The influence of leptin on Th1/Th2 balance in obese children with asthma

Abstract

Objective: In individuals with asthma, obesity induces the production of leptin and is associated with disease severity. Our objective was to evaluate the levels of serum leptin and their effect on Th1/Th2 balance in obese and non-obese children with asthma, as well as to investigate the association between serum leptin levels and clinical outcomes. Methods: We evaluated 50 atopic children with physician-diagnosed moderate-to-severe persistent asthma and 20 controls. The children with asthma were divided into two groups, by body mass index percentile: obese (n = 25) and non-obese (n = 25). From all subjects, we collected peripheral blood samples in order to determine the levels of leptin, IFN-γ, and IL-4. Asthma severity was assessed by an asthma symptom score, and the results were correlated with the parameters studied. Results: Serum leptin levels were significantly higher in the obese asthma group than in the non-obese asthma group, as well as being significantly higher in the children with asthma than in the controls, whereas IFN-γ levels were significantly higher and IL-4 levels were significantly lower in the obese asthma group than in the non-obese asthma group. In addition, the obese asthma group showed higher asthma symptom scores and significantly lower FEV 1 (% of predicted) than did the non-obese asthma group. There was a significant positive correlation between leptin and IFN-γ levels only in the obese asthma group. Conclusions: Although leptin is involved in the pathogenesis of asthma in obese and non-obese children, its effect is more pronounced in the former. In the presence of high leptin levels, only obese children with asthma exhibited Th1 polarization, with higher IFN-γ levels and greater asthma severity.Keywords: Leptin; Asthma; Interferon-gamma; Interleukin-4. ResumoObjetivo: A obesidade induz a produção de leptina em asmáticos e está associada à gravidade da doença. Nosso objetivo foi avaliar os níveis de leptina sérica e seu efeito no equilíbrio Th1/Th2 em crianças asmáticas obesas e não obesas e investigar a associação desses níveis com desfechos clínicos. Métodos: O estudo envolveu 50 crianças atópicas com diagnóstico médico de asma persistente moderada a grave e 20 controles. Os asmáticos foram agrupados como obesos (n = 25) e não obesos (n = 25) de acordo com o percentil do índice de massa corpórea. Amostras de sangue periférico foram coletadas de todos os sujeitos, e os níveis de leptina, IFN-γ e IL-4 foram determinados. A gravidade da asma foi avaliada por um escore de sintomas de asma, e os resultados foram correlacionados com os parâmetros estudados. Resultados: Os níveis séricos de leptina foram significativamente maiores nos asmáticos obesos do que nos asmáticos não obesos, assim como nos asmáticos comparados aos controles, enquanto os níveis de IFN-γ foram significativamente maiores e os de IL-4 foram significativamente menores nos asmáticos obesos do que nos asmáticos não obesos. Os asmáticos obesos tiveram maiores escores de sintomas de asma e VEF 1 (% do previsto) si...

Important non‐disease‐related determinants of exhaled nitric oxide levels in mild asthma – results from the Swedish GA2LEN study

“…The association with weight is in line with results from univariate analysis from healthy adults, reported by Jo et al . This could in theory be explained by Th1‐polarisation and lower levels of Th2‐cytokines seen in obese patients with asthma that could lead to lower FeNO levels. However, this relation became statistically non‐significant after adjustments in the present study, and it was mainly explained by gender differences in the report of Jo et al .…”

Serum Ghrelin Levels in Saudi Obese Asthmatic School-Children—Correlation with Interleukin-4, Interleukin-5, and Interleukin-21

“…In a previous study, leptin levels in obese and non-obese asthmatic children were higher than in matched non-asthmatic controls. Nevertheless, elevated leptin values in the same study were positively correlated with high levels of interferon (INF)-g (Th1 cytokine) that were attributed to inflammation around the bronchioles and the aggravation of severe asthma [22]. Ghrelin is expected to have anti-inflammatory actions that might suppress proinflammatory cytokines such as tumor necrosis factor (TNF)-α, IL-1β and IL-6, which are involved in the inflammation and pathogenesis of asthma [25,26].…”

“…In accordance with the guidelines of The Saudi Initiative for Asthma [20] and the Global Initiative for Asthma [21], asthma was diagnosed based on a history of recurrent or chronic chest symptoms such as coughing, wheezing, difficulty breathing, and chest tightness that demonstrated clinical reversibility with short-acting bronchodilator treatment. Symptom score in children with asthma was assessed according to a six-domain asthma symptom score that includes dyspnea, tightness in the chest, wheezing during the day, wheezing during the night, and daily performance [22].…”

The Effects of Zinc Supplementation on Immune Response of Obese Children With Family History of Atopy

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