RESUMEN
Zinc is required for multiple cellular tasks, and especially the immune system depends on a sufficient availability of this essential trace element. During the last decades, many studies attempted to affect the outcome of various diseases by zinc supplementation. These efforts either aimed at supporting immunity by zinc administration or at correcting a loss of zinc secondary to the disease to restore the zinc-dependent functions of the immune system. This review aims to summarize the respective findings and to discuss possible molecular mechanisms by which zinc could influence viral, bacterial, and parasitic infections, autoimmune diseases, and the response to vaccination. Zinc supplementation in diseases such as diarrhea, chronic hepatitis C, shigellosis, leprosy, tuberculosis, pneumonia, acute lower respiratory infection, and leishmaniasis seems beneficial. In contrast, the results for the common cold and malaria are still not conclusive, and zinc was ineffective in most vaccination and rheumatoid arthritis studies. For AIDS and type 1 diabetes, zinc supplementation may even be a risk factor for increased mortality or deterioration of the glucose metabolism, respectively. In these cases, zinc supplementation should be used with care and limited to clearly zinc-deficient individuals.
Asunto(s)
Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/inmunología , Enfermedades Transmisibles/tratamiento farmacológico , Enfermedades Transmisibles/inmunología , Inmunidad/efectos de los fármacos , Zinc , Animales , Enfermedades Autoinmunes/metabolismo , Disponibilidad Biológica , Enfermedades Transmisibles/metabolismo , Suplementos Dietéticos/efectos adversos , Humanos , Factores Inmunológicos/uso terapéutico , Inflamación , Mediadores de Inflamación/agonistas , Mediadores de Inflamación/inmunología , Mediadores de Inflamación/metabolismo , Ratones , Especies Reactivas de Oxígeno/agonistas , Especies Reactivas de Oxígeno/inmunología , Especies Reactivas de Oxígeno/metabolismo , Vacunación , Zinc/administración & dosificación , Zinc/efectos adversos , Zinc/metabolismo , Zinc/uso terapéutico , Compuestos de Zinc/administración & dosificación , Compuestos de Zinc/efectos adversos , Compuestos de Zinc/metabolismo , Compuestos de Zinc/uso terapéuticoRESUMEN
Dietary zinc deficiency is widespread in developing countries and is often aggravated by intercurrent acute and chronic infections. Recent studies have demonstrated that zinc supplementation can significantly reduce the morbidity and mortality of apparently well-nourished children and shorten the time to recovery from acute infectious diseases. This review summarises current knowledge of the role of zinc in childhood diarrhoea, acute respiratory infections and malaria, and its potential role in diseases associated with impaired cellular immunity, namely tuberculosis, lepromatous leprosy and leishmaniasis, and explores avenues for future research.