Project description:Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized as progressive and irreversible fibrosis in the interstitium of lung tissues. There is still an unmet need to develop a novel therapeutic drug for IPF. We have previously demonstrated that periostin, a matricellular protein, plays an important role in the pathogenesis of pulmonary fibrosis. However, the underlying mechanism of how periostin causes pulmonary fibrosis remains unclear. In this study, we sought to see whether the cross-talk between transforming growth factor-b (TGF-b), a central mediator in the pathogenesis of pulmonary fibrosis, and periostin in lung fibroblasts leads to generation of pulmonary fibrosis and whether taking advantage of the cross-talk between TGF-b and periostin, inhibitors for integrin aVb3, a periostin receptor, can block pulmonary fibrosis in the model mice. We found that there exists a cross-talk between TGF-b and periostin signals via aVb3/b5 converging into Smad3. This cross-talk is important for expression of several downstream molecules of TGF-b including serpin family E member 1, CCN family member 2/connective tissue growth factor, insulin-like growth factor binding protein-3, and IL-11, all of which have been already shown to be important for pulmonary fibrosis. We, moreover, found several potent integrin inhibitors to block the cross-talking with TGF-b signals and CP4715, one of the compounds, improved bleomycin-induced pulmonary fibrosis in mice. These results suggest that the cross-talk between TGF-b and periostin can be targeted for pulmonary fibrosis and that CP4715 can be a potential therapeutic agent to block the cross-talk between TGF-b and periostin.
Project description:Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized as progressive and irreversible fibrosis in the interstitium of lung tissues. There is still an unmet need to develop a novel therapeutic drug for IPF. We have previously demonstrated that periostin, a matricellular protein, plays an important role in the pathogenesis of pulmonary fibrosis. However, the underlying mechanism of how periostin causes pulmonary fibrosis remains unclear. In this study, we sought to see whether the cross-talk between transforming growth factor-b (TGF-b), a central mediator in the pathogenesis of pulmonary fibrosis, and periostin in lung fibroblasts leads to generation of pulmonary fibrosis and whether taking advantage of the cross-talk between TGF-b and periostin, inhibitors for integrin aVb3, a periostin receptor, can block pulmonary fibrosis in the model mice. We found that there exists a cross-talk between TGF-b and periostin signals via aVb3/b5 converging into Smad3. This cross-talk is important for expression of several downstream molecules of TGF-b including serpin family E member 1, CCN family member 2/connective tissue growth factor, insulin-like growth factor binding protein-3, and IL-11, all of which have been already shown to be important for pulmonary fibrosis. We, moreover, found several potent integrin inhibitors to block the cross-talking with TGF-b signals and CP4715, one of the compounds, improved bleomycin-induced pulmonary fibrosis in mice. These results suggest that the cross-talk between TGF-b and periostin can be targeted for pulmonary fibrosis and that CP4715 can be a potential therapeutic agent to block the cross-talk between TGF-b and periostin.
Project description:The aim of this study was to identify miRNAs that regulate AKI and develop their applications as diagnostic biomarkers and therapeutic agents. First, kidney tissues from two different AKI mouse models, namely, AKI induced by the administration of lipopolysaccharide (LPS) causing sepsis (LPS-AKI mice) and AKI induced by renal ischemia–reperfusion injury (IRI-AKI mice), were exhaustively screened for their changes of miRNA expression compared with that of control mice by microarray analysis.
Project description:We performed Drop-seq using dissociated total kidney cells to identify cell types, gene expression patterns and signaling pathways in mouse kidneys after IRI.
Project description:Single cell sequencing studies have characterized the transcriptomic signature of cell types within the kidney. However, the spatial distribution of acute kidney injury (AKI) is regional and affects cells heterogeneously. We first optimized coordination of spatial transcriptomics and single nuclear sequencing datasets, mapping 30 dominant cell types to a human nephrectomy. The predicted cell type spots corresponded with the underlying histopathology. To study the implications of AKI on transcript expression, we then characterized the spatial transcriptomic signature of two murine AKI models: ischemia reperfusion injury (IRI) and cecal ligation puncture (CLP). Localized regions of reduced overall expression were associated with injury pathways. Using single cell sequencing, we deconvoluted the signature of each spatial transcriptomic spot, identifying patterns of colocalization between immune and epithelial cells. Neutrophils infiltrated the renal medulla in the ischemia model. Atf3 was identified as a chemotactic factor in S3 proximal tubules. In the CLP model, infiltrating macrophages dominated the outer cortical signature and Mdk was identified as a corresponding chemotactic factor. The regional distribution of these immune cells was validated with multiplexed CO-Detection by inDEXing (CODEX) immunofluorescence. Spatial transcriptomic sequencing complements single cell sequencing by uncovering mechanisms driving immune cell infiltration and detection of relevant cell subpopulations.
Project description:Ischemia reperfusion injury (IRI) in organ transplantation remains a significant problem with limited alternative therapeutic options. Organs that undergo significant damage during IRI, particularly those enduring long warm ischemia times, undergo significant delayed graft function (DGF) after reperfusion and tend to have greater complications long term with the onset of chronic rejection. The gas molecule carbon monoxide (CO) has emerged as an agent that can suppress IRI in rodent models of solid organ transplantation. Since the use of CO is a potential therapeutic modality in humans, we tested if CO can prevent DGF in a pig model of kidney transplantation Keywords: stress response, treatment response 18 Samples from pig kidneys, two naïve controls, two timepoints, two conditions, 4 replicates
Project description:Incomplete repair after acute kidney injury (AKI) is associated with progressive loss of tubular cell function and development of chronic kidney disease (CKD). Here, we compared the kidney single-cell transcriptomes from the mice subjected to either unilateral ischemia-reperfusion kidney injury with contralateral nephrectomy (IRI/CL-NX, in which tubule repair predominates) or unilateral IRI with contralateral kidney intact (U-IRI, in which fibrosis and atrophy predominates) to investigate the mechanism(s) underlying transition to CKD following AKI.
Project description:Orthologous proteins often harbor numerous substitutions, but whether these differences result from neutral or adaptive processes is usually unclear. To tackle this challenge, we examined the divergent evolution of a model bacterial signaling pathway comprising the kinase PhoR and its cognate substrate PhoB. We show that the specificity-determining residues of these proteins are typically under purifying selection, but have, in α-proteobacteria, undergone a burst of diversification followed by extended stasis. By reversing mutations that accumulated in an α-proteobacterial PhoR, we demonstrate that these substitutions were adaptive, enabling PhoR to avoid cross-talk with a paralogous pathway that arose specifically in α-proteobacteria. Our findings demonstrate that duplication and the subsequent need to avoid cross-talk strongly influence signaling protein evolution. These results provide a concrete example of how system-wide insulation can be achieved post-duplication through a surprisingly limited number of mutations. Our work may help explain the apparent ease with which paralogous protein families expanded in all organisms. Two-condition experiment, mutant vs. WT in given growth media
Project description:To identify the direct m6A demethylation targets of ALKBH5 at the onset of renal IRI, we performed methylated RNA immunoprecipitation sequencing (MeRIP-seq) and RNA sequencing (RNA-seq) using RNA isolated from IRI mouse kidney of WT and KO mice 24h after I/R (WT n=3 vs. KO n=3)