Obesity Therapies Flashcards
How does insulin affect weight lose
Decreased insulin = increased weight loss
Disadvantages of liposuction
Fluid accumulation
Nerve damage
Risk of infection
Expensive
May not be covered by insurance
Not permanent
describe gastric bypass surgery
small pouch is created at the top of the stomach so you feel full with less food
Decrease ghrelin which reduces hunger
Which steps of the TG biosynthetic pathway make good drug targets for obesity therapy
GPATs- maybe
AGPATs- maybe, but not AGPAT2
Lipins- probably not
DGATs- DGAT1, not DGAT2
DGAT1 ko mouse vs DGAT2 ko mouse
DGAT1 ko: viable and healthy, reduced TG and adipose tissue, obesity resistance, no fatty liver
DGAT2 ko: Lethal, no energy store, skin defect/dehydration
Which tissues does DGAT1 affect
Liver and small intestines
Where does dietary fat absorption occur
Small intestine
What are enterocytes
absorptive cells in intestines
T/F Dietary TG cannot be absorbed by enterocytes intact
True
Dietary cannot be absorbed by enterocytes intact, how does the body get around this? (how does dietary TG get to CM in circulation)
TG are disassembled by pancreatic lipase to fatty acids and 2-monoacylglycerol
Transporters move fatty acids and 2-MG into enterocytes from the intestinal lumen
TG are packaged into CM with phospholipids and specific proteins
CM is then secreted into the lymph then circulation
What is the role of DGAT1 in the small intestine
Catalyzes the resynthesis of dietary TG
What is the pathway responsible for the resynthesis of dietary TG
Monoacylglycerol acyltransferase (MGAT) pathway
What is monoacylglycerol acyltransferase-2 for? (what is the substrate)
It is produced in the small intestine by pancreatic lipase and transported into intestinal cells (enterocytes)
2-monoacylglycerol is the substrate by MGAT to synthesize 1,2-DG
Role of 1,2-DG
DGAT1 uses 1,2-DG to synthesize TG that are packaged into chylomicrons and released into the circulation
What is the postprandial triglyceridemic response when subjects are given a drink high in fat and blood is taken every hour? Why is this the response?
Blood TG levels increase after 1 hour then decrease after 2 hours
This represents TG secretion from the small intestines and TG clearance by other tissues (CM clearance)