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Regulation and Pathology of Lipid Metabolism
The Department of Biochemistry of Medical Faculty Presents now Regulation and Pathology of Lipid Metabolism Edited by Attila Sandor
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Regulation and Pathology of Lipid Metabolism
The fatty acid-glucose cycle Regulation of cholesterol synthesis at HMG-CoA reductase the inhibitory effect of cholesterol by covalent modification (-P) at the level of gene expression Regulation of ketogenesis at HMG-CoA synthase by succinylation changed gene expression Regulation of fatty acid synthesis at acetyl-CoA carboxylase Pathological lipid metabolism Tay-Sachs disease Propionemia, methylmalonemia Familial hypercholesterolemia Author`s picture
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Combined inhibititory effect of ATP and citrate on the PFK activity
Reg. in Metab. by Newsholm, 1977
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Author`s picture
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The theory of glucose/fatty acid cycle
The theory of the cycle states, if plasma Glc is decreased, fatty acids are mobilized from adipose tissues (fasting, effect of glucagon) and the increased fatty acid level will decrease Glc utilization, restoring Glc level and maintaining homeostasis in this way. Author`s picture
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Regulation and Pathology of Lipid Metabolism
The fatty acid-glucose cycle Regulation of cholesterol synthesis at HMG-CoA reductase the inhibitory effect of cholesterol by covalent modification (-P) at the level of gene expression Regulation of ketogenesis at HMG-CoA synthase by succinylation changed gene expression Regulation of fatty acid synthesis at acetyl-CoA carboxylase Pathological lipid metabolism Tay-Sachs disease Propionemia, methylmalonemia Familial hypercholesterolemia Author`s picture
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HMG-CoA is a branchpoint
Cholesterol Reductase HMG-CoA synthase Cleavage enzyme Ketone bodies
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HMG-CoA reductase is the regulated enzyme
on the way to cholesterol synthesis HMG-CoA Phosphorylation by AMPK Cholesterol Insulin Gene Expression Glucagon Drugs (Statins)
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AMP dependent Protein Kinase
Authors`picture
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Regulation and Pathology of Lipid Metabolism
The fatty acid-glucose cycle Regulation of cholesterol synthesis at HMG-CoA reductase the inhibitory effect of cholesterol by covalent modification (-P) at the level of gene expression Regulation of ketogenesis at HMG-CoA synthase by succinylation changed gene expression Regulation of fatty acid synthesis at acetyl-CoA carboxylase Pathological lipid metabolism Tay-Sachs disease Propionemia, methylmalonemia Familial hypercholesterolemia Author`s picture
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HMG-CoA synthase is regulatorory for
ketone body synthesis
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Regulation of ketone body synthesis trough the HMG-CoA synthase
Acetoacetyl-CoA Acetyl-CoA HMG-CoA synthase Acetyl-CoA Succinyl-CoA HMG-CoA The liver contains two HMG-CoA synthases, one cytosolic for cholesterol synthesis and an other mitochondrial rate limiting for for ketone body synthesis. The latter undergoes a short term covalent modification via succinylation/desuccinylation of pre-existing enzyme. This presents a rare way of covalent modification of an enzyme.
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Regulation and Pathology of Lipid Metabolism
The fatty acid-glucose cycle Regulation of cholesterol synthesis at HMG-CoA reductase the inhibitory effect of cholesterol by covalent modification (-P) at the level of gene expression Regulation of ketogenesis at HMG-CoA synthase by succinylation changed gene expression Regulation of fatty acid synthesis at acetyl-CoA carboxylase Pathological lipid metabolism Tay-Sachs disease Propionemia, methylmalonemia Familial hypercholesterolemia Author`s picture
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Regulation of acetyl-CoA carboxylase (ACC)
CH3-COSCoA COO-CH3-COSCoA ACC CO2-Biotin acetyl-CoA malonyl-CoA Glucagon Insulin ACC, the 2nd and ATP-citrate lyase, the1st lipogenic enzymes are regulated by an inhibiting phosphorylation Stryer,5th ed , p.625
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Regulation and Pathology of Lipid Metabolism
The fatty acid-glucose cycle Regulation of cholesterol synthesis at HMG-CoA reductase the inhibitory effect of cholesterol by covalent modification (-P) at the level of gene expression Regulation of ketogenesis at HMG-CoA synthase by succinylation changed gene expression Regulation of fatty acid synthesis at acetyl-CoA carboxylase Pathological lipid metabolism Tay-Sachs disease Propionemia, methylmalonemia Familial hypercholesterolemia Author`s picture
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Genetic diseasis in connection to fatty acid oxidation
propionemia methylmalonyl-uria member of citric acid cycle Lehn.,4th ed p.642
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Regulation and Pathology of Lipid Metabolism
The fatty acid-glucose cycle Regulation of cholesterol synthesis at HMG-CoA reductase the inhibitory effect of cholesterol by covalent modification (-P) at the level of gene expression Regulation of ketogenesis at HMG-CoA synthase by succinylation changed gene expression Regulation of fatty acid synthesis at acetyl-CoA carboxylase Pathological lipid metabolism Tay-Sachs disease Propionemia, methylmalonemia Familial hypercholesterolemia Author`s picture
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THANK YOU FOR YOUR ATTENTION
The honored audience has the opportunity now to download the pictures of this lecture from here or from the intranet: RegPathLipidMetab.ppt Attila Sandor
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