Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Eur J Clin Invest ; 54(3): e14121, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37929812

RESUMO

AIMS: Improving the composition of circulating fatty acids (FA) leads to a reduction in cardiovascular diseases (CVD) in high-risk individuals. The membrane fluidity of red blood cells (RBC), which reflects circulating FA status, may be a valid biomarker of cardiovascular (CV) risk in type 2 diabetes (T2D). METHODS: Red blood cell membrane fluidity, quantified as general polarization (GP), was assessed in 234 subjects with T2D, 86 with prior major CVD. Based on GP distribution, a cut-off of .445 was used to divide the study cohort into two groups: the first with higher GP, called GEL, and the second, defined as lower GP (LGP). Lipidomic analysis was performed to evaluate FA composition of RBC membranes. RESULTS: Although with comparable CV risk factors, the LGP group had a greater percentage of patients with major CVD than the GEL group (40% vs 24%, respectively, p < .05). Moreover, in a logistic regression analysis, a lower GP value was independently associated with the presence of macrovascular complications. Lipidomic analysis showed a clear shift of LGP membranes towards a pro-inflammatory condition due to higher content of arachidonic acid and increased omega 6/omega 3 index. CONCLUSIONS: Increased membrane fluidity is associated with a higher CV risk in subjects with T2D. If confirmed in prospective studies, membrane fluidity could be a new biomarker for residual CV risk assessment in T2D.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Humanos , Membrana Eritrocítica/metabolismo , Fluidez de Membrana , Estudos Prospectivos , Fatores de Risco , Eritrócitos/metabolismo , Ácidos Graxos/metabolismo , Fatores de Risco de Doenças Cardíacas , Biomarcadores/metabolismo
2.
Langenbecks Arch Surg ; 409(1): 184, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38862717

RESUMO

PURPOSE: Post-operative pancreatic fistula (POPF) remains the main complication after distal pancreatectomy (DP). The aim of this study is to evaluate the potential benefit of different durations of progressive stapler closure on POPF rate and severity after DP. METHODS: Patients who underwent DP between 2016 and 2023 were retrospectively enrolled and divided into two groups according to the duration of the stapler closure: those who underwent a progressive compression for < 10 min and those for ≥ 10 min. RESULTS: Among 155 DPs, 83 (53.5%) patients underwent pre-firing compression for < 10 min and 72 (46.5%) for ≥ 10 min. As a whole, 101 (65.1%) developed POPF. A lower incidence rate was found in case of ≥ 10 min compression (34-47.2%) compared to < 10 min compression (67- 80.7%) (p = 0.001). When only clinically relevant (CR) POPFs were considered, a prolonged pre-firing compression led to a lower rate (15-20.8%) than the < 10 min cohort (32-38.6%; p = 0.02). At the multivariate analysis, a compression time of at least 10 min was confirmed as a protective factor for both POPF (OR: 5.47, 95% CI: 2.16-13.87; p = 0.04) and CR-POPF (OR: 2.5, 95% CI: 1.19-5.45; p = 0.04) development. In case of a thick pancreatic gland, a prolonged pancreatic compression for at least 10 min was significantly associated to a lower rate of CR-POPF compared to < 10 min (p = 0.04). CONCLUSION: A prolonged pre-firing pancreatic compression for at least 10 min seems to significantly reduce the risk of CR-POPF development. Moreover, significant advantages are documented in case of a thick pancreatic gland.


Assuntos
Pancreatectomia , Fístula Pancreática , Complicações Pós-Operatórias , Grampeamento Cirúrgico , Humanos , Fístula Pancreática/prevenção & controle , Fístula Pancreática/etiologia , Pancreatectomia/efeitos adversos , Pancreatectomia/métodos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Grampeamento Cirúrgico/métodos , Grampeadores Cirúrgicos , Adulto , Fatores de Tempo , Neoplasias Pancreáticas/cirurgia
3.
Int J Mol Sci ; 25(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38892122

RESUMO

Pancreatic islet isolation is critical for type 2 diabetes research. Although -omics approaches have shed light on islet molecular profiles, inconsistencies persist; on the other hand, functional studies are essential, but they require reliable and standardized isolation methods. Here, we propose a simplified protocol applied to very small-sized samples collected from partially pancreatectomized living donors. Islet isolation was performed by digesting tissue specimens collected during surgery within a collagenase P solution, followed by a Lympholyte density gradient separation; finally, functional assays and staining with dithizone were carried out. Isolated pancreatic islets exhibited functional responses to glucose and arginine stimulation mirroring donors' metabolic profiles, with insulin secretion significantly decreasing in diabetic islets compared to non-diabetic islets; conversely, proinsulin secretion showed an increasing trend from non-diabetic to diabetic islets. This novel islet isolation method from living patients undergoing partial pancreatectomy offers a valuable opportunity for targeted study of islet physiology, with the primary advantage of being time-effective and successfully preserving islet viability and functionality. It enables the generation of islet preparations that closely reflect donors' clinical profiles, simplifying the isolation process and eliminating the need for a Ricordi chamber. Thus, this method holds promises for advancing our understanding of diabetes and for new personalized pharmacological approaches.


Assuntos
Separação Celular , Ilhotas Pancreáticas , Humanos , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/citologia , Separação Celular/métodos , Doadores Vivos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Insulina/metabolismo , Glucose/metabolismo , Secreção de Insulina
4.
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
5.
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
6.
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
7.
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
8.
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
9.
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
10.
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
11.
J Biol Chem ; 291(41): 21485-21495, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27535223

RESUMO

The insulin/insulin-like growth factor (IGF) signaling pathway plays a critical role in the regulation of islet cell biology. However, the signaling pathway(s) utilized by insulin to directly modulate ß-cells is unclear. To interrogate whether insulin exerts endocrine effects in regulating proteins in the insulin/IGF-1 signaling cascade in vivo in physiological states via the insulin receptor, we designed two experimental approaches: 1) glucose gavage and 2) hyperinsulinemic intravenous infusion, for studies in either ß-cell specific insulin receptor knock-out (ßIRKO) or control mice. Immunostaining of sections of pancreas (collected immediately after glucose gavage or insulin infusion) from controls showed significant increases in pAKT+, p-p70S6K+, and pERK+ ß-cells and a significant decrease in % nuclear FoxO1+ ß-cells compared with corresponding vehicle-treated groups. In contrast, in ßIRKOs, we observed no significant changes in pAKT+ or p-p70S6K+ ß-cells in either experiment; however, pERK+ ß-cells were significantly increased, and an attenuated decrease in % nuclear FoxO1+ ß cells was evident in response to glucose gavage or insulin infusion. Treatment of control and ßIRKO ß-cell lines with glucose or insulin showed significantly decreased % nuclear FoxO1+ ß-cells suggesting direct effects. Furthermore, blocking MAPK signaling had virtually no effect on FoxO1 nuclear export in controls, in contrast to attenuated export in ßIRKO ß-cells. These data suggest insulin acts on ß-cells in an endocrine manner in the normal situation; and that in ß-cells lacking insulin receptors, insulin and glucose minimally activate the Akt pathway, while ERK phosphorylation and FoxO1 nuclear export occur independently of insulin signaling.


Assuntos
Proteína Forkhead Box O1/metabolismo , Células Secretoras de Insulina/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor de Insulina/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Animais , Proteína Forkhead Box O1/genética , Glucose/genética , Glucose/metabolismo , Camundongos , Camundongos Knockout , Fosforilação/fisiologia , Proteínas Proto-Oncogênicas c-akt/genética , Receptor de Insulina/genética
12.
Diabetologia ; 57(7): 1291-303, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24824733

RESUMO

Regeneration of mature cells that produce functional insulin represents a major focus and a challenge of current diabetes research aimed at restoring beta cell mass in patients with most forms of diabetes, as well as in ageing. The capacity to adapt to diverse physiological states during life and the consequent ability to cope with increased metabolic demands in the normal regulation of glucose homeostasis is a distinctive feature of the endocrine pancreas in mammals. Both beta and alpha cells, and presumably other islet cells, are dynamically regulated via nutrient, neural and/or hormonal activation of growth factor signalling and the post-transcriptional modification of a variety of genes or via the microbiome to continually maintain a balance between regeneration (e.g. proliferation, neogenesis) and apoptosis. Here we review key regulators that determine islet cell mass at different ages in mammals. Understanding the chronobiology and the dynamics and age-dependent processes that regulate the relationship between the different cell types in the overall maintenance of an optimally functional islet cell mass could provide important insights into planning therapeutic approaches to counter and/or prevent the development of diabetes.


Assuntos
Células Secretoras de Insulina/citologia , Ilhotas Pancreáticas/citologia , Animais , Humanos , Insulina/metabolismo , Ilhotas Pancreáticas/crescimento & desenvolvimento , Transdução de Sinais/fisiologia
13.
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.

14.
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.

15.
Nat Commun ; 15(1): 4527, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811550

RESUMO

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.


Assuntos
Glucose , Homeostase , Células Secretoras de Insulina , Insulina , Camundongos Knockout , Receptores de Interleucina , Animais , Células Secretoras de Insulina/metabolismo , Receptores de Interleucina/metabolismo , Receptores de Interleucina/genética , Feminino , Humanos , Masculino , Insulina/metabolismo , Camundongos , Glucose/metabolismo , Secreção de Insulina , Camundongos Endogâmicos C57BL , Interleucina 22 , Intolerância à Glucose/metabolismo , Interleucinas/metabolismo , Interleucinas/genética , Envelhecimento/metabolismo
16.
Cancers (Basel) ; 16(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39001409

RESUMO

The influencing role of resection margin (R) status on long-term outcomes, namely overall (OS) and disease-free survival (DFS), after pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC) is not still clear. The aim of this study is to evaluate the prognostic impact of R status after PD and to define tumor characteristics associated with a positive resection margin (R1). All PDs for PDAC performed between 2012 and 2023 were retrospectively enrolled. The effect of R status, patient clinico-demographic features, and tumor features on OS and DFS were assessed. One-hundred and sixty-seven patients who underwent PD for PDAC were included in the study. R0 was achieved in 105 cases (62.8%), while R1 was evidenced in 62 patients (37.1%). R1 was associated with a decreased OS (23 (13-38) months) as compared to R0 (36 (21-53) months) (p = 0.003). Similarly, DFS was shorter in R1 patients (10 (6-25) months) as compared to the R0 cohort (18 (9-70) months) (p = 0.004), with a consequent higher recurrence rate in cases of R1 (74.2% vs. 64.8% in the R0 group; p = 0.04). In the multivariate analysis, R1 and positive lymph nodes (N+) were the only independent influencing factors for OS (OR: 1.6; 95% CI: 1-2.5; p = 0.03 and OR: 1.7; 95% CI: 1-2.8; p = 0.04) and DFS (OR: 1.5; 95% CI: 1-2.1; p = 0.04 and OR: 1.8; 95% CI: 1.1-2.7; p = 0.009). Among 111 patients with N+ disease, R1 was associated with a significantly decreased DFS (10 (8-11) months) as compared to R0N+ patients (16 (11-21) months) (p = 0.05). In conclusion, the achievement of a negative resection margin is associated with survival benefits, particularly in cases of N1 disease. In addition, R0 was recognized as an independent prognostic feature for both OS and DFS. This further outlines the relevant role of radical surgery on long-term outcomes.

17.
Acta Diabetol ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831203

RESUMO

Type 2 diabetes represents a growing challenge for global public health. Its prevalence is increasing worldwide, and, like obesity, it affects progressively younger populations compared to the past, with potentially greater impact on chronic complications. Dual glucagon like peptide 1 (GLP1) and glucose-dependent insulinotropic peptide (GIP) receptor agonists are among the new pharmacological strategies recently developed to address this challenge. Tirzepatide, characterized by its ability to selectively bind and activate receptors for the intestinal hormones GIP and GLP-1, has been tested in numerous clinical studies and is already currently authorized in several countries for the treatment of type 2 diabetes and obesity. In this context, the aim of the present document is to summarize, in the form of a narrative literature review, the currently available data on the main mechanisms of action of GIP/GLP-1 co-agonists and the clinical effects of tirzepatide evaluated in various clinical trials.

18.
Diabetes ; 73(1): 93-107, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862465

RESUMO

In this study, we identified new lipid species associated with the loss of pancreatic ß-cells triggering diabetes. We performed lipidomics measurements on serum from prediabetic mice lacking ß-cell prohibitin-2 (a model of monogenic diabetes) patients without previous history of diabetes but scheduled for pancreaticoduodenectomy resulting in the acute reduction of their ß-cell mass (∼50%), and patients with type 2 diabetes (T2D). We found lysophosphatidylinositols (lysoPIs) were the main circulating lipid species altered in prediabetic mice. The changes were confirmed in the patients with acute reduction of their ß-cell mass and in those with T2D. Increased lysoPIs significantly correlated with HbA1c (reflecting glycemic control), fasting glycemia, and disposition index, and did not correlate with insulin resistance or obesity in human patients with T2D. INS-1E ß-cells as well as pancreatic islets isolated from nondiabetic mice and human donors exposed to exogenous lysoPIs showed potentiated glucose-stimulated and basal insulin secretion. Finally, addition of exogenous lysoPIs partially rescued impaired glucose-stimulated insulin secretion in islets from mice and humans in the diabetic state. Overall, lysoPIs appear to be lipid species upregulated in the prediabetic stage associated with the loss of ß-cells and that support the secretory function of the remaining ß-cells. ARTICLE HIGHLIGHTS: Circulating lysophosphatidylinositols (lysoPIs) are increased in situations associated with ß-cell loss in mice and humans such as (pre-)diabetes, and hemipancreatectomy. Pancreatic islets isolated from nondiabetic mice and human donors, as well as INS-1E ß-cells, exposed to exogenous lysoPIs exhibited potentiated glucose-stimulated and basal insulin secretion. Addition of exogenous lysoPIs partially rescued impaired glucose-stimulated insulin secretion in islets from mice and humans in the diabetic state. LysoPIs appear as lipid species being upregulated already in the prediabetic stage associated with the loss of ß-cells and supporting the function of the remaining ß-cells.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Ilhotas Pancreáticas , Estado Pré-Diabético , Humanos , Camundongos , Animais , Insulina , Lisofosfolipídeos , Glucose/farmacologia , Insulina Regular Humana
19.
Antibiotics (Basel) ; 12(7)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37508216

RESUMO

Acute pancreatitis is a complex inflammatory disease with significant morbidity and mortality. Despite advances in its management, the role of antibiotics in the prophylaxis and treatment of acute pancreatitis remains controversial. The aim of this comprehensive review is to analyze current evidence on the use of antibiotics in acute pancreatitis, focusing on prophylactic and therapeutic strategies. Prophylactic use aims to prevent local and systemic infections. However, recent studies have questioned the routine use of antibiotics for prophylaxis and highlighted the potential risks of antibiotic resistance and adverse effects. In selected high-risk cases, such as infected necrotizing pancreatitis, prophylactic antibiotic therapy may still be beneficial. As for therapeutic use, antibiotics are usually used to treat infected pancreatic necrosis and extrapancreatic infections. When selecting an antibiotic, the microbiologic profile and local resistance patterns should be considered. Combination therapy with broad-spectrum antibiotics is often recommended to cover both Gram-positive and Gram-negative pathogens. Recent research has highlighted the importance of individualized approaches to antibiotic use in acute pancreatitis and underscored the need for a tailored approach based on patient-specific factors. This review also highlights the potential role of new antimicrobial agents and alternative strategies, such as probiotics, in the management of acute pancreatitis.

20.
Biomedicines ; 11(1)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36672664

RESUMO

Pancreatic cancer (PC) is an aggressive malignancy and the fourth leading cause of cancer death in the United States and Europe. It is estimated that PC will be the second leading cause of cancer death by 2030. In addition to late diagnosis, treatment resistance is a major cause of shortened survival in pancreatic cancer. In this context, there is growing evidence that microbes play a regulatory role, particularly in therapy resistance and in creating a microenvironment in the tumor, that favors cancer progression. The presence of certain bacteria belonging to the gamma-proteobacteria or mycoplasmas appears to be associated with both pharmacokinetic and pharmacodynamic changes. Recent evidence suggests that the microbiota may also play a role in resistance mechanisms to immunotherapy and radiotherapy. However, the interactions between microbiota and therapy are bilateral and modulate therapy tolerance. Future perspectives are increasingly focused on elucidating the role of the microbiota in tumorigenesis and processes of therapy resistance, and a better understanding of these mechanisms may provide important opportunities to improve survival in these patients.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa