glucosesensing

Glucose sensing refers to the detection and interpretation of glucose availability by cells, tissues, and engineered systems. It encompasses natural sensing mechanisms that regulate metabolism and behavior, as well as technological sensors used to monitor glucose levels in research and clinical care. Glucose sensing is central to energy homeostasis, feeding regulation, and glucose utilization.

In mammals, pancreatic beta cells sense extracellular glucose through the GLUT2 transporter and the enzyme glucokinase. The glucose-derived ATP rise closes ATP-sensitive potassium channels, leading to membrane depolarization, Ca2+ influx, and insulin secretion. Hypothalamic neurons also detect glucose; some cells are glucose-excited, increasing activity with higher glucose, while others are glucose-inhibited. Glucose sensing in the brain influences appetite, energy expenditure, and autonomic responses. Peripheral tissues adjust metabolism in response to glucose signals via insulin and other hormones, forming a systemic glucose-sensing network.

In microorganisms, glucose sensing commonly involves periplasmic binding proteins and two-component signaling systems that regulate chemotaxis and gene expression. In Saccharomyces cerevisiae, the plasma membrane sensors Snf3 and Rgt2 detect extracellular glucose and regulate expression of hexose transporters through the Rgt1-Mth1/Std1 pathway; Gpr1 acts as a G protein-coupled receptor linking glucose to cAMP signaling. Bacteria and yeast modulate metabolic pathways in response to glucose availability.

Glucose-sensing devices translate chemical or enzymatic reactions into measurable signals. Enzymatic electrochemical sensors use glucose oxidase or glucose dehydrogenase to generate current proportional to glucose concentration, enabling continuous glucose monitoring in diabetes care. Optical approaches, fluorescent or luminescent sensors, and emerging noninvasive methods are under development. Challenges include sensor accuracy, calibration, biofouling, and lag between blood and interstitial glucose.

Research on glucosesensing spans physiology, microbiology, biotechnology, and medical devices, with applications to metabolic research, disease management, and synthetic biology.