Lipid metabolism involves the oxidation of fatty acids to produce energy. There are three main types of fatty acid oxidation: beta, alpha, and omega. Beta-oxidation occurs in the mitochondria and breaks down fatty acids into acetyl-CoA via a four-step process. Cholesterol is synthesized from acetyl-CoA in the liver through a series of reactions. Ketone bodies such as acetoacetate and beta-hydroxybutyrate are produced from acetyl-CoA in the liver during periods of low glucose and provide energy for other tissues. Lipoproteins such as chylomicrons, VLDL, LDL, and HDL are involved in transporting lipids between tissues.
Lipid metabolism entails the oxidation of fatty acids to either generate energy or synthesize new lipids from smaller constituent molecules. Lipid metabolism is associated with carbohydrate metabolism, as products of glucose (such as acetyl CoA) can be converted into lipids.
Lipid metabolism entails the oxidation of fatty acids to either generate energy or synthesize new lipids from smaller constituent molecules. Lipid metabolism is associated with carbohydrate metabolism, as products of glucose (such as acetyl CoA) can be converted into lipids.
Are most abundantly distributed organic compounds.
70 kg man= protein weight constitute 12 kg
Skeleton and connective tissue contains half
Body protein and other half is intracellular.
Lipid metabolism is the synthesis and degradation of lipids in cells.
It involves the breakdown or storage of fats for energy and the synthesis of structural and functional lipids, such as those involved in the construction of cell membranes.
In animals, these fats are obtained from food or synthesized by the liver.
Glycolysis (from glycose, an older term for glucose + -lysis degradation) is the metabolic pathway that converts glucose C6H12O6, into pyruvate, CH3COCOO− + H+. The free energy released in this process is used to form the high-energy molecules ATP (adenosine triphosphate) and NADH (reduced nicotinamide adenine ...
Are most abundantly distributed organic compounds.
70 kg man= protein weight constitute 12 kg
Skeleton and connective tissue contains half
Body protein and other half is intracellular.
Lipid metabolism is the synthesis and degradation of lipids in cells.
It involves the breakdown or storage of fats for energy and the synthesis of structural and functional lipids, such as those involved in the construction of cell membranes.
In animals, these fats are obtained from food or synthesized by the liver.
Glycolysis (from glycose, an older term for glucose + -lysis degradation) is the metabolic pathway that converts glucose C6H12O6, into pyruvate, CH3COCOO− + H+. The free energy released in this process is used to form the high-energy molecules ATP (adenosine triphosphate) and NADH (reduced nicotinamide adenine ...
Lipid metabolism is the synthesis and degradation of lipids in cells, involving the breakdown and storage of fats for energy and the synthesis of structural and functional lipids, such as those involved in the construction of cell membranes. In animals, these fats are obtained from food and are synthesized by the liver. Lipogenesis is the process of synthesizing these fats. The majority of lipids found in the human body from ingesting food are triglycerides and cholesterol.[4] Other types of lipids found in the body are fatty acids and membrane lipids. Lipid metabolism is often considered as the digestion and absorption process of dietary fat; however, there are two sources of fats that organisms can use to obtain energy: from consumed dietary fats and from stored fat.[5] Vertebrates (including humans) use both sources of fat to produce energy for organs such as the heart to function. Since lipids are hydrophobic molecules, they need to be solubilized before their metabolism can begin. Lipid metabolism often begins with hydrolysis, which occurs with the help of various enzymes in the digestive system.Lipid metabolism also occurs in plants, though the processes differ in some ways when compared to animals.[8] The second step after the hydrolysis is the absorption of the fatty acids into the epithelial cells of the intestinal wall.[6] In the epithelial cells, fatty acids are packaged and transported to the rest of the body.[9]
Metabolic processes include lipid digestion, lipid absorption, lipid transportation, lipid storage, lipid catabolism, and lipid biosynthesis. Lipid catabolism is accomplished by a process known as beta oxidation which takes place in the mitochondria and peroxisome cell organelles.
This ppt has been presented as seminar in Department of Biochemistry ,C.C.S. university, Meerut.in front of all faculty members for the detailed discussion on this topic. Hope this will help you to go through the concept in an easy manner.
Presentation on Fatty Acid Biosynthesis in cell (Creation of fatty acids from acetyl-CoA and NADPH through the action of enzymes called fatty acid synthases).
For medical students, especially for early clinical exposure , it will help preclinical medical students. It gives details of about seven case reports in carbohydrate metabolism. MBBS students can use the information for theory exam also.
For medical students , it will help. Especially for preclinical students, as early clinical exposure, it will be very useful. Even for theory exam, it will help.
Extra cellular matrix is recently being explored in connection with cancer , metastases and autoimmune disorders. It is prepared for the benefit of both UG and PG medical and dental students.
Various neurotransmitters, mechanism of action and their physiological functions are explained and is useful for ug and pg students of medicine, neurology, psychiatry branches.
Porphyrias are difficult to diagnose . Here it is comprehensively explained to aid making diagnosis of porphyrias easier for the benefit of medical students and practitioners.
Renal function tests are very useful for effective clinical evaluation of renal failure for effective management. So it is useful for medical and allied professional students and clinical practitioners.
Test for pancreatic and intestinal functions are very important for clinical evaluation gastro intestinal disorders . So it will e useful for medical and allied professional students and practitioners.
Liver function tests and interpretation is a very important topic for students of medical and allied fields. It is essential for efficient practice of clinical and laboratory medicine.
Students of medical and allied subjects must be exposed to the concept of monoclonal antibodies for the efficient practice of clinical and laboratory medicine.
Concepts of acid base balance and its disorders are very important for practice of medicine.It is for the benefit of medical and students of allied fields.
Coronary heart disease due to atherosclerotic process is the major cause of death.Lipids have been implicated for enhanced atherosclerosis. The major lipids involved are triacy glycerol and cholesterol which are transported in the plasma by lipoproteins. So a better understanding of lipid transport and its abnormalities is essential for medical and health professional students.
Water and electrolyte balance is clinically very important topic . It will be very useful for both UG and PG medical students. Efforts are made to explain basic concepts clearly.
It gives basic things regarding urinalysis and will be very useful for medical students, house surgeons, laboratory technicians and postgraduates in medicine.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
2. Oxidation of Fatty Acids
Fatty acids are an important source of
energy
Oxidation is the process where energy is
produced by degradation of fatty acids
There are several types of fatty acids
oxidation.
(1) β- oxidation of fatty acid
(2) α- oxidation of fatty acids
(3) ω- oxidation of fatty acids
3. β- oxidation of fatty acid
Beta-oxidation is the process by which fatty acids, in the
form of Acyl-CoA molecules, are broken down in
mitochondria and/or in peroxisomes to generate Acetyl-CoA –
enters TCA cycle
It occurs in many tissues including liver kidney and heart.
Fatty acids oxidation doesn't occur in the brain, as fatty acid
can't be taken up by that organ.
4. Stages
The beta oxidation of fatty acids involve
three stages:
1. Activation of fatty acids in the cytosol
2. Transport of activated fatty acids into mitochondria
(carnitine shuttle)
3. Beta oxidation proper in the mitochondrial matrix
5. 1) Activation of FA:
This proceeds by FA thiokinase (acyl COA synthetase)
present in cytosol
Thiokinase requires ATP, COA SH, Mg++. The product
of this reaction is FA acyl COA and water.
6. 2- Transport of fatty acyl CoA from cytosol into
mitochondria: ( rate-limiting step) Long chain acyl CoA traverses the inner
mitochondria membrane with a special transport
mechanism called Carnitine shuttle.
The matrix
The cytosol
7.
8. 2-Transport of acyl CoA into the mitochondria
(rate-limiting step)
1. Acyl groups from acyl COA is transferred to carnitine
to form acyl carnitine catalyzed by carnitine
acyltransferase I, in the outer mitochondrial
membrane.
2. Acylcarnitine is then shuttled across the inner
mitochondrial membrane by a translocase enzyme.
3. The acyl group is transferred back to CoA in matrix by
carnitine acyl transferase II.
4. Finally, carnitine is returned to the cytosolic side by
translocase, in exchange for an incoming acyl carnitine.
9. 3. Proper of β – oxidation in the mitochondrial
matrixThere are 4 steps in β C– oxidation
Step I – Oxidation by FAD linked dehydrogenase
Step II – Hydration by Hydratase
Step III – Oxidation by NAD linked dehydrogenase
Step IV – Thiolytic clevage Thiolase
10. The first reaction is the oxidation of acyl CoA by an
acyl CoA dehyrogenase to give α-β unsaturarted acyl
CoA (enoyl CoA).
FAD is the hydrogen acceptor.
11. The second reaction is the hydration of the double
bond to β-hydroxyacyl CoA (p-hydroxyacyl CoA).
12. The third reaction is the oxidation of β-hydroxyacyl
CoA to produce β-Ketoacyl CoA a NAD-dependent
reaction.
13. The fourth reaction is cleavage of the two carbon
fragment by splitting the bond between α and β
carbons
By thiolase enzyme.
14.
15. energetics
FADH2 - 1.5 ATP
NADH2 - 2.5 ATP
Each cycle 4 ATP
Palmitic acid – 7 cycles - 7 x 4 = 28
Acetyl CoA - 8 x 10 ATP – 80
Activation energy loss – 2 ATP
Net energy- 108 – 2 = 106 ATP
16. Regulation
The availability of fatty acids influences beta
oxidation.
Glucagon by activating hormone sensitive lipase
increases FFA level in blood
Insulin inhibits Beta oxidation by inhibiting this
enzyme.
Malonyl CoA inhibits CAT-1 activity.
17. Cholesterol biosynthesis
Location of pathway
1.The pathway is located in the
cytosol
2.Raw material Acetyl-CoA.
3.Most cells can make cholesterol,
but liver is most active.
18. Stages
1 - Synthesis of mevalonate
2. Synthesis of isopentenyl units
3. Synthesis of squalene
4.Synthesis of lanosterol
5. Synthesis of cholesterol
19. Cholesterol Biosynthesis:
Formation of Mevalonate
2 CH3COSCoA CH3COCH2COSCoA
Thiolase
CH3COSCoA
Acetoacetyl CoA
HO2C-CH2-C-CH2COSCoA
OH
CH3
-Hydroxy--methyl-
glutaryl CoA (HMG CoA)
HMG CoA
Synthase
HO2C-CH2-C-CH2CH2OH
OH
CH3
3R-Mevalonic acid
HMGCoA
reductase
CoASH
Key control step
in cholesterol
biosynthesis
Liver is primary site of cholesterol biosynthesis
27. Transformations of
Cholesterol: Bile Salts
CO2
-
HO
CH3
HO OH
H
CH3
CONHCH2R
CH3
CH3
HO
CH3
Cholesterol Cholic acid
R = CH2SO3
-
Taurocholate
R = CO2
-
Glycocholate
Detergents
28. Transformations of
Cholesterol: Steroid Hormones
O
O
O
OH
OHHO
O
CH3
HO
CH3
Cholesterol
Estradiol
Progesterone
Cortisol
O
OH
TestosteroneHO
OH
CH2
HO
OH
OH
Vitamin D
29. Factors affecting serum cholesterol
Role of Fatty acids
Effect of high fructose intake on blood lipids
Hypercholesterolemia occurs in diabetes mellitus,
Hypothyroidism, Obstructive jaundice, Familial
hypercholesterolemia.
30. Hereditary factor -In familial
hypercholesterolemia, due to LDL receptor defect,
LDL cholesterol uptake is reduced
Hypolipidemic drugs
Statins - competitive inhibitors of HMG CoA-
reductase.
Clofibrate It enhances fecal excretion of
cholesterol and bile acids and also increases the
peroxisomal oxidation of fatty acids in liver.
31. Cholestyramine This increases their excretion
bile acids in the stools.
Clofibrates, gemfibrosil lower plasma TGL by
decreasing VLDL .Activate lipoprotein lipase.
Probucol increases the catabolism of LDL. It also
has antioxidant properties
Nicotinic acid reduces lipolysis and inhibits
VLDL production.
33. Two molecules of acetyl CoA condense to form acatoacetyl
CoA by thiolase or acetoacetyl CoA synthase .
Step two: Acetoacetyl CoA condenses with another
molecule of acetyl CoA to form 3-Hydroxy-3-methyl-
glutaryl CoA (HMG-CoA) by HMG-CoA synthase enzyme.
Step three: HMG-CoA lyase cleaves HMG - CoA to
acetoacetate and acetyl CoA.
Step four: Acetoacetate is the primary ketone body.
It is reduced to beta hydroxy butyrate by beta-hydroxy
butyrate dehydrogenase using NADH+H+ as coenzyme.
Acetoacetate undergoes non enzymatic spontaneous
decarboxylation to acetone.
34. Fate of ketone bodies
3-hydroxy butyrate is the predominant ketone body
present in blood and urine in ketosis.
Liver cannot utilize ketone bodies
It lacks the particular enzyme- the CoA – transferase
or thiophorase.
Peripheral tissues utilize them.- Succinyl CoA –
acetoacetate CoA transferase or thiophorase
Succinyl CoA + acetoacetate – succinate + acetacetyl
CoA
35. Regulation
If there is increase of lipolysis, there is increase of
ketogenesis.
Insulin inhibits ketogenesis
Glucagon and norepinephrine promotes .
In diabetes mellitus , due to insulin deficiency, ketosis
occurs.
Starvation – increase of ketogenesis
36. Chylomicrons
Dietary lipid absorbed in the small intestine is incorporated into
chylomicrons which reach systemic circulation via lymphatics,
thoracic duct .
In circulation , by the action of lipoprotein lipase (LPL) ,
chylomicrons on releasing fatty acids and glycerol become
smaller in size known as chylomciron remnants.
The remnants are removed in the liver by receptor mediated
endocytosis.
Insulin increases LPL activity
In type I hyperlipoproteinemia , there is a defect in LPL leading
to fasting chylomicronemia . VLDL is also increased
Hepatomegaly, eruptive xanthoma, lipemia retinalis and
abdominal pain are characteristic features
37. Treatment
Fat diet containing short and medium chain fatty acids
High carbohydrates diet will induce VLDL synthesis
and it is to be limited
When fasting serum kept in fridge for 24 hrs, a creamy
layer on top due to chylomicrons appear and on
electrophoresis, a band at the point of application is
seen.
38. VLDL Very low density lipoproteins
They are involved in the transport of triacyglcyerol,
cholesterol produced in the liver.
LPL acts on it and releases fatty acids and glycerol on
hydrolysis of TGL
VLDL becomes IDL that contain apo B100 & apo E
Part of IDL is taken up liver via Apo B100, E receptor
Part of IDL releases TGL, apo E and becomes LDL-a
cholesterol rich, apo B100 containing lipoprotein.
39. Low density lipoprotein (LDL)
LDL transports cholesterol from liver to extra hepatic
tissues. LDL concentration positively correlates with
cardiovascular disease
LDL is taken up by LDL receptors mainly present in
liver, adrenal cortex and extra hepatic tissues .
40. Familial hypercholesterolemia
Type II a-hyperlipoproteinemia
It is due to LDL receptor defect
Serum cholesterol and LDL cholesterol are increased
where as TGL is normal on electrophoresis, beta-band
is increased
Tuberous xanthoma, atherosclerosis and early CAD.
Low cholesterol high PUFA diet and drugs such as
HMG CoA reductase inhibitors ,bile acid binding
resin are given.
41. High density lipoprotein
It is synthesized and secreted from both liver and
intestine.
Nascent HDL is discoid, phospholipid bilayer
containing apo A and free cholesterol.
Plasma enzyme LCAT (Lecithin cholesterol acyl
transferase) by activator Apo A1 bind to the disk and
esterifies cholesterol.
Non-polar cholesteryl ester forms the core and HDL
becomes spherical .
42.
43.
44. Lipid profile (Reference range)
Total serum cholesterol : 140 – 200 mg/dL
Serum LDL cholesterol – less than 100mg/dl
Serum triglycerides - 50- 150 mg/dL (Less than 100
mg/dL is optimal)
Serum HDL cholesterol - 40- 70 mg/dL
45. HDL Less than 40 mg/dL in men and less than 50
mg/dL in women increases the risk of heart
disease.
HDL more than 60 mg/dl decreases the risk of
heart disease.
LDL/HDL ratio – less than 3 is cardio protective
and more than 5 increases the risk.
Total cholesterol/ HDL ratio should be less than 5:1
. Ideal is 3.5:1.