Lipid Chemistry and Metabolism

  1. Fatty Acid Catabolism
    1. Mobilization of Stored Triacylglycerols
      1. Hormonal Control of Lipolysis
        1. Stimulatory Hormones
          1. Glucagon
            1. Epinephrine
              1. Growth Hormone
                1. Cortisol
                2. Inhibitory Hormones
                  1. Insulin
                3. Hormone-Sensitive Lipase (HSL)
                  1. Structure and Regulation
                    1. Phosphorylation Control
                      1. Substrate Specificity
                      2. Adipose Triglyceride Lipase (ATGL)
                        1. Role in Initial Hydrolysis
                          1. Regulation
                          2. Monoacylglycerol Lipase
                            1. Final Hydrolysis Step
                            2. Release into Circulation
                              1. Free Fatty Acid Transport
                                1. Albumin Binding
                                  1. Glycerol Transport
                                2. Fatty Acid Activation and Mitochondrial Entry
                                  1. Activation to Fatty Acyl-CoA
                                    1. Acyl-CoA Synthetase Reaction
                                      1. ATP Requirement
                                        1. Subcellular Localization
                                        2. Carnitine Shuttle System
                                          1. Carnitine Palmitoyltransferase I (CPT-I)
                                            1. Rate-Limiting Step
                                              1. Malonyl-CoA Inhibition
                                                1. Tissue-Specific Isoforms
                                                2. Carnitine-Acylcarnitine Translocase
                                                  1. Antiport Mechanism
                                                    1. Inner Membrane Location
                                                    2. Carnitine Palmitoyltransferase II (CPT-II)
                                                      1. Matrix-Side Enzyme
                                                        1. Regeneration of Acyl-CoA
                                                    3. Beta-Oxidation Pathway
                                                      1. Mitochondrial Beta-Oxidation
                                                        1. Cycle of Four Reactions
                                                          1. Acyl-CoA Dehydrogenase (FAD-linked)
                                                            1. Enoyl-CoA Hydratase
                                                              1. 3-Hydroxyacyl-CoA Dehydrogenase (NAD+-linked)
                                                                1. Thiolase (Acetyl-CoA Acetyltransferase)
                                                                2. Products per Cycle
                                                                  1. Acetyl-CoA
                                                                    1. NADH
                                                                      1. FADH2
                                                                      2. Energy Yield Calculations
                                                                        1. ATP from Acetyl-CoA Oxidation
                                                                          1. ATP from NADH and FADH2
                                                                            1. Net ATP Yield
                                                                          2. Oxidation of Unsaturated Fatty Acids
                                                                            1. Monounsaturated Fatty Acids
                                                                              1. Enoyl-CoA Isomerase Requirement
                                                                                1. Pathway Modifications
                                                                                2. Polyunsaturated Fatty Acids
                                                                                  1. Additional Enzyme Requirements
                                                                                    1. 2,4-Dienoyl-CoA Reductase
                                                                                      1. Complex Pathway Modifications
                                                                                    2. Oxidation of Odd-Chain Fatty Acids
                                                                                      1. Formation of Propionyl-CoA
                                                                                        1. Propionyl-CoA Carboxylase
                                                                                          1. Methylmalonyl-CoA Mutase
                                                                                            1. Conversion to Succinyl-CoA
                                                                                              1. Vitamin B12 Requirement
                                                                                            2. Peroxisomal Beta-Oxidation
                                                                                              1. Substrate Specificity
                                                                                                1. Very-Long-Chain Fatty Acids
                                                                                                  1. Branched-Chain Fatty Acids
                                                                                                    1. Dicarboxylic Acids
                                                                                                    2. Enzymatic Differences
                                                                                                      1. Acyl-CoA Oxidase
                                                                                                        1. H2O2 Production
                                                                                                          1. Catalase Function
                                                                                                          2. Physiological Significance
                                                                                                            1. Chain Shortening
                                                                                                              1. Specialized Fatty Acid Metabolism
                                                                                                            2. Ketogenesis
                                                                                                              1. Conditions Favoring Ketogenesis
                                                                                                                1. Prolonged Fasting
                                                                                                                  1. Starvation
                                                                                                                    1. Low-Carbohydrate Diets
                                                                                                                      1. Uncontrolled Diabetes Mellitus
                                                                                                                        1. High-Fat Diets
                                                                                                                        2. Hepatic Ketone Body Synthesis
                                                                                                                          1. Mitochondrial Location
                                                                                                                            1. Substrate Availability
                                                                                                                              1. Enzymatic Pathway
                                                                                                                                1. Thiolase
                                                                                                                                  1. HMG-CoA Synthase
                                                                                                                                    1. HMG-CoA Lyase
                                                                                                                                  2. Types of Ketone Bodies
                                                                                                                                    1. Acetoacetate
                                                                                                                                      1. Primary Ketone Body
                                                                                                                                        1. Chemical Properties
                                                                                                                                        2. 3-Hydroxybutyrate (Beta-hydroxybutyrate)
                                                                                                                                          1. Reduced Form
                                                                                                                                            1. Predominant in Blood
                                                                                                                                            2. Acetone
                                                                                                                                              1. Spontaneous Decarboxylation Product
                                                                                                                                                1. Volatile and Excreted
                                                                                                                                              2. Ketone Body Utilization
                                                                                                                                                1. Extrahepatic Tissues
                                                                                                                                                  1. Brain Adaptation
                                                                                                                                                    1. Muscle Utilization
                                                                                                                                                      1. Heart Preference
                                                                                                                                                      2. Enzymatic Activation
                                                                                                                                                        1. Succinyl-CoA:3-Ketoacid CoA Transferase
                                                                                                                                                          1. Acetoacetyl-CoA Thiolase
                                                                                                                                                        2. Regulation of Ketogenesis
                                                                                                                                                          1. Substrate Availability
                                                                                                                                                            1. Hormonal Control
                                                                                                                                                              1. Tissue-Specific Factors

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                                                                                                                                                          6. Lipid Digestion, Absorption, and Transport

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                                                                                                                                                          8. Fatty Acid Anabolism