GI Lipid Metab & Membrane Lipids MCQ's
A membrane lipid is a compound, which belongs to a group of which form the double-layered surfaces of all cells. Lipid metabolism is the synthesis and degradation of lipids in cells where fat are broken down for energy. Take up the gi lipid metab & membrane lipids MCQ's below to see how well you understood the course.
Questions and Answers
- 1.
Treatment of hypercholesterolemia requires knowledge of the control of HMG-CoA reductase activity and LDL receptor (LDLR) levels. Which of the following statements is correct concerning HMG-CoA reductase and the LDLR?
- A.
Their synthesis in the liver is increased after a meal containing cholesterol and cholesterol esters
- B.
They both contain CoA
- C.
When the LDLR is up-regulated, HMG-CoA reductase is switched on.
- D.
HMG-CoA reductase is activated when the LDLR is down-regulated and the cell requires cholesterol
- E.
Both HMG-CoA reductase and the LDLR are synthesized in response to high levels of intracellular cholesterol
Correct Answer
D. HMG-CoA reductase is activated when the LDLR is down-regulated and the cell requires cholesterolExplanation
When the LDL receptor (LDLR) is down-regulated, it means that there are low levels of LDL cholesterol being taken up by the cell. In this situation, the cell requires more cholesterol for its functions. HMG-CoA reductase is the enzyme responsible for the synthesis of cholesterol in the cell. Therefore, when the LDLR is down-regulated and the cell requires cholesterol, HMG-CoA reductase is activated to produce more cholesterol. This statement correctly explains the relationship between HMG-CoA reductase, LDLR, and cholesterol synthesis in the cell.Rate this question:
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- 2.
Inhibiting the rate limiting enzyme of cholesterol biosynthesis would be beneficiary in lowering blood cholesterol levels by one of the following mechanisms:
- A.
Increasing the conversion of cholesterol to bile acids
- B.
Inhibiting the formation of HMG-CoA
- C.
Preventing the reabsorption of bile acids from the intestine
- D.
Inhibiting the formation of mevalonate
- E.
Inhibiting the absorption of cholesterol from the diet
Correct Answer
D. Inhibiting the formation of mevalonateExplanation
Inhibiting the formation of mevalonate is beneficial in lowering blood cholesterol levels because mevalonate is a precursor molecule in the cholesterol biosynthesis pathway. By inhibiting its formation, the production of cholesterol is also inhibited, leading to lower blood cholesterol levels. Mevalonate is converted to HMG-CoA, which is further converted into cholesterol. Therefore, inhibiting the formation of mevalonate indirectly inhibits the formation of cholesterol.Rate this question:
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- 3.
Which of the following phospholipids is released by phagocytic cells and leads to superoxide radical production in alveoli macrophages?
- A.
Plasmalogens
- B.
Phosphatidylinositol
- C.
Cardiolipin
- D.
Platelet activating factor
- E.
Phosphatidylcholine
Correct Answer
D. Platelet activating factorExplanation
Platelet activating factor (PAF)
Hormone released from phagocytic cells binds to surface receptors
Causes platelets to aggregate and degranulate. It binds to surface receptors resulting in thrombotic and inflammatory events and anaphylactic reactions
Causes neutrophils and alveoli macrophages to produce superoxide radicals (useful for killing bacteria) (slide 18 Memb Lip-Laville)Rate this question:
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- 4.
A mother takes her one-year-old daughter to the pediatric clinic because she observes that the child keeps walking into objects and does not respond when she talks to her. On examination the pediatrician notes that she has problems with her hearing and cannot see. Other observations included muscle weakness and slow mental and motor development. This patient most likely has which one of the following diseases:
- A.
Tay-Sachs
- B.
Fabry
- C.
Krabbes
- D.
Neimann-Pick
- E.
Faber
Correct Answer
C. KrabbesExplanation
The patient most likely has Krabbes disease based on the symptoms described. Krabbes disease is a rare genetic disorder that affects the nervous system. It is characterized by the loss of myelin, the protective covering of nerve cells, which leads to problems with hearing and vision, muscle weakness, and delayed development. The symptoms mentioned in the question, such as walking into objects, not responding to sounds, muscle weakness, and slow mental and motor development, align with the characteristic features of Krabbes disease.Rate this question:
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- 5.
Patients with hypothyroidism also present with secondary hypercholesterolemia. One of the reasons for this is:
- A.
HMG-CoA red uctase is activated due to low levels of thyroid hormones
- B.
Low density lipoprotein receptors are upregulated in these patients
- C.
Large amounts of cholic acid are reabsorbed from the intestine which feeds back to 7-a-hydroxylase resulting in inactivation of the enzyme
- D.
High levels of thyroid hormones increase the synthesis of cholesterol
- E.
Thyroid hormones are necessary for the activation of 7a-hydroxylase
Correct Answer
E. Thyroid hormones are necessary for the activation of 7a-hydroxylaseExplanation
Cholesterol 7 alpha-hydroxylase is the rate-limiting enzyme in the synthesis of bile acid from cholesterol via the classic pathway, catalyzing the formation of 7-alpha-hydroxycholesterol. CYP7A1 is a cytochrome P450 heme enzyme that oxidizes cholesterol using molecular oxygen.
It is downregulated by Sterol regulatory element-binding proteins (SREBP) when plasma cholesterol levels are low. It is upregulated by the nuclear receptor LXR (liver X receptor) when cholesterol (to be specific, oxysterol) levels are high.[2]
The effect of this upregulation is to increase the production of bile acids and reduce the level of cholesterol in hepatocytes.Rate this question:
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- 6.
A deficiency in the activity of medium chain acyl-CoA dehydrogenase, an enzyme in the pathway for beta-oxidation of fatty acids, is corrected by large doses of its vitamin component in some patients. Which of the following compounds is the vitamin component of this enzyme?
- A.
Carnitine
- B.
Vitamin E
- C.
Riboflavin
- D.
Niacin
- E.
Thiamine
Correct Answer
C. RiboflavinExplanation
The signs and symptoms of riboflavin deficiency typically include sore throat with redness and swelling of the mouth and throat mucosa, cheilosis and angular stomatitis (cracking of the lips and corners of the mouth), glossitis (magenta tongue with atrophy), seborrheic dermatitis or pseudo-syphilis (moist, scaly skin particularly affecting the scrotum or labia majora and the nasolabial folds), and a decreased red blood cell count with normal cell size and hemoglobin content (normochromic normocytic anemia).
Persons with chronic alcoholism can have impaired absorption of riboflavin and other vitamins such as thiamine (see Wernicke's encephalopathy).
USMLE step 1 book indicates that corneal vascularization is also a presentation for B2 deficiency.Rate this question:
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- 7.
A patient presents to your clinic complaining of weakness and pain in the muscle and a general lack of energy. A blood test shows that he has high levels of creatine kinase and myoglobin. Urine analysis reveals very low levels of acetoacetate. This patient most likely has which of the following?
- A.
Complete absence of medium chain acyl-CoA dehydrogenase
- B.
Deficiency in one of the enzymes in the ketone body synthetic pathway
- C.
Carnitine deficiency
- D.
A low fat, high carbohydrate diet
- E.
Decreased production of insulin
Correct Answer
C. Carnitine deficiencyExplanation
Diseases of carnitine shuttle
Systemic primary carnitine deficiency: SLC22A5 gene on chromosome 5q31.1, renal re-uptake transporter OCTN2 (Na+-cotransport). Frequency Faroe Islands 1 in every 500, otherwise 1 in several 10000. OMIM #212140.
Hypoketotic hypoglycemia, Reye-syndrom like episodes, lethargy, somnolence, hepato- and cardiomegaly.
Treatment: oral supplementation of carnitine
Carnitine palmitoyltransferase I deficiency: hypoketotic hypoglycemia, Reye-syndrom like episodes,
hepatomegaly, muscle weakness. OMIM #255120.
Treatment: prevent hypoglycemia with short- and medium-chain fa in diet
Carnitine-acylcarnitine translocase deficiency: Presents within hours of birth with seizures, bradycardia, breathing problems, hypoketotic hypoglycemia, hyperammonemia, hepatomegaly, cardiomyopathy, muscle weakness, sudden infant death. OMIM #212138.
Treatment: low lipid intake, medium chain fa, carnitine, avoid strenuous exercise.
Carnitine palmitoyltransferase II deficiency: Three forms:
Adult: OMIM #255110. Muscle problems (myalgia, rhabdomyolysis, myoglobinuria) during attacks, otherwise normal. Attacks induced by exercise, fasting, high-fat diet, infection. Highly variable age of onset, | more strongly affected.
Infantile: OMIM #600649. Age of onset usually _ 1a, but sometimes later. Hypoketotic hypoglycemia, loss of consciousness and seizures, hepato- and cardiomegaly.
Neonate: OMIM #608836. Onset hours to days after birth, rapidly fatal from cardiac, respiratory or liver failure.
Neuronal migration defects, kidney dysorganization. carnitine formed in liver and kidney from Lys and Met
supplementation not required in healthy individual 12 C-atoms pass membrane by diffusion
distribution of acyl-CoA between cytosol (anabolic) and mito (catabolic)
rate-limiting step of FA breakdown! ( slide 20-22 F.A metab-BUX)Rate this question:
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- 8.
During starvation ketone bodies are synthesized in one of the following organs:
- A.
Skeletal muscle
- B.
Spleen
- C.
Liver
- D.
Heart
- E.
Brain
Correct Answer
C. LiverExplanation
During starvation, the body undergoes a process called ketogenesis, where ketone bodies are synthesized as an alternative fuel source. The liver plays a crucial role in this process as it is responsible for the production of ketone bodies. The liver breaks down fatty acids into ketone bodies, such as acetoacetate and beta-hydroxybutyrate, which can be used by various tissues, including the brain and muscles, for energy. Therefore, the liver is the organ where ketone bodies are synthesized during starvation.Rate this question:
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- 9.
A 29-year-old male decides to go on the Atkins diet. After approximately a month on the diet he complains of having what he describes as bad breath. What would be the biochemical findings in this patient?
- A.
Increased synthesis of fatty acids in adipose tissue due to excess free fatty acids released from adipose tissue
- B.
Decreased gluconeogenesis due to lack of activation of pyruvate carboxylase
- C.
Decreased levels of free fatty acids and undetectable ketone bodies in the plasma due to inactivation of LPL
- D.
Increased synthesis and recycling of fatty acids by the liver leading to increased adipose tissue storage of fats
- E.
Increased beta-oxidation due to increased activity of hormone sensitive lipase with subsequent increase in ketone bodies in plasma
Correct Answer
E. Increased beta-oxidation due to increased activity of hormone sensitive lipase with subsequent increase in ketone bodies in plasmaExplanation
When following the Atkins diet, the body enters a state of ketosis where it relies on fat for energy instead of carbohydrates. This leads to increased beta-oxidation, the process by which fatty acids are broken down to produce energy. As a result, there is an increase in the production of ketone bodies, which are byproducts of fat metabolism. One of the symptoms of ketosis is bad breath, known as "ketone breath." Therefore, the biochemical findings in this patient would be increased beta-oxidation with subsequent increase in ketone bodies in the plasma, explaining the symptom of bad breath.Rate this question:
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- 10.
What is the importance of citrate in fatty acid metabolism?
- A.
Activation of fatty acid synthetase
- B.
To act as a precursor for addition of one carbon units
- C.
Activation of acetyl-CoA carboxylase
- D.
To add the activated carbon dioxide in the formation of malonyl-CoA
- E.
Activation of carnitine acyl transferase
Correct Answer
C. Activation of acetyl-CoA carboxylaseExplanation
FA synthesis and b-oxidation must not occur at the same time (futile cycle)
Compartmentalization: FA synthesis in cytosol, breakdown in mitocondria
Malonyl-CoA (substrate for FA synthesis) shuts down carnitine shuttle (rate-limiting step of FA breakdown)
FA synthesis regulated at acetyl-CoA carboxylase:
citrate signals good nutrition: allosteric
insulin=dephosphorylation=activation
glucagon + adrenalin=inc cAMP =phosphorylation=
inactivation
gene expression: insulin", glucagon#
( slide 57 F.A metab-BUX)Rate this question:
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- 11.
The reducing equivalents necessary for fatty acid synthesis are produced during the conversion of:
- A.
Glyceraldehyde-1, 3-bisphosphate to 3-phosphoglycerate
- B.
Glucose-6-phosphate to ribulose-5-phosphate
- C.
Glucose-6-phosphate to fructose-6-phosphate
- D.
Citrate to malate
- E.
Pyruvate to lactate
Correct Answer
B. Glucose-6-phosphate to ribulose-5-phosphateExplanation
During the conversion of glucose-6-phosphate to ribulose-5-phosphate in the pentose phosphate pathway, NADPH is produced. NADPH is a reducing equivalent and is required for fatty acid synthesis. Therefore, this conversion provides the necessary reducing equivalents for fatty acid synthesis.Rate this question:
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- 12.
When excess acetyl-CoA, produced by the liver, cannot be used by the TCA cycle, it accumulates in the body as:
- A.
Glucose
- B.
Triglycerides
- C.
P-hydroxybutarate
- D.
Acetyl-CoA
- E.
Glycogen
Correct Answer
C. P-hydroxybutarateExplanation
When excess acetyl-CoA cannot be utilized by the TCA cycle, it is converted into p-hydroxybutarate. This conversion occurs in the liver and is part of a metabolic pathway known as ketogenesis. p-hydroxybutarate is one of the ketone bodies produced during this process. Ketone bodies can be used as an alternative fuel source by various tissues, including the brain, when glucose availability is limited. Therefore, when excess acetyl-CoA accumulates, it is converted into p-hydroxybutarate to be used as an energy source.Rate this question:
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- 13.
Which of the following disorders of glucocerebrosidase metabolism can be treated by bone marrow transplant?
- A.
Fabrys
- B.
Tay-Sachs
- C.
Nieman-Pick
- D.
Gauchers
- E.
Krabbes
Correct Answer
D. GauchersExplanation
Successful bone marrow transplantation cures the non-neurological manifestations of the disease, because it introduces a monocyte population with active beta-glucosidase.
Nieman pick = sphingomylenRate this question:
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- 14.
Which of the following organelles, which is defective in Gauchers disease, contains enzymes that degrade complex carbohydrates, proteins and complex lipids?
- A.
Lysosome
- B.
Peroxisome
- C.
Mitochondrion
- D.
Endoplasmic reticulum
- E.
Plasma membrane
Correct Answer
A. LysosomeExplanation
Gaucher's disease is a genetic disease in which lipids accumulates in cells and certain organs. Gaucher's disease is the most common of the lysosomal storage diseases. It is characterized by bruising, fatigue, anemia, low platelets, and enlargement of the liver and spleen. It is caused by a hereditary deficiency of the enzyme glucosylceramidase. The enzyme acts on the fatty acid glucosylceramide. When the enzyme is defective, glucosylceramide accumulates, particularly in white blood cells, most often macrophages (mononuclear leukocytes). Glucosylceramidase can collect in the spleen, liver, kidneys, lungs, brain and bone marrow.
Symptoms may include enlarged spleen and liver, liver malfunction, skeletal disorders and bone lesions that may be painful, severe neurologic complications, swelling of lymph nodes and (occasionally) adjacent joints, distended abdomen, a brownish tint to the skin, anemia, low platelets and yellow fatty deposits on the sclera. Persons affected most seriously may also be more susceptible to infection. Some forms of Gaucher's disease may be treated with enzyme replacement therapy.Rate this question:
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- 15.
Some of the apoproteins have very important functions in lipoprotein metabolism. Which of the following apoproteins is an important activator of lecithin cholesterol acyl transferase (LCAT)?
- A.
Apo All
- B.
Apo Al
- C.
Apo CII
- D.
Apo AIV
- E.
Apo E
Correct Answer
B. Apo AlExplanation
Apo Al is an important activator of lecithin cholesterol acyl transferase (LCAT).Rate this question:
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- 16.
Prostaglandins are synthesized from which of the following essential fatty acids?
- A.
Linolenic acid
- B.
Linoleic acid
- C.
Arachidonic acid
- D.
Ecosapentanoic acid
- E.
Palmitic acid
Correct Answer
A. Linolenic acidExplanation
Prostaglandins are synthesized from linolenic acid, an essential fatty acid. Linolenic acid is converted into other fatty acids, such as arachidonic acid, which then serve as precursors for prostaglandin synthesis. Prostaglandins are important signaling molecules that play a role in various physiological processes, including inflammation, blood clotting, and smooth muscle contraction.Rate this question:
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- 17.
In patients with systemic lupus erythematosus, autoantibodies are produced to a membrane lipid in platelets, resulting in blood clotting disorders. This membrane lipid is:
- A.
Phosphatidylserine
- B.
Cardiolipin
- C.
Phosphatidyl inositol
- D.
Dipalmitoylphosphatidylcholine
- E.
Platelet activating factor
Correct Answer
B. CardiolipinExplanation
Cardiolipin: Found in abundance in the inner mitochondrial membrane where it maintains certain respiratory complexes on the electron transport chain
The only human glycerophospholipid that is antigenic. It is recognized by antibodies raised against Trepanoma Pallidum. = Autoimmune diseases.
(slide 13 Memb Lip-Laville)
Cardiolipin from a cow heart is used as an antigen in the Wassermann test for syphilis. Anti-cardiolipin antibodies can also be increased in numerous other conditions, including systemic lupus erythematosus, malaria and tuberculosis, so this test is not specific. (wikipedia)Rate this question:
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- 18.
A 5-year old female is presented with hepatosplenomegaly, abnormal bleeding disorders, defects in long bone development and neurological dysfunction. Laboratory analysis of a liver biopsy reveals that the patient has only 30 % activity of the enzyme glucoceribrosidase. This patient most likely is suffering from one of the following diseases:
- A.
Fabrys
- B.
Sandhoff-Jatzkewitz
- C.
Krabbes
- D.
Gauchers
- E.
Neimann-Pick
Correct Answer
D. GauchersExplanation
Symptoms may include enlarged spleen and liver, liver malfunction, skeletal disorders and bone lesions that may be painful, severe neurologic complications, swelling of lymph nodes and (occasionally) adjacent joints, distended abdomen, a brownish tint to the skin, anemia, low platelets and yellow fatty deposits on the sclera. Persons affected most seriously may also be more susceptible to infection. Some forms of Gaucher's disease may be treated with enzyme replacement therapy.
Gaucher's disease is a genetic disease in which lipids accumulates in cells and certain organs. Gaucher's disease is the most common of the lysosomal storage diseases. It is characterized by bruising, fatigue, anemia, low platelets, and enlargement of the liver and spleen. It is caused by a hereditary deficiency of the enzyme glucosylceramidase. The enzyme acts on the fatty acid glucosylceramide. When the enzyme is defective, glucosylceramide accumulates, particularly in white blood cells, most often macrophages (mononuclear leukocytes). Glucosylceramidase can collect in the spleen, liver, kidneys, lungs, brain and bone marrow.Rate this question:
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- 19.
A 22-year-old woman with poorly controlled gestational diabetes delivers a large -forgestational-age infant at 24 weeks. Within six hours of birth the baby develops respiratory difficulties associated with rapid respiration and cyanosis. Which of the following substances is most likely deficient in this newborn?
- A.
Cardiolipin
- B.
Ceramide
- C.
Sphingomyelin
- D.
Dipalmitoyl phosphatidylcholine
- E.
Ganglioside
Correct Answer
D. Dipalmitoyl phosphatidylcholineExplanation
Respiratory Distress Syndrome ***Prevalent in premature infants
Due to a deficiency in synthesis of lung surfactant
The major constituents of surfactant are **dipalmitoylphosphatidylcholine**, phosphatidylglycerol, apoproteins (surfactant proteins:Sp A,B,C) and cholesterol
(slide 15 Memb Lip-Laville)Rate this question:
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- 20.
The site of action of the nonsteroidal anti-inflammatory drugs is:
- A.
Thromboxane synthase
- B.
Prostaglandin E dehydrogenase
- C.
Lipoxygenase
- D.
Cyclooxygenase
- E.
Prostacyclin synthase
Correct Answer
D. CyclooxygenaseExplanation
think COXRate this question:
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- 21.
Which of the following phospholipids induces hypersensitivity, triggers thrombotic events and causes alveolar macrophages to generate superoxide radicals?
- A.
Cardiolipin
- B.
Phosphatidylinositol
- C.
Plasmalogens
- D.
Dipalmitoylphophatidylcholine
- E.
Platelet activating factor
Correct Answer
E. Platelet activating factorExplanation
Platelet activating factor (PAF)
Hormone released from phagocytic cells binds to surface receptors
Causes platelets to aggregate and degranulate. It binds to surface receptors resulting in thrombotic and inflammatory events and anaphylactic reactions
Causes neutrophils and alveoli macrophages to produce superoxide radicals (useful for killing bacteria) (slide 18 Memb Lip-Laville)Rate this question:
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- 22.
Cytidine nucleotides are involved in phospholipid synthesis because:
- A.
They are involved in the activation of choline, ethanolamine and diacylglycerol (DAG)
- B.
They provide the energy to convert choline to ethanolamine
- C.
They are involved in the phosphorylation of choline and ethanolamine
- D.
They are recognition molecules for phospholipid transferases
- E.
They are important in signal transduction
Correct Answer
A. They are involved in the activation of choline, ethanolamine and diacylglycerol (DAG)Explanation
Cytidine nucleotides are involved in phospholipid synthesis because they play a role in the activation of choline, ethanolamine, and diacylglycerol (DAG). These molecules are important components in the synthesis of phospholipids, which are essential for building cell membranes. By activating choline, ethanolamine, and DAG, cytidine nucleotides contribute to the production of phospholipids, ensuring the proper structure and function of cell membranes.Rate this question:
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- 23.
Lipoprotein lipase is a very important enzyme in lipid metabolism. Found on many tissues in the body its main function is to facilitate the fatty acid uptake in these tissues. In a patient with severely decreased insulin output after a meal, what would you expect to be the metabolic outcome?
- A.
The patient can go into cardiac arrest because of lack of fatty acids for ATP production.
- B.
A plasma sample taken 45 minutes after a meal would reveal high levels of triglycerides due to lack of function of adipose tissue lipoprotein lipase
- C.
Coma could result because of lack of fatty acids as fuel for the brain
- D.
The patient would present with low levels of plasma ketone bodies due to lack of uptake of fatty acids in liver
- E.
A plasma sample would reveal both low levels of triglycerides and glucose
Correct Answer
B. A plasma sample taken 45 minutes after a meal would reveal high levels of triglycerides due to lack of function of adipose tissue lipoprotein lipaseExplanation
Lipoprotein lipase is responsible for facilitating the uptake of fatty acids in tissues, including adipose tissue. When there is severely decreased insulin output after a meal, the function of adipose tissue lipoprotein lipase is impaired. As a result, there is a lack of fatty acid uptake in adipose tissue, leading to high levels of triglycerides in the plasma. This occurs because the fatty acids are not being properly utilized and stored in adipose tissue, causing them to remain in the bloodstream.Rate this question:
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- 24.
A patient reports to you that he has had aches and pains in his muscles for the past seven days. A blood test shows increased levels of creatine kinase MM, fatty acids and also myoglobin. A second blood sample, this time taken after an overnight fast, revealed low levels of blood glucose and elevated very low density lipoprotein (VLDL). This patient most likely has which of the following conditions?
- A.
Essential amino acid deficiency
- B.
Type 1 glycogen storage disease
- C.
Acute alcohol toxicity
- D.
Carnitine acyltranferase deficiency
- E.
Elevated insulin levels, which cause the hypoglycemia and increase fatty acid mobilization from adipose tissue
Correct Answer
D. Carnitine acyltranferase deficiencyExplanation
Diseases of carnitine shuttle
Systemic primary carnitine deficiency: SLC22A5 gene on chromosome 5q31.1, renal re-uptake transporter OCTN2 (Na+-cotransport). Frequency Faroe Islands 1 in every 500, otherwise 1 in several 10000. OMIM #212140.
Hypoketotic hypoglycemia, Reye-syndrom like episodes, lethargy, somnolence, hepato- and cardiomegaly.
Treatment: oral supplementation of carnitine
Carnitine palmitoyltransferase I deficiency: hypoketotic hypoglycemia, Reye-syndrom like episodes,
hepatomegaly, muscle weakness. OMIM #255120.
Treatment: prevent hypoglycemia with short- and medium-chain fa in diet
Carnitine-acylcarnitine translocase deficiency: Presents within hours of birth with seizures, bradycardia, breathing problems, hypoketotic hypoglycemia, hyperammonemia, hepatomegaly, cardiomyopathy, muscle weakness, sudden infant death. OMIM #212138.
Treatment: low lipid intake, medium chain fa, carnitine, avoid strenuous exercise.
Carnitine palmitoyltransferase II deficiency: Three forms:
Adult: OMIM #255110. Muscle problems (myalgia, rhabdomyolysis, myoglobinuria) during attacks, otherwise normal. Attacks induced by exercise, fasting, high-fat diet, infection. Highly variable age of onset, | more strongly affected.
Infantile: OMIM #600649. Age of onset usually _ 1a, but sometimes later. Hypoketotic hypoglycemia, loss of consciousness and seizures, hepato- and cardiomegaly.
Neonate: OMIM #608836. Onset hours to days after birth, rapidly fatal from cardiac, respiratory or liver failure.
Neuronal migration defects, kidney dysorganization. carnitine formed in liver and kidney from Lys and Met
supplementation not required in healthy individual 12 C-atoms pass membrane by diffusion
distribution of acyl-CoA between cytosol (anabolic) and mito (catabolic)
rate-limiting step of FA breakdown!
( slide 20-22 F.A metab-BUX)Rate this question:
-
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