Physicians' misperceived cardiovascular risk and therapeutic inertia as determinants of low LDL-cholesterol targets achievement in diabetes

Greater efforts are needed to overcome the worldwide reported low achievement of LDL-c targets. This survey aimed to dissect whether and how the physician-based evaluation of patients with diabetes is associated with the achievement of LDL-c targets

Metformin Benefits: Another Example for Alternative Energy Substrate Mechanism?

Since the UK Prospective Diabetes Study (UKPDS), metformin has been considered the first-line medication for patients with newly diagnosed type 2 diabetes. Though direct evidence from specific trials is still lacking, several studies have suggested that metformin may protect from diabetes- and nondiabetes-related comorbidities, including cardiovascular, renal, neurological, and neoplastic diseases. In the past few decades, several mechanisms of action have been proposed to explain metformin's protective effects, none being final. It is certain, however, that metformin increases lactate production, concentration, and, possibly, oxidation. Once considered a mere waste product of exercising skeletal muscle or anaerobiosis, lactate is now known to act as a major energy shuttle, redistributed from production sites to where it is needed. Through the direct uptake and oxidation of lactate produced elsewhere, all end organs can be rapidly supplied with fundamental energy, skipping glycolysis and its possible byproducts. Increased lactate production (and consequent oxidation) could therefore be considered a positive mechanism of action of metformin, except when, under specific circumstances, metformin and lactate become excessive, increasing the risk of lactic acidosis. We are proposing that, rather than considering metformin-induced lactate production as dangerous, it could be considered a mechanism through which metformin exerts its possible protective effect on the heart, kidneys, and brain and, to some extent, its antineoplastic action

Use and effectiveness of dapagliflozin in routine clinical practice. An Italian multicenter retrospective study

In randomized controlled trials (RCTs), SGLT-2 inhibitors (SGLT2i) showed glycaemic and extra-glycaemic benefits. The DARWIN-T2D (DApagliflozin Real World evIdeNce in Type 2 Diabetes) was a multicenter retrospective study designed to evaluate baseline characteristics of patients receiving dapagliflozin versus selected comparators (DPP-4 inhibitors, gliclazide, or GLP-1 receptor agonists), and drug effectiveness in routine clinical practice. From a population of 281,217 patients, the analysis included 17,285 initiating dapagliflozin or comparator glucose lowering medications (GLM), 6751 of whom had a follow-up examination. At baseline, patients starting dapagliflozin were younger, had a longer disease duration, higher HbA1c, and a more complex history of previous GLM use, but the clinical profile of patients receiving dapagliflozin was changing during the study period. Dapagliflozin reduced HbA1c by 0.7%, body weight by 2.7 kg, and systolic blood pressure by 3.0 mm Hg. Effects of comparator GLM were also within the expected range based on RCTs. This real-world study demonstrates an initial channelling of dapagliflozin to difficult-to-treat patients. Nonetheless, dapagliflozin provided significant benefits on glucose control, body weight, and blood pressure that were in line with findings from RCTs

Identification of two novel LDLR variants by Next Generation Sequencing

Introduction. Familial hypercholesterolemia (FH) is an autosomal dominant inherited disease characterized by elevated plasma low-density lipoprotein cholesterol (LDL-C). Targeted Next Generation Sequencing (NGS) is a new opportunity to expand the existing pathogenic variants (PVs) spectrum associated to FH. Our aim was to report a diagnostic NGS-based approach to detect variants associated to FH.Methods. We report two patients: a 48-year-old Asian woman, without known history of hypercholesterolemia and a 46-year-old Caucasian man, with childhood hypercholesterolemia.Results. An effective NGS-based pipeline, FH-Devyser kit/Amplicon Suite, beginning from sequencing to data analysis, did not identify known PVs in the LDLR, APOB, APOE, LDLRAP1, STAP1 and PCSK9 genes, but revealed two novel LDLR variants (c.1564A>T, p.Ile522Phe and c.1688C>T, p.Pro563Leu).Discussion and conclusions. This study showed that an effective NGS-based pipeline led to a definitive diagnosis in two FH families, allowing to plan their therapeutic treatment. Although the functional consequence of the two LDLR variants needs to be assessed in vitro, the in silico analysis and high preservation of the two amino acid positions observed in the LDLR protein, across different animal species, suggest that both variants are deleterious

High-normal TSH values in obesity: is it insulin resistance or adipose tissue's guilt?

Objective: Clinical evidences reported subclinical alterations of thyroid function in obesity, although the relationship between thyroid status and obesity remains unclear. We cross-sectionally investigated the influence of metabolic features on hypothalamic-pituitary-thyroid axis in obesity. Design and methods: We enrolled 60 euthyroid subjects with no history of type 2 diabetes mellitus and assessed the relationship of thyroid function with insulin resistance, measured using euglycemic clamp, and abdominal fat volume, quantified by computed tomography scan (CT scan). Thyroid stimulating hormone (TSH) correlated with BMI (r = 0.46; P = 0.02), both visceral (r = 0.58; P = 0.02) and subcutaneous adipose tissue volumes (r = 0.43; P = 0.03) and insulin resistance (inverse relationship with insulin sensitivity-glucose uptake: r = -0.40; P = 0.04). Results: After performing multivariate regression, visceral adipose tissue volume was found to be the most powerful predictor of TSH (β = 3.05; P = 0.01), whereas glucose uptake, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, subcutaneous adipose tissue volume, and triglycerides were not. To further confirm the hypothesis that high-normal TSH values could be dependent on adipose tissue, and not on insulin resistance, we restricted our analyses to moderately obese subjects' BMI ranging 30-35 kg/m(2). This subgroup was then divided as insulin resistant and insulin sensitive according to the glucose uptake (≤ or >5 mg · kg(-1) · min(-1), respectively). We did not find any statistical difference in TSH (insulin resistant: 1.62 ± 0.65 µU/ml vs. insulin sensitive: 1.46 ± 0.48; P = not significant) and BMI (insulin resistant: 32.2 ± 1.6 kg/m(2) vs. insulin sensitive: 32.4 ± 1.4; P = not significant), thus confirming absence of correlation between thyroid function and insulin sensitivity per se. Conclusion: Our study suggests that the increase in visceral adipose tissue is the best predictor of TSH concentration in obesity, independently from the eventual concurrent presence of insulin resistance

All-cause mortality and cardiovascular events in patients with type 2 diabetes treated with alpha-glucosidase inhibitors: A meta-analysis of randomized controlled trials

Aim: Alpha-glucosidase inhibitors are approved drugs for treating type 2 diabetes (T2DM); however, their effects on mortality and cardiovascular safety are unclear. This metaanalysis was aimed at evaluating the effects of alpha-glucosidase inhibitors on all-cause mortality and major cardiovascular events (MACE). Data synthesis: A Medline, Embase, Cochrane database searching for alpha-glucosidase inhibitors was performed up to July 1st, 2021. All randomized controlled trials (RCT) with a duration >52 weeks and comparing the effects of alpha-glucosidase inhibitors with placebo or active drugs were collected. Further inclusion criteria were: RCT reporting MACE within their primary outcome, or as pre-defined secondary outcome; and RCT enrolling at least 100 patients with T2DM. Mantel-Haenszel odds ratio (MH-OR) with 95% confidence intervals were calculated for the aforementioned outcomes. A total of eight RCTs, enrolling 1124 and 908 patients on alpha-glucosidase inhibitors and comparators, respectively, were identified. No trials reported information on MACE. Treatment with alpha-glucosidase inhibitors was not associated with a significant increase of all-cause mortality compared with other therapies or no therapy/placebo Conclusions: The evidence of beneficial or detrimental effects of alpha-glucosidase inhibitors on all-cause mortality and cardiovascular events is not sufficient to draw any conclusions. (c) 2021 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved

Cardiovascular events and all-cause mortality in patients with type 2 diabetes treated with dipeptidyl peptidase-4 inhibitors: An extensive meta-analysis of randomized controlled trials

Aims: Meta-analyses of randomized trials on Dipeptidyl Peptidase-4 inhibitors (DPP4i) reported discordant results on major cardiovascular events (MACE), mortality, and heart failure. Aim of this meta-analysis of randomized trials is the assessment of the cardiovascular safety of DPP4i. Data synthesis: A Medline, Embase, Cochrane database search for sitagliptin, vildagliptin, omar-igliptin, saxagliptin, alogliptin, trelagliptin, anagliptin, linagliptin, gemigliptin, evogliptin, and te-neligliptin was performed up to up January 1st, 2020. All trials with a duration >24 weeks and comparing the effects of DPP4i with placebo or active drugs were collected. Mantel-Haenszel odds ratio (MH-OR) with 95% Confidence Interval (95% CI) was calculated for all outcomes defined above. A total of 182 eligible trials were identified. DPP-4i were not associated with an increased risk of MACE (MH-OR 0.99 [0.93, 1.04]), all-cause mortality (MH-OR 0.99 [0.93, 1.06]), and heart failure (MH-OR 1.05 [0.96, 1.15]) with no significant differences across individual molecules, except for saxagliptin, which was associated with an increased risk of heart failure. Conclusions: As a class, DPP4i are not associated with any increase or reduction of MACE, all -cause mortality, and heart failure. Saxagliptin seems to be associated with an increased risk of hospitalization for heart failure

Pancreatic beta-cell IL-22 receptor deficiency induces age-dependent dysregulation of insulin biosynthesis and systemic glucose homeostasis

The IL-22RA1 receptor is highly expressed in the pancreas, and exogenous IL-22 has been shown to reduce endoplasmic reticulum and oxidative stress in human pancreatic islets and promote secretion of high-quality insulin from beta-cells. However, the endogenous role of IL-22RA1 signaling on these cells remains unclear. Here, we show that antibody neutralisation of IL-22RA1 in cultured human islets leads to impaired insulin quality and increased cellular stress. Through the generation of mice lacking IL-22ra1 specifically on pancreatic alpha- or beta-cells, we demonstrate that ablation of murine beta-cell IL-22ra1 leads to similar decreases in insulin secretion, quality and islet regeneration, whilst increasing islet cellular stress, inflammation and MHC II expression. These changes in insulin secretion led to impaired glucose tolerance, a finding more pronounced in female animals compared to males. Our findings attribute a regulatory role for endogenous pancreatic beta-cell IL-22ra1 in insulin secretion, islet regeneration, inflammation/cellular stress and appropriate systemic metabolic regulation.IL-22RA1 is highly expressed on pancreatic islets and absent on immune cells. Here, the authors investigate its role by generating animals that lack IL-22RA1 on beta cells and reveal IL22RA1 signalling is critical for insulin biosynthesis and beta-cell health, evidenced by its regulation of MHC II expression and its suppressive effect on inflammation and cellular stress

IL-21 is a major negative regulator of IRF4-dependent lipolysis affecting Tregs in adipose tissue and systemic insulin sensitivity.

Obesity elicits immune cell infiltration of adipose tissue provoking chronic low-grade inflammation. Regulatory T cells (Tregs) are specifically reduced in adipose tissue of obese animals. Since interleukin (IL)-21 plays an important role in inducing and maintaining immune-mediated chronic inflammatory processes and negatively regulates Treg differentiation/activity, we hypothesized that it could play a role in obesity-induced insulin resistance. We found IL-21 and IL-21R mRNA expression upregulated in adipose tissue of high-fat diet (HFD) wild-type (WT) mice and in stromal vascular fraction from human obese subjects in parallel to macrophage and inflammatory markers. Interestingly, a larger infiltration of Treg cells was seen in the adipose tissue of IL-21 knockout (KO) mice compared with WT animals fed both normal diet and HFD. In a context of diet-induced obesity, IL-21 KO mice, compared with WT animals, exhibited lower body weight, improved insulin sensitivity, and decreased adipose and hepatic inflammation. This metabolic phenotype is accompanied by a higher induction of interferon regulatory factor 4 (IRF4), a transcriptional regulator of fasting lipolysis in adipose tissue. Our data suggest that IL-21 exerts negative regulation on IRF4 and Treg activity, developing and maintaining adipose tissue inflammation in the obesity state