lipids

Esters of fatty acids with various alcohols.

simple

alcohol + fatty acids + other groups

complex

Products of hydrolysis (breakdown) of both simple and complex lipids.

derived

fats, oils, waxes

simple

phospholipids, glycolipids

complex

fatty acid, glycerol, sterols, eicosanoids, ketones

derived

Short Chain Fatty Acids

6-12 carbons

Medium Chain Fatty Acids

13-21 carbons

Long Chain Fatty Acids

>21 carbons

Very Long Chain Fatty Acids

Small intestine and colon

Short Chain Fatty Acids

Mitochondria

Medium Chain Fatty Acids

“Lahat (mostly)”; utilized by most tissues

Long Chain Fatty Acids

“Very special”; requires peroxisomal processing before full oxidation in the mitochondria

Very Long Chain Fatty Acids

Hydrocarbon chain only contains SINGLE BONDS

Forms a STRAIGHT, LINEAR CHAIN

saturated fatty acids

Hydrocarbon chain contains ONE OR MORE DOUBLE BONDS

unsaturated fatty acids

SAME SIDE OF THE CARBON CHAIN

This creates a BEND or a KINK

occurs more in nature

Cis config

OPPOSITE SIDE OF THE CARBON CHAIN

This creates a LINEAR CHAIN ARRANGEMENT, allowing for tighter packing of molecules (similar to saturated FAs).

Trans config

USUALLY LIQUID AT ROOM TEMP

Cis config

Too much artificial trans fats in diet ⟶ increased risk of ATHEROSCLEROSIS

Trans config

no. of carbons:

ABvC

2,4,5,6

no. of carbons:

LaMyPaSta

12,14,16,18

MONOENOIC

16:1:9

Palmitoleic

MONOENOIC

18:1:9 (Cis)

Oleic

MONOENOIC

18:1:9 (Trans)

Elaidic

DIENOIC

w6 18:2:9,12

Linoleic

DIENOIC

18:3:6,9,12

y Linolenic

DIENOIC

w3 18:3:9,12,15

a Linolenic

Polyunsaturated fatty acids that the human body cannot synthesize and therefore must be obtained from the diet.

essential FA

Precursor of arachidonic acid →eicosanoids (PGs, TXs, LTs); maintains skin barrier

Linoleic Acid

Precursor of EPA and DHA → antiinflammatory eicosanoids, brain and retina function

a Linolenic Acid

Arachidonic Acid is

CONDITIONALLY ESSENTIAL

storage lipid

triacylglycerols

membrane lipid

glycerophospholipids, phospholipids,sphingolipids

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TRIACYLGLYCEROLS

Esters of glycerol (trihydric alcohol) + 3 fatty acids.

TRIACYLGLYCEROLS

Highest energy density among macronutrients.

TRIACYLGLYCEROLS

Primary energy reserve stored in adipose tissue

TRIACYLGLYCEROLS

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GLYCEROPHOSPHOLIPIDS

Glycerol backbone + 2 FAs + Phosphate + Head Group

GLYCEROPHOSPHOLIPIDS

Major component of cell membranes.

GLYCEROPHOSPHOLIPIDS

Most abundant phospholipid in cell membranes.

GLYCEROPHOSPHOLIPIDS

Deficiency: Neonatal Respiratory Distress Syndrome (NRDS)

PhosphatidylCHOLINE (LECITHIN)

Acts in cell signaling and membrane trafficking.

PhosphatidylINOSITOL

Apoptotic signal (“eat me” signal)

PhosphatidylSERINE

Stabilizes ETC and ATP synthase Serves as the antigen in VDRL/RPR

Cardiolipin (Phosphatidylglycerol/Diphosphatidylglycerol)

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ETHER GLYCOLIPIDS

Like glycerophospholipids, but one fatty acid is attached via an ether linkage instead of an ester.

ETHER GLYCOLIPIDS

examples are Plasmalogens, Platelet-Activating Factor (PAF)

ETHER GLYCOLIPIDS

Contain an unsaturated alkyl (ether) group at C1 of glycerol.

Plasmalogens

Ether linkage at C1 (saturated alkyl group). Acetyl group (not FA) at C2

PAF

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SPHINGOPHOSPHOLIPIDS

Sphingosine + FA (ceramide) + phosphate + head group

SPHINGOPHOSPHOLIPIDS

SPHINGOMYELIN - Important constituent of MYELIN SHEATH of nerve fibers.

SPHINGOPHOSPHOLIPIDS

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GLYCOLIPIDS

Sphingosine + FA (ceramide) + sugar

GLYCOLIPIDS

cerebroside, globoside, sulfatides, gangliosides

GLYCOLIPIDS

monosaccharide (glu or gal)

cerebrosides

intermediate in synthesis of complex sphingolipids

glucosylceramide (GluCer)

major glycosphingolipid of brain/myelin (precursor of sulfatides)

galactosylceramide (GalCer)

oligosaccharide

Found in RBC membranes and viscera; blood group antigens derived from them

globosides

complex; cholera toxin receptor

GM1

complex lipid:

Phosphatidylcholine (lecithin)

glycerophospholipids

complex lipid:

Phosphatidylethanolamine

glycerophospholipids

complex lipid:

Phosphatidylinositol bisphosphate

glycerophospholipids

complex lipid:

Phosphatidylglycerol / cardiolipin

glycerophospholipids

complex lipid:

Plasmalogens

ether glycolipids

complex lipid:

Platelet-Activating Factor (PAF)

ether glycolipids

complex lipid:

SPHINGOMYELIN

sphingophospholipids

complex lipid:

Cerebroside (GluCer, Galcer)

glycolipids

complex lipid:

Globoside

glycolipids

complex lipid:

Sulfatide

glycolipids

complex lipid:

Ganglioside (GM1, GM3)

glycolipids

3 SIX-MEMBERED RINGS (RING A,B,C) + 1 FIVE MEMBERED RING

cholesterol

Confers membrane fluidity and stability

cholesterol

cholesterol carbon: Hydroxyl (-OH) group; confers slight polarity

C3

cholesterol carbon: Contains a double bond

C5-C6

cholesterol carbon: Where the aliphatic side chain attaches

C17

cholesterol carbon: Contains methyl groups

C10 +C13