Lipid Transport and Storage

Dr. Bibi KulsoomAssistant Professor

Department of Biochemistry

Countrywide Transport

Structure of Small Intestine

Structure of Small Intestine

Triglyceride Packing & Transport

Chylomicron

A-II

A-II

Lymphatic system

Blood Circulation

A II

Chylomicron

HDLApo C II, E

B 48

E

C II

Deloading of Chylomicrons

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Triacylgycerol Storage

Triacylgycerol Storage

http://www.trudicanavan.comhttp://www.vivo.colostate.edu

Brown Adipose Tissue

Chylomicron Transport to Liver

Countrywide Transport

Hepatic uptake of Chylomicron Remnants

Fate of Chylomicron Remnants

Chol

TGFFA

PhoL

Secretion of VLDL

Lipoproteins

Lipoprotein Structure

Composition of Lipoproteins

Lipoprotein Sources Main Lipid Apolipoproteins

Chylomicron Intestine Triacylgycerol A-I, A-II, A-IV, B-48,

C-I, C-II, C-III, E

Chylomicron

remnants

Chylomicron Triacylgycerol, Phospholipids, Cholesterol

B-48, E

VLDL Liver Triacylgycerol, Cholesterol

B-100, C-I, C-II, C-III

IDL VLDL Triacylgycerol B-100, E

LDL IDL Cholesterol B-100

HDL Liver, Intestine Phospholipids, Cholesterol

A-I, A-II, A-IV, C-I,C-II, C-III, D, E

Free fatty acids with Albumin

Adipose tissue

Free Fatty acid

Apolipoproteins

Apoprotein Function

ApoA-I Activates LCAT.

ApoA-II Enhanced hepatic lipase activity.

ApoA-IV Contributes to structure.

ApoB-48 Contributes to structure.

ApoB-100 Binds LDL receptor.

ApoC-I Probably activates LCAT.

ApoC-II Activates LPL.

ApoC-III Inhibits LPL.

ApoD Closely associated with LCAT.

ApoE Binds to LDL receptors.

Triacylglycerol Transport

Bood circulation

Harper’s Illustrated Biochemistry

Triacylglycerol & Cholesterol Transport

Harper’s Illustrated Biochemistry

Reverse Cholesterol Transport

Harper’s Illustrated Biochemistry

Dislioproteinemias

• Hypoliproteinemias– abetalipoproteinemia

• Hyperliproteinemias– Deficiency of

• LPL

• Hepatic lipase

• LCAT

• LDL receptor

• Apo E

etc

Suggested Reading:• Harper’s Illustrated Biochemistry, 28 Ed. McGraw-Hill.• Lehninger Principles of Biochemistry, 5 Ed. WHFreeman & Co.

Lipid Transport and Storage