storage of energy in body

excess glucose

uploaded to liver to synthesize fatty acids

lipogenesis steps

acetyl CoA → citrate → leave mitochondria → convert back into acetyl CoA → acetyl CoA units bound together to form fatty acids → become triglycerides → stored in adipocytes

excess AA

liver & kidneys use glucogenic AA to make glucose

ketogenic AA converted to acetyl CoA → ketone bodies when carbs limited 

overnight fast 

blood glucose falls → pancreas secretes hormone glucagon → liver increase glycogenolysis → blood glucose maintained 

glycogenolysis

breakdown of glycogen into glucose

when glycogen stores are depleted…

glucagon stimulates gluconeogenesis in liver 

fasting beyond glycogen depletion

body break down lean body tissue → convert glucogenic AA to glucose

once enough lean tissue → nervous tissue use ketones as fuel

how does obesity lead to insulin resistance

excess adipose tissue → proteins in adipocytes signal inflammation → cells become unresponsive to insulin

type 2 diabetes

nonalcoholic fatty liver 

insulin-resistant cells don’t take up glucose & fatty acids → excess lipolysis release excess fatty acids → stimulate triglyceride synthesis in liver

metabolic syndrome

liver becomes insulin resistant so ability to regulate glycogen synthesis & gluconeogenesis affected

metabolic syndrome mechanism

glucose produced in liver → bloodstream → blood glucose rises → pancreas secretes more insulin