Nicholas Whitticar

Journal article Journal of the Endocrine Society · October 5, 2024 AbstractDisclosure: N.B. Whitticar: None. B.P. List: None. N. Bruce: None. R. Bertram: None. C.S. Nunemaker: None.Long before type 2 diabetes ensues, pancreatic islets underg ... Full text Cite

A Trypan Blue-Based ELISA Practice Test to Evaluate Trainee Performance.

Journal article Journal of chemical education · June 2023 Enzyme-Linked Immunosorbent Assay (ELISA) is a valuable tool in various chemical and biological fields for investigating the presence and quantity of proteins of interest in given samples. The high importance of the assay makes it widely used in biological ... Full text Cite

Similarities in Calcium Oscillations Between Neonatal Mouse Islets and Mature Islets Exposed to Chronic Hyperglycemia.

Journal article Endocrinology · July 2022 Pulsatility is important to islet function. As islets mature into fully developed insulin-secreting micro-organs, their ability to produce oscillatory intracellular calcium ([Ca2+]i) patterns in response to glucose also matures. In this study, we measured ... Full text Cite

Developing an In Vitro Platform to Mimic the Pancreas‐Liver Endocrine Axis

Journal article The FASEB Journal · May 2022 Insulin is secreted from pancreatic islets in a pulsatile manner due to alternating periods of cellular activity and rest. The resulting pulses of insulin are critical for proper hormonal signaling and blood glucose regulation ... Full text Cite

Loss of growth hormone signaling in the mouse germline or in adulthood reduces islet mass and alters islet function with notable sex differences.

Journal article American journal of physiology. Endocrinology and metabolism · June 2021 In the endocrine pancreas, growth hormone (GH) is known to promote pancreatic islet growth and insulin secretion. In this study, we show that GH receptor (GHR) loss in the germline and in adulthood impacts islet mass in general but more profoundly in male ... Full text Cite

The Capacity to Secrete Insulin Is Dose-Dependent to Extremely High Glucose Concentrations: A Key Role for Adenylyl Cyclase.

Journal article Metabolites · June 2021 Insulin secretion is widely thought to be maximally stimulated in glucose concentrations of 16.7-to-30 mM (300-to-540 mg/dL). However, insulin secretion is seldom tested in hyperglycemia exceeding these levels despite the Guinness World Record being 147.6 ... Full text Cite

A Practical Guide to Rodent Islet Isolation and Assessment Revisited.

Journal article Biological procedures online · March 2021 Insufficient insulin secretion is a key component of both type 1 and type 2 diabetes. Since insulin is released by the islets of Langerhans, obtaining viable and functional islets is critical for research and transplantation. The effective and efficient is ... Full text Cite

Natural Compound α-PGG and Its Synthetic Derivative 6Cl-TGQ Alter Insulin Secretion: Evidence for Diminishing Glucose Uptake as a Mechanism.

Journal article Diabetes, metabolic syndrome and obesity : targets and therapy · January 2021 PurposePreviously we showed that natural compound α-penta-galloyl-glucose (α-PGG) and its synthetic derivative 6-chloro-6-deoxy-1,2,3,4-tetra-O-galloyl-α-D-glucopyranose (6Cl-TGQ) act to improve insulin signaling in adipocytes by increasing glucos ... Full text Cite

Reflections on undergraduate research mentoring.

Journal article Biophysicist (Rockville, Md.) · August 2020 Recruiting talented high school and college students to consider a career in the biomedical or biophysical sciences is important, yet often difficult. Encouraging students in regions like Appalachia adds additional challenges due to socioeconomic hurdles a ... Full text Cite

Reducing Glucokinase Activity to Enhance Insulin Secretion: A Counterintuitive Theory to Preserve Cellular Function and Glucose Homeostasis.

Journal article Frontiers in endocrinology · January 2020 Pancreatic beta-cells are the only cells in the body that can synthesize and secrete insulin. Through the process of glucose-stimulated insulin secretion, beta-cells release insulin into circulation, stimulating GLUT4-dependent glucose uptake into peripher ... Full text Cite

Reducing Glucokinase Activity Restores Endogenous Pulsatility and Enhances Insulin Secretion in Islets From db/db Mice.

Journal article Endocrinology · November 2018 An early sign of islet failure in type 2 diabetes (T2D) is the loss of normal patterns of pulsatile insulin release. Disruptions in pulsatility are associated with a left shift in glucose sensing that can cause excessive insulin release in low glucose (rel ... Full text Cite

An Automated Perifusion System for Modifying Cell Culture Conditions over Time.

Journal article Biological procedures online · January 2016 BackgroundCells are continuously exposed to changes in their environment. Endocrine systems, in particular, communicate by rhythms and feedback loops. In this study, we developed an automated system to produce such conditions for cultured cells in ... Full text Cite