Endothelial dysfunction due to selective insulin resistance in vascular endothelium: insights from mechanistic modeling

Impact of a 12-week personalized dietary intervention on vascular function and cardiovascular risk factors

AIMS

Individuals with liver insulin-resistant (LIR) or muscle insulin-resistant (MIR) phenotypes may respond differently to dietary interventions. Given the interaction between insulin resistance and cardiovascular risk, this sub-analysis of the PERSON study examined whether a personalized diet according to MIR or LIR phenotypes improves vascular function and cardiovascular disease risk factors.

MATERIALS AND METHODS

We randomized 119 participants to a 12-week low-fat, high-protein, high-fibre diet (LFHP; may be optimal for LIR) or Mediterranean diet (high in monounsaturated fat, HMUFA; may be optimal for MIR). Randomization linked the insulin-resistant (IR) phenotype to the proposed optimal diet, leading to PhenoDiet A (MIR-HMUFA and LIR-LFHP) and PhenoDiet B (MIR-LFHP and LIR-HMUFA). Before and after the intervention, vascular function (carotid artery reactivity) and cardiovascular risk factors (blood pressure, total cholesterol, HDL-cholesterol and Framingham risk score) were examined. A 7-point oral glucose tolerance test was performed to determine insulin resistance (Matsuda index and HOMA-IR) and disposition index.

RESULTS

Following drop-out (n = 18), 101 participants finished the intervention (54 women, 61 ± 7 years, 27.6 [26.4;30.0] kg/m2), with n = 80 available for the primary outcome of vascular function. Overall, the dietary interventions significantly decreased blood pressure, total cholesterol, HDL-cholesterol and the Framingham risk score (all p < 0.05), while vascular function was not affected (p = 0.485). Insulin resistance (p ≤ 0.001), but not disposition index (p = 0.362), was significantly improved after intervention. The Matsuda index (p = 0.078) tended to increase more and total cholesterol (p = 0.052) tended to decrease more in PhenoDiet group B than A, but other changes in outcome parameters were not significantly different between PhenoDiet groups. The LFHP diet resulted in more pronounced improvements in cholesterol, diastolic blood pressure (DBP) and insulin resistance compared with the HMUFA diet (all p < 0.05).

CONCLUSION

A 12-week diet improves metabolic and cardiovascular outcomes, but not vascular function in insulin-resistant adults with overweight or obesity. Whilst the LFHP diet resulted in greater improvements in cardiometabolic risk markers than the HMUFA diet, we found no significant differences between the PhenoDiet groups.

Exploration of metformin-based drug combination for mitigating diabetes-associated atherosclerotic diseases

Diabetes mellitus is a substantial global health threat due to its high prevalence and its serious complications. The hyperglycemic state causes damage to vascular endothelial cells and disturbance of lipid metabolism, thus contributing to the development of vascular disorders, especially atherosclerotic diseases. Aggressive glycemic control combined with vascular intervention is critical to the prevention and treatment of diabetes-associated atherosclerosis. It is suggested that metformin should be combined with hypoglycemic agents with proven vascular benefits for treating type 2 diabetes (T2DM) complicated with atherosclerotic diseases. Clinical studies indicates that the preferred combination is metformin with either glucagon-like peptide-1 receptor agonist or sodium/glucose cotransporter-2 inhibitor, which could offer additional vascular benefits and reduce the risk of atherosclerotic complications. Likewise, combination therapy with metformin and hypolipidemic agents has also shown additive effects on glucose control and lipid-lowering in patients with both diabetes and dyslipidemia, whereas extensive clinical trials using atherosclerotic-associated outcomes are required to support the vascular benefits. Moreover, co-administration of metformin with systemic antioxidant or anti-inflammatory therapy may also provide additional vascular benefits as indicated by several animal studies. For instance, a recent study found that additional supplementation of cholecalciferol and taurine enhanced metformin efficacy in controlling diabetes while reducing the risk of associated atherosclerotic complications. However, these potential benefits remain need validation by the evidence from clinical studies. Despite the limitations, such as heterogeneity across different patient populations, and deficiency in long-term outcomes, such efforts can contribute to finding optimal drug combinations to improve the management of T2DM and reduce its atherosclerotic complications.

Insulin resistance and periodontitis: Mediation by blood pressure

AIM

This study investigated the association between the triglyceride-glucose (TyG) index, a surrogate marker of insulin resistance, and moderate/severe periodontitis and the role of blood pressure as a mediator in this association. A second aim was to assess the role of cardiometabolic conditions such as obesity, hypertension, and dyslipidemia as potential effect modifiers.

METHODS

Data from 5733 US adults aged 30-64 years and with complete periodontal examination were analyzed (NHANES 2011-2014). Participants were classified as having moderate/severe periodontitis or mild/no periodontitis according to the CDC/AAP criteria as the outcome. The exposure was the TyG index, while both systolic (SBP), and diastolic (DBP) blood pressure were tested as mediators using parametric g-formula. Analyses were adjusted for relevant confounders, namely, age, sex, ethnicity, poverty-income ratio, and smoking, using inverse probability treatment weighting. Obesity status (based on a body mass index ≥30 kg/m2), self-report of hypertension and dyslipidemia (calculated based on the thresholds provided by National Cholesterol Education Program-Adult Treatment Panel-III) were tested as effect modifiers.

RESULTS

The findings showed the TyG index to be associated with increased odds of moderate/severe periodontitis [odds ratio (OR), 95% confidence interval (CI) = 1.17 (1.11-1.23)], with 50% of the total effect mediated by SBP. Stratified analysis showed a stronger association in individuals with obesity, hypertension, and dyslipidemia compared to those without these conditions. However, in those taking anti-hypertensive medications, the association was partially mitigated. Sensitivity analysis using imputed data showed consistent results.

CONCLUSION

The TyG index was associated with increased odds of moderate/severe periodontitis, especially in individuals with obesity, hypertension, and dyslipidemia. SBP levels partially mediated this association.

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.

Unveiling the Negative Synergistic Effect of Wall Shear Stress and Insulin on Endothelial NO Dynamics by Mathematical Modeling

Diabetic vascular complications (DVCs) are diabetes-induced vascular dysfunction and pathologies, leading to the major causes of morbidity and mortality in millions of diabetic patients worldwide. DVCs are provoked by endothelial dysfunction which is closely coordinated with two important hallmarks: one is the insufficient insulin secretion or insulin resistance, and another is the decrease in intracellular nitric oxide (NO) influenced by dynamic wall shear stress (WSS). Although the intracellular NO dynamics in endothelial cells (ECs) is crucial for endothelial function, the regulation of NO production by dynamic WSS and insulin is still poorly understood. In this study, we have proposed a mathematical model of intracellular NO production in ECs under the stimulation of dynamic WSS combined with insulin. The model integrates simultaneously the biochemical signaling pathways of insulin and the mechanotransduction pathways induced by dynamic WSS. The accuracy and reliability of the model to quantitatively describe NO production in ECs were compared and validated with reported experimental data. According to the validated model, inhibition of protein kinase B (AKT) phosphorylation and Ca2+ influx by dynamic oscillatory WSS disrupts the dual nature of endothelial nitric oxide synthase (eNOS) enzyme activation. This disruption leads to the decrease in NO production and the bimodal disappearance of NO waveforms. Moreover, the results reveal that dynamic WSS combined with insulin promote endothelial NO production through negative synergistic effects, which is resulted from the temporal differences in mechanical and biochemical signaling. In brief, the proposed model elucidates the mechanism of NO generation activated by dynamic WSS combined with insulin, providing a potential target and theoretical framework for future treatment of DVCs.

Insulin resistance surrogates are associated with all-cause mortality and cardiovascular mortality in population with metabolic syndrome: a retrospective cohort study of NHANES

The study aimed to assess the association of five insulin resistance surrogates, namely HOMA-β (Homeostasis Model Assessment of Beta-cell Function), QUICKI (Quantitative Insulin Sensitivity Check Index), IGR (Insulin Glucose Ratio), e-IS (Estimated Insulin Sensitivity), and Bennett ISI(Bennett's insulin sensitivity index) with all-cause and cardiovascular mortality in respondents with metabolic syndrome(MetS). The prospective cohort of 6662 participants aged 18 years and older with metabolic syndrome was extracted from the National Health and Nutrition Examination Survey(NHANES 1999-2016). The multivariate Cox proportional hazards regression model, Kaplan-Meier survival curve, and log-rank tests were applied to determine the association between the five indices and all-cause mortality and cardiovascular mortality in the MetS population. Restricted cubic splines, a two-piece segmented Cox proportional hazards model, and threshold effect analyses were performed to evaluate the nonlinear relationship. Sensitivity analyses were then conducted by removing individuals with CKD, CHF, CAD, stroke, or cancer, respectively. All five insulin resistance (IR) surrogates displayed a negative association with all-cause and cardiovascular mortality in participants with metabolic syndrome. Restricted cubic spline curves showed QUICKI, IGR, and e-IS had a nonlinear relationship with statistical significance. MetS population at the highest quartile of HOMA-β or IGR exhibited lower all-cause and cardiovascular event probabilities compared with those at the lowest quartile, and e-IS had a similar correlation with cardiovascular events. Threshold effect analyses showed that there were inflection points of IGR for all-cause and cardiovascular mortality. As IGR gradually approached inflection points, the two types of mortality risks descended by 15%[HR 0.85(0.80,0.91)] and 19%[HR 0.81(0.71,0.92)], respectively. Sensitivity analysis indicated most results were robust, but Bennett ISI did not exhibit significant outcomes in participants without CKD. Our study provides evidence that HOMA-β, QUICKI, IGR, e-IS, and Bennett ISI displayed a reverse correlation with all-cause mortality and cardiovascular mortality in participants with metabolic syndrome. The five IR surrogates should be given more attention during the follow-up of MetS population.

Endothelial versus Metabolic Insulin Resistance, A Descriptive Review

Cardiovascular complications are a primary focus in the clinical management of type 2 diabetes, as they are the leading causes of disability and mortality in individuals with diabetes. Insulin resistance and endothelial dysfunction commonly coexist in diabetic patients. An increasing body of research indicates a reciprocal and interconnected association between endothelial function and insulin resistance. Insulin resistance can manifest in two distinct forms: endothelial and metabolic, with the former predominantly affecting vascular endothelial cells and the latter primarily impacting peripheral cells. The understanding of endothelial insulin resistance is crucial in comprehending the pathophysiology of cardiovascular complications in type 2 diabetes. Hence, the objective of this study is to examine the correlations, interplays, and molecular pathways linking endothelial insulin resistance and metabolic insulin resistance, with the aim of offering novel insights and scholarly resources for the prevention and management of diabetic vascular complications.

Endothelial Dysfunction and Cardiovascular Disease: Hyperbaric Oxygen Therapy as an Emerging Therapeutic Modality?

Maintaining the physiological function of the vascular endothelium and endothelial glycocalyx is crucial for the prevention of cardiovascular disease, which is one of the leading causes of morbidity and mortality worldwide. Damage to these structures can lead to atherosclerosis, hypertension, and other cardiovascular problems, especially in individuals with risk factors such as diabetes and obesity. Endothelial dysfunction is associated with ischemic disease and has a negative impact on overall cardiovascular health. The aim of this review was to comprehensively summarize the crucial role of the vascular endothelium and glycocalyx in cardiovascular health and associated thrombo-inflammatory conditions. It highlights how endothelial dysfunction, influenced by factors such as diabetes, chronic kidney disease, and obesity, leads to adverse cardiovascular outcomes, including heart failure. Recent evidence suggests that hyperbaric oxygen therapy (HBOT) may offer therapeutic benefits in the treatment of cardiovascular risk factors and disease. This review presents the current evidence on the mechanisms by which HBOT promotes angiogenesis, shows antimicrobial and immunomodulatory effects, enhances antioxidant defenses, and stimulates stem cell activity. The latest findings on important topics will be presented, including the effects of HBOT on endothelial dysfunction, cardiac function, atherosclerosis, plaque stability, and endothelial integrity. In addition, the role of HBOT in alleviating cardiovascular risk factors such as hypertension, aging, obesity, and glucose metabolism regulation is discussed, along with its impact on inflammation in cardiovascular disease and its potential benefit in ischemia-reperfusion injury. While HBOT demonstrates significant therapeutic potential, the review also addresses potential risks associated with excessive oxidative stress and oxygen toxicity. By combining information on the molecular mechanisms of HBOT and its effects on the maintenance of vascular homeostasis, this review provides valuable insights into the development of innovative therapeutic strategies aimed at protecting and restoring endothelial function to prevent and treat cardiovascular diseases.

Evaluation of Triglyceride Glucose Index in Patients with Patent Foramen Ovale Who Experienced Cryptogenic Stroke

Background/Objectives: The prevalence of patent foramen ovale (PFO) has been found to be increased in patients with cryptogenic stroke, suggesting an association between these two clinical settings. Insulin resistance is a risk factor for the occurrence of stroke. The triglyceride glucose (TyG) index is a biomarker that reflects the IR status of the body. Our aim was to evaluate the TyG index values in patients with PFO who experienced cryptogenic stroke. Methods: One hundred and twenty nine patients with PFO who experienced embolic stroke and one hundred and eight control subjects were enrolled. All patients in the study group experienced embolic stroke within 2 weeks of enrollment. The TyG index value of each patient was calculated. Results: Patients with stroke were significantly older, had higher levels of glucose, creatinine, triglyceride (TG), leukocyte, and TyG index and lower high-density lipoprotein-cholesterol values. The TyG index had the highest sensitivity for the prediction of stroke in comparison to TG and glucose values. Comparison of ROC curves showed that the TyG index had the highest AUC compared to that of TG and glucose. The TyG index value of 8.89 predicted stroke occurrence with a sensitivity and specificity of 63.2% and 72.3%, respectively. The results of multivariable regression analyses showed that the TyG index had a higher odds ratio than TG, which indicated that it had a better predictive value. Conclusions: Assessment of the TyG index in cryptogenic stroke patients with PFO might be helpful for the management of these patients.

Joint association of METS-IR and uric acid with stoke, mediated by C-reactive protein

Objectives

To explore the dose-response relationship between the Metabolic Score of Insulin Resistance (METS-IR), uric acid (UA) and the risk of stroke incidence, the mediating role of C-reactive protein (CRP) in the above relationship, as well as the joint effect of METS-IR and UA on the risk of stroke incidence.

Methods

Participants from the CHARLS study were included in this cohort study. Logistic regression models were used to estimate the odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for the associations of METS-IR and UA with the risk of incident stroke. The dose-response relationships of METS-IR and UA with stroke risk were assessed by restricted cubic spline regression. The mediation models were employed to estimate the potential mediating effects of CRP on the associations of METS-IR and UA with stroke risk. Logistic regression analysis was carried out to analyse the association of stroke and MRTS-IR combined with UA.

Result

During a 9-year follow-up from 2011 to 2018, 570 incident cases of stroke were documented among 7,343 total participants. Per interquartile range increases in METS-IR and UA were associated with the increased risk of incident stroke, with the OR (95% CI) of 1.61 (1.44, 1.80) and 1.18 (1.05, 1.32) respectively. A dose-response function showed that METS-IR had a nonlinear relationship (P for nonlinear=0.047) and UA had a linear relationship (P for nonlinear=0.247) with the stroke risk. CRP had significant mediated effects on the associations of METS-IR and UA with stroke risk, and the proportion of mediation was 9.01% and 26.34% respectively (all P < 0.05). The results of joint effect showed that participants with high levels of METS-IR and UA had the highest increased risk of stroke compared to the participants with low levels of METS-IR and UA.

Conclusion

METS-IR and UA levels were positively associated with an increased risk of stroke onset, and CRP mediated these relationships. Improving insulin sensitivity and regulating CRP and uric acid levels may be important for preventing the risk of stroke occurrence.

An innovative metabolic index for insulin resistance correlates with early neurological deterioration following intravenous thrombolysis in minor acute ischemic stroke patients

Background and purpose

The composite score for insulin resistance (IR), known as the Metabolic Score of Insulin Resistance (METS-IR), serves as an assessment tool for IR and has been previously linked to symptomatic intracranial hemorrhage and poor functional outcomes in patients with acute ischemic stroke (AIS). Despite these associations, the impact of METS-IR on early neurological deterioration (END) in patients with minor AIS who underwent intravenous administration of recombinant tissue-type plasminogen activator (IV-rtPA) remains inadequately established. This investigation explored the link between METS-IR and END in patients with minor AIS receiving IV-rtPA treatment.

Methods

In this study, a cohort comprising 425 consecutive patients with National Institutes of Health Stroke Scale Score (NIHSS)≤5 who underwent IV-rtPA treatment was included. The METS-IR was computed using the formula ln METS-IR=ln (2 × FBG + TG) × BMI/ln (HDL). END was defined as a NIHSS ≥2 within 24 h post IV-rtPA administration, while poor functional outcome was defined as a modified Rankin Scale (mRS) of 2-6. Multivariate logistical regression was performed to investigate the association between METS-IR and both poor functional outcomes and END.

Results

Among the 425 enrolled patients, 64 (15.1 %) patients experienced END, while 80 (18.8 %) had poor functional outcomes three months post-discharge. Upon adjusting for confounding factors, a higher METS-IR emerged as an independent predictor for both END and poor functional outcomes. Similarly, noteworthy findings were observed when METS-IR was defined as a categorical group. The restricted cubic spline (RCS) analysis indicated a linear relationship between METS-IR and END (P = 0.593 for non-linearity, P = 0.034 for overall). The incorporation of METS-IR into the conventional model resulted in a significant enhancement of predictive accuracy for both END and poor functional outcomes.

Conclusion

METS-IR emerges as an independent predictor for END and poor functional outcome at three months post-discharge in patients with minor AIS subjected to IV-rtPA. Considering its simplicity and clinical accessibility as an indicator of IR, METS-IR may hold guiding significance in clinical practice.

The association of triglyceride-glucose index and combined obesity indicators with chest pain and risk of cardiovascular disease in American population with pre-diabetes or diabetes

Aim

To investigate the correlation of the triglyceride-glucose (TyG) index and its combined obesity indicators with chest pain and cardiovascular disease (CVD) in the pre-diabetes and diabetes population.

Methods

This cross-sectional investigation encompassed 6488 participants with diabetes and pre-diabetes who participated in the National Health and Nutrition Examination Survey (NHANES) between 2007 and 2016. The association of the TyG and combined obesity index with chest pain and CVD was investigated using weighted logistic regression models and restricted cubic spline (RCS) analysis. The receiver operating characteristic (ROC) curve analysis was performed to compare different indicators.

Results

In multivariate logistic regression fully adjusted for confounding variables, our analyses revealed significant associations between TyG, TyG-BMI, TyG-WC, and TyG-WHtR and chest pain, with adjusted ORs (95% CI) of 1.21 (1.05, 1.39), 1.06 (1.01, 1.11), 1.08 (1.04, 1.14), and 1.27 (1.08, 1.48), respectively. For total-CVD, the adjusted ORs (95% CI) were 1.32 (1.08, 1.61), 1.10 (1.03, 1.17), 1.13 (1.06, 1.19), and 1.63 (1.35, 1.97), respectively, among which TyG, TyG-WC, and TyG-WHtR present curvilinear associations in RCS analysis (all P-nonlinear < 0.05). Furthermore, the ROC curve showed that TyG-WC had the most robust predictive efficacy for total-CVD, coronary heart disease (CHD), and myocardial infarction (MI), while TyG-WHtR had the best predictive ability for angina and heart failure.

Conclusion

There are significant associations of TyG and its related indicators with chest pain and total-CVD among the pathoglycemia population. TyG-WC and TyG-WHtR demonstrated superior predictive capability for the incidence of cardiovascular events.

Predicting gestational diabetes mellitus risk at 11-13 weeks' gestation: the role of extrachromosomal circular DNA

BACKGROUND

Gestational diabetes mellitus (GDM) significantly impacts maternal and infant health both immediately and over the long term, yet effective early diagnostic biomarkers are currently lacking. Thus, it is essential to identify early diagnostic biomarkers for GDM risk screening. Extrachromosomal circular DNA (eccDNA), being more stable than linear DNA and involved in disease pathologies, is a viable biomarker candidate for diverse conditions. In this study, eccDNA biomarkers identified for early diagnosis and assessment of GDM risk were explored.

METHODS

Using Circle-seq, we identified plasma eccDNA profiles in five pregnant women who later developed GDM and five matched healthy controls at 11-13 weeks of gestation. These profiles were subsequently analyzed through bioinformatics and validated through outward PCR combined with Sanger sequencing. Furthermore, candidate eccDNA was validated by quantitative PCR (qPCR) in a larger cohort of 70 women who developed GDM and 70 normal glucose-tolerant (NGT) subjects. A ROC curve assessed the eccDNA's diagnostic potential for GDM.

RESULTS

2217 eccDNAs were differentially detected between future GDM patients and controls, with 1289 increased and 928 decreased in abundance. KEGG analysis linked eccDNA genes mainly to GDM-related pathways such as Rap1, MAPK, and PI3K-Akt, and Insulin resistance, among others. Validation confirmed a significant decrease in eccDNA PRDM16circle in the plasma of 70 women who developed GDM compared to 70 NGT women, consistent with the eccDNA-seq results. PRDM16circle showed significant diagnostic value in 11-13 weeks of gestation (AUC = 0.941, p < 0.001).

CONCLUSIONS

Our study first demonstrats that eccDNAs are aberrantly produced in women who develop GDM, including PRDM16circle, which can predict GDM at an early stage of pregnancy, indicating its potential as a biomarker.

TRIAL REGISTRATION

ChiCTR2300075971, http://www.chictr.org.cn . Registered 20 September 2023.

Insulin-Heart Axis: Bridging Physiology to Insulin Resistance

Insulin signaling is vital for regulating cellular metabolism, growth, and survival pathways, particularly in tissues such as adipose, skeletal muscle, liver, and brain. Its role in the heart, however, is less well-explored. The heart, requiring significant ATP to fuel its contractile machinery, relies on insulin signaling to manage myocardial substrate supply and directly affect cardiac muscle metabolism. This review investigates the insulin-heart axis, focusing on insulin's multifaceted influence on cardiac function, from metabolic regulation to the development of physiological cardiac hypertrophy. A central theme of this review is the pathophysiology of insulin resistance and its profound implications for cardiac health. We discuss the intricate molecular mechanisms by which insulin signaling modulates glucose and fatty acid metabolism in cardiomyocytes, emphasizing its pivotal role in maintaining cardiac energy homeostasis. Insulin resistance disrupts these processes, leading to significant cardiac metabolic disturbances, autonomic dysfunction, subcellular signaling abnormalities, and activation of the renin-angiotensin-aldosterone system. These factors collectively contribute to the progression of diabetic cardiomyopathy and other cardiovascular diseases. Insulin resistance is linked to hypertrophy, fibrosis, diastolic dysfunction, and systolic heart failure, exacerbating the risk of coronary artery disease and heart failure. Understanding the insulin-heart axis is crucial for developing therapeutic strategies to mitigate the cardiovascular complications associated with insulin resistance and diabetes.

Peripheral whole blood microRNA expression in relation to vascular function: a population-based study

BACKGROUND

As key regulators of gene expression, microRNAs affect many cardiovascular mechanisms and have been associated with several cardiovascular diseases. In this study, we aimed to investigate the relation of whole blood microRNAs with several quantitative measurements of vascular function, and explore their biological role through an integrative microRNA-gene expression analysis.

METHODS

Peripheral whole blood microRNA expression was assessed through RNA-Seq in 2606 participants (45.8% men, mean age: 53.93, age range: 30 to 95 years) from the Rhineland Study, an ongoing population-based cohort study in Bonn, Germany. Weighted gene co-expression network analysis was used to cluster microRNAs with highly correlated expression levels into 14 modules. Through linear regression models, we investigated the association between each module's expression and quantitative markers of vascular health, including pulse wave velocity, total arterial compliance index, cardiac index, stroke index, systemic vascular resistance index, reactive skin hyperemia and white matter hyperintensity burden. For each module associated with at least one trait, one or more hub-microRNAs driving the association were defined. Hub-microRNAs were further characterized through mapping to putative target genes followed by gene ontology pathway analysis.

RESULTS

Four modules, represented by hub-microRNAs miR-320 family, miR-378 family, miR-3605-3p, miR-6747-3p, miR-6786-3p, and miR-330-5p, were associated with total arterial compliance index. Importantly, the miR-320 family module was also associated with white matter hyperintensity burden, an effect partially mediated through arterial compliance. Furthermore, hub-microRNA miR-192-5p was related to cardiac index. Functional analysis corroborated the relevance of the identified microRNAs for vascular function by revealing, among others, enrichment for pathways involved in blood vessel morphogenesis and development, angiogenesis, telomere organization and maintenance, and insulin secretion.

CONCLUSIONS

We identified several microRNAs robustly associated with cardiovascular function, especially arterial compliance and cardiac output. Moreover, our results highlight miR-320 as a regulator of cerebrovascular damage, partly through modulation of vascular function. As many of these microRNAs were involved in biological processes related to vasculature development and aging, our results contribute to the understanding of vascular physiology and provide putative targets for cardiovascular disease prevention.

Innovative Treatments to Counteract Endothelial Dysfunction in Chronic Kidney Disease Patients

In chronic kidney disease (CKD) patients, several risk factors contribute to the development of endothelial dysfunction (ED), which can be described as an alteration in the cell structure or in the function of the endothelium. Among the well-known CKD-related risk factors capable of altering the production of endothelium-derived relaxing factors, we include asymmetric dimethylarginine increase, reduced dimethylarginine dimethylamine hydrolase enzyme activity, low-grade chronic systemic inflammation, hyperhomocysteinemia, oxidative stress, insulin resistance, alteration of calcium phosphorus metabolism, and early aging. In this review, we also examined the most important techniques useful for studying ED in humans, which are divided into indirect and direct methods. The direct study of coronary endothelial function is considered the gold standard technique to evaluate if ED is present. In addition to the discussion of the main pharmacological treatments useful to counteract ED in CKD patients (namely sodium-glucose cotransporter 2 inhibitors and mineralocorticoid receptor antagonist), we elucidate innovative non-pharmacological treatments that are successful in accompanying the pharmacological ones. Among them, the most important are the consumption of extra virgin olive oil with high intake of minor polar compounds, adherence to a plant-dominant, low-protein diet (LPD), an adaptive physical activity program and, finally, ketoanalogue administration in combination with the LPD or the very low-protein diet.

Insulin resistance before type 2 diabetes onset is associated with increased risk of albuminuria after diabetes onset: A prospective cohort study

AIM

Reduced renal insulin signalling is implicated in the pathogenesis of albuminuria. We sought to investigate whether insulin action and secretion, measured before diabetes onset, are associated with the development of albuminuria after diabetes onset.

MATERIALS AND METHODS

Baseline body composition, insulin sensitivity by hyperinsulinaemic-euglycaemic clamp at submaximal and maximal insulin stimulation (240 and 2400 pmol/m2/min; M-low and M-high), and insulin secretion by intravenous glucose tolerance test [acute insulin response (AIR)] were measured in 170 Southwestern Indigenous American adults who subsequently developed diabetes. After diabetes onset and during the median follow-up of 13.6 years, 81 participants (48%) developed albuminuria (urine albumin-to-creatinine ratio ≥30 mg/g). Separate associations of M-low, M-high and AIR (per 1-SD change) with the risk of albuminuria were assessed by Cox regression models adjusted for age, sex and body fat (%).

RESULTS

Participants who developed albuminuria were of similar age (26.4 ± 5.4 vs. 27.5 ± 6.1 years), sex (46% vs. 48% male), body fat (36.4 ± 7.5 vs. 35.7 ± 7.9%) and AIR [2.3 ± 0.3 vs. 2.3 ± 0.3, pmol/L (log)] as those who did not develop albuminuria but had lower insulin sensitivity [M-low: 0.33 ± 0.08 vs. 0.36 ± 0.12, p = .03; M-high: 0.87 ± 0.11 vs. 0.91 ± 0.12, p = .02; mg/kg-metabolic body size/min (log)]. In separate adjusted models, lower M-low and M-high were both associated with an increased risk for albuminuria [hazard ratio (HR) 1.51, 95% confidence interval (CI) 1.14, 2.00, p = .004; HR 1.31, 95% CI 1.06, 1.63, p = .01), whereas AIR was not (HR 1.15, 95% CI 0.87, 1.56, p = .3).

CONCLUSIONS

Lower insulin sensitivity is associated with the development of albuminuria, suggesting a role for insulin signalling in the pathogenesis of proteinuria.

A systematic review of astragaloside IV effects on animal models of diabetes mellitus and its complications

Context

Diabetes mellitus (DM) is one of the fastest-growing diseases worldwide; however, its pathogenesis remains unclear. Complications seriously affect the quality of life of patients in the later stages of diabetes, ultimately leading to suffering. Natural small molecules are an important source of antidiabetic agents.

Objective

Astragaloside IV (AS-IV) is an active ingredient of Astragalus mongholicus (Fisch.) Bunge. We reviewed the efficacy and mechanism of action of AS-IV in animal and cellular models of diabetes and the mechanism of action of AS-IV on diabetic complications in animal and cellular models. We also summarized the safety of AS-IV and provided ideas and rationales for its future clinical application.

Methods

Articles on the intervention in DM and its complications using AS-IV, such as those published in SCIENCE, PubMed, Springer, ACS, SCOPUS, and CNKI from the establishment of the database to February 2022, were reviewed. The following points were systematically summarized: dose/concentration, route of administration, potential mechanisms, and efficacy of AS-IV in animal models of DM and its complications.

Results

AS-IV has shown therapeutic effects in animal models of DM, such as alleviating gestational diabetes, delaying diabetic nephropathy, preventing myocardial cell apoptosis, and inhibiting vascular endothelial dysfunction; however, the potential effects of AS-IV on DM should be investigated.

Conclusion

AS-IV is a potential drug for the treatment of diabetes and its complications, including diabetic vascular disease, cardiomyopathy, retinopathy, peripheral neuropathy, and nephropathy. In addition, preclinical toxicity studies indicate that it appears to be safe, but the safe human dose limit is yet to be determined, and formal assessments of adverse drug reactions among humans need to be further investigated. However, additional formulations or structural modifications are required to improve the pharmacokinetic parameters and facilitate the clinical use of AS-IV.

Primordial Drivers of Diabetes Heart Disease: Comprehensive Insights into Insulin Resistance

Insulin resistance has been regarded as a hallmark of diabetes heart disease (DHD). Numerous studies have shown that insulin resistance can affect blood circulation and myocardium, which indirectly cause cardiac hypertrophy and ventricular remodeling, participating in the pathogenesis of DHD. Meanwhile, hyperinsulinemia, hyperglycemia, and hyperlipidemia associated with insulin resistance can directly impair the metabolism and function of the heart. Targeting insulin resistance is a potential therapeutic strategy for the prevention of DHD. Currently, the role of insulin resistance in the pathogenic development of DHD is still under active research, as the pathological roles involved are complex and not yet fully understood, and the related therapeutic approaches are not well developed. In this review, we describe insulin resistance and add recent advances in the major pathological and physiological changes and underlying mechanisms by which insulin resistance leads to myocardial remodeling and dysfunction in the diabetic heart, including exosomal dysfunction, ferroptosis, and epigenetic factors. In addition, we discuss potential therapeutic approaches to improve insulin resistance and accelerate the development of cardiovascular protection drugs.

Cardiometabolic Risk Factors Associated With Type 2 Diabetes Mellitus: A Mechanistic Insight

A complex metabolic condition referred to as Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance (IR) and decreased insulin production. Obesity, dyslipidemia, hypertension, and chronic inflammation are just a few of the cardiometabolic illnesses that people with T2DM are more likely to acquire and results in cardiovascular issues. It is essential to comprehend the mechanistic insights into these risk variables in order to prevent and manage cardiovascular problems in T2DM effectively. Impaired glycemic control leads to upregulation of De novo lipogenesis (DNL), promote hepatic triglyceride (TG) synthesis, worsening dyslipidemia that is accompanied by low levels of high density lipoprotein cholesterol (HDL-C) and high amounts of small, dense low-density lipoprotein cholesterol (LDL-C) further developing atherosclerosis. By causing endothelial dysfunction, oxidative stress, and chronic inflammation, chronic hyperglycemia worsens already existing cardiometabolic risk factors. Vasoconstriction, inflammation, and platelet aggregation are caused by endothelial dysfunction, which is characterized by decreased nitric oxide production, increased release of vasoconstrictors, proinflammatory cytokines, and adhesion molecules. The loop of IR and endothelial dysfunction is sustained by chronic inflammation fueled by inflammatory mediators produced in adipose tissue. Infiltrating inflammatory cells exacerbate inflammation and the development of plaque in the artery wall. In addition, the combination of chronic inflammation, dyslipidemia, and IR contributes to the emergence of hypertension, a prevalent comorbidity in T2DM. The ability to target therapies and management techniques is made possible by improvements in our knowledge of these mechanistic insights. Aim of present review is to enhance our current understanding of the mechanistic insights into the cardiometabolic risk factors related to T2DM provides important details into the interaction of pathophysiological processes resulting in cardiovascular problems. Understanding these pathways will enable us to create efficient plans for the prevention, detection, and treatment of cardiovascular problems in T2DM patients, ultimately leading to better overall health outcomes.

Longitudinal trajectories of atherogenic index of plasma and risks of cardiovascular diseases: results from the Korean genome and epidemiology study

BACKGROUND

Although the atherogenic index of plasma (AIP) based on a single measurement is a known risk factor for cardiovascular disease (CVD), little is known about whether changes in AIP over time are related to incident CVD. We aimed to determine whether AIP trajectory, which reflects homogenous AIP trends for a particular period, is associated with CVD risk.

METHODS

Data from 5,843 participants of the Korean Genome and Epidemiology Study (KoGES) were analyzed. The KoGES had been conducted biennially from the baseline survey (2001-2002) to the eighth follow-up survey (2017-2018). The research design specifies the exposure period from baseline to the third follow-up, designates the latent period at the fourth follow-up, and establishes the event accrual period from the fifth to the eighth follow-up. During the exposure period, we identified two trajectories: a decreasing (n = 3,036) and an increasing group (n = 2,807) using latent variable mixture modeling. Information on CVD was collected initially through the self-reporting, followed by in depth person-to-person interview conducted by a well-trained examiner. During the event accrual period, the cumulative incidence rates of CVD between the two AIP trajectory groups were estimated using Kaplan-Meier analysis with the log-rank test. Multiple Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

The increasing AIP trajectory group had a significantly higher cumulative incidence rate of CVD than the decreasing AIP trajectory group. Compared to the decreasing AIP trajectory group, the increasing AIP trajectory group had a higher risk of incident CVD (HR: 1.31, 95% CI: 1.02-1.69) after adjusting for confounders.

CONCLUSIONS

The risk of incident CVD increased when the AIP level showed an increasing trend and remained high over a long period. This suggests that checking and managing the trajectory of the AIP can be a preventive strategy for incident CVD.

Which Comes First, Nonalcoholic Fatty Liver Disease or Arterial Hypertension?

Non-alcoholic fatty liver disease (NAFLD) and arterial hypertension (AH) are widespread noncommunicable diseases in the global population. Since hypertension and NAFLD are diseases associated with metabolic syndrome, they are often comorbid. In fact, many contemporary published studies confirm the association of these diseases with each other, regardless of whether other metabolic factors, such as obesity, dyslipidemia, and type 2 diabetes mellites, are present. This narrative review considers the features of the association between NAFLD and AH, as well as possible pathophysiological mechanisms.

Role of Epigenetics and Metabolomics in Predicting Endothelial Dysfunction in Type 2 Diabetes

Type 2 diabetes (T2D) is a worldwide health problem and cardiovascular disease (CVD) is a leading cause of morbidity and mortality in T2D patients, making the prevention of CVD onset a major priority. It is therefore crucial to optimize diagnosis and treatment to reduce this burden. Endothelial dysfunction is one of the most important prognostic factors for CVD progression, thus novel approaches to identify the early phase of endothelial dysfunction may lead to specific preventive measures to reduce the occurrence of CVD. Nowadays, multiomics approaches have provided unprecedented opportunities to stratify T2D patients into endotypes, improve therapeutic treatment and outcome and amend the survival prediction. Among omics strategies, epigenetics and metabolomics are gaining increasing interest. Recently, a dynamic correlation between metabolic pathways and gene expression through chromatin remodeling, such as DNA methylation, has emerged, indicating new perspectives on the regulatory networks impacting cellular processes. Thus, a better understanding of epigenetic-metabolite relationships can provide insight into the physiological processes altered early in the endothelium that ultimately head to disease development. Here, recent studies on epigenetics and metabolomics related to CVD prevention potentially useful to identify disease biomarkers, as well as new therapies hopefully targeting the early phase of endothelial dysfunction are highlighted.

Triglyceride-glucose index predicts death in patients with stroke younger than 65

Background

The triglyceride-glucose index (TGI), a reliable surrogate indicator of insulin resistance (IR), has been proven to be a predictor of the incidence of ischemic stroke. The role of TGI in predicting the outcomes of stroke patients remains controversial. Susceptibility to IR-related diseases varies among patients of different ages. The study aims to evaluate the predictive value of TGI levels on clinical outcomes of patients with ischemic stroke of different ages.

Method

This was a retrospective cohort study including patients with ischemic stroke in the Department of Neurology at West China Hospital. TGI was calculated as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. The patients were subdivided into 3 tertiles according to TGI levels. Multivariate logistic regression analyses were conducted to estimate the association between TGI levels and post-stroke outcomes among the whole patients, younger patients (<65), and older patients (>=65). The outcomes included death and unfavorable functional outcome (modified Rankin scale score 3-6) at 3 and 12 months after stroke.

Results

A total of 3,704 patients (men, 65.08%, mean age, 61.44 ± 14.15; women 34.92%, mean age, 65.70 ± 13.69) were enrolled in this study. TGI levels were not associated with 3 month or 12 month death in the whole patients. Patients with higher TGI levels (T2 and T3) had a higher risk of 3 month death than those had lower TGI levels (T1) in the younger group (T2 vs. T1: OR 2.64, 95% CI 1.03-6.79, p = 0.043; T3 vs. T1: OR 2.69, 95% CI 1.00-7.10, p = 0.049) but not in the older group. Additionally, Kaplan-Meier estimate analysis illustrated that the 12 month death risk was significantly higher in the group with the highest TGI among younger patients (p for log-rank test = 0.028) but not among older patients. There was an interactive effect between TGI and age on 3 month death (p for interaction = 0.013) and 12 month death (p for interaction = 0.027). However, TGI was not associated with unfavorable functional outcome at 3 month or 12 month after stroke.

Conclusion

Elevated TGI independently predicts death at 3 months and 12 months in patients under 65 with ischemic stroke. Regulating TGI is expected to be an approach to enhance prognosis in young individuals affected by ischemic stroke.

Mitigation effect of galangin against aortic dysfunction and hypertrophy in rats with metabolic syndrome

Vascular alterations induced by a high-fat diet (HFD) are involved in the development of hypertension. Galangin, a flavonoid, is the major active compound isolated from galangal and propolis. The objective of this study was to investigate the effect of galangin on aortic endothelial dysfunction and hypertrophy, and the mechanisms involved in HFD-induced metabolic syndrome (MS) in rats. Male Sprague-Dawley rats (220-240 g) were separated into three groups: control + vehicle, MS + vehicle, and MS + galangin (50 mg/kg). Rats with MS received HFD plus 15% fructose solution for 16 weeks. Galangin or vehicle was orally administered daily for the final four weeks. Galangin reduced body weight and mean arterial pressure in HFD rats (p < 0.05). It also reduced circulating fasting blood glucose, insulin, and total cholesterol levels (p < 0.05). Impaired vascular responses to the exogenous acetylcholine observed in the aortic ring of HFD rats were restored by galangin (p < 0.05). However, the response to sodium nitroprusside did not differ between the groups. Galangin enhanced the expression of the aortic endothelial nitric oxide synthase (eNOS) protein and increased circulating nitric oxide (NO) levels in the MS group (p < 0.05). Aortic hypertrophy in HFD rats was alleviated by galangin (p < 0.05). Increases in tumour necrosis factor-alpha (TNF-α), interleukin (IL)-6 levels, angiotensin-converting enzyme activity and angiotensin II (Ang II) concentrations in rats with MS were suppressed in galangin treated group (p < 0.05). Furthermore, galangin reduced the upregulation of angiotensin II type I receptor (AT1R) and transforming growth factor-beta (TGF-β) expression in rats with MS (p < 0.05). In conclusion, galangin alleviates metabolic disorders and improves aortic endothelial dysfunction and hypertrophy in the MS group. These effects were consistent with increased NO availability, reduced inflammation, and suppressing Ang II/AT1R/TGF-β signalling pathway.

Cardiovascular complications in insulin resistance and endocrine diseases

Cerebrovascular diseases, such as stroke and cardiovascular disease, are one of the leading causes of death in Japan. Type 2 diabetes is the most common form of diabetes and an important risk factor for these diseases. Among various pathological conditions associated with type 2 diabetes, insulin resistance has already been reported to be an important risk factor for diabetic complications. The major sites of insulin action in glucose metabolism in the body include the liver, skeletal muscle, and adipose tissue. However, insulin signaling molecules are also constitutively expressed in vascular endothelial cells, vascular smooth muscle, and monocytes/macrophages. Forkhead box class O family member proteins (FoxOs) of transcription factors play important roles in regulating glucose and lipid metabolism, oxidative stress response and redox signaling, and cell cycle progression and apoptosis. FoxOs in vascular endothelial cells strongly promote arteriosclerosis by suppressing nitric oxide production, enhancing inflammatory response, and promoting cellular senescence. In addition, primary aldosteronism and Cushing's syndrome are known to have adverse effects on the cardiovascular system, apart from hypertension, diabetes, and dyslipidemia. In the treatment of endocrine disorders, hormonal normalization by surgical treatment and receptor antagonists play an important role in preventing cardiovascular complications.

Pathways of Coagulopathy and Inflammatory Response in SARS-CoV-2 Infection among Type 2 Diabetic Patients

Chronic inflammation and endothelium dysfunction are present in diabetic patients. COVID-19 has a high mortality rate in association with diabetes, partially due to the development of thromboembolic events in the context of coronavirus infection. The purpose of this review is to present the most important underlying pathomechanisms in the development of COVID-19-related coagulopathy in diabetic patients. The methodology consisted of data collection and synthesis from the recent scientific literature by accessing different databases (Cochrane, PubMed, Embase). The main results are the comprehensive and detailed presentation of the very complex interrelations between different factors and pathways involved in the development of arteriopathy and thrombosis in COVID-19-infected diabetic patients. Several genetic and metabolic factors influence the course of COVID-19 within the background of diabetes mellitus. Extensive knowledge of the underlying pathomechanisms of SARS-CoV-2-related vasculopathy and coagulopathy in diabetic subjects contributes to a better understanding of the manifestations in this highly vulnerable group of patients; thus, they can benefit from a modern, more efficient approach regarding diagnostic and therapeutic management.

The Value of RBP4 in Assessing Coronary Artery Elasticity in Patients with Coronary Heart Disease and Type 2 Diabetes Mellitus

Background

Existing research has shown that retinol binding protein (RBP4) has an impairing effect on arterial elasticity and induces insulin resistance, but the clinical value of RBP4 in patients with coronary heart disease (CHD) combined with type 2 diabetes mellitus (T2DM) has not been investigated. This study sought to compare the complexity of coronary artery lesions and coronary artery elasticity between patients with CHD combined with T2DM and those with CHD without T2DM, analyze the risk factors affecting coronary artery elasticity, and investigate the value of RBP4 in assessing coronary artery elasticity in patients with CHD and T2DM.

Methods

A total of 130 patients with confirmed CHD were consecutively enrolled, including 38 patients with CHD combined with T2DM and 92 patients with CHD without T2DM. Basic clinical data, laboratory findings, coronary angiography and intravascular ultrasound (IVUS) imaging data, and Gensini scores and coronary artery elasticity parameters were calculated in both groups. Elasticity parameters included: stiffness parameter ( β ), pressure-strain elastic modulus ( E p ), distensibility coefficient (DC), and compliance coefficient (CC). Multiple linear regression equations were established with elasticity parameters as dependent variables to explore the factors influencing coronary artery elasticity parameters in patients within the two groups.

Results

Compared with patients in the CHD without T2DM group, patients in the CHD combined with T2DM group had higher RBP4 levels, Gensini scores, β and E p values, and lower DC and CC values. Linear regression analysis showed that Gensini score increased with higher β and E p values and decreased with higher DC and CC values. In all patients in the CHD and CHD combined with T2DM groups, RBP4 was an independent risk factor for β values after correction for confounders by multiple linear regression analysis, whereas in patients in the CHD without T2DM group, the effect of RBP4 on β values was not statistically different.

Conclusions

RBP4 was an independent risk factor of coronary artery elasticity in CHD patients with T2DM and in overall CHD patients, but it did not affect coronary artery elasticity in CHD patients without T2DM.

Circulating Nitric Oxide and Metabolic Syndrome in Arab Children and Adolescents: A Case-Control Study

BACKGROUND

Metabolic syndrome (MetS) represents a cluster of known cardiometabolic risk factors, which elevates the risk of type 2 diabetes mellitus (T2DM), atherosclerotic cardiovascular disease (CVD) and chronic kidney disease (CKD) in adults and, only recently, even in children and adolescents. Circulating nitric oxide (NOx) has been observed to influence MetS risk factors in adults, but this has been scarcely investigated in children. The aim of the present study was to determine whether circulating NOx levels correlate with known components of MetS in Arab children and adolescents.

METHODS

Anthropometrics, serum NOx, lipid profile and fasting glucose levels were measured in 740 Saudi Arabs aged 10-17 years (68.8% girls). The presence of MetS was screened using the criteria of de Ferranti et al. Results: Overall, serum NOx levels were significantly higher in MetS participants compared to non-MetS (25.7 µmol/L (10.1-46.7) versus 11.9 µmol/L (5.5-22.9), p < 0.001) even after adjustments for age, BMI and sex. With the exception of elevated blood pressure, higher circulating NOx significantly increased the odds for MetS and its components. Lastly, receiver operating characteristics (ROC) showed that NOx, as a diagnostic marker for MetS, had good sensitivity and was higher in boys than girls (all MetS participants: area under the curve (AUC) = 0.68, p < 0.001), (girls with MetS: AUC = 0.62, p = 0.002), (boys with MetS: AUC = 0.83, p < 0.001)).

CONCLUSIONS

MetS and most of its components were significantly associated with circulating NOx levels in Arab adolescents and may be a promising diagnostic biomarker for MetS.

Insulin Signaling Pathway Model in Adipocyte Cells

BACKGROUND

Worldwide, type 2 diabetes mellitus (T2DM) is one of the most pervasive and fastgrowing disorders, bringing long-term adverse effects. T2DM arises from pancreatic β-cells deficiency to produce enough insulin or when the body cannot effectively use the insulin produced by such cells. Accordingly, early diagnosis will decrease the long-term effects and high-healthcare costs of diabetes.

OBJECTIVE

The objective is developing an integrated mathematical model of the insulin signaling network based on Brännmark's model, which can simulate the signaling events more comprehensively with the added key components.

METHODS

In this study, a thorough mathematical model of the insulin signaling network was developed by expanding the previously validated model and incorporating the glycogen synthesis module. Parameters (69 parameters) of the integrated model were evaluated by a genetic algorithm by fitting the model predictions to eighty percent of experimental data from the literature. Twenty percent of the experimental data were used to evaluate the final optimized model.

RESULTS

The time-response curves indicate that the GS phosphorylation reaches its maximum in response to 10^-7 M insulin after 4 min, while the maximum phosphorylated GSK3 is attained within ~50 min. The doseresponse curves for the GSP and GSK3 of the insulin signaling intermediaries in response to the increased concentration of insulin, after 10 min, in the input from 0-100 nM exhibits a decreasing trend, whereas an increasing trend was observed for the GS and GSK3P. The GSK and GS phosphorylation sensitivity was enhanced by increasing the initial insulin concentration level from 0.001 to 100 nM. However, the sensitivity of GSK3 to insulin concentration changes (from 0.001 to 100 nM) was 3-fold higher than GS sensitivity.

CONCLUSION

Considerably, the trends of all signaling components simulated by the expanded model shows high compatibility with experimental data (R2 ≥ 0.9), which approves the accuracy of the proposed model. The proposed mathematical model can be used in many biological systems and combined with the whole-body model of the blood glucose regulation system for a better understanding of the causes and potential treatment of type 2 diabetes. Although, this model is not a complete description of insulin signaling, yet it can make profound contributions to improvements regarding other important components and signaling branches such as epidermal growth factor (EGF) signaling, as well as signaling in other cell types in the model structure of future works.

Microscopic image-based classification of adipocyte differentiation by machine learning

Adipocyte differentiation is a sequential process involving increased expression of peroxisome proliferator-activated receptor gamma (PPARγ), adipocyte-specific gene expression, and accumulation of lipid droplets in the cytoplasm. Expression of the transcription factors involved is usually detected using canonical biochemical or biomolecular procedures such as Western blotting or qPCR of pooled cell lysates. While this provides a useful average index for adipogenesis for some populations, the precise stage of adipogenesis cannot be distinguished at the single-cell level, because the heterogenous nature of differentiation among cells limits the utility of averaged data. We have created a classifier to sort cells, and used it to determine the stage of adipocyte differentiation at the single-cell level. We used a machine learning method with microscopic images of cell stained for PPARγ and lipid droplets as input data. Our results show that the classifier can successfully determine the precise stage of differentiation. Stage classification and subsequent model fitting using the sequential reaction model revealed the action of pioglitazone and rosiglitazone to be promotion of transition from the stage of increased PPARγ expression to the next stage. This indicates that these drugs are PPARγ agonists, and that our classifier and model can accurately estimate drug action points and would be suitable for evaluating the stage/state of individual cells during differentiation or disease progression. The incorporation of both biochemical and morphological information derived from immunofluorescence image of cells and so overcomes limitations of current models.

Interaction of FOXO1 and SUMOylated PPARγ1 induced by hyperlipidemia and hyperglycemia favors vascular endothelial insulin resistance and dysfunction

PPARγ1 and FOXO1 are the key transcription factors that regulate insulin sensitivity. We previously found that a small ubiquitin-related modifier of PPARγ1 at K77 (SUMOylation) favored endothelial insulin resistance (IR) induced by high fat/high glucose (HF/HG) administration. However, whether and how the crosstalk between SUMOylated PPARγ1 and FOXO1 would mediate the development of the endothelial IR and dysfunction remains unclear. Here, we emphasize how PPARγ1-K77 SUMOylation would interact with FOXO1 and participate in the development of the endothelial IR and dysfunction. Our results show that the combination of HF/HG and PPARγ1-K77 SUMOylation exhibits a synergistic deteriorative effect on the endothelial IR and dysfunction, presenting decreased NO levels and elevated ET-1 levels, weakened PI3K/Akt/eNOS signaling, and impaired endothelium-dependent vasodilation function. The further researches reveal that PPARγ1-K77 SUMOylation readily interacts with FOXO1, and FOXO1 occupies the PPAR response element (PPRE) which is supposed to be occupied by PPARγ, thus resulting in the decrease of PPARγ1 transcription activity and the mitigation of the PI3K/Akt signaling. Moreover, the mitigation of the PI3K/Akt signaling promotes in turn the accumulation of FOXO1 in the nucleus where FOXO1 interacts with the SUMOylated PPARγ1, thus exerting a positive feedback effect on IR pathogenesis. The findings uncover a novel association between PPARγ1-K77 SUMOylation and FOXO1, which contributes to our understanding of the pathogenesis of endothelial IR and dysfunction and provides novel pharmacological targets for diabetic angiopathy.

Dietary carbohydrates: Pathogenesis and potential therapeutic targets to obesity-associated metabolic syndrome

Metabolic syndrome (MetS) is a common feature in obesity, comprising a cluster of abnormalities including abdominal fat accumulation, hyperglycemia, hyperinsulinemia, dyslipidemia, and hypertension, leading to diabetes and cardiovascular diseases (CVD). Intake of carbohydrates (CHO), particularly a sugary diet that rapidly increases blood glucose, triglycerides, and blood pressure levels is the predominant determining factor of MetS. Complex CHO, on the other hand, are a stable source of energy taking a longer time to digest. In particular, resistant starch (RS) or soluble fiber is an excellent source of prebiotics, which alter the gut microbial composition, which in turn improves metabolic control. Altering maternal CHO intake during pregnancy may result in the child developing MetS. Furthermore, lifestyle factors such as physical inactivity in combination with dietary habits may synergistically influence gene expression by modulating genetic and epigenetic regulators transforming childhood obesity into adolescent metabolic disorders. This review summarizes the common pathophysiology of MetS in connection with the nature of CHO, intrauterine nutrition, genetic predisposition, lifestyle factors, and advanced treatment approaches; it also emphasizes how dietary CHO may act as a key element in the pathogenesis and future therapeutic targets of obesity and MetS.

The triglyceride glucose index is associated with the cerebral small vessel disease in a memory clinic population

BACKGROUND AND OBJECTIVES

Insulin resistance (IR) has been associated with the cerebral small vessel disease (cSVD). However, as the surrogate marker of IR, there is little known about the relationship between the triglyceride glucose (TyG) index and cSVD. In this cross-sectional study, we aimed to evaluate the relationship between the TyG index and cSVD in a memory clinic population and explore the value of TyG index to improve the risk stratification of cSVD.

METHODS

We included participants who attended our memory clinic from January 2016 to December 2020. TyG index was determined as ln [fasting triglyceride (mg/dL) × fasting plasma glucose (mg/dL)/2]. We assessed lacunes, microbleeds, white matter hyperintensity (WMH) and enlarged perivascular spaces (EPVS) on MRI and calculated the total cSVD burden.

RESULTS

A total of 297 subjects were included (median age: 65 years, male sex: 64.98%). In the adjusted model, when dividing TyG index into quartiles, subjects with TyG index in the top quartile, compared with those in the bottom quartile, were more likely to have lacunes (P = 0.035), moderate-severe WMH (P = 0.001), a higher grade of deep WMH (P = 0.004), a higher grade of PVWMH (P = 0.032), a higher grade of EPVS (P = 0.002), and a higher cSVD score (P < 0.001). When introducing TyG index into traditional risk factors to predict moderate to severe cSVD, both area under the curve (0.745 vs 0.802, P = 0.003) and integrated discrimination index (0.080, 95% CI 0.050-0.110, P < 0.001) displayed an improvement from TyG index.

CONCLUSIONS

The TyG index is correlated with cSVD and may have the potential to be a surrogate marker of insulin resistance and optimize the risk stratification.

Associations between triglyceride-glucose index and different hypertension subtypes: A population-based study in China

Background

Abnormal glycolipid metabolism plays a crucial role in hypertension. While an elevated triglyceride-glucose (TyG) index has been recognized as a risk factor for developing hypertension, the associations between the TyG index and different hypertension subtypes, namely, isolated systolic hypertension (ISH), isolated diastolic hypertension (IDH), and systolic-diastolic hypertension (SDH), remain unclear. This study was designed to investigate the associations between the TyG index and hypertension subtypes in a general Chinese population.

Materials and methods

In a sample of 16,793 participants from Shandong Province, China, multivariate logistic regression analyses were performed to examine the associations between the TyG index and different hypertension subtypes. Loess smooth curves were fitted to visualize the trends. Stratified analyses were conducted to further assess the potential interactions in the associations between the TyG index and different hypertension subtypes.

Results

A higher TyG index was associated with an increased odds of having IDH (OR = 2.94, 95% CI: 1.66–5.23) and SDH (OR = 1.82, 95% CI: 1.33–2.49), whereas no apparent relationship was observed between TyG index and ISH. With respect to sex, the effect of TyG index on having IDH and SDH was significant in women, but not in men. Participants with lower lipid profiles and glucose levels demonstrated a stronger strength of association between the TyG index and IDH as compared with the TyG index-SDH association. Stratified analysis showed that participants with a higher TyG index were more than 3 times more likely to have IDH and SDH among persons aged 18–42 years. Significant interactions were observed between TyG index and sex, age, and high-density lipoprotein cholesterol (HDL-C) in the SDH group, and a significant interaction was also found between TyG index and body mass index (BMI) in the ISH group.

Conclusion

Triglyceride-glucose index may potentially serve as a novel indicator for IDH and SDH. Our findings could also inform the development and implementation of targeted screening for hypertension.

Topical Reappraisal of Molecular Pharmacological Approaches to Endothelial Dysfunction in Diabetes Mellitus Angiopathy

Diabetes mellitus (DM) is a frequent medical problem, affecting more than 4% of the population in most countries. In the context of diabetes, the vascular endothelium can play a crucial pathophysiological role. If a healthy endothelium-which is a dynamic endocrine organ with autocrine and paracrine activity-regulates vascular tone and permeability and assures a proper balance between coagulation and fibrinolysis, and vasodilation and vasoconstriction, then, in contrast, a dysfunctional endothelium has received increasing attention as a potential contributor to the pathogenesis of vascular disease in diabetes. Hyperglycemia is indicated to be the major causative factor in the development of endothelial dysfunction. Furthermore, many shreds of evidence suggest that the progression of insulin resistance in type 2 diabetes is parallel to the advancement of endothelial dysfunction in atherosclerosis. To present the state-of-the-art data regarding endothelial dysfunction in diabetic micro- and macroangiopathy, we constructed this literature review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We interrogated five medical databases: Elsevier, PubMed, PMC, PEDro, and ISI Web of Science.

Nobiletin Protects Endothelial Cell Function via Upregulation of eNOS/ET-1 and Antioxidant Status-Related Genes under Nonstimulated and Inflammatory Conditions

Nobiletin, a natural polymethoxylated flavonoid compound, has been shown to exert a wide range of biological activities. However, there is limited evidence on the molecular mechanisms by which nobiletin modulates endothelial cell function. Our aim was to investigate the potential of nobiletin to enhance endothelial cell functionality under nonstimulated and inflammatory conditions. To this end, gene expression relevant to nitric oxide (NO) production, endothelin 1 (ET-1), and antioxidant status in human endothelial cells EA.hy926 was determined using real-time PCR. The fluorescence probe 4,5-diaminofluorescein (DAF-2) was used to measure NO production. The results demonstrated significant upregulation of eNOS and antioxidant genes as well as downregulation of ET-1 by nobiletin under nonstimulated and TNF-α-stimulated inflammatory conditions. These findings suggest a promising protective effect of nobiletin with relevance for cardiovascular health, likely through the NO/ET-1 dynamics and Nrf2 signaling pathway.

The molecular link between oxidative stress, insulin resistance, and type 2 diabetes: A target for new therapies against cardiovascular diseases

Type 2 Diabetes Mellitus (T2D) is a chronic disease with a pandemic incidence whose pathogenesis has not yet been clarified. Raising evidence highlighted the role of oxidative stress in inducing insulin resistance, pancreatic beta-cell dysfunction, and leading to cardiovascular disease (CVD). Therefore, understanding the link between oxidative stress, T2D and CVD may help to further understand the pathological processes beyond this association, to personalize the algorithm of the cure, and to find new therapeutic targets. Here, we discussed the role of oxidative stress and the decrease of antioxidant defenses in the pathogenesis of T2D. Furthermore, some aspects of hypoglycemic therapies and their potential role as antioxidant agents were examined, which might be pivotal in preventing CVD in T2D patients.

Relationship between Insulin Secretion and Arterial Stiffness in Essential Hypertension

The study aims to explore the relationship between plasma insulin secretion and arterial stiffness in nondiabetic essential hypertensive patients. A total of 730 nondiabetic essential hypertensive patients registered between January 2016 and October 2020 were enrolled. A two-hour oral glucose tolerance test (OGTT) was performed to detect the levels of C-peptide and blood glucose at 0 hours and 2 hours, as well as the difference between C-peptide (Δ C-peptide) and blood glucose (Δ blood glucose) over the same period. Patients were divided into two groups: the normal glucose tolerance (NGT) group (n = 322) and the impaired glucose tolerance (IGT) group (n = 408). A multiple linear regression analysis was used to evaluate the association between brachial-ankle pulse wave velocity (baPWV) and the other factors. 0 h C-peptide, 2 h C-peptide, and Δ C-peptide were found to be higher in the IGT group. baPWV was positively linear correlated with 2 h C-peptide (r = 0.086, p=0.020) and Δ C-peptide (r = 0.115, p=0.002). baPWV remained independently associated with 0 h C-peptide, 2 h C-peptide, and Δ C-peptide, after adjusting by age, gender, smoking, body mass index (BMI), high-density lipoprotein (HDL), cholesterol, systolic blood pressure (SBP), and triglycerides (TG). Our data shows that higher endogenous insulin secretion might play an important role in the progression of arterial stiffness in nondiabetic essential hypertensive patients.

Insulin resistance in ischemic stroke: Mechanisms and therapeutic approaches

The pathological condition of insulin resistance prevents the neuroprotective effects of insulin. Numerous studies have demonstrated that insulin resistance, as an independent risk factor for ischemic stroke, accelerates the formation of thrombosis and promotes the development of atherosclerosis, both of which are major mechanisms of ischemic stroke. Additionally, insulin resistance negatively affects the prognosis of patients with ischemic stroke regardless of whether the patient has diabetes, but the mechanisms are not well studied. We explored the association between insulin resistance and the primary mechanisms of brain injury in ischemic stroke (inflammation, oxidative stress, and neuronal damage), looking for potential causes of poor prognosis in patients with ischemic stroke due to insulin resistance. Furthermore, we summarize insulin resistance therapeutic approaches to propose new therapeutic directions for clinically improving prognosis in patients with ischemic stroke.

Triglyceride glucose index is associated with cerebral small vessel disease burden and cognitive impairment in elderly patients with type 2 diabetes mellitus

OBJECTIVE

To investigate the relations of Triglyceride glucose (TyG) index with cerebral small vessel disease (CSVD) burden and cognitive function in aged patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 308 elderly patients with T2DM were included in this retrospective study. The standardized Chinese version of Mini-Mental State Examination was used to assess cognitive function. The total CSVD burden score was assessed by combining four imaging markers of CSVD, including the presence of white matter hyperintensity, cerebral microbleeds in the deep, lacunes and enlarged perivascular spaces in the basal ganglia. The TyG index was calculated as the formula of ln [fasting triglyceride (mg/dl) × fasting plasma glucose (mg/dl)/2]. We used logistic regression analysis and mediation analysis to investigate the relations of TyG index with CSVD and cognitive function.

RESULTS

Multivariate binary logistic regression analysis showed that increased TyG index (OR: 2.241; 95% Confidence Interval(CI): 1.439 to 3.490; P <0.001), or severe CSVD burden (OR: 2.198; 95% CI: 1.283 to 3.763; P = 0.004) was associated with an increased risk of cognitive impairment in elderly patients with T2DM after adjusting for potential confounders. In addition, TyG index was an independent risk factor of severe CSVD burden (OR: 1.472; 95% CI: 1.003 to 2.160; P = 0.048) after controlling for potential confounders. Compared with the lowest TyG index tertile, the multivariable-adjusted OR of the highest tertile was 3.298 (95% CI: 1.685 to 6.452; P for trend <0.001) for cognitive impairment, 1.933 (95% CI: 1.010 to 3.698; P for trend = 0.047) for severe CSVD burden. Mediation analysis found a significant moderating effect of the severe CSVD burden on the association between higher TyG index levels and cognitive impairment.

CONCLUSIONS

The increased TyG index is an independent risk factor for cognitive impairment and severe CSVD burden in clinical practice. A proportion of the effect of increased TyG index on cognitive impairment may be due to the aggravation of CSVD burden.

Impact of Visit-to-Visit Triglyceride-Glucose Index Variability on the Risk of Cardiovascular Disease in the Elderly

BACKGROUND

The aging population is increasingly susceptible to cardiovascular disease (CVD). Visit-to-visit variability in glucose and lipid levels both contributed to CVD risk independent of their mean values. However, whether variability in the triglyceride-glucose (TyG) index is a risk factor for CVD remains unknown. Research Design and Methods. In this retrospective study of electronic health records, 27,520 participants aged over 60 years were enrolled. The visit-to-visit variability of TyG index was calculated from annual health examination data and defined as average real variability (ARV), standard deviation (SD), or the coefficient of variability (CV). CVD events were identified from the chronic disease registry or follow-up database and included myocardial infarction, angina, coronary, and stroke. Multivariate Cox regression was used to examine the correlation between TyG variability and incident CVD.

RESULTS

Over a median follow-up of 6.2 years, there were 2,178 CVD events. When participants were divided into four quartiles according to their TyG variability, after adjusting for established CVD risk factors, subjects in the top quartile had (HR = 1.18, 95% CI 1.05-1.34, P=0.005) significantly higher CVD risk than those in the bottom quartile. The association remained significant in overweight individuals or those without diabetes (P < 0.005 and P < 0.01, respectively).

CONCLUSIONS

High variability in TyG was significantly associated with elevated CVD risk in the elderly, independent of average TyG and other risk factors. Close monitoring variability in TyG might be informative to identify old individuals at high risk of CVD.

Salt-Sensitivity of Blood Pressure and Insulin Resistance

Salt sensitivity of blood pressure (SSBP) is an independent risk factor for cardiovascular morbidity and mortality that is seen in both hypertensive and normotensive populations. Insulin resistance (IR) strongly correlates with SSBP and affects nearly 50% of salt sensitive people. While the precise mechanism by which IR and SSBP relate remains elusive, several common pathways are involved in the genesis of both processes, including vascular dysfunction and immune activation. Vascular dysfunction associated with insulin resistance is characterized by loss of nitric oxide (NO)-mediated vasodilation and heightened endothelin-1 induced vasoconstriction, as well as capillary rarefaction. It manifests with increased blood pressure (BP) in salt sensitive murine models. Another common denominator in the pathogenesis of insulin resistance, hypertension, and salt sensitivity (SS) is immune activation involving pro-inflammatory cytokines like tumor necrosis factor (TNF)-α, IL-1β, and IL-6. In the last decade, a new understanding of interstitial sodium storage in tissues such as skin and muscle has revolutionized traditional concepts of body sodium handling and pathogenesis of SS. We have shown that interstitial Na⁺ can trigger a T cell mediated inflammatory response through formation of isolevuglandin protein adducts in antigen presenting cells (APCs), and that this response is implicated in salt sensitive hypertension. The peroxisome proliferator-activated receptor γ (PPARγ) is a transcription factor that modulates both insulin sensitivity and BP. PPARγ agonists increase insulin sensitivity and ameliorate salt sensitivity, whereas deficiency of PPARγ results in severe insulin resistance and hypertension. These findings suggest that PPARγ plays a role in the common pathogenesis of insulin sensitivity and salt sensitivity, perhaps via effects on the immune system and vascular function. The goal of this review is to discuss those mechanisms that may play a role in both SSBP and in insulin resistance.

Systems biology of angiogenesis signaling: Computational models and omics

Angiogenesis is a highly regulated multiscale process that involves a plethora of cells, their cellular signal transduction, activation, proliferation, differentiation, as well as their intercellular communication. The coordinated execution and integration of such complex signaling programs is critical for physiological angiogenesis to take place in normal growth, development, exercise, and wound healing, while its dysregulation is critically linked to many major human diseases such as cancer, cardiovascular diseases, and ocular disorders; it is also crucial in regenerative medicine. Although huge efforts have been devoted to drug development for these diseases by investigation of angiogenesis‐targeted therapies, only a few therapeutics and targets have proved effective in humans due to the innate multiscale complexity and nonlinearity in the process of angiogenic signaling. As a promising approach that can help better address this challenge, systems biology modeling allows the integration of knowledge across studies and scales and provides a powerful means to mechanistically elucidate and connect the individual molecular and cellular signaling components that function in concert to regulate angiogenesis. In this review, we summarize and discuss how systems biology modeling studies, at the pathway‐, cell‐, tissue‐, and whole body‐levels, have advanced our understanding of signaling in angiogenesis and thereby delivered new translational insights for human diseases.

This article is categorized under:

Cardiovascular Diseases > Computational Models

Cancer > Computational Models

Hyperuricemia-induced endothelial insulin resistance: the nitric oxide connection

Hyperuricemia, defined as elevated serum concentrations of uric acid (UA) above 416 µmol L^-1, is related to the development of cardiometabolic disorders, probably via induction of endothelial dysfunction. Hyperuricemia causes endothelial dysfunction via induction of cell apoptosis, oxidative stress, and inflammation; however, it's interfering with insulin signaling and decreased endothelial nitric oxide (NO) availability, resulting in the development of endothelial insulin resistance, which seems to be a major underlying mechanism for hyperuricemia-induced endothelial dysfunction. Here, we elaborate on how hyperuricemia induces endothelial insulin resistance through the disruption of insulin-stimulated endothelial NO synthesis. High UA concentrations decrease insulin-induced NO synthesis within the endothelial cells by interfering with insulin signaling at either the receptor or post-receptor levels (i.e., proximal and distal steps). At the proximal post-receptor level, UA impairs the function of the insulin receptor substrate (IRS) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) in the insulin signaling pathway. At the distal level, high UA concentrations impair endothelial NO synthase (eNOS)-NO system by decreasing eNOS expression and activity as well as by direct inactivation of NO. Clinically, UA-induced endothelial insulin resistance is translated into impaired endothelial function, impaired NO-dependent vasodilation, and the development of systemic insulin resistance. UA-lowering drugs may improve endothelial function in subjects with hyperuricemia.

Insulin resistance, cardiovascular stiffening and cardiovascular disease

The cardiometabolic syndrome (CMS) and obesity are typically characterized by a state of metabolic insulin resistance. As global and US rates of obesity increase there is an acceleration of the incidence and prevalence of insulin resistance along with associated cardiovascular disease (CVD). Under physiological conditions insulin regulates glucose homeostasis by enhancing glucose disposal in insulin sensitive tissues while also regulating delivery of nutrients through its vasodilation actions on small feed arteries. Specifically, insulin-mediated production of nitric oxide (NO) from the vascular endothelium leads to increased blood flow enhancing disposal of glucose. Typically, insulin resistance is considered as a decrease in sensitivity or responsiveness to the metabolic actions of insulin including insulin-mediated glucose disposal. However, a decreased sensitivity to the normal vascular actions of insulin, especially diminished nitric oxide production, plays an additional important role in the development of CVD in states of insulin resistance. One mechanism by which insulin resistance and attendant hyperinsulinemia promote CVD is via increases in vascular stiffness. Although obesity and insulin resistance are known to be associated with substantial increases in the prevalence of vascular fibrosis and stiffness the mechanisms and mediators that underlie vascular stiffening in insulin resistant states are complex and have only recently begun to be addressed. Current evidence supports the role of increased plasma levels of aldosterone and insulin and attendant reductions in bioavailable NO in the pathogenesis of impaired vascular relaxation and vascular stiffness in the CMS and obesity. Aldosterone and insulin both increase the activity of serum and glucocorticoid kinase 1 (SGK-1) which in turn is a major regulator of vascular and renal sodium (Na⁺⁾ channel activity.The importance of SGK-1 in the pathogenesis of the CMS is highlighted by observations that gain of function mutations in SGK-1 in humans promotes hypertension, insulin resistance and obesity. In endothelial cells, an increase in Na⁺ flux contributes to remodeling of the cytoskeleton, reduced NO bioavailability and vascular stiffening. Thus, endothelial SGK-1 may represent a point of convergence for insulin and aldosterone signaling in arterial stiffness associated with obesity and the CMS. This review examines our contemporary understanding of the link between insulin resistance and increased vascular stiffness with emphasis placed on a role for enhanced SGK-1 signaling as a key node in this pathological process.

Increased insulin resistance is associated with vascular cognitive impairment in Chinese patients with cerebral small vessel disease

BACKGROUND

The aim of this study was to investigate the association between insulin resistance (IR) and vascular cognitive impairment (VCI) in patients with cerebral small vessel disease (CSVD).

METHODS

A total of 275 CSVD patients were enrolled in this retrospective case-control study. The homeostatic model assessment of insulin resistance (HOMA-IR) was used to measure the index of insulin resistance. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA). Spearman's correlation coefficient was used to evaluate the correlation between HOMA-IR and MoCA score. The variance inflation factor (VIF) was used to detect collinearity between variables. Multivariate logistic regression analysis was employed to confirm whether HOMA-IR is an independent risk factor for VCI in CVSD. Finally, receiver operating characteristic (ROC) curve analysis was conducted to assess the diagnostic value of HOMA-IR in VCI.

RESULTS

Of the 275 patients, 164 displayed VCI. VCI patients showed a significantly higher level of HOMA-IR compared to non-VCI patients (P < 0.001). HOMA-IR was negatively correlated with the MoCA score (r = -0.593, P < 0.001). After adjusting for potential confounding variables, using HOMA-IR quartile 1 (<1.11) as the reference, HOMA-IR quartile 3 (1.71-2.50) and quartile 4 (≥2.50) were independently associated with the occurrence of VCI; for each one unit increase in the HOMA-IR, the risk of VCI increased by 177.3% (odds ratio 2.773, 95% confidence interval: 1.050-7.324, P = 0.040) and 444.3% (odds ratio 5.443, 95% confidence interval: 2.109-14.050, P < 0.001), respectively. According to the ROC curve, the optimal cut-off point of HOMA-IR in predicting VCI was 1.55, and the area under the curve was 0.744, with a sensitivity of 71.3% and a specificity of 69.4%.

CONCLUSION

This study demonstrated that increased IR is significantly associated with VCI in CSVD patients.

Endothelium-dependent remote signaling in ischemia and reperfusion: Alterations in the cardiometabolic continuum

Intact endothelial function plays a fundamental role for the maintenance of cardiovascular (CV) health. The endothelium is also involved in remote signaling pathway-mediated protection against ischemia/reperfusion (I/R) injury. However, the transfer of these protective signals into clinical practice has been hampered by the complex metabolic alterations frequently observed in the cardiometabolic continuum, which affect redox balance and inflammatory pathways. Despite recent advances in determining the distinct roles of hyperglycemia, insulin resistance (InR), hyperinsulinemia, and ultimately diabetes mellitus (DM), which define the cardiometabolic continuum, our understanding of how these conditions modulate endothelial signaling remains challenging. It is widely accepted that endothelial cells (ECs) undergo functional changes within the cardiometabolic continuum. Beyond vascular tone and platelet-endothelium interaction, endothelial dysfunction may have profound negative effects on outcome during I/R. In this review, we summarize the current knowledge of the influence of hyperglycemia, InR, hyperinsulinemia, and DM on endothelial function and redox balance, their influence on remote protective signaling pathways, and their impact on potential therapeutic strategies to optimize protective heterocellular signaling.

Impact of Hyperinsulinemia on Long-Term Clinical Outcomes of Percutaneous Coronary Intervention in Patients without Diabetes Who Have Acute Myocardial Syndrome

BACKGROUND AND OBJECTIVES

Hyperinsulinemia plays a key role in the development of cardiovascular impairment in patients with metabolic syndrome. The aim of this study was to evaluate the influence of hyperinsulinemia on long-term clinical outcomes of percutaneous coronary intervention (PCI) in patients without diabetes mellitus who have acute myocardial syndrome (ACS).

METHODS

Between March 2016 and January 2019, we enrolled 468 patients with ACS and without diabetes mellitus who received primary PCI. Patients were divided into a low-insulin group (n = 157), medium-insulin group (n = 154), and high-insulin group (n = 157) according to tertiles of fasting insulin level. The primary endpoint was major adverse cardiac events (MACE; all-cause death, non-fatal myocardial infarction, target vessel revascularization [TVR]) at 24 months. The secondary endpoint was angina hospitalization.

RESULTS

Patients in the high-insulin group had an unfavorable prognosis, with a higher rate of MACE (34.39%) than the low-insulin group (22.29%) and medium-insulin group (23.37%) at 24 months (P < 0.05). This difference was mainly driven by the increase in TVR. The high-insulin group also had a higher rate of angina hospitalization than the low-insulin group. Cox proportional hazards regression showed that high-insulin level (hazard ratio [HR] 1.870, 95% confidence interval [CI] 1.202-2.909), small-vessel lesion (HR 1.713, 95% CI 1.111-2.642), bifurcation lesion (HR 3.394, 95% CI 2.033-5.067), SYNTAX score (HR 1.084, 95% CI 1.039-1.130), and stent length (HR 1.017, 95% CI 1.002-1.032) increased the incidence of MACE in patients with ACS and without diabetes who underwent PCI.

CONCLUSION

Hyperinsulinemia might be a valid predictor of clinical outcomes in patients with ACS undergoing PCI.