Background: Adenoma-adenocarcinoma transition is a key feature of colorectal cancer (CRC) occurrence and is closely regulated by tumor-associated macrophages (TAMs) and CD8⁺ T cells. Here, we investigated the effect of the NF-κB activator 1 (Act1) downregulation of macrophages in the adenoma-adenocarcinoma transition. Methods: This study used spontaneous adenoma-developing Apc^Min/+, macrophage-specific Act1-knockdown (anti-Act1), and Apc^Min/+; anti-Act1 (AA) mice. Histological analysis was performed on CRC tissues of patients and mice. CRC patients’ data retrieved from the TCGA dataset were analyzed. Primary cell isolation, co-culture system, RNA-seq, and fluorescence-activated cell sorting (FACS) were used. Results: By TCGA and TISIDB analysis, the downregulation of Act1 expression in tumor tissues of CRC patients negatively correlated with accumulated CD68⁺ macrophages in the tumor. Relative expression of EMT markers in the tumor enriched ACT1^lowCD68⁺ macrophages of CRC patients. AA mice showed adenoma-adenocarcinoma transition, TAMs recruitment, and CD8⁺ T cell infiltration in the tumor. Macrophages depletion in AA mice reversed adenocarcinoma, reduced tumor amounts, and suppressed CD8⁺ T cell infiltration. Besides, macrophage depletion or anti-CD8a effectively inhibited metastatic nodules in the lung metastasis mouse model of anti-Act1 mice. CRC cells induced activation of IL-6/STAT3 and IFN-γ/NF-κB signaling and the expressions of CXCL9/10, IL-6, and PD-L1 in anti-Act1 macrophages. Anti-Act1 macrophages facilitated epithelial-mesenchymal-transition and CRC cells’ migration via CXCL9/10-CXCR3-axis. Furthermore, anti-Act1 macrophages promoted exhaustive PD1⁺ Tim3⁺ CD8⁺ T cell formation. Anti-PD-L1 treatment repressed adenoma-adenocarcinoma transition in AA mice. Silencing STAT3 in anti-Act1 macrophages reduced CXCL9/10 and PD-L1 expression and correspondingly inhibited epithelial-mesenchymal-transition and CRC cells’ migration. Conclusions: Act1 downregulation in macrophages activates STAT3 that promotes adenoma-adenocarcinoma transition via CXCL9/10-CXCR3-axis in CRC cells and PD-1/PD-L1-axis in CD8⁺ T cells.

Ulcerative colitis (UC) is a recurrent intestinal inflammatory disease. Slit2, a secreted protein, interacts with its receptor Robo1 to regulate the differentiation of intestinal stem cells and participate in inflammation and tumor development. However, whether Slit2/Robo1involved in the pathogenesis of UC is not known. We investigated Slit2/Robo1-mediated UC using a dextran sodium sulfate (DSS)-induced model. Eight-week-old male Slit2-Tg (Slit2 transgene) mice, Robo1/2^+/- (Robo1^+/- Robo2^+/-) mice, and their WT littermates were allocated into two groups: (I) control group (n=10), of mice fed a normal diet and tap water and (II) DSS group (n=10), of mice fed a normal diet and drinking water with 2% DSS for 7 days. Colon tissues were collected and analyzed by qPCR, immunohistochemistry, western blot, and immunofluorescence. Slit2-Tg DSS mice showed less body weight loss, less blood in the stool, and less viscous stool compared to those of WT_Slit DSS mice. Robo1/2^+/- DSS mice displayed a heavier degree of blood in the stool and a more apparent viscosity of the stool compared to those of WT_Robo1/2 DSS mice. Slit2 overexpression maintained Lgr5⁺ stem cell proliferation in the crypt after DSS treatment, significantly increased the LC3II/I ratio, and slightly stimulated p62 expression in the crypt compared to those of DSS-induced WT_Slit mice. Robo1/2 partial knockout reduced the number of Lgr5⁺ stem cells, decreased the LC3II/I ratio, and markedly increased p62 expression in the crypt compare to those of DSS-treated WT_Robo1/2 mice. Our findings suggest that Slit2/Robo1 mediates DSS-induced UC probably by activating the autophagy of Lgr5⁺ stem cells.

We have previously demonstrated that ClC-3 chloride channel activity and expression are significantly increased in remodelled cerebral vessels of hypertensive rats. This study aims to examine whether this channel directly regulates cerebrovascular remodelling during hypertension by using ClC-3^−/− mice. After DOCA-salt treatment, medial cross-sectional area, media thickness, and media–lumen ratio of the basilar artery of ClC-3^+/+ mice were significantly increased, accompanied by reduced lumen diameter, indicating apparent vascular remodelling. The vascular ultrastructure of ClC-3^+/+ hypertensive mice by electron microscopy revealed obvious disarray of SMCs and extracellular matrix accumulation. Immunofluorescence analysis showed that fibronectin was overexpressed in ClC-3^+/+ DOCA-salt mice. All of these vascular structure alterations were prevented in ClC-3^−/− mice despite DOCA-salt treatment. However, propranolol, which reduced blood pressure as effectively as ClC-3 deficiency, failed to prevent basilar artery from remodelling. The vascular structure injury in ClC-3^+/+ hypertensive mice was accompanied by significantly increased expression of matrix metalloproteinase (MMP)-2, membrane-type (MT)1-MMP, and tissue inhibitor of metalloproteinase (TIMP)-2, which was inhibited by ClC-3 knockout. Additionally, the increase in transforming growth factor (TGF)-β1 level in serum, as well as phosphorylation of Smad3 at serine 423/425 in basilar artery, induced by DOCA-salt, was markedly prevented in ClC-3^−/− mice. Our findings suggest that ClC-3 deficiency attenuates cerebrovascular remodelling possibly via the suppression of MMPs/TIMP expression and TGF-β1/Smad3 signalling pathway in this hypertension.

Aim: Although studies on lncRNAs in renal fibrosis have focused on target genes and functions of lncRNAs, a comprehensive interaction analysis of lncRNAs is lacking. Materials & methods: Differenti...

Atrial natriuretic peptide (ANP) activity deficiency contributes to salt-sensitive hypertension in humans and mice. However, the role of ileal microbiota in salt sensitivity in ANP deficiency-related cardiac injury has not been investigated yet. This study used ANP^−/− mice to analyze the role of the salt-sensitive ileal microbiome on cardiac injury. ANP^−/− mice showed an increase in blood pressure (BP), the heart weight/body weight (HW/BW) ratio, and cardiac hypertrophy compared with wild-type (WT) mice. ANP deficiency did not impact the histological structure but reduced occludin expression in the ileum. Antibiotics significantly relieved BP and cardiac hypertrophy in ANP^−/− mice. A high-salt diet (HSD) increased BP, the HW/BW ratio, and cardiac hypertrophy/fibrosis in WT and ANP^−/− mice, and an HSD treatment in ANP^−/− mice exacerbated these cardiac parameters. The HSD markedly decreased muscularis layer thickening, villus length, and numbers of Paneth and goblet cells in the ileum of WT and ANP^−/− mice. Furthermore, the HSD increased the level of TLR4 and IL-1β in ANP^−/− mice ileum compared with WT mice. Antibiotics reduced the HW/BW ratio, cardiac hypertrophy/fibrosis, and the level of TLR4 and IL-1β in the ileum, and rescued the muscularis layer thickening, villus length, and numbers of Paneth and goblet cells in the ileum of HSD-ANP^−/− mice. Importantly, ANP deficiency induced the colonization of Burkholderiales bacterium YL45, Lactobacillus johnsonii, and Lactobacillus reuteri in the ileum on the NSD diet, which was only observed in HSD-induced WT mice but not in WT mice on the NSD. Besides, the HSD significantly enhanced the sum of the percentage of the colonization of Burkholderiales bacterium YL45, Lactobacillus johnsonii, and Lactobacillus reuteri in the ileum of ANP^−/− mice. Ileal microbiota transfer (IMT) from ANP^−/− mice to healthy C57BL/6J mice drove Lactobacillus johnsonii and Lactobacillus reuteri colonization in the ileum, which manifested an increase in BP, the HW/BW ratio, cardiac hypertrophy, and ileal pathology compared with IMT from WT mice. The HSD in C57BL/6J mice with IMT from ANP^−/− mice drove the colonization of Burkholderiales bacterium YL45, Lactobacillus johnsonii, and Lactobacillus reuteri in the ileum and further exacerbated the cardiac and ileal pathology. Our results suggest that salt-sensitive ileal microbiota is probably related to ANP deficiency-induced cardiac injury.