Lipogenisis Flashcards
When does lipogenesis occur?
When someone consumes an excessive amount of CHO in their diet.
Where are excess CHO broken down & transported to for the process of lipogenesis?
Small Intestine > Blood Stream > Liver
Once excess CHO reach the liver, what is it then further converted into?
Glycogen (Branched Chain Polymer)
What anabolic hormone is responsible for the conversion of Glucose to Glycogen @ the Liver?
Insulin
For the process of Glycogenesis where is Insulin secreted from?
Pancreas (Beta Cells)
Once liver stores are full of glucose, excess glucose is then converted into what?
Acetyl CoA
What molecule is needed for Lipogenesis to begin the process of Fatty Acid Synthesis?
Acetyl CoA
What anabolic hormone is responsible for the conversion of “excess” Glucose at the Liver, into Acetyl CoA?
Insulin
After Fatty Acid Synthesis, Fatty Acids are then combined with ______ to form what?
Fatty Acids + Glycerol = TAG’s (Tri Acel Glycerol)
After TAG’s (Tri Acel Glycerol) are created where are they stored?
Small amount is stored in the liver & most is stored in adipose tissue
How are TAG’s (Tri Acel Glycerol) transported to adipose tissue?
VLDL (very low density lipoproteins)
- carrier proteins
What is Ectopic Fat?
A form of stored fat (similar to subcutaneous or visceral) specific to organs (like the liver) and the storage of TAG’s (Tri Acel Glycerol)
Adipose tissue primarily stores TAG’s, but can also manufacture TAG’s coming from where?
Circulating glucose in the blood stream
How big can adipocytes swell in the continuous storage of TAG’s (weight gain)?
Up to x3 their size.
As adipocytes reach full maturity (swelling from TAG storage) what then happens?
Differentiation. Stem Cells specific to adipocytes create more of them to create more storage space for TAG’s
With the “chronic” & excessive intake of CHO rich foods, what can happen to the liver & why?
Non-Alcoholic Fatty Liver Disease
> Too many TAG’s are created to fast and they begin to store themselves on/around organs b/c Adipocytes are already full & the body can’t transport them out of the liver fast enough.
Individuals with Fatty Liver Disease will commonly exhibit what with regard to transport lipoproteins?
Elevated Cholesterol
Why is cholesterol produced in excess with a disease like fatty liver disease?
It is synthesized with Acetyl CoA & Insulin, which are both more readily available @ the liver making it easy to synthesize under conditions of excess
What is the commitment or rate-limiting step of these metabolic pathways (lipogenesis, cholesterol synthesis, glycogenesis)?
Insulin secretion
For Lipogenesis, Insulin activates what rate-limiting enzyme?
Acetyl CoA Carboxylase
Acetyl CoA Carboxylase converts what into what?
Acetyl CoA > Fatty Acids
For Cholesterol Synthesis, Insulin activates what rate-limiting enzyme?
HMG Reductase
HMG Reductase converts what into what?
Acetyl CoA > Cholesterol