Flashcards in B2.046 Prework 1 Overview of Hyperglycemia in Type 1 Diabetes Deck (23)
what is glucosuria?
sweet taste of urine
glucose being excreted in urine
what is SGLT2 and what is its function?
actively transports glucose from lumen into renal tubule cells by coupling with Na+ transport
what is the renal blood glucose threshold?
what are some examples of diabetic macro and microvascular complications?
distinguish between glycation and glycosylation
glycation- irreversible non enzymatic protein modifications
glycosylation- reversible, enzymatic protein modifications
what are 4 negative effects of chronic hyperglycemia
altered cellular redox potentials
oxidative stress and inflammation
what does Hb1Ac level exhibit?
the amount of Hb in the glycated state
more= more chronic hyperglycemia over last 6-8 weeks
how is glucose usually structured and what structure is susceptible to glycation?
usually in alpha and beta rings
fleetingly in a chain; in this form it can spontaneously glycate Hb
what is the primary hormonal basis for hyperglycemia in type 1 DM?
insulin is absent
glucagon, catechloamines, growth hormone, and glucocorticoids are present (counter regulatory hormones)
what is required for transport of glucose into skeletal muscle and adipose?
stimulated by insulin
what processes require insulin?
synthesis of glycogen by the liver and muscle
complete oxidation of glucose to CO2 by the heart, liver, and muscle
synthesis of fatty acids from glucose in the liver
what processes are negatively controlled by insulin?
glucose synthesis by the liver
lipolysis in the adipose
proteolysis in the muscle
opposition of counter regulatory hormones
stimulated by insulin in the liver
dephosphorylated/activated by insulin
phosphorylated/deactivated by glucagon
phosphorylated/activated by glucagon
dephosphorylated/inactivated by insulin
what is anaplerosis?
net synthesis of citric acid cycle intermediates
what enzyme catalyzes anaplerosis?
stimulated by high acetyl CoA levels and glucagon
what are important enzymes in gluconeogenesis?
fructose 1,6 bisphosphatase
what are the steps of complete oxidation of glucose that are not functional without insulin?
pyruvate dehydrogenase complex activation
citric acid cycle
what primary enzymes are required for synthesis of fatty acids by the liver?
pyruvate dehydrogenase complex
acetyl coA carboxylase
fatty acid synthase
how is acetyl coA carboxylase regulated?
down regulated and inhibited by phosphorylation when glucagon is released
what is lipolysis and what enzyme catalyzes it?
triacylglycerol hydrolysis: TAG + 3 H2O yields 3 FFAs + glycerol
catalyzed by hormone sensitive lipase (HSL)