Beta-cell

BACKGROUND: In the development and progression of type 2 diabetes mellitus, β-cell dysfunction occurs after insulin resistance. Despite poor glycaemic control, there is a practice of increasing the dose of oral anti-diabetics or adding more drugs to the regimen due to the common perception that low endogenous insulin secretion is related to type 1 diabetes mellitus only and patient's poor compliance to injectables. Keeping this perspective in mind, this study was conducted to assess the prevalence of beta cell dysfunction by low serum C-peptide levels and its correlation with poor glycaemic control...

Chronically elevated levels of glucose are deleterious to pancreatic β cells and contribute to β cell dysfunction, which is characterized by decreased insulin production and a loss of β cell identity. The Krüppel-like transcription factor, Glis3 has previously been shown to positively regulate insulin transcription and mutations within the Glis3 locus have been associated with the development of several pathologies including type 2 diabetes mellitus. In this report, we show that Glis3 is significantly downregulated at the transcriptional level in INS1 832/13 cells within hours of being subjected to high glucose concentrations and that diminished expression of Glis3 is at least partly attributable to increased oxidative stress...

Human allogeneic pancreatic islet transplantation is a life-changing treatment for patients with severe Type 1 Diabetes (T1D) who suffer from hypoglycemia unawareness and high risk of severe hypoglycemia. However, intensive immunosuppression is required to prevent immune rejection of the graft, that may in turn lead to undesirable side effects such as toxicity to the islet cells, kidney toxicity, occurrence of opportunistic infections, and malignancies. The shortage of cadaveric human islet donors further limits islet transplantation as a treatment option for widespread adoption...

Mitochondria (mt) represent the vital hub of the molecular physiology of the cell, being decision-makers in cell life/death and information signaling, including major redox regulations and redox signaling. Now we review recent advances in understanding mitochondrial redox homeostasis, including superoxide sources and H2O2 consumers, i.e., antioxidant mechanisms, as well as exemplar situations of physiological redox signaling, including the intramitochondrial one and mt-to-cytosol redox signals, which may be classified as acute and long-term signals...

Redox status plays a multifaceted role in the intricate physiology and pathology of pancreatic beta-cells, the pivotal regulators of glucose homeostasis through insulin secretion. They are highly responsive to changes in metabolic cues where reactive oxygen species are part of it, all arising from nutritional intake. These molecules not only serve as crucial signaling intermediates for insulin secretion but also participate in the nuanced heterogeneity observed within the beta-cell population. A central aspect of beta-cell redox biology revolves around the localized production of hydrogen peroxide and the activity of NADPH oxidases which are tightly regulated and serve diverse physiological functions...

No abstract text is available yet for this article.

Despite advances in insulin delivery and glucose monitoring technology, prevention of the progression of secondary complications in patients with type 1 diabetes (T1DM) remains a challenge. Beta cell replacement therapy in the form of islet or pancreas transplantation can restore long-term normoglycaemia with sustained periods of insulin independence among T1DM patients. However, the same genetic, behavioural, or gut microbiota-related factors that promoted autoimmunity and primary islet destruction may also affect the function of transplanted islets and the ultimate results of transplant procedures...

The pandemic scale of diabetes mellitus is alarming, its complications remain devastating, and current treatments still pose a major burden on those affected and on the healthcare system as a whole. As the disease emanates from the destruction or dysfunction of insulin-producing pancreatic β-cells, a real cure requires their restoration and protection. An attractive strategy is to regenerate β-cells directly within the pancreas; however, while several approaches for β-cell regeneration have been proposed in the past, clinical translation has proven challenging...

The basal and glucose-induced insulin secretion from pancreatic beta cells is a tightly regulated process that is triggered in a Ca2+ -dependent fashion and further positively modulated by substances that raise intracellular levels of adenosine 3',5'-cyclic monophosphate (cAMP) or by certain antidiabetic drugs. In a previous study, we have temporally resolved the subplasmalemmal [Ca2+ ]i dynamics in beta cells that are characterized by trains of sharply delimited spikes, reaching peak values up to 5 µM...

Diabetes is a chronic metabolic disorder. Diabetes complications can affect many organs and systems in the body. Ganoderma lucidum (G. lucidum) contains various compounds that have been studied for their potential antidiabetic effects, including polysaccharides, triterpenoids (ganoderic acids, ganoderol B), proteoglycans, and G. lucidum extracts. G. lucidum polysaccharides (GLPs) and triterpenoids have been shown to act through distinct mechanisms, such as improving glucose metabolism, modulating the mitogen-activated protein kinase (MAPK) system, inhibiting the nuclear factor-kappa B (NF-κB) pathway, and protecting the pancreatic beta cells...

BACKGROUND: Pancreatogenic diabetes, a consequence of pancreatic tissue loss following pancreatectomy, poses a significant challenge for patients undergoing pancreatic surgery. Islet autotransplantation (IAT) offers a promising approach to prevent or alleviate pancreatogenic diabetes, but its application has been limited to individuals with painful chronic pancreatitis. METHODS: This study presents a 15-y clinical experience with the Milan Protocol, which expands IAT after pancreatectomy to a broader spectrum of patients with malignant and nonmalignant pancreatic diseases...

Pancreatic polypeptide (PP) is a postprandial hormone secreted from pancreatic islets that activates neuropeptide Y4 receptors (NPY4Rs). PP is known to induce satiety but effects at the level of the endocrine pancreas are less well characterized. In addition, rapid metabolism of PP by dipeptidyl peptidase-4 (DPP-4) limits the investigation of the effects of the native peptide. Therefore, in the present study, five novel amino acid substituted and/or fatty acid derivatized PP analogs were synthesized, namely [P3 ]PP, [K13 Pal]PP, [P3 ,K13 Pal]PP, [N-Pal]PP, and [N-Pal,P3 ]PP, and their impact on pancreatic beta-cell function, as well as appetite regulation and glucose homeostasis investigated...

Spinophilin is an F-actin binding and protein phosphatase 1 (PP1) targeting protein that acts as a scaffold of PP1 to its substrates. Spinophilin knockout (Spino-/- ) mice have decreased fat mass, increased lean mass, and improved glucose tolerance, with no difference in feeding behaviors. While spinophilin is enriched in neurons, its roles in non-neuronal tissues, such as beta cells of the pancreatic islets, are unclear. We have corroborated and expanded upon previous studies to determine that Spino-/- mice have decreased weight gain and improved glucose tolerance in two different models of obesity...

After birth, healthy neonates undergo a period of altered glucose metabolism, known as "transitional hypoglycemia". During the first 0-4 hours of life, the mean plasma glucose concentration decreases to 57 mg/dL, then by 72-96 hours of life increases to 82 mg/dL, well within the normal adult range. Recent data suggests that transitional hypoglycemia is due to persistence of the fetal beta cell's lower threshold for insulin release, resulting in a transient hyperinsulinemic state. While hypoglycemia is an expected part of the transition to postnatal life, it makes the identification of infants with persistent hypoglycemia disorders challenging...

Precision diagnosis is the keystone of clinical medicine. In East Asians, classical type 1 diabetes is uncommon in patients with youngonset diabetes diagnosed before age of 40, in whom a family history, obesity, and beta-cell and kidney dysfunction are key features. Young-onset diabetes affects one in five Asian adults with diabetes in clinic settings; however, it is often misclassified, resulting in delayed or non-targeted treatment. Complex aetiologies, long disease duration, aggressive clinical course, and a lack of evidence-based guidelines have contributed to variable care standards and premature death in these young patients...

Autoimmune liver diseases are associated with an increased risk of diabetes, yet the underlying mechanisms remain unknown. In this cross-sectional study, we investigated the glucose-regulatory disturbances in patients with autoimmune hepatitis (AIH, n=19), primary biliary cholangitis (PBC, n=15), and primary sclerosing cholangitis (PSC, n=6). Healthy individuals (n=24) and patients with metabolic dysfunction-associated steatotic liver disease (MASLD, n=18) were included as controls. Blood samples were collected during a 120 min oral glucose tolerance test...

No abstract text is available yet for this article.

G-protein coupled receptor-120 (GPR120; FFAR4) is a free fatty acid receptor, widely researched for its glucoregulatory and insulin release activities. This study aimed to investigate the metabolic advantage of FFAR4/GPR120activation using combination therapy. C57BL/6 mice, fed a High Fat Diet (HFD) for 120 days to induce obesity-diabetes, were subsequently treated with a single daily oral dose of FFAR4/GPR120 agonist Compound A (CpdA) (0.1μmol/kg) alone or in combination with sitagliptin (50mg/kg) for 21 days...

Type 1 diabetes mellitus (T1DM) is a chronic disease affecting millions worldwide. Insulin therapy is currently the golden standard for treating T1DM; however, it does not restore the normal glycaemic balance entirely, which increases the risk of secondary complications. Beta-cell therapy may be a possible way of curing T1DM and has already shown promising results in the clinic. However, low retention rates, poor cell survival, and limited therapeutic potential are ongoing challenges, thus increasing the need for better cell encapsulation devices...

The increasing global prevalence and associated comorbidities need innovative approaches for type 2 diabetes mellitus (T2DM) prevention and treatment. Genetics contributes significantly to T2DM susceptibility, and genetic counseling is significant in detecting and informing people about the diabetic risk. T2DM is also intricately linked to overnutrition and obesity, and nutritional advising is beneficial to mitigate diabetic evolution. However, manipulating pancreatic cell plasticity and transdifferentiation could help beta cell regeneration and glucose homeostasis, effectively contributing to the antidiabetic fight...