Aims: We aimed to assess physical activity (PA) levels, adherence to PA guidelines, and fitness capacity in individuals with type 1 diabetes (T1D) and control population.
Methods: This cross-sectional study included 232 T1D and 248 controls. PA levels (IPAQ-SF questionnaire), adherence to guidelines (>150 min/week of moderate-to-vigorous PA), fitness capacity (VOmax, maximal incremental test on a cycle ergometer and 1RM test) were assessed, along with other clinical variables.
Direct lineage reprogramming of one somatic cell into another without transitioning through a progenitor stage has emerged as a strategy to generate clinically relevant cell types. One cell type of interest is the pancreatic insulin-producing β cell whose loss and/or dysfunction leads to diabetes. To date it has been possible to create β-like cells from related endodermal cell types by forcing the expression of developmental transcription factors, but not from more distant cell lineages like fibroblasts.
View Article and Find Full Text PDFAims: to investigate if a High Intensity Interval Training (HIIT) protocol improves glycemic control and fitness capacity, compared to traditional moderate Intensity Continuous Training (MICT) exercise.
Methods: 30 sedentary individuals with type 1 diabetes (T1D) and 26 healthy controls were assigned to a 3-week HIIT or MICT protocol. Blood glucose levels by continuous glucose monitoring system and fitness status were compared before and after the study period.
Liver fibrosis staging is a key element driving the prognosis of patients with chronic liver disease. Currently, biopsy is the only technique capable of diagnosing liver fibrosis in patients with alcohol-related liver disease (ArLD) and nonalcoholic fatty liver disease (NAFLD) unequivocally. Noninvasive (e.
View Article and Find Full Text PDFAmyloid deposits in pancreatic islets, mainly formed by human islet amyloid polypeptide (hIAPP) aggregation, have been associated with loss of β-cell mass and function, and are a pathological hallmark of type 2 diabetes (T2D). Treatment with chaperones has been associated with a decrease in endoplasmic reticulum stress leading to improved glucose metabolism. The aim of this work was to investigate whether the chemical chaperone 4-phenylbutyrate (PBA) prevents glucose metabolism abnormalities and amyloid deposition in obese agouti viable yellow (A) mice that overexpress hIAPP in β cells (A hIAPP mice), which exhibit overt diabetes.
View Article and Find Full Text PDFObjective: Pancreatic β-cell dysfunction is a central feature in the pathogenesis of type 2 diabetes (T2D). Accumulating evidence indicates that β-site APP-cleaving enzyme 2 (BACE2) inhibition exerts a beneficial effect on β-cells in different models of T2D. Thus, targeting BACE2 may represent a potential therapeutic strategy for the treatment of this disease.
View Article and Find Full Text PDFObjective: Pancreatic β-cell failure is central to the development and progression of type 2 diabetes (T2D). The aggregation of human islet amyloid polypeptide (hIAPP) has been associated with pancreatic islet inflammation and dysfunction in T2D. Alpha1-antitrypsin (AAT) is a circulating protease inhibitor with anti-inflammatory properties.
View Article and Find Full Text PDFHMG20A (also known as iBRAF) is a chromatin factor involved in neuronal differentiation and maturation. Recently small nucleotide polymorphisms (SNPs) in the HMG20A gene have been linked to type 2 diabetes mellitus (T2DM) yet neither expression nor function of this T2DM candidate gene in islets is known. Herein we demonstrate that HMG20A is expressed in both human and mouse islets and that levels are decreased in islets of T2DM donors as compared to islets from non-diabetic donors.
View Article and Find Full Text PDFThe pancreatic β-cell transcriptome is highly sensitive to external signals such as glucose oscillations and stress cues. MicroRNAs (miRNAs) have emerged as key factors in gene expression regulation. Here, we aimed to identify miRNAs that are modulated by glucose in mouse pancreatic islets.
View Article and Find Full Text PDFJarid2 is a component of the Polycomb Repressor complex 2 (PRC2), which is responsible for genome-wide H3K27me3 deposition, in embryonic stem cells. However, Jarid2 has also been shown to exert pleiotropic PRC2-independent actions during embryogenesis. Here, we have investigated the role of Jarid2 during pancreas development.
View Article and Find Full Text PDFHuman islet amyloid polypeptide (hIAPP) aggregation is associated with β-cell dysfunction and death in type 2 diabetes (T2D). we aimed to determine whether treatment with chemical chaperone 4-phenylbutyrate (PBA) ameliorates hIAPP-induced β-cell dysfunction and islet amyloid formation. Oral administration of PBA in hIAPP transgenic (hIAPP Tg) mice expressing hIAPP in pancreatic β cells counteracted impaired glucose homeostasis and restored glucose-stimulated insulin secretion.
View Article and Find Full Text PDFProopiomelanocortin (POMC) neurons are critical sensors of nutrient availability implicated in energy balance and glucose metabolism control. However, the precise mechanisms underlying nutrient sensing in POMC neurons remain incompletely understood. We show that mitochondrial dynamics mediated by Mitofusin 1 (MFN1) in POMC neurons couple nutrient sensing with systemic glucose metabolism.
View Article and Find Full Text PDFBACE2 (β-site APP-cleaving enzyme 2) is a protease expressed in the brain, but also in the pancreas, where it seems to play a physiological role. Amyloidogenic diseases, including Alzheimer's disease and type 2 diabetes (T2D), share the accumulation of abnormally folded and insoluble proteins that interfere with cell function. In T2D, islet amyloid polypeptide (IAPP) deposits have been shown to be a pathogenic key feature of the disease.
View Article and Find Full Text PDFAlterations during development of metabolic key organs such as the endocrine pancreas affect the phenotype later in life. There is evidence that in utero or perinatal exposure to bisphenol-A (BPA) leads to impaired glucose metabolism during adulthood. However, how BPA exposure during pregnancy affects pancreatic β-cell growth and function in offspring during early life has not been explored.
View Article and Find Full Text PDFHuman islet amyloid polypeptide (hIAPP) is the major component of amyloid deposits in islets of type 2 diabetic patients. hIAPP misfolding and aggregation is one of the factors that may lead to β-cell dysfunction and death. Endogenous chaperones are described to be important for the folding and functioning of proteins.
View Article and Find Full Text PDFThe toxic effects of human islet amyloid polypeptide (IAPP) on pancreatic islets have been widely studied. However, much less attention has been paid to the physiologic actions of IAPP on pancreatic β cells, which secrete this peptide together with insulin upon glucose stimulation. Here, we aimed to explore the signaling pathways and mitogenic actions of IAPP on β cells.
View Article and Find Full Text PDFContext: Diabetes is frequently diagnosed late, when the development of complications is almost inevitable, decreasing the quality of life of patients. However, early detection of affected individuals would allow the implementation of timely and effective therapies.
Objective: Here we set to describe the profile of circulating microRNAs (miRNAs) in prediabetic patients with the intention of identifying novel diagnostic and therapeutic tools.
BACE2 (β-site APP-cleaving enzyme 2) is a protease localized in the brain, where it appears to play a role in the development of Alzheimer disease (AD). It is also found in the pancreas, although its biologic function is not fully known. Amyloidogenic diseases, including AD and type 2 diabetes mellitus (T2D), share the accumulation of abnormally folded and insoluble proteins that interfere with cell function.
View Article and Find Full Text PDFIn type 2 diabetes, beta-cell dysfunction is thought to be due to several causes, one being the formation of toxic protein aggregates called islet amyloid, formed by accumulations of misfolded human islet amyloid polypeptide (hIAPP). The process of hIAPP misfolding and aggregation is one of the factors that may activate the unfolded protein response (UPR), perturbing endoplasmic reticulum (ER) homeostasis. Molecular chaperones have been described to be important in regulating ER response to ER stress.
View Article and Find Full Text PDFDiabetes is caused by loss or dysfunction of pancreatic beta cells. Generation of beta cells in vitro is a promising strategy to develop a full-scale cell therapy against diabetes, and the development of methods without gene transfer may provide safer protocols for human therapy. Here we show that thyroid hormone receptors are expressed in embryonic murine pancreas.
View Article and Find Full Text PDFNMDA receptor (NMDAR) stimulation promotes neuronal survival during brain development. Cerebellar granule cells (CGCs) need NMDAR stimulation to survive and develop. These neurons differentiate and mature during its migration from the external granular layer to the internal granular layer, and lack of excitatory inputs triggers their apoptotic death.
View Article and Find Full Text PDFType 2 diabetes mellitus (T2DM) is a major disease affecting nearly 280 million people worldwide. Whilst the pathophysiological mechanisms leading to disease are poorly understood, dysfunction of the insulin-producing pancreatic beta-cells is key event for disease development. Monitoring the gene expression profiles of pancreatic beta-cells under several genetic or chemical perturbations has shed light on genes and pathways involved in T2DM.
View Article and Find Full Text PDFHeterozygous HNF1A mutations cause pancreatic-islet beta-cell dysfunction and monogenic diabetes (MODY3). Hnf1alpha is known to regulate numerous hepatic genes, yet knowledge of its function in pancreatic islets is more limited. We now show that Hnf1a deficiency in mice leads to highly tissue-specific changes in the expression of genes involved in key functions of both islets and liver.
View Article and Find Full Text PDFObjective: The evolutionary conservation of transcriptional mechanisms has been widely exploited to understand human biology and disease. Recent findings, however, unexpectedly showed that the transcriptional regulators hepatocyte nuclear factor (HNF)-1alpha and -4alpha rarely bind to the same genes in mice and humans, leading to the proposal that tissue-specific transcriptional regulation has undergone extensive divergence in the two species. Such observations have major implications for the use of mouse models to understand HNF-1alpha- and HNF-4alpha-deficient diabetes.
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