From Insulin Measurement to Partial Exocytosis Model: Advances in Single Pancreatic Beta Cell Amperometry over Four Decades DOI Creative Commons
Amir Hatamie, Xiulan He, Andrew G. Ewing

et al.

ACS Measurement Science Au, Journal Year: 2024, Volume and Issue: 4(6), P. 629 - 637

Published: Oct. 10, 2024

Single cell Amperometry (SCA) is a powerful, sensitive, high temporal resolution electrochemical technique used to quantify secreted molecular messengers from individual cells and vesicles. This has been extensively applied study the process of exocytosis, it also applied, albeit less frequently, investigate insulin exocytosis single pancreatic beta cells. Insufficient release can lead diabetes, chronic lifestyle disorder that affects millions people worldwide. review aims summarize highlight measurements via monitoring its secretion by SCA with micro- nanoelectrodes since 1990s explain how why serotonin as proxy for during Finally, we describe combination intracellular vesicle impact cytometry (IVIEC) led important findings regarding fractional types in These findings, reported recently, have opened new window pore formation, vesicles, mechanisms secretion. sensitive cellular electroanalysis approach should help development novel therapeutic strategies targeting diabetes future.

Language: Английский

Islet hormones at the intersection of glucose and amino acid metabolism DOI
Phillip J. White, Nicolai J. Wewer Albrechtsen, Jonathan E. Campbell

et al.

Nature Reviews Endocrinology, Journal Year: 2025, Volume and Issue: unknown

Published: March 7, 2025

Language: Английский

Citations

2
ER calcium stores contribute to glucose-induced Ca2+ waves and intercellular connectivity in mouse pancreatic islets DOI Creative Commons
Luis Fernando Delgadillo-Silva,

Karen Dakessian,

Guy A. Rutter

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: March 14, 2025

Abstract Defective insulin secretion is a hallmark of diabetes mellitus. Glucose-induced Ca 2+ oscillations are critical for the stimulation secretion, though mechanisms through which these propagate across islet poorly understood. Here, we use beta cell-targeted GCaMP6f to explore role endoplasmic reticulum (ER) mobilization in response submaximal (11mM) and hyperglycemic (25mM) glucose concentrations. Inhibition inositol 1,4,5 trisphosphate (IP 3 ) receptors, other ion channels, with 2-aminoethoxydiphenyl borate (2-APB) had minimal effects on initial peak or intercellular connectivity provoked by 11mM glucose. However, 2-APB lowered subsequent glucose-induced cytosolic increases at both 11 25mM Unexpectedly, activation IP receptors muscarinic acetylcholine receptor agonist carbachol impact elicited mM glucose, but waves 25 were more coordinated. To determine whether ER calcium was sufficient initiate next blocked sarco(endo)plasmic ATPase (SERCA) pumps thapsigargin, whilst preventing plasma membrane depolarization K ATP -channel opener, diazoxide. Under conditions, an increase followed secondary that slowly subsided. The application alongside diazoxide still enhanced dynamics, this activity uncoordinated cells connected. Our results show plays relatively minor initiation propagation On hand, stores required transition sustained waves. Highlights IP3R inhibition perturbs islets store insufficient generate cell GRAPHICAL ABSTRACT

Language: Английский

Citations

0
Measurement of Insulin Resistance in Cats With Chronic Kidney Disease DOI Creative Commons
İdil Baştan,

Cem Turker Cayiroglu,

Yeliz Kaya Kartal

et al.

Veterinary Medicine and Science, Journal Year: 2025, Volume and Issue: 11(3)

Published: April 26, 2025

ABSTRACT Background Chronic renal failure in cats is frequently associated with several well‐known consequences, including uremia, hypertension, anaemia and secondary hyperparathyroidism. In contrast to extensive studies on insulin resistance impaired glucose homeostasis humans chronic kidney disease (CKD), there a lack of research addressing these metabolic alterations CKD. Understanding the changes CKD essential for effective clinical management enhancing our knowledge disease's pathophysiology. Therefore, this study aimed evaluate secretion, concentrations homoeostasis model assessment (HOMA‐IR) non‐diabetic diagnosed stage 3–4 Methods Ten clinically healthy (healthy controls) fifteen CKD) were included study. Fasting blood glucose, insulin, urea, creatinine, phosphor, calcium, sodium, chlorine, potassium, albumin total protein levels analysed all patients. The HOMA‐IR index was calculated show existence resistance. Results Serum samples from 25 analysed, 15 10 controls. Cats exhibited significantly lower serum (6.05 ± 2.45pg/mL) compared (19.08 5.01pg/mL; p < 0.001). Glucose (149.89 61.49) notably higher than those controls (93.02 7.39; score (0.31 0.15) control group (0.62 0.16; Limitations limitations include small sample size, absence histopathological assessments fully characterise inflammatory status subjects. Conclusion Our findings indicate that, unlike humans, are CKD, suggesting potential mechanism β‐cell dysfunction reduced secretion contributing hyperglycaemia. Future focused oxidative stress conjunction pro‐inflammatory cytokines, mediators fPLI may be crucial understanding pathogenesis hypoinsulinaemia

Language: Английский

Citations

0
Pancreatic islets undergo functional and morphological adaptation during development of Barth Syndrome DOI
Christopher Carlein, Markus D. A. Hoffmann, Andressa G. Amaral

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: July 2, 2024

Abstract Barth syndrome is a multisystem genetic disorder caused by mutation in TAFAZZIN , gene that encodes phospholipid:lysophospholipid transacylase important for cardiolipin remodeling. Syndrome patients suffer from number of symptoms including early heart failure, fatigue, and systemic metabolic alterations, hypoglycemia. The endocrine pancreas central to glucose homeostasis, however, the impact defective remodeling on pancreatic islet function consequences metabolism unclear. Surprisingly, mouse model with global knockdown, we observed improved tolerance compared wildtype littermates. We show secretory are robustly maintained through various compensatory mechanisms increased uptake mitochondrial volume. Transcriptomics analyses revealed expression genes encoding proteins involved N-acetylglucosamine synthesis protein O -linked N-acetylglucosaminylation. These pathways might provide molecular mechanism coupling changes volume regulation.

Language: Английский

Citations

0
From Insulin Measurement to Partial Exocytosis Model: Advances in Single Pancreatic Beta Cell Amperometry over Four Decades DOI Creative Commons
Amir Hatamie, Xiulan He, Andrew G. Ewing

et al.

ACS Measurement Science Au, Journal Year: 2024, Volume and Issue: 4(6), P. 629 - 637

Published: Oct. 10, 2024

Single cell Amperometry (SCA) is a powerful, sensitive, high temporal resolution electrochemical technique used to quantify secreted molecular messengers from individual cells and vesicles. This has been extensively applied study the process of exocytosis, it also applied, albeit less frequently, investigate insulin exocytosis single pancreatic beta cells. Insufficient release can lead diabetes, chronic lifestyle disorder that affects millions people worldwide. review aims summarize highlight measurements via monitoring its secretion by SCA with micro- nanoelectrodes since 1990s explain how why serotonin as proxy for during Finally, we describe combination intracellular vesicle impact cytometry (IVIEC) led important findings regarding fractional types in These findings, reported recently, have opened new window pore formation, vesicles, mechanisms secretion. sensitive cellular electroanalysis approach should help development novel therapeutic strategies targeting diabetes future.

Language: Английский

Citations

0