Pathophysiology of Diabetes Flashcards

What is the primary metabolic consequence of insulin deficiency in the liver?

Answer: Unchecked gluconeogenesis and glycogenolysis leading to fasting hyperglycemia

Insulin normally suppresses hepatic glucose production; without insulin, gluconeogenesis and glycogenolysis are unchecked, contributing to fasting hyperglycemia.

Which describes the mechanism by which SGLT2 inhibitors lower blood glucose?

Answer: They block SGLT2 transporters in the proximal tubule, preventing renal glucose reabsorption

SGLT2 inhibitors block sodium-glucose cotransporter 2 in the kidney's proximal tubule, causing glucosuria (urinary glucose excretion) and lowering blood glucose without insulin stimulation.

Maturity-onset diabetes of the young (MODY) is most commonly caused by which mechanism?

Answer: Single-gene mutations affecting beta-cell function or glucose sensing

MODY is a monogenic diabetes caused by single-gene mutations (most commonly in GCK, HNF1A, or HNF4A genes) that impair beta-cell function or glucose sensing.

What is the role of amylin in glucose regulation, and how does its deficiency affect diabetes management?

Answer: Amylin suppresses glucagon, slows gastric emptying, and promotes satiety; its deficiency contributes to postprandial hyperglycemia in type 1 diabetes

Amylin (co-secreted with insulin from beta cells) suppresses glucagon, slows gastric emptying, and promotes satiety; in T1D with beta-cell loss, amylin deficiency contributes to postprandial glucose excursions.

Which physiological mechanism explains why patients with longstanding type 1 diabetes may lose the early warning symptoms of hypoglycemia?

Answer: Repeated hypoglycemia episodes downregulate counter-regulatory hormone responses and shift the glycemic threshold for symptom generation

Hypoglycemia unawareness results from recurrent hypoglycemia that downregulates epinephrine and glucagon counter-regulatory responses and lowers the BG threshold at which symptoms appear.

Hepatic steatosis (fatty liver) is most commonly associated with which form of diabetes?

Answer: Type 2 diabetes and insulin resistance, especially with obesity

Non-alcoholic fatty liver disease (NAFLD) is strongly associated with type 2 diabetes and insulin resistance, particularly in the setting of visceral obesity.