A5074543896- Pancreatic function and diabetes
- Diabetes and associated disorders
- Metabolism, Diabetes, and Cancer
- Diabetes Management and Research
- Cellular transport and secretion
- Ion channel regulation and function
- Adipose Tissue and Metabolism
- Receptor Mechanisms and Signaling
- Calcium signaling and nucleotide metabolism
- Neuroscience and Neuropharmacology Research
- Diet, Metabolism, and Disease
- Cannabis and Cannabinoid Research
- Endoplasmic Reticulum Stress and Disease
- Diabetes Treatment and Management
- Adenosine and Purinergic Signaling
- Erythrocyte Function and Pathophysiology
- Neonatal Respiratory Health Research
- Pancreatitis Pathology and Treatment
- Ion Transport and Channel Regulation
- Cardiac Ischemia and Reperfusion
- Protein Kinase Regulation and GTPase Signaling
- Diet and metabolism studies
- Immune Cell Function and Interaction
- Respiratory Support and Mechanisms
- Neuropeptides and Animal Physiology
Karolinska Institutet
2016-2025
Sichuan University
2019-2025
West China Hospital of Sichuan University
2019-2025
Karolinska University Hospital
2015-2024
University of Miami
2015-2024
Tecnológico de Monterrey
2024
Nanyang Technological University
2014-2023
Pohang University of Science and Technology
2011-2022
Singapore Eye Research Institute
2017-2022
Singapore General Hospital
2017-2022
The cytoarchitecture of human islets has been examined, focusing on cellular associations that provide the anatomical framework for paracrine interactions. By using confocal microscopy and multiple immunofluorescence, we found that, contrary to descriptions prototypical in textbooks literature, did not show subdivisions. Insulin-immunoreactive β cells, glucagon-immunoreactive α somatostatin-containing δ cells were scattered throughout islet. Human clustered, most (71%) showed with other...
In the pancreatic islet, serotonin is an autocrine signal increasing beta cell mass during metabolic challenges such as those associated with pregnancy or high-fat diet. It still unclear whether relevant for regular islet physiology and hormone secretion. Here, we show that human cells produce secrete when stimulated increases in glucose concentration. Serotonin secretion from decreases cyclic AMP (cAMP) levels neighboring alpha via 5-HT1F receptors inhibits glucagon Without serotonergic...
High concentrations of glucose are considered to be toxic for the pancreatic β-cell. However, mechanisms underlying β-cell dysfunction and resulting cell death not fully characterized. In present study we have demonstrated that incubation islets β-cells from ob/ob mice Wistar rats with induced a process apoptotic death, as shown by DNA laddering, TdT-mediated dUTP-biotin nick end-labeling (TUNEL) technique, using DNA-staining dye HOECHST 33342. The obtained results show percentage cells was...
Hydrophobic low‐molecular‐mass proteins were isolated from minced pig lungs and separated into two fractions. Electrophoresis of protein fraction 1 showed major bands. Calculations molecular masses the electrophoretic mobilities are unreliable because extreme hydrophobicity peptides. However, bands at positions corresponding to apparent about 3 kDa 14 kDa, while sequence degradation disclosed only one structure. Electrophoretic separation 2 revealed band, an mass 6 kDa. Microheterogeneities...
Measurements of membrane capacitance were applied to dissect the cellular mechanisms underlying PKA-dependent and -independent stimulation insulin secretion by cyclic AMP. Whereas PKA-independent (Rp-cAMPS–insensitive) component correlated with a rapid increase in ∼80 fF that plateaued within ∼200 ms, became prominent during depolarizations >450 ms. The components cAMP-stimulated exocytosis differed regard cAMP concentration dependence; Kd values 6 29 μM for mechanisms, respectively....
The ATP-sensitive potassium channel is a key molecular complex for glucose-stimulated insulin secretion in pancreatic β cells. In humans, mutations either of the two subunits this channel, sulfonylurea type 1 receptor (Sur1) or Kir6.2, cause persistent hyperinsulinemic hypoglycemia infancy. We have generated and characterized <i>Sur1</i> null mice. Interestingly, these animals remain euglycemic large portion their life despite constant depolarization membrane, elevated cytoplasmic free...
Current methodologies to evaluate islet cell viability are largely based on tests that assess the exclusion of DNA-binding dyes. While these identify cells have lost selective membrane permeability, they do not allow us recognize apoptotic cells, which yet stain with Furthermore, current methods analysis discriminate between subsets in preparation and, particular, for selectively defining β-cell viability.For reasons we developed novel specific assessment content and human islets cellular...
Dopamine inhibits Na+,K+-ATPase activity in renal tubule cells. This inhibition is associated with phosphorylation and internalization of the alpha subunit, both events being protein kinase C-dependent. Studies purified preparations, fusion proteins site-directed mutagenesis, heterologous expression systems have identified two major C residues (Ser-11 Ser-18) rat alpha1 subunit isoform. To identify site(s) that mediates endocytosis response to dopamine, we performed mutagenesis these...
Several proteins that are of importance for membrane trafficking in the nerve terminal have recently been characterized. We used Western blot and immunohistochemistry to show synaptotagmin, synaptobrevin/VAMP (vesicle-associated protein), SNAP-25 (synaptosomal-associated protein 25 kDa), syntaxin present cells islets Langerhans endocrine pancreas. Synaptotagmin-like immunoreactivity (-LI) was localized granules within cytoplasm a few located periphery islets, identified as...
Hypoglycemic sulfonylureas represent a group of clinically useful antidiabetic compounds that stimulate insulin secretion from pancreatic β cells. The molecular mechanisms involved are not fully understood but believed to involve inhibition potassium channels sensitive adenosine triphosphate (K ATP channels) in the cell membrane, causing membrane depolarization, calcium influx, and activation secretory machinery. In addition these effects, also promoted exocytosis by direct interaction with...
Type I diabetes [insulin-dependent mellitus (IDDM)] is an autoimmune disease associated with the destruction of pancreatic β cells. Serum from patients IDDM increased L-type calcium channel activity insulin-producing cells and GH 3 derived a pituitary tumor. The subsequent increase in concentration free cytoplasmic Ca 2+ ([Ca ] i ) was DNA fragmentation typical programmed cell death or apoptosis. These effects serum were prevented by adding blocker voltage-activated channels. When depleted...