1pp Omega_3_fatty_acids

1pp Omega_3_fatty_acids - OmegaOmega-3 Fatty Acids in...

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Unformatted text preview: OmegaOmega-3 Fatty Acids in Health Essential Fatty Acids Essential Fatty Acids Certain unsaturated fatty acids are essential Certain unsaturated fatty acids are essential Humans Humans lack specific enzymes for synthesis – Unable to make a double bond before C9 Omega carbon Methyl end Carbon 9 Acid end end Omega Omega 3-6-9 Fatty Acids Fatty Acids 1st double bond: 3rd C from methyl end bond: from methyl end – Linolenic, Eicosapentanoic, Docosahexanoic Eicosapentanoic, 1st double bond: 6th C from methyl end – Linoleic, Arachidonic 1st double bond: 9th C from methyl end – Oleic ~ NOT essential Fatty Acid Length Fatty Acid Length Linolenic Linolenic acid (omega 3) (omega 3) Linolenic Linolenic used to make Ei Eicosapentanoic acid (EPA) (EPA) EPA EPA used to make Docosahexanoic acid (DHA) Linoleic Linoleic acid (omega 6) Linoleic sed to make Arachidonic Linoleic used to make Arachidonic acid Fatty Acid Length Fatty Acid Length Shorter chain EFA can be: Shorter chain EFA can be: – Lengthen at acid end Two carbons at time Two carbons at a time – Desaturated (dehydrogenation) Add double bond Add a double bond – May not be efficient in humans Acid end Methyl end Fatty Acid Sources Fatt Essential Fatty Acid Function Essential Fatty Acid Function Structural role Structural role – Cell membrane components Essential Fatty Acid Function Essential Fatty Acid Function Physiological roles Physiological roles – Neural development – Fetal development – High concentrations in Brain synapses Retina Retina Essential Fatty Acid Function Essential Fatty Acid Function Regulatory Regulatory roles – Cell signaling and genetic control Immune Immune system Cardiovascular system Cardiovascular system Metabolism Metabolism Essential Fatty Acid Deficiency Essential Fatty Acid Deficiency Impaired brain/neural development Impaired brain/neural development Memory Memory disturbances Loss Loss of visual acuity Re Reproductive disturbances Immune Immune system? Cardiovascular system? Cardiovascular system? Metabolism? Metabolism? Essential Fatty Acid Function Essential Fatty Acid Function Immunological role Immunological role – Cell growth and maintenance – Metabolized to form immune cells – Derived from cell membrane phospholipids Immune System Immune System Innate immunity Innate immunity – Non-specific Non– First line of defense First line of defense – Barriers to prevent infection Immune System Immune System Acquired Acquired – Specific learned response – Infers resistance resistance vaccination vaccination – T cells/B cells antibodies antibodies cytokines cytokines Controlled by fatty acid derived compounds: Eicosanoids Eicosanoids Eicosanoids Hormone like substances Hormone-like substances – Prostaglandins, Leukotrienes, Thromboxanes Leukotrienes, Produced from cell membrane phospholipid – Omega-6 / Omega-3 fatty acid tail Omega- Omega- Mediate Mediate a wide range of physiological functions – Trigger cytokine release – Modulation of inflammation Cytokines Cytokines Chemical messengers Chemical messengers – Regulate cellular activity Signal Signal cell division and differentiation – Increase cell number in inflammation High High levels of cytokines are destructive – Increase inflammation Increase inflammation – Muscle wasting, bone mass loss Omega or Omega Omega-6 or Omega-3 Cellular concentration reflects diet Cellular concentration reflects diet – α-linolenic acid and linoleic acid compete in elongation – Eicosapentanoic acid (omega-3) or arachidonic acid (omega 3) or arachidonic acid (omega(omega-6) can be used interchangeably Physiological responses to EPA/AA products differ Physiological responses to EPA/AA products differ EPA EPA Eicosanoids You are what you eat Leukotriene 4 Prostaglandin E2 Prostaglandin E2 Leukotriene 5 Prostaglandin E3 E3 Eicosanoids Arachidonic Acid Eicosapentanoic acid Omega to Omega Ratios Omega-6 to Omega-3 Ratios Western diet: 10:1 to 20:1 Western diet: 10:1 to 20:1 Ancestral diet: 1 to 2:1 Greenland Greenland Eskimos: 4:1 Greenland Eskimos Greenland Eskimos High dietary omega-3 fatty acids from fish High dietary omega fatty acids from fish Low Low rate of autoimmune and inflammatory di disorders compared to westernized ethnic counterparts Simopoulos (2002) Potential Potential Benefits: Preliminary Research EvidenceEvidence-Many Studies Ongoing Inflammatory/Autoimmune diseases Inflammatory/Autoimmune diseases Cardiovascular Cardiovascular disease Metabolic Metabolic Syndromes Pregnancy Cancer Cance ?? ?? Potential Potential But Not Proven Benefits Benefits - Inflammation Rheumatoid Arthritis Rheumatoid Arthritis – Reduced inflammatory response – Reduce pain and stiffness – Reduce NSAID use (non(non-steroidal antiinflammatory drug) Surgery Surgery complications – Anti-inflammatory – Reduce sepsis – Reduced hospital stay Reduced hospital stay Inflammation Inflammation Normal response to injury Normal response to injury – Increased blood flow and capillary permeability – Immune cells concentrate at the site of infection th Inflammation Inflammation Undesirable Undesirable response when chronic or in excess excess – Rheumatoid arthritis – Gastrointestinal diseases di – Cardiovascular disease – Post-surgery Post- Immunomodulation Immunomodulation Alternate forms of immune Alternate forms of immune messengers messengers – Differential physiological Diff effects effects Regulation Regulation of genes coding for immune components – Differential cell signaling Cytokine release Leukotriene 4 Prostaglandin E2 E2 Leukotriene 5 Prostaglandin E3 l E3 Eicosanoids Arachidonic Acid Acid Eicosapentanoic acid acid Genetic Control Genetic Control Direct interaction Direct interaction – Genes found with PUFA sensitive regions Reduced Reduced transcription of immune components – Enzymes – Cytokines Supports Supports effects of altered membrane composition Potential Potential Not Proven Benefits Omega 3 Fatty Acids - Cardiovascular Fatty Cardiovascular disease and stroke Cardiovascular disease and stroke – Anti-inflammatory Anti– Anti-arrhythmic – Anti-thrombotic Anti– Reduces restenosis Reduces restenosis – Reduces plaque formation – Reduces blood triacylglycerol Reduces blood triacylglycerol Related Related Potential Beneficial Effects: Effects: Omega 3 Fatty Acids Anti arrhythmic Anti-arrhythmic – Alter ion currents within the myocardium – Reduces risk of fatal rhythm irregularities Improve endothelial function Im – Enhance Nitric oxide production – Reduce vasoconstriction vasoconstriction Potential Potential Benefits Omega 3 Fatty Fatty Acids - Metabolic Metabolic Syndrome diabetes obesity Metabolic Syndrome, diabetes, obesity – Increase glucose uptake – Improves lipid profile Improves lipid profile – Favors fatty acid oxidation – Aids in weight loss Energy Energy Balance: PUFA vs Monounsaturated Polyunsaturated fatty acids instead of Polyunsaturated fatty acids instead of monounsaturated monounsaturated influence metabolism – Favor fatty acid oxidation over storage fatty acid oxidation over storage Alter Alter gene transcription – Reduced adipose stores – Reduced fatty liver Decreased plasma triglycerides Decreased Increase Increase insulin sensitivity – Increase glucose transport Genetic Genetic Control by Polyunsaturated Polyunsaturated Fatty Acids Suppression of fat storage and synthesis Suppression of fat storage and synthesis – Acetyl-CoA carboxylase Acetyl– Fatty acid synthase Fatty acid synthase Induction Induction of fatty acid oxidation – Carnitine palmitoyltransferase – Fatty acyl-CoA synthase acyl- Induction Induction of thermogenesis Essential Essential Fatty Acids: Pregnancy Pregnancy Essential for healthy fetal development Essential for healthy fetal development Slightly Slightly longer pregnancy – Lower risk of pre-term birth pre– Lower risk of preeclampsia – Reduced disease risk for offspring in in later life Cardiovascular Cardiovascular disease Diabetes Diabetes Summary Summary Omega PUFA act though both specific Omega-3 PUFA act though both specific and and combined mechanisms May be useful in treating and preventing disease conditions Increasing Increasing omega 3:6 ratio is key Recommended intake Recommended intake Cardiovascular Cardiovascular disease disease – 1-4 g/day in studies g/day in studies Average Average US intake – 0.1-0.5 g/day 0.1-0.5 EPA+DHA Recommendation Recommendation by American Heart Association – 1.3-2.7 g/day EPA+DHA Fish Fish intake intake Monthly Risk Risk reduction reduction ~20% Weekly Weekly ~30% Several times per week ~34% Recommended intake Recommended intake General Recommendations General Recommendations – Increase fish intake – Supplements may be required for effective dose – Reduce omega-6 : omega-3 ratio omega- omega- Potential Risks: Fatty Fish Intake Potential Risks: Fatty Fish Intake Presence Presence of carcinogenic and toxic substances – DDT, PCB, Methyl mercury Present in low levels in lakes rivers ocean Present in low levels in lakes, rivers, ocean Higher Higher concentrations are in fat and skin Hi Higher risk for children and pregnant women Potential Risks: Supplements Potential Risks: Supplements Supplemental fish oil may be safer due to Supplemental fish oil may be safer due to purification purification processes – Pharmaceutical grade Ph – Free of all heavy metals and contaminants ...
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This note was uploaded on 12/09/2011 for the course HUN 4445 taught by Professor Sitren during the Spring '08 term at University of Florida.

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