Genome-wide association studies have discovered a link between genetic variants on human chromosome 15q26.1 and increased coronary artery disease (CAD) susceptibility; however, the underlying ...pathobiological mechanism is unclear. This genetic locus contains the
(FES proto-oncogene, tyrosine kinase) gene encoding a cytoplasmic protein-tyrosine kinase involved in the regulation of cell behavior. We investigated the effect of the 15q26.1 variants on FES expression and whether FES plays a role in atherosclerosis.
Analyses of isogenic monocytic cell lines generated by CRISPR (clustered regularly interspaced short palindromic repeats)-mediated genome editing showed that monocytes with an engineered 15q26.1 CAD risk genotype had reduced FES expression. Small-interfering-RNA-mediated knockdown of FES promoted migration of monocytes and vascular smooth muscle cells. A phosphoproteomics analysis showed that FES knockdown altered phosphorylation of a number of proteins known to regulate cell migration. Single-cell RNA-sequencing revealed that in human atherosclerotic plaques, cells that expressed
were predominately monocytes/macrophages, although several other cell types including smooth muscle cells also expressed
. There was an association between the 15q26.1 CAD risk genotype and greater numbers of monocytes/macrophage in human atherosclerotic plaques. An animal model study demonstrated that
knockout increased atherosclerotic plaque size and within-plaque content of monocytes/macrophages and smooth muscle cells, in apolipoprotein E-deficient mice fed a high fat diet.
We provide substantial evidence that the CAD risk variants at the 15q26.1 locus reduce FES expression in monocytes and that FES depletion results in larger atherosclerotic plaques with more monocytes/macrophages and smooth muscle cells. This study is the first demonstration that FES plays a protective role against atherosclerosis and suggests that enhancing FES activity could be a potentially novel therapeutic approach for CAD intervention.
Genome-wide association studies have identified chromosome 14q32 as a locus for coronary artery disease. The disease-associated variants fall in a hitherto uncharacterized gene called HHIPL1 ...(hedgehog interacting protein-like 1), which encodes a sequence homolog of an antagonist of hedgehog signaling. The function of HHIPL1 and its role in atherosclerosis are unknown.
HHIPL1 cellular localization, interaction with sonic hedgehog (SHH), and influence on hedgehog signaling were tested. HHIPL1 expression was measured in coronary artery disease-relevant human cells, and protein localization was assessed in wild-type and Apoe
(apolipoprotein E deficient) mice. Human aortic smooth muscle cell phenotypes and hedgehog signaling were investigated after gene knockdown. Hhipl1
mice were generated and aortic smooth muscle cells collected for phenotypic analysis and assessment of hedgehog signaling activity. Hhipl1
mice were bred onto both the Apoe
and Ldlr
(low-density lipoprotein receptor deficient) knockout strains, and the extent of atherosclerosis was quantified after 12 weeks of high-fat diet. Cellular composition and collagen content of aortic plaques were assessed by immunohistochemistry.
In vitro analyses revealed that HHIPL1 is a secreted protein that interacts with SHH and increases hedgehog signaling activity. HHIPL1 expression was detected in human smooth muscle cells and in smooth muscle within atherosclerotic plaques of Apoe
mice. The expression of Hhipl1 increased with disease progression in aortic roots of Apoe
mice. Proliferation and migration were reduced in Hhipl1 knockout mouse and HHIPL1 knockdown aortic smooth muscle cells, and hedgehog signaling was decreased in HHIPL1-deficient cells. Hhipl1 knockout caused a reduction of >50% in atherosclerosis burden on both Apoe
and Ldlr
knockout backgrounds, and lesions were characterized by reduced smooth muscle cell content.
HHIPL1 is a secreted proatherogenic protein that enhances hedgehog signaling and regulates smooth muscle cell proliferation and migration. Inhibition of HHIPL1 protein function might offer a novel therapeutic strategy for coronary artery disease.
Background and Purpose
Vascular tone is regulated by the relative contractile state of vascular smooth muscle cells (VSMCs). Several integrins directly modulate VSMC contraction by regulating calcium ...influx through L‐type voltage‐gated Ca2+ channels (VGCCs). Genetic variants in ITGA9, which encodes the α9 subunit of integrin α9β1, and SVEP1, a ligand for integrin α9β1, associate with elevated blood pressure; however, neither SVEP1 nor integrin α9β1 has reported roles in vasoregulation. We determined whether SVEP1 and integrin α9β1 can regulate VSMC contraction.
Experimental Approach
SVEP1 and integrin binding were confirmed by immunoprecipitation and cell binding assays. Human induced pluripotent stem cell‐derived VSMCs were used in in vitro Ca2+i studies, and aortas from a Svep1+/− knockout mouse model were used in wire myography to measure vessel contraction.
Key Results
We confirmed the ligation of SVEP1 to integrin α9β1 and additionally found SVEP1 to directly bind to integrin α4β1. Inhibition of SVEP1, integrin α4β1 or α9β1 significantly enhanced Ca2+i levels in isolated VSMCs to Gαq/11‐vasoconstrictors. This response was confirmed in whole vessels where a greater contraction to U46619 was seen in vessels from Svep1+/− mice compared to littermate controls or when integrin α4β1 or α9β1 was inhibited. Inhibition studies suggested that this effect was mediated via VGCCs, PKC and Rho A/Rho kinase dependent mechanisms.
Conclusions and Implications
Our studies reveal a novel role for SVEP1 and the integrins α4β1 and α9β1 in reducing VSMC contractility. This could provide an explanation for the genetic associations with blood pressure risk at the SVEP1 and ITGA9 loci.
Genetic variants in SVEP1 associate with elevated blood pressure. SVEP1 is expressed in VSMCs. SVEP1 plays a novel role in reducing vascular smooth muscle contractility.
The suppression of the bone morphogenetic protein (BMP) signaling pathway has been recently shown to promote adenoma-to-carcinoma transition in sporadic colon cancer. However, its role in the ...evolution of early preneoplastic changes to neoplasia remains elusive. In the present study, we aimed to investigate the gene expression levels of multiple extracellular BMP family constituents, including BMP ligands/receptors and inhibitors, during the early stages of inflammation-associated colon carcinogenesis. For that, we used the recently developed urokinase-type plasminogen activator (uPA)-deficient mouse model of colonic polypoidogenesis, in which adenomatous polyps arise several months after the induction of dextran sodium sulfate (DSS) colitis. In DSS-treated wild-type mice, the preneoplastic lesions which did not eventually evolve to adenomas resided in a colitic microenvironment characterized by a balanced upregulation of both BMP ligands, i.e., Bmp4/7 and BMP inhibitors, such as chordin, noggin, and gremlin-1. In the uPA-deficient tumor-promoting inflammatory microenvironment, however, there was a clear evidence for BMP pathway suppression. By contrast to DSS-treated wild-type controls, the inflammation-associated Bmp4 upregulation was abolished, and the BMP signaling suppression was further enhanced by a particularly high increase of gremlin-1 expression. These findings propose that BMP pathway suppression in colon cancer could be associated with very early stages of the preneoplasia-to-neoplasia sequence of events.
During the necropsy of a red fox Vulpes vulpes that had died from poisoning, we found a nodule of 2 × 3 cm in size in the gastric wall, which was caused by the nematode Spirocerca lupi. The ...histological features of the parasite include a smooth cuticle, large chords of the hypodermis, muscle cells of the polymyarian/coelomyarian type and large intestine cells with prominent microvillus border. The nodule was infiltrating different layers of the gastric wall and consisted of granulation tissue, with various inflammatory cells and active fibroblasts. This is the first report of S. lupi infection in the red fox in Greece.
Abstract Urokinase-type plasminogen activator (uPA) participates in cancer-related biologic processes, such as wound healing and inflammation. The present study aimed to investigate the effect of uPA ...deficiency on the long-term outcome of early life episodes of dextran sodium sulfate (DSS)–induced colitis in mice. Wild-type (WT) and uPA-deficient (uPA−/− ) BALB/c mice were treated with DSS or remained untreated. Mice were necropsied either 1 week or 7 months after DSS treatment. Colon samples were analyzed by histopathology, immunohistochemistry, ELISA, and real-time polymerase chain reaction. At 7 months, with no colitis evident, half of the uPA−/− mice had large colonic polypoid adenomas, whereas WT mice did not. One week after DSS treatment, there were typical DSS-induced colitis lesions in both WT and uPA−/− mice. The affected colon of uPA−/− mice, however, had features of delayed ulcer re-epithelialization and dysplastic lesions of higher grade developing on the basis of a significantly altered mucosal inflammatory milieu. The later was characterized by more neutrophils and macrophages, less regulatory T cells (Treg), significantly upregulated cytokines, including interleukin-6 (IL-6), IL-17, tumor necrosis factor-α, and IL-10, and lower levels of active transforming growth factor–β1 (TGF-β1) compared to WT mice. Dysfunctional Treg, more robust protumorigenic inflammatory events, and an inherited inability to produce adequate amounts of extracellular active TGF-β1 due to uPA deficiency are interlinked as probable explanations for the inflammatory-induced neoplasmatogenesis in the colon of uPA−/− mice.
omega 3 polyunsaturated fatty acids have anti-inflammatory properties and can be beneficial in the treatment of inflammatory diseases, such as ulcerative colitis. Dextran sodium sulphate (DSS) ...colitis in rats appears to mimic nearly all of the morphological characteristics and lesion distributions of ulcerative colitis. The purpose of the current study was to investigate the efficacy of omega 3 fatty acids in the treatment of experimental ulcerative colitis.
thirty-six Wistar rats were randomly assigned to group A or group B receiving 5% dextran sulfate sodium (DSS) in their drinking water for eight days. For the next eight days post-DSS, group A animals received tap-water, and group B animals were fed a nutritional solution containing high levels of omega 3 polyunsaturated fatty acids (ProSure®, Abbott Laboratories, Zwolle, Netherlands) once per day, administrated with a orogastric feeding tube.
animals fed an omega 3 rich diet exhibited a statistically significant increase in hematocrit and hemoglobin levels, compared to animals drinking tap water, and a trend towards histopathological and clinical improvement, with the administration of omega 3 fatty acids ameliorating epithelial erosion by day 8 post-DSS, but no statistically significant difference was observed between group A and group B animals at 4 or 8 days post-DSS. Also, a statistically significant increase in neutrophil infiltration was observed, as depicted by myelohyperoxidase activity.
our findings support a positive role of omega 3 polyunsaturated fatty acids supplementation in an experimental model of ulcerative colitis despite the increased colonic neutrophil infiltration. Further studies are needed in order to investigate the role of increased neutrophils in colonic mucosa.
Purpose: omega 3 polyunsaturated fatty acids have anti-inflammatory properties and can be beneficial in the treatment of inflammatory diseases, such as ulcerative colitis. Dextran sodium sulphate ...(DSS) colitis in rats appears to mimic nearly all of the morphological characteristics and lesion distributions of ulcerative colitis. The purpose of the current study was to investigate the efficacy of omega 3 fatty acids in the treatment of experimental ulcerative colitis. Methods: thirty-six Wistar rats were randomly assigned to group A or group B receiving 5% dextran sulfate sodium (DSS) in their drinking water for eight days. For the next eight days post-DSS, group A animals received tap-water, and group B animals were fed a nutritional solution containing high levels of omega 3 polyunsaturated fatty acids (ProSure®, Abbott Laboratories, Zwolle, Netherlands) once per day, administrated with a orogastric feeding tube. Results: animals fed an omega 3 rich diet exhibited a statistically significant increase in hematocrit and hemoglobin levels, compared to animals drinking tap water, and a trend towards histopathological and clinical improvement, with the administration of omega 3 fatty acids ameliorating epithelial erosion by day 8 post-DSS, but no statistically significant difference was observed between group A and group B animals at 4 or 8 days post-DSS. Also, a statistically significant increase in neutrophil infiltration was observed, as depicted by myelohyperoxidase activity. Conclusion: our findings support a positive role of omega 3 polyunsaturated fatty acids supplementation in an experimental model of ulcerative colitis despite the increased colonic neutrophil infiltration. Further studies are needed in order to investigate the role of increased neutrophils in colonic mucosa.
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