29 Triacyglycerol (TAG) Metabolism

Site TAG

Liver and adipose tissue

Pathway TAG

1. TAG kena sisntesis dari glycerol 3 phosphate and fatty acyl coA

2. ini glycerol 3 phosphate kena ambil dari 2 pathway iaitu dari DHAP yang kena ambil dari glucose dan dari glycerol by glycorol kinase enzyme

3. adipose tissue tiada ni enzyme glycerol kinase

4. jadi, adipose tissue cuma produce glycerol 3 phosphate dari glucose saja.

5. jadi, bila glycolysis kena activated iaitu masa fed condition saja baru TAG kena synthesis di adipose tissue

Lipolysis (breakdown of TG into free fatty acids and glycerol)

guna enzyme lypase

since glycerol tidak boleh kena utilize di fat adipocyte, dia kena diffuse di into plasma (darah) terus kena bawa pg liver dan kidney yang ada glycerol kinase. campin kan.

ini free fatty acid yang kena formed by lipolysis pula can be reconverted in the tissue to acyl CoA by acyl CoA synthetase dan re-esterification with glycerol 3-p to form triacylglycerol

Fate of triacylglycerol synthesized in adipose tissues and liver

di adipose tissue, TAG kena store as “depot fat”. ini fat ready kena guna bila2 masa saja. dia boleh bergerak

di liver pula, TAG yang baru kena guna kena export dari liver as VLDL. sikit saja TAG kena store di liver

Lipid storage disease

kena panggil lipidoses. kena inherit ni disease. lipid accumulate di cell dan tissues

sbb tu orang x produce enough enzyme utk metabolise lipid atau badan dia produce juga enzyme tapi x work properly

over time, terlalu byk fat ini akan cause permanent cellular and tissue damage terutamanya di brain, peripheral nervous system, liver, spleen dan bone marrow

Tay sachs disease

accumulation of gangliosides, rapid neurodegeneration, blinedess, muscular weakness, seizures

gaucher disease

accumulation of glucocerebrosides, most common lysosomal storage disease, hepatosplenomegaly, osteoporosis of long bones, CNS involvement in rare infantile and juvenile forms

metachromatic leukodystrophy

accumulation of sulfatides, cognitive deterioration, demyelination, progressive paralysis, dementia in adult form, nerve stain yellowish brown

Krabbe disease

accumulation of galactocerebrosides, mental and motor deterioration, blindness and deafness, near total loss of myelin, globoid bodies in white matter of brain

Gm1 gangliosidosis

accumulation of gangliosides and keratan sulfate, neurologic deterioration, hepatosplenomegaly, skeletal deformities, cherry red macula

Sandhoff’s disease

accumulation of GM2 and globosides, same neurologic with tay sachs but with visceral involvement as well

Fabry disease

accumulation of globosidases, reddish purple skin rash, kidney and heart failure, burning pain in lower extremities

Nieman- pick disease

accumulation of sphingomyelin, hepatosplenomegaly, neurodegenerative course (Type A)

Faber disease

Accumulation of ceramide, painful and progressive join deformity, subcutaneous nodules of lipid- laden cells, hoarse cry, tissues show granulomas