LIPIDSDaniel Bučánek

Jan Gembík

Lipids

• Fatty acids

• Glycerides

• Nonglycerol lipids

• Complex lipids

Types of lipids

Fatty acids

Saturated

Unsaturated

Glycerides

Neutra

Phospoglycerides

Nonglycerides

Sphingolipids

Steroid

Waxes

Complex lipids

Lipoproteins

Glykolipids

Lipid functions

• Creates a barrier for the cell• Controls flow of materials

Cell membrane structure

Energy storage• Fats stored in adipose tissue

Hormones and vitamins

• Hormones – communication between cells• Vitamins – assist in the regulation of biological

processes

Fatty acids structureLong chain monocarboxylic acids

CH3(CH2)nCOOH• Size range: C12 – C14

• Always an even number of carbon

• Saturated – no double bonds

• Unsaturated – one or more double bonds

Fatty acids structure

CH3

CH2CH2

CH2CH2

CH2CH2

CH2CH2

CH2CH2

CH2CH2

CH2CH2

COH

O

CH3

CH2CH2

CH2CH2

CHCH

CH2CH2

CH2CH2

CHCH

CH2CH2

COH

O

Saturated

Unsaturated

CH3

CH2 CH2

CH2 CH2

CH CH

CH2 CH2

CH2 CH2

CH CH

CH2 CH2

C OH

Ocis

trans

Some common fatty acids

Common name

IUPAC name MP °C Formula

Presence of double bonds reduced melting point. In nature, all double bonds are ´cis´.

Steric acid

Oleic acid

Reactions of fatty acidsReact like any other carboxylic acid.

Unsaturated fatty acids eicosanoids

• All are unsaturated.• All have twenty carbons.• Some are essential fatty acids

Can´t be produced by the body.

examples: linoleic and linoleic acids

Eicosanoids

Three groups: prostaglandins, leukotrienes, thromboxanes

ProstaglandinsOriginaly isolated from seminal fluid.

All are derived from arachidonic acid.

Prostaglandins

Prostaglandins

• Stimulation of smooth muscles• Regulation of steroid production• Inhibition of gastric secretion• Inhibition of hormone-sensitive lipases• Inhibition / stimulation of plate aggregation• Regulation of nerve transmission• Sensitization of pain• Mediation of inflamantory response

Biological effect

Blood clotting

Produced by platelets in blood.Stimulates constrictions of blood vessel.Aggregation of platelets.

Thromboxane A2

Prostacyclin

Produced by cells that line blood vessels.Reverses effects of throbmoxane A2

Aspirin therapy

Acts as anticoagulent – antiplatelet aggregation.

Inflammantory response

Protective mechanism when tissue is damaged.

Ressults in swelling, redness, fever and pain.

Prostaglandins promote this response.

Drug like aspirin and ibuprofen

• Anti - inflammatories

• Block prostaglandins synthesis

• Cause reduction in this response

Neutral glyceridesEster of glycerol and fatty acid.

Principal function is energy storage – fat or oil.

CH2

CH

CH2

OH

OH

OH

CCH2

CH2

CH2CH2

CH2CH2

CH2CH2

CH2CH2

CH3

OH

O

CH2

CH

CH2

O

OH

OH

CCH2

CH2

CH2CH2

CH2CH2

CH2CH2

CH2CH2

CH3O

+

Fats and oils

• Both are triglycerides• Fats

• typically obtained from animals• solids at room temperature• made from saturated fatty acids

• Oils• typically obtained from plants• liquids at room temperature• made from unsaturated fatty acids

Waxes

• Water insoluble and hard to hydrolyze• Often used to provide a protective coating

(leaves, skin, fur, hair….)• Bees wax and Sebum are examples• Ester of a fatty acid and a long chain alcohol

Phospoglycerides

Lipids that contain a phosphate group.

Modified fat where a phospate replaces one of the fatty acid chain.

Uses

• production of cell membrenes

• emulsifying agents

Lecithin-phosphatidylcholin

Polar head

Nonpolar tail

Nonglycerol lipidsSphingolipids• A type of phospolipid not derived from fat.• Used primarily in nerve tissue – myelin sheath.• In people, 25% of all lipids are sphingolipids.

Steroids

Broad class of compounds that all have the same base structure.

Cholesterol

Principal membrane lipid for fluidity.

Complex lipids

• Lipids bound to other molecules• Combination results in the structure

Complex lipids

Four major classes of plasma lipoproteins

• Chilomikrons• Very low-density lipoproteins (VLDL)• Low-density lipoproteins (LDL)• High-density lipoproteins (HDL)

Each is composed of several types of lipids

Composition of complex lipoproteins

Composition of complex lipoproteins

Function of lipoproteins

• Chilomikrons

Transport triglicerides from intestines to other tissue – except kdneys

• VLDL

Bind triglycerides in liver and carry them to fat tissue• LDL

Carry choresterol to peripheral tissue• HLD

Bound to plasma choresterol

Transport cholesterol to liver

Transport of lipoproteins

Source

• Some information from internet.

• Some information from lecture of Biochemistry.

• And some information from 12.Lesson with name Biochemistry.