Unconjugated
Cardiac fibrosis is a fundamental constituent of a variety of cardiac dysfunction, making it a leading cause of death worldwide. However, no effective treatment for cardiac fibrosis is available. Therefore, novel therapeutics for cardiac fibrosis are highly needed. Recently, miR-19b has been found to be able to protect hydrogen peroxide (H2 O2 )-induced apoptosis and improve cell survival in H9C2 cardiomyocytes, while down-regulation of miR-19b had opposite effects, indicating that increasing miR-19b may be a new therapeutic strategy for attenuating cellular apoptosis during myocardial ischaemia-reperfusion injury. However, considering the fact that microRNAs might exert a cell-specific role, it is highly interesting to determine the role of miR-19b in cardiac fibroblasts. Here, we found that miR-19b was able to promote cardiac fibroblast proliferation and migration. However, miR-19b mimics and inhibitors did not modulate the expression level of collagen I. Pten was identified as a target gene of miR-19b, which was responsible for the effect of miR-19b in controlling cardiac fibroblast proliferation and migration. Our data suggest that the role of miR-19b is cell specific, and systemic miR-19b targeting in cardiac remodelling might be problematic. Therefore, it is highly needed and also urgent to investigate the role of miR-19b in cardiac remodelling in vivo.
Early-stage hepatic granuloma and advanced-stage fibrosis are important characteristics of schistosomiasis. The direct consequences of gadolinium chloride (GdCl3) in egg-induced granuloma formation have not been reported, although GdCl3 is known to block the macrophages. In present study, mice were infected with 15 Schistosoma japonicum (S. japonicum) cercariae and treated with GdCl3 (10 mg/kg body weight) twice weekly from day 21 to day 42 post-infection during the onset of egg-laying towards early granuloma formation. Histochemical staining showed that repeated injection of GdCl3 decreased macrophages infiltration in liver of mice infected with S. japonicum. Macrophage depletion by GdCl3 during the initial phase attenuated liver pathological injury characterized by smaller granuloma size and decreased immune inflammation as well as less fibrogenesis. In addition, IL-13Rα2 expression was reduced by GdCl3 in liver of mice infected with S. japonicum. The results suggest that GdCl3 depleted macrophages, which attenuated helminth infected immune responses involving with IL-13Rα2 signal. These findings would highlight a therapeutic potential via manipulating IL-13Rα2+ macrophage in schistosomiasis.