Deacetylation of cGAS by HDAC1 regulates vascular calcification by promoting autophagy.

AIMS: Vascular calcification is a major risk factor for cardiovascular mortality accompanied by DNA damage. Cyclic GMP-AMP synthase (cGAS) is a DNA sensor that is activated by genomic DNA damage. Here, we investigated the molecular mechanisms linking cGAS to vascular calcification. MAIN METHODS: Diabetic arteriosclerotic model and vascular calcification of primary vascular smooth muscle cells (VSMCs) were induced. Calcification was visualized with Alizarin red staining. Calcium deposition and alkaline phosphatase activity were analyzed by respectively kits. Deacetylation of cGAS was investigated using co-immunoprecipitation assay. KEY FINDINGS: Protein, but not mRNA, expression of cGAS is down-regulated in VSMCs and animal models of calcification. Overexpression of cGAS attenuated high-Pi induced calcification, calcium content and ALP activity. In addition, cGAS regulated VSMCs phenotype as overexpression of cGAS increased expression of contractile markers α-SMA and SM22α and decreased the expression of osteogenic markers RUNX2 and BMP2. The LC3II/LC3I ratio and Atg5 level were upregulated by cGAS overexpression. Under calcification-inducing conditions, HDAC1 deacetylates cGAS and inactivates it. HDAC1 knockdown by short hairpin HDAC1 reversed the cGAS-induced reduction in vascular calcification, as well as in autophagy. SIGNIFICANCE: HDAC1-induced cGAS deacetylation enhances vascular calcification and may therefore be a potential therapeutic target.

LncRNA MACC1-AS1 attenuates microvascular endothelial cell injury and promotes angiogenesis under hypoxic conditions via modulating miR-6867-5p/TWIST1 in human brain microvascular endothelial cells.

BACKGROUND: Hypoxia following ischemic stroke is a common cause of brain insults. Mounting evidence suggests that long non-coding RNAs (lncRNAs) play a vital role in regulating certain physiological and pathological processes including ischemic stroke. For the first time, the present study investigated the effects and mechanism of LncRNA MACC1-AS1 on hypoxia-induced human brain microvascular endothelial cells (HBMECs). METHODS: LncRNA MACC1-AS1 levels in HBMECs were detected via reverse transcription quantitative polymerase chain reaction (RT-qPCR) assay. Reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT), were detected using their respective kits. Flow cytometry and clone formation assay were performed to evaluate the effects of lncRNA MACC1-AS1 on cell apoptosis and cell proliferation respectively. Angiogenesis capacity was evaluated via tube formation assay. Transwell migration assay was performed for assessment of cell migration, Western blot assay was performed for measurement of Twist1 and VE-cadherin level, and permeability assay was performed for evaluation of the cell barrier function. The target gene was predicted via bioinformatics online tool and validated through luciferase reporter assay and RNA pull-down assay. RESULTS: LncRNA MACC1-AS1 was downregulated in hypoxia-induced HBMECs. Overexpression of LncRNA MACC1-AS1 reduced cell apoptosis and oxidative stress, while promoting cell proliferation, migration, and angiogenesis. Moreover, LncRNA MACC1-AS1 overexpression reduced cell permeability and elevated VE-cadherin level, which contributed to maintaining cell barrier function. TWIST1 was validated as the target of miR-6867-5p which was further targeted by lncRNA MACC1-AS1. Thus, LncRNA MACC1-AS1 functions in hypoxia-induced HBMECs by regulating miR-6867-5p/TWIST1. CONCLUSIONS: In this study, we found that LncRNA MACC1-AS1 exerted a protective role in hypoxia-induced HBMECs via regulating miR-6867-5p/TWIST1, indicating a new therapeutic strategy for future ischemic stroke therapy.

Predisposition of Inflammatory Bowel Disease Is Influenced by IL-8, IL-10, and IL-18 Polymorphisms: A Meta-Analysis.

BACKGROUND: Whether interleukin (IL)-8, IL-10, and IL-18 polymorphisms influence predisposition of inflammatory bowel disease (IBD) remains uncertain. OBJECTIVES: The authors conducted a meta-analysis to explore relationships between IL-8, IL-10, or IL-18 polymorphisms and predisposition of IBD by merging the results of eligible literatures. METHODS: A thorough literature search in MEDLINE, Embase, Wanfang, VIP, and CNKI was conducted by the authors to identify eligible literatures, and 33 literatures were finally selected for merged analyses. RESULTS: We found that genotypic frequencies of IL-8 rs4073, IL-10 rs1800871, IL-10 rs1800872, and IL-10 rs1800896 polymorphisms among cases with IBD and population-based controls differed significantly. Moreover, we found that genotypic frequencies of IL-8 rs4073, IL-10 rs1800871, and IL-18 rs1946518 polymorphisms among cases with IBD and population-based controls of Asian origin differed significantly, whereas genotypic frequency of IL-10 rs1800896 polymorphism among cases with IBD and population-based controls of Caucasian origin also differed significantly. Furthermore, genotypic frequency of IL-18 rs187238 polymorphism among cases with Crohn's disease (CD) and population-based controls also differed significantly. CONCLUSIONS: The present meta-analysis shows that IL-8 rs4073, IL-10 rs1800871, IL-10 rs1800872, IL-10 rs1800896, and IL-18 rs1946518 polymorphisms may influence predisposition of IBD. Furthermore, IL-18 rs187238 polymorphism may influence predisposition of CD, but not predisposition of ulcerative colitis.

VGLL4 Protects against Oxidized-LDL-Induced Endothelial Cell Dysfunction and Inflammation by Activating Hippo-YAP/TEAD1 Signaling Pathway.

Vestigial-like 4 (VGLL4) has been found to have multiple functions in tumor development; however, its role in cardiovascular disease is unknown. The aim of this study was to investigate the effect of VGLL4 on the dysfunction and inflammatory response of Ox-LDL-induced human umbilical vein endothelial cells (HUVECs) and its mechanism, so as to provide a new theoretical basis for the diagnosis and treatment of atherosclerosis. In the present study, the protective activity of VGLL4 inhibiting Ox-LDL-induced apoptosis, oxidative stress, inflammation, and injury as well as its molecular mechanisms was examined using human umbilical vein endothelial cells (HUVECs). The results showed that the expression of VGLL4 was decreased with the increase of Ox-LDL concentration in HUVECs. In addition, the functional study found that VGLL4 overexpression alleviated Ox-LDL-induced oxidative stress, inflammation, and dysfunction and inhibited apoptosis. Further research found that VGLL4 regulated Hippo-YAP/TEAD1 signaling pathway, and the Hippo-YAP/TEAD1 signaling pathway was involved in the protective mechanism of VGLL4 on HUVECs. In conclusion, it suggests that VGLL4 protects against oxidized-LDL-induced endothelial cell dysfunction by activating the Hippo-YAP/TEAD1 signaling pathway.

Identification of ß-catenin target genes in colorectal cancer by interrogating gene fitness screening data.

ß-catenin regulates its target genes which are associated with proliferation, differentiation, migration and angiogenesis, and the dysregulation of Wnt/ß-catenin signaling facilitates hallmarks of colorectal cancer (CRC). Identification of ß-catenin targets and their potential roles in tumorigenesis has gained increased interest. However, the number of identified targets remains limited. The present study implemented a novel strategy, interrogating gene fitness profiles derived from large-scale RNA interference and CRISPR-CRISPR associated protein 9 screening data to identify ß-catenin target genes in CRC cell lines. Using these data sets, pair wise gene fitness similarities were determined which highlighted a total of 13 genes whose functions were highly correlated with ß-catenin. It was further demonstrated that the expression of these genes were altered in CRC, illustrating their potential roles in the progression of CRC. The present study further demonstrated that these targets could be used to predict disease-free survival in CRC. In conclusion, the findings provided novel approaches for the identification of ß-catenin targets, which may become prognostic biomarkers or drug targets for the management of CRC.

Knockdown of SRPX2 inhibits the proliferation, migration, and invasion of prostate cancer cells through the PI3K/Akt/mTOR signaling pathway.

Sushi repeat-containing protein X-linked 2 (SRPX2), a novel chondroitin sulfate proteoglycan, is reported to play a critical role in tumorigenesis. However, the expression and functional role of SRPX2 in prostate cancer have not been defined. Thus, the aim of this study was to investigate the expression and functional role of SRPX2 in human prostate cancer. Our results showed that the expression of SRPX2 was obviously increased in human prostate cancer tissues and cell lines. In addition, knockdown of SRPX2 inhibited the proliferation, migration, and invasion of prostate cancer cells, as well as prevented the epithelial-mesenchymal transition process in prostate cancer cells. Mechanically, knockdown of SRPX2 efficiently inhibited the activation of PI3K/Akt/mTOR pathway in prostate cancer cells. Taken together, these data demonstrated that knockdown of SRPX2 inhibits the proliferation and metastasis in human prostate cancer cells, partly through the PI3K/Akt/mTOR signaling pathway. Thus, SRPX2 may be a novel therapeutic target for the treatment of prostate cancer.

Adipose differentiation­related protein knockdown inhibits vascular smooth muscle cell proliferation and migration and attenuates neointima formation.

Vascular smooth muscle cells (VSMCs) have an important role in atherosclerosis development. Evidence has demonstrated that adipose differentiation­related protein (ADRP) is associated with foam cell formation and atherosclerosis progression. However, to the best of our knowledge, no previous studies have investigated the role of ADRP knockdown in platelet­derived growth factor (PDGF)­stimulated proliferation and migration of VSMCs in vitro. Furthermore, the effect of ADRP knockdown on neointima formation in vivo remains unclear. In the present study, primary human aortic VSMCs were incubated with PDGF following ADRP small interfering (si)RNA transfection. Cell viability, migration and cell cycle distribution were analyzed by MTT, wound healing and Transwell assays and flow cytometry, respectively. Extracellular signal­regulated kinase (ERK), phosphorylated (p)­ERK, Akt, p­Akt, proliferating cell nuclear antigen (PCNA), matrix metalloproteinase (MMP)­2 and MMP­9 protein levels were determined by western blotting. Apolipoprotein E-/- mice fed an atherogenic diet were injected with siADRP or control siRNA twice a week. After 3 weeks of therapy, aortas were excised and ADRP mRNA and protein expression was determined. Neointima formation was assessed by hematoxylin and eosin staining. The results of the current study demonstrated that ADRP knockdown significantly inhibited PDGF­induced increases in VSMC viability, caused G1 phase cell cycle arrest and decreased PCNA expression. Knockdown of ADRP inhibited PDGF­induced migration of VSMCs by reducing MMP protein expression and activity. In addition, the present study also demonstrated that ADRP knockdown inhibited ERK and Akt signaling pathways in response to PDGF. Furthermore, siADRP administration suppressed neointima formation in the mouse model. The results of the present study indicate that ADRP may be a potential target for the treatment of atherosclerosis.

Identification of candidate target genes for human peripheral arterial disease using weighted gene co­expression network analysis.

The aim of the present study was to identify the potential treatment targets of peripheral arterial disease (PAD) and provide further insights into the underlying mechanism of PAD, based on a weighted gene co­expression network analysis (WGCNA) method. The mRNA expression profiles (accession. no. GSE27034), which included 19 samples from patients with PAD and 18 samples from normal control individuals were extracted from the Gene Expression Omnibus database. Subsequently, the differentially expressed genes (DEGs) were obtained using the Limma package and the co­expression network modules were screened using the WGCNA approach. In addition, the protein­protein interaction network for the DEGs in the most significant module was constructed using Cytoscape software. Functional enrichment analyses of the DEGs in the most significant module were also performed using the Database for Annotation, Visualization and Integrated Discovery and Kyoto Encyclopedia of Genes and Genomes (KEGG) Orthology­Based Annotation System, respectively. A total of 148 DEGs were identified in PAD, which were used to construct the WGCN, in which two modules (gray module and turquoise module) were identified, with the gray module exhibiting a higher gene significance (GS) value than the turquoise module. In addition, a co­expression network was constructed for 60 DEGs in the gray module. The functional enrichment results showed that the DEGs in the gray module were enriched in five Gene Ontology terms and four KEGG pathways. For example, cyclin­dependent kinase inhibitor 1A (CDKN1A), FBJ murine osteosarcoma viral oncogene homolog (FOS) and prostaglandin­endoperoxide synthase 2 (PTGS2) were enriched in response to glucocorticoid stimulus. The results of the present study suggested that DEGs in the gray module, including CDKN1A, FOS and PTGS2, may be associated with the pathogenesis of PAD, by modulating the cell cycle, and may offer potential for use as candidate treatment targets for PAD.