L20: Diabetes & Hypoglycaemia Flashcards
During fasting how does the liver make glucose?
→Glycogenolysis: - breakdown of glycogen store to glucose
→ Gluconeogenesis:- making glucose from non-glucose sources, e.g. lactate, alanine, fatty acids
Which cells in the pancreas release glucagon?
→ alpha cells
What are the roles of insulin on adipose tissue?
→ glucose uptake
→ lipogenesis
→ reduced lipolysis
What is the effect of insulin on muscle?
→ increased glucose uptake
→ increased glycogen synthesis
→ increased protein synthesis
What is the role of insulin in the liver?
→ reduced gluconeogenesis
→ increased glycogen synthesis
→ increased liponeogenesis
What are the functions of adrenaline in metabolism?
→ Mobilises fuels in acute stress
→ stimulates glycogenolysis;
→ stimulates fatty acid release
What are the functions of cortisol on metabolism?
→ Changing long term
→ amino acid mobilization
→ gluconeogenesis
What are the functions of GH in metabolism?
→ Inhibits insulin action
→ stimulates lipolysis
Define diabetes
→ a metabolic disorder characterised by chronic hyperglycaemia, glycosuria and associated abnormalities of lipid and protein metabolism
What are the 4 classifications of diabetes?
→ Type 1
→ Type 2: Insulin secretion is retained but there is target organ resistance to its actions
→ Secondary: chronic pancreatitis, pancreatic surgery, secretion of antagonists
→ Gestational
What is the most common cause of Type1 DM?
→ autoimmune destruction of B-cells
→ strong link with HLA genes within the MHC region on chromosome 6
Which demographic is Type 1DM predominant in?
→ children and young adults
Describe the pathogenesis of Type 1 DM?
→ Destruction of B-cells starts with autoantigen formation
→ Autoantigens are presented to T-lymphocytes to initiate autoimmune response
What is the most commonly detected antibody associated with Type 1 DM?
→ the islet cell antibody
What are the three antigens that antibodies work against in Type 1 diabetes
→ glutamic acid decarboxylase (GAD);
→ insulin;
→ a tyrosine-phosphatase-like molecule
What is amylin?
→ a glucoregulatory peptide hormone co-secreted with insulin
→ lowers blood glucose by slowing gastric emptying,
→ suppressing glucagon output from pancreatic cells
What does amylin suppress?
→ glucagon output
What leads to ketoacidosis in Type 1 DM?
→ increased lipolysis → Increased free fatty acids (FFA → Increased FFA oxidation (liver