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The aim of the present study was to take osteopontin (OPN) as molecular target to study its effects on injured intima model of carotid artery in rat using perivascular transfer of OPN-small interference RNA (siRNA). OPN mRNA in cultured VSMCs was quantified by real-time RT-PCR, and OPN-siRNA-002 was determined as the most sensitive sequence and used as transfected siRNA in the subsequent animal experiments. We established rat carotid arterial intima-injured model with balloon-injured method, and then perivascularly transfected OPN-siRNA-002 to study the role of OPN-siRNA in regulating several related genes including proliferating cell nuclear antigen (PCNA), transforming growth factor β1(TGF-β1), matrix metalloproteinase-2 (MMP-2), and matrix metalloproteinase-14 (MMP-14), as well as its role in neointimal formation. OPN mRNA and protein decreased about 50 % with corresponding decrease in intima thickness after transfecting with specific OPN-siRNA-002 compared with Pluronic control group and OPN-SCR-siRNA group on each time point (n = 6, p < 0.001), and this inhibiting effects persisted up to 14 days after balloon injury. PCNA, TGF-β1, MMP-2, and MMP-14 mRNA and protein correlated directly with the respective levels of OPN, suggesting its functions via regulating these downstream factors (n = 6, p < 0.001). OPN may be a potential target gene in reducing the risk for arterial restenosis after vascular intervention.

Early growth response factor-1 (Egr-1) and osteopontin (OPN) play important roles in the migration and proliferation of vascular smooth muscle cells (VSMC), but little is known about their relationship. Therefore, we transfected VSMCs with either Egr-1 cDNA, Opn cDNA, a DNA enzyme designed to target Egr-1 (ED5), or antisense Opn oligodeoxynucleotides and examined changes in Egr-1 and OPN expression at the mRNA and protein levels. OPN expression levels were increased in cells that were stably transfected with Egr-1 cDNA. By contrast, both Egr-1 and OPN expression were reduced when ED5 was transfected into Egr-1-expressing cells. Similarly, Opn transfection upregulated Egr-1 levels, while Opn anti-sense oligodeoxynucleotide transfection decreased Egr-1 expression. ChIP analysis showed that Egr-1 binds to the Opn gene promoter. Furthermore, treatment with the extracellular-regulated protein kinase (ERK) inhibitor PD98059 inhibited the upregulation of Egr-1 by OPN. We find that Egr-1 and OPN positively regulate each other in VSMCs.

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Objectives: Depletion of early growth response factor-1 (Egr-1) by a DNA enzyme, ED5, inhibits neointimal hyperplasia (NH) following vascular injury by an unknown mechanism. The aim of this study was to characterize the effects of ED5 in a rat carotid injury model in order to elucidate the mechanism by which ED5 inhibits NH. Methods: ED5 was transfected into the arterial wall of Wistar rats using FuGENE6 transfection reagent following artery balloon injury. Hematoxylin and eosin staining, immunohistochemistry, real-time reverse transcription polymerase chain reaction and Western blotting analysis were used to characterize the response to ED5. Results: NH decreased significantly in the ED5- plus FuGENE6-treated rats (p < 0.05) compared with the control groups, and this was accompanied by a reduced inflammatory response. Egr-1 mRNA and protein levels were significantly decreased in the ED5-treated group, as expected. The decrease in Egr-1 was accompanied by decreases in the mRNA and protein levels of PDGF-BB, Cyclin D1, CDK4, MCP-1, and ICAM-1 (p < 0.05). Conclusions: Transfection of the Egr-1-specific synthetic DNA enzyme ED5 significantly reduced NH after injury in rats, at least in part, as a result of decreased expression of downstream proliferative genes such as PDGF-BB, Cyclin D1, CDK4, and the inflammatory factors MCP-1 and ICAM-1.

The Hippo signaling pathway is involved in the formation and development of the cardiovascular system. In the present study, the effects of WWC family member 3 (WWC3) on vascular smooth muscle cells (VSMCs) following injury were investigated, in addition to the associated mechanisms underlying this process. Platelet-derived growth factor BB (PDGF-BB) was used as a cell injury factor, and rats with balloon injuries were used as a model of carotid intimal injury. Furthermore, the expression levels of WWC3 in VSMCs and arteries post-injury were investigated, in addition to the effect of WWC3 on the proliferation and migration of VSMCs. The results demonstrated that following injury, WWC3 expression was suppressed in VSMCs and the rat carotid artery, and the activity of the Hippo signaling pathway was significantly downregulated. In addition, the expression of YY1-associated protein-1 (YAP) and a number of its downstream target genes, including connective tissue growth factor (CTGF), were enhanced, thus enhancing the proliferation and migration of VSMCs. Knockdown of WWC3 suppressed the levels of large tumor suppressor kinase 1 (LATS1) expression and YAP phosphorylation, and the expression of YAP, CTGF and cyclin E was subsequently enhanced, thus promoting cell proliferation and migration. Similar results were obtained following overexpression of WWC3. Treatment with PDGF-BB was revealed to suppress the proliferation and migration of VSMCs transfected with the WWC3 plasmid, compared with VSMCs transfected with an empty vector. The present study demonstrated that WWC3 may interact with LATS1 in order to upregulate the Hippo signaling pathway via co-immunoprecipitation and enhancement of the phosphorylation of LATS1, in addition to the corresponding suppression of the nuclear import of YAP. However, VSMCs transfected with WWC3 plasmid with a deletion of the WW domain fail to exhibit this effect. These results suggested that WWC3 expression is downregulated in VSMCs during neointimal hyperplasia following injury (PDGF-BB stimulation or balloon injury). WWC3 upregulates the activity of the Hippo signaling pathway, and weakens the proliferation and migration of VSMCs. Furthermore, the results of the present study suggested that WWC3 may interact with LATS1 to promote the phosphorylation of YAP and reduce its nuclear translocation, upregulate the activity of the Hippo pathway, and suppress the proliferation and migration of VSMCs following injury.

Fully Convolutional One-Stage Object Detection (FCOS) is a one-stage anchor-free object detection model. The detection accuracy even exceeds some two-stage and anchor-base object detection model, but it still has the problem of slow inference speed. Aiming at the problem that the speed of FCOS algorithm cannot meet the requirements of real-time detection, a lightweight object detection model Improved MobileNetV2-FCOS (IM-FCOS) is proposed. First of all, the MobileNetV2 structure is introduced as the backbone network of FCOS. By replacing the ordinary convolution with a depth separable convolution, the model size is reduced while improving the model detection speed. Then, use the Sobel module to add the directional gradient extracted by the Sobel convolution, increase the dimension of the input data, and enhance the edge semantic information. Using the Mish activation function to replace the Rectified Linear Unit (ReLU) activation function in the Head part of the model, retain the semantic information of the negative part, and improve the model generalization ability. Use Distance Intersection over Union (DIoU) as an evaluation indicator to more accurately describe the similarity between the predicted frame and the ground truth, and optimize the regression loss. Optimize the model algorithm from the above three aspects, and finally the experimental results on the Microsoft Common Objects in Context 2014 (MS-COCO2014) data set show that the mean Average Precision (mAP) of the IM-FCOS algorithm reaches 34.1, and Frames Per Second (FPS) reaches 31, which can meet the need for real-time detection.