (DM) patients. A cohort of 184 patients and 39 healthy controls was assessed concerning serum and urinary stromal cell-derived factor-1 (SDF-1), P-selectin, advanced oxidation protein products (AOPPs), urinary synaptopodin, podocalyxin, kidney injury molecule-1 (KIM-1), and N-acetyl-β-(D)-glucosaminidase (NAG). The quantification of the mitochondrial DNA copy number (mtDNA-CN) and nuclear DNA (nDNA) in urine and peripheral blood was conducted using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Using TaqMan tests, the beta-2 microglobulin nuclear gene (B2M) and the cytochrome b (CYTB) gene, which encodes subunit 2 of NADH dehydrogenase (ND2), were evaluated. The MtDNA-CN is the ratio of mitochondrial DNA to nuclear DNA copies, ascertained through the examination of the CYTB/B2M and ND2/B2M ratios. The intima-media thickness (IMT) measurements of the common carotid arteries (CCAs), along with the pulsatility index (PI) and resistivity index (RI) of the internal carotid arteries (ICAs) and middle cerebral arteries (MCAs), were obtained through cerebral Doppler ultrasonography (US). Additionally, the breath-holding index (BHI) was also measured by cerebral Doppler US. PI-ICAs, PI-MCAs, CCAs-IMT, RI-MCAs, and RI-ICAs demonstrated direct relationships with SDF-1, P-selectin, AOPPs, urine mtDNA, podocalyxin, synaptopodin, NAG, and KIM-1 while showing indirect correlations with serum mtDNA and the eGFR. In contrast, the BHI had negative correlations with SDF-1, P-selectin, AOPPs, urine mtDNA, synaptopodin, podocalyxin, KIM-1, and NAG while showing direct associations with serum mtDNA and the eGFR. In conclusion, a causative association exists among SDF-1, P-selectin, and AOPPs, as well as mitochondrial dysfunction, in early diabetic kidney disease (DKD) and significant cerebrovascular alterations in patients with type 2 diabetes mellitus and normoalbuminuric DKD, with no neurological symptoms.

Epigenome-wide association study of incident type 2 diabetes in Black and White participants from the Atherosclerosis Risk in Communities Study

AIMS/HYPOTHESIS

DNA methylation studies of incident type 2 diabetes in US populations are limited and to our knowledge none include individuals of African descent. We aimed to fill this gap by identifying methylation sites (CpG sites) and regions likely influencing the development of type 2 diabetes using data from Black and White individuals from the USA.

METHODS

We prospectively followed 2091 Black and 1029 White individuals without type 2 diabetes from the Atherosclerosis Risk in Communities study over a median follow-up period of 17 years, and performed an epigenome-wide association analysis of blood-based methylation levels with incident type 2 diabetes using Cox regression. We assessed whether significant CpG sites were associated with incident type 2 diabetes independently of BMI or fasting glucose at baseline. We estimated variation in incident type 2 diabetes accounted for by the major non-genetic risk factors and the significant CpG sites. We also examined groups of methylation sites that were differentially methylated. We performed replication of previously discovered CpG sites associated with prevalent and/or incident type 2 diabetes. All analyses were adjusted for batch effects, cell-type proportions and relevant confounders.

RESULTS

At an epigenome-wide threshold (10-7), we detected seven novel diabetes-associated CpG sites, of which the sites at MICOS10 (cg05380846: HR 0.89, p=8.4 × 10-12), ZNF2 (cg01585592: HR 0.88, p=1.6 × 10-9), JPH3 (cg16696007: HR 0.87, p=7.8 × 10-9) and GPX6 (cg02793507: HR 0.85, p=2.7 × 10-8; cg00647063: HR 1.20, p=2.5 × 10-8) were identified in Black adults; chr17q25 (cg16865890: HR 0.8, p=6.9 × 10-8) in White adults; and chr11p15 (cg13738793: HR 1.11, p=7.7 × 10-8) in the meta-analysed group. The JPH3 and GPX6 sites remained epigenome-wide significant on adjustment for BMI, while only the JPH3 site retained significance after adjusting for fasting glucose. We replicated known type 2 diabetes-associated CpG sites, including cg19693031 at TXNIP, cg00574958 at CPT1A, cg16567056 at PLCB2, cg11024682 at SREBF1, cg08857797 at VPS25 and cg06500161 at ABCG1, three of which were replicated in Black adults at the epigenome-wide threshold and all of which had directionally consistent effects. We observed a modest increase in type 2 diabetes variance explained by the significantly associated CpG sites over and above traditional type 2 diabetes risk factors and fasting glucose (26.2% vs 30.5% in Black adults; 36.9% vs 39.4% in White adults). At the Šidák-corrected significance threshold of 5%, our differentially methylated region (DMR) analyses revealed several clusters of significant CpG sites, including a DMR consisting of a previously discovered CpG site at ADCY7 (pBlack=1.8 × 10-4, pWhite=3.6 × 10-3, pAll=1.6 × 10-9) and a DMR consisting of the promoter region of TP63 (pBlack=7.4 × 10-4, pWhite=3.9 × 10-3, pAll=1.4 × 10-5), which were differentially methylated across all racial and ethnic groups.

CONCLUSIONS/INTERPRETATION

This study illustrates improved discovery of CpG sites and regions by leveraging both individual CpG site analysis and DMR analyses in an unexplored population. Our findings include genes linked to diabetes in experimental studies (e.g. GPX6, JPH3 and TP63). The JPH3 and GPX6 sites were likely associated with incident type 2 diabetes independently of BMI. All the CpG sites except that at JPH3 were likely consequences of elevated glucose. Replication in African-descent individuals of CpG sites previously discovered mostly in individuals of European descent indicates that some of these methylation-type 2 diabetes associations are robust across racial and ethnic groups. This study is a first step towards understanding the influence of methylation on the incidence of type 2 diabetes and its disparity in two major racial and ethnic groups in the USA. It paves the way for future studies to investigate causal relationships between type 2 diabetes and the CpG sites and potentially elucidate molecular targets for intervention.

Assessment of nerve conduction velocity slowing and its association with the severity of diabetic polyneuropathy, duration of diabetes and glycemic control in diabetic patients

Objective

This study aimed to investigate the nerve conduction velocity in diabetic patients and its association with diabetes duration, control and severity of diabetic polyneuropathy.

Methods

This prospective, observational study involved a hundred and thirty-nine patients who underwent nerve conduction studies in the Neurology Department at Liaquat National Hospital during the years June 2023 till May 2024. In all patients, the medical history was taken by direct interview regarding demographics, diabetes duration and recent HbA1c. For the assessment of diabetic polyneuropathy, the NDS-neuropathy disability score was used. The acquired data was entered into SPSS Statistics software for analysis of significant associations between these variables. Statistical significance was defined as a P-value below 0.05.

Results

In this study, we investigated 139 patients with a mean age of 62.20±12.03 years, comprising 60.4% males. The mean HbA1c was 7.46±1.09%, and the mean duration of diabetes was 10.78±7.75 years. Most patients (75.5%) had poor glycemic control, with 92.8% having Type-II diabetes. The mean neuropathy disability score was 5.63±2.39, with 80.6% of patients experiencing neuropathy. Nerve conduction velocity slowing was detected in 54.7% of the patients. Notably, significant associations were found between nerve conduction velocity slowing and diabetes duration (p=0.019), and neuropathy disability score (p=0.000).

Conclusion

Our findings indicate that male gender, poor glycemic control, and a longer duration of diabetes are associated with slowing of nerve conduction velocity. Additionally, the severity of neuropathy, as measured by the Neuropathy disability score, further strengthens these associations, highlighting its significance in assessing diabetic neuropathy progression.

Crosstalk between ferroptosis and innate immune in diabetic kidney disease: mechanisms and therapeutic implications

Diabetic kidney disease (DKD) is a prevalent complication of diabetes mellitus (DM), and its incidence is increasing alongside the number of diabetes cases. Effective treatment and long-term management of DKD present significant challenges; thus, a deeper understanding of its pathogenesis is essential to address this issue. Chronic inflammation and abnormal cell death in the kidney closely associate with DKD development. Recently, there has been considerable attention focused on immune cell infiltration into renal tissues and its inflammatory response's role in disease progression. Concurrently, ferroptosis-a novel form of cell death-has emerged as a critical factor in DKD pathogenesis, leading to increased glomerular filtration permeability, proteinuria, tubular injury, interstitial fibrosis, and other pathological processes. The cardiorenal benefits of SGLT2 inhibitors (SGLT2-i) in DKD patients have been demonstrated through numerous large clinical trials. Moreover, further exploratory experiments indicate these drugs may ameliorate serum and urinary markers of inflammation, such as TNF-α, and inhibit ferroptosis in DKD models. Consequently, investigating the interplay between ferroptosis and innate immune and inflammatory responses in DKD is essential for guiding future drug development. This review presents an overview of ferroptosis within the context of DKD, beginning with its core mechanisms and delving into its potential roles in DKD progression. We will also analyze how aberrant innate immune cells, molecules, and signaling pathways contribute to disease progression. Finally, we discuss the interactions between ferroptosis and immune responses, as well as targeted therapeutic agents, based on current evidence. By analyzing the interplay between ferroptosis and innate immunity alongside its inflammatory responses in DKD, we aim to provide insights for clinical management and drug development in this area.

Crumbling Pathogenesis and Biomarkers for Diabetic Peripheral Neuropathy

Background: Diabetic sensorimotor polyneuropathy (DSP) is a common chronic diabetic complication. Traditionally, DSP was once considered irreversible with a typical loss of axon. However, the superimpose of acquired demyelination on axonal loss in DSP patients has been observed, implying that DSP may be preventable or reversible, particularly within a subgroup of patients exhibiting early-stage acquired demyelination, underscoring the critical importance of identifying early prognostic markers. Methods: We systemically review the literature on the roles of biomarkers in predicting DSP and monitoring the progress. The underlying mechanisms of biomarkers were also discussed. Results: The pathogenesis of DSP is multifaceted, with various pathological mechanisms contributing to its development. Key mechanisms include aberrant glucose metabolism and induction of oxidative stress and inflammation. Several pathological processes, such as disrupted glucose metabolism, nerve damage, impaired microcirculation, genetic variants, and microRNA dysregulation, lead to molecular and protein changes that may be detectable in blood and other biological compartments, thus serving as potential biomarkers for DSP progression. However, the utility of a biomarker depends on its predictive accuracy, practicality, and ease of measurement. Conclusions: Most biomarkers for predicting DSP have demonstrated suboptimal predictive value, and many lack established accuracy in forecasting DSP progression. Consequently, the diagnostic utility of any single biomarker remains limited. A comprehensive combination of biomarkers from various categories may hold incredible promise for accurate detection. As artificial intelligence (AI) techniques, especially machine learning, rapidly advance, these technologies may offer significant potential for developing diagnostic platforms to integrate and interpret complex biomarker data for DSP.

Endothelial Markers in Type 2 Diabetic Patients with Acute Decompensated Heart Failure: A Pilot Study

BACKGROUND

Impaired endothelial function has been associated with vascular complications in type 2 diabetes (T2D), but its role in T2D-related heart failure (HF) remains indeterminate. The aim of this study was to assess selected markers of endothelial function in T2D patients with acute decompensated HF.

METHODS

A pilot prospective study on patients with acute decompensated HF requiring in-hospital admission was carried out. The vascular endothelial growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1), and vascular cell adhesion molecule 1 (VCAM-1) were assessed at admission and after decongestion. Subsequently, differences in these markers between T2D and non-diabetic (ND) patients were studied.

RESULTS

In total, 39 patients (21 with T2D and 18 ND patients) were enrolled. Twenty-eight patients presented with preserved ejection fraction (EF), and 11 presented with reduced EF. Looking at the VEGF levels in T2D patients, on admission, a median of 233.0 pg/mL (1.7-598 pg/mL) was found compared to 106.0 pg/mL (1.7-888 pg/mL) in ND individuals; the differences reached statistical significance (p = 0.04). There were no significant differences in VEGF levels after decongestion, and in VCAM-1 (2237 ± 1195 vs. 2699 ± 1093 ng/mL, p = 0.37) and ICAM-1 (596 ± 268 vs. 638 ± 437 ng/mL, p = 0.79) levels between T2D and ND patients upon admission and after decongestion. The value of EF (preserved or reduced) affected the VEGF levels upon admission.

CONCLUSIONS

This study identified significantly higher VEGF levels upon admission due to acute decompensated HF in T2D patients.

The Effect of Autologous Dendritic Cell Immunotherapy on Kidney Function and Endothelial Dysfunction of Patients with Diabetic Kidney Disease (DKD): An Open Label Clinical Trial

This study aimed to evaluate the effects of autologous dendritic cell (DC) immunotherapy on clinical outcomes (glomerular filtration rate/GFR and urine creatinine albumin ratio/UACR) and endothelial dysfunction (ICAM, VCAM, VEGF) in patients with diabetic kidney disease (DKD). Endothelial dysfunction induced by inflammation is one of the key factors in the pathogenesis of DKD. In this one-group pretest-posttest quasi-experimental study, 69 subjects with DKD were administered a single dose of autologous DC immunotherapy ex vivo. UACR was measured at baseline and at weeks 1, 2, 3, and 4, while ICAM, VCAM, VEGF, and GFR were measured at baseline and at week 4 post-immunotherapy. The results showed a significant reduction in median UACR from 250 (IQR 71-668) mg/g at baseline to 164 (IQR 49-576) mg/g at week 4 (p < 0.05). GFR did not show any significant changes after immunotherapy. HbA1c (B = -33.270, p = 0.021) and baseline UACR (B = -0.185, p < 0.001) were identified as significant predictors of UACR change. Although there were no significant changes in ICAM, VCAM, and VEGF, subgroup analysis revealed a decrease in VCAM in macroalbuminuria patients and an increase in those with good glycemic control, suggesting differing endothelial responses. In conclusion, autologous DC immunotherapy effectively reduced UACR in DKD patients, and significant VCAM changes were found in macroalbuminuria and good glycemic control subjects. Further research is needed to understand the mechanisms behind UACR reduction and the long-term impact of this therapy.

Empagliflozin in Acute Myocardial Infarction Reduces No-Reflow and Preserves Cardiac Function by Preventing Endothelial Damage

Empagliflozin treatment before acute myocardial infarction mainly targets the endothelial cell transcriptome. Empagliflozin treatment before and after myocardial infarction decreased no reflow and microvascular injury, leading to reduced infiltration of inflammatory cells, reduced infarct size, and improved cardiac function in mice. In diabetic patients receiving empagliflozin after myocardial infarction, perfused boundary region, flow-mediated dilation, and global longitudinal strain were improved.

Soluble P-Selectin as an Indicator of Cutaneous Microangiopathy in Uncomplicated Young Patients with Type 1 Diabetes

This study aimed to analyze the relationship between cutaneous microcirculation reactivity, retinal circulation, macrocirculation function, and specific adhesion molecules in young patients with uncomplicated type 1 diabetes. Fifty-five patients with type 1 diabetes mellitus (T1DM), aged 8 to 18 years, were divided into subgroups based on skin microcirculation reactivity. The cutaneous microcirculatory vessels were considered reactive if post-test PORH coverage increased compared to pre-test coverage. Optical coherence tomography (OCT) was conducted to detect early retinopathic changes. Macrocirculation was described using pulsatility indices (PIs) determined for common carotid (CCA) and peripheral arteries of the upper and lower limbs. The ankle-brachial index was also assessed. There were no significant differences in retinal circulation and macrocirculation between the studied subgroups. However, there were significant differences between the various subgroups concerning the age at onset of diabetes and the sP-selectin levels but not ICAM-1 and sVCAM-1. The sP-selectin differences remained true after adjusting for age at onset. The sP-selectin level was significantly higher in the subgroup of patients with non-reactive cutaneous microcirculation. The results of our study indicate that sP-selectin may be considered as an immunological marker for cutaneous abnormalities, which serve as an early indicator of endothelial dysfunction in young patients with type 1 diabetes in the absence of classical complication.

NF-kappa B signaling pathway is associated with metformin resistance in type 2 diabetes patients

Introduction

Metformin is an essential medicine that is most widely prescribed frontline for the treatment of Type 2 diabetes (T2D). Metformin upgraded glycemic control in T2D patients without hypoglycemic effects in patients. This assessment aims to understand molecular mechanism mechanisms in non-responder patients to metformin.

Methods

Gene expression profiles of responder and non-responder T2D patients to metformin are extracted from Gene Expression Omnibus (GEO) and are evaluated by the GEO2R program to find the significant differentially expressed genes (DEGs). The significant DEGs have been studied via action map gene ontology analyses.

Results

Results indicate that 563 significant DEGs discriminate non-responders from responder groups. "NF-kappa B signaling pathway" and 11 DEGs including BIRC3, CCL4L2, CXCL2, ICAM1, LYN, MYD88, RELA, SYK, TLR4, TNFAIP3, and TRIM25 were pointed out as core of drug resistance.

Conclusion

It can be concluded that there are differences between gene expression analysis, the response of diabetic patients to metformin. Results indicate that dysregulation of the "NF-kappa B signaling pathway" and TNFAIP3, BIRC3, RELA, MYD88, TLR4, and ICAM1 is associated with drug resistance in T2D patients.

Elevated Inflammation and Adhesion Molecule hsCRP, GDF-15 and VCAM-1 in Angina Patients with Non-obstructive Coronary Artery Disease

Background

Non-obstructive coronary artery disease (NOCAD) is a condition in stable patients that experience angina despite not having significant coronary obstructive lesion. Knowledge on the role of certain biomarkers in patients with NOCAD is still limited. This study aimed to evaluate the roles of inflammation and adhesion molecules in the development of NOCAD. The correlations between the peripheral and coronary levels of the inflammatory biomarkers and adhesion molecules were also investigated.

Methods

In this cross-sectional study, symptomatic angina patients scheduled for coronary angiograms were recruited and separated into obstructive coronary artery disease (OCAD) and NOCAD groups based on those angiograms. Peripheral and coronary blood samples were taken to measure inflammation biomarkers [high sensitivity C-reactive protein (hsCRP) and growth differentiation factor 15 (GDF-15)], and adhesion molecules [vascular cell adhesion molecule-1 (VCAM-1)]. Subjects without angina symptoms were recruited for the control group.

Results

The hsCRP, GDF-15, and VCAM-1 levels were higher in the OCAD and NOCAD groups than in the control group. VCAM-1 levels successfully predicted the incidence of NOCAD [p = 0.010, area under the curve (AUC) = 0.716]. All biomarkers' levels in the peripheral and coronary blood were correlated in OCAD and NOCAD patients (p < 0.001).

Conclusion

Elevated levels of the hsCRP, GDF-15, and VCAM-1 were found with NOCAD, despite the absent of significant coronary obstruction. VCAM-1 successfully predicted NOCAD and may thus serve as an early NOCAD biomarker. Significant correlations of hsCRP, GDF-15, and VCAM-1 level in peripheral and coronary blood indicate that the peripheral levels of these biomarkers reflect the levels and changes that occur at the coronary level.

Mechanisms of Insulin Signaling as a Potential Therapeutic Method in Intestinal Diseases

Gastrointestinal diseases are becoming a growing public health problem. One of them is inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD). The incidence of IBD is increasing in developing countries and declining in developed countries, affecting people of all ages. Researchers have been exploring new treatment options including insulin signaling pathways in the inflammation of the gastrointestinal tract. It seems that a better understanding of the mechanism of IGF-1, GLP-1 and TL1A on the gut microbiota and inflammation may provide new advances in future therapeutic strategies for patients with IBD, but also other intestinal diseases. This review aims to synthesize insights into the effects of GLP, IGF and anti-TL1A on inflammation and the gut microbiota, which may enable their future use in therapy for people with intestinal diseases.

Association of Urinary Epidermal Growth Factor, Fatty Acid-Binding Protein 3, and Vascular Cell Adhesion Molecule 1 Levels with the Progression of Early Diabetic Kidney Disease

INTRODUCTION

Diabetic kidney disease (DKD) is a common cause of chronic kidney disease with around 25-40% of patients with diabetes being affected. The course of DKD is variable, and estimated glomerular filtration rate (eGFR) and albuminuria, the currently used clinical markers, are not able to accurately predict the individual disease trajectory, in particular in early stages of the disease. The aim of this study was to assess the association of urine levels of selected protein biomarkers with the progression of DKD at an early stage of disease.

METHODS

We measured 22 protein biomarkers using the Mesoscale Discovery platform in 461 urine samples of the PROVALID cohort, an observational study of patients with type 2 diabetes mellitus followed at the primary health care level for a minimum of 4 years. Odds ratios (ORs) were estimated for the effect of marker values above median on fast progression using unadjusted and adjusted logistic regression models. RNA expression at the single-cell level in kidney biopsy samples obtained from a cohort of young persons with type 2 diabetes mellitus was in addition determined for markers showing significant associations with disease progression.

RESULTS

Increased urinary levels of epidermal growth factor (EGF) were linked to lower odds of fast progression (defined as annual eGFR decline greater than 2.58 mL/min per 1.73 m2) with an OR of 0.60 (95% CI: 0.46, 0.78). The association with outcome was even stronger when adjusting for a set of 14 baseline clinical parameters including age, biological sex, eGFR, body mass index, albuminuria, and HbA1c. Elevated urinary levels of fatty acid-binding protein 3 (FABP3) and vascular cell adhesion molecule 1 (VCAM1) were each significantly associated with fast progression with an OR of 1.44 (95% CI: 1.11, 1.87) and an OR of 1.41 (95% CI: 1.08, 1.83), respectively. Enriched expression of EGF and FABP3 was observed in distal convoluted tubular cells and VCAM1 in parietal epithelial cells at single-cell level from biopsies of patients with early DKD.

CONCLUSION

In summary, we show that lower urinary levels of EGF and higher urinary levels of FABP3 and VCAM1 are significantly associated with DKD progression in early-stage disease.

Comparison of clinical characteristics, microvascular complications and inflammatory markers in type 2 diabetic patients under insulin versus metformin treatment: A cross-sectional study at Karbala Diabetic Center, Iraq

Type 2 diabetes mellitus (T2DM) is a major global health issue associated with chronic inflammation, which contributes to both disease progression and its complications, including cardiovascular and microvascular disorders. Key inflammatory markers such as tumor necrosis factor-alpha, interleukin-6 (IL-6), E-selectin, and P-selectin are elevated in T2DM patients and are implicated in the development of these complications. Understanding how treatments such as insulin and metformin affect these markers is crucial for improving therapeutic strategies in T2DM. This study investigated the effects of insulin and metformin on these inflammatory markers in T2DM patients. This was a cross-sectional study involving patients with diabetes on insulin (group A), metformin only (group B), and healthy controls (group C). Participants were enrolled from the Diabetic Center in Karbala, Iraq and underwent clinical assessments including ophthalmologic examinations. Fasting blood glucose, HbA1c and lipids levels were assessed. The levels of inflammatory markers (IL-6 and TNF-α), and adhesion molecules (sE-selectin and sP-selectin) were measured using Enzyme-Linked Immunosorbent Assay (ELISA). The study included 522 patients with diabetes: 356 receiving insulin (group A), 70 receiving metformin (group B) and 96 healthy controls (group C). T2DM patients treated with insulin exhibited significantly more microvascular complications than those treated with metformin. Higher rates of retinopathy (64.3% vs 11.4%) and neuropathy (69.9% vs 11.4%) were observed in the insulin group, whereas the incidence of nephropathy did not differ significantly (14.6% vs 11.4%). Inflammatory markers were lower in the insulin group: TNF-α levels were 3-fold lower and IL-6 levels were 8-fold lower. Conversely, sE-selectin levels were 1.5-fold higher in the insulin group, and sP-selectin levels were 1.4-fold higher in the metformin group. This study highlights distinct differences in inflammatory markers and systemic complications between T2DM patients treated with insulin and those treated with metformin alone. Further research is needed to explore the mechanisms underlying these observations and optimize treatment strategies for T2DM patients.

Protective Role of High-Density Lipoprotein in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic, progressive demyelinating disease with a most likely autoimmune background and a neurodegenerative component. Besides the demyelinating process caused by autoreactive antibodies, an increased permeability in the blood-brain barrier (BBB) also plays a key role. Recently, there has been growing interest in assessing lipid profile alterations in patients with MS. As a result of myelin destruction, there is an increase in the level of cholesterol released from cells, which in turn causes disruptions in lipid metabolism homeostasis both in the central nervous system (CNS) and peripheral tissues. Currently, there is a growing body of evidence suggesting a protective role of HDL in MS through its effect on the BBB by decreasing its permeability. This follows from the impact of HDL on the endothelium and its anti-inflammatory effect, mostly by interacting with adhesion molecules like vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), and E-selectin. HDL, through its action via sphingosine-1-phosphate, exerts an inhibitory effect on leukocyte migration, and its antioxidant properties contribute to the improvement of the BBB function. In this review, we want to summarize these studies and focus on HDL as a mediator of the anti-inflammatory response in MS.

Nanocarriers for targeted drug delivery in the vascular system: focus on endothelium

Endothelial cells (ECs) are pivotal in maintaining vascular health, regulating hemodynamics, and modulating inflammatory responses. Nanocarriers hold transformative potential for precise drug delivery within the vascular system, particularly targeting ECs for therapeutic purposes. However, the complex interactions between vascular ECs and nanocarriers present significant challenges for the development and clinical translation of nanotherapeutics. This review assesses recent advancements and key strategies in employing nanocarriers for drug delivery to vascular ECs. It suggested that through precise physicochemical design and surface modifications, nanocarriers can enhance targeting specificity and improve drug internalization efficiency in ECs. Additionally, we elaborated on the applications of nanocarriers specifically designed for targeting ECs in the treatment of cardiovascular diseases, cancer metastasis, and inflammatory disorders. Despite these advancements, safety concerns, the complexity of in vivo processes, and the challenge of achieving subcellular drug delivery remain significant obstacles to the effective targeting of ECs with nanocarriers. A comprehensive understanding of endothelial cell biology and its interaction with nanocarriers is crucial for realizing the full potential of targeted drug delivery systems.

Low brain-derived neurotrophic factor and high vascular cell adhesion molecule-1 levels are associated with chronic kidney disease in patients with type 2 diabetes mellitus

Background

Patients with type 2 diabetes mellitus (DM) have a high prevalence of chronic kidney disease (CKD). Energy imbalance and inflammation may be involved in the pathogenesis of CKD. We examined the effects of brain-derived neurotrophic factor (BDNF) and vascular cell adhesion molecule-1 (VCAM-1) on CKD in patients with type 2 DM.

Methods

Patients with type 2 DM were enrolled for this cross-sectional study. Fasting serum was prepared to measure the BDNF and VCAM-1 levels. An estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 was used as the criterion for identifying patients with CKD.

Results

Of the 548 enrolled participants, 156 had CKD. Patients with CKD exhibited significantly lower BDNF (median of 21.4 ng/mL, interquartile range [IQR]: 17.0-27.0 ng/mL vs. median of 25.9 ng/mL, IQR: 21.0-30.4 ng/mL, P <0.001) and higher VCAM-1 (median of 917 ng/mL, IQR: 761-1172 ng/mL vs. median of 669 ng/mL, IQR: 552-857 ng/mL, P <0.001) levels than those without CKD. Serum BDNF levels were inversely correlated with VCAM-1 levels (Spearman's rank correlation coefficient = -0.210, P <0.001). The patients were divided into four subgroups based on median BDNF and VCAM-1 levels (24.88 ng/mL and 750 ng/mL, respectively). Notably, patients in the high VCAM-1 and low BDNF group had the highest prevalence (50%) of CKD. Multivariate logistic regression revealed a significantly higher odds ratio (OR) of CKD in the high VCAM-1 and low BDNF group (OR = 3.885, 95% CI: 1.766-8.547, P <0.001), followed by that in the high VCAM-1 and high BDNF group (OR = 3.099, 95% CI: 1.373-6.992, P =0.006) compared with that in the low VCAM-1 and high BDNF group. However, the risk of CKD in the low VCAM-1 and low BDNF group was not significantly different from that in the low VCAM-1 and high BDNF group (P =0.266).

Conclusion

CKD in patients with type 2 DM is associated with low serum BDNF and high VCAM-1 levels. BDNF and VCAM-1 have a synergistic effect on CKD. Thus, BDNF and VCAM-1 can be potential biomarkers for CKD risk stratification in patients with type 2 DM.

The mineralocorticoid receptor in diabetic kidney disease

Diabetes mellitus is one of the leading causes of chronic kidney disease and its progression to end-stage kidney disease (ESKD). Diabetic kidney disease (DKD) is characterized by glomerular hypertrophy, hyperfiltration, inflammation, and the onset of albuminuria, together with a progressive reduction in glomerular filtration rate. This progression is further accompanied by tubulointerstitial inflammation and fibrosis. Factors such as genetic predisposition, epigenetic modifications, metabolic derangements, hemodynamic alterations, inflammation, and inappropriate renin-angiotensin-aldosterone system (RAAS) activity contribute to the onset and progression of DKD. In this context, decades of work have focused on glycemic and blood pressure reduction strategies, especially targeting the RAAS to slow disease progression. Although much of the work has focused on targeting angiotensin II, emerging data support that the mineralocorticoid receptor (MR) is integral in the development and progression of DKD. Molecular mechanisms linked to the underlying pathophysiological changes derived from MR activation include vascular endothelial and epithelial cell responses to oxidative stress and inflammation. These responses lead to alterations in the microcirculatory environment, the abnormal release of extracellular vesicles, gut dysbiosis, epithelial-mesenchymal transition, and kidney fibrosis. Herein, we present recent experimental and clinical evidence on the MR in DKD onset and progress along with new MR-based strategies for the treatment and prevention of DKD.

Causal Effects of Oxidative Stress on Diabetes Mellitus and Microvascular Complications: Insights Integrating Genome-Wide Mendelian Randomization, DNA Methylation, and Proteome

BACKGROUND

Oxidative stress (OS) is involved in the development of diabetes, but the genetic mechanisms are not completely understood. We integrated multi-omics data in order to explore the genetic relations between OS-related genes, diabetes mellitus, and microvascular complications using Mendelian randomization and colocalization analysis.

METHODS

Summary-level data related to OS were acquired from respective studies of methylation, expression, and protein abundance quantitative trait loci. Genetic associations concerning diabetes, diabetic nephropathy (DN), and diabetic retinopathy (DR) were derived from the FinnGen study. Summary-data-based Mendelian randomization (SMR) analysis was conducted to evaluate the correlations between molecular features concerned with OS-related genes and diabetes mellitus, along with its microvascular complications. Additionally, we performed colocalization analysis to determine if the detected signal pairs shared a causal genetic variant.

RESULTS

At the genetic level, we identified ten potential causal associations of oxidative stress genes with diabetes, along with microvascular complications, through SMR and colocalization analysis. After integrating the DNA methylation quantitative trait loci (mQTL) and expression QTL (eQTL) data, our analyses revealed a correlation between the methylation site cg26343298 and reduced expression of TP53INP1, supporting the protective role of cg26343298 methylation on type 2 diabetes (T2D) and diabetic nephropathy. Similarly, an inverse association was observed between gene methylation and expression in CHEK1 (cg07110182), confirming the beneficial effect of modification of CHEK1 by cg07110182 in diabetic retinopathy. In addition, upregulation of SUOX expression by cg22580629 was linked to a reduced risk of diabetic retinopathy. At circulating protein levels, genetically predicted a higher level of ICAM1 (OR 1.05, 95%CI 1.03-1.08) was positively connected with the risk of diabetic retinopathy.

CONCLUSIONS

This SMR study elucidated that the TP53INP1 gene was putatively associated with T2D and DN risk, while the SUOX and CHEK1 genes were associated with DR risk through oxidative stress mechanisms. Additionally, our study showed a positive correlation between the ICAM-1 protein and DR. These findings may enhance our understanding of their pathogenesis and suggest new therapeutic targets for clinical practice.

A neural network model for predicting the effectiveness of treatment in patients with neovascular glaucoma associated with diabetes mellitus

Introduction

The study hypothesizes that neural networks can be an effective tool for predicting treatment outcomes in patients with diabetic neovascular glaucoma (NVG), considering not only baseline intraocular pressure (IOP) values but also inflammation and intraocular microcirculation indicators.

Objective

To investigate the diagnostic significance of inflammation and intraocular blood circulation indicators in a neural network model predicting the effectiveness of transscleral cyclophotocoagulation (TSC CPC) treatment in patients with NVG of diabetic origin.

Methods

This retrospective cohort study included 127 patients (127 eyes; aged Me 65.0 years) with painful diabetic NVG and 20 healthy individuals (aged Me 61.5 years) as an immunological control. All patients underwent TSC CPC with a diode laser. Treatment success was defined as achieving an IOP level of ≤ 21 mmHg and maintaining or improving best-corrected visual acuity (BCVA) after 12 months of observation. Preoperative systemic immune-inflammation index (SII = platelets × [neutrophils/lymphocytes]) and systemic inflammation response index (SIRI = neutrophils × [monocytes/lymphocytes]) were calculated. We assessed the values of volumetric pulse blood filling, determined by the rheographic coefficient (RQ, 0/00), using the rheoophthalmography (ROG) method. Multiple regression analysis was used to conclude the significance of treatment efficacy based on initial clinical and laboratory indicators, followed by constructing a prediction model in the neural network.

Results

The development of the neural network model identified the most significant "input" parameters: SIRI (100%), RQ (85.7%), and SII (80.7%), which significantly influenced treatment success. The sensitivity of the neural network model was 100%, specificity was 30%, and the percentage of correctly predicted events during testing on the control group was 92.9%.

Conclusions

Neural network-based prediction of transscleral cyclophotocoagulation effectiveness for patients with diabetic neovascular glaucoma allows for a sufficiently accurate forecast of treatment success with a probability of 92.9%. We believe the in-time correction of systemic inflammation and intraocular blood circulation can significantly reduce intraocular pressure, preserve visual acuity, and improve the quality of life in patients with diabetic NVG after TSC CPC. Further research is required to support these findings.

Effect of GLP-1RA Treatment on Adhesion Molecules and Monocyte Chemoattractant Protein-1 in Diabetic Patients with Atherosclerosis

Cardiovascular disease (CVD) remains a prominent cause of global mortality, primarily driven by atherosclerosis. Diabetes mellitus, as a modifiable risk factor, significantly contributes to atherogenesis. Monocyte recruitment to the intima is a critical step in atherosclerotic plaque formation, involving chemokines and adhesion molecules such as selectins, ICAM-1, and MCP-1. Glucagon-like peptide 1 receptor agonists (GLP-1RAs) are a promising group of drugs for reducing cardiovascular risk in diabetic patients, prompting investigation into their mechanisms of action. This interventional study enrolled 50 diabetes patients with atherosclerotic plaque, administering GLP-1RA for 180 days. Serum concentrations of MCP-1, ICAM-1, and L-selectin were measured before and after treatment. Anthropometric and biochemical parameters were also assessed. GLP-1RA treatment resulted in significant improvements in anthropometric parameters, glycemic control, blood pressure, and biochemical markers of liver steatosis. Biomarker laboratory analysis revealed higher baseline levels of MCP-1, ICAM-1, and L-selectin in diabetic patients with atherosclerotic plaque compared to healthy controls. Following treatment, MCP-1 and L-selectin levels decreased significantly (p < 0.001), while ICAM-1 levels increased (p < 0.001). GLP-1RA treatment in diabetic patients with atherosclerotic plaque leads to favorable changes in serum molecule levels associated with monocyte recruitment to the endothelium. The observed reduction in MCP-1 and L-selectin suggests a potential mechanism underlying GLP-1RA-mediated cardiovascular risk reduction. Further research is warranted to elucidate the precise mechanisms and clinical implications of these findings in diabetic patients with atherosclerosis.

Diabetic Retinopathy: New Treatment Approaches Targeting Redox and Immune Mechanisms

Diabetic retinopathy (DR) represents a severe complication of diabetes mellitus, characterized by irreversible visual impairment resulting from microvascular abnormalities. Since the global prevalence of diabetes continues to escalate, DR has emerged as a prominent area of research interest. The development and progression of DR encompass a complex interplay of pathological and physiological mechanisms, such as high glucose-induced oxidative stress, immune responses, vascular endothelial dysfunction, as well as damage to retinal neurons. Recent years have unveiled the involvement of genomic and epigenetic factors in the formation of DR mechanisms. At present, extensive research explores the potential of biomarkers such as cytokines, molecular and cell therapies, antioxidant interventions, and gene therapy for DR treatment. Notably, certain drugs, such as anti-VEGF agents, antioxidants, inhibitors of inflammatory responses, and protein kinase C (PKC)-β inhibitors, have demonstrated promising outcomes in clinical trials. Within this context, this review article aims to introduce the recent molecular research on DR and highlight the current progress in the field, with a particular focus on the emerging and experimental treatment strategies targeting the immune and redox signaling pathways.

Endothelial dysfunction in vascular complications of diabetes: a comprehensive review of mechanisms and implications

Diabetic vascular complications are prevalent and severe among diabetic patients, profoundly affecting both their quality of life and long-term prospects. These complications can be classified into macrovascular and microvascular complications. Under the impact of risk factors such as elevated blood glucose, blood pressure, and cholesterol lipids, the vascular endothelium undergoes endothelial dysfunction, characterized by increased inflammation and oxidative stress, decreased NO biosynthesis, endothelial-mesenchymal transition, senescence, and even cell death. These processes will ultimately lead to macrovascular and microvascular diseases, with macrovascular diseases mainly characterized by atherosclerosis (AS) and microvascular diseases mainly characterized by thickening of the basement membrane. It further indicates a primary contributor to the elevated morbidity and mortality observed in individuals with diabetes. In this review, we will delve into the intricate mechanisms that drive endothelial dysfunction during diabetes progression and its associated vascular complications. Furthermore, we will outline various pharmacotherapies targeting diabetic endothelial dysfunction in the hope of accelerating effective therapeutic drug discovery for early control of diabetes and its vascular complications.

Construction of a diagnostic model based on random forest and artificial neural network for peri-implantitis

OBJECTIVES

This study aimed to reveal critical genes regulating peri-implantitis during its development and construct a diagnostic model by using random forest (RF) and artificial neural network (ANN).

METHODS

GSE-33774, GSE106090, and GSE57631 datasets were obtained from the GEO database. The GSE33774 and GSE106090 datasets were analyzed for differential expression and functional enrichment. The protein-protein interaction networks (PPI) and RF screened vital genes. A diagnostic model for peri-implantitis was established using ANN and validated on the GSE33774 and GSE57631 datasets. A transcription factor-gene interaction network and a transcription factor-micro-RNA (miRNA) regulatory network were also established.

RESULTS

A total of 124 differentially expressed genes (DEGs) involved in the regulation of peri-implantitis were screened. Enrichment analysis showed that DEGs were mainly associated with immune receptor activity and cytokine receptor activity and were mainly involved in processes such as leukocyte and neutrophil migration. The PPI and RF screened six essential genes, namely, CD38, CYBB, FCGR2A, SELL, TLR4, and CXCL8. The receiver operating characteristic curve (ROC) indicated that the ANN model had an excellent diagnostic performance. FOXC1, GATA2, and NF-κB1 may be essential transcription factors in peri-implantitis, and hsa-miR-204 may be a key miRNA.

CONCLUSIONS

The diagnostic model of peri-implantitis constructed by RF and ANN has high confidence, and CD38, CYBB, FCGR2A, SELL, TLR4, and CXCL8 are potential diagnostic markers. FOXC1, GATA2, and NF-κB1 may be essential transcription factors in peri-implantitis, and hsa-miR-204 plays a vital role as a critical miRNA.

The effect of the intercellular adhesion molecule-1 and glycated haemoglobin on the management of diabetic neovascular glaucoma

Introduction: The study hypothesizes that some patients with diabetic neovascular glaucoma (NVG) do not fully respond to transscleral (TSC) cyclophotocoagulation (CPC) due to significant inflammation and insufficient glucose control. Objective: The study aimed to determine the effect of baseline blood levels of intercellular adhesion molecule-1 (ICAM-1) and glycated haemoglobin (HbA1c) on the management of patients with diabetic NVG by TSC CPC. Methods: This open prospective study included 70 diabetic patients (75 eyes; aged Ме 63.0 years) with painful NVG and 20 healthy individuals (aged Ме 61.5 years) as an immunological control. All patients underwent TSC СPC with a diode laser. Baseline HbA1c levels and ICAM-1 expression in blood samples were determined. Follow-up was 12 months. Results: One month after TSC CPC, IOP decreased by 28% compared to baseline. The effectiveness of laser treatment after 12 months of follow-up was 63% with IOP decrease by 46%. In patients with NVG, the initial level of ICAM-1 was 2.5 times higher than in the control group. Patients who did not fully respond to the first TSC CPC (30 eyes) and required additional laser procedure, had high initial HbA1c (9.5%) and high expression values of the ICAM-1 (609.0 cells/μL). Conclusions: Repeated procedures of TSC CPC at high IOP in diabetic patients with NVG are associated with high initial values of expression of ICAM-1 in peripheral blood and high HbA1c. The strategy of management of patients with diabetic NVG should be aimed at intensive glucose control and local anti-inflammatory treatment. Abbreviations: PDR = proliferative diabetic retinopathy, DR = diabetic retinopathy, NVG = neovascular glaucoma, TSC CPC = transscleral cyclophotocoagulation, ICAM-1 = intercellular adhesion molecule-1, HbA1c = glycated haemoglobin, IOP = intraocular pressure.

The therapeutic effects of marine sulfated polysaccharides on diabetic nephropathy

Marine sulfated polysaccharide (MSP) is a natural high molecular polysaccharide containing sulfate groups, which widely exists in various marine organisms. The sources determine structural variabilities of MSPs which have high security and wide biological activities, such as anticoagulation, antitumor, antivirus, immune regulation, regulation of glucose and lipid metabolism, antioxidant, etc. Due to the structural similarities between MSP and endogenous heparan sulfate, a majority of studies have shown that MSP can be used to treat diabetic nephropathy (DN) in vivo and in vitro. In this paper, we reviewed the anti-DN activities, the dominant mechanisms and structure-activity relationship of MSPs in order to provide the overall scene of MSPs as a modality of treating DN.

Mechanisms of endothelial activation, hypercoagulation and thrombosis in COVID-19: a link with diabetes mellitus

Early since the onset of the COVID-19 pandemic, the medical and scientific community were aware of extra respiratory actions of SARS-CoV-2 infection. Endothelitis, hypercoagulation, and hypofibrinolysis were identified in COVID-19 patients as subsequent responses of endothelial dysfunction. Activation of the endothelial barrier may increase the severity of the disease and contribute to long-COVID syndrome and post-COVID sequelae. Besides, it may cause alterations in primary, secondary, and tertiary hemostasis. Importantly, these responses have been highly decisive in the evolution of infected patients also diagnosed with diabetes mellitus (DM), who showed previous endothelial dysfunction. In this review, we provide an overview of the potential triggers of endothelial activation related to COVID-19 and COVID-19 under diabetic milieu. Several mechanisms are induced by both the viral particle itself and by the subsequent immune-defensive response (i.e., NF-κB/NLRP3 inflammasome pathway, vasoactive peptides, cytokine storm, NETosis, activation of the complement system). Alterations in coagulation mediators such as factor VIII, fibrin, tissue factor, the von Willebrand factor: ADAMST-13 ratio, and the kallikrein-kinin or plasminogen-plasmin systems have been reported. Moreover, an imbalance of thrombotic and thrombolytic (tPA, PAI-I, fibrinogen) factors favors hypercoagulation and hypofibrinolysis. In the context of DM, these mechanisms can be exacerbated leading to higher loss of hemostasis. However, a series of therapeutic strategies targeting the activated endothelium such as specific antibodies or inhibitors against thrombin, key cytokines, factor X, complement system, the kallikrein-kinin system or NETosis, might represent new opportunities to address this hypercoagulable state present in COVID-19 and DM. Antidiabetics may also ameliorate endothelial dysfunction, inflammation, and platelet aggregation. By improving the microvascular pathology in COVID-19 and post-COVID subjects, the associated comorbidities and the risk of mortality could be reduced.

Trimethylamine N-oxide aggravates vascular permeability and endothelial cell dysfunction under diabetic condition: in vitro and in vivo study

AIM

To provide the direct evidence for the crucial role of trimethylamine N-oxide (TMAO) in vascular permeability and endothelial cell dysfunction under diabetic condition.

METHODS

The role of TMAO on the in vitro biological effect of human retinal microvascular endothelial cells (HRMEC) under high glucose conditions was tested by a cell counting kit, wound healing, a transwell and a tube formation assay. The inflammation-related gene expression affected by TMAO was tested by real-time polymerase chain reaction (RT-PCR). The expression of the cell junction was measured by Western blotting (WB) and immunofluorescence staining. In addition, two groups of rat models, diabetic and non-diabetic, were fed with normal or 0.1% TMAO for 16wk, and their plasma levels of TMAO, vascular endothelial growth factor (VEGF), interleukin (IL)-6 and tumor necrosis factor (TNF)-α were tested. The vascular permeability of rat retinas was measured using FITC-Dextran, and the expression of zonula occludens (ZO)-1 and claudin-5 in rat retinas was detected by WB or immunofluorescence staining.

RESULTS

TMAO administration significantly increased the cell proliferation, migration, and tube formation of primary HRMEC either in normal or high-glucose conditions. RT-PCR showed elevated inflammation-related gene expression of HRMEC under TMAO stimulation, while WB or immunofluorescence staining indicated decreased cell junction ZO-1 and occludin expression after high-glucose and TMAO treatment. Diabetic rats showed higher plasma levels of TMAO as well as retinal vascular leakage, which were even higher in TMAO-feeding diabetic rats. Furthermore, TMAO administration increased the rat plasma levels of VEGF, IL-6 and TNF-α while decreasing the retinal expression levels of ZO-1 and claudin-5.

CONCLUSION

TMAO enhances the proliferation, migration, and tube formation of HRMEC, as well as destroys their vascular integrity and tight connection. It also regulates the expression of VEGF, IL-6, and TNF-α.