RESUMO
A cDNA clone encoding 8 kDa protein was retrieved from an EST pool of Chinese liver fluke Clonorchis sinensis. A deduced polypeptide of the cDNA clone was similar to 8 kDa Ca(2+)-binding proteins from other parasitic trematodes, and, thus, named as CsCa8, containing two EF-hand Ca(2+)-binding sites. Homology models predicted CsCa8 to be a single globular structure having four helices and molecular folds similar to Ca(2+)-binding state of other small Ca(2+)-binding proteins. Recombinant CsCa8 protein showed specific Ca(2+)-binding affinity and shifting in native gel mobility assay. Mouse immune sera raised against recombinant CsCa8 protein recognized native CsCa8 from adult C. sinensis worm extract. CsCa8 was localized in oral and ventral suckers, vitelline follicles and subtegumental tissues. These findings suggest that CsCa8 might be involved in cellular Ca(2+) signal transduction for muscle contraction and egg production.
Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Clonorchis sinensis/genética , Motivos EF Hand , Proteínas de Helminto/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Ligação ao Cálcio/genética , Clonorchis sinensis/metabolismo , DNA Complementar/genética , Proteínas de Helminto/genética , Soros Imunes , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de AminoácidosRESUMO
Radiation induced fibrosis of the skin is a late toxicity that may result in loss of function due to reduced range of motion and pain. The current study sought to determine if oral delivery of quercetin mitigates radiation-induced cutaneous injury. Female C3H/HeN mice were fed control chow or quercetin-formulated chow (1% by weight). The right hind leg was exposed to 35 Gy of X rays and the mice were followed serially to assess acute toxicity and hind leg extension. Tissue samples were collected for assessment of soluble collagen and tissue cytokines. Human and murine fibroblasts were subjected to clonogenic assays to determine the effects of quercetin on radiation response. Contractility of fibroblasts was assessed with a collagen contraction assay in the presence or absence of quercetin and transforming growth factor-ß (TGF-ß). Western blotting of proteins involved in fibroblast contractility and TGF-ß signaling were performed. Quercetin treatment significantly reduced hind limb contracture, collagen accumulation and expression of TGF-ß in irradiated skin. Quercetin had no effect on the radioresponse of fibroblasts or murine tumors, but was capable of reducing the contractility of fibroblasts in response to TGF-ß, an effect that correlated with partial stabilization of phosphorylated cofilin. Quercetin is capable of mitigating radiation induced skin fibrosis and should be further explored as a therapy for radiation fibrosis.