RESUMO
Many studies have demonstrated that vitamin A deficiency (VAD) affects the immunomodulated response mediated by cytokines. However, these studies are controversial. The purpose of the present study was to analyze Interleukin-10, gamma-Interferon and vitamin A serum concentrations in adolescents. Seventy three female, not pregnant adolescents (15.95 +/- 1.10 years old), of a low socioeconomic condition were studied. Serum retinol was determined by HPLC using the Bieri method. International reference standards were considered to define VAD (serum retinol < 20 microg/dL), risk of VAD (20-30 microg/dL) and vitamin A sufficiency (>30 microg/dL). Serum concentrations of Interleukine-10 (IL-10) and gamma-Interferon (gamma-IFN) were detected by an ELISA method (pg/mL). The data were analyzed using the SAS/STAT statistical program; the results were presented as mean +/- Standard deviation and the differences between mean values were analyzed by the ANOVA test. The prevalence of VAD in adolescents was 6.85% (serum retinol <20 microg/dL) and 41.10% adolescents had VAD risk (20-30 microg/dL). Adolescents with VAD showed a significant increase of gamma-IFN serum concentration (p = 0.01). Correlation between serum retinol and gamma-IFN was r = -0.29 (p = 0.01). Adolescents represent a VAD risk group. Low serum levels of retinol were correlated with high levels of gamma-IFN, this cytokine has been associated with chronics inflammatory processes and it can contribute to increase the morbidity and mortality in this population.
Assuntos
Interferon gama/sangue , Interleucina-10/sangue , Deficiência de Vitamina A/epidemiologia , Vitamina A/sangue , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Valores de Referência , Risco , Estudos de Amostragem , Fatores Socioeconômicos , Venezuela/epidemiologiaRESUMO
Diversas investigaciones han demostrado que la deficiencia de vitamina A (DVA) afecta la respuesta inmunoreguladora mediada por las citocinas; sin embargo, estos estudios son controversiales. El objetivo de este estudio fue analizar las concentraciones séricas de Interleucina-10 (IL-10) e Interferón-gamma (IFN-gamma) y vitamina A en adolescentes femeninas. Se estudiaron 73 adolescentes femeninas (15,95 ± 1,10 años de edad), no gestantes según fecha de última regla, escolarizadas, de baja condición socioeconómica. Se determinó la concentración sérica de retinol por HPLC según el método de Bieri, utilizando los patrones de referencia internacional que definen DVA < 20µg/dL, riesgo de DVA 20-30µg/dL y suficiencia de vitamina A >30µg/dL. Las concentraciones séricas de las citocinas (IL-10 e IFN-gamma) fueron determinadas con el método de ELISA en pg/mL. Los datos fueron analizados con el programa estadístico SAS/STAT, expresados como promedio ± Desviación estándar y las diferencias entre los valores promedio de las variables fueron analizadas con ANOVA. Se encontró que la prevalencia de DVA en las adolescentes fue de 6,85 por ciento (Retinol sérico < 20µg/dL) y el 41,10 por ciento se encontraban en riesgo de DVA (20-30µg/dL). Las concentraciones séricas de IFN-gamma mostraron valores significativamente más altos en las adolescentes con retinol sérico < 20µg/dL (p = 0,01), observándose una correlación negativa significativa (r = -0,29; p = 0,01) entre ambas variables. La adolescencia representa un grupo de riesgo de DVA. En este trabajo encontramos que bajos niveles séricos de retinol se correlacionaron con un incremento en los niveles de IFN-gamma, citocina que se ha asociado con la presencia de procesos inflamatorios crónicos que pueden incrementar la morbilidad y mortalidad en esta población.
Assuntos
Humanos , Feminino , Adolescente , Citocinas , Interleucina-10 , Interleucina-18 , Vitamina A , Medicina , VenezuelaRESUMO
Estudios realizados en humanos y animales han mostrado que la baja ingesta de vitamina A puede provocar anemia, sin embargo, aún no se conocen los mecanismos etiopatogénicos involucrados en tal proceso, lo cual puede ser debido a las complejas interacciones de los micronutrientes entre sí y con el sistema inmune. El objetivo del presente estudio fue analizar las concentraciones séricas del Interferón gamma (IFN- g) y la Interleucina 10 (IL-10) en niños anémicos y no anémicos según el estado nutricional de la vitamina A. Para ello, se estudiaron 53 niños eutróficos (45-77 meses; F=29, M=24), procedentes de Maracaibo-Venezuela, en quienes se evaluó: la presencia de anemia mediante el análisis de la concentración de hemoglobina, según los criterios de la OMS (Hb<110g/L <60 meses, Hb<115g/L >60 meses); y el estado de la vitamina A por la técnica de Citología de Impresión Conjuntival (CIC), considerando la prueba de CIC Normal=suficiencia de vitamina A y CIC Anormal=DVA. Asimismo, fueron determinadas las concentraciones séricas de las citocinas (IFN-gamma e IL-10) en pg/mL con el método de ELISA. Los datos fueron analizados con el programa estadístico SAS/STAT, los grupos fueron comparadas aplicando ANOVA (p<0,05). En nuestros resultados la prevalencia de anemia observada fue de 75,50 por ciento; DVA 50,94 por ciento y de Anemia+DVA 35,86 por ciento. Los niños anémicos con DVA mostraron valores séricos significativamente más bajos de IFN- g e IL-10 que el resto de los grupos. Esta alteración de los complejos mecanismos regulatorios del sistema inmunitario pudiera ser un elemento responsable de los trastornos en la formación de los eritrocitos
Assuntos
Humanos , Masculino , Feminino , Criança , Anemia , Interferon gama , Vitamina A , Fenômenos Fisiológicos da Nutrição , Pediatria , VenezuelaRESUMO
Studies done with human and animals have shown that the diminished vitamin A intake can produce anemia, but the ethiopathogenic mechanism hasn't been known due to the few studies about the complex interactions between micronutrients deficiencies, immune system and cytokine productions. The objective of the present study was to analyze the serum concentration of IFN-gamma and IL-10 in anemic and non anemic children according to vitamin A nutritional status. A descriptive study of 53 euthrophic children, without infectious diseases (45-77 month old; 29 girls, 24 boys), living in a slum in Maracaibo-Venezuela. Anemia was evaluated by means of blood hemoglobin concentration analysis, standard WHO criteria for anemia were Hb < 110 g/L in <60 month old children; Hb < 115 g/L in >60 month old children. Vitamin A status was assessed by Conjunctival Impression Cytology (CIC) technique, which determines Normal CIC=Control or Abnormal CIC=VAD. The serum concentration of IFN-gamma and IL-10 (pg/mL; X +/- DE), was determined by the ELISA method. Statistical significance of differences was tested by ANOVA (p < 0.05). Prevalence of anemia was 75.50%; VAD 50.94% and anemia+VAD 35.86%. The anemic children with VAD showed significant serum values of IFN-gamma e IL-10 lower than in other groups. This alteration of the complex immunoregulatory mechanism could be responsible for dysfunction eritrhoid cell formation.
Assuntos
Anemia Ferropriva/sangue , Interferon gama/sangue , Interleucina-10/sangue , Estado Nutricional/fisiologia , Deficiência de Vitamina A/sangue , Análise de Variância , Anemia Ferropriva/epidemiologia , Antropometria , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Venezuela/epidemiologia , Vitamina A/sangue , Deficiência de Vitamina A/epidemiologiaRESUMO
Vitamin A Deficiency Disorders (VADD) have been associated with alterations of cellular differentiation, regulatory functions of the immune system and increased children morbidity and mortality rates due to acute respiratory and intestinal infections. The aim of the present study was to determine serum concentrations of Thl-Th2 cytokines in VADD children. The sample consisted of 138 children (F=72; M=66; 4-7 y old) living in slums in Maracaibo, Venezuela, with an adequate nutrition assessed by clinics and anthropometry. Vitamin A status was assessed by the Conjunctival Impression Cytology (CIC) technique following the ICEPO methodology, which determines Normal CIC = control or Abnormal CIC = VADD. The cytokines IL-10, IL-4 and IFN-gamma (pg/mL) were analyzed by the ELISA method; and IL-2 (U/mL) by the EAISA method. The Student's t test was applied to detect differences between values (p<0.05). No one child presented clinical evidence of VADD; 71 children (51.40%) exhibited normal CIC (control), whereas 67 children (48.60%) presented abnormal CIC indicative of sub-clinical manifestation of VADD. The prevalence was higher, although non significant, in females, 5-6 y old children and amerindians (51.39%, 64.18% and 60.40%, respectively). A diminished serum concentration of IL-10 was detected in VADD children, in comparison with the control group (4.41 +/- 1.27 pg/mL vs. 6.03 +/- 3.90 pg/mL) (p<0.03). The rest of studied cytokines were not significantly different with respect to control. The IL-10 diminution in VADD children would be related to the alteration of the inflammatory response at the level of respiratory and intestinal epithelia affected by infections.