Efficacy of dulaglutide on vascular health indexes in subjects with type 2 diabetes: a randomized trial

Therapeutic strategies targeting mechanisms of macrophages in diabetic heart disease

Diabetic heart disease (DHD) is a serious complication in patients with diabetes. Despite numerous studies on the pathogenic mechanisms and therapeutic targets of DHD, effective means of prevention and treatment are still lacking. The pathogenic mechanisms of DHD include cardiac inflammation, insulin resistance, myocardial fibrosis, and oxidative stress. Macrophages, the primary cells of the human innate immune system, contribute significantly to these pathological processes, playing an important role in human disease and health. Therefore, drugs targeting macrophages hold great promise for the treatment of DHD. In this review, we examine how macrophages contribute to the development of DHD and which drugs could potentially be used to target macrophages in the treatment of DHD.

Separate and combined effects of empagliflozin and semaglutide on vascular function: A 32-week randomized trial

AIM

Despite the increasing use of combination treatment with sodium-glucose cotransporter 2 inhibitors and glucagon-like peptide-1 receptor agonists, data are limited on the effects of combination treatment on markers of cardiovascular disease. This study aimed to investigate the effect of empagliflozin, semaglutide, and their combination on vascular function.

MATERIALS AND METHODS

In total, 120 patients with type 2 diabetes were randomized into four groups (n = 30 in each) for 32 weeks: placebo, semaglutide, empagliflozin, and their combination. The study had two co-primary outcomes: change in arterial stiffness and kidney oxygenation. This paper reports on arterial stiffness assessed as carotid-femoral pulse wave velocity. Secondary outcomes included 24-h blood pressure (BP), 24-h central BP, urinary albumin to creatinine ratio and glycaemic control assessed by both continuous glucose monitoring and glycated haemoglobin.

RESULTS

The carotid-femoral pulse wave velocity did not change significantly in any of the groups compared with placebo. Twenty-four-hour systolic BP was reduced by 10 mmHg (95% CI 6-14), p < .001 in the combination group, significantly superior to both placebo and monotherapy (p < .05). Combination treatment increased glycaemic time in range from 72% at baseline to 91% at week 32, p < .001, without increasing time below range. The urinary albumin to creatinine ratio decreased by 36% (95% CI 4-57), p = .03 in the combination group compared with placebo.

CONCLUSIONS

Empagliflozin, semaglutide, or their combination did not reduce arterial stiffness. Combination treatment showed a substantial and clinically important reduction in 24-h systolic BP compared with either treatment alone. Combination treatment increased glycaemic time in range without increasing the risk of hypoglycaemia.

Dulaglutide restores endothelial progenitor cell levels in diabetic mice and mitigates high glucose-induced endothelial injury through SIRT1-mediated mitochondrial fission

Type 2 diabetes mellitus (T2DM) significantly impairs the functionality and number of endothelial progenitor cells (EPCs) and resident endothelial cells, critical for vascular repair and regeneration, exacerbating the risk of vascular complications. GLP-1 receptor agonists, like dulaglutide, have emerged as promising therapeutic agents due to their multifaceted effects, including the enhancement of EPC activity and protection of endothelial cells. This study investigates dulaglutide's effects on peripheral blood levels of CD34+ and CD133+ cells in a mouse model of lower limb ischemia and its protective mechanisms against high-glucose-induced damage in endothelial cells. Results demonstrated that dulaglutide significantly improves blood flow, reduces tissue damage and inflammation in ischemic limbs, and enhances glycemic control. Furthermore, dulaglutide alleviated high-glucose-induced endothelial cell damage, evident from improved tube formation, reduced reactive oxygen species accumulation, and restored endothelial junction integrity. Mechanistically, dulaglutide mitigated mitochondrial fission in endothelial cells under high-glucose conditions, partly through maintaining SIRT1 expression, which is crucial for mitochondrial dynamics. This study reveals the potential of dulaglutide as a therapeutic option for vascular complications in T2DM patients, highlighting its role in improving endothelial function and mitochondrial integrity.

The effect of subcutaneous dulaglutide on weight loss in patients with Type 2 diabetes mellitus: Systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Dulaglutide, a subcutaneously administered glucagon-like peptide 1 receptor agonist, has been hypothesized to lead to weight loss in patients with Type 2 diabetes mellitus (T2DM). However, the consequences of its prescription on body weight (BW) and other anthropometric indices, for example, body mass index (BMI) or waist circumference (WC), have not been completely clarified. Therefore, we aimed to assess the effects of subcutaneous dulaglutide administration on BW, BMI and WC values in T2DM subjects by means of a systematic review and meta-analysis of RCTs.

METHODS

We computed a literature search in five databases (PubMed/Medline, Web of Science, EMBASE, Scopus and Google Scholar) from their inception to February 2023 to identify RCTs that examined the influence of subcutaneous dulaglutide on obesity indices. We calculated effect sizes using the random-effects model (using DerSimonian-Laird method). Results were derived across weighted mean differences (WMD) and 95% confidence intervals (CI). Subgroup analyses were applied to explore possible sources of heterogeneity among the RCTs. The current systematic review and meta-analysis was conducted in compliance with The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

RESULTS

In total, 18 studies with 33 RCT arms (BW = 33 RCT arms, 14,612 participants, 7869 cases and 6743 controls; BMI = 10 RCT arms, 14,612 subjects, 7869 cases and 6743 controls; WC = 10 RCT arms, 1632 participants, 945 cases and 687 cases) were included in the meta-analysis. BW (WMD: -0.86 kg, 95% CI: -1.22, -0.49, p < 0.001), BMI (WMD: -0.68 kg/m2 , 95% CI: -0.88, -0.49, p < 0.001) and WC (WMD: -1.23 cm, 95% CI: -1.82, -0.63, p < 0.001) values decreased notably following subcutaneous dulaglutide administration versus placebo. BW notably decreased in RCTs lasting >18 weeks (WMD: -1.42 kg, 95% CI: -1.90, -0.94, p < 0.001), whereas notable reductions in WC were seen in RCTs lasting ≤18 weeks (WMD: -1.78 cm, 95% CI: -2.59, -0.98, p < 0.001). Dulaglutide dosages >1 mg/day significantly decreased BW (WMD: -1.94 kg, 95% CI: -2.54, -1.34, p < 0.001), BMI (WMD: -0.80 kg/m2 , 95% CI: -1.07, -0.54, p < 0.001) and WC (WMD: -1.47 cm, 95% CI: -1.80, -1.13, p < 0.001). BW decreased particularly following dulaglutide prescription in individuals with obesity (WMD: -1.05 kg, 95% CI: -1.28, -0.82, p < 0.001) versus overweight. The dose-response meta-analysis revealed that BW decreased significantly when dulaglutide was prescribed in doses ≤3 mg/day versus >3 mg/day.

CONCLUSIONS

Subcutaneous dulaglutide administration in T2DM reduces BW, BMI and WC. The decrease in BW and WC was influenced by the dose and the duration of dulaglutide administration. The reduction in BMI was only influenced by the dosage of dulaglutide. Moreover, T2DM patients who suffered from obesity experienced a notable decrease in BW versus T2DM subjects without obesity.

Comparative effects of fixed-dose mitiglinide/voglibose combination and glimepiride on vascular endothelial function and glycemic variability in patients with type 2 diabetes: A randomized controlled trial

INTRODUCTION

The aim of this study was to compare the effects of mitiglinide/voglibose with those of glimepiride on glycemic variability and vascular endothelial function in patients with type 2 diabetes.

MATERIALS AND METHODS

It was a multicenter, open-label, randomized, crossover study. Hospitalized patients received either mitiglinide/voglibose (three times daily administration of 10 mg mitiglinide and 0.2 mg voglibose) or glimepiride (once-daily 2 mg) in random order, each for 5 days. The reactive hyperemia index (RHI) and the mean amplitude of glycemic excursions (MAGE) were measured as co-primary endpoints using reactive hyperemia peripheral arterial tonometry and continuous glucose monitoring.

RESULTS

The analysis included 30 patients (15 in each group). The RHI was 1.670 ± 0.369 during treatment with mitiglinide/voglibose and 1.716 ± 0.492 during treatment with glimepiride, with no significant difference between the two. MAGE was significantly lower in the mitiglinide/voglibose group (47.6 ± 18.5 mg/dL) than in the glimepiride group (100.6 ± 32.2 mg/dL). Although the mean blood glucose levels over the entire 24 h period were comparable between the two groups, the use of mitiglinide/voglibose was associated with a lower standard deviation of mean glucose, coefficient of variation, and mean postprandial glucose excursion compared with glimepiride. The time below range (<70 mg/dL) and the time above range (>180, >200, and 250 mg/dL) were lower in the mitiglinide/voglibose group, while the time in range (70-180 mg/dL) was higher.

CONCLUSIONS

In our short-duration randomized crossover study, although not impacting vascular endothelial function, mitiglinide/voglibose demonstrated potential benefits in reducing glycemic variability, postprandial hyperglycemia, and hypoglycemia in patients with type 2 diabetes.

Discovery of new α-glucosides, antiglycation agent, and in silico study of 2-(3,4-dihydroxyphenyl)-7,8-dihydroxy-3-methoxy-4H-chromen-4-one isolated from Pistacia chinensis

Pistacia chinensis is locally practiced for treating diabetes, pain, inflammation, and erectile dysfunction. Therefore, the current studies subjected the crude extract/fractions and the isolated compound (2-(3,4-dihydroxyphenyl)-7,8-dihydroxy-3-methoxy-4H-chromen-4-one) to α-glucosidase inhibitor and anti-glycation activities. The development of long-term complications associated with diabetes is primarily caused by chronic hyperglycemia. Regarding α-glucosidase, the most significant inhibitory effect was observed with compound 1 (93.09%), followed by the methanolic extract (80.87%) with IC50 values of 45.86 and 86.32 μM. The maximum anti-glycation potential was shown by an isolated compound 1 followed by methanolic extract with effect inhibition of 90.12 and 72.09, respectively. Compound 1 is expected to have the highest gastrointestinal absorption rate, with a predicted absorption rate of 86.156%. This indicates oral suitability. The compound 1 is expected to have no harmful effects on the liver. In addition, our docking results suggest that alpha-glucosidase and isolated compounds showed strong interaction with ILE821, GLN900, and ALA901 residues, along with a -11.95 docking score.

Predictors of microvascular complications in patients with type 2 diabetes mellitus at regional referral hospitals in the central zone, Tanzania: a cross-sectional study

Microvascular complications encompass a group of diseases which result from long-standing chronic effect of diabetes mellitus (DM). We aimed to determine the prevalence of microvascular complications and associated risk factors among patients with type 2 diabetes mellitus (T2DM). A cross-sectional analytical hospital-based study was conducted at Singida and Dodoma regional referral hospitals in Tanzania from December 2021 to September 2022. A total of 422 patients with T2DM were included in the analysis by determining the prevalence of microvascular complications and their predictors using multivariable logistic regression analysis. A two-tailed p value less than 0.05 was considered statistically significant. The prevalence of microvascular complications was 57.6% (n = 243) and diabetic retinopathy was the most common microvascular complication which accounted for 21.1% (n = 89). Having irregular physical activity (AOR = 7.27, 95% CI = 2.98-17.71, p < 0.001), never having physical activity (AOR = 2.38, 95% CI = 1.4-4.01, p = 0.013), being hypertensive (AOR = 5.0, 95% CI = 2.14-11.68, p = 0.030), having T2DM for more than 5 years (AOR = 2.74, 95% CI = 1.42-5.26, p = 0.025), being obese (AOR = 2.63, 95% CI = 1.22-5.68, p = 0.010), and taking anti-diabetic drugs irregularly (AOR = 1.94, 95% CI = 0.15-0.77, p < 0.001) were the predictors of microvascular complications. This study has revealed a significant proportion of microvascular complications in a cohort of patients with T2DM. Lack of regular physical activity, being obese, taking anti-diabetic drugs irregularly, presence of hypertension, and long-standing duration of the disease, were significantly associated with microvascular complications.

Association of Hematological Parameters and Diabetic Neuropathy: A Retrospective Study

Background

Diabetic neuropathy (DN) is a common complication of type 2 diabetes (T2DM) and is characterized by persistent inflammation. Hematological parameters have emerged as a novel marker for detecting chronic inflammatory conditions, including diabetes.

Aim

We aim to examine the association between HbA1c levels, which can indicate the presence of diabetic neuropathy, and hematological parameters to explore the possibility of using hematological parameters as a new indicator for DN in T2DM patients.

Methods

This was a retrospective study of 768 (483 males and 284 females) medical records of adult T2DM patients with or without neuropathy who attending the outpatient neuromuscular clinic at King Abdul-Aziz University Hospital from January 2016 to December 2021.

Results

The results showed significant increases in HbA1c levels (p=0.000), lymphocyte levels (p=0.028), and the neutrophil-lymphocyte ratio (NLR) (p=0.011). In the T2DM group, HBA1C levels were found to be positively correlated with age (r=0.306, p=0.000), neutrophil (NEUT) (r=0. 287, p=0.000), platelet (PLT) (r=0. 148, p=0.039), and neutrophil-lymphocyte ratio (NLR) (r=0.306193, p=0.0007), and negatively correlated with gender (r=-0.306193, p=0.0007). In the T2DMN group, HBA1C levels showed a positive correlation with hemoglobin (HB) (r=0.084, p=0.045), PLT (r=0.087, p=0.037), and PLT/mean corpuscular hemoglobin (MCH) ratio (PLT/MCH ratio) (r=0.12, p=0.004), and a negative correlation with age (r=-0.204, p=0.000), gender (r=-0.086, p=0.041), weight (WT) (r=-0.113, p=0.007), Body Surface Area (BSA) (r=-0.09, p=0.031), mean corpuscular volume (MCV) (r=-0.292, p=0.000), and MCH (r=-0.186, p=0.000).

Conclusion

Our study found a significant association between HbA1c, a biomarker for diabetic neuropathy, and various hematological parameters (HB, MCV, MCH, PLT, PLT/MCH ratio) in T2DMN patients. By effectively controlling and monitoring these variables, it may be feasible to prevent or delay the progression of peripheral neuropathy in diabetic patients. However, further research is needed to validate these findings.

The glycosylated hemoglobin level and the severity of cardiovascular involvement in patients with the first episode of acute coronary syndrome

Background

The current study was carried out aiming at investigating the relationship between glycosylated hemoglobin level and coronary atherosclerosis in patients with the first episode of acute coronary syndrome.

Methods

This case-control study evaluated 450 patients with the first episode of acute coronary syndrome in Ayatollah Rouhani Hospital in Babol (Iran) from 2011 to 2018. Based on glycosylated hemoglobin, patients were divided into three groups of non-diabetic, pre-diabetic, and diabetic (n=150 in each group). Since SYNTAX score and Gensini score are employed to evaluate the extent of cardiovascular disease and predict CVD in patients with CAD over long-term follow-up, we calculated SYNTAX score and Gensini score based on angiographic results.

Results

Concerning the factors related to the severity of cardiovascular involvement, the results revealed no significant difference between the diabetic and pre-diabetic groups in terms of the frequency of patients in terms of SYNTAX score, Gensini score, and the number of vessels involved (0.142 and 87, respectively, and P=0.102). However, this difference between the diabetic and non-diabetic groups, as well as between the pre-diabetic and non-diabetic groups was statistically significant (respectively for SYNTAX score, p< 0.001 and P=0.001; for Gensini score, P=0.013 and P=0.019; and for the number of vessels involved P=0.001and p<0.001).

Conclusion

According to the findings of the current study, since there was no significant difference between diabetic and pre-diabetic patients in terms of the components indicating the severity of cardiovascular involvement, pre-diabetes itself may be associated with the severity of cardiovascular involvement as a predisposing factor.

Exosomes and their derivatives as biomarkers and therapeutic delivery agents for cardiovascular diseases: Situations and challenges

Microvesicles known as exosomes have a diameter of 40 to 160 nm and are derived from small endosomal membranes. Exosomes have attracted increasing attention over the past ten years in part because they are functional vehicles that can deliver a variety of lipids, proteins, and nucleic acids to the target cells they encounter. Because of this function, exosomes may be used for the diagnosis, prognosis and treatment of many diseases. All throughout the world, cardiovascular diseases (CVDs) continue to be a significant cause of death. Because exosomes are mediators of communication between cells, which contribute to many physiological and pathological aspects, they may aid in improving CVD therapies as biomarkers for diagnosing and predicting CVDs. Many studies demonstrated that exosomes are associated with CVDs, such as coronary artery disease, heart failure, cardiomyopathy and atrial fibrillation. Exosomes participate in the progression or inhibition of these diseases mainly through the contents they deliver. However, the application of exosomes in diferent CVDs is not very mature. So further research is needed in this field.

Effects of first-line antidiabetic drugs on the improvement of arterial stiffness: A Bayesian network meta-analysis

BACKGROUND

Changes in vascular function are closely associated with the development of cardiovascular disease (CVD). Pulse wave velocity (PWV) is a potential indicator of vascular dysfunction; it allows noninvasive assessment of arterial stiffness. Currently, evidence for the effects of different classes of antidiabetic drugs on arterial stiffness remains limited. In this study, a network meta-analysis (NMA) was performed to explore the associations between changes in arterial stiffness and first-line antidiabetic drugs by evaluating PWV in patients with different metabolic abnormalities.

METHODS

We systematically searched several electronic databases for randomized controlled trials (RCTs) published from inception until 25 August 2022, without language restrictions. The primary outcome was the change in PWV (ΔPWV) in all included studies; subgroup analysis was performed for patients with abnormal glucose metabolism, including prediabetes and diabetes mellitus. NMA was performed to calculate the mean differences (MDs) with 95% confidence intervals (CIs) as effect sizes to evaluate the ΔPWV.

RESULTS

Among the 2257 candidate articles identified in the initial search, 18 RCTs were eventually included in the analysis. In all studies, two classes of new antidiabetic drugs, glucagon-like peptide-1 receptor (GLP-1R) agonists and sSodium-glucose co-transporter 2 (SGLT-2) inhibitors, improved arterial stiffness by decreasing PWV compared with placebo (MD = -1.11, 95% CI: -1.94 to 0.28) and (MD = -0.76, 95% CI: -1.45 to -0.08). A conventional antidiabetic drug, metformin, also showed similar efficacy compared with placebo (MD = -0.73, 95% CI: -1.33 to -0.12). Finally, in subgroup studies of patients with abnormal glucose metabolism diseases, GLP-1R agonists (MD = -1.06, 95% CI: -2.05 to -0.10) significantly decreased PWV compared with placebo.

CONCLUSION

Three classes of antidiabetic drugs-GLP-1R agonists, SGLT-2 inhibitors, and metformin-have the potential to improve arterial stiffness. Among the six classes of antidiabetic drugs analyzed, GLP-1R agonists constitute the only class of drugs that improves arterial stiffness in patients with abnormal glucose metabolism diseases.

Detection, management, and prevention of diabetes-related foot disease in the Australian context

Diabetes-related foot disease (DFD) is a widely feared complication among people who live with diabetes. In Australia and globally, rates of disability, cardio-vascular disease, lower extremity amputation, and mortality are significantly increased in patients with DFD. In order to understand and prevent these outcomes, we analyse the common pathogenetic processes of neuropathy, arterial disease, and infection. The review then summarises important management considerations through the interdisciplinary lens. Using Australian and international guidelines, we offer a stepwise, evidence-based practical approach to the care of patients with DFD.

Potential molecular mechanism underlying cardiac fibrosis in diabetes mellitus: a narrative review

BACKGROUND

Diabetes mellitus (DM) is among the most common risk factors for cardiovascular disease in the world with prevalence of more than 500 million population in 2021. Cardiac fibrosis with its complex process has been hypothesized as one of the mechanisms explaining development of heart failure in diabetic patients. Recently, the biomolecular mechanism of cardiac fibrosis in the hyperglycemia setting has been focusing around transforming growth factor β-1 (TGFβ-1) as a major factor. However, there is interplay role of several factors including microRNAs (miRNAs) which acts as a potential regulator of cardiac fibrosis connected with TGFβ-1. In this review, we explored interplay role of several factors including microRNAs which acts as a potential regulator of cardiac fibrosis connected with TGFβ-1 in diabetes mellitus. This narrative review included articles from the PubMed and Science Direct databases published in the last 10 years (2012-2022).

MAIN TEXT

In diabetic patients, excessive activation of myofibroblasts occurs and triggers pro-collagen to convert into mature collagen to fill the cardiac interstitial space resulting in a pathological process of extracellular matrix remodeling. The balance between matrix metalloproteinase (MMP) and its inhibitor (tissue inhibitor of metalloproteinase, TIMP) is crucial in degradation of the extracellular matrix. Diabetes-related cardiac fibrosis is modulated by increasing level of TGF-β1 mediated by cellular components, including cardiomyocyte and non-cardiomyocyte cells involving fibroblasts, vascular pericytes smooth muscle cells, endothelial cells, mast cells, macrophages, and dendritic cells. Several miRNAs such as miR-21, miR-9, miR-29, miR-30d, miR-144, miR-34a, miR-150, miR-320, and miR-378 are upregulated in diabetic cardiomyopathy. TGF-β1, together with inflammatory cytokines, oxidative stress, combined sma and the mothers against decapentaplegic (smad) protein, mitogen-activated protein kinase (MAPK), and microRNAs, is interconnectedly involved in extracellular matrix production and fibrotic response. In this review, we explored interplay role of several factors including microRNAs which acts as a potential regulator of cardiac fibrosis connected with TGFβ-1 in diabetes mellitus.

CONCLUSIONS

Long-term hyperglycemia activates cardiac fibroblast via complex processes involving TGF-β1, miRNA, inflammatory chemokines, oxidative stress, smad, or MAPK pathways. There is increasing evidence of miRNA's roles lately in modulating cardiac fibrosis.

Real-World Efficacy of Glucagon-like Peptide-1 (GLP-1) Receptor Agonist, Dulaglutide, on Metabolic Parameters in Japanese Patients with Type 2 Diabetes: A Retrospective Longitudinal Study

The glucagon-like peptide-1 receptor agonist (GLP-1RA) dulaglutide has been shown to improve body weight and glycemic control and reduce major cardiovascular (CV) events. In Japan, dulaglutide is used at a fixed dose of 0.75 mg, which is lower than that in Europe and North America. However, the reports of real-world efficacy on metabolic parameters in Japanese patients with type 2 diabetes (T2DM) are limited. This study aimed to examine the real-world efficacy of GLP-1RA dulaglutide on metabolic parameters in Japanese patients with T2DM. We retrospectively selected patients with T2DM who had been prescribed dulaglutide continuously for 12 months or longer between September 2015 and December 2020 and compared metabolic parameters at baseline with the data at 12 months after the start of dulaglutide. One hundred twenty-one patients were enrolled in this study. The 12-month dulaglutide treatment reduced body weight by 1.7 kg and hemoglobin A1c by 1.1%. Significant improvements were also observed in serum high-density lipoprotein cholesterol (HDL-C), triglyceride (TG) and non-HDL-C. The change in HbA1c during dulaglutide treatment was significantly correlated with the changes in HDL-C (R = −0.236, p = 0.013), LDL-C (R = 0.377, p = 0.005) and non-HDL-C (R = 0.415, p < 0.001). The improvements in HbA1c, HDL-C, TG and non-HDL-C were greater in patients concurrently treated with SGLT2 inhibitors (SGLT2is) at baseline. In conclusion, the treatment with dulaglutide has beneficial effects on multiple CV risk factors in Japanese patients with T2DM.

Weight-dependent and weight-independent effects of dulaglutide on blood pressure in patients with type 2 diabetes

BACKGROUND

Patients with type 2 diabetes (T2D) treated with glucagon-like peptide-1 receptor agonists may experience reductions in weight and blood pressure. The primary objective of the current study was to determine the weight-dependent and weight-independent effects of ~ 6 months treatment with dulaglutide 1.5 mg treatment in participants with T2D.

METHODS

Mediation analysis was conducted for five randomized, placebo-controlled trials of dulaglutide 1.5 mg to estimate the weight-dependent (i.e., mediated by weight) and weight-independent effects from dulaglutide vs. placebo on change from baseline for systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure. A random-effects meta-analysis combined these results. To investigate a dose response between dulaglutide 4.5 mg and placebo, mediation analysis was first conducted in AWARD-11 to estimate the weight-dependent and weight-independent effects of dulaglutide 4.5 mg vs. 1.5 mg, followed by an indirect comparison with the mediation result for dulaglutide 1.5 mg vs. placebo.

RESULTS

Baseline characteristics were largely similar across the trials. In the mediation meta-analysis of placebo-controlled trials, the total treatment effect of dulaglutide 1.5 mg after placebo-adjustment on SBP was - 2.6 mmHg (95% CI - 3.8, - 1.5; p < 0.001) and was attributed to both a weight-dependent effect (- 0.9 mmHg; 95% CI: - 1.4, - 0.5; p < 0.001) and a weight-independent effect (- 1.5 mmHg; 95% CI: - 2.6, - 0.3; p = 0.01), accounting for 36% and 64% of the total effect, respectively. For pulse pressure, the total treatment effect of dulaglutide (- 2.5 mmHg; 95% CI: - 3.5, - 1.5; p < 0.001) was 14% weight-dependent and 86% weight-independent. For DBP there was limited impact of dulaglutide treatment, with only a small weight-mediated effect. Dulaglutide 4.5 mg demonstrated an effect on reduction in SBP and pulse pressure beyond that of dulaglutide 1.5 mg which was primarily weight mediated.

CONCLUSIONS

Dulaglutide 1.5 mg reduced SBP and pulse pressure in people with T2D across the placebo-controlled trials in the AWARD program. While up to one third of the effect of dulaglutide 1.5 mg on SBP and pulse pressure was due to weight reduction, the majority was independent of weight. A greater understanding of the pleotropic effects of GLP-1 RA that contribute to reduction in blood pressure could support developing future approaches for treating hypertension. Trial registrations (clinicaltrials.gov) NCT01064687, NCT00734474, NCT01769378, NCT02597049, NCT01149421, NCT03495102.

The vascular function effects of adding exenatide or meal insulin to basal insulin therapy in early type 2 diabetes

OBJECTIVE

Basal insulin glargine has a neutral effect on cardiovascular risk in type 2 diabetes (T2DM). In practice, basal insulin is often paired with a glucagon-like peptide-1 receptor agonist (GLP1-RA) or meal insulin; however, the cardiovascular implications of these combinations have not been fully elucidated. In this context, we sought to evaluate the vascular function effects of adding the GLP1-RA exenatide or meal insulin lispro to basal glargine therapy in early T2DM.

METHODS

In this 20-week trial, adults with T2DM of < 7-years duration were randomized to 8-weeks treatment with (i) insulin glargine (Glar), (ii) glargine + thrice-daily lispro (Glar/Lispro), or (iii) glargine + twice-daily exenatide (Glar/Exenatide), followed by 12-weeks washout. At baseline, 8-weeks, and washout, fasting endothelial function was assessed with reactive hyperemia index (RHI) measurement by peripheral arterial tonometry.

RESULTS

At baseline, there were no differences in blood pressure (BP), heart rate (HR) or RHI between participants randomized to Glar (n = 24), Glar/Lispro (n = 24), and Glar/Exenatide (n = 25). At 8-weeks, Glar/Exenatide decreased systolic BP (mean - 8.1 mmHg [95%CI - 13.9 to - 2.4], p = 0.008) and diastolic BP (mean - 5.1 mmHg [- 9.0 to - 1.3], p = 0.012) compared to baseline, with no significant changes in HR or RHI. Notably, baseline-adjusted RHI (mean ± SE) did not differ between the groups at 8-weeks (Glar 2.07 ± 0.10; Glar/Lispro 2.00 ± 0.10; Glar/Exenatide 1.81 ± 0.10; p = 0.19), nor did baseline-adjusted BP or HR. There were no differences between the groups in baseline-adjusted RHI, BP or HR after 12-weeks washout.

CONCLUSION

Adding either exenatide or lispro to basal insulin therapy does not appear to affect fasting endothelial function in early T2DM.

TRIAL REGISTRATION

ClinicalTrials.Gov NCT02194595.

An overview on role of nutrition on COVID-19 immunity: Accumulative review from available studies

The novel coronavirus infection (COVID-19) conveys a serious global threat to health and economy. A common predisposing factor for development to serious progressive disease is presence of a low-grade inflammation, e.g., as seen in diabetes, metabolic syndrome, and heart failure. Micronutrient deficiencies may also contribute to the development of this state. Therefore, the aim of the present study is to explore the role of the nutrition to relieve progression of COVID-19. According PRISMA protocol, we conducted an online databases search including Scopus, PubMed, Google Scholar and web of science for published literatures in the era of COVID-19 Outbreak regarding to the status of nutrition and COVID-19 until December 2021. There were available studies (80 studies) providing direct evidence regarding the associations between the status of nutrition and COVID-19 infection. Adequate nutritional supply is essential for resistance against other viral infections and also for improvement of immune function and reduction of inflammation. Hence, it is suggested that nutritional intervention which secures an adequate status might protect against the novel coronavirus SARS-CoV-2 (Severe Acute Respiratory Syndrome - coronavirus-2) and mitigate its course. We also recommend initiation of adequate nutritional supplementation in high-risk areas and/or soon after the time of suspected infection with SARS-CoV-2. Subjects in high-risk groups should have high priority for applying this nutritive adjuvant therapy that should be started prior to administration of specific and supportive medical measures.

The effect of haptoglobin genotype on the association of asymmetric dimethylarginine and DDAH 1 polymorphism with diabetic macroangiopathy

BACKGROUND

Dimethylarginine dimethylaminohydrolase (DDAH) 1 maintains the bioavailability of nitric oxide by degrading asymmetric dimethylarginine (ADMA). Here, we aimed to investigate the effect of haptoglobin (Hp) genotype on the association of ADMA and DDAH 1 polymorphism with diabetic macroangiopathy.

METHODS

In stage 1, 90 Chinese participants with type 2 diabetes were enrolled to measure a panel of targeted metabolites, including ADMA, using tandem mass spectrometry (BIOCRATES AbsoluteIDQ™ p180 kit). In stage 2, an independent cohort of 2965 Chinese patients with type 2 diabetes was recruited to analyze the effect of Hp genotype on the association between DDAH 1 rs233109 and diabetic macroangiopathy. Hp genotypes were detected using a validated assay based on the TaqMan method. DDAH 1 rs233109 was genotyped by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy using the MassARRAY platform.

RESULTS

In stage 1, serum ADMA levels correlated with common Hp genotypes (β ± SE = - 0.049 ± 0.023, P = 0.035), but not with diabetic macroangiopathy (P = 0.316). In stage 2, the distribution of DDAH 1 rs233109 genotype frequencies was 15% (CC), 47% (TC), and 38% (TT), which was in Hardy-Weinberg equilibrium (P = 0.948). A significant Hp genotype by rs 233109 genotype interaction effect on diabetic macroangiopathy was found (P = 0.017). After adjusting for confounders, patients homozygous for rs233109 CC were more likely to develop diabetic macroangiopathy than those carrying TT homozygotes in the Hp 2-2 subgroup [odds ratio = 1.750 (95% confidence interval, 1.101-2.783), P = 0.018].

CONCLUSION

Hp genotype affects the association between DDAH 1 rs233109 and diabetic macroangiopathy in Chinese patients with type 2 diabetes.

Lung Abnormalities Detected with Hyperpolarized 129Xe MRI in Patients with Long COVID

Background Post-COVID-19 condition encompasses symptoms following COVID-19 infection that linger at least 4 weeks after the end of active infection. Symptoms are wide ranging, but breathlessness is common. Purpose To determine if the previously described lung abnormalities seen on hyperpolarized (HP) pulmonary xenon 129 (129Xe) MRI scans in participants with post-COVID-19 condition who were hospitalized are also present in participants with post-COVID-19 condition who were not hospitalized. Materials and Methods In this prospective study, nonhospitalized participants with post-COVID-19 condition (NHLC) and posthospitalized participants with post-COVID-19 condition (PHC) were enrolled from June 2020 to August 2021. Participants underwent chest CT, HP 129Xe MRI, pulmonary function testing, and the 1-minute sit-to-stand test and completed breathlessness questionnaires. Control subjects underwent HP 129Xe MRI only. CT scans were analyzed for post-COVID-19 interstitial lung disease severity using a previously published scoring system and full-scale airway network (FAN) modeling. Analysis used group and pairwise comparisons between participants and control subjects and correlations between participant clinical and imaging data. Results A total of 11 NHLC participants (four men, seven women; mean age, 44 years ± 11 [SD]; 95% CI: 37, 50) and 12 PHC participants (10 men, two women; mean age, 58 years ±10; 95% CI: 52, 64) were included, with a significant difference in age between groups (P = .05). Mean time from infection was 287 days ± 79 (95% CI: 240, 334) and 143 days ± 72 (95% CI: 105, 190) in NHLC and PHC participants, respectively. NHLC and PHC participants had normal or near normal CT scans (mean, 0.3/25 ± 0.6 [95% CI: 0, 0.63] and 7/25 ± 5 [95% CI: 4, 10], respectively). Gas transfer (Dlco) was different between NHLC and PHC participants (mean Dlco, 76% ± 8 [95% CI: 73, 83] vs 86% ± 8 [95% CI: 80, 91], respectively; P = .04), but there was no evidence of other differences in lung function. Mean red blood cell-to-tissue plasma ratio was different between volunteers (mean, 0.45 ± 0.07; 95% CI: 0.43, 0.47]) and PHC participants (mean, 0.31 ± 0.10; 95% CI: 0.24, 0.37; P = .02) and between volunteers and NHLC participants (mean, 0.37 ± 0.10; 95% CI: 0.31, 0.44; P = .03) but not between NHLC and PHC participants (P = .26). FAN results did not correlate with Dlco) or HP 129Xe MRI results. Conclusion Nonhospitalized participants with post-COVID-19 condition (NHLC) and posthospitalized participants with post-COVID-19 condition (PHC) showed hyperpolarized pulmonary xenon 129 MRI and red blood cell-to-tissue plasma abnormalities, with NHLC participants demonstrating lower gas transfer than PHC participants despite having normal CT findings. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Parraga and Matheson in this issue.

Deep-learning-based hepatic fat assessment (DeHFt) on non-contrast chest CT and its association with disease severity in COVID-19 infections: A multi-site retrospective study

Background

Hepatic steatosis (HS) identified on CT may provide an integrated cardiometabolic and COVID-19 risk assessment. This study presents a deep-learning-based hepatic fat assessment (DeHFt) pipeline for (a) more standardised measurements and (b) investigating the association between HS (liver-to-spleen attenuation ratio <1 in CT) and COVID-19 infections severity, wherein severity is defined as requiring invasive mechanical ventilation, extracorporeal membrane oxygenation, death.

Methods

DeHFt comprises two steps. First, a deep-learning-based segmentation model (3D residual-UNet) is trained (N = 80) to segment the liver and spleen. Second, CT attenuation is estimated using slice-based and volumetric-based methods. DeHFt-based mean liver and liver-to-spleen attenuation are compared with an expert's ROI-based measurements. We further obtained the liver-to-spleen attenuation ratio in a large multi-site cohort of patients with COVID-19 infections (D1, N = 805; D2, N = 1917; D3, N = 169) using the DeHFt pipeline and investigated the association between HS and COVID-19 infections severity.

Findings

The DeHFt pipeline achieved a dice coefficient of 0.95, 95% CI [0.93–0.96] on the independent validation cohort (N = 49). The automated slice-based and volumetric-based liver and liver-to-spleen attenuation estimations strongly correlated with expert's measurement. In the COVID-19 cohorts, severe infections had a higher proportion of patients with HS than non-severe infections (pooled OR = 1.50, 95% CI [1.20–1.88], P < .001).

Interpretation

The DeHFt pipeline enabled accurate segmentation of liver and spleen on non-contrast CTs and automated estimation of liver and liver-to-spleen attenuation ratio. In three cohorts of patients with COVID-19 infections (N = 2891), HS was associated with disease severity. Pending validation, DeHFt provides an automated CT-based metabolic risk assessment.

Funding

For a full list of funding bodies, please see the Acknowledgements.

Calculation of an Improved Stiffness Index Using Decomposed Radial Pulse and Digital Volume Pulse Signals

The stiffness index (SI) is used to estimate cardiovascular risk in humans. In this study, we developed a refined SI for determining arterial stiffness based on the decomposed radial pulse and digital volume pulse (DVP) waveforms. In total, 40 mature asymptomatic subjects (20 male and 20 female, 42 to 76 years of age) and 40 subjects with type 2 diabetes mellitus (T2DM) (23 male and 17 female, 35 to 78 years of age) were enrolled in this study. We measured subjects' radial pulse at the wrist and their DVP at the fingertip, and then implemented ensemble empirical mode decomposition (EEMD) to derive the orthogonal intrinsic mode functions (IMFs). An improved SI (SI_new) was calculated by dividing the body height by the mean transit time between the first IMF5 peak and the IMF6 trough. Another traditional index, pulse wave velocity (PWV_finger), was also included for comparison. For the PWV_finger index, the subjects with T2DM presented significantly higher SI_new values measured according to the radial pulse (SI_new-RP) and DVP signals (SI_new-DVP). Using a one-way analysis of variance, we found no statistically significant difference between SI_new-RP and PWV_finger when applied to the same test subjects. Binary logistic regression analysis showed that a high SI_new-RP value was the most significant risk factor for developing T2DM (SI_new-RP odds ratio 3.17, 95% CI 1.53-6.57; SI_new-DVP odds ratio 2.85, 95% CI 1.27-6.40). Our refined stiffness index could provide significant information regarding the decomposed radial pulse and digital volume pulse signals in assessments of arterial stiffness.

Influence of endothelial function and arterial stiffness on the behavior of cervicocephalic arterial dissections: An observational study

Background

The mechanical and physiological properties of the arterial wall might affect the behavior of spontaneous cervicocephalic arterial dissections (CCAD). We aimed to determine the effects of endothelial function and arterial stiffness on the clinical characteristics and outcomes of CCAD using brachial flow-mediated dilation (FMD) and brachial-ankle pulse wave velocity (PWV).

Methods

From a single-center database, we identified patients admitted from April 2011 to December 2021 with a diagnosis of CCAD who underwent both FMD and PWV. FMD was classified as normal and decreased according to institutional thresholds. PWV was categorized into tertiles. Comparative and multivariable analyses were performed to determine the effects of FMD and PWV values on major clinical outcomes.

Results

A total of 146 patients (age: 47 ± 11 years; men: 77.4%) were included. The main presentation was ischemic stroke in 76.7% of the patients, while 23.3% presented with headache or other symptoms. Healing of the dissection was observed in 55.8%. In multivariable analysis, Normal FMD levels (vs. decreased; adjusted OR: 4.52, 95% CI [1.95 −10.52]) were associated with spontaneous healing of the dissection. Highest PWV tertile (vs. lowest; adjusted OR: 17.05, 95% CI [3.07–94.82]) was associated with ischemic presentation. There was a higher ischemic stroke recurrence in the 3rd PWV tertile, and more frequent aneurysmal enlargement in the lowest PWV tertile, but their frequency was low, precluding multivariable analysis.

Conclusion

In spontaneous CCAD, preserved endothelial function was associated with spontaneous arterial healing. Arterial stiffness is associated with ischemic presentation.

Effect of sodium-glucose co-transporter-2 inhibitors on arterial stiffness: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Arterial stiffness represents an established cardiovascular risk marker. Sodium-glucose co-transporter-2 (SGLT-2) inhibitors have significant cardio-protective effects. Herein we sought to determine the effect of SGLT-2 inhibitors on pulse wave velocity (PWV).

METHODS

We searched PubMed, Cochrane Library, and grey literature from inception to 7^th February 2022 for randomized controlled trials (RCTs) enrolling adult subjects with or without type 2 diabetes mellitus (T2DM), assigned to a SGLT-2 inhibitor versus control and addressing their effect on PWV. We set as primary efficacy outcome the change in PWV with SGLT-2 inhibitors versus placebo or control.

RESULTS

We pooled data from six trials in a total of 452 enrolled participants assigned either to SGLT-2 inhibitor or control. Overall, SGLT-2 inhibitor treatment compared to control resulted in a nonsignificant decrease in PWV. Exclusion of a trial utilizing cardiac magnetic resonance imaging for the assessment of PWV demonstrated that SGLT-2 inhibitors induce a significant reduction in PWV by 0.21 m/s. When we restricted our analysis to RCTs enrolling subjects with T2DM, we observed that SGLT-2 inhibitor compared to control resulted in a significant decrease in PWV by 0.17 m/s.

CONCLUSION

SGLT-2 inhibitors do not decrease PWV in patients with established cardiovascular disease or cardiovascular risk factors. However, we have shown that SGLT-2 inhibitors lead to a slight, but significant decrease in PWV in patients with T2DM. The latter finding is of great value, based on the significant correlation between PWV and micro- and macro-vascular complications of T2DM.

Lipid Profile Changes Associated with SGLT-2 Inhibitors and GLP-1 Agonists in Diabetes and Metabolic Syndrome

The introduction of sodium glucose transporter-2 inhibitors and glucagon-like peptide-1 receptor agonists in type 2 diabetes mellitus treatment has shown an unexpectedly significant improvement in heart disease outcome trials. Although they have very different modes of action, a portion of the salutary cardiovascular disease improvement may be related to their impact on diabetic dyslipidemia. As discussed in this focused review, the sodium glucose transporter-2 inhibitors as a class show a mild increase in low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol levels, while triglycerides (TG) decrease inconsistently. In particular, the rise in LDL appears to be related to the less atherogenic, large buoyant LDL particles. The glucagon-like peptide-1 receptor agonists show more of an impact on weight loss and improvement in the underlying low HDL and high TG dyslipidemia. The effect of sodium glucose transporter-2 inhibitors and glucagon-like peptide 1 receptor agonists when used in combination remains largely unknown. Also unexplored is difference in effect of these medications among various ethnicities and metabolic syndrome.

Endocrine system dysfunction and chronic heart failure: a clinical perspective

Chronic heart failure (CHF) leads to an excess of urgent ambulatory visits, recurrent hospital admissions, morbidity, and mortality regardless of medical and non-medical management of the disease. This excess of risk may be attributable, at least in part, to comorbid conditions influencing the development and progression of CHF. In this perspective, the authors examined and described the most common endocrine disorders observed in patients with CHF, particularly in individuals with reduced ejection fraction, aiming to qualify the risks, quantify the epidemiological burden and discuss about the potential role of endocrine treatment. Thyroid dysfunction is commonly observed in patients with CHF, and sometimes it could be the consequence of certain medications (e.g., amiodarone). Male and female hypogonadism may also coexist in this clinical context, contributing to deteriorating the prognosis of these patients. Furthermore, growth hormone deficiency may affect the development of adult myocardium and predispose to CHF. Limited recommendation suggests to screen endocrine disorders in CHF patients, but it could be interesting to evaluate possible endocrine dysfunction in this setting, especially when a high suspicion coexists. Data referring to long-term safety and effectiveness of endocrine treatments in patients with CHF are limited, and their impact on several "hard" endpoints (such as hospital admission, all-cause, and cardiovascular mortality) are still poorly understood.

Glucagon-Like Peptide-1 Receptor Agonists and Dual Glucose-Dependent Insulinotropic Polypeptide/Glucagon-Like Peptide-1 Receptor Agonists in the Treatment of Obesity/Metabolic Syndrome, Prediabetes/Diabetes and Non-Alcoholic Fatty Liver Disease-Current Evidence

The obesity pandemic is accompanied by increased risk of developing metabolic syndrome (MetS) and related conditions: non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH), type 2 diabetes mellitus (T2DM) and cardiovascular (CV) disease (CVD). Lifestyle, as well as an imbalance of energy intake/expenditure, genetic predisposition, and epigenetics could lead to a dysmetabolic milieu, which is the cornerstone for the development of cardiometabolic complications. Glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) and dual glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 RAs promote positive effects on most components of the "cardiometabolic continuum" and consequently help reduce the need for polypharmacy. In this review, we highlight the main pathophysiological mechanisms and risk factors (RFs), that could be controlled by GLP-1 and dual GIP/GLP-1 RAs independently or through synergism or differences in their mode of action. We also address the evidence on the use of GLP-1 and dual GIP/GLP-1 RAs in the treatment of obesity, MetS and its related conditions (prediabetes, T2DM and NAFLD/NASH). In conclusion, GLP-1 RAs have already been established for the treatment of T2DM, obesity and cardioprotection in T2DM patients, while dual GIP/GLP-1 RAs appear to have the potential to possibly surpass them for the same indications. However, their use in the prevention of T2DM and the treatment of complex cardiometabolic metabolic diseases, such as NAFLD/NASH or other metabolic disorders, would benefit from more evidence and a thorough clinical patient-centered approach. There is a need to identify those patients in whom the metabolic component predominates, and whether the benefits outweigh any potential harm.

Phenoxy pendant isatins as potent α-glucosidase inhibitors: reciprocal carbonyl⋯carbonyl interactions, antiparallel π⋯π stacking driven solid state self-assembly and biological evaluation

Carbonyl–carbonyl (CO⋯CO) interactions are recently explored noncovalent interactions of significant interest owing to their role in the stability of biomacromolecules. Currently, substantial efforts are being made to understand the nature of these interactions. In this study, twelve phenoxy pendant isatins 1–12 have been evaluated for their α-glucosidase inhibitory potential in addition to the analysis of X-ray single crystals of 4 and 9. Both compounds 4 and 9 showed intriguing and unique self-assembled structures. The CO⋯CO and antiparallel displaced π⋯π stacking interactions are mainly involved in the formation of 1D-stair like supramolecular chains of 4 whereas antiparallel π⋯π stacking interactions drive the formation of 1D-columnar stacks of 9. These compounds not only highlight the potential of the isatin moiety in forming strong CO⋯CO and antiparallel π⋯π stacking interactions but also are interesting models to provide considerable insight into the nature of these interactions. The in vitro biological studies revealed that all twelve phenoxy pendant isatins 1–12 are highly potent inhibitors of α-glucosidase enzyme with IC₅₀ values ranging from 5.32 ± 0.17 to 150.13 ± 0.62 μM, showing many fold more potent activity than the standard drug, acarbose (IC₅₀ = 873.34 ± 1.67). Easy access and high α-glucosidase inhibition potential of these phenoxy pendant isatins 1–12 provide an attractive platform for finding more effective medication for controlling postprandial hyperglycemia.

Carbonyl–carbonyl (CO⋯CO) interactions are recently explored noncovalent interactions of significant interest owing to their role in the stability of biomacromolecules.

Expression of SARS-CoV-2 receptor "ACE2" in human pancreatic β cells: to be or not to be!

The current COVID-19 pandemic, which continues to spread across the globe, is caused by severe acute respiratory syndrome coronavirus (SARS-Cov-2). Soon after the pandemic emerged in China, it became clear that the receptor-binding domain (RBD) of angiotensin-converting enzyme 2 (ACE2) serves as the primary cell surface receptor for SARS-Cov-2. Subsequent work has shown that diabetes and hyperglycemia are major risk factors for morbidity and mortality in COVID-19 patients. However, data on the pattern of expression of ACE2 on human pancreatic β cells remain contradictory. Additionally, there is no consensus on whether the virus can directly infect and damage pancreatic islets and hence exacerbate diabetes. In this mini-review, we highlight the role of ACE2 receptor and summarize the current state of knowledge regarding its expression/co-localization in human pancreatic endocrine cells. We also discuss recent data on the permissiveness of human pancreatic β cells to SARS-Cov-2 infection.

Pathophysiological Association between Diabetes Mellitus and Endothelial Dysfunction

Endothelial dysfunction plays a critical role in atherosclerosis progression, leading to cardiovascular complications. There are significant associations between diabetes mellitus, oxidative stress, and endothelial dysfunction. Oxidative stress is increased by chronic hyperglycemia and acute glucose fluctuations induced by postprandial hyperglycemia in patients with diabetes mellitus. In addition, selective insulin resistance in the phosphoinositide 3-kinase/Akt/endothelial nitric oxide (NO) synthase pathway in endothelial cells is involved in decreased NO production and increased endothelin-1 production from the endothelium, resulting in endothelial dysfunction. In a clinical setting, selecting an appropriate therapeutic intervention that improves or augments endothelial function is important for preventing diabetic vascular complications. Hypoglycemic drugs that reduce glucose fluctuations by decreasing the postprandial rise in blood glucose levels, such as glinides, α-glucosidase inhibitors and dipeptidyl peptidase 4 inhibitors, and hypoglycemic drugs that ameliorate insulin sensitivity, such as thiazolidinediones and metformin, are expected to improve or augment endothelial function in patients with diabetes. Glucagon-like peptide 1 receptor agonists, metformin, and sodium-glucose cotransporter 2 inhibitors may improve endothelial function through multiple mechanisms, some of which are independent of glucose control or insulin signaling. Oral administration of antioxidants is not recommended in patients with diabetes due to the lack of evidence for the efficacy against diabetic complications.

Dysfunctional High-Density Lipoproteins in Type 2 Diabetes Mellitus: Molecular Mechanisms and Therapeutic Implications

High density lipoproteins (HDLs) are commonly known for their anti-atherogenic properties that include functions such as the promotion of cholesterol efflux and reverse cholesterol transport, as well as antioxidant and anti-inflammatory activities. However, because of some chronic inflammatory diseases, such as type 2 diabetes mellitus (T2DM), significant changes occur in HDLs in terms of both structure and composition. These alterations lead to the loss of HDLs’ physiological functions, to transformation into dysfunctional lipoproteins, and to increased risk of cardiovascular disease (CVD). In this review, we describe the main HDL structural/functional alterations observed in T2DM and the molecular mechanisms involved in these T2DM-derived modifications. Finally, the main available therapeutic interventions targeting HDL in diabetes are discussed.

Normalisation of glucose metabolism by exendin-4 in the chronic phase after stroke promotes functional recovery in male diabetic mice

BACKGROUND AND PURPOSE

Glucagon-like peptide-1 (GLP-1) receptor activation decreases stroke risk in people with Type 2 diabetes (T2D), while animal studies have shown the efficacy of this strategy to counteract stroke-induced acute brain damage. However, whether GLP-1 receptor activation also improves recovery in the chronic phase after stroke is unknown. We investigated whether post-acute, chronic administration of the GLP-1 receptor agonist, exendin-4, improves post-stroke recovery and examined possible underlying mechanisms in T2D and non-T2D mice.

EXPERIMENTAL APPROACH

We induced stroke via transient middle cerebral artery occlusion (tMCAO) in T2D/obese mice (8 months of high-fat diet) and age-matched controls. Exendin-4 was administered for 8 weeks from Day 3 post-tMCAO. We assessed functional recovery by weekly upper-limb grip strength tests. Insulin sensitivity and glycaemia were evaluated at 4 and 8 weeks post-tMCAO. Neuronal survival, stroke-induced neurogenesis, neuroinflammation, atrophy of GABAergic parvalbumin+ interneurons, post-stroke vascular remodelling and fibrotic scar formation were investigated by immunohistochemistry.

KEY RESULTS

Exendin-4 normalised T2D-induced impairment of forepaw grip strength recovery in correlation with normalised glycaemia and insulin sensitivity. Moreover, exendin-4 counteracted T2D-induced atrophy of parvalbumin+ interneurons and decreased microglia activation. Finally, exendin-4 normalised density and pericyte coverage of micro-vessels and restored fibrotic scar formation in T2D mice. In non-T2D mice, the exendin-4-mediated recovery was minor.

CONCLUSION AND IMPLICATIONS

Chronic GLP-1 receptor activation mediates post-stroke functional recovery in T2D mice by normalising glucose metabolism and improving neuroplasticity and vascular remodelling in the recovery phase. The results warrant clinical trial of GLP-1 receptor agonists for rehabilitation after stroke in T2D.