Contaminantes aéreos y sus efectos en pacientes alérgicos del Valle de Caracas / Air pollutants and their effect in allergic patients in the Valle of Caracas

La prevalencia y severidad de las enfermedades alérgicas está aumentando de manera alarmante a nivel mundial. Las principales enfermedades emergentes son las que se expresan a nivel del tracto respiratorio, por inhalación de contaminantes locales y regionales a causa de las alteraciones climáticas que se observan y registran en nuestro planeta. Numerosos artículos sobre el cambio climático y sus efectos en la reacción alérgica han aparecido en la literatura reciente, específicamente en relación con la exposición alergénica, incluyendo tipo, frecuencia, ubicación geográfica, cantidad y cualidad, en particular granos de polen debido a cambios del tiempo y duración de la estación floral de las plantas alergénicas. Las alteraciones en la vegetación son indicadores muy sensibles del cambio climático. El aumento de CO2incrementa a su vez la biomasa vegetal, la distribución de las plantas, la producción de polen y en un mayor grado, su capacidad alergénica. Otros efectos importantes se observan en la respuesta inflamatoria de la población a riesgo hacia proteínas alimentarias, alergenos de insectos y reactividad cruzada entre antígenos. Agentes como el ozono, el material particulado, el dióxido de azufre y las partículas diesel se conocen que forman especies reactivas de oxígeno, tales como el anión superóxido, el peróxido de hidrógeno y los radicales hidroxilos. Las especies reactivas de oxígeno pueden dañar proteínas, lípidos y directamente el ADN. Los contaminantes producen un efecto reversible en la función pulmonar, en el mecanismo inflamatorio de las vías aéreas, hiper-reactividad bronquial, comprometen la función inmunológica, aumentan la incidencia y exacerbación de enfermedades pulmonares como el asma y su tasa de mortalidad.

Estos agentes estimulan además, el aumento de la permeabilidad a nivel de las mucosas aéreas, lo que facilita el pase rápido de los antígenos sensibilizantes hacia capas de tejido más profundas y por consecuencia, facilitan una mayor interacción con las células del sistema inmune. Se ha propuesto un sin ergismo entre las partículas diesel y los aereo alergenos a nivel de la mucosa respiratoria alta de humanos, estimulando la producción de IgE específica por la producción de citoquinas Th2. Esto se explica por las propiedades adyuvantes de estas partículas asociadas a un aumento en la prevalencia de asma a nivel mundial, hecho relacionado al uso más frecuente de diesel en el parque automotor. Publicaciones aisladas sobre contaminantes aéreos en Venezuela, estimula la estructuración de un proyecto multidisciplinario por fases (I, II y III) de investigación, con el fin de determinar la posible influencia de los mismos, en la aparición y exacerbación de enfermedades alérgicas a nivel del tracto respiratorio, en especial los pacientes que sufren de asma en el área metropolitana de Caracas...

The prevalence and severity of allergic diseases is increasing at alarming rate worldwide. The principal emerging diseases are located in therespiratory tractdue to inhalation of localand regional pollutants as aconsequence observed and registered climate changes in our planet. Numerous articles about climate change and its effect on the allergic reaction have appeared in recent literature, specifically in relation to the allergen exposure including: type, frequency, geographical location, quantity and quality, in particular pollen grains due to changes in the weather and duration of the flowering season of allergenic plants, Changes in the vegetation are very sensitive indicators of climate change. The increase in CO2 increases the plant biomass, plant distribution, pollen production and in great degree its allergenic capacity. Other important effects are observed in the inflammatory response to proteins, insect allergens and crossed reactivity between allergens of the population at risk. Agents such as the ozone, material particles, sulphur dioxide and diesel particles are known as reactive oxygen species, such as superoxide anion, hydrogen peroxide and hydroxyl radicals. The reactive oxygen species can damage proteins, lipids an DNA directly. The pollutants produce a reversible effect on pulmonary function, the inflammatorymechanismoftheairways,producebronquial hyperreactivity, compromise the immunological function, increase the incidence and exacerbation of pulmonary diseases such as asthma and its mortality rate.

These agents also stimulate the increase in permeability of the mucosa airway, which facilitates the rapid pass and entry of antigens to the deeper layers and as a result facilitate the interaction with immune system cells. A synergism between diesel particles and air allergens in the upper human mucosa respiratory tract has been proposed and it is thought that Th2 citokines stimulate the production of specific IgE. This can be explained by the properties of these particles and their association with an increase in the asthma prevalence worldwide and the fact that there has been a more frequent use of diesel in vehicles. Publications about air pollutants in Venezuela promote that instauration of an interdisciplinary project of investigation phases (I, II, III), in order to determine their possible influence in the development and exacerbation of allergic diseases in the respiratory tract, especially in asthma patients from the metropolitan Caracas area....

Nitric oxide and superoxide anion production in monocytes from children exposed to arsenic and lead in region Lagunera, Mexico.

We evaluated in Mexican children environmentally exposed to arsenic and lead monocyte nitric oxide (NO) and superoxide anion production in response to direct activation with interferon-gamma (IFN-gamma) + lipopolysaccharide (LPS). The integrity of Th1-regulated cellular immune response when monocytes were indirectly activated was also evaluated. Most children lived near a primary lead smelter. Lead and arsenic contamination in soil and dust by far exceeded background levels. As levels in water were between 10 and 30 ppb. Most children (93%) had urinary arsenic (AsU) concentrations above 50 microg/l (range 16.75-465.75) and 65% had lead blood levels (PbB) above 10 microg/dl (range 3.47-49.19). Multivariate analyses showed that NO production in monocytes activated indirectly was negatively associated with both PbB and AsU. Superoxide production in directly activated monocytes was negatively associated with AsU but positively associated with PbB. The models including the interaction term for AsU and PbB suggested the possibility of a negative interaction for NO production and a positive interaction for superoxide. There were indications of differential gender-based associations, NO production in indirectly activated monocytes obtained from girls was negatively associated with AsU but not with PbB. Superoxide production was positively associated with PbB in both directly and indirectly activated monocytes from boys but the latter was negatively associated with AsU. These effects are consistent with immune system abnormalities observed in human populations exposed to Pb or As. Further studies in larger populations are required to characterize As and Pb interactions and the mechanism(s) underlying the observed effects.