Thursday, October 23, 2008

Nutritional therapy of the respiratory allergy

Nutritional therapy of the respiratory allergy

The allergy is defined like the abnormal reaction of a subject with respect to an antigen (foreign substance at the organization likely to cause the formation of specific antibodies by the organization). The respiratory allergy is an exaggerated and harmful reaction occurring after antigenic sensitizing by a pneumallergene. The pneumallergene is defined as an inhaled substance able to sensitize the organization of certain individuals and to determine, at the time of its reintroduction, of the pathological demonstrations, in particular of the breathing apparatus but also of the eyes (on the level of the conjunctive ones)The breathing apparatus is reached on all the levels of penetration of pneumallergene; the largest particles (> with 13 microns) such as the grains of intact pollens, are retained by the nasal filter and determine isolated rhinitides and rhinosinusites; finest (= with 3 microns) penetrate in the deep lung, final bronchioles and the cells and involve extrinsic alveolites; the bronchial tree is exposed to the particles of intermediate size thus determining bronchial asthmas. The mucous lesions are identical nasal stage on the bronchial floor; oedema, hypersecretion of mucusThe dust of house is the prevalent pneumallergene. It intervenes via its components in the forefront of which the acarina are located. The acarina are found at 70% of the asthmatic children. They are responsible for primarily evening and night crises, started by the handling of dust, depend on the internal moisture of the houses with a greater abundance at the end of the summer, autumn, and at the beginning of the winter, a disappearance above 1500 Mr.Pollens are with the second rank of pneumallergenes. To be allergisants, they must be in sufficient quantity in the air. The early season of pollens of trees extends from mid-December in mid-April in the South, of the mid-February in mid-May in Ile de France., with a majority of pollen in March and April. The great season of pollens the graminaceous ones extends from at the end of April at the beginning of July in the South, and from mid-May at mid-July in the Ile de France. The late season from July at the end of September that of is made, in particular the armoise, the chénopode but also the ambrosia collected in the region of Lion. The season of the pellitories extends from at the end of April at the end of September in the South.The superficial body growths of animals occupy the third rank of pneumallergenes, they take an increasingly large importance with the increase in the number of the pets (dogs, cats, hamster, guinea-pigs, birds…). They involve rhinitides and conjunctivites, but also of very severe asthmas sometimes.
The mechanism of the respiratory allergy is divided by two stages.The first stage is sensitizing. The pneumallergene dice its penetration in the breathing apparatus, by the macrophages or the cells of Langerhans. Thus modified, these cells presents it in the shape of a “superallergene” to the lymphocyte T. Those, thus stimulated, secrete cytokines (IL-4) and activate the lymphocytes B. The latter then secrete specific antibodies of the allergen, in particular of immunoglobulins of the type E. These IgE set on the receivers in particular strong affinity, laid out on the membrane of the mastocytes and the basophilic ones.The second phase is the allergic reaction itself. It takes place at the time of the reintroduction of pneumallergene in the breathing apparatus. This one is fixed then on two specific molecules of IgE fixed on the membrane of the mastocytes and the basophilic ones. This connection involves a process of degranulation cellular. Three types of substances known as “mediating” are then released by these cells:- preformed substances, contained in the cytoplasmic granules: histamine coupled with heparin, factors chimiotactic and many enzymes of which the tryptase;- newly formed substances, by activation of the membrane phospholipases, the cyclooxygénases and the lipooxygénases: production of prostaglandins, leucotrienes (inductor of brochonconstriction) and of PAF (plate factor of activation)- cytokines. The whole of these various substances has a fast effect, initiated by broncho-spastic histamine and proinflammatoire, and a delayed effect, the local surge of leucocytes (white globules) under the influence of the factors chimiotactic. These leucocytes, then activated, release from new substances proinflammatoires spamogenes and poisons. The target bodies concerned with the reaction are mainly the nasal mucous membrane (source of rhinitis), the bronchial mucous membrane (at the origin of an asthma attack), the conjunctive mucous membrane (causing a conjunctivitis)
The treatment of the respiratory allergies apply to the lesions of the body targets either by being opposed to the degranulation mastocytes, or as agonists of histamineCromoglycate de Sodium, by its antidégranulants effects, prevents the reaction to IgE mediation as well immediate as delayed, inflammatory on the level of the mucous membranes interested by the allergenic provocation.The vitamin C or ascorbic acid is a water-soluble antioxydant essential with the level of the pulmonary parenchyma. It is the principal antioxydant of the bronchial mucous membrane, protecting this one at the same time from endogenous and exogenic oxidants (polluting, tobacco…). It can trap the free radicals produced at the time of the degranulation of the mastocytes occurring during the allergic reaction. It has direct an antihistamine effect by nonenzymatic degradation of histamine. Lastly, it is indirectly antibronchospastic by inhibition of the synthesis of F2 the inductive prostaglandins of bronchoconstriction. Also, deficiency in vitamin C is a risk factor of asthma. The contribution in vitamin C and the rate of vitamin C of the serum are correlated with the volume of expiry forced during one second (VEF1) and are conversely correlated with the presence of sibilants. The administration of vitamin C decreases the effect of histamine inhaled on the respiratory tracts at the subjects reached of allergic rhinitis. It decreases the frequency and the severity of the asthma attacks. It makes it possible to reduce the incidence of asthma by reduction in the hyperreactivityThe vitamin E is a liposoluble antioxydant. A weak contribution in vitamin E is a risk factor of asthma. The administration of vitamin E induces a reduction in the symptoms of asthma and allows a reduction of the use of the steroids.Quercetin inhibits the bronchial reactivity by reduction of the PAF (plate factor of activation. It has antioxydatives properties and anti-inflammatory drugs.The bromélaïne has a proinflammatoire effect by stimulation of synthesis E1 the prostaglandin and prevents plate aggregationDuring the asthmatic disease, one raised a blocking of the synthesis of the nicotinamide starting from tryptophan. This blocking can be corrected by the supplementation in long-term B6 vitamin. The theophylline catch (used as treatment of asthma) involves a reduction of the serum pyridoxal-phosphate concentration (B6 Vitamin activated). The administration of B6 reduces the frequency and the gravity of the sibilants and the asthma attacks. It makes it possible to lower the catch of bronchodilatator and corticoids. It acts like releasing muscular. The B6 vitamin reduces intolerance to the glutamate (syndrome of the Chinese restaurant)The administration of B12 vitamin attenuates the bronchospasme, and makes it possible to reduce the sibilants at the time of an intolerance to sulphites. The B12 vitamin by catabolisant sulphate sulphites, decreases over-sensitiveness with sulphites.A weak zinc contribution is a risk factor of asthma and over-sensitiveness to chemical substances. The serum zinc rate is lowered in asthma and the allergy. The activity in superoxyde dismutase in plate Cuivre-Zinc is higher at the asthmatic ones.60% of athematic and 50% of the subjects making an asthma attack low have a serum magnesium rate. The athematic subjects low have a leucocytic magnesium compared to the healthy subjects. Asthma increases the requirements out of magnesium. Magnesium deficiency is correlated with the allergy, with the ignition, and to the bronchial hyperactivity the more so as the treatment by beta-agonistes (usually used during the asthma attack) lowers the serum magnesium concentration and deteriorates the passage of magnesium between the compartments extracellular and intracellular. Magnesium deficiency supports the sensitivity of the smooth muscles to the agents vasoconstricteurs and contributes to occurred of pulmonary complications. Many effects of magnesium are related to its antagonism with respect to calcium and magnesium deficiency involves an increase in the cellular content calcium, factor of vasoconstriction and plate hyperagregability. The magnesium administration involves a reduction of the bronchial hyperreactivity. It reduces the production of anion superoxide by the polynuclear ones activated. It attenuates the macrophagic respiratory explosion at the asthmatic one. It makes it possible to stop the bronchoconstriction, to increase the peak-flow (expiratory flow of point maximum), the FEV1 and to reduce the sibilants.The reduction of the selenium contributions, of the serum concentrations and selenium érythrocytaires, as well as the reduction of the activity of the glutathion dependent peroxidase selenium are risk factors of asthma. The selenium contribution is conversely correlated the incidence of asthma. The asthmatic ones and more generally the allergic subjects have low contents selenium. The selenium deficiency involves a reduction of the activity of the glutathion peroxidase, a rise in thromboxane A2 (proagrégant and vasoconstrictor), an increase in plate aggregation and a reduction in prostacyclin or prostaglandin I2.Chez the asthmatic one, the selenium supplementation reduces plate aggregation by increase the activity of the glutathion peroxidase which plays a key role in the defense system antioxydant.Ginkgo biloba is an Asian plant traditionally used in Chinese medicine in the treatment of asthma and the bronchial one. It contains ginkgolides, flavonoïdes and terpenes. The ginkgolides are antagonists of the PAF (plate factor of activation) inductive of the degranulation. The extract of Ginkgo biloba has antioxydant properties. The extract is anti-inflammatory drug by modulating the metabolism of the eicosanoïdes on the one hand, by inhibition of the stimulation of the E2 prostaglandins and the plate secretion of beta-thromboglobuline, and on the other hand, by activation partial of the receiver beta-adrénergique. Thus, the extract of Ginkgo biloba is opposed to the bronchoconstriction and reduces the bronchial hyperreactivity.

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