RESUMEN
BACKGROUND: Recent studies suggest that cytokines modulate bone turnover. Idiopathic hypercalciuria (IH) seems to be associated with bone mineral loss. Therefore, the aim of this study was to assess cytokines involved in bone turnover in patients with IH. METHODS: Plasma and spot-urine levels of interleukin (IL)-1ß, IL-6, IL-8, tumor necrosis factor alpha (TNF-α), transforming growth factor ß1 (TGF-ß1), and monocyte chemoattractant protein (MCP-1) were measured in 70 children and adolescents with IH and in 37 healthy controls. Patients with IH were subdivided according to their calciuria at the time of sample collection: ≥4 mg/kg/day (persistent IH, n=27) and below 4 mg/kg/day (controlled IH, n=43). Cytokines were determined by enzyme-linked immunoassay. RESULTS: Plasma and urinary concentrations of IL-1ß, IL-6, IL-8, and TNF-α were undetectable in all groups. No differences were found between controlled and persistent hypercalciuria for plasma and urinary levels of MCP-1 and TGF-ß1. On the other hand, MCP-1 levels were significantly higher in both subgroups of IH in comparison to healthy controls. Furthermore, urinary MCP-1 levels of IH patients correlated positively with bone mineral content (p=0.013). CONCLUSION: Although cytokine measurements did not allow the differentiation between persistent and controlled IH, our findings suggest that MCP-1 might play a role in patients with IH.
Asunto(s)
Citocinas/sangre , Citocinas/orina , Hipercalciuria/inmunología , Absorciometría de Fotón , Adolescente , Factores de Edad , Biomarcadores/sangre , Biomarcadores/orina , Densidad Ósea , Remodelación Ósea , Brasil , Calcio/orina , Estudios de Casos y Controles , Quimiocina CCL2/sangre , Quimiocina CCL2/orina , Niño , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Hipercalciuria/sangre , Hipercalciuria/diagnóstico por imagen , Hipercalciuria/orina , Interleucina-1beta/sangre , Interleucina-1beta/orina , Interleucina-6/sangre , Interleucina-6/orina , Interleucina-8/sangre , Interleucina-8/orina , Vértebras Lumbares/diagnóstico por imagen , Masculino , Factor de Crecimiento Transformador beta1/sangre , Factor de Crecimiento Transformador beta1/orina , Factor de Necrosis Tumoral alfa/sangre , Factor de Necrosis Tumoral alfa/orina , Adulto JovenRESUMEN
Bone remodeling is a continuous and dynamic process of skeletal destruction and renewal. A complex regulatory mechanism with the participation of several cytokines precisely defines the role of osteoclasts in the chain of events leading to bone resorption. There are multiple mechanisms underlying the regulation of bone resorption, which can involve increased calcium excretion and decreased bone density in patients with idiopathic hypercalciuria (IH). However, the pathogenesis of bone mass reduction in IH remains uncertain. The purpose of this review is to summarize the recent published evidence on the possible mechanisms by which cytokines could be associated with the pathogenesis of IH.