Guest guest Posted May 7, 2003 Report Share Posted May 7, 2003 Can someone clarify this for me If CF people are low on linolenic acid why do we supplment with DHA?? Is it ok to supplment with fish oils or are they competing for receptor sites in the body?? mum to Liam 8 months and better from his tummy bug Quote Link to comment Share on other sites More sharing options...
Guest guest Posted May 7, 2003 Report Share Posted May 7, 2003 Fish oils contain DHA and EPA. DHA reduces inflammation and (my understanding is) EPA is converted to arachidonic acid (AA), which increases inflammation. DHA derived from marine algae is available as a supplement and contains no EPA. Because increased inflammation is a big problem in cf, and because people with cf have been shown to be deficient in dha, supplements of algae-source dha is supposed to be helpful in decreasing inflammation and increasing the dha level in the body's tissues. When given DHA, cf mice had a reversal of symptoms. Unfortunately, people aren't as easily treated as mice. See the abstracts below from Pub Med. ~ > Can someone clarify this for me > If CF people are low on linolenic acid why do we supplment with DHA?? > Is it ok to supplment with fish oils or are they competing for receptor sites in the body?? > > mum to Liam 8 months and better from his tummy bug : Curr Opin Pulm Med 2000 Nov;6(6):530-2 Related Articles, Links Fatty acids in cystic fibrosis. Freedman SD, Shea JC, Blanco PG, Alvarez JG. Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA. sfreedma@... Cystic fibrosis (CF) is associated with deficiencies in certain essential fatty acids. These deficiencies have been studied in plasma, red blood cells, and mucus and were previously thought to be a result of malnutrition or malabsorption. More recent studies have indicated that these deficiencies are independent of nutritional status. However, these studies examined fatty acids in plasma but not in CF-regulated tissues. In the pancreas, lungs, and ileum of CF knock-out mice, membrane-bound arachidonic acid levels have been shown to be increased while docosahexaenoic acid levels are decreased. This lipid abnormality is reversed following oral administration of docosahexaenoic acid (DHA). In addition, DHA therapy reverses the increased neutrophil infiltration in the lungs of CF knock-out mice. Further studies are required to determine the mechanism by which CF gene mutations lead to this lipid abnormality. Publication Types: Review Review, Tutorial PMID: 11100964 [PubMed - indexed for MEDLINE] ---------------------------------- 1: Pharmacol Res 1999 Sep;40(3):211-25 Related Articles, Links Comment in: Pharmacol Res. 1999 Sep;40(3):203. Pharmacol Res. 1999 Sep;40(3):205-6. Health benefits of docosahexaenoic acid (DHA) Horrocks LA, Yeo YK. Docosa Foods Ltd, 1275 Kinnear Road, Columbus, OH 43212-1155, USA, Docosahexaenoic acid (DHA) is essential for the growth and functional development of the brain in infants. DHA is also required for maintenance of normal brain function in adults. The inclusion of plentiful DHA in the diet improves learning ability, whereas deficiencies of DHA are associated with deficits in learning. DHA is taken up by the brain in preference to other fatty acids. The turnover of DHA in the brain is very fast, more so than is generally realized. The visual acuity of healthy, full-term, formula-fed infants is increased when their formula includes DHA. During the last 50 years, many infants have been fed formula diets lacking DHA and other omega-3 fatty acids. DHA deficiencies are associated with foetal alcohol syndrome, attention deficit hyperactivity disorder, cystic fibrosis, phenylketonuria, unipolar depression, aggressive hostility, and adrenoleukodystrophy. Decreases in DHA in the brain are associated with cognitive decline during aging and with onset of sporadic Alzheimer disease. The leading cause of death in western nations is cardiovascular disease. Epidemiological studies have shown a strong correlation between fish consumption and reduction in sudden death from myocardial infarction. The reduction is approximately 50% with 200 mg day(-1)of DHA from fish. DHA is the active component in fish. Not only does fish oil reduce triglycerides in the blood and decrease thrombosis, but it also prevents cardiac arrhythmias. The association of DHA deficiency with depression is the reason for the robust positive correlation between depression and myocardial infarction. Patients with cardiovascular disease or Type II diabetes are often advised to adopt a low-fat diet with a high proportion of carbohydrate. A study with women shows that this type of diet increases plasma triglycerides and the severity of Type II diabetes and coronary heart disease. DHA is present in fatty fish (salmon, tuna, mackerel) and mother's milk. DHA is present at low levels in meat and eggs, but is not usually present in infant formulas. EPA, another long-chain n-3 fatty acid, is also present in fatty fish. The shorter chain n-3 fatty acid, alpha-linolenic acid, is not converted very well to DHA in man. These longchain n-3 fatty acids (also known as omega-3 fatty acids) are now becoming available in some foods, especially infant formula and eggs in Europe and Japan. Fish oil decreases the proliferation of tumour cells, whereas arachidonic acid, a longchain n-6 fatty acid, increases their proliferation. These opposite effects are also seen with inflammation, particularly with rheumatoid arthritis, and with asthma. DHA has a positive effect on diseases such as hypertension, arthritis, atherosclerosis, depression, adult-onset diabetes mellitus, myocardial infarction, thrombosis, and some cancers. Copyright 1999 Academic Press. Publication Types: Review Review, Tutorial PMID: 10479465 [PubMed - indexed for MEDLINE] ------------------ 1: Proc Natl Acad Sci U S A 1999 Nov 23;96(24):13995-4000 Related Articles, Links A membrane lipid imbalance plays a role in the phenotypic expression of cystic fibrosis in cftr(-/-) mice. Freedman SD, Katz MH, EM, Laposata M, Urman MY, Alvarez JG. Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA. A deficiency in essential fatty acid metabolism has been reported in plasma from patients with cystic fibrosis (CF). However, its etiology and role in the expression of disease is unknown. The objective of this study was to determine whether alterations in fatty acid metabolism are specific to CF-regulated organs and whether they play a role in the expression of disease. A membrane lipid imbalance was found in ileum, pancreas, and lung from cftr(-/-) mice characterized by an increase in phospholipid-bound arachidonic acid and a decrease in phospholipid-bound docosahexaenoic acid (DHA). This lipid imbalance was observed in organs pathologically affected by CF including lung, pancreas, and ileum and was not secondary to impaired intestinal absorption or hepatic biosynthesis of DHA. As proof of concept, oral administration of DHA to cftr(-/-) mice corrected this lipid imbalance and reversed the observed pathological manifestations. These results strongly suggest that certain phenotypic manifestations of CF may result from remediable alterations in phospholipid-bound arachidonic acid and DHA levels. PMID: 10570187 [PubMed - indexed for MEDLINE] ----------------------- : J Appl Physiol 2002 May;92(5):2169-76 Related Articles, Links Characterization of LPS-induced lung inflammation in cftr-/- mice and the effect of docosahexaenoic acid. Freedman SD, Weinstein D, Blanco PG, ez- P, Urman S, Zaman M, Morrow JD, Alvarez JG. Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA. sfreedma@... The mechanism by which Pseudomonas causes excessive inflammation in the cystic fibrosis lung is unclear. We have reported that arachidonic acid is increased and docosahexaenoic acid (DHA) decreased in lung, pancreas, and ileum from cftr-/- mice. Oral DHA corrected this defect and reversed the pathology. To determine which mediators regulate inflammation in lungs from cftr-/- mice and whether inhibition occurs with DHA, cftr-/- and wild-type (WT) mice were exposed to aerosolized Pseudomonas lipopolysaccharide (LPS). After 2 days of LPS, tumor necrosis factor-alpha (TNF-alpha), macrophage inflammatory protein-2, and KC levels in bronchoalveolar lavage fluid were increased in cftr-/- compared with WT mice and not suppressed by pretreatment with oral DHA. Neutrophil levels were not different between cftr-/- and WT mice. After 3 days of aerosolized LPS, neutrophil concentration, TNF-alpha, and the eicosanoids 6-keto- PGF1alpha, PGF2alpha, PGE2, and thromboxane B2 were all increased in bronchoalveolar lavage fluid from cftr-/- mice compared with WT controls. Oral DHA had no significant effect on TNF-alpha levels in cftr-/- mice. In contrast, neutrophils and eicosanoids were decreased in cftr-/- but not in WT mice treated with DHA, indicating that the effects of DHA on these inflammatory parameters may be related to correction of the membrane lipid defect. PMID: 11960971 [PubMed - indexed for MEDLINE] Quote Link to comment Share on other sites More sharing options...
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