Journal: The FASEB Journal

Article Title: Lysophosphatidic Acid Synergizes With 1,25‐Dihydroxyvitamin D to Promote Fibroblast Growth Factor‐23 Synthesis via MAPK Signaling and Induction of the IL12A Gene

doi: 10.1096/fj.202502235R

Figure Lengend Snippet: Stimulation of FGF23 production by LPA and 1,25D and the whole transcriptome analysis of Ocy454 cells. (A) Secreted total FGF23 (cFGF23) concentrations in the culture medium of mouse long bone explants in response to vehicle (VEH), LPA alone, 1,25D alone, or LPA/1,25D after 24 h of stimulation. (B) Serum intact FGF23 (iFGF23) levels following the intraperitoneal LPA injection into the wild‐type and VDR KO littermates. (C) Experiment design for whole transcriptome analysis in Ocy454 cells. (D) Ven diagrams of differentially expressed genes (DEGs) in response to LPA, 1,25D, or LPA/1,25D treatment 2 and 8 h after stimulation. (E) Volcano plots of LPA and 1,25D responsive genes demonstrating LPA and 1,25D act on Ocy454 cells. (F) Expression profile of osteocyte genes in response to LPA, 1,25D, or the LPA/1,25D treatment after 2‐ and 8‐h stimulation. One‐way ANOVA followed by Tukey's (A) or two‐way ANOVA followed by Bonferroni (B) post hoc tests for multiple comparisons. Mean ± SEM, n = 3–4 experiments and n = 7–10 mice/group, respectively. DEGs and adjusted p values obtained by Benjamini‐Hochberg (BH) method using Limma package on R studio (D–F). Blue: 1,25D and Red: LPA responsive genes (E). Asterisks represent * p < 0.05, ** p < 0.01, *** p < 0.001 compared to vehicle‐treated group (F).

Article Snippet: Serum was collected 24 h later, and intact FGF23 (iFGF23) concentrations were measured using the iFGF23 (60–6800, Quidel) kit according to the manufacturer's instructions.

Techniques: Injection, Expressing

Journal: JBMR Plus

Article Title: Multi-tissue spatial transcriptomics identified simultaneous responses to oxidative stress and apoptosis in parallel with tissue-specific reprogramming in modeled chronic kidney disease-mineral and bone disorder

doi: 10.1093/jbmrpl/ziaf161

Figure Lengend Snippet: Spatial transcriptomics identified tissue subtypes in muscle and bone. (A-C) Plasma intact FGF23 and serum TNF and blood urea nitrogen (BUN) levels in control (Ctrl) and CKD-MBD (CKD) mice (* p < .05; ** p < .01; *** p < .001 vs controls). H&E bone-muscle cross-sections for Ctrl (D) and CKD (E) and the Seurat clusters mapped on the sections (F and G). (H) Tissue and fiber type specific marker gene expression. (I) UMAP of Ctrl and CKD samples, with major tissue and muscle fiber types labeled. (J) Localization of major muscle fiber types in Ctrl and CKD tissue sections (colors correspond to UMAP in H).

Article Snippet: Plasma FGF23 was assessed using a rodent specific commercial ELISA for bioactive, intact FGF23 (“iFGF23”; Quidel, Inc.).

Techniques: Clinical Proteomics, Control, Marker, Gene Expression, Labeling

Journal: Cell Communication and Signaling : CCS

Article Title: The Roxadustat (FG-4592) ameliorates tubulointerstitial fibrosis by promoting intact FGF23 cleavage

doi: 10.1186/s12964-025-02175-2

Figure Lengend Snippet: FG-4592 lowers iFGF23 level in CKD rats and CKD patients. Parameters measured include ( A ) Serum intact fibroblast growth factor 23 (iFGF23) levels in CKD rats. B Serum total FGF23 levels in CKD rats. C Serum iFGF23 levels in CKD patients. D Serum total FGF23 levels in CKD patients. E Scatter plots with linear regression analysis demonstrating a significant correlation between blood urea nitrogen (BUN) and iFGF23 levels in CKD rats. F Scatter plots with linear regression analysis showing a significant correlation between Scr and iFGF23 levels in CKD rats. G Scatter plots with linear regression analysis revealing a significant correlation between iFGF23 levels and the percentage of fibrotic area in the kidney of CKD rats. H Scatter plots with linear regression analysis indicating a significant correlation between iFGF23 levels and Collagen 1 staining intensity in the kidney of CKD rats. I Scatter plots with linear regression analysis illustrating a significant correlation between iFGF23 levels and Fibronectin staining intensity in the kidney of CKD rats. J Scatter plots with linear regression analysis demonstrating a significant correlation between iFGF23 levels and α-SMA staining intensity in the kidney of CKD rats. Data are presented as means ± SD ( n = 5). Statistical significance is denoted as follows: * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001

Article Snippet: The iFGF23 concentration was examined on plasma collected from rats under fed conditions using ELISA assays specific for rat iFGF23 (Quidel, cat#: 60–6800). iFGF23 and cFGF23 concentration were examined on plasma collected from rats under fed conditions using ELISA assays specific for rat total FGF23 (Quidel, cat#: 60–6300). iFGF23 and cFGF23 concentration were examined on plasma collected from CKD patients under fed conditions using ELISA assays specific for human iFGF23 or total FGF23 (Quidel, cat#: 60–6600 and cat#: 60–6100). iFGF23 ELISAs detect full-length, biologically active FGF23 that can exert phosphaturia, whereas total FGF23 ELISAs detect both iFGF23 and its C-terminal fragments and therefore provide a measure of the total amount of circulating plasma FGF23.

Techniques: Staining

Journal: Cell Communication and Signaling : CCS

Article Title: The Roxadustat (FG-4592) ameliorates tubulointerstitial fibrosis by promoting intact FGF23 cleavage

doi: 10.1186/s12964-025-02175-2

Figure Lengend Snippet: iFGF23 mediates FG-4592-induced inhibition of tubular cell fibrogenesis. HK-2 cells were pre-treated with TGF-β1 (10 ng/mL) for 24 h, followed by treatment with recombinant FGF23 (rFGF23, 50 ng/mL) or vehicle for an additional 24 h. Parameters measured include: A COL1A1 mRNA expression levels in HK-2 cells, as determined by quantitative PCR (qPCR). B TGFB1 mRNA expression levels in HK-2 cells, as determined by qPCR. C Collagen 1 protein expression levels in HK-2 cells, as assessed by Western blot analysis. D Schematic illustration of the co-culture system using UMR-106 cells and HK-2 cells in a Transwell setup. E mRNA expression levels of Fn1 , Acta2 , and Col1a1 in HK-2 cells, as quantified by qPCR. Data are presented as means ± SD ( n = 5). Statistical significance is denoted as follows: *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001

Article Snippet: The iFGF23 concentration was examined on plasma collected from rats under fed conditions using ELISA assays specific for rat iFGF23 (Quidel, cat#: 60–6800). iFGF23 and cFGF23 concentration were examined on plasma collected from rats under fed conditions using ELISA assays specific for rat total FGF23 (Quidel, cat#: 60–6300). iFGF23 and cFGF23 concentration were examined on plasma collected from CKD patients under fed conditions using ELISA assays specific for human iFGF23 or total FGF23 (Quidel, cat#: 60–6600 and cat#: 60–6100). iFGF23 ELISAs detect full-length, biologically active FGF23 that can exert phosphaturia, whereas total FGF23 ELISAs detect both iFGF23 and its C-terminal fragments and therefore provide a measure of the total amount of circulating plasma FGF23.

Techniques: Inhibition, Recombinant, Expressing, Real-time Polymerase Chain Reaction, Western Blot, Co-Culture Assay

Journal: Cell Communication and Signaling : CCS

Article Title: The Roxadustat (FG-4592) ameliorates tubulointerstitial fibrosis by promoting intact FGF23 cleavage

doi: 10.1186/s12964-025-02175-2

Figure Lengend Snippet: FG-4592 ameliorates TIF by inhibiting iFGF23-WNT5A pathway. Parameters measured include ( A ) Hierarchical clustering analysis revealing distinct mRNA expression profiles among the experimental groups. Yellow and blue shades indicate expression levels above and below the relative mean, respectively, across all samples. B Gene Ontology (GO) enrichment analysis. C Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. D and F mRNA and protein expression levels of Wnt5a and β-catenin in the following groups: sham, CKD + vehicle, and CKD + FG-4592. E and G mRNA and protein expression levels of Wnt5a and β-catenin in the following groups: CKD + FG-4592 + vehicle and CKD + FG-4592 + rFGF23. H and I Representative immunohistochemical images showing Wnt5a and β-catenin expression in kidney tissues across different experimental groups. J mRNA expression levels of COL1A1 , ACTA1 , WNT5A , and CTNNB1 in HK-2 cells following WNT5A siRNA interference, as determined by quantitative PCR (qPCR). K Protein expression levels of Collagen 1, Wnt5a, and β-catenin in HK-2 cells after WNT5A siRNA interference, as assessed by Western blot analysis. Scale bars: 50 μm. Data are presented as means ± SD ( n = 5). Statistical significance is denoted as follows: * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001

Article Snippet: The iFGF23 concentration was examined on plasma collected from rats under fed conditions using ELISA assays specific for rat iFGF23 (Quidel, cat#: 60–6800). iFGF23 and cFGF23 concentration were examined on plasma collected from rats under fed conditions using ELISA assays specific for rat total FGF23 (Quidel, cat#: 60–6300). iFGF23 and cFGF23 concentration were examined on plasma collected from CKD patients under fed conditions using ELISA assays specific for human iFGF23 or total FGF23 (Quidel, cat#: 60–6600 and cat#: 60–6100). iFGF23 ELISAs detect full-length, biologically active FGF23 that can exert phosphaturia, whereas total FGF23 ELISAs detect both iFGF23 and its C-terminal fragments and therefore provide a measure of the total amount of circulating plasma FGF23.

Techniques: Expressing, Immunohistochemical staining, Real-time Polymerase Chain Reaction, Western Blot

Journal: Cell Communication and Signaling : CCS

Article Title: The Roxadustat (FG-4592) ameliorates tubulointerstitial fibrosis by promoting intact FGF23 cleavage

doi: 10.1186/s12964-025-02175-2

Figure Lengend Snippet: FG-4592 lowers iFGF23 levels through Furin-mediated cleavage. Parameters measured include ( A ) mRNA expression levels of Furin , Galnt3 , and Fam20c in bone tissues from the following groups: sham, CKD + vehicle, and CKD + FG-4592, as determined by quantitative PCR (qPCR). B Protein levels of HIF-1α, Furin, and intact fibroblast growth factor 23 (iFGF23) in bone tissues treated with FG-4592 or vehicle, as assessed by Western blot analysis. C Representative images of hematoxylin and eosin (HE) staining of bone tissues (scale bars: 20 μm), along with IHC staining for HIF-1α and iFGF23 (scale bars: 50 μm) and Furin (scale bars: 100 μm). D UMR-106 cells were pretreated with 10 nM 1,25(OH) 2 D 3 , and the expression of FGF23 mRNA was analyzed using real-time PCR. E Western blot analysis was performed to measure iFGF23 protein expression in UMR-106 cells. Cells were pretreated with indoxyl sulfate (IS, 0.5 mM) or vehicle, followed by treatment with FG-4592 (50 μM) or vehicle for 24 h. F Levels of iFGF23 and total FGF23 in the cell supernatant were quantified using an ELISA assay kit. G Western blot analysis was used to evaluate the protein expression of iFGF23 and Furin in UMR-106 cells. H Motif map of the Furin promoter region, highlighting the HIF-1 binding site. I ChIP assays demonstrated HIF-1 binding to the Furin promoter, which was enhanced by FG-4592 stimulation (50 μM for 24 h). J Protein expression levels of Furin and iFGF23 in UMR-106 cells following Furin siRNA interference, as determined by Western blot analysis. K Levels of iFGF23 and total FGF23 in the cell supernatant were measured using an ELISA assay kit after Furin siRNA interference. Data are presented as means ± SD ( n = 5). Statistical significance is denoted as follows: * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001

Article Snippet: The iFGF23 concentration was examined on plasma collected from rats under fed conditions using ELISA assays specific for rat iFGF23 (Quidel, cat#: 60–6800). iFGF23 and cFGF23 concentration were examined on plasma collected from rats under fed conditions using ELISA assays specific for rat total FGF23 (Quidel, cat#: 60–6300). iFGF23 and cFGF23 concentration were examined on plasma collected from CKD patients under fed conditions using ELISA assays specific for human iFGF23 or total FGF23 (Quidel, cat#: 60–6600 and cat#: 60–6100). iFGF23 ELISAs detect full-length, biologically active FGF23 that can exert phosphaturia, whereas total FGF23 ELISAs detect both iFGF23 and its C-terminal fragments and therefore provide a measure of the total amount of circulating plasma FGF23.

Techniques: Expressing, Real-time Polymerase Chain Reaction, Western Blot, Staining, Immunohistochemistry, Enzyme-linked Immunosorbent Assay, Binding Assay

Journal: Cell Communication and Signaling : CCS

Article Title: The Roxadustat (FG-4592) ameliorates tubulointerstitial fibrosis by promoting intact FGF23 cleavage

doi: 10.1186/s12964-025-02175-2

Figure Lengend Snippet: Schematic illustration of FG-4592 ameliorating TIF. During CKD, FG-4592 transcriptionally upregulates Furin expression, which subsequently cleaves iFGF23, leading to a reduction in iFGF23 levels and amelioration of TIF

Article Snippet: The iFGF23 concentration was examined on plasma collected from rats under fed conditions using ELISA assays specific for rat iFGF23 (Quidel, cat#: 60–6800). iFGF23 and cFGF23 concentration were examined on plasma collected from rats under fed conditions using ELISA assays specific for rat total FGF23 (Quidel, cat#: 60–6300). iFGF23 and cFGF23 concentration were examined on plasma collected from CKD patients under fed conditions using ELISA assays specific for human iFGF23 or total FGF23 (Quidel, cat#: 60–6600 and cat#: 60–6100). iFGF23 ELISAs detect full-length, biologically active FGF23 that can exert phosphaturia, whereas total FGF23 ELISAs detect both iFGF23 and its C-terminal fragments and therefore provide a measure of the total amount of circulating plasma FGF23.

Techniques: Expressing