RhoGDI3 at the trans-Golgi network participates in NLRP3 inflammasome activation, VSMC phenotypic modulation, and neointima formation.

BACKGROUND AND AIMS: The pathological roles and mechanisms of Rho-specific guanine nucleotide dissociation inhibitor 3 (RhoGDI3) in vascular smooth muscle cell (VSMC) phenotypic modulation and neointima formation are currently unknown. This study aimed to investigate how RhoGDI3 regulates the Nod-like receptor protein 3 (NLRP3) inflammasome in platelet-derived growth factor-BB (PDGF-BB)-induced neointima formation. METHODS: For in vitro assays, human aortic VSMCs (HA-VSMCs) were transfected with pcDNA3.1-GDI3 and RhoGDI3 siRNA to overexpress and knockdown RhoGDI3, respectively. HA-VSMCs were also treated with an NLRP3 inhibitor (CY-09) or agonist (NSS). Protein transcription and expression, cell proliferation and migration, Golgi morphology, and protein binding and colocalization were measured. For the in vivo assays, balloon injury (BI) rats were injected with recombinant adenovirus carrying RhoGDI3 shRNA. Carotid arterial morphology, protein expression and colocalization, and activation of the NLRP3 inflammasome were measured. RESULTS: PDGF-BB treatment induced transcription and expression of RhoGDI3 through PDGF receptor αß (PDGFRαß) rather than PDGFRαα or PDGFRßß in HA-VSMCs. RhoGDI3 suppression blocked PDGF-BB-induced VSMC phenotypic transformation. In contrast, RhoGDI3 overexpression further promoted PDGF-BB-induced VSMC dedifferentiation. The in vivo results also confirmed that RhoGDI3 expressed in VSMCs participated in neointima formation and muscle fiber and collagen deposition caused by balloon injury. In addition, PDGF-BB increased binding of RhoGDI3 to NLRP3 and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) at the trans-Golgi membrane, which depended on the normal Golgi network. However, recruitment of NLRP3 and ASC to the trans-Golgi network after PDGF-BB treatment was independent of RhoGDI3. Moreover, RhoGDI3 knockdown significantly inhibited ASC expression and NLRP3 inflammasome assembly and activation and reduced NLRP3 protein stability in PDGF-BB-treated HA-VSMCs. Inhibiting NLRP3 effectively prevented PDGF-BB-induced VSMC phenotypic modulation, and an NLRP3 agonist reversed the decline in VSMC phenotypic transformation caused by RhoGDI3 knockdown. Furthermore, RhoGDI3 suppression reduced the protein levels and assembly of NLRP3 and ASC, and the activation of the NLRP3 inflammasome in VSMCs in a rat balloon injury model. CONCLUSIONS: The results of this study reveal a novel mechanism through which RhoGDI3 regulates VSMC phenotypic modulation and neointima formation by activating the NLRP3 inflammasome.

Protective Role of Cytochrome C Oxidase 5A (COX5A) against Mitochondrial Disorder and Oxidative Stress in VSMC Phenotypic Modulation and Neointima Formation.

BACKGROUND: The pathological role of cytochrome c oxidase 5A (COX5A) in vascular neointima formation remains unknown. AIM: This study aims to investigate the role of COX5A on platelet-derived growth factor BB (PDGFBB)- mediated smooth muscle phenotypic modulation and neointima formation and clarify the molecular mechanisms behind this effect. METHODS: For in vitro assays, human aortic vascular smooth muscle cells (HA-VSMCs) were transfected with pcDNA3.1-COX5A and COX5A siRNA to overexpress and knockdown COX5A, respectively. Mitochondrial complex IV activity, oxygen consumption rate (OCR), H2O2 and ATP production, reactive oxygen species (ROS) generation, cell proliferation, and migration were measured. For in vivo assays, rats after balloon injury (BI) were injected with recombinant lentivirus carrying the COX5A gene. Mitochondrial COX5A expression, carotid arterial morphology, mitochondrial ultrastructure, and ROS were measured. RESULTS: The results showed that PDGF-BB reduced the level and altered the distribution of COX5A in mitochondria, as well as reduced complex IV activity, ATP synthesis, and OCR while increasing H2O2 synthesis, ROS production, and cell proliferation and migration. These effects were reversed by overexpression of COX5A and aggravated by COX5A knockdown. In addition, COX5A overexpression attenuated BI-induced neointima formation, muscle fiber area ratio, VSMC migration to the intima, mitochondrial ultrastructural damage, and vascular ROS generation. CONCLUSION: The present study demonstrated that COX5A protects VSMCs against phenotypic modulation by improving mitochondrial respiratory function and attenuating mitochondrial damage, as well as reducing oxidative stress, thereby preventing neointima formation.

Angiotensin II Inhibits Adipogenic Differentiation and Promotes Mature Adipocyte Browning through the Corepressor CtBP1.

The mechanisms of angiotensin II (Ang II) on regulating adipogenic differentiation and function remain unknown. In this study, we focus on revealing the role of C-terminal-binding protein 1 (CtBP1) on Ang II-mediated adipogenic differentiation and mature adipocyte browning. Amounts of 3T3-L1 and CtBP1-KO 3T3-L1 were treated with Ang II for 24 h and then induced adipogenic differentiation, or cells were first induced differentiation and then treated with Ang II. The expressions of CtBP1 and adipogenic markers were checked by Western blot. Transcription of CtBP1 was assayed by Real-time RT-PCR. Lipid droplet formation and size were detected by Oil Red O. Mitochondrial content and reactive oxygenspecies (ROS) were detected by Mito-tracker and MitoSOX. Mitochondrial respiratory function was detected with the corresponding kits. Mitochondrial membrane potential (MMP) (∆Ψm) was assayed by JC-1. The results show that Ang II promoted CtBP1 transcription and expression via AT1 receptor during 3T3-L1 adipogenic differentiation. Ang II significantly inhibited lipid droplet formation and adipogenic markers expression in 3T3-L1 differentiation, which was blocked by CtBP1 knockout. In mature 3T3-L1, Ang II treatment increased uncoupling protein-1 (UCP-1) expression and the number of lipid droplets, and also reduced lipid droplet size and single cell lipid accumulation, which was reversed by CtBP1 knockout. In addition, Ang II treatment enhanced mitochondrial numbers, ATP production, oxygen consumption rate (OCR) and ROS generation, and reduced MMP (∆Ψm) via CtBP1 in mature 3T3-L1 adipocytes. In conclusion, this study demonstrates that CtBP1 plays a key role in the inhibitory effect of Ang II on adipogenesis. Moreover, Ang II regulates the function of mature adipocyte via CtBP1, including promoting adipocyte browning, mitochondrial respiration and ROS generation.

TGFß1 induces myofibroblast transdifferentiation via increasing Smad-mediated RhoGDI-RhoGTPase signaling.

This study serves to investigate the effects of the Smad pathway on TGFß1-mediated RhoGDI expression and its binding to RhoGTPases in myofibroblast transdifferentiation. Myofibroblast transdifferentiation was induced by TGFß1 in vitro. Cells were pretreated with different siRNAs or inhibitors. Myofibroblast transdifferentiation was detected by immunohistochemistry. Immunofluorescence was used to observe the nuclear translocation of Smad4, and PSR (Picrositius Red) staining was used to measure collagen concentration. TGFß1 induced the phosphorylation of Smad2/3 and the nuclear translocation of Smad4 in human aortic adventitial fibroblasts (HAAFs). Furthermore, TGFß1 increased the expression of RhoGDI and its binding to RhoGTPases. Nevertheless, inhibition of Smad2/3 phosphorylation decreased TGFß1-induced RhoGDI1/2 expressions and RhoGDI2-RhoGTPases interactions. These data suggested that the inhibition of Smad phosphorylation attenuates myofibroblast transdifferentiation by inhibiting TGFß1-induced RhoGDI1/2 expressions and RhoGDI-RhoGTPases signaling.

An Intelligent Rice Yield Trait Evaluation System Based on Threshed Panicle Compensation.

High-throughput phenotyping of yield-related traits is meaningful and necessary for rice breeding and genetic study. The conventional method for rice yield-related trait evaluation faces the problems of rice threshing difficulties, measurement process complexity, and low efficiency. To solve these problems, a novel intelligent system, which includes an integrated threshing unit, grain conveyor-imaging units, threshed panicle conveyor-imaging unit, and specialized image analysis software has been proposed to achieve rice yield trait evaluation with high throughput and high accuracy. To improve the threshed panicle detection accuracy, the Region of Interest Align, Convolution Batch normalization activation with Leaky Relu module, Squeeze-and-Excitation unit, and optimal anchor size have been adopted to optimize the Faster-RCNN architecture, termed 'TPanicle-RCNN,' and the new model achieved F1 score 0.929 with an increase of 0.044, which was robust to indica and japonica varieties. Additionally, AI cloud computing was adopted, which dramatically reduced the system cost and improved flexibility. To evaluate the system accuracy and efficiency, 504 panicle samples were tested, and the total spikelet measurement error decreased from 11.44 to 2.99% with threshed panicle compensation. The average measuring efficiency was approximately 40 s per sample, which was approximately twenty times more efficient than manual measurement. In this study, an automatic and intelligent system for rice yield-related trait evaluation was developed, which would provide an efficient and reliable tool for rice breeding and genetic research.

Field rice panicle detection and counting based on deep learning.

Panicle number is directly related to rice yield, so panicle detection and counting has always been one of the most important scientific research topics. Panicle counting is a challenging task due to many factors such as high density, high occlusion, and large variation in size, shape, posture et.al. Deep learning provides state-of-the-art performance in object detection and counting. Generally, the large images need to be resized to fit for the video memory. However, small panicles would be missed if the image size of the original field rice image is extremely large. In this paper, we proposed a rice panicle detection and counting method based on deep learning which was especially designed for detecting rice panicles in rice field images with large image size. Different object detectors were compared and YOLOv5 was selected with MAPE of 3.44% and accuracy of 92.77%. Specifically, we proposed a new method for removing repeated detections and proved that the method outperformed the existing NMS methods. The proposed method was proved to be robust and accurate for counting panicles in field rice images of different illumination, rice accessions, and image input size. Also, the proposed method performed well on UAV images. In addition, an open-access and user-friendly web portal was developed for rice researchers to use the proposed method conveniently.

An Intelligent Analysis Method for 3D Wheat Grain and Ventral Sulcus Traits Based on Structured Light Imaging.

The wheat grain three-dimensional (3D) phenotypic characters are of great significance for final yield and variety breeding, and the ventral sulcus traits are the important factors to the wheat flour yield. The wheat grain trait measurements are necessary; however, the traditional measurement method is still manual, which is inefficient, subjective, and labor intensive; moreover, the ventral sulcus traits can only be obtained by destructive measurement. In this paper, an intelligent analysis method based on the structured light imaging has been proposed to extract the 3D wheat grain phenotypes and ventral sulcus traits. First, the 3D point cloud data of wheat grain were obtained by the structured light scanner, and then, the specified point cloud processing algorithms including single grain segmentation and ventral sulcus location have been designed; finally, 28 wheat grain 3D phenotypic characters and 4 ventral sulcus traits have been extracted. To evaluate the best experimental conditions, three-level orthogonal experiments, which include rotation angle, scanning angle, and stage color factors, were carried out on 125 grains of 5 wheat varieties, and the results demonstrated that optimum conditions of rotation angle, scanning angle, and stage color were 30°, 37°, black color individually. Additionally, the results also proved that the mean absolute percentage errors (MAPEs) of wheat grain length, width, thickness, and ventral sulcus depth were 1.83, 1.86, 2.19, and 4.81%. Moreover, the 500 wheat grains of five varieties were used to construct and validate the wheat grain weight model by 32 phenotypic traits, and the cross-validation results showed that the R 2 of the models ranged from 0.77 to 0.83. Finally, the wheat grain phenotype extraction and grain weight prediction were integrated into the specialized software. Therefore, this method was demonstrated to be an efficient and effective way for wheat breeding research.

Value of red cell distribution width-to-platelet ratio as a predictor for morbidity and mortality in neonatal intensive care unit.

Scoring neonatal acute physiology is significant for improving the survival rate of neonates in neonatal intensive care units (NICU). Red blood cell distribution width to platelet ratio (RPR) has been used to evaluate physiology of multiple diseases. However, the value of RPR as a predictor for morbidity and mortality in NICU remains unclear. The score for neonatal acute physiology and perinatal extension II (SNAPE-II) was used to evaluate the physiology and separate neonates into Mild (n = 45), Moderate (n = 45) and Severe (n = 45) groups. White blood cell count (WBC), procalcitonin (PCT) and C-reactive protein (CRP) in cord blood were examine. Spearman's correlation and receiver operating characteristic analysis were performed to demonstrated the correlations of these indicators. There was a positive correlation between the SNAPE-II scores and RPR in neonates in NICU. The WBC, PCT and CRP levels increased with the upregulation of SNAPE-II scores in neonates in NICU and there were positive correlations between RPR and WBC, PCT and CRP, respectively. RPR could be used as a supplementary predictor for the evaluation of neonatal morbidity and mortality in NICU beside SNAPE-II.

Cereal grain 3D point cloud analysis method for shape extraction and filled/unfilled grain identification based on structured light imaging.

Cereals are the main food for mankind. The grain shape extraction and filled/unfilled grain recognition are meaningful for crop breeding and genetic analysis. The conventional measuring method is mainly manual, which is inefficient, labor-intensive and subjective. Therefore, a novel method was proposed to extract the phenotypic traits of cereal grains based on point clouds. First, a structured light scanner was used to obtain the grains point cloud data. Then, the single grain segmentation was accomplished by image preprocessing, plane fitting, region growth clustering. The length, width, thickness, surface area and volume was calculated by the specified analysis algorithms for grain point cloud. To demonstrate this method, experimental materials included rice, wheat and corn were tested. Compared with manual measurement results, the average measurement error of grain length, width and thickness was 2.07%, 0.97%, 1.13%, and the average measurement efficiency was about 9.6 s per grain. In addition, the grain identification model was conducted with 25 grain phenotypic traits, using 6 machine learning methods. The results showed that the best accuracy for filled/unfilled grain classification was 90.184%.The best accuracy for indica and japonica identification was 99.950%, while for different varieties identification was only 47.252%. Therefore, this method was proved to be an efficient and effective way for crop research.

StomataScorer: a portable and high-throughput leaf stomata trait scorer combined with deep learning and an improved CV model.

To measure stomatal traits automatically and nondestructively, a new method for detecting stomata and extracting stomatal traits was proposed. Two portable microscopes with different resolutions (TipScope with a 40× lens attached to a smartphone and ProScope HR2 with a 400× lens) are used to acquire images of living stomata in maize leaves. FPN model was used to detect stomata in the TipScope images and measure the stomata number and stomatal density. Faster RCNN model was used to detect opening and closing stomata in the ProScope HR2 images, and the number of opening and closing stomata was measured. An improved CV model was used to segment pores of opening stomata, and a total of 6 pore traits were measured. Compared to manual measurements, the square of the correlation coefficient (R2 ) of the 6 pore traits was higher than 0.85, and the mean absolute percentage error (MAPE) of these traits was 0.02%-6.34%. The dynamic stomata changes between wild-type B73 and mutant Zmfab1a were explored under drought and re-watering condition. The results showed that Zmfab1a had a higher resilience than B73 on leaf stomata. In addition, the proposed method was tested to measure the leaf stomatal traits of other nine species. In conclusion, a portable and low-cost stomata phenotyping method that could accurately and dynamically measure the characteristic parameters of living stomata was developed. An open-access and user-friendly web portal was also developed which has the potential to be used in the stomata phenotyping of large populations in the future.

Comparative Proteomic Analysis of tPVAT during Ang II Infusion.

Perivascular adipose tissue (PVAT) homeostasis plays an important role in maintaining vascular function, and PVAT dysfunction may induce several pathophysiological situations. In this study, we investigated the effect and mechanism of the local angiotensin II (Ang II) on PVAT. High-throughput comparative proteomic analysis, based on TMT labeling combined with LC-MS/MS, were performed on an in vivo Ang II infusion mice model to obtain a comprehensive view of the protein ensembles associated with thoracic PVAT (tPVAT) dysfunction induced by Ang II. In total, 5037 proteins were confidently identified, of which 4984 proteins were quantified. Compared with the saline group, 145 proteins were upregulated and 146 proteins were downregulated during Ang II-induced tPVAT pathogenesis. Bioinformatics analyses revealed that the most enriched GO terms were annotated as gene silencing, monosaccharide binding, and extracellular matrix. In addition, some novel proteins, potentially associated with Ang II infusion, were identified, such as acyl-CoA carboxylase α, very long-chain acyl-CoA synthetase (ACSVL), uncoupling protein 1 (UCP1), perilipin, RAS protein-specific guanine nucleotide-releasing factor 2 (RasGRF2), and hypoxia inducible factor 1α (HIF-1α). Ang II could directly participate in the regulation of lipid metabolism, transportation, and adipocyte differentiation by affecting UCP1 and perilipin. Importantly, the key KEGG pathways were involved in fatty acid biosynthesis, FABP3-PPARα/γ, RasGRF2-ERK-HIF-1α, RasGRF2-PKC-HIF-1α, and STAT3-HIF-1α axis. The present study provided the most comprehensive proteome profile of mice tPVAT and some novel insights into Ang II-mediated tPVAT dysfunction and will be helpful for understanding the possible relationship between local RAS activation and PVAT dysfunction.

RhoGDI1-Cdc42 Signaling Is Required for PDGF-BB-Induced Phenotypic Transformation of Vascular Smooth Muscle Cells and Neointima Formation.

RhoGTPase is involved in PDGF-BB-mediated VSMC phenotypic modulation. RhoGDIs are key factors in regulating RhoGTPase activation. In the present study, we investigated the regulatory effect of RhoGDI1 on the activation of RhoGTPase in VSMC transformation and neointima formation. Western blot and co-immunoprecipitation assays showed that the PDGF receptor inhibition by crenolanib promoted RhoGDI1 polyubiquitination and degradation. Inhibition of RhoGDI1 degradation via MG132 reversed the decrease in VSMC phenotypic transformation. In addition, RhoGDI1 knockdown significantly inhibited VSMC phenotypic transformation and neointima formation in vitro and in vivo. These results suggest that PDGF-BB promotes RhoGDI1 stability via the PDGF receptor and induces the VSMC synthetic phenotype. The co-immunoprecipitation assay showed that PDGF-BB enhanced the interaction of RhoGDI1 with Cdc42 and promoted the activation of Cdc42; these enhancements were blocked by crenolanib and RhoGDI1 knockdown. Moreover, RhoGDI1 knockdown and crenolanib pretreatment prevented the localization of Cdc42 to the plasma membrane (PM) to activate and improve the accumulation of Cdc42 on endoplasmic reticulum (ER). Furthermore, Cdc42 inhibition or suppression significantly reduced VSMC phenotypic transformation and neointima formation in vitro and in vivo. This study revealed the novel mechanism by which RhoGDI1 stability promotes the RhoGDI1-Cdc42 interaction and Cdc42 activation, thereby affecting VSMC phenotypic transformation and neointima formation.

Ang II Promotes SUMO2/3 Modification of RhoGDI1 Through Aos1 and Uba2 Subunits, and then Regulates RhoGDI1 Stability and Cell Proliferation.

PURPOSE: Ang II regulates RhoGDI1 stability and cell proliferation via SUMOylation. However, how Ang II regulates RhoGDI1 SUMOylation remains unknown. In this study, we focused on revealing the effects of E1 subunits (Aos1 and Uba2) on RhoGDI1 SUMOylation in HA-VSMC proliferation. METHODS: The expressions of Aos1, Uba2, and SUMO1 were suppressed by siRNA transfection. HA-VSMCs were treated with Ang II (100 nM) for 24 h. RhoGDI1 SUMOylation and ubiquitination were checked by co-immunoprecipitation. Cell proliferation was detected by EdU assay. RESULTS: Uba2 or Aos1 suppression significantly inhibited Ang II-induced SUMO2/3 modification of RhoGDI1 and cell proliferation, while not affecting SUMO1 modification of RhoGDI1. In addition, Uba2 or Aos1 suppression promoted RhoGDI1 ubiquitination and degradation. These indicate that both Uba2 and Aos1 are necessary for SUMO2/3 modification of RhoGDI1 that participates in cell proliferation by regulating RhoGDI1 ubiquitination and stability. Moreover, SUMO1 suppression did not affect RhoGDI1 ubiquitination and degradation and cell proliferation in Ang II-induced VSMCs, suggesting that SUMO1 modification does not participate in RhoGDI1 stability and cell proliferation. CONCLUSION: This study reveals the differences between SUMO2/3 and SUMO1 modification in regulating RhoGDI1 stability and Ang II-mediated cell proliferation. Schematic summary of roles of SUMO1 and SUMO2/3 modification of RhoGDI1 in regulating RhoGDI1 stability and cell proliferation in Ang II-treated HA-VSMCs.

The Nrf2 inhibitor brusatol has a protective role in a rat model of oxygen-induced retinopathy of prematurity.

Nuclear factor-erythroid 2-related factor 2 (Nrf2) has been testified to be involved in the development of retinopathy of prematurity (ROP), which can cause childhood visual impairment. Whether brusatol, an Nrf2 inhibitor, could be utilized to treat ROP was unknown. The oxygen-induced retinopathy rat model was established to mimic ROP, which was further intravitreal administrated with brusatol. Vessel morphology and microglial activation in the retina were assessed with histology analysis. The relative expression levels of angiogenesis and inflammation-related molecules were detected with Western blot and real-time polymerase chain reaction methods. Intravitreal brusatol administration could alleviate both angiogenesis and microgliosis induced by hyperoxia, along with down-regulation of vascular endothelial growth factor, vascular endothelial growth factor receptor (VEGFR)-1, VEGFR-2, cluster of differentiation molecule 11B, tumor necrosis factor alpha, inducible nitric oxide synthase, glial fibrillary acidic protein, and IBA-1 expression. It was further revealed that Nrf2 and heme oxygenease-1 were diminished by brusatol administration. The results demonstrate the potential of intravitreal brusatol deliver to treat ROP with down-regulation of angiogenesis and microgliosis.

A high-throughput and low-cost maize ear traits scorer.

In this study, based on automatic control and image processing, a high-throughput and low-cost maize ear traits scorer (METS) was developed for the automatic measurement of 34 maize ear traits. In total, 813 maize ears were measured using METS, and the results showed that the square of the correlation coefficient (R2) of the manual measurements versus the automatic measurements for ear length, ear diameter, and kernel thickness were 0.96, 0.79, and 0.85, respectively. These maize ear traits could be used to classify the type, and the results showed that the classification accuracy of the support vector machine (SVM) model for the test set was better than that of the random forest (RF) model. In addition, the general applicability of the image analysis pipeline was also demonstrated on other independent maize ear phenotyping platforms. In conclusion, equipped with image processing and automatic control technologies, we have developed a high-throughput method for maize ear scoring, which could be popularized in maize functional genetics, genomics, and breeding applications. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01205-4.

Tetrahydroxystilbene glucoside protects against LPS-induced endothelial dysfunction via inhibiting RhoA/ROCK signaling and F-actin remodeling.

We analyzed the role of the RhoA/ROCK pathway in regulating endothelial dysfunction triggered by LPS and the protective effects of TSG (2, 3, 5, 4'-tetrahydroxystilbene-2-O-ß-D-glucoside). Human umbilical vein endothelial cells (HUVECs) were treated with LPS at different concentrations or at different time points. Cells were also pretreated with 30 µM ROCK inhibitor Y27632 for 30 min or different concentrations of TSG for 24 h and then were incubated with 100 µg/ml LPS for another 24 h. The results showed that LPS treatment significantly reduced endothelial cell viability, increased LDH release, and promoted cell necrosis in a dose- and time-dependent manner, which was dramatically inhibited by TSG pretreatment. Furthermore, LPS induction significantly enhanced the expression of RhoA, ROCK1, and ROCK2 and the activation of ROCK; these effects were reduced by TSG pretreatment. The suppression of either RhoA or ROCK significantly improved LPS-induced endothelial cell viability, and reduced cell necrosis and LDH release. In addition, LPS treatment promoted F-actin skeleton rearrangement and contraction ring formation around the plasma membrane, which was greatly inhibited by the suppression of the RhoA/ROCK pathway or TSG pretreatment. In conclusion, TSG may inhibit F-actin cytoskeletal remodeling by blocking RhoA/ROCK signaling and thus reduce LPS-induced endothelial cell toxicity.

RhoA/ROCK Pathway Activation is Regulated by AT1 Receptor and Participates in Smooth Muscle Migration and Dedifferentiation via Promoting Actin Cytoskeleton Polymerization.

BACKGROUND: In this study, we investigated the mechanism of Rho GTPases signaling on Ang II-mediated cell migration and dedifferentiation in human aortic vascular smooth muscle cells (HA-VSMCs) and an Ang II-infusion mouse model. METHODS: Cells were pretreated with different inhibitors or Ang II. Cell migration was detected by Wound healing and Transwell assay. Mice were treated with Ad-RhoA-shRNA virus or Irbesartan or fasudil and then infused with Ang II. RESULTS: Ang II treatment induced HA-VSMCs migration in a dose- and time-dependent manner and reduced the expression of VSMC contractile proteins. These effects were significantly suppressed by the inhibition of Ang II type 1 receptor (AT1 receptor), RhoA, and Rho-associated kinase (ROCK). Furthermore, Ang II treatment promoted the activation of RhoA and ROCK, which was reduced by AT1 receptor inhibition. Meanwhile, Ang II treatment induced F-actin polymerization, which was inhibited after ROCK inhibition. In mice, Ang II infusion increased VSMC migration into the neointima and reduced VSMC differentiation proteins levels, and these effects were shown to be dependent on AT1 receptor and RhoA/ROCK pathway. CONCLUSION: This study reveals a novel mechanism by which Ang II regulates RhoA/ROCK signaling and actin polymerization via AT1 receptor and then affects VSMC dedifferentiation.

PVAT: an important guardian of the cardiovascular system.

Perivascular adipose tissue (PVAT) had long been considered to serve only structural, vessel-supporting purposes, but today PVAT is recognized to be an endocrine organ with important physiological and pathological effects. The expansion of PVAT in vascular homeostasis and vascular disease has attracted much interest. PVAT has been shown to release a wide spectrum of molecules, such as PVAT-derived relaxing factors (PVATRFs) and PVAT-derived contracting factors (PVATCFs). PVAT dysfunction may lead to obesity, atherosclerosis, and other cardiovascular diseases. This review describes recent advances in our understanding of PVAT's important effects on the cardiovascular system.