טבעוני ובריא- האם זה אפשרי? למי ומדוע?
מצגת מקורית של גיא בן צבי מאומגה 3 גליל המסבירה את המטבוליזם שמאפשר או שאינו מאפשר חיים אכילה טבעונית ושמירה על בריאות הגוף
הוצג בכנס שותפים לדרך של אומגה 3 גליל
שכניה
מרץ 2014
7. המחקר אומר מה חיוניות שומן חומצות המרת?
Single nucleotide polymorphisms in the FADS gene cluster are associated with delta-5 and
delta-6 desaturase activities estimated by serum fatty acid ratios Szilvia Bokor et al, on behalf
of the HELENA Study Group
Abstract
Genetic variability in the FADS1-FADS2 gene cluster [encoding delta-5 (D5D) and delta-6 (D6D) desaturases]
has been associated with plasma long-chain PUFA (LCPUFA) and lipid levels in adults. To better understand
these relationships, we further characterized the association between FADS1-FADS2 genetic variability and
D5D and D6D activities in adolescents. Thirteen single nucleotide polymorphisms (SNPs) were genotyped in
1,144 European adolescents (mean ± SD age: 14.7 ± 1.4 y). Serum phospholipid fatty acid levels were analyzed
using gas chromatography. D5D and D6D activities were estimated from the C20:4n-6/C20:3n-6 and C20:3n-
6/C18:2n-6 ratios, respectively. Minor alleles of nine SNPs were associated with higher 18:2n-6 levels (1.9E-18
≤ P ≤ 6.1E-5), lower C20:4n-6 levels (7.1E-69 ≤ P ≤ 1.2E-12), and lower D5D activity (7.2E-44 ≤ P ≤ 4.4E-5). All
haplotypes carrying the rs174546 minor allele were associated with lower D5D activity, suggesting that this
SNP is in linkage disequilibrium with a functional SNP within FADS1. In contrast, only the rs968567 minor allele
was associated with higher D6D activity (P = 1.5E-6). This finding agrees with an earlier in vitro study showing
that the minor allele of rs968567 is associated with a higher FADS2 promoter activity. These results suggest
that rare alleles of several SNPs in the FADS gene cluster are associated with higher D6D activity and lower
D5D activity in European adolescents.
משמעות:
בין גנטיים הבדלים13
קובעים שונים וריאנטיים
של ההמרה יעילות את
אומגה3ל צמחיתEPA
ושלEPAלDHA
אחרות במיליםניתן לא
ממיר מי מראש לדעת
לא ומי טוב
גנים ב גנטיים וריאנטיםFADS1,2אנזימי בעזרת ההמרה יעילות את קובעיםD5DוD6D
ובריא טבעוני?
8. המחקר אומר מה חיוניות שומן חומצות?
משמעות:
בין גנטיים הבדלים4וריאנטיים
ההמרה יעילות את קובעים שונים
אומגה של3ל צמחיתEPA.
מעטים אנשים(הומוזיגוטים
רצסיביים)משמעותית תועלת יראו
אומגה בצריכת3צמחית(במחקר
לב מחלות בפני להגנה הכוונה זה)
לדעת ניתן לא אחרות במילים
לא ומי טוב ממיר מי מראש
Dietary oils and FADS1-FADS2 genetic variants modulate [13C]a-
linolenic acid metabolism and plasma fatty acid composition. Leah G
Gillingham, et al. The American Journal of Clinical Nutrition Jan 11
2013
DISCUSSION
Our first main finding was that a high dietary intake of ALA (10% of energy) decreased
the apparent conversion of [U-13C]ALA to EPA and DPA compared with a typical WD.
Second, minor allele variants in FADS1-FADS2 showed decreased desaturase
activity as measured by lower plasma [13C]EPA and percentage composition of
EPA. However, increasing ALA intake in minor allele homozygotes resulted in an
increased plasma composition of EPA beyond that of major allele homozygotes
consuming a typical WD. Finally, our study also substantiates that dietary ALA and
common FADS genetic variants fail to modulate the plasma composition of DHA in
humans.
גנים ב גנטיים וריאנטיםFADS1,2של ההמרה יעילות את קובעיםALAלEPA
ובריא טבעוני?
9. המחקר אומר מה חיוניות שומן חומצות המרת?
משמעות:
וטסטוסטרון אבץ מגנזיום
חיוניים קואנזימים הינם
האנזימים לפעולתD6Dו
D5Dהמרת על האחראים
אומגה3שמן ל צמחית
בגוף דגים.
אחרות במילים אומחסור
או אבץ או במגנזיום
המרה ימנעו טסטוסטרון
אומגה של יעילה3צמחית
בגוף דגים לשמן
CHANGES OF LINOLEIC ACID METABOLISM AND
CELLULAR PHOSPHOLIPID FATTY ACID
COMPOSITION IN LLC-PK CELLS CULTURED AT LOW
MAGNESIUM CONCENTRATIONS
Mahfouz MM, Smith TL, Kummerow FA.
Biochim Biophys Acta, 1989 Nov 6;1006(1):70-4.
LLC-PK cells grown on media containing normal (480
microM) or reduced magnesium levels (25, 6.3 or 2.5
microM) were used to study the effect of
magnesium deficiency on linoleic acid metabolism
and cellular membrane fatty acids. The fatty acid
composition of the cellular phospholipids showed a
significant decrease in 20:4(n-6) and 22:4(n-6) acids
and a significant increase in 18:2(n-6), 18:3(n-6) and
20:3(n-6) fatty acids in magnesium-deficient cells
compared to magnesium-sufficient cells. When [1-
14C] linoleic acid was incubated with control (480
microM Mg2+) or magnesium deficient cells (2.6
microM Mg2+) the rate of tetraenoic acid synthesis
(20:4(n-6) + 22:4(n-6) was significantly reduced in
magnesium-deficient cells, indicating that the
metabolic conversion of 18:2(n-6) to 20:4(n-6) is
impaired in magnesium deficiency. This reduction in
conversion may be due to the impairment of either
the delta5- or the delta6-desaturase, or both. This
study shows that magnesium deficiency perturbs
essential fatty acid (EFA) metabolism and decreases
the cellular membrane polyunsaturated fatty acid
(PUFA) content. These alterations are likely to have
adverse effects on cellular membrane properties
and functions.
EFFECTS OF ZINC DEFICIENCY AND CASTRATION ON FATTY
ACID COMPOSITION AND DESATURATION IN RATS
Clejan S, Castro-Magana M, Collipp PJ, Jonas E, Maddaiah VT.
Lipids, 1982 Mar;17(3):129-35.
The effects of zinc deficiency and testosterone on fatty acid
composition of plasma lipids and microsomes of liver, intestine
and testes were studied. The activities of fatty acid desaturase
(delta6 and delta5) in rat liver and testes were also measured.
A significant decrease in the level of arachidonic acid was
observed in plasma of normal rats fed the zinc-deficient diet.
Castration significantly decreased arachidonic acid but
increased 20:3 fatty acid, which is negligible in normal rats.
Testosterone and zinc administration restored arachidonic acid
to normal values. Zinc deficiency does not significantly change
the fatty acid profile in liver, but castration decreased both
arachidonic and 22:6 fatty acid. Intestinal mucosal microsomes
showed that the predominant fatty acid in this tissue, palmitic
acid, is independent of zinc status, whereas polyunsaturated
fatty acids 18:2 and 20:4 were decreased by zinc-deficient diet
or castration. Zinc deficiency sharply decreased 22:5 fatty acid
and to some extent, other polyunsaturated fatty acids in testis
microsome. These changes in fatty acids are in agreement with
increased delta9 desaturation and decreased delta5 desaturase
activity. In testes, both delta6 and delta5 desaturase activities
are decreased in zinc deficiency. It appears that zinc influences
the conversion of linoleic to arachidonic aid, whereas
testosterone influences delta6 desaturase activity. The data
suggest that zinc deficiency may be one of the important
factors in the causation of polyunsaturated fatty acid
deficiency, which, in turn, may induce serum
hypertriglyceridemia.
של ההמרה ויעילות מגנזיוםLAלAA(אומגה6) האנזימים ויעילות וטסטוסטרון אבץD5DD6D
ובריא טבעוני?