Oméga-3:
faits - thérapeutique et posologie
Maladies
de peau: 1,88g ou 6,0g/jour EPA et DHA
Les journaux spécialisés ont consacré
aux oméga-3 les articles suivants. La liste de ces publications
a été établie en avril 2003 et n'aspire nullement
à l'exhaustivité. Source: MEDLINE.
Ces données servent de référence pour les
médecins et les thérapeutes, de sorte à déterminer
la dose thérapeutique dans le cadre des maladies de
peau; psoriasis et névrodermite.
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Human
milk polyunsaturated long-chain fatty acids and secretory immunoglobulin
A antibodies and early childhood allergy.
Duchén K: Department of Health and Environment, Linköping
University Hospital, Sweden; Casas R, Fagerås-Böttcher
M, Yu G, Björkstén B
Pediatr Allergy Immunol 2000 Feb 11:29-39
Abstract
The possible protective effect of breast milk against atopic manifestations
in infancy, i.e. atopic eczema and food allergy, has been controversial
for the last decades. Besides the methodological problems, differences
in the composition of human milk could explain these controversies.
The aim of this study was to investigate the composition of polyunsaturated
fatty acids (PUFA) and secretory immunoglobulin A (S-IgA) levels
to food proteins (ovalbumin and beta-lactoglobulin) and an inhalant
allergen (cat) in milk from mothers of allergic and non-allergic
children. Blood samples were obtained at birth and at 3
months from 120 children. Skin prick tests were performed
at 6, 12 and 18 months, and the development of atopic diseases
was assessed in the children. Breast milk samples were collected
from their mothers at birth and monthly during the lactation period.
Milk PUFA composition was measured by gas chromatography, and
enzyme-linked immunosorbent assay (ELISA) was used to measure
total S-IgA, anti-cat S-IgA, anti-ovalbumin S-IgA, and anti-beta-lactoglobulin
S-IgA. Allergic disease developed in 44/120 children (22/63 children
of allergic mothers and 22/57 children of non-allergic mothers).
Lower levels of eicosapentaenoic acid, C20:5 n-3 (EPA), docosapentaenoic
acid C22:5 n-3 (DPA), and docosatetraenoic acid C22:4 n-6 (DHA)
(p < 0.05 for all) were found in mature milk from mothers of
allergic as compared to milk from mothers of non-allergic children.
The total n-6:total n-3 and the arachidonic acid, C20:4 n-6
(AA):EPA ratios were significantly lower in transitional and mature
milk from mothers of allergic children, as compared to milk
from mothers of non-allergic children. The PUFA levels in serum
of allergic and non-allergic children were largely similar, except
for higher levels of C22:4 n-6 and C22:5 n-6 (p < 0.05 for
both) and a higher AA:EPA ratio in serum phospholipids in the
former group (p < 0.05). Changes in the levels of milk PUFA
were reflected in changes in PUFA serum phospholipids, particularly
for the n-6 PUFA. The AA: EPA ratio in maternal milk was related,
however, to the AA:EPA only in serum from non-allergic children,
while this was not the case in allergic children. The levels of
total S-IgA, anti-cat S-IgA, anti-ovalbumin S-IgA, and anti-beta-lactoglobulin
S-IgA in milk from mothers of allergic, as compared to non-allergic,
children were similar through the first 3 months of lactation.
Low levels of n-3 PUFA in human milk, and particularly a high
AA:EPA ratio in maternal milk and serum phospholipids in the infants,
were related to the development of symptoms of allergic disease
at 18 months of age. The milk PUFA composition influenced
the composition of PUFA in serum phospholipids of the children.
We also showed that the lower levels of colostral anti-ovalbumin
S-IgA and lower total S-IgA in mature milk from atopic mothers
did not influence the development of allergic disease in the children
up to 18 months of age. The findings indicate that low alpha-linolenic
acid, C18:3 n-3 (LNA) and n-3 long-chain polyunsaturated fatty
acids (LCP) 20-22 carbon chains, but not the levels of S-IgA antibodies
to allergens, are related to the development of atopy in children.
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Atopic
sensitization during the first year of life in relation to long
chain polyunsaturated fatty acid levels in human milk.
Duchén K: Department of Paediatrics,
Linköping University, Sweden; Yu G, Björkstén B
Pediatr Res 1998 Oct 44:478-84
Abstract
The levels of the long chain polyunsaturated n-6 and
n-3 fatty acids (PUFA) were studied in colostrum and mature milk
of 29 atopic and 29 nonatopic mothers and related to sensitization
in their babies during the first 12 mo of life. The levels of
alpha-linolenic acid (LNA) were lower (0.96 versus 1.23 weight
percentage, p < 0.01) and the levels of dihomo-gamma-linoleic
acid were higher (0.36 versus 0.31 weight percentage, p < 0.05)
in mature milk from mothers of atopic babies (n = 24) compared
with mothers of nonatopic babies (n = 34). The total n-3 levels
and the ratio of n-6 PUFA/n-3 PUFA were similar in colostrum of
all mothers and then decreased significantly in mature milk (p
< 0.001), particularly in milk given to atopic babies. The
levels of the n-6 fatty acids arachidonic acid, C22:4, and C22:5
n-6 correlated in milk samples from nonatopic mothers (r = 0.61-0.97,
p < 0.05 to p < 0.001) but were largely absent in colostrum
and mature milk from atopic mothers. In contrast, LNA and
eicosapentaenoic levels correlated in colostrum from the atopic
mothers (r = 0.61-0.88) regardless of atopic sensitization in
the infants, whereas LNA correlated to C20:4 n-3 in colostrum
from nonatopic mothers of nonatopic infants. Furthermore, the
levels of the n-3 fatty acid C20:4 n-3 correlated significantly
to all n-6 fatty acids, except linoleic acid (r = 0.64-0.79, all
p < 0.01) in mature milk from nonatopic mothers of nonsensitized
children. Low levels of LNA and total n-3 long chain polyunsaturated
fatty acids, in mature milk from the mothers, appear to be associated
with atopic sensitization early in life, as well as disturbed
relationships between the n-3 fatty acid 20:4 and the n-6 fatty
acids particularly in mature milk. On the other hand, disturbed
relationships within the individual fatty acids in the n-6 series
in human milk reflected the atopic status in the mothers. The
variations in the lipid composition of human milk could in part
explain some of the controversies regarding the protective effects
of breast-feeding against allergy.
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Identification
of a fatty acid delta6-desaturase deficiency in human skin fibroblasts.
Williard DE: Department of Biochemistry,
University of Iowa, Iowa City, IA 52242, USA; Nwankwo JO,
Kaduce TL, Harmon SD, Irons M, Moser HW, Raymond GV,
Spector AA
J Lipid Res 2001 Apr 42:501-8
Abstract
Polyunsaturated fatty acid (PUFA) utilization was investigated
in skin fibroblasts cultured from a female patient with an inherited
abnormality in lipid metabolism. These deficient human skin fibroblasts
(DF) converted 85;-95% less [1-14C]linoleic acid (18:2n-6) to
arachidonic acid (20:4n-6), 95% less [3-14C]tetracosatetraenoic
acid (24:4n-6) to docosapentaenoic acid (22:5n-6), and 95% less
[1-14C]-linolenic acid (18:3n-3) and [3-14C]tetracosapentaenoic
acid (24:5n-3) to docosahexaenoic acid (22:6n-3) than did normal
human skin fibroblasts (NF). The only product formed by the DF
cultures from [1-14C]tetradecadienoic acid (14:2n-6) was 18:2n-6.
However, they produced 50;-90% as much 20:4n-6 as the NF cultures
from [1-14C]hexadecatrienoic acid (16:3n-6), [1-14C]gamma-linolenic
acid (18:3n-6), and [1-14C]dihomo-gamma-linolenic acid (20:3n-6),
PUFA substrates that contain Delta6 double bonds. DF also contained
80% more 18:2n-6 and 25% less 20:4n-6. These results suggested
that DF are deficient in Delta6 desaturation. This was confirmed
by Northern blots demonstrating an 81;-94% decrease in Delta6-desaturase
mRNA content in the DF cultures, whereas the Delta5-desaturase
mRNA content was reduced by only 14%. This is the first inherited
abnormality in human PUFA metabolism shown to be associated with
a Delta6-desaturase deficiency. Furthermore, the finding that
the 18- and 24-carbon substrates are equally affected suggests
that a single enzyme carries out both Delta6 desaturation reactions
in human PUFA metabolism.
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Polyunsaturated
fatty acids in school children in relation to allergy and serum
IgE levels.
Yu G: Department of Health and Environment, Linköping University,
Sweden; Björkstén B
Pediatr Allergy Immunol 1998 Aug 9:133-8
Abstract
Altered composition of polyunsaturated fatty acids (PUFA) has been
observed in allergic individuals and it has been proposed that this
is due to an impairment of delta-6-desaturase activity. We have
studied the composition of PUFA in serum phospholipids in twenty-two
12-15 year old children with asthma and/or allergic dermatitis and
23 non-atopic controls of similar age. The relative levels of
docosahexaenoic acid (DHA, C22:6n-3) and total n-3 long-chain
polyunsaturated fatty acids (LCP) were lower (1.46% +/- 0.54
vs. 1.90% +/- 0.58, P = 0.01 for DHA and 2.34% +/- 0.67 vs. 2.80%
+/- 0.77, P < 0.05 for total n-3 LCP) and the ratio of total
n-6 to n-3 LCP was higher (P < 0.01) in the allergic children
than in the controls. In addition to these differences, the relative
levels of docosapentaenoic acid (DPA, C22:5n-3) and the ratio of
arachidonic acid (AA, C20:4n-6) to dihomo-gamma-linolenic acid (DHGLA,
C20:3n-6) were also lower in the 12 allergic children with positive
skin prick test, as compared with the SPT negative children
(both P < 0.05). In non-allergic children, the levels of total
n-3 correlated with n-6 LCP (r = 0.76, p < 0.001). Furthermore,
the n-3 LCP, i.e. EPA, DPA and DHA, correlated significantly with
each other (r = 0.52-0.78, all p < 0.01) and correlated with
n-6 LCP, i.e. C20:2, DHGLA and AA respectively (r = 0.56-0.83, all
P < 0.01). Most of these correlations were absent in allergic
children. Higher levels of C20:2n-6 and lower levels of eicosapentaenoic
acid (EPA, C20:5n-3) were recorded in 11 allergic children with
serum IgE above the median level (56 kU/l), as compared to 11
with lower IgE levels (both P < 0.05). Furthermore, the levels
of C20:2n-6 correlated with the IgE levels in the children (r =
0.65, P = 0.001). The findings could not confirm an impaired
delta-6-desaturase activity in allergic school children and suggest
that a disturbance of LCP metabolism is associated with allergic
diseases. |
The changes
of lymphocyte membrane receptors in bronchial asthma and atopic
dermatitis in pediatric patients receiving treatment with polyenic
fatty acids.
Gorelova JYu: Institute of Nutrition, Moscow, Russia; Semikina EM
Z Ernahrungswiss 1998 37 Suppl 1:142-3
Abstract
The influence of a diet supplemented with n-3 PUFA on the
immune status of children with atopic dermatitis and asthma was
investigated. The results of the investigation have shown the
improvement of cell immunity along with a decrease in the clinical
manifestation of the disease. n-3 PUFA could be used as immunocorrectors
in combination with pathogenic treatment of children with allergic
diseases. |
A double-blind,
randomized, placebo-controlled trial of n-3 versus n-6 fatty acid-based
lipid infusion in atopic dermatitis.
Mayser P: Department of Dermatology, Center for Dermatology and
Andrology, Justus-Liebig-University, Giessen, Germany; Mayer K,
Mahloudjian M, Benzing S, Krämer HJ, Schill WB, Seeger W, Grimminger
F
JPEN J Parenter Enteral Nutr 2002 May-Jun 26:151-8
Abstract
BACKGROUND: In the involved epidermis of patients with atopic dermatitis,
changes in the metabolism of eicosanoids with increased quantities
of the arachidonic acid (AA)-derived lipoxygenase products have
been observed. Free eicosapentaenoic acid (EPA), a fish oil-derived
alternative (n-3) fatty acid, may compete with AA, resulting in
an anti-inflammatory effect. METHODS: In a 10-day double-blind,
randomized, placebo-controlled trial, 22 patients hospitalized
for moderate-to-severe atopic dermatitis were randomly assigned
to receive daily infusions of either a n-3 fatty acid-based
lipid emulsion (fish oil, 10%; 200 mL/d) or a conventional n-6-lipid
emulsion (soybean oil, 10%; 200 mL/d). Topical treatment was restricted
to emollients. The severity of disease was evaluated daily with
scoring of erythema, infiltration, and desquamation and by subjective
patient scoring of clinical manifestations. In addition, plasma-free
and total-bound fatty acids and the composition of membrane fatty
acids in blood cells (thrombocytes, granulocytes, and erythrocytes),
lipid mediators from isolated neutrophils and platelets, and lymphocyte-activation
parameters were determined. RESULTS: Twenty patients completed
the trial. Marked improvement from baseline was seen in both
groups. On days 6, 7, 8, and 10, disease severity score-defined
as the sum of all scores-was more pronounced (p < .05) in the
n-3 group compared with the n-6 group. Free arachidonic acid
in plasma did not change substantially in both groups, whereas plasma-free
EPA, total-bound EPA, and the membrane EPA/AA ratio markedly increased
in response to n-3-lipid infusion. In parallel, EPA-derived
lipid mediators appeared, whereas lymphocyte functions were unaffected.
In the post-treatment period (2/4 weeks), relapse was observed in
some patients after n-3 psoralene-ultraviolet A (PUVA) infusion,
whereas there was a marked long-term improvement in the n-6 group.
CONCLUSIONS: IV n-3-fatty acid administration is effective in
acutely improving the severity of atopic dermatitis, paralleled
by changes in plasma and membrane fatty acid composition and lipid
mediator synthesis. The long-term beneficial effects of IV n-6 fatty
acids should be evaluated further. |
Dietary
supplementation with very long-chain n-3 fatty
acids in man decreases expression of the interleukin-2 receptor
(CD25) on mitogen-stimulated lymphocytes from patients with inflammatory
skin diseases.
Søyland E: Section for Dietary Reasearch, University of Oslo,
Norway; Lea T, Sandstad B, Drevon A
Eur J Clin Invest 1994 Apr 24:236-42
Abstract
T-cell activation and cytokine production play an important
role in several chronic inflammatory diseases. Because n-3 fatty
acids exert beneficial effects on the clinical state of some of
these diseases, we examined the effect of dietary supplementation
of n-3 fatty acids on T-cell proliferation, expression of CD25 (interleukin-2
receptor alpha-chain), secretion of interleukin-2, interleukin-6
and tumour necrosis factor from T-cells from patients
with psoriasis and atopic dermatitis. During 4
months, 21 patients supplied 6 g of highly concentrated ethyl esters
of EPA and DHA in gelatin capsules daily to their diet.
In the control group 20 patients supplied 6 g per day of corn oil
in gelatin capsules to their diet. Eicosapentaenoic acid (20:5,
n-3) of serum phospholipids increased from 14 (min 4-max 42) to
81 (min 59-max 144) mg l-1 (P < 0.01) in patients with atopic
dermatitis receiving n-3 fatty acids, and from 25 (min 7-max 66)
to 74 (min 46-max 142) mg l-1 (P < 0.01) in patients with psoriasis,
whereas docosahexaenoic acid (22:6, n-3) increased from 65 (min
46-max 120) to 92 (min 54-max 121) mg l-1 (P < 0.05) and from
81 (min 38-max 122) to 92 (min 63-max 169) mg l-1 (NS) in atopic
and psoriatic patients, respectively. The changes in the serum phospholipid
fatty acid profile in the groups receiving n-3 fatty acids, correlate
to the dietary intake of corresponding fatty acids. |
Effects
of dietary supplementation of fish oil on neutrophil and epidermal
fatty acids. Modulation of clinical course of psoriatic subjects.
Ziboh VA, Cohen KA, Ellis CN, Miller C, Hamilton TA, Kragballe K,
Hydrick CR, Voorhees JJ
Arch Dermatol 1986 Nov 122:1277-82
Abstract
Findings from an eight-week fish oil-supplemented diet given
to 13 psoriatic patients demonstrated that eicosapentaenoic
acid (20:5,n3 [EPA]) and docosahexaenoic acid (22:6,n3 [DCHA]) are
rapidly incorporated into the sera, neutrophils, and epidermis of
participating patients, and that the incorporation of EPA and DCHA
into epidermal lipids increased with weeks of supplementation with
minimal alteration of arachidonic acid (AA) in the epidermal lipids.
Global clinical evaluation showed that eight patients demonstrated
mild to moderate improvement in their psoriatic lesions. Improved
clinical response correlated with high EPA/DCHA ratios attained
in epidermal tissue specimens. These findings underscore the need
for further investigations into the role of dietary n3 fatty acids,
particularly the possibility of pentaenoic acid as a potential protective
agent and/or therapeutic adjunct for the clinical management of
psoriasis. |
n-3 fatty
acids in psoriasis.
Mayser P: Department of Dermatology and Andrology, Justus Liebig
University, Giessen, Germany; Grimm H, Grimminger F
Br J Nutr 2002 Jan 87 Suppl 1:S77-82
Abstract
Increased concentrations of free arachidonic acid (AA) and its proinflammatory
metabolites have been observed in psoriatic lesions. Replacement
of arachidonic acid by alternative precursor polyunsaturated fatty
acids (PUFA), especially eicosapentaenoic acid (EPA), which can
be metabolized via the same enzymatic pathways as AA, might be a
therapeutic option in psoriasis. However the results of studies
evaluating the therapeutic benefit of dietary fish oil have been
conflicting and not clearly dose-dependent. To overcome the slow
kinetics and limited availability of oral supplementation, we have
performed three studies to assess the efficacy and safety of an
intravenously administered fish oil derived lipid emulsion on different
forms of psoriasis. Patients received daily infusions of either
an n-3 fatty acid-based lipid emulsion (Omegaven) or a conventional
n-6 lipid emulsion (Lipoven) in different time and dose regimens.
In addition to an overall assessment of the clinical course of psoriasis,
EPA- and AA-derived neutrophil 5-lipoxygenase (LO)--products, thromboxane
(TX) B2/B3, PAF and plasma free fatty acids were investigated. Treatment
with n-3 fatty acids resulted in a considerably higher response
rate than infusion of n-6 lipids. A more than 10-fold increase in
neutrophil EPA-derived 5-LO product formation was noted in the n-3
group, accompanied by a rapid increase in plasma-free EPA within
the first days. In conclusion, intravenous n-3-fatty acid administration
causes reduction of psoriasis, which may be related to changes in
inflammatory eicosanoid generation. The rapidity of the response
to intravenous n-3 lipids exceeds by orders of magnitude the hitherto
reported kinetics of improvement of psoriatic lesions upon use of
oral supplementation. |
Effects
of dietary supplementation with polyunsaturated ethyl ester lipids
(Angiosan) in patients with psoriasis and psoriatic arthritis.
Lassus A: Department of Dermatology, University Central Hospital,
Helsinki, Finland; Dahlgren AL, Halpern MJ, Santalahti J, Happonen
HP
J Int Med Res 1990 Jan-Feb 18:68-73
Abstract
A total of 80 patients with chronic, stable psoriasis, 34
of whom also had psoriatic arthritis, were treated with
1122 mg/day eicosapentaenoic acid ethyl
ester and 756 mg/day docosahexaenoic acid ethyl ester.
Before the study and after 4 and 8 weeks
of treatment a Psoriatic Association scoring
index (PASI) score was assessed.
Before treatment the mean PASI score was 3.56, after 4 weeks
1.98 and after 8 weeks 1.24; the decrease in the score was highly
significant (P less than 0.001). The degree of pruritis
decreased most rapidly, followed by scaling and induration of the
plaques, and erythema was most persistent.
At the end of the trial, seven patients were completely healed
and in 13 other patients more than 75% healing was observed but
in 14 patients the result was poor. The majority of patients
with psoriatic arthritis reported a subjective improvement in joint
pain during the study. It is concluded that polyunsaturated ethyl
ester lipids may be useful for the treatment of psoriasis and psoriatic
arthritis and may provide an important adjuvant to standard therapy
of both conditions. |
Effect
of regular consumption of oily fish compared with white fish on
chronic plaque psoriasis.
Collier PM: Department of Dermatology, Westminster Hospital, London,
UK; Ursell A, Zaremba K, Payne CM, Staughton RC, Sanders T
Eur J Clin Nutr 1993 Apr 47:251-4
Abstract
The influence of dietary advice on the severity of chronic plaque
psoriasis was studied in 18 patients. Medication was
standardized in all patients who were advised to eat 170 g white
fish daily for a 4 week run-in period. Then the patients were randomized
either to continue with the white fish diet or to substitute
170 g oily fish daily for 6 weeks. At the end of this second
period the diets were reversed for a further 6 weeks. The oily
fish but not the white fish diet led to a modest clinical
improvement (11% and 15%, P < 0.01) which was accompanied
by a rise in plasma eicosapentaenoic acid (20:5n-3) concentrations.
It is concluded that dietary advice to increase the daily intake
of oily fish is a useful adjunct in the treatment of psoriasis.
The fish that should be recommended include mackerel, sardine, salmon,
pilchard, kipper and herring. |
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