Assignment 1Assignment 1

THEME: LIPIDS IT’S TYPES THEME: LIPIDS IT’S TYPES & FUNCTION& FUNCTION

DVM, 2DVM, 2NDND SEMESTER SEMESTERPresented by. Dr Waleed Qadar,Presented by. Dr Waleed Qadar,

Asif Ghafoor,Asif Ghafoor,Yasir Ali &Yasir Ali &Maria ImtiazMaria Imtiaz

LIPIDSLIPIDS

. Biomolecules that have the . Biomolecules that have the common property of being soluble in common property of being soluble in organic (nonpolar) solvents, but not organic (nonpolar) solvents, but not in water.in water.

Lipids are mainly composed of C, H Lipids are mainly composed of C, H and O.Also Contain Nitrogen and and O.Also Contain Nitrogen and phosphorusphosphorus

They may be small or very complex.They may be small or very complex.

LipidsLipids

Form of Store Energy. Stored in a Form of Store Energy. Stored in a Fat Cell (Adipose cell).Fat Cell (Adipose cell).

Part of membranes (lipoprotein)Part of membranes (lipoprotein) Serve as chemical messengers Serve as chemical messengers

(hormones)(hormones)

BIOLOGICAL ROESBIOLOGICAL ROES

EXPLAIN IN THE NEXT SLIDESEXPLAIN IN THE NEXT SLIDES

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Energy StorageEnergy Storage

Humans store Energy in the form of Humans store Energy in the form of fatsfats

Some Energy storage is in the form of Some Energy storage is in the form of the carbohydrate glycogen – fast the carbohydrate glycogen – fast energyenergy

Fats produce 50% more energy per Fats produce 50% more energy per gram than carbohydratesgram than carbohydrates

9 kcal/gram compared to 4 kcal/gram9 kcal/gram compared to 4 kcal/gram

Membrane ComponentsMembrane Components

Because lipids are insoluble in Because lipids are insoluble in water, they work well as membranes water, they work well as membranes to separate compartments in the to separate compartments in the bodybody

The structure of lipids makes them The structure of lipids makes them water repellent or hydrophobicwater repellent or hydrophobic

MessengersMessengers

Primary messengers like steroidsPrimary messengers like steroids Secondary messengers like Secondary messengers like

prostaglandins or thromboxanesprostaglandins or thromboxanes

Classification of Classification of LipidsLipids

Classified into;Classified into;

1)1) Fats and waxesFats and waxes

2)2) Complex LipidsComplex Lipids1)1) GlycerophospholipidsGlycerophospholipids

2)2) GlycolipidsGlycolipids

3)3) LipoproteinLipoprotein

4)4) waxeswaxes

2)2) ProstaglandinsProstaglandins

FatsFats

Fats are Fats are estersesters Alcohol part is always Alcohol part is always

glycerolglycerol Acid part varies but Acid part varies but

is a “Fatty Acid”is a “Fatty Acid”

glycerolH2C

HC

H2C

OH

OH

OH

palmitic acid

CCH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH3 OH

O

a typical “fatty acid”

Structure of FatsStructure of Fats Fatty Acids Fatty Acids (FA)(FA)

1)1) Practically all straight chain with no Practically all straight chain with no branchesbranches

2)2) 10 to 20 C in length10 to 20 C in length3)3) Contain an even number of CContain an even number of C

The body builds FA from The body builds FA from two carbon unitstwo carbon units

of acetic acid (acetate ion)of acetic acid (acetate ion)4)4) Those with double bonds are usually Those with double bonds are usually

in the cis isomer formationin the cis isomer formation

palmitic acid

CCH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH3 OH

O

Structure of FatsStructure of Fats

Fatty Acids + Glycerol = FAT Fatty Acids + Glycerol = FAT (an (an ester)ester)

C (CH2)16 CH3

O

HC

H2C

H2C C (CH2)12 CH3O

O

O

O C (CH2)16 CH3

O

C (CH2)16 CH3

O

HC

H2C

H2C C (CH2)12 CH3O

O

O

O C (CH2)16 CH3

O

glycerol

first FA

second FA

third FA

Structure of FatsStructure of Fats FATSFATS

Also called TriacylglycerideAlso called Triacylglyceride Fats are insoluble in waterFats are insoluble in water Exist as both saturated and Exist as both saturated and

unsaturated FAunsaturated FA

Structure of FatsStructure of Fats FATSFATS

Saturated Fatty AcidsSaturated Fatty Acids Fit together well - close, parallel Fit together well - close, parallel

alignmentalignment Regular patternRegular pattern

Unsaturated Fatty AcidsUnsaturated Fatty Acids cis/trans double bonds do not allow cis/trans double bonds do not allow

regular packingregular packing LOWER mp and bp lower than the Sat’d. LOWER mp and bp lower than the Sat’d.

FAFA

Common Fatty Acids To Common Fatty Acids To KnowKnow

Properties of FatsProperties of Fats

Physical State - FATSPhysical State - FATS Animal fatsAnimal fats

generally solids at RTgenerally solids at RT contain mostly saturated FAcontain mostly saturated FA

Plant and Fish oilsPlant and Fish oils generally liquids at RTgenerally liquids at RT contain more unsaturated FAcontain more unsaturated FA

Properties of FatsProperties of Fats

PURE Fats PURE Fats Colorless, odorless, and tastelessColorless, odorless, and tasteless Tastes, odors, colors are caused Tastes, odors, colors are caused

by substances dissolved in the fatsby substances dissolved in the fats

From Yahoo Images

Classification of Classification of LipidsLipids

Gly

cero

l

FA

FA

FA

Simple and complex lipids

Simple Complex

Classification of Classification of LipidsLipids

GlycolipidsGlycerophospholipids

Gly

cero

l

FA

FA

FA

Simple and complex lipids

Simple Complex

Classification of Classification of LipidsLipids

GlycolipidsGlycerophospholipids

Gly

cero

l

FA

FA

FA FASphi

ngos

ine

GLUCOSEGALACTOSE

Simple and complex lipids

Simple Complex

Phosphoglycerides Sphingolipids

Classification of Classification of LipidsLipids

GlycolipidsGlycerophospholipids

Gly

cero

l

FA

FA

FA FASphi

ngos

ine

GLUCOSEGALACTOSE

Simple and complex lipids

Simple Complex

Phosphoglycerides Sphingolipids

Classification of Classification of LipidsLipids

GlycolipidsGlycerophospholipids

Gly

cero

l

FA

FA

FA

Gly

cero

l

FA

FA

PO43- ALCOHOL FASp

hing

osin

e

GLUCOSEGALACTOSE

Simple and complex lipids

Simple Complex

Phosphoglycerides Sphingolipids

Classification of Classification of LipidsLipids

GlycolipidsGlycerophospholipids

Gly

cero

l

FA

FA

FA

Gly

cero

l

FA

FA

PO43- ALCOHOL

Sphi

ngos

ine FA

PO43- CHOLINE FASp

hing

osin

e

GLUCOSEGALACTOSE

Sphi

ngos

ine

Simple and complex lipids

Simple Complex

GlycerophospholipidsGlycerophospholipids

Glycerol is the alcoholGlycerol is the alcohol Two acids are Fatty AcidsTwo acids are Fatty Acids Third is esterified to POThird is esterified to PO44

3-3- and and cholinecholine

The Fatty Acid on carbon 2 is The Fatty Acid on carbon 2 is unsaturatedunsaturated

choline

CH2 CH2OHNH3C

CH3

CH3

+

glycerolH2C

HC

H2C

OH

OH

OH

Coating of nerve axons (myelin)Coating of nerve axons (myelin) Alcohol portion is sphingosine Alcohol portion is sphingosine (not (not

glycerol)glycerol) A long chain fatty acid is connected to A long chain fatty acid is connected to

the NHthe NH22

The End OH group is esterified by The End OH group is esterified by phosphorylcholinephosphorylcholine

SphingolipidsSphingolipids

CH(CH2)12CH3 CH CH CH CH2

OH NH2 OH

sphingosine

Glycolipids contain carbohydratesGlycolipids contain carbohydrates They also use sphingosineThey also use sphingosine One type is the cerebrosidesOne type is the cerebrosides

occur in the brain occur in the brain (7% of dry weight!)(7% of dry weight!)

present at nerve synapsespresent at nerve synapses

GlycolipidsGlycolipids

O

OH

OH

HO

CH2OHO

HNO

OH

a glucocerebroside

SphingolipidsSphingolipids

Can you find the sphingosine????

SteroidsSteroids

A third major class of lipids:A third major class of lipids: They are all based on this They are all based on this

structurestructure

H3C CH3

CH3

HO

CH3

CH3

cholesterol

CholesterolCholesterol most abundant steroid in the bodymost abundant steroid in the body cell membrane componentcell membrane component raw material for other raw material for other

steroids synthesissteroids synthesis Exists in both free and esterified formsExists in both free and esterified forms

Esterifies with FAEsterifies with FA Gallstones are almost pure cholesterol (physio)Gallstones are almost pure cholesterol (physio) Necessary for human lifeNecessary for human life Manufactured in the liver – body keeps a set Manufactured in the liver – body keeps a set

amountamount

H3C CH3

CH3

HO

CH3

CH3

cholesterol

LipoproteinsLipoproteins

Transport cholesterol, and fatsTransport cholesterol, and fats Types of LipoproteinsTypes of Lipoproteins

HDL = hi density lipoprotein HDL = hi density lipoprotein (the (the good Kind)good Kind)

33% protein and 30% cholesterol33% protein and 30% cholesterol LDL = lo density lipoprotein LDL = lo density lipoprotein (the not (the not

good kind)good kind) 25% protein and 50 % cholesterol25% protein and 50 % cholesterol

Steroid HormonesSteroid HormonesCholesterol is starting material for Cholesterol is starting material for

synthesis of Progesterone:synthesis of Progesterone: Precursor of sex hormones Precursor of sex hormones

and adrenocorticoid hormonesand adrenocorticoid hormones

C

CH3

O

O

CH3

CH3

progesterone

H3C CH3

CH3

HO

CH3

CH3

cholesterol

Hormones from Hormones from ProgesteroneProgesterone

testosteroneO

CH3

CH3OH

Steroid HormonesSteroid Hormones

Sex Hormones - TestosteroneSex Hormones - Testosterone Promotes normal growth of male sex Promotes normal growth of male sex

organsorgans Synthesized in testesSynthesized in testes

from cholesterolfrom cholesterol Secretion results inSecretion results in

22ndnd sex characteristics sex characteristics

Steroid HormonesSteroid Hormones

Sex Hormones - EstradiolSex Hormones - Estradiol Regulates cyclic changes in the uterusRegulates cyclic changes in the uterus Synthesized from Synthesized from

testosteronetestosterone Menstrual CycleMenstrual Cycle

Increased at beginningIncreased at beginning

of cycleof cycle Help in thickness of uterusHelp in thickness of uterus Also give direction LH to ovulate.Also give direction LH to ovulate.

estradiol

HO

CH3OH

Prostaglandins (SH)Prostaglandins (SH)

Fatty acid-like substancesFatty acid-like substances Produced in prostateProduced in prostate

small amounts producedsmall amounts producedin all tissuein all tissue

Synthesized fromSynthesized fromArachidonic AcidArachidonic Acid

COOH

CH3

Arachidonic Acid

COOH

O

HO OH

CH3

PGE2 (a prostaglandin)

steps

ProstaglandinsProstaglandins

PGEPGE2 (pg e synthesse)2 (pg e synthesse) induce laborinduce labor therapeutic abortiontherapeutic abortion lowers bplowers bp used to treat asthmaused to treat asthma

PGEPGE22 causes hypertensioncauses hypertension

COOH

O

HO OH

CH3

PGE2 (a prostaglandin)

Occurrence & Occurrence & Function ofFunction of

ProstaglandinsProstaglandins

ThromboxanesThromboxanes

O

O

OH

COOH

•When a blood vessel is ruptured, platelets congregate(together) and PGH2 causes Them to clot.

Aspirin blocks the effect and acts A blood thinner

PGH2

Prostaglandins / Prostaglandins / LeukotrieneLeukotriene

LeukotrienesLeukotrienes Occur mainly in leukocytes (white Occur mainly in leukocytes (white

blood cells)blood cells) Long lasting muscle contractions Long lasting muscle contractions

especially in the lungs where they especially in the lungs where they cause Asthma-like attackscause Asthma-like attacks

CH3

OH OHOH

COOH

Leukotriene B4

Prepared by : WALEED QADAR &MARIA IMATIAZ

Edited by : YASIR ALI & ASIF GHAFOOR.

Specially Thanx to,Madam Shabeena Gul.