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1.
Diabetologia ; 66(2): 354-366, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36280617

RESUMO

AIMS/HYPOTHESIS: Endoplasmic reticulum (ER) stress and beta cell dedifferentiation both play leading roles in impaired insulin secretion in overt type 2 diabetes. Whether and how these factors are related in the natural history of the disease remains, however, unclear. METHODS: In this study, we analysed pancreas biopsies from a cohort of metabolically characterised living donors to identify defects in in situ insulin synthesis and intra-islet expression of ER stress and beta cell phenotype markers. RESULTS: We provide evidence that in situ altered insulin processing is closely connected to in vivo worsening of beta cell function. Further, activation of ER stress genes reflects the alteration of insulin processing in situ. Using a combination of 17 different markers, we characterised individual pancreatic islets from normal glucose tolerant, impaired glucose tolerant and type 2 diabetic participants and reconstructed disease progression. CONCLUSIONS/INTERPRETATION: Our study suggests that increased beta cell workload is accompanied by a progressive increase in ER stress with defects in insulin synthesis and loss of beta cell identity.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Ilhotas Pancreáticas , Humanos , Insulina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Estresse do Retículo Endoplasmático/genética , Glucose/metabolismo
2.
Cardiovasc Diabetol ; 22(1): 349, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38115004

RESUMO

OBJECTIVE: We recently demonstrated that treatment with sodium-glucose cotransporter-2 inhibitors (SGLT-2i) leads to an increase in myocardial flow reserve in patients with type 2 diabetes (T2D) with stable coronary artery disease (CAD). The mechanism by which this occurs is, however, unclear. One of the risk factors for cardiovascular disease is inflammation of epicardial adipose tissue (EAT). Since the latter is often increased in type 2 diabetes patients, it could play a role in coronary microvascular dysfunction. It is also well known that SGLT-2i modify adipose tissue metabolism. We aimed to investigate the effects of the SGLT-2i dapagliflozin on metabolism and visceral and subcutaneous adipose tissue thickness in T2D patients with stable coronary artery disease and to verify whether these changes could explain observed changes in myocardial flow. METHODS: We performed a single-center, prospective, randomized, double-blind, controlled clinical trial with 14 T2D patients randomized 1:1 to SGLT-2i dapagliflozin (10 mg daily) or placebo. The thickness of visceral (epicardial, mediastinal, perirenal) and subcutaneous adipose tissue and glucose uptake were assessed at baseline and 4 weeks after treatment initiation by 2-deoxy-2-[18F]fluoro-D-glucose Positron Emission Tomography/Computed Tomography during hyperinsulinemic euglycemic clamp. RESULTS: The two groups were well-matched for baseline characteristics (age, diabetes duration, HbA1c, BMI, renal and heart function). Dapagliflozin treatment significantly reduced EAT thickness by 19% (p = 0.03). There was a significant 21.6% reduction in EAT glucose uptake during euglycemic hyperinsulinemic clamp in the dapagliflozin group compared with the placebo group (p = 0.014). There were no significant effects on adipose tissue thickness/metabolism in the other depots explored. CONCLUSIONS: SGLT-2 inhibition selectively reduces EAT thickness and EAT glucose uptake in T2D patients, suggesting a reduction of EAT inflammation. This could explain the observed increase in myocardial flow reserve, providing new insights into SGLT-2i cardiovascular benefits.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Tecido Adiposo/metabolismo , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/tratamento farmacológico , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Tecido Adiposo Epicárdico , Glucose/metabolismo , Inflamação/tratamento farmacológico , Estudos Prospectivos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico
3.
Diabetes Metab Res Rev ; 39(7): e3668, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37309298

RESUMO

Non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2D) are metabolic disorders connected by common pathophysiological mechanisms. Since insulin resistance (IR) and metabolic alterations are common to both conditions, almost all glucose-lowering agents which improve IR have also been studied in patients with NAFLD. Some have shown great efficacy, others none. Thus, the mechanisms behind the efficacy of these drugs in improving hepatic steatosis, steatohepatitis, and eventually fibrosis remain controversial. Glycaemic control improves T2D, but probably has limited effects on NAFLD, as all glucose-lowering agents ameliorate glucose control but only a few improve NAFLD features. In contrast, drugs that either improve adipose tissue function, reduce lipid ingestion, or increase lipid oxidation are particularly effective in NAFLD. We therefore hypothesise that improved free fatty acid metabolism may be the unifying mechanism behind the efficacy of some glucose-lowering agents on NAFLD and may represent the key to NAFLD treatment.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Glucose/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Lipídeos , Fígado
4.
Cardiovasc Diabetol ; 21(1): 173, 2022 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-36057768

RESUMO

OBJECTIVE: Cardiovascular (CV) outcome trials have shown that in patients with type 2 diabetes (T2D), treatment with sodium-glucose cotransporter-2 inhibitors (SGLT-2i) reduces CV mortality and hospital admission rates for heart failure (HF). However, the mechanisms behind these benefits are not fully understood. This study was performed to investigate the effects of the SGLT-2i dapagliflozin on myocardial perfusion and glucose metabolism in patients with T2D and stable coronary artery disease (coronary stenosis ≥ 30% and < 80%), with or without previous percutaneous coronary intervention (> 6 months) but no HF. METHODS: This was a single-center, prospective, randomized, double-blind, controlled clinical trial including 16 patients with T2D randomized to SGLT-2i dapagliflozin (10 mg daily) or placebo. The primary outcome was to detect changes in myocardial glucose uptake (MGU) from baseline to 4 weeks after treatment initiation by [(18)F]2-deoxy-2-fluoro-D-glucose (FDG) PET/CT during hyperinsulinemic euglycemic clamp. The main secondary outcome was to assess whether the hypothetical changes in MGU were associated with changes in myocardial blood flow (MBF) and myocardial flow reserve (MFR) measured by 13N-ammonia PET/CT. The study was registered at eudract.ema.europa.eu (EudraCT No. 2016-003614-27) and ClinicalTrials.gov (NCT03313752). RESULTS: 16 patients were randomized to dapagliflozin (n = 8) or placebo (n = 8). The groups were well-matched for baseline characteristics (age, diabetes duration, HbA1c, renal and heart function). There was no significant change in MGU during euglycemic hyperinsulinemic clamp in the dapagliflozin group (2.22 ± 0.59 vs 1.92 ± 0.42 µmol/100 g/min, p = 0.41) compared with the placebo group (2.00 ± 0.55 vs 1.60 ± 0.45 µmol/100 g/min, p = 0.5). Dapagliflozin significantly improved MFR (2.56 ± 0.26 vs 3.59 ± 0.35 p = 0.006 compared with the placebo group 2.34 ± 0.21 vs 2.38 ± 0.24 p = 0.81; pint = 0.001) associated with a reduction in resting MBF corrected for cardiac workload (p = 0.005; pint = 0.045). A trend toward an increase in stress MBF was also detected (p = 0.054). CONCLUSIONS: SGLT-2 inhibition increases MFR in T2D patients. We provide new insight into SGLT-2i CV benefits, as our data show that patients on SGLT-2i are more resistant to the detrimental effects of obstructive coronary atherosclerosis due to increased MFR, probably caused by an improvement in coronary microvascular dysfunction. Trial registration EudraCT No. 2016-003614-27; ClinicalTrials.gov Identifier: NCT03313752.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Inibidores do Transportador 2 de Sódio-Glicose , Compostos Benzidrílicos , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosídeos , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Prospectivos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos
5.
Cardiovasc Diabetol ; 18(1): 20, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30819210

RESUMO

Sotagliflozin is a dual sodium-glucose co-transporter-2 and 1 (SGLT2/1) inhibitor for the treatment of both type 1 (T1D) and type 2 diabetes (T2D). Sotagliflozin inhibits renal sodium-glucose co-transporter 2 (determining significant excretion of glucose in the urine, in the same way as other, already available SGLT-2 selective inhibitors) and intestinal SGLT-1, delaying glucose absorption and therefore reducing post prandial glucose. Well-designed clinical trials, have shown that sotagliflozin (as monotherapy or add-on therapy to other anti-hyperglycemic agents) improves glycated hemoglobin in adults with T2D, with beneficial effects on bodyweight and blood pressure. Similar results have been obtained in adults with T1D treated with either continuous subcutaneous insulin infusion or multiple daily insulin injections, even after insulin optimization. A still ongoing phase 3 study is currently evaluating the effect of sotagliflozin on cardiovascular outcomes (ClinicalTrials.gov NCT03315143). In this review we illustrate the advantages and disadvantages of dual SGLT 2/1 inhibition, in order to better characterize and investigate its mechanisms of action and potentialities.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glicosídeos/uso terapêutico , Rim/efeitos dos fármacos , Transportador 1 de Glucose-Sódio/antagonistas & inibidores , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Transportador 2 de Glucose-Sódio/efeitos dos fármacos , Animais , Biomarcadores/sangue , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Quimioterapia Combinada , Glicosídeos/efeitos adversos , Humanos , Rim/metabolismo , Transportador 1 de Glucose-Sódio/metabolismo , Transportador 2 de Glucose-Sódio/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Resultado do Tratamento
6.
Mediators Inflamm ; 2019: 9367404, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32082078

RESUMO

Diabetes is not a single and homogeneous disease, but a cluster of metabolic diseases characterized by the common feature of hyperglycemia. The pathogenesis of type 1 diabetes (T1D) and type 2 diabetes (T2D) (and all other intermediate forms of diabetes) involves the immune system, in terms of inflammation and autoimmunity. The past decades have seen an increase in all types of diabetes, accompanied by changes in eating habits and consequently a structural evolution of gut microbiota. It is likely that all these events could be related and that gut microbiota alterations might be involved in the immunomodulation of diabetes. Thus, gut microbiota seems to have a direct, even causative role in mediating connections between the environment, food intake, and chronic disease. As many conditions that increase the risk of diabetes modulate gut microbiota composition, it is likely that immune-mediated reactions, induced by alterations in the composition of the microbiota, can act as facilitators for the onset of diabetes in predisposed subjects. In this review, we summarize recent evidence in the field of gut microbiota and the role of the latter in modulating the immune reactions involved in the pathogenesis of diabetes.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Microbioma Gastrointestinal/fisiologia , Sistema Imunitário/metabolismo , Animais , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 2/imunologia , Microbioma Gastrointestinal/imunologia , Humanos , Sistema Imunitário/imunologia
7.
Endocr Pract ; 24(5): 419-428, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29847168

RESUMO

OBJECTIVE: The adherence by endocrinologists to guideline regarding levothyroxine (LT4) therapy and the compliance of patients may impact the management of hypothyroidism. The aim of this study was to compare the adherence of Italian endocrinologists to the ATA/AACE and ETA guidelines on the management of newly diagnosed primary hypothyroidism and to validate the Italian version of the Morisky-Green Medical Adherence Scale-8 (MMAS-8) questionnaire as applied to the evaluation of the adherence of patients with hypothyroidism to LT4 treatment. METHODS: This was an observational, longitudinal, multicenter, cohort study, involving 12 Italian Units of Endocrinology. RESULTS: The study enrolled 1,039 consecutive outpatients (mean age 48 years; 855 women, 184 men). The concordance of Italian endocrinologists with American Association of Clinical Endocrinologists/American Thyroid Association (AACE/ATA) and European Thyroid Association (ETA) recommendations was comparable (77.1% and 71.7%) and increased (86.7 and 88.6%) after the recommendations on LT4 dose were excluded, considering only the remaining recommendations on diagnosis, therapy, and follow-up. The MMAS-8 was filled out by 293 patients. The mean score was 6.71 with 23.9% low (score <6), 38.6% medium (6 to <8), 37.5% highly (= 8) adherers; the internal validation coefficient was 0.613. Highly adherent patients were not more likely to have good control of hypothyroidism compared with either medium (69% versus 72%, P = .878) or low (69% versus 43%, P = .861) adherers. CONCLUSION: Clinical management of hypothyroidism in Italy demonstrated an observance of international guidelines by Italian endocrinologists. Validation of the Italian version of the MMAS-8 questionnaire provides clinicians with a reliable and simple tool for assessing the adherence of patients to LT4 treatment. ABBREVIATIONS: AACE = American Association of Clinical Endocrinologists; ATA = American Thyroid Association; EDIPO = Endotrial SIE: DIagnosis and clinical management of Primitive hypothyrOidism in Italy; eCRF = electronic case report form; ETA = European Thyroid Association; fT3 = free triiodothyronine; fT4 = free thyroxine; LT4 = levothyroxine; MMAS-8 = Morisky-Green Medical Adherence Scale-8; PH = primary hypothyroidism; T3 = triiodothyronine; T4 = thyroxine; TSH = thyroid-stimulating hormone; US = ultrasonography.


Assuntos
Endocrinologistas/normas , Fidelidade a Diretrizes/estatística & dados numéricos , Hipotireoidismo/tratamento farmacológico , Padrões de Prática Médica/normas , Tiroxina/uso terapêutico , Adulto , Estudos de Coortes , Feminino , Humanos , Itália , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto
8.
Int J Mol Sci ; 17(11)2016 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-27827997

RESUMO

Genetic variants in the fat mass- and obesity-associated gene Fto are linked to the onset of obesity in humans. The causal role of the FTO protein in obesity is supported by evidence obtained from transgenic mice; however, the underlying molecular pathways pertaining to the role of FTO in obesity have yet to be established. In this study, we investigate the Fto gene in mouse brown adipose tissue and in the browning process of white adipose tissue. We analyze distinct structural and molecular factors in brown and white fat depots of Fto-deficient mice under normal and obesogenic conditions. We report significant alterations in the morphology of adipose tissue depots and the expression of mRNA and microRNA related to brown adipogenesis and metabolism in Fto-deficient mice. Furthermore, we show that high-fat feeding does not attenuate the browning process of Fto-deficient white adipose tissue as observed in wild-type tissue, suggesting a triggering effect of the FTO pathways by the dietary environment.


Assuntos
Adipogenia/genética , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , MicroRNAs/genética , Obesidade/genética , Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/patologia , Dioxigenase FTO Dependente de alfa-Cetoglutarato/deficiência , Animais , Biomarcadores/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dieta Hiperlipídica , Metabolismo Energético/genética , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Knockout , MicroRNAs/metabolismo , Obesidade/etiologia , Obesidade/metabolismo , Obesidade/patologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Adrenérgicos beta 3/genética , Receptores Adrenérgicos beta 3/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
9.
FASEB J ; 28(8): 3745-57, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24806198

RESUMO

The mineralocorticoid receptor (MR) controls adipocyte function, but its role in the conversion of white adipose tissue (WAT) into thermogenic fat has not been elucidated. We investigated responses to the MR antagonists spironolactone (spiro; 20 mg/kg/d) and drospirenone (DRSP; 6 mg/kg/d) in C57BL/6 mice fed a high-fat (HF) diet for 90 d. DRSP and spiro curbed HF diet-induced impairment in glucose tolerance, and prevented body weight gain and white fat expansion. Notably, either MR antagonist induced up-regulation of brown adipocyte-specific transcripts and markedly increased protein levels of uncoupling protein 1 (UCP1) in visceral and inguinal fat depots when compared with the HF diet group. Positron emission tomography and magnetic resonance spectroscopy confirmed acquisition of brown fat features in WAT. Interestingly, MR antagonists markedly reduced the autophagic rate both in murine preadipocytes in vitro (10(-5) M) and in WAT depots in vivo, with a concomitant increase in UCP1 protein expression. Moreover, the autophagy repressor bafilomycin A1 (10(-8) M) mimicked the effect of MR antagonists, increasing UCP1 protein expression in primary preadipocytes. Hence, we showed that adipocyte MR regulates brown remodeling of WAT through a modulation of autophagy. These results provide a rationale for the use of MR antagonists to prevent the adverse metabolic consequences of adipocyte dysfunction.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Androstenos/farmacologia , Autofagia/efeitos dos fármacos , Transdiferenciação Celular/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Intolerância à Glucose/prevenção & controle , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Receptores de Mineralocorticoides/fisiologia , Espironolactona/farmacologia , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Adipogenia/fisiologia , Aldosterona/farmacologia , Androstenos/uso terapêutico , Animais , Composição Corporal/efeitos dos fármacos , Células Cultivadas , Feminino , Perfilação da Expressão Gênica , Intolerância à Glucose/etiologia , Canal Inguinal , Gordura Intra-Abdominal/efeitos dos fármacos , Canais Iônicos/biossíntese , Canais Iônicos/genética , Macrolídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Proteínas Mitocondriais/biossíntese , Proteínas Mitocondriais/genética , Obesidade/tratamento farmacológico , Obesidade/fisiopatologia , Obesidade/prevenção & controle , Receptores de Mineralocorticoides/efeitos dos fármacos , Espironolactona/uso terapêutico , Proteína Desacopladora 1 , Regulação para Cima/efeitos dos fármacos , Aumento de Peso/efeitos dos fármacos
10.
Hormones (Athens) ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748060

RESUMO

The aim of this review is to discuss the several interconnections between thyroid autoimmunity and type 1 diabetes in terms of epidemiology, immunoserology, genetic predisposition, and pathogenic mechanisms. We will also analyze the impact of these conditions on both male and female fertility. A literature search was carried out using the MEDLINE/PubMed, Scopus, Google Scholar, ResearchGate, and Clinical Trials Registry databases with a combination of keywords. It was found that the prevalence of thyroid autoantibodies in individuals with type 1 diabetes (T1DM) varied in different countries and ethnic groups from 7 to 35% in both sexes. There are several types of autoantibodies responsible for the immunoserological presentation of autoimmune thyroid diseases (AITDs) which can be either stimulating or inhibiting, which results in AITD being in the plus phase (thyrotoxicosis) or the minus phase (hypothyroidism). Different types of immune cells such as T cells, B cells, natural killer (NK) cells, antigen presenting cells (APCs), and other innate immune cells participate in the damage of the beta cells of the islets of Langerhans, which inevitably leads to T1D. Multiple genetic and environmental factors found in variable combinations are involved in the pathogenesis of AITD and T1D. In conclusion, although it is now well-known that both diabetes and thyroid diseases can affect fertility, only a few data are available on possible effects of autoimmune conditions. Recent findings nevertheless point to the importance of screening patients with immunologic infertility for AITDs and T1D, and vice versa.

11.
Diabetes Ther ; 15(1): 257-268, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37883003

RESUMO

BACKGROUND: Sodium-glucose cotransporter-2 (SGLT2) inhibitors have shown controversial results in modulating plasma lipids in clinical trials. Most studies found slight increases in high-density lipoprotein (HDL) cholesterol but few have provided evidence on HDL functionality with disappointing results. However, there is broad agreement that these drugs provide cardiovascular protection through several mechanisms. Our group demonstrated that dapagliflozin improves myocardial flow reserve (MFR) in patients with type 2 diabetes (T2D) with coronary artery disease (CAD). The underlying mechanisms are still unknown, although in vitro studies have suggested the involvement of nitric oxide (NO). AIM: To investigate changes in HDL-mediated modulation of NO production with dapagliflozin and whether there is an association with MFR. METHODS: Sixteen patients with CAD-T2D were enrolled and randomized 1:1 to dapagliflozin or placebo for 4 weeks. Blood samples were collected before and after treatment for each group. The ability of HDL to stimulate NO production in endothelial cells was tested in vitro by incubating human umbilical vein endothelial cells (HUVEC) with apoB-depleted (apoB-D) serum of these patients. The production of NO was assessed by fluorescent assay, and results were expressed as fold versus untreated cells. RESULTS: Change in HDL-mediated NO production remained similar in dapagliflozin and placebo group, even after adjustment for confounders. There were no significant correlations between HDL-mediated NO production and MFR either at baseline or after treatment. No changes were found in HDL cholesterol in either group, while low-density lipoprotein cholesterol (LDL cholesterol) significantly decreased compared to baseline only in treatment group (p = 0.043). CONCLUSIONS: In patients with T2D-CAD, beneficial effects of dapagliflozin on coronary microcirculation seem to be unrelated to HDL functions. However, HDL capacity to stimulate NO production is not impaired at baseline; thus, the effect of drug treatments would be negligible. To conclude, we can assume that HDL-independent molecular pathways are involved in the improvement of MFR in this population. TRIAL REGISTRATION: EudraCT No. 2016-003614-27; ClinicalTrials.gov Identifier: NCT03313752.

12.
Eur J Intern Med ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38871564

RESUMO

AIMS: Chronic pancreatitis (CP) is - along with acute pancreatitis - the most frequent cause of diabetes of the exocrine pancreas (DEP). Although insulin deficiency is widely accepted as the major feature of DEP, it is still unclear whether diabetes associated with CP is characterized by additional or different functional defects of the insulin secretory machinery. To identify possible functional defects specifically induced by CP, we performed a cross-sectional study in individuals with normal glucose tolerance (NGT), impaired glucose tolerance (IGT) and diabetes mellitus (DM) comparing patients with and without CP (CP vs. NCP). METHODS: We administered an oral glucose tolerance test (OGTT) to all participants and, according to their glucose tolerance, classified them as NGT, IGT and DM. Insulin sensitivity and beta-cell functional parameters were derived from OGTT, hyperglycemic clamp and hyperinsulinemic euglycemic clamp. RESULTS: Studying 146 subjects, we found that beta-cell function and insulin secretion were significantly lower in CP compared to NCP patients. However, when we classified the subjects according to OGTT-derived glucose tolerance, we found no differences in beta-cell function or in insulin sensitivity between CP and NCP with the same glucose tolerance status. Of note, we found that arginine-stimulated insulin secretion is reduced only in subjects with CP and DM compared to NCP subjects with DM. CONCLUSIONS: Patients with CP had no specific alterations in insulin secretion and beta-cell function. However, in patients diagnosed with diabetes, we found a lower arginine-stimulated insulin secretion, a marker of reduced functional mass.

13.
Trends Endocrinol Metab ; 34(4): 216-230, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36858875

RESUMO

Our work is aimed at unraveling the role of the first-phase insulin secretion in the natural history of type 2 diabetes mellitus (T2DM) and its interrelationship with insulin resistance and with ß cell function and mass. Starting from pathophysiology, we investigate the impact of impaired secretion on glucose homeostasis and explore postmeal hyperglycemia as the main clinical feature, underlining its relevance in the management of the disease. We also review dietary and pharmacological approaches aimed at improving early secretory defects and restoring residual ß cell function. Furthermore, we discuss possible approaches to detect early secretory defects in clinical practice. By providing a journey through human and animal data, we attempt a unification of the recent evidence in an effort to offer a new outlook on ß cell secretion.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Células Secretoras de Insulina , Animais , Humanos , Secreção de Insulina , Diabetes Mellitus Tipo 2/tratamento farmacológico , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Resistência à Insulina/fisiologia , Glicemia
14.
Front Endocrinol (Lausanne) ; 14: 1124116, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324254

RESUMO

Background: Anti-PCSK9 monoclonal antibodies are effective in reducing LDL-C and cardiovascular events by neutralizing circulating PCSK9. PCSK9, however, is also expressed in tissues, including the pancreas, and studies on PCSK9 KO mice have shown impaired insulin secretion. Statin treatment is already known to affect insulin secretion. Our aim was to conduct a pilot study to evaluate the effect of anti-PCSK9 mAb on glucose metabolism and ß-cell function in humans. Methods: Fifteen non-diabetic subjects, candidates for anti-PCSK9 mAb therapy, were enrolled. All underwent OGTT at baseline and after 6 months of therapy. During OGTT, insulin secretion parameters were derived from C-peptide by deconvolution (ß cell glucose sensitivity). Surrogate insulin sensitivity indices were also obtained from OGTT (Matsuda). Results: Glucose levels during OGTT were unchanged after 6 months of anti-PCSK9 mAb treatment, as well as insulin and C-peptide levels. The Matsuda index remained unchanged, while ß-cell glucose sensitivity improved post-therapy (before: 85.3 ± 65.4; after: 118.6 ± 70.9 pmol min-1m-2mM-1; p<0.05). Using linear regression, we found a significant correlation between ßCGS changes and BMI (p=0.004). Thus, we compared subjects with values above and below the median (27.6 kg/m2) and found that those with higher BMI had a greater increase in ßCGS after therapy (before: 85.37 ± 24.73; after: 118.62 ± 26.83 pmol min-1m-2mM-1; p=0.007). There was also a significant correlation between ßCGS change and Matsuda index through linear regression (p=0.04), so we analyzed subjects who had values above and below the median (3.8). This subgroup analysis showed a slight though not significant improvement in ßCGS in more insulin resistant patients, (before: 131.4 ± 69.8; after: 170.8 ± 92.7 pmol min-1m-2mM-1; p=0.066). Conclusions: Our pilot study demonstrates that six-month treatment with anti-PCSK9 mAb improves ß-cell function, and does not alter glucose tolerance. This improvement is more evident in patients with greater insulin-resistance (low Matsuda) and higher BMI.


Assuntos
Glicemia , Insulina , Humanos , Animais , Camundongos , Projetos Piloto , Teste de Tolerância a Glucose , Glicemia/metabolismo , Peptídeo C , Insulina/metabolismo , Glucose
15.
Mol Metab ; 74: 101754, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37321370

RESUMO

BACKGROUND: Over the last decades, various approaches have been explored to restore sufficient ß-cell mass in diabetic patients. Stem cells are certainly an attractive source of new ß-cells, but an alternative option is to induce the endogenous regeneration of these cells. SCOPE OF REVIEW: Since the exocrine and endocrine pancreatic glands have a common origin and a continuous crosstalk unites the two, we believe that analyzing the mechanisms that induce pancreatic regeneration in different conditions could further advance our knowledge in the field. In this review, we summarize the latest evidence on physiological and pathological conditions associated with the regulation of pancreas regeneration and proliferation, as well as the complex and coordinated signaling cascade mediating cell growth. MAJOR CONCLUSIONS: Unraveling the mechanisms involved in intracellular signaling and regulation of pancreatic cell proliferation and regeneration may inspire future investigations to discover potential strategies to cure diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Ilhotas Pancreáticas , Humanos , Ilhotas Pancreáticas/fisiologia , Pâncreas/fisiologia , Células Secretoras de Insulina/fisiologia , Regeneração/fisiologia
16.
Nutrients ; 15(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37836486

RESUMO

Type 2 diabetes mellitus (T2DM) is one of the most widespread diseases worldwide. Lifestyle interventions, including diet and physical activity (PA), are fundamental non-pharmacological components of T2DM therapy. Exercise interventions are strongly recommended for people with or at risk of developing or already with overt diabetes, but adherence to PA guidelines in this population is still challenging. Furthermore, the heterogeneity of T2DM patients, driven by differing residual ß-cell functionality, as well as the possibility of practicing different types and intensities of PA, has led to the need to develop tailored exercise and training plans. Investigations on blood glucose variation in response to exercise could help to clarify why individuals do not respond in the same way to PA, and to guide the prescription of personalized treatments. The aim of this review is to offer an updated overview of the current evidence on the effects of different regimens and modalities of PA regarding glucose sensing and ß-cell secretory dynamics in individuals with prediabetes or T2DM, with a special focus on ß-cell function.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Humanos , Exercício Físico , Estado Pré-Diabético/terapia , Dieta , Glicemia
17.
Cells ; 11(13)2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35805193

RESUMO

In the last 30 years the adipose cell has been object of several studies, turning its reputation from an inert cell into the main character involved in the pathophysiology of multiple diseases, including the ongoing COVID-19 pandemic, which has changed the clinical scenario of the last two years. Composed by two types of tissue (white and brown), with opposite roles, the adipose organ is now classified as a real endocrine organ whose dysfunction is involved in different diseases, mainly obesity and type 2 diabetes. In this mini-review we aim to retrace the adipose organ history from physiology to physiopathology, to provide therapeutic perspectives for the prevention and treatment of its two main related diseases (obesity and type 2 diabetes) and to summarize the most recent discoveries linking adipose tissue to COVID-19.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Tecido Adiposo Marrom/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Obesidade/metabolismo , Pandemias
18.
Sci Data ; 9(1): 729, 2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36435908

RESUMO

Surface rupturing data from the historical earthquakes is used for obtaining empirical regression parameters for fault displacement hazard assessment. This paper represents an additional compilation and analysis effort, extending the first version of the SUrface Ruptures due to Earthquake (SURE) database. This new release contains slip measurements and mapped surface rupture traces of 50 surface rupturing earthquakes of reverse, normal, and strike-slip kinematics occurred all over the world between 1872 and 2019. As a novelty, a ranking scheme of the rupture features is applied to all the traces and slip measurements in the database. Fault ranking introduces geology as a primary analysis tool and allows the end user to obtain regression parameters suitable for the specific geological conditions at the site of interest. SURE 2.0 dataset consists of a table containing the background information about each earthquake, a table containing the slip measurement data of each event, and a joint shapefile containing all the surface rupture traces of the events in the database.

19.
Nutrients ; 15(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36615676

RESUMO

Alpha-lipoic acid (ALA) is a natural compound with antioxidant and pro-oxidant properties which has effects on the regulation of insulin sensitivity and insulin secretion. ALA is widely prescribed in patients with diabetic polyneuropathy due to its positive effects on nerve conduction and alleviation of symptoms. It is, moreover, also prescribed in other insulin resistance conditions such as metabolic syndrome (SM), polycystic ovary syndrome (PCOS) and obesity. However, several cases of Insulin Autoimmune Syndrome (IAS) have been reported in subjects taking ALA. The aim of the present review is to describe the main chemical and biological functions of ALA in glucose metabolism, focusing on its antioxidant activity, its role in modulating insulin sensitivity and secretion and in symptomatic peripheral diabetic polyneuropathy. We also provide a potential explanation for increased risk for the development of IAS.


Assuntos
Doenças Autoimunes , Neuropatias Diabéticas , Resistência à Insulina , Síndrome do Ovário Policístico , Ácido Tióctico , Feminino , Humanos , Ácido Tióctico/uso terapêutico , Neuropatias Diabéticas/tratamento farmacológico , Antioxidantes/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Doenças Autoimunes/tratamento farmacológico , Glucose/uso terapêutico
20.
J Biol Chem ; 285(52): 41044-50, 2010 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-20947509

RESUMO

Signaling by receptor tyrosine kinases regulates pancreatic ß cell function. Inactivation of insulin receptor (InsR), IGF1 receptor (Igf1r), or Irs1 in ß cells impairs insulin secretion. Conversely, Irs2 ablation impairs ß cell replication. In this study, we examined aspects of the Igf1r regulatory signaling cascade in ß cells. To examine genetically the involvement of Irs1 and Irs2 in Igf1r signaling, we generated double mutant mice lacking Igf1r specifically in pancreatic ß cells in an Irs1- or Irs2-null background. We show that Igf1r/Irs1 double mutants do not differ phenotypically from Irs1 single mutants and exhibit hyperinsulinemia, while maintaining normal ß cell mass and glucose tolerance. In contrast, lack of Igf1r function in ß cells aggravates the consequences of Irs2 ablation in double mutants and results in lethal diabetes by 6 weeks of age. This additivity of phenotypic manifestations indicates that Irs2 serves a pathway that is largely independent of Igf1r signaling. Consistent with the view that the latter is the InsR pathway, we show that combined ß cell-specific knock-out of both Insr and Igf1r results in a phenocopy of double mutants lacking Igf1r and Irs2. We conclude that Igf1r signals primarily through Irs1 and affects insulin secretion, whereas ß cell proliferation is mainly regulated by InsR using Irs2 as a downstream signaling effector. The insulin and IGF pathways appear to control ß cell functions independently and selectively.


Assuntos
Proteínas Substratos do Receptor de Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais/fisiologia , Animais , Proliferação de Células , Diabetes Mellitus/genética , Diabetes Mellitus/mortalidade , Glucose/genética , Glucose/metabolismo , Humanos , Hiperinsulinismo/genética , Hiperinsulinismo/metabolismo , Insulina/genética , Insulina/metabolismo , Proteínas Substratos do Receptor de Insulina/genética , Camundongos , Camundongos Knockout , Receptor IGF Tipo 1/genética , Receptor de Insulina/genética , Receptor de Insulina/metabolismo
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