Key Terms Flashcards
Oil
A lipid that is liquid at room temperature
Lipid
Organic molecule that is relatively insoluble in water and soluble in organic solvents
Fat
A type of lipid that is solid at room temperature
Fatty Acid
A type of lipid consisting of a chain of carbons with a methyl (CH3) group on one end and a carboxyl acid group (COOH) on the other. A fatty acid can either be a “free” fatty acid, or can be attached to another molecule
“Free” Fatty Acid
A fatty acid that is not attached to another molecule
alpha end
The end of a fatty acid, which consists of (COOH)
Delta end
Another name for the alpha (COOH) end
Omega End
The end of the fatty acid chain, which consist of (CH3) group
Chain Length
the number of C in a fatty acid’s backbone
Short-chain FA
s
Medium chain FA
8-12 C’s
Long chain FA
> 12 C’s
Saturated FA
A FA that consists only C-C single bonds
Unsaturated FA
A FA that consist at least one C=C
Monounsaturated FA
Consists of one C=C
Polyunsaturated FA
FA that consist of more than 1 C=C
Lauric Acid
A medium chain FA believed to contribute to increase HDL levels. Increases serum blood cholesterol more than any other FA
Myristic Acid
common saturated FA found in nutmeg butter, palm kernel oil, coconut oil, and butter fat.
Palmitic Acid
Most common saturated FA found in plants and animals. Consumption is believed to increase the risk for cardiovascular disease.
Stearic Acid
saturated FA that contains an 18C chain and is currently believed to lower LDL cholesterol
Oleic Acid
a naturally-cooking unsaturated FA that is thought to decrease LDL cholesterol and increase HDL cholesterol
Cis double bond
A C-C double bond in which the H’s are located on opposite sides of the double bonds
Trans double bond
A C=C in which H’s are located on the same side of the double bond
Elaidic Acid
A primary trans FA found in hydrogenated vegetable oils, goat and cow’s milk, and some meats. Responsible for lowering HDL cholesterol.
Partial Hydrogenation
Process whereby some C=C found in PUSAs are converted to C-C, resulting in the production of a lipid containing saturated and trans fatty acid.
Omega-3 FA
The first double bond is located between the 3 and 4 C’s from omega end (CH3)
Omega-6 FA
The first double bond is located b/t the 6 and 7 C’s from the omega end (CH3)
Linoleic Acid
w-6 FA with 18 C’s and 2 double bonds
Gamma-Linolenic Acid (GLA, 18C)
18 C FA found in primarily in vegetable oil
Linolenic Acid
w-3 acid 18 C’s and 3 double bonds
Elongation
Process whereby C’s are added to FA, increasing chain length
Desaturation
The process whereby C-C single bonds are C=C bonds in FA’s
Desaturase
Enzyme that can insert a (cis) double bond in a FA by removing two H’s from an adjacent pair of C’s
Arachidonic Acid
a long chain, PU v-6 FA produced from linoleic acid
Eicosapentaenoic Acid (EPA)
long chain, PU w-3 FA produced from linolenic acid
Docosahexaenoic Acid (DHA)
a long-chain PU w-3 FA produced from EPA
Eicosanoids
Biologically active compounds - prostaglandins, prostacyclins, thromboxanes, and leukotrienes- synthesized from arachidonic acid and EPA, which are produced from both LA (n-6) ALA (n-3)
Postaglandins
a group of eicosanoids involved in regulation of blood pressure; there are both v-6 and v-3 prostaglandins, having somewhat opposite effects
Prostaglandin I2 (prostacyclin)
an eicosanoid that inhibits platelet activation. Prostacyclin is also an effective vasodilator.
Prostaglandin I3
An eicosanoid that inhibits platelet aggregation. Prostaglandin I3 is a potent vasodilator
Thromboxane A2
eicosanoids that are produced by activated platelets. They stimulate activation of new platelets and increase platelet aggregation.
Vasoconstriction
Narrowing of blood vessels that results from the contraction of the muscular walls of the blood vessels
Vasodilation
Narrowing of blood vessels that results from the relaxation of the muscular walls of the blood vessels
Platelet aggregation
the clumping together o platelets in the blood
Pro-inflammatory
a substance that causes inflammation in the body
Prothrombotic
substance that can lead to an obstruction of one or more blood vessels. Thrombi are also called clots
Anti-inflammatory
substance that decrease inflammation in the body
anti-thrombotic
a substance that decreases the risk of thrombi in the body
Ester bond
an ester is a chemical compound derived from either an organic or inorganic acid. At least one -OH group has been replaced by an O-alkyl group. Esters are typically derived from a COOH group and an alcohol. They are found in most naturally-occurring oils. An ester bond is formed b/t the acid and the O-alkyl group
Esterify
to combine a substance with either an alcohol or an acid to form an ester bond
De-esterify
to remove ester groups
Triglyceride
a lipid composed of a glycerol molecule bonded to three fatty acids
Diglyceride
a lipid made of a glycerol molecule bonded to two fatty acids
Monoglyceride
a lipid made of a glycerol molecule bonded to a single FA
Phospholipid
A type of lipid composed of a glycerol bonded to two FA and a polar head
Polar head group
a phosphate-containing charged chemical structure that is a component of a phospholipid
Polar molecule
a molecule such as water, that has both positively and negatively charged portions
Hydrophilic substance
one that dissolves in or mixes with water
Nonpolar molecule
one that does not have differently charged portions
hydrophobic substance
one that does not dissolve in or mix with water
Amphipathic
both nonpolar (noncharged) and polar (charged) portions
Phosphatidylcholine (lecithin)
A phospholipid that contains choline as its polar head group; commonly added to foods as an emulsifying agent
Sterol
type of lipid with a distinctive mutli-ring structure; a common example is cholesterol
sterol ester
chemical compound consisting of a sterol molecule bonded to a FA via ester linkage
Cholesterol
a sterol found in animal foods and made in the body; required for bile acid and steroid hormone synthesis
Cholesteryl Ester
a sterol ester made of a cholesterol molecule bonded to a FA via an ester linkage
Steroid hormone
a hormone made from cholesterol
Phytostanol
sterol-like compound made by plants
Lipases
enzymes; in the mouth, stomach, small intestine, that cleave FA from the glycerol backbone of TAGs, phospholipids, and cholesteryl esters
Lingual lipase
enzyme; produced in the salivary glands, that hydrolyzes ester linkages b/t FA and glycerol molecules. Lingual Lipases hydrolyze aa single FA from a triglyceride form a Diglyceride and a FA.
Gastric lipase
enzyme; produced in the stomach, that hydrolyzes ester linkage b/t FA and glycerol molecules. Gastric lipases hydrolyzes a single FA from a triglyceride to form a diglyceride and a free FA
Bile Acid
amphipathic substance made from cholesterol in the liver, a component of bile important for lipid digestion and absorption. Bile acids emulsify large lipid globules into smaller lipid droplets referred to as micelles.
Emulsification
the process whereby large lipid globules are broken down aand stabilized into smaller lipid droplets
Micelle
a water-soluble, spherical structure formed in the small intestine via emulsification
Micellar solubilizaation
the formation of lipids in the micelle allows for the uptake of lipids across the unstirred water layer into the enterocyte. The “solubilization” is essential for moving the hydrophobic lipids across the water layer.
Unstirred layer
layer of water b/t the intestinal lumen and the enterocyte
Pancreatic lipase
enzyme, produced in the pancreas, that hydrolyzes ester linkages b/t FA and glycerol molecules. Pancreatic lipase hydrolyze triglycerides into Monoglyceride and two free FA
Phospholipase A2
enzyme; produced in the pancreas, that hydrolyzes FA from phospholipids
Lysophopholipid
lipid composed of a glycerol bonded to a polar head group and a FA; one of the final products of phospholipid digestion
Bile Salt-Dependent Cholesteryl Ester Hydrolase
enzyme, produced in the pancreas that cleaves FA from cholesteryl esters
Enterohepatic circulation
Circulation b/t the small intestine and the liver used to recycle compounds such as bile. Ex: bile leaves the small intestine and travels back to the liver via the portal vein, allowing for recycling bile
Albumin
Protein important for regulating fluid balance b/t intravascular and interstitial spaces. This protein is also involved in transporting “free” FA and other molecules in the blood
Exogenous lipids
Originating from outside (dietary lipids)
Endogenous lipids
Originating within (in the liver)
Chylomicron
lipoprotein, made in the enterocyte, that transports exogenous lipids (mostly TAGs) from the small intestine to other tissues in the body. Chylomicrons contain apolipoproteins, one of which is apo B-48 that is specific to chylomicrons
Chylomicron Remnant
lipoprotein particle that remains after a chylomicron has lost most of its FA’s
Lipoprotein
a spherical particle made of varying amounts of triglycerides, cholesterol, cholesteryl esters, phospholipids and proteins
Apolipoprotein (Apo)
proteins embedded in the surface of lipoproteins
Lipoprotein lipase
enzyme, hydrolyzes the ester linkage b/t FA and glycerol in a triglyceride, Diglyceride and Monoglyceride molecules. The triglycerides are coming from lipoproteins as they circulate in the blood to extra-hepatic tissues.
Extra-hepatic tissue
tissue originating outside of the liver (tissue other than the liver)
Very Low Density Lipoprotein (VLDL)
a lipoprotein, made in the liver, transports endogenous lipids (mostly TAGs) from the liver to other tissues in the body. VLDL contain apolipoproteins, one of which is apo B-100. Intermediate-density lipoprotein (IDL) is a lipoprotein that results from the loss of fatty acids from VLDL, many IDLs are ultimately converted to LDLs.
Low-Density Lipoprotein (LDL)
lipoprotein, delivers cholesterol to cells
Endocytosis
process by which cells absorb molecules (proteins) by engulfing them
LDL receptor
membrane-bound protein that binds LDLs, causing them to be taken up and dismantled
Exocytosis
process in which an intracellular vesicle moves to the plasma membrane and subsequent fusion of the vesicular membrane and plasma membrane ensues
Plaque
complex cholesterol, FA, cells, cellular debris, calcium that can form inside blood vessels and within vessel walls
high-density lipoprotein (HDL)
lipoprotein, made primarily by the liver that circulates in the blood to collect excess cholesterol from cells
reverse cholesterol transport
process whereby HDLs remove free cholesterol from nonhepatic (nonliver) tissues and transport to the liver.
ACAT (Acyl- CoA Cholesterol Acyltransferase)
enzyme; that catalyzes the esterification of a free FA to a molecule of free cholesterol to form cholesterol ester
LCAT (lecithin: cholesterol acetyltransferase)
enzyme; that catalyses the remove of a FA from a surface phospholipid of HDL, esterifying it to a molecule of free cholesterol to form cholesterol ester
hypercholesterolemia
elevated levels of cholesterol in the blood
Lipolysis
the breakdown of TAGs into FA and glycerol
Lipogenesis
the metabolic process that result in FA and ultimately triglyceride sythesis
De novo lipogenesis
FA synthesis that occurs primarily in the liver and adipose tissue from precursor acetyl CoA
Adipose triglyceride lipase (ATGL)
an enzyme, that catalyzes the hydrolysis of ester linkage between a FA and glycerol of a triglyceride molecule to form a free FA and diglyceride (TG->DG and FFA)
Hormone sensitive lipase (HSL)
enzyme, that catalyzes the hydrolysis of ester linkage that attach FA’s to the glycerol molecule; mobilizes FA’s stored in adipose tissue. this enzyme catalyzes the hydrolysis of ester linkage b/t a FA and glycerol from a Diglyceride to form a FFA and a monoglyceride
Monoglyceride lipase (MGL)
enzyme that catalyzes the hydrolysis of ester linkage b/t a FA and glycerol of a monoglyceride molecule to form a FFA and glycerol molecule
adipocyte
a specialized cell that makes up the majority of adipose tissue. subcutaneous adipose tissue adipose tissue found directly under skin. visceral adipose tissue adipose tissue surrounding the vital organs
mobilization
the breakdown of adipose and intramuscular triglyceride
circulation
the transport of FA in the blood on albumin; from adipose to the muscle
delivery/uptake
the entry of FA into muscle from the blood
Lipoprotein lipase
enzyme, the hydrolyzes the ester linkage b/t a FA and glycerol in a triglyceride, diglyceride and monoglyceride molecule as they circulate in the bloodstream
esterification
a reaction with an alcohol and an acid to produce an ester (carboxylic end of a FA forming a bond with glycerol)
lipases
enzymes, that cleave FA from the glycerol backbones of triglycerides, phospholipids and cholesteryl esters
activation
raising the energy level of FA preparatory to catabolism. this is done by attaching a CoA molecule to the fatty acid to form acyl-Coa
coenzyme a (CoA)
a molecule that is involved in many metabolic pathways in the body. example this molecule is involved in both the oxidation and synthesis of FA
Translocation
Entry of activated FA into mitochondria
Beta-oxidation
the series of chemical reactions that break down activated FA’s to molecules of acetyl-Coa and the production of reducing equivalents (NADH and FADH)
Mitochondrial oxidation
krebs cycle and electron transport chain activity
carnitine
a molecule that transports FA across the mitochondrial membrane
carnitine acyltransferase I (CAT-I)
a mitochondrial enzyme also known as CPT-I, involved in FA entry into the mitochondria to undergo beta-oxidation, that attaches a carnitine onto FA. this ensyme is allosterically inhibited by malonyl CoA
Carnitine acyltransferase II (CAT-II)
mitochondrial enzyme,, involved in the removal of the carnitine group from acyl-cartinine and attaching a CoA to form acy-CoA. The fate of the acyl-CoA is beta-oxidation.
oxidation
the first and third step of beta-oxidation. this involves the removal of 2 H’s to form FADH2 (first step), and the removal of a H to form NAHD (third step)
Hydration
the second step of beta-oxidation. this involves attaching H2O to the FA
Thiolysis
The last (fourth) step of beta-oxidation. this involves adding CoA and the cleaving of a 2 C acetyl CoA
Malonyl CoA
A three C intermediate in lipogenesis which is formed by acetyl CoA
Ketosis
Accumulation of ketones in body tissues and fluids
Ketoacidosis
rise in ketones in the body tissues and fluids
Ketogenic AA
AA that can be used to make ketones
beta-ketoacyl-CoA transferase
an enzyme required to convert ketones to acetyl-CoA to be used as a energy source. The liver lacks this enzyme and therefore cannot use ketones as an energy source
Ketogenic diets
diets very low in CHO and high in fat, used to enhance fat loss
Fed state
Postprandial period, first four hours after a meal
Post Absorptive state
4-24 hours after a meal, dietary nutrients are not being absorbed
acetyl CoA carboxylase
enzyme, that carboxylates aacetyl CoA to form malonyl CoA in the presence of CO2 and ATP. Step 1 of FA synthesis
FA synthesis
enzyme, with multiple domains that is involved in the formation of a FA chain from malonyl CoA. This process requires NADPH.
Alpha-Keto Acid
The structure remaining after the amino group has been removed from an AA
Transmination
the process whereby an amino group is formed via the transfer of an amino group from one AA to another organic compound
Deamination
the removal of the amino group from an AA that results in the formation of an a-keto acid
Chronic inflammation
a response to cellular injury that is characterized by chronic capillary dilation, white blood cell infiltration, release of immune factors, redness, heat and pain
C-reactive protein (CRP)
A protein produced in the liver, adipose tissue, and smooth muscles in response to injury or infection that, when elevated, canindicate risk for cardiovascular disease
Angina Pectoris
Pain in the region of the heart, caused by a portion of the heart muscle receiving inadequate amounts of blood
Heart Attach
life-threatening, the blood flow to some or all of the heart msucle is completely blocked
Electrocardiogram
Procedure during which the heart’s electrical activity is recorded
Echocardiogram
Visual image, produced using ultrasound waves, of the heart’s structures and movements
Aniogram
procedure in which dye is injected into the blood, allowing the flow of blood through cardiac arteries to be visualized
Cardiovascular disease
disease of the heart or vascular system
Stent
a device made of rigid wire mesh that is threaded into an atherosclerotic blood vessel to expand and provide support for a damage artery
Angioplasty
a procedure used to widen the heart’s blood vessels by inserting a stend
coronary bypass surgery
a procedure in which a healthy blood vessel obtained from the leg, arm, chest or abdomen is used to bypass blood from a disease or blocked coronary artery to a healthy one
Transient Ischemic Attach
TIA, ministroke that is caused by a temporary decrease in blood flow to the brain
Stroke
a condition that occurs when a portion of the brain does not receive enough blood, can be caused by major blood loss or a blockage in the blood supply to the brain
Blood clot
a small, insoluble particle made of blood cells and clotting factors
Aneurysm
the outward bulging of a blood vessel
Atherosclerosis
hardening and narrowing of blood vessels caused by buildup of Fatty deposits and inflammation in vessel walls
Response to injury hypothesis
hypothesis that explains injury or damage to the endothelial lining of arteries as initiating atherosclerosis
Monocyte
an immunocyte, phagocytic white blood cells that can pass through the epithelium of blood vessels and differentiate into macrophages
Macrophage
an immunocyte; phagocytic white blood cell that can engulf oxidized LDL which in turn becomes a foam cell
Foam Cell
a type of cell- using an immune cell-that contains large amounts of lipid, such as fat filled macrophages which are usually indicative of atheroecieosis
hyperlipidemia
elevated levels of lipids in the blood
hypertriglyceridemia
elevated levels of triglycerides in the blood
Cholesterol Ratio
the mathematical ratio of total blood cholesterol to high-density lipoprotein cholesterol (HDL-C)
DASH
Dietary Approaches to Stop Hypertension; dietary pattern emphasizing fruit, veggies, and low-fat products designed to lower blood pressure
Mediterranean Diet
Lowers the risk of CVD
Therapeutic lifestyle changes (TLC)
heart healthy diet recommendations put forth by the National Cholesterol Education Program
Hypertension
Chronically elevated blood pressure. Risk factor for Heart disease
Seven Countries Study
Study related to diet and lifestyle to rates of heart attach and stroke in contrasting populations
