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Autosomal dominant polycystic kidney disease (ADPKD) is a monogenetic disease that still lacks effective therapy. Repulsive guidance molecule b (RGMb), a co-receptor for bone morphogenetic proteins (BMPs) and a ligand for neogenin, is expressed in renal tubular epithelial cells. Previous studies showed that RGMb plays negative roles in several types of tumors and prevents the immune system from over activation. The present study was designed to explore the effects of RGMb in ADPKD development. We found that expression of RGMb in kidney was less in PKD mice than wild-type mice. With stimulation of 8-bromo-cAMP, RGMb-null embryonic kidneys had greater cyst index, though their ureteric bud branched less than wild-type mice at E13.5. Postnatal RGMb-null kidneys showed interstitial hyperplasia and decreased tubular structures, especially in the boundary area of renal cortex and medulla. RGMb overexpression dramatically inhibited cyst development and promoted tubulogenesis in MDCK cells grown in 3D collagen gels. Biochemical analysis showed increased p-Smad1/5/8 and decreased p-ERK in RGMb-overexpressing MDCK cells, suggesting modulated BMP signaling. Specific inhibition of p-Smad1/5/8 by LDN193189 reversed the suppression of RGMb on MDCK cyst model. These results reveal RGMb as a novel regulator for ADPKD by promoting renal tubule branching and regulating BMP signaling pathway. Elevating RGMb and enhancing p-Smad1/5/8 are promising new strategies to treat ADPKD. [ABSTRACT FROM AUTHOR]

Previous studies have found that Yang-Xin-Shu-Mai granule (YXSMG) has certain advantages in the treatment of stable coronary heart disease. However, YXSMG can inhibit the progression of atherosclerotic plaque and stabilize vulnerable plaque needs to be further explored and studied. This research, mass spectrometry analysis, network pharmacology, in vivo and in vitro experimental studies were conducted to explore the mechanism of YXSMG on atherosclerosis. To decipher the mechanism of atherosclerotic plaque, stabilization for YXSMG by analysis of its active ingredients and biological network and activity in whole animal and at cellular and molecular levels. The active components of YXSMG were determined using high performance liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS) analysis. The 'Disease-Compound-Target-Pathway' network diagram was constructed using network pharmacology, and the stability of binding between core targets and core compounds was analyzed with molecular docking. After intervention with YXSMG, the pathology of aortic plaque, inflammation in the surrounding tissue, expression of TLR9/MyD88/NF-κB pathway protein in plaque and M1/M2 polarization of plaque macrophages were evaluated in vivo in apolipoprotein E-deficient (ApoE−/−) mice fed with high-fat diet. To verify whether it suppressed inflammation by inhibiting Toll-like receptor 9 (TLR9) reprogramming of macrophage polarization, we used RAW264.7 macrophages treated with specific TLR9 agonist (ODN1826) and inhibitor (ODN2088). Five active compounds were identified in YXSMG: catechin, formononetin, tanshinone IIA, cryptotanshinone and glycitein. Network pharmacology studies revealed TLR9 as one of the core targets of YXSMG intervention in atherosclerosis. Computer simulation of molecular docking showed that TLR9 could interact with the core compound to form a stable complex. In vivo experiments confirmed that YXSMG could significantly inhibit atherosclerotic plaque, reduce levels of blood lipids and inflammatory factors, downregulate TLR9/MyD88/NF-κB pathway protein and inhibit aortic sinus macrophages polarization to M1, but promote their polarization to M2 to inhibit inflammation. In vitro experiments revealed that YXSMG could downregulate expression of TLR9 gene and protein in ODN1826-activated RAW264.7 macrophages. ODN2088 had a synergistic effect with YXSMG on the TLR9/MyD88/NF-κB signaling pathway, and reprogrammed macrophages polarization from M1 to M2 by inhibiting TLR9, thus reducing immuno-inflammatory response. YXSMG can reduce the level of blood lipid and improve the size of atherosclerotic plaque and inflammatory infiltration in ApoE−/− mice fed with high fat. It is concluded that YXSMG can improve the mechanism of atherosclerotic plaque by inhibiting TLR9/MyD88/NF-κB pathway reprogramming macrophage M1/M2 polarization and reducing arterial inflammation. The mechanism of YXSMG in the treatment of atherosclerosis. TLR9: toll like receptor 9; MyD88: myeloid differentiation primary response 88; IKKα: IκB kinase α; IKKβ: IκB kinase β; NF-κB: Nuclear factor kappa B; IL-10: Interleukin-10; Arg1: arginase 1; IL-6: Interleukin-6; IL-1β: Interleukin-1β; TNF-α: Tumor necrosis factor-alpha. [Display omitted] [ABSTRACT FROM AUTHOR]

Background Hypertrophic scars and keloids, characterized by over-proliferation of fibroblasts and aberrant formation of the extracellular matrix (ECM), are considered fibrotic diseases. Accumulating evidence indicates that mesenchymal stem cells (MSCs) promote scar-free wound healing and inhibit fibrotic tissue formation, making them a potentially effective therapeutic treatment for hypertrophic scars and keloids. Objective To investigate the paracrine effects of bone marrow derived MSCs (BMSCs) on the biological behavior of hypertrophic scar fibroblasts (HSFs) and keloid fibroblasts (KFs). Methods Proliferative and profibrotic phenotype changes of the fibroblasts were analyzed by immunofluorescence staining, in-cell western blot, and real-time PCR. Results BMSC-conditioned medium inhibited HSF and KF proliferation and migration, but did not induce apoptosis. Interestingly, normal skin fibroblast-conditioned medium exhibited no inhibitory effects on HSF or KF proliferation and migration. Furthermore, BMSC-conditioned medium significantly decreased expression of profibrotic genes, including connective tissue growth factor, plasminogen activator inhibitor-1, transforming growth factor-β 1 , and transforming growth factor-β 2 , in HSFs and KFs at both transcriptional and translational levels. In contrast, the expression of antifibrotic genes, such as transforming growth factor-β 3 and decorin, was substantially enhanced under the same culture conditions. Finally, we observed that BMSC-conditioned medium suppressed the ECM synthesis in HSFs and KFs, as indicated by decreased expression of collagen I and fibronectin and low levels of hydroxyproline in cell culture supernatant. Conclusion These findings suggest that BMSCs attenuate the proliferative and profibrotic phenotype associated with HSFs and KFs and inhibit ECM synthesis through a paracrine signaling mechanism. [ABSTRACT FROM AUTHOR]