Compromised cardiac autonomic function in non-diabetic subjects with 1 h post-load hyperglycemia: a cross-sectional study.

BACKGROUND: A compromised cardiac autonomic function has been found in subjects with insulin resistance related disorders such as obesity, impaired glucose tolerance (IGT) and type 2 diabetes and confers an increased risk of adverse cardiovascular outcomes. Growing evidence indicate that 1 h plasma glucose levels (1hPG) during an oral glucose tolerance test (OGTT) ≥ 155 mg/dl identify amongst subjects with normal glucose tolerance (NGT) a new category of prediabetes (NGT 1 h-high), harboring an increased risk of cardiovascular organ damage. In this study we explored the relationship between 1 h post-load hyperglycemia and cardiac autonomic dysfunction. METHODS: Presence of cardiac autonomic neuropathy (CAN) defined by cardiovascular autonomic reflex tests (CARTs) and heart rate variability (HRV), assessed by 24-h electrocardiography were evaluated in 88 non-diabetic subjects subdivided on the basis of OGTT data in: NGT with 1 h PG < 155 mg/dl (NGT 1 h-low), NGT 1 h-high and IGT. RESULTS: As compared to subjects with NGT 1 h-low, those with NGT 1 h-high and IGT were more likely to have CARTs defined CAN and reduced values of the 24 h time domain HVR parameters including standard deviation of all normal heart cycles (SDNN), standard deviation of the average RR interval for each 5 min segment (SDANN), square root of the differences between adjacent RR intervals (RMSSD), percentage of beats with a consecutive RR interval difference > 50 ms (PNN50) and Triangular index. Univariate analyses showed that 1hPG, but not fasting and 2hPG, was inversely associated with all the explored HVR parameters and positively with CARTs determined presence of CAN. In multivariate regression analysis models including several confounders we found that 1hPG was an independent contributor of HRV and presence of CAN. CONCLUSION: Subjects with 1hPG ≥ 155 mg/dl have an impaired cardiac autonomic function.

Association between augmented levels of the gut pro-hormone Proneurotensin and subclinical vascular damage.

Elevated levels of the gut pro-hormone Proneurotensin (proNT) have been found to predict development of cardiovascular disease. However, it is still unknown whether higher proNT levels are associated with subclinical vascular damage. Herein, we investigated the relationship between higher proNT concentrations and augmented pulse pressure (PP) and carotid intima-media thickness (cIMT), indicators of increased arterial stiffness and subclinical atherosclerosis, respectively. Clinical characteristics, PP and cIMT were evaluated in 154 non-diabetic individuals stratified into tertiles according to fasting serum proNT concentrations. We found that, subjects with higher proNT levels exhibited a worse lipid profile and insulin sensitivity, increased C-reactive protein levels, along with higher values of PP and cIMT as compared to the lowest proNT tertile. Prevalence of elevated PP (≥ 60 mmHg) and subclinical carotid atherosclerosis (IMT > 0.9 mm) was increased in the highest tertile of proNT. In a logistic regression analysis adjusted for several confounders, subjects with higher proNT levels displayed a fivefold raised risk of having elevated PP values (OR 5.36; 95%CI 1.04-27.28; P = 0.05) and early carotid atherosclerosis (OR 4.81; 95%CI 1.39-16.57; P = 0.01) as compared to the lowest proNT tertile. In conclusion, higher circulating levels of proNT are a biomarker of subclinical vascular damage independent of other atherosclerotic risk factors.

Profiles of sulfonylurea use in Diabetes Mellitus type 2: an analysis of clinical practice over the last 10 years.

AIMS: Describing the evolution over time in the use of sulfonylureas (SUs) and the characteristics of patients at first prescription and at interruption of treatment with SUs. METHODS: Retrospective evaluation of data from the Italian Association of Diabetologists (AMD) Annals registry (2010-2020), about T2D patients who started treatment with SUs. The longitudinal probability of remaining on SUs was estimated by Kaplan Meier survival curves. RESULTS: SU prescription decreased from 30.7 % (2010) to 12.9 % (2020). Patients started on SU were 68.2 ± 11.2 years old, mostly males (55.5 %), with diabetes duration = 10.1 ± 8.3 years, BMI = 29.7 ± 5.5 kg/m2, and HbA1c = 8.3 ± 1.7 % [67 mmol/mol]. After one year, the probability of staying on SU was 85.4 %, 75.9 % after two years, 68.2 % after 3 years, 56.6 % after 5 years. Patients who discontinued SUs had higher BMI and HbA1c, were younger, more often males and treated with insulin. Over time, the percentage of subjects switched to metformin, DPP4i, SGLT2i, and GLP1RA increased, whereas use of glinides, glitazones, acarbose and insulin declined. CONCLUSIONS: These data suggest a consensus, slowly, but increasingly aligning with the current National indications of dismissing SUs for the treatment of T2D. The new drugs for diabetes should represent a preferable choice in all patients who do not have specific contraindications.

Glucagon kinetics assessed by mathematical modelling during oral glucose administration in people spanning from normal glucose tolerance to type 2 diabetes.

Background/Objectives: Glucagon is important in the maintenance of glucose homeostasis, with also effects on lipids. In this study, we aimed to apply a recently developed model of glucagon kinetics to determine the sensitivity of glucagon variations (especially, glucagon inhibition) to insulin levels ("alpha-cell insulin sensitivity"), during oral glucose administration. Subjects/Methods: We studied 50 participants (spanning from normal glucose tolerance to type 2 diabetes) undergoing frequently sampled 5-hr oral glucose tolerance test (OGTT). The alpha-cell insulin sensitivity and the glucagon kinetics were assessed by a mathematical model that we developed previously. Results: The alpha-cell insulin sensitivity parameter (named SGLUCA; "GLUCA": "glucagon") was remarkably variable among participants (CV=221%). SGLUCA was found inversely correlated with the mean glycemic values, as well as with 2-hr glycemia of the OGTT. When stratifying participants into two groups (normal glucose tolerance, NGT, N=28, and impaired glucose regulation/type 2 diabetes, IGR_T2D, N=22), we found that SGLUCA was lower in the latter (1.50 ± 0.50·10-2 vs. 0.26 ± 0.14·10-2 ng·L-1 GLUCA/pmol·L-1 INS, in NGT and IGR_T2D, respectively, p=0.009; "INS": "insulin"). Conclusions: The alpha-cell insulin sensitivity is highly variable among subjects, and it is different in groups at different glucose tolerance. This may be relevant for defining personalized treatment schemes, in terms of dietary prescriptions but also for treatments with glucagon-related agents.

Myocardial mechano-energetic efficiency is not impaired in patients with metabolically healthy overweight and obesity.

OBJECTIVE: Reduced myocardial mechano-energetic efficiency (MEE) was associated with BMI. Subgroups of individuals with increased BMI but favorable cardiovascular risk profile were identified as individuals with "metabolically healthy overweight" (MHOW) and "metabolically healthy obesity" (MHO), respectively. We aim to investigate whether those with MHOW/MHO, defined as those having none of the components of metabolic syndrome, exhibit impaired MEE compared with their unhealthy counterparts. METHODS: Myocardial MEE per gram of left ventricular mass (MEEi) was assessed by echocardiography in 2190 nondiabetic individuals participating in the CATAnzaro MEtabolic RIsk factors (CATAMERI) study who were divided, according to BMI and metabolic status, into groups of individuals with metabolically healthy normal weight (MHNW), metabolically unhealthy normal weight (MUNW), MHOW, metabolically unhealthy overweight (MUOW), MHO, and metabolically unhealthy obesity (MUO). RESULTS: After adjusting for age and sex, no differences in myocardial MEEi were observed among individuals with MHNW, MHOW, and MHO (p = 0.56). Myocardial MEEi was comparable among individuals with MUNW, MUOW, and MUO (p = 0.21). Individuals with MHNW, MHOW, and MHO displayed significantly higher myocardial MEEi compared with their unhealthy counterparts. CONCLUSIONS: Increased BMI is not an obligate determinant for reduced myocardial MEEi. Other known components of metabolic syndrome rather than increased BMI contributed to reduced myocardial MEEi.

Asymmetric dimethylarginine (ADMA) is associated with reduced myocardial mechano-energetic efficiency in hypertensive subjects.

BACKGROUND AND AIMS: Our prior study showed that endothelial dysfunction contributed to reduced myocardial mechano-energetics efficiency (MEEi) independently of several confounders. Reduced activity of endothelial nitric oxide synthase may be due to increased levels of the endogenous inhibitor asymmetric dimethylarginine (ADMA). The impact of ADMA on myocardial MEEi has not been determined yet. This study aims to investigate the association between plasma ADMA levels and MEEi in drug-naïve hypertensive individuals. METHODS AND RESULTS: 63 hypertensive individuals participating in the CATAnzaro MEtabolic RIsk factors (CATAMERI) study were included. All participants underwent to an echocardiogram for myocardial MEEi measurement. ADMA plasma concentrations were measured by high-performance liquid chromatography. A multivariate linear regression analysis was conducted to investigate the independent association between ADMA levels and MEEi. In a univariate analysis, ADMA levels were significantly associated with myocardial MEEi (r = 0.438; P < 0.001). In a multivariate regression analysis, plasma ADMA levels were associated to decreased myocardial MEEi (ß = 0.458, P < 0.001) independently of well-established cardiovascular risk factors including age, sex, BMI, waist circumference, smoking status, total cholesterol and HDL, triglycerides, glucose tolerance status, and HOMA-IR index of insulin resistance. CONCLUSIONS: ADMA may contribute to reduced myocardial MEEi by reducing nitric oxide bioavailability.

One-hour post-load glucose levels are associated with hepatic steatosis assessed by transient elastography.

AIM: To examine the association between 1-hour plasma glucose (PG) concentration and markers of non-alcoholic fatty liver disease (NAFLD) assessed by transient elastography (TE). METHODS: We performed TE in 107 metabolically well-characterized non-diabetic White individuals. Controlled attenuation parameter (CAP) was used to quantify liver steatosis, while liver stiffness marker (LS) was used to evaluate fibrosis. RESULTS: Controlled attenuation parameter correlated significantly with 1-hour PG (r = 0.301, P < 0.01), fasting insulin (r = 0.285, P < 0.01), 2-hour insulin (r = 0.257, P < 0.02), homeostasis model assessment index of insulin resistance (r = 0.252, P < 0.01), high-density lipoprotein cholesterol (r = -0.252, P < 0.02), body mass index (BMI; r = 0.248, P < 0.02) and age (r = 0.212, P < 0.03), after correction for age, sex and BMI. In a multivariable linear regression analysis, 1-hour PG (ß = 0.274, P = 0.008) and fasting insulin levels (ß = 0.225, P = 0.029) were found to be independent predictors of CAP. After excluding subjects with prediabetes, 1-hour PG was the sole predictor of CAP variation (ß = 0.442, P < 0.001). In a logistic regression model, we observed that the group with 1-hour PG ≥ 8.6 mmol/L (155 mg/dL) had a significantly higher risk of steatosis (odds ratio 3.98, 95% confidence interval 1.43-11.13; P = 0.008) than individuals with 1-hour PG < 8.6 mmol/L, after correction for potential confounders. No association was observed between 1-hour PG and LS. CONCLUSION: Our data confirm that 1-hour PG ≥ 8.6 mmol/L is associated with higher signs of NAFLD, even among individuals with normal glucose tolerance, categorized as low risk by canonical diagnostic standards. TE is a safe low-impact approach that could be employed for stratifying the risk profile in these patients, with a high level of accuracy.

Endothelial dysfunction is associated with reduced myocardial mechano-energetic efficiency in drug-naïve hypertensive individuals.

Impaired myocardial mechano-energetics efficiency (MEE) was shown to predict incident heart failure, but pathophysiological mechanisms linking impaired MEE with heart failure have not been elucidated. Endothelial dysfunction is a plausible candidate because it has been associated with heart failure. This study aims to investigate the association between MEE and endothelium-dependent vasodilation, among drug-naïve hypertensive individuals. 198 Drug-naïve hypertensive individuals participating in the CATAnzaro MEtabolic RIsk factors (CATAMERI) study were included. All participants underwent to an oral glucose tolerance test and to an echocardiogram for myocardial LVM-normalized mechano-energetic efficiency (MEEi) measurement. Endothelial-dependent and endothelial-independent vasodilatation were measured by strain-gauge plethysmography during intra-arterial infusion of acetylcholine and sodium nitroprusside, respectively. A multivariate linear regression analysis was conducted to investigate the independent association between maximal endothelial-dependent vasodilation and MEEi. Maximal ACh-stimulated forearm blood flow (FBF) was associated to decreased myocardial MEEi (ß = 0.205, p = 0.002) independently of well-established cardiovascular risk factors including age, sex, BMI, waist circumference, smoking status, total and HDL cholesterol, triglycerides, hsCRP, glucose tolerance status, and HOMA-IR index of insulin resistance. Conversely, no association was observed between SNP-stimulated vasodilation and MEEi. Endothelium-mediated vasodilation may contribute to reduce myocardial MEEi independently of several potential confounders. Because diminished myocardial MEE has been previously associated with incident heart failure, a non-invasive assessment of myocardial MEEi may improve the identification of individuals at higher cardiovascular risk who may benefit from the initiation of pharmacological treatments ameliorating the endothelial dysfunction.

Liver fibrosis is associated with an increased risk of non-fatal myocardial infarction.

INTRODUCTION: Liver fibrosis is a risk factor for liver-related adverse outcomes and cardiovascular disease (CVD). Recently, the non-invasive Hepamet fibrosis score (HFS) has been validated as a tool capable to identify with good diagnostic accuracy subjects with advanced liver fibrosis. It is unsettled whether HFS is capable to identify individuals at higher risk of CVD. To investigate whether individuals with liver fibrosis measured with HFS have higher risk of myocardial infarction (MI) in adults participating in the CATAnzaro MEtabolic RIsk factors (CATAMERI) study. METHODS: Participants (n = 2948) were divided into three groups according to HFS: low risk of fibrosis (<0.12); intermediate risk of fibrosis (≥0.12 to <0.47); high risk of fibrosis (≥0.47). The association between the liver fibrosis risk and MI was analysed by a logistic regression analysis. RESULTS: As compared with those having the lowest risk (5.3%), a higher proportion of subjects with moderate or high risk of liver fibrosis had MI (12.9% and 24.4%, respectively; p < 0.001). In a logistic regression analysis, individuals at increased risk of liver fibrosis exhibited a threefold increased risk of having MI as compared to those with low risk (OR 3.18; 95% CI 1.31-7.70) independently of confounders including smoking, cholesterol, triglycerides, anti-hypertensive, lipid-lowering and glucose-lowering therapies. CONCLUSIONS: In this cross-sectional study, individuals with higher values of HFS show a higher risk of MI, suggesting that HFS may be a useful tool to identify not only individuals with liver fibrosis but also those at the increased risk of CVD.

Analysis of age-dependent gene-expression in human tissues for studying diabetes comorbidities.

The study of the relationship between type 2 diabetes mellitus (T2DM) disease and other pathologies (comorbidities), together with patient age variation, poses a challenge for medical research. There is evidence that patients affected by T2DM are more likely to develop comorbidities as they grow older. Variation of gene expression can be correlated to changes in T2DM comorbidities insurgence and progression. Understanding gene expression changes requires the analysis of large heterogeneous data at different scales as well as the integration of different data sources into network medicine models. Hence, we designed a framework to shed light on uncertainties related to age effects and comorbidity by integrating existing data sources with novel algorithms. The framework is based on integrating and analysing existing data sources under the hypothesis that changes in the basal expression of genes may be responsible for the higher prevalence of comorbidities in older patients. Using the proposed framework, we selected genes related to comorbidities from existing databases, and then analysed their expression with age at the tissues level. We found a set of genes that changes significantly in certain specific tissues over time. We also reconstructed the associated protein interaction networks and the related pathways for each tissue. Using this mechanistic framework, we detected interesting pathways related to T2DM whose genes change their expression with age. We also found many pathways related to insulin regulation and brain activities, which can be used to develop specific therapies. To the best of our knowledge, this is the first study that analyses such genes at the tissue level together with age variations.

Metabolic Syndrome and C-reactive Protein are Associated With a Reduced Myocardial Mechano-energetic Efficiency.

CONTEXT: Metabolic syndrome and elevated high-sensitivity C-reactive protein (hsCRP) levels are associated with risk of cardiovascular diseases. A reduced myocardial mechano-energetic efficiency (MEE) has been found to be an independent predictor of cardiovascular disease. OBJECTIVE: To evaluate the association between metabolic syndrome and hsCRP levels with impaired MEE. METHODS: Myocardial MEE was assessed by a validated echocardiography-derived measure in 1975 nondiabetic and prediabetic individuals subdivided into 2 groups according to the presence of metabolic syndrome. RESULTS: Individuals with metabolic syndrome exhibited increased stroke work and myocardial oxygen consumption estimated by rate pressure product, and a reduced MEE per gram of left ventricular mass (MEEi) compared with subjects without metabolic syndrome, after adjusting for age and sex. Myocardial MEEi progressively decreased in parallel with the increase in the number of metabolic syndrome components. In a multivariable regression analysis, both metabolic syndrome and hsCRP contributed to reduced myocardial MEEi independently of sex, total cholesterol, high-density lipoprotein, triglycerides, fasting, and 2-hour postload glucose levels. When the study population was divided into 4 groups by the presence or absence of metabolic syndrome and by hsCRP levels above and below 3 mg/L, hsCRP levels ≥3 mg/L were associated with reduced myocardial MEEi both in subjects with metabolic syndrome and in those without the syndrome. CONCLUSION: Nondiabetic and prediabetic individuals with metabolic syndrome exhibit increased stroke work and myocardial oxygen consumption, and an impaired MEEi, an established predictor of adverse cardiovascular events, and elevated hsCRP levels in combination with metabolic syndrome aggravate the myocardial MEEi impairment.

Glucagon induces the hepatic expression of inflammatory markers in vitro and in vivo.

Glucagon exerts multiple hepatic actions, including stimulation of glycogenolysis/gluconeogenesis. The liver plays a crucial role in chronic inflammation by synthesizing proinflammatory molecules, which are thought to contribute to insulin resistance and hyperglycaemia. Whether glucagon affects hepatic expression of proinflammatory cytokines and acute-phase reactants is unknown. Herein, we report a positive relationship between fasting glucagon levels and circulating interleukin (IL)-1ß (r = 0.252, p = .042), IL-6 (r = 0.230, p = .026), fibrinogen (r = 0.193, p = .031), complement component 3 (r = 0.227, p = .024) and high sensitivity C-reactive protein (r = 0.230, p = .012) in individuals without diabetes. In CD1 mice, 4-week continuous treatment with glucagon induced a significant increase in circulating IL-1ß (p = .02), and IL-6 (p = .001), which was countered by the contingent administration of the glucagon receptor antagonist, GRA-II. Consistent with these results, we detected a significant increase in the hepatic activation of inflammatory pathways, such as expression of NLRP3 (p < .02), and the phosphorylation of nuclear factor kappaB (NF-κB; p < .02) and STAT3 (p < .01). In HepG2 cells, we found that glucagon dose-dependently stimulated the expression of IL-1ß (p < .002), IL-6 (p < .002), fibrinogen (p < .01), complement component 3 (p < .01) and C-reactive protein (p < .01), stimulated the activation of NLRP3 inflammasome (p < .01) and caspase-1 (p < .05), induced the phosphorylation of TRAF2 (p < .01), NF-κB (p < .01) and STAT3 (p < .01). Preincubating cells with GRA-II inhibited the ability of glucagon to induce an inflammatory response. Using HepaRG cells, we confirmed the dose-dependent ability of glucagon to stimulate the expression of NLRP3, the phosphorylation of NF-κB and STAT3, in the absence of GRA-II. These results suggest that glucagon has proinflammatory effects that may participate in the pathogenesis of hyperglycaemia and unfavourable cardiometabolic risk profile.

Chemical Compounds and Ambient Factors Affecting Pancreatic Alpha-Cells Mass and Function: What Evidence?

The exposure to different substances present in the environment can affect the ability of the human body to maintain glucose homeostasis. Some review studies summarized the current evidence about the relationships between environment and insulin resistance or beta-cell dysfunction. Instead, no reviews focused on the relationships between the environment and the alpha cell, although in recent years clear indications have emerged for the pivotal role of the alpha cell in glucose regulation. Thus, the aim of this review was to analyze the studies about the effects of chemical, biological, and physical environmental factors on the alpha cell. Notably, we found studies focusing on the effects of different categories of compounds, including air pollutants, compounds of known toxicity present in common objects, pharmacological agents, and compounds possibly present in food, plus studies on the effects of physical factors (mainly heat exposure). However, the overall number of relevant studies was limited, especially when compared to studies related to the environment and insulin sensitivity or beta-cell function. In our opinion, this was likely due to the underestimation of the alpha-cell role in glucose homeostasis, but since such a role has recently emerged with increasing strength, we expect several new studies about the environment and alpha-cell in the near future.

Contribution of rare variants in monogenic diabetes-genes to early-onset type 2 diabetes.

AIM: This study investigated whether rare, deleterious variants in monogenic diabetes-genes are associated with early-onset type 2 diabetes (T2D). METHODS: A nested case-control study was designed from 9712 Italian patients with T2D. Individuals with age at diabetes onset ≤35 yrs (n = 300; cases) or ≥65 yrs (n = 300; controls) were selected and screened for variants in 27 monogenic diabetes-genes by targeted resequencing. Rare (minor allele frequency-MAF <1%) and possibly deleterious variants were collectively tested for association with early-onset T2D. The association of a genetic risk score (GRS) based on 17 GWAS-SNPs for T2D was also tested. RESULTS: When all rare variants were considered together, each increased the risk of early-onset T2D by 65% (allelic OR =1.64, 95% CI: 1.08-2.48, p = 0.02). Effects were similar when the 600 study participants were stratified according to their place of recruitment (Central-Southern Italy, 182 cases vs. 142 controls, or Rome urban area, 118 vs. 158, p for heterogeneity=0.53). Progressively less frequent variants showed increasingly stronger effects in the risk of early-onset T2D for those with MAF <0.001% (OR=6.34, 95% CI: 1.87-22.43, p = 0.003). One unit of T2D-GRS significantly increased the risk of early-onset T2D (OR 1.09, 95% CI: 1.01-1.18; p = 0.02). This association was stronger among rare variants carriers as compared to non-carriers (p = 0.02). CONCLUSION: Rare variants in monogenic-diabetes genes are associated with an increased risk of early-onset T2D, and interact with common T2D susceptibility variants in shaping it. These findings might help develop prediction tools to identify individuals at high risk of developing T2D in early adulthood.

Oxidative Stress and Left Ventricular Performance in Patients with Different Glycometabolic Phenotypes.

The aim of the present study was to evaluate the possible correlation between oxidative stress and subclinical myocardial damage, assessed with speckle tracking echocardiography (STE), in normal glucose tolerance (NGT) patients with one-hour plasma glucose values ≥ 155 mg/dL (NGT ≥ 155), comparing them to NGT < 155 subjects, impaired glucose tolerance (IGT) and type 2 diabetes mellitus (T2DM) newly diagnosed patients. We enrolled 100 Caucasian patients. All subjects underwent OGTT. The serum values of oxidative stress markers (8-isoprostane and Nox-2) were assessed with an ELISA test. Echocardiographic recordings were performed using an E-95 Pro ultrasound system. We observed significant differences, among the four groups, for fasting plasma glucose (p < 0.0001), one-hour postload (p < 0.0001), and two-hour postload plasma glucose (p < 0.0001). As compared with NGT < 155, NGT ≥ 155 exhibited significantly worse insulin sensitivity and higher values of hs-CRP. No significant differences were observed between NGT ≥ 155 and IGT patients. There was a significant increase in 8-isoprostane (p < 0.0001) and Nox-2 (p < 0.0001), from the first to fourth group, indicating an increase in oxidative stress with the worsening of the metabolic status. Serum levels of 8-isoprostane and Nox-2 were significantly increased in NGT ≥ 155 compared to the NGT < 155 group, but similar to IGT. The global longitudinal strain (GLS) appeared progressively lower proceeding from the NGT < 155 to T2DM group (p < 0.0001). For similar values of left ventricular ejection fraction (LVEF), NGT ≥ 155 exhibited reduced GLS compared to NGT < 155 (p = 0.001), but similar to IGT patients. Our study demonstrated that NGT ≥ 155 subjects exhibit early functional impairment of myocardial contractile fibres, these alterations are correlated with increased oxidative stress.

The Triglycerides and Glucose (TyG) Index Is Associated with 1-Hour Glucose Levels during an OGTT.

BACKGROUND AND OBJECTIVES: Among individuals with normal glucose tolerance (NGT), subjects with high levels of plasma glucose (≥155 mg/dL) at sixty minutes during an oral glucose tolerance test (1h-OGTT) are at an increased risk of developing type 2 diabetes. We investigated the association between the triglycerides and glucose (TyG) index, a novel marker of insulin resistance, with 1h-OGTT glucose plasma concentrations. MATERIAL AND METHODS: 1474 non-diabetic Caucasian subjects underwent a 75 g OGTT and were divided into two groups according to the cutoff 1h-OGTT plasma glucose < 155 mg/dL (NGT-1h-low) and ≥ 155 mg/dL (NGT-1h-high). The TyG index was calculated as ln [fasting triglycerides (milligrams per deciliter) × fasting blood glucose (milligrams per deciliter)/2]. Multivariable linear and logistic regression analyses were used to establish the contribution of the TyG index to the variability of 1h-OGTT glucose, and how the former affected the risk of being NGT-1h-high. RESULTS: 1004 individuals were NGT-1h-low and 470 were NGT-1h-high. The TyG index was higher for NGT-1h-high (p = 0.001) individuals, and it was an independent factor influencing 1h-OGTT glycemia (ß = 0.191, p < 0.001) after correcting for age, sex, and BMI. The TyG index was the strongest marker associated with the risk of being NGT-1h-high (OR = 1.703, CI 95% 1.34-2.17, p < 0.001) when compared with FPG (OR = 1.054, CI 95% 1.04-1.07, p < 0.001) and the HOMA-IR (OR = 1.156, CI 95% 1.08-1.23, p < 0.001). CONCLUSIONS: Our study demonstrated that the TyG index, an efficient and cost-effective marker of insulin resistance, is associated with the variability of early post-challenge glucose levels and is an independent marker of being NGT-1h-high.

Vitamin D Serum Levels in Subjects Tested for SARS-CoV-2: What Are the Differences among Acute, Healed, and Negative COVID-19 Patients? A Multicenter Real-Practice Study.

Vitamin D might play a role in counteracting COVID-19, albeit strong evidence is still lacking in the literature. The present multicenter real-practice study aimed to evaluate the differences of 25(OH)D3 serum levels in adults tested for SARS-CoV-2 (acute COVID-19 patients, subjects healed from COVID-19, and non-infected ones) recruited over a 6-month period (March-September 2021). In a sample of 117 subjects, a statistically significant difference was found, with acute COVID-19 patients demonstrating the lowest levels of serum 25(OH)D3 (9.63 ± 8.70 ng/mL), significantly lower than values reported by no-COVID-19 patients (15.96 ± 5.99 ng/mL, p = 0.0091) and healed COVID-19 patients (11.52 ± 4.90 ng/mL, p > 0.05). Male gender across the three groups displayed unfluctuating 25(OH)D3 levels, hinting at an inability to ensure adequate levels of the active vitamin D3 form (1α,25(OH)2D3). As a secondary endpoint, we assessed the correlation between serum 25(OH)D3 levels and pro-inflammatory cytokine interleukin-6 (IL-6) in patients with extremely low serum 25(OH)D3 levels (<1 ng/mL) and in a subset supplemented with 1α,25(OH)2D3. Although patients with severe hypovitaminosis-D showed no significant increase in IL-6 levels, acute COVID-19 patients manifested high circulating IL-6 at admission (females = 127.64 ± 22.24 pg/mL, males = 139.28 ± 48.95 ng/mL) which dropped drastically after the administration of 1α,25(OH)2D3 (1.84 ± 0.77 pg/mL and 2.65 ± 0.92 ng/mL, respectively). Taken together, these findings suggest that an administration of 1α,25(OH)2D3 might be helpful for treating male patients with an acute COVID-19 infection. Further studies on rapid correction of vitamin D deficiency with fast acting metabolites are warranted in COVID-19 patients.

Metabolites Profiling of Melanoma Interstitial Fluids Reveals Uridine Diphosphate as Potent Immune Modulator Capable of Limiting Tumor Growth.

Tumor interstitial fluid (TIF) surrounds and perfuses tumors and collects ions, metabolites, proteins, and extracellular vesicles secreted by tumor and stromal cells. Specific metabolites, accumulated within the TIF, could induce metabolic alterations of immune cells and shape the tumor microenvironment. We deployed a metabolomic approach to analyze the composition of melanoma TIF and compared it to the plasma of C57BL6 mice, engrafted or not with B16-melanoma cells. Among the classes of metabolites analyzed, monophosphate and diphosphate nucleotides resulted enriched in TIF compared to plasma samples. The analysis of the effects exerted by guanosine diphosphate (GDP) and uridine diphosphate (UDP) on immune response revealed that GDP and UDP increased the percentage of CD4+CD25+FoxP3- and, on isolated CD4+ T-cells, induced the phosphorylation of ERK, STAT1, and STAT3; increased the activity of NF-κB subunits p65, p50, RelB, and p52; increased the expression of Th1/Th17 markers including IFNγ, IL17, T-bet, and RORγt; and reduced the expression of IL13, a Th2 marker. Finally, we observed that local administrations of UDP in B16-engrafted C57BL6 mice reduced tumor growth and necrotic areas. In addition, UDP-treated tumors showed a higher presence of MHCIIhi tumor-associated macrophage (TAM) and of CD3+CD8+ and CD3+CD4+ tumor-infiltrating T-lymphocytes (TILs), both markers of anti-tumor immune response. Consistent with this, intra-tumoral gene expression analysis revealed in UDP-treated tumors an increase in the expression of genes functionally linked to anti-tumor immune response. Our analysis revealed an important metabolite acting as mediator of immune response, which could potentially represent an additional tool to be used as an adjuvant in cancer immunotherapy.

Neutrophil degranulation biomarkers characterize restrictive echocardiographic pattern with diastolic dysfunction in patients with diabetes.

OBJECTIVE: To investigate the potential association between neutrophil degranulation and patterns of myocardial dysfunction in a cohort of patients with type 2 diabetes mellitus (T2DM). BACKGROUND: Two distinct phenotypes of diabetic cardiomyopathy have been described: a restrictive phenotype with diastolic dysfunction (restrictive/DD) and a dilative phenotype with systolic dysfunction (dilative/SD). However, the underlying determinants of these two patterns are not yet recognized. METHODS: In this single-centre, observational, cross-sectional study, 492 patients were recruited. Ultrasonographic measurements were performed by two experienced sonographers, blinded to the clinical data of the participants. Serum biomarkers of neutrophil degranulation were measured by enzyme-linked immunosorbent sandwich assay (ELISA). RESULTS: After adjustment for confounders, resistin, myeloperoxidase, matrix metalloproteinase 8 and matrix metalloproteinase 9/tissue inhibitor of metalloproteinases 1 complex were positively associated with the restrictive/DD pattern compared with the normal pattern. Similarly, MPO was positively associated with the dilative/SD pattern compared with the normal pattern, and resistin was negatively associated with the dilative/SD pattern compared with the restrictive/DD pattern. CONCLUSIONS: Neutrophil degranulation is associated with the restrictive/DD echocardiographic pattern in patients with T2DM, but not with the normal pattern and dilative/SD patterns. Neutrophils could have a pivotal role in the pathogenesis of myocardial dysfunction, and particularly diastolic dysfunction, in patients with T2DM.