The flavonoid fisetin ameliorates renal fibrosis by inhibiting SMAD3 phosphorylation, oxidative damage, and inflammation in ureteral obstructed kidney in mice

Background Renal fibrosis is characterized by the accumulation of extracellular matrix and inflammatory cells and kidney dysfunction, which is a major pathway in the progression of chronic kidney disease (CKD). Accumulating evidence indicates that oxidative stress plays a critical role in the initiation and progression of CKD via proinflammatory and profibrotic signaling pathways. Fisetin (3,3′,4′,7-tetrahydroxyflavone) has biological activities including antioxidant, anti-inflammatory, and anti-aging effects. Therefore, we evaluated the antifibrotic effects of fisetin on unilateral ureteral obstruction (UUO)-induced kidneys. Methods C57BL/6 female mice were subjected to right UUO and intraperitoneally injected every other day with fisetin (25 mg/kg/day) or vehicle from 1 hour before surgery to 7 days after surgery. Kidney samples were analyzed for renal fibrosis (α-smooth muscle actin [α-SMA] expression, collagen deposition, and transforming growth factor [TGF] β1/SMAD3 signaling pathway), oxidative damage (4-HNE and 8-OHdG expression), inflammation (proinflammatory cytokine/chemokine, macrophage, and neutrophil infiltration), and apoptosis (TUNEL staining). Cultured human proximal tubule cells were treated with fisetin before TGF-β to confirm the TGF-β downstream pathway (SMAD2/3 phosphorylation). Results We found that fisetin treatment protected against renal fibrosis by inhibiting the phosphorylation of SMAD3, oxidative damage, inflammation, apoptotic cell death, and accumulation of profibrotic M2 macrophages in the obstructed kidneys. In cultured human proximal tubular cells, fisetin treatment inhibited TGF-β1–induced phosphorylation of SMAD3 and SMAD2. Conclusion Fisetin alleviates kidney fibrosis to protect against UUO-induced renal fibrosis, and could be a novel therapeutic drug for obstructive nephropathy

MicroRNA-150 modulates intracellular Ca2+ levels in naïve CD8+ T cells by targeting TMEM20

Regulation of intracellular Ca2+ signaling is a major determinant of CD8+ T cell responsiveness, but the mechanisms underlying this regulation of Ca2+ levels, especially in naïve CD8+ T cells, are not fully defined. Here, we showed that microRNA-150 (miR-150) controls intracellular Ca2+ levels in naïve CD8+ T cells required for activation by suppressing TMEM20, a negative regulator of Ca2+ extrusion. miR-150 deficiency increased TMEM20 expression, which resulted in increased intracellular Ca2+ levels in naïve CD8+ T cells. The subsequent increase in Ca2+ levels induced expression of anergy-inducing genes, such as Cbl-b, Egr2, and p27, through activation of NFAT1, as well as reduced cell proliferation, cytokine production, and the antitumor activity of CD8+ T cells upon antigenic stimulation. The anergy-promoting molecular milieu and function induced by miR-150 deficiency were rescued by reinstatement of miR-150. Additionally, knockdown of TMEM20 in miR-150-deficient naïve CD8+ T cells reduced intracellular Ca2+ levels. Our findings revealed that miR-150 play essential roles in controlling intracellular Ca2+ level and activation in naïve CD8+ T cells, which suggest a mechanism to overcome anergy induction by the regulation of intracellular Ca2+ levels115Ysciescopu

Hepatitis C Virus Core Protein Inhibits Interleukin 12 and Nitric Oxide Production from Activated Macrophages

AbstractA characteristic feature of hepatitis C virus (HCV) infection is a high frequency of persistence and the progression to chronic liver diseases. Recent data suggest that prevalent T helper (Th) 2 immunity as well as weak HCV-specific T-cell response is associated with viral persistence. Here, we showed that the production of interleukin 12 (IL-12) and nitric oxide (NO) that is critical for the induction of Th1 and innate immunity, but not that of tumor necrosis factor α (TNF-α), was significantly suppressed in both HCV core-expressing macrophage cell lines and mouse peritoneal macrophages treated with recombinant core protein. In addition, IL-12 p40 promoter activity was repressed by the presence of HCV core in macrophages stimulated with lipopolysaccharride (LPS) following IFN-γ treatment, indicating that IL-12 production may be downregulated at the transcriptional level. We also found that proliferation of T cells and IFN-γ production in mixed lymphocyte reactions (MLR) with core-expressing cells were inhibited. Taken together, our results suggest that HCV core protein could play roles in suppressing the induction of Th1 immunity through inhibition of IL-12 and NO production

Co-Immunization of Plasmid DNA Encoding IL-12 and IL-18 with Bacillus Calmette-Guérin Vaccine against Progressive Tuberculosis

∙ The authors have no financial conflicts of interest. Purpose: Bacillus Calmette-Guérin (BCG) vaccine has widely been used to immunize against tuberculosis, but its protective efficacy is variable in adult pulmonary tuberculosis, while it is not efficiently protective against progressive infection of virulent Mycobacterium tuberculosis strains. In this study, the protective effects of plasmid DNA vaccine constructs encoding IL-12 or IL-18 with the BCG vaccine were evaluated against progressive infection of M. tuberculosis, using mouse aerosol challenge model. Materials and Methods: Plasmid DNA vaccine constructs encoding IL-12 or IL-18 were constructed and mice were immunized with the BCG vaccine or with IL-12 DNA or IL-18 DNA vaccine constructs together with the BCG vaccine. Results: The BCG vaccine induced high level of interferon gamma (IFN-γ) but co-immunization of IL-12 or IL-18 DNA vaccine constructs with the BCG vaccine induced significantly higher level of IFN-γ than a single BCG vaccine. The BCG vaccine was highly protective at early stage of M. tuberculosi

A Case of Malignant Pericardial Mesothelioma With Constrictive Pericarditis Physiology Misdiagnosed as Pericardial Metastatic Cancer

Malignant pericardial mesothelioma is a rare and progressive cardiac tumor. There is no established standard treatment and the prognosis is poor. Most patients were retrospectively diagnosed from surgery or autopsy due to absence of specific clinical manifestation. Most patients with pericardial mesothelioma have demonstrated constrictive physiology on echocardiography or cardiac catheterization. Therefore, pericardial mesothelioma was often misdiagnosed as other causes of constrictive pericarditis. We report a case of primary pericardial mesothelioma misdiagnosed as pericardial metastasis of unknown origin