Rho-associated coiled-coil-forming kinases (ROCKs): potential targets for the treatment of atherosclerosis and vascular disease

Therapeutic Efficacy of Small Extracellular Vesicles Loaded with ROCK Inhibitor in Parkinson's Disease

Background/Objectives: Parkinson's disease (PD) is a rapidly growing neurological disorder in the developed world, affecting millions over the age of 60. The decline in motor functions occurs due to a progressive loss of midbrain dopaminergic neurons, resulting in lowered dopamine levels and impaired muscle function. Studies show defective mitochondrial autophagy (or "mitophagy") links to PD. Rho-associated coiled-coil containing protein kinases (ROCK) 1 and ROCK2 are serine/threonine kinases, and their inhibition can enhance neuroprotection in PD by promoting mitophagy. Methods: We examine the effects of ROCK inhibitor SR3677, delivered via macrophage-derived small extracellular vesicles (sEVs) to Parkin Q311X(A) PD mouse models. sEVs with SR3677, administered intranasally, increased mitophagy gene expression, reduced inflammatory factors, and elevated dopamine levels in brain tissues. Results: ROCK2 expression decreased, showing the drug's inhibitory effect. sEV-SR3677 treatment was more effective than treatment with the drug alone, although sham EVs showed lower effects. This suggests that EV-SR3677 not only activates mitochondrial processes but also promotes the degradation of damaged mitochondria through autophagy. Mitochondrial functional assays and oxygen consumption in ex vivo glial cultures revealed that sEV-SR3677 significantly improved mitochondrial respiration compared to that in untreated or SR3677-only treated cells. Conclusion: We demonstrated the efficacy of ROCK2 inhibition on mitochondrial function via sEV-SR3677 in the PD mouse model, necessitating further studies to explore design challenges and mechanisms of sEV-SR3677 as mitochondria-targeted therapy for PD.

Preconditioning with Ginsenoside Rg3 mitigates cardiac injury induced by high-altitude hypobaric hypoxia exposure in mice by suppressing ferroptosis through inhibition of the RhoA/ROCK signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ginseng has historically been utilized as a conventional herbal remedy and dietary supplement to enhance physical stamina and alleviate fatigue. The primary active component of Ginseng, Ginsenoside Rg3 (GS-Rg3), possesses diverse pharmacological properties including immune modulation and anti-inflammatory effects. Furthermore, GS-Rg3 has demonstrated efficacy in mitigating tissue and organ damage associated with metabolic disorders such as hypertension, hyperglycemia, and hyperlipidemia. Nevertheless, its potential impact on high-altitude cardiac injury (HACI) remains insufficiently explored.

AIM OF THE STUDY

The aim of this study was to examine the potential cardioprotective effects of Ginsenoside Rg3, and to investigate how Ginsenoside Rg3 preconditioning can enhance high-altitude cardiac injury by inhibiting the RhoA/ROCK pathway and ferroptosis in cardiac tissue. The findings of this study may contribute to the development of novel therapeutic strategies using traditional Chinese medicine for high-altitude cardiac injury, based on experimental evidence.

MATERIALS AND METHODS

A hypobaric hypoxia chamber was employed to simulate hypobaric hypoxia conditions equivalent to an altitude of 6000 m. Through a randomization process, groups of six male mice were assigned to receive either saline, Ginsenoside Rg3 at doses of 15 mg/kg or 30 mg/kg, or lysophosphatidic acid (LPA) at 1 mg/kg. The impact of Ginsenoside Rg3 on high altitude-induced arrhythmias was evaluated using electrocardiography. Cardiac pathology sections stained with hematoxylin and eosin were evaluated for damage, with the extent of cardiomyocyte damage observed via transmission electron microscopy. The impact of Ginsenoside Rg3 on high-altitude cardiac injury was investigated through analysis of serum biomarkers for cardiac injury (CK-MB, BNP), inflammatory cytokines (TNF, IL-6, IL-1β), reactive oxygen species (ROS) and glutathione (GSH). The expression levels of hypoxia and hypoxia-related proteins in myocardial tissues from each experimental group were assessed using Western blot analysis. Following a review of the existing literature, the traditional regulatory mechanisms of ferroptosis were examined. Immunofluorescence staining of cardiac tissues and Western blotting techniques were utilized to investigate the impact of Ginsenoside Rg3 on cardiomyocyte ferroptosis through the RhoA/ROCK signaling pathway under conditions of hypobaric hypoxia exposure.

RESULTS

Pre-treatment with Ginsenoside Rg3 improved high altitude-induced arrhythmias, reduced cardiomyocyte damage, decreased cardiac injury biomarkers and inflammatory cytokines, and lowered the expression of hypoxia-related proteins in myocardial tissues. Both Western blotting and immunofluorescence staining of cardiac tissues demonstrated that exposure to high-altitude hypobaric hypoxia results in elevated expression of ferroptosis and proteins related to the RhoA/ROCK pathway. Experimental validation corroborated that the role of the RhoA/ROCK signaling pathway in mediating ferroptosis.

CONCLUSIONS

The findings of our study suggest that preconditioning with Ginsenoside Rg3 may attenuate cardiac injury caused by high-altitude hypobaric hypoxia exposure in mice by inhibiting ferroptosis through the suppression of the RhoA/ROCK signaling pathway. These findings contribute to the current knowledge of Ginsenoside Rg3 and high-altitude cardiac injury, suggesting that Ginsenoside Rg3 shows potential as a therapeutic agent for high-altitude cardiac injury.

Novel insights into the ROCK-JAK-STAT signaling pathway in upper respiratory tract infections and neurodegenerative diseases

Acute upper respiratory tract infections are a major public health issue, with uncontrolled inflammation triggered by upper respiratory viruses being a significant cause of patient deterioration or death. This study focuses on the Janus kinase-signal transducer and activator of transcription Rho-associated coiled-coil containing protein kinase (JAK-STAT-ROCK) signaling pathway, providing an in-depth analysis of the interplay between uncontrolled inflammation after upper respiratory tract infections and the development of neurodegenerative diseases. It offers a conceptual framework for understanding the lung-brain-related immune responses and potential interactions. The relationship between the ROCK-JAK-STAT signaling pathway and inflammatory immunity is a complex and multi-layered research area and exploring potential common targets could open new avenues for the prevention and treatment of related inflammation.

Heteryunine A, an amidated tryptophan-catechin-spiroketal hybrid with antifibrotic activity from Heterosmilax yunnanensis

An unprecedented spiro-C-glycoside adduct, heteryunine A (1), along with two uncommon alkaloids featuring a 2,3-diketopiperazine skeleton, heterpyrazines A (2) and B (3), were discovered in the roots of Heterosmilax yunnanensis. The detailed spectroscopic analysis helped to clarify the planar structures of these compounds. Compound 1, containing 7 chiral centers, features a catechin fused with a spiroketal and connects with a tryptophan derivative by a CC bond. Its complex absolute configuration was elucidated by rotating frame overhauser enhancement spectroscopy (ROESY), specific rotation, and the 13C nuclear magnetic resonance (NMR) and electronic circular dichroism (ECD) calculation. The possible biosynthetic routes for 1 were deduced. Compounds 1 and 2 showed significant antifibrotic effects and further research revealed that they inhibited the activation, migration and proliferation of hepatic stellate cells (HSCs) through suppressing the activity of Ras homolog family member A (RhoA).

How Protein Depletion Balances Thrombosis and Bleeding Risk in the Context of Platelet's Activatory and Negative Signaling

Platelets are small cell fragments that play a crucial role in hemostasis, requiring fast response times and fine signaling pathway regulation. For this regulation, platelets require a balance between two pathway types: the activatory and negative signaling pathways. Activatory signaling mediators are positive responses that enhance stimuli initiated by a receptor in the platelet membrane. Negative signaling regulates and controls the responses downstream of the same receptors to roll back or even avoid spontaneous thrombotic events. Several blood-related pathologies can be observed when these processes are unregulated, such as massive bleeding in activatory signaling inhibition or thrombotic events for negative signaling inhibition. The study of each protein and metabolite in isolation does not help to understand the role of the protein or how it can be contrasted; however, understanding the balance between active and negative signaling could help develop effective therapies to prevent thrombotic events and bleeding disorders.

Myosin light chain phosphatase is a downstream target of Rho-kinase in endothelin-1-induced transactivation of the TGF-β receptor

BACKGROUND

Rho-kinase (ROCK) regulates actomyosin contraction, coronary vasospasm, and cytoskeleton dynamics. ROCK and of NADPH oxidase (NOX) play an essential role in cardiovascular disease and proteoglycan synthesis, which promotes atherosclerosis by trapping low density lipoprotein. ROCK is activated by endothelin-1 (ET1) and transactivates the transforming growth factor beta receptor (TGFβR1), intensifying Smad signaling and proteoglycan production. This study aimed to identify the role of myosin light chain phosphatase (MLCP) as a downstream target of ROCK in TβR1 transactivation.

METHODS

Vascular smooth muscle cells were treated with ET1 and inhibitors of ROCK and MLCP were added. The phosphorylation levels of Smad2C, myosin light chain (MLC), and MLCP were monitored by western blot, and the mRNA expression of chondroitin 4-O-sulfotransferase 1 (C4ST1) was assessed by quantitative real-time PCR.

RESULTS

We examined ROCK's role in ET1-induced TGFβR1 activation. ROCK phosphorylated MLCP at the MYPT1 T853 residue, blocked by the ROCK inhibitor Y27632. ROCK also increased MLC phosphorylation and actomyosin contraction in response to ET1, enhanced by the phosphatase inhibitor Calyculin A. Calyculin A also increased C4ST1 expression, GAG-chain synthesizing enzymes.

CONCLUSIONS

This work suggests that ROCK is involved in ET1-mediated TβR1 activation through increased MLCP phosphorylation, which leads to Smad2C phosphorylation and stimulates C4ST1 expression.

β-Adrenoceptors regulate urothelial inflammation and zonula occludens in the bladder outlet obstruction model

BACKGROUND

The purpose of this study was to evaluate the effects of β-adrenoceptors (ADRBs) on the urothelial inflammation and zonula occludens (ZO) in a rat PBOO model and in an in vitro model.

METHODS

The PBOO model was established by ligating the bladder neck of rats. Twenty rats were divided into 4 groups: sham operation, PBOO + normal saline, PBOO + ADRB2 agonist, PBOO + ADRB3 agonist. PBOO rats were with treated with ADRBs agonists for 3 weeks. Human urothelial cells (HUCs) were subjected to ADRBs agonist treatment or hydrostatic pressure in an in vitro model.

RESULTS

In the PBOO group, there was a significant increase in the expression of MCP-1, IL-6 and RANTES compared to the sham group. By contrast, there was a post-PBOO decline in the expression of ZO-1 and ZO-2 in the urothelium. ADRB2 or ADRB3 agonists exhibited downregulated inflammatory cytokine expression and increased ZO expression in the PBOO model. The regulation of inflammation and ZO by ADRB2 and ADRB3 agonists in an in vitro model was found consistent with that in the PBOO model. Moreover, RhoA and ROCK inhibitors suppressed the expression of hydrostatic pressure-induced inflammatory cytokines. Additionally, RhoA agonist reversed the inhibitory effect of ADRBs agonists on the inflammatory secretion from HUCs.

CONCLUSIONS

ADRB2 and ADRB3 agonists increased ZO protein expression in HUCs in a rat PBOO model and in an in vitro model. Furthermore, ADRB2 and ADRB3 agonists inhibited the secretion of inflammatory cytokines from HUCs by regulating the RhoA/ROCK signaling pathways.

Smoking cessation and vascular endothelial function

Smoking is associated with vascular endothelial dysfunction. It is thought that smoking impairs vascular endothelial function through a decrease in nitric oxide bioavailability induced by activation of oxidative stress and inflammation. Endothelial dysfunction can be improved or augmented by appropriate interventions including pharmacotherapy, administration of supplements and lifestyle modifications. Although there have not been many studies, the effects of smoking cessation on endothelial function have been shown. In those studies, it was shown that smoking cessation does not always have a positive effect on vascular endothelial function. In this review, I will focus on the role of smoking in endothelial function and the effects of smoking cessation on endothelial function. Smoking impairs vascular endothelial function and leads to atherosclerosis. Smoking cessation is expected to improve vascular endothelial function. Effects of smoking cessation on endothelial function are not always consistent. Further studies are needed to determine whether smoking cessation directly improves endothelial function. NO indicates nitric oxide.

Roles of salt‑inducible kinases in cancer (Review)

Salt inducible kinases (SIKs) with three subtypes SIK1, SIK2 and SIK3, belong to the AMP‑activated protein kinase family. They are expressed ubiquitously in humans. Under normal circumstances, SIK1 regulates adrenocortical function in response to high salt or adrenocorticotropic hormone stimulation, SIK2 is involved in cell metabolism, controlling insulin signaling and gluconeogenesis and SIK3 coordinates with the mTOR complex, promoting cancer. The dysregulation of SIKs has been widely detected in various types of cancers. Based on most of the existing studies, SIK1 is mostly considered a tumor inhibitor, SIK2 and SIK3 are usually associated with tumor promotion. However, the functions of SIKs have shown contradictory in certain tumors, suggesting that SIKs cannot be simply classified as oncogenes or tumor suppressor genes. The present review provided a comprehensive summary of the roles of SIKs in the initiation and progression of different cancers, aiming to elucidate their clinical value and discuss potential strategies for targeting SIKs in cancer therapy.

ZXDC enhances cervical cancer metastasis through IGF2BP3-mediated activation of RhoA/ROCK signaling

Metastasis in cervical cancer (CC) has a significant negative impact on patient survival, highlighting the urgent need for investigation in this area. In this study, we identified significant overexpression of zinc finger, X-linked, duplicated family member C (ZXDC) in CC tissue with metastasis, which correlates with poor outcomes for CC patients. We observed that overexpression of ZXDC promotes, while silencing of ZXDC inhibits the metastasis of CC cells both in vitro and in vivo. Additionally, our research demonstrated that ZXDC activated RhoA/ROCK signaling pathway, leading to enhanced cytoskeleton remodeling in CC cells. Besides, we found that IGF2BP3 plays an essential role in the activation of ZXDC on the RhoA/ROCK signaling pathway by stabilizing RhoA mRNA. These findings reveal a mechanism whereby ZXDC promotes the cervical cancer metastasis by targeting IGF2BP3/RhoA/ROCK pathway.

Mitochondria spatially and temporally modulate VSMC phenotypes via interacting with cytoskeleton in cardiovascular diseases

Cardiovascular diseases caused by atherosclerosis (AS) seriously endanger human health, which is closely related to vascular smooth muscle cell (VSMC) phenotypes. VSMC phenotypic transformation is marked by the alteration of phenotypic marker expression and cellular behaviour. Intriguingly, the mitochondrial metabolism and dynamics altered during VSMC phenotypic transformation. Firstly, this review combs VSMC mitochondrial metabolism in three aspects: mitochondrial ROS generation, mutated mitochondrial DNA (mtDNA) and calcium metabolism respectively. Secondly, we summarized the role of mitochondrial dynamics in regulating VSMC phenotypes. We further emphasized the association between mitochondria and cytoskelton via presenting cytoskeletal support during mitochondrial dynamics process, and discussed its impact on their respective dynamics. Finally, considering that both mitochondria and cytoskeleton are mechano-sensitive organelles, we demonstrated their direct and indirect interaction under extracellular mechanical stimuli through several mechano-sensitive signaling pathways. We additionally discussed related researches in other cell types in order to inspire deeper thinking and reasonable speculation of potential regulatory mechanism in VSMC phenotypic transformation.

DNMT1 involved in the analgesic effect of folic acid on gastric hypersensitivity through downregulating ASIC1 in adult offspring rats with prenatal maternal stress

AIMS

Gastric hypersensitivity (GHS) is a characteristic pathogenesis of functional dyspepsia (FD). DNA methyltransferase 1 (DNMT1) and acid-sensing ion channel 1 (ASIC1) are associated with GHS induced by prenatal maternal stress (PMS). The aim of this study was to investigate the mechanism of DNMT1 mediating the analgesic effect of folic acid (FA) on PMS-induced GHS.

METHODS

GHS was quantified by electromyogram recordings. The expression of DNMT1, DNMT3a, DNMT3b, and ASIC1 were detected by western blot, RT-PCR, and double-immunofluorescence. Neuronal excitability and proton-elicited currents of dorsal root ganglion (DRG) neurons were determined by whole-cell patch clamp recordings.

RESULTS

The expression of DNMT1, but not DNMT3a or DNMT3b, was decreased in DRGs of PMS rats. FA alleviated PMS-induced GHS and hyperexcitability of DRG neurons. FA also increased DNMT1 and decreased ASIC1 expression and sensitivity. Intrathecal injection of DNMT1 inhibitor DC-517 attenuated the effect of FA on GHS alleviation and ASIC1 downregulation. Overexpression of DNMT1 with lentivirus not only rescued ASIC1 upregulation and hypersensitivity, but also alleviated GHS and hyperexcitability of DRG neurons induced by PMS.

CONCLUSIONS

These results indicate that increased DNMT1 contributes to the analgesic effect of FA on PMS-induced GHS by reducing ASIC1 expression and sensitivity.

Intracellular Vimentin Regulates the Formation of Classical Swine Fever Virus Replication Complex through Interaction with NS5A Protein

Vimentin (VIM), an indispensable protein, is responsible for the formation of intermediate filament structures within cells and plays a crucial role in viral infections. However, the precise role of VIM in classical swine fever virus (CSFV) infection remains unclear. Herein, we systematically investigated the function of VIM in CSFV replication. We demonstrated that both knockdown and overexpression of VIM affected CSFV replication. Furthermore, we observed by confocal microscopy the rearrangement of cellular VIM into a cage-like structure during CSFV infection. Three-dimensional (3D) imaging indicated that the cage-like structures were localized in the endoplasmic reticulum (ER) and ringed around the double-stranded RNA (dsRNA), thereby suggesting that VIM was associated with the formation of the viral replication complex (VRC). Mechanistically, phosphorylation of VIM at serine 72 (Ser72), regulated by the RhoA/ROCK signaling pathway, induced VIM rearrangement upon CSFV infection. Confocal microscopy and coimmunoprecipitation assays revealed that VIM colocalized and interacted with CSFV NS5A. Structurally, it was determined that amino acids 96 to 407 of VIM and amino acids 251 to 416 of NS5A were the respective important domains for this interaction. Importantly, both VIM knockdown and disruption of VIM rearrangement inhibited the localization of NS5A in the ER, implying that VIM rearrangement recruited NS5A to the ER for VRC formation. Collectively, our results suggest that VIM recruits NS5A to form a stable VRC that is protected by the cage-like structure formed by VIM rearrangement, ultimately leading to enhanced virus replication. These findings highlight the critical role of VIM in the formation and stabilization of VRC, which provides alternative strategies for the development of antiviral drugs. IMPORTANCE Classical swine fever (CSF), caused by classical swine fever virus (CSFV), is a highly infectious disease that poses a significant threat to the global pig industry. Therefore, gaining insights into the virus and its interaction with host cells is crucial for developing effective antiviral measures and controlling the spread of CSF. Previous studies have shown that CSFV infection induces rearrangement of the endoplasmic reticulum, leading to the formation of small vesicular organelles containing nonstructural protein and double-stranded RNA of CSFV, as well as some host factors. These organelles then assemble into viral replication complexes (VRCs). In this study, we have discovered that VIM recruited CSFV NS5A to form a stable VRC that was protected by a cage-like structure formed by rearranged VIM. This enhanced viral replication. Our findings not only shed light on the molecular mechanism of CSFV replication but also offer new insights into the development of antiviral strategies for controlling CSFV.

ROCK inhibitors in ophthalmology: A critical review of the existing clinical evidence

Rho kinase (ROCK) inhibitors have emerged as a key therapeutic class of interest in ophthalmology over the last decade. Promising in vitro studies laid the foundations for the development of novel therapeutic agents that target the ROCK signalling pathway in ocular disease, with subsequent clinical trials supporting their use. Corneal endothelial disease, glaucoma, and vitreoretinal disease are the major pathologies in which ROCK inhibitors have been investigated to date. Ripasudil and netarsudil represent the current leaders in this pharmaceutical group, having been extensively validated and approved for use in glaucoma in some countries. Less substantial evidence exists for fasudil in ophthalmic use. ROCK inhibitors are also increasingly used in cultured endothelial cell grafting and as an adjunct to aid in endothelial cell migration and replication in Descemet's stripping procedures or Descemet's membrane injuries. This review has synthesised both established and emerging research to provide a practical guide to prescribing in this drug class. Drug efficacies, side effect profiles, and the demographic and clinical characteristics of appropriate drug candidates are discussed.

Application and Study of ROCK Inhibitors in Pulmonary Fibrosis: Recent Developments and Future Perspectives

Rho-associated coiled-coil-containing kinases (ROCKs), serine/threonine protein kinases, were initially identified as downstream targets of the small GTP-binding protein Rho. Pulmonary fibrosis (PF) is a lethal disease with limited therapeutic options and a particularly poor prognosis. Interestingly, ROCK activation has been demonstrated in PF patients and in animal PF models, making it a promising target for PF treatment. Many ROCK inhibitors have been discovered, and four of these have been approved for clinical use; however, no ROCK inhibitors are approved for the treatment of PF patients. In this article, we describe ROCK signaling pathways and the structure-activity relationship, potency, selectivity, binding modes, pharmacokinetics (PKs), biological functions, and recently reported inhibitors of ROCKs in the context of PF. We will also focus our attention on the challenges to be addressed when targeting ROCKs and discuss the strategy of ROCK inhibitor use in the treatment of PF.

Evaluation of toxicity of polystyrene microplastics under realistic exposure levels in human vascular endothelial EA.hy926 cells

Microplastics (MPs) have emerged as a global concern, with a recent study being the first to detect them in the bloodstream of healthy people. However, precise information regarding the toxic effects of MPs on the human vascular system is currently lacking. In this study, we used human vascular endothelial EA. hy926 cells to examine the toxic potential of polystyrene MPs (PSMPs) under realistic blood concentrations. Our findings indicated that PSMPs can cause oxidative stress by reducing the expression of antioxidants, thereby leading to apoptotic cytotoxicity in EA. hy926 cells. Furthermore, the protective potential of heat shock proteins can be reduced by PSMPs. PSMP-induced apoptosis might also lower the expression of rho-associated protein kinase-1 and nuclear factor-κB expression, thus dampening LRR- and pyrin domain-containing protein 3 in EA. hy926 cells. Moreover, we observed that PSMPs induce vascular barrier dysfunction via the depletion of zonula occludens-1 protein. However, although protein expression of the nuclear hormone receptor 77 was inhibited, no significant increase in ectin-like oxidized low-density lipoprotein receptor-1 was noted in PSMP-treated EA. hy926 cells. These results demonstrate that exposure to PSMPs may not sufficiently increase the risk of developing atherosclerosis. Overall, our research signifies that exposure to realistic blood concentrations of PSMPs is associated with low atherosclerotic cardiovascular risk in humans.

Rho Kinase Inhibitor Y27632 Improves Recovery After Spinal Cord Injury by Shifting Astrocyte Phenotype and Morphology via the ROCK/NF-κB/C3 Pathway

Spinal cord injury (SCI) usually results in loss or reduction in motor and sensory functions. Despite extensive research, no available therapy can restore the lost functions after SCI. Reactive astrocytes play a pivotal role in SCI. Rho kinase inhibitors have also been shown to promote functional recovery of SCI. However, the role of Rho kinase inhibitors in reactive astrocytic phenotype switch within SCI remains largely unexplored. In this study, astrocytes were treated with proinflammatory cytokines and/or the Rho kinase inhibitor Y27632. Concomitantly the phenotype and morphology of astrocytes were examined. Meanwhile, the SCI model of SD rats was established, and nerve functions were evaluated following treatment with Y27632. Subsequently, the number of A1 astrocytes in the injured area was observed and analyzed. Eventually, the expression levels of nuclear factor kappa B (NF-κB), C3, and S100A10 were measured. The present study showed that the Rho kinase inhibitor Y27632 improved functional recovery of SCI and elevated the proliferation and migration abilities of the astrocytes. In addition, Y27632 treatment initiated the switch of astrocytes morphology from a flattened shape to a process-bearing shape and transformed the reactive astrocytes A1 phenotype to an A2 phenotype. More importantly, further investigation suggested that Y27632 was actively involved in promoting the functional recovery of SCI in rats by inhabiting the ROCK/NF-κB/C3 signaling pathway. Together, Rho kinase inhibitor Y27632 effectively promotes the functional recovery of SCI by shifting astrocyte phenotype and morphology. Furthermore, the pro-regeneration event is strongly associated with the ROCK/NF-κB/C3 signal pathway.

Neuroprotective effects of nobiletin on cerebral ischemia/reperfusion injury rats by inhibiting Rho/ROCK signaling pathway

Background

Nobiletin (NOB), an active natural flavonoid component of citrus, is used in Traditional Chinese Medicine for its anti-inflammatory activity, but its efficacy in cerebral ischemia/reperfusion (I/R) injury remains unclear.

Methods

In a middle cerebral artery occlusion (MCAO) rat model, MCAO rats were administered (Sham group and MCAO model group treated with an equal volume of solvent, NOB group treated with 10 or 20 mg/kg NOB) once a day for 7 days before cerebral ischemia and again after reperfusion, 2,3,5-triphenyltetrazolium chloride (TTC) staining was applied to assess the infarct area. Neurological function was evaluated by the modified neurological severity score and Morris water maze. The levels of inflammatory factors, interleukin 6 (IL-6), interleukin 1β (IL-1β) and tumor necrosis factor-α (TNF-α), were examined by enzyme-linked immunosorbent assay (ELISA). Histopathological staining evaluated neuron apoptosis in brain tissue. In an oxygen-glucose deprivation PC12 cell (OGD PC12) model, the proliferation, migration and apoptosis of OGD PC12 cells were detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and cell migration assays and flow cytometry. The gene and protein expression levels of Ras homolog gene family, member A (Rho A), ras-related C3 botulinum toxin substrate 1 (Rac 1), Rho-associated kinase 1 (ROCK 1), ROCK 2 in the Rho/ROCK pathway were measured by Real-time PCR (RT-PCR), immunohistochemistry and western blot.

Results

In rats with cerebral I/R injury, NOB significantly decreased the infarcted area, neuron apoptosis in brain tissue and expressions of IL-6, IL-1β, and TNF-α. It also improved neurological deficits in brain tissue and enhanced learning and memory ability. Further, NOB had a protective effect on OGD PC12 cells, increasing proliferation and migration and decreasing apoptosis. The expressions of Rho A, Rac 1, ROCK 1 and ROCK 2 were high in cerebral I/R injury rats, but were downregulated by NOB in I/R injury rats' brain tissue and OGD PC12 cells.

Conclusions

Nobiletin had a neuroprotective effect in rats with cerebral I/R injury, and its potential mechanism is decreasing neuron apoptosis by inhibiting the Rho/ROCK signaling pathway. These results suggest NOB is a promising neuroprotective agent for patients with cerebral ischemia.

Identification of key differential genes in intimal hyperplasia induced by left carotid artery ligation

Background

Intimal hyperplasia is a common pathological process of restenosis following angioplasty, atherosclerosis, pulmonary hypertension, vein graft stenosis, and other proliferative diseases. This study aims to screen for potential novel gene targets and mechanisms related to vascular intimal hyperplasia through an integrated microarray analysis of the Gene Expression Omnibus Database (GEO) database.

Material and Methods

The gene expression profile of the GSE56143 dataset was downloaded from the Gene Expression Omnibus database. Functional enrichment analysis, protein-protein interaction (PPI) network analysis, and the transcription factor (TF)-target gene regulatory network were used to reveal the biological functions of differential genes (DEGs). Furthermore, the expression levels of the top 10 key DEGs were verified at the mRNA and protein level in the carotid artery 7 days after ligation.

Results

A total of 373 DEGs (199 upregulated DEGs and 174 downregulated DEGs) were screened. These DEGs were significantly enriched in biological processes, including immune system process, cell adhesion, and several pathways, which were mainly associated with cell adhesion molecules and the regulation of the actin cytoskeleton. The top 10 key DEGs (Ptprc, Fn1, Tyrobp, Emr1, Itgb2, Itgax, CD44, Ctss, Ly86, and Aif1) acted as key genes in the PPI network. The verification of these key DEGs at the mRNA and protein levels was consistent with the results of the above-mentioned bioinformatics analysis.

Conclusion

The present study identified key genes and pathways involved in intimal hyperplasia induced by carotid artery ligation. These results improved our understanding of the mechanisms underlying the development of intimal hyperplasia and provided candidate targets.

Belumosudil with ROCK-2 inhibition: chemical and therapeutic development to FDA approval for the treatment of chronic graft-versus-host disease

Belumosudil (BLM) is a ROCK inhibitor that has been firstly developed by Surface Logix, later acquired by Kadmon Pharmaceuticals for the treatment of chronic graft-versus-host disease (cGVHD), Psoriasis Vulgaris (PV), idiopathic pulmonary fibrosis (IPF), hepatic impairment (HI), diffuse cutaneous systemic sclerosis (dcSSc). BLM received a breakthrough therapy designation and priority review from the FDA, which reviewed the NDA under the real-time oncology review (RTOR) pilot programme and approved it six weeks ahead of the PDUFA deadline of August 30, 2021. On July 16^th, 2021, The USFDA authorized BLM under the brand name REZUROCK^TM for the treatment of cGVHD in adults and pediatric patients aged ≥ 12 years after the failure of at least two prior lines of systemic therapy. It has been granted orphan drug status by the FDA on August 9, 2020, for the treatment of systemic sclerosis. The European Union (EU) granted Quality Regulatory Clinical Ireland Limited, Ireland, orphan drug status for BLM (KD025) for the treatment of cGVHD on October 17, 2019. BLM is under regulatory assessment by Therapeutic Good Administration (TGA) Australia, Health Canada, MHRA (UK), and The Swiss Agency for Therapeutic Products (Swissmedic), Switzerland for cGVHD. A clinical trial is ongoing in the United States for cutaneous systemic sclerosis. This review article summarizes the milestones in the development of BLM chemistry, Chemical synthesis and development, mechanism of action, pharmacokinetics (PK), pharmacodynamics (PD), adverse effects, regulatory status, and ongoing clinical trials (CT) of BLM.

SIK2 promotes ovarian cancer cell motility and metastasis by phosphorylating MYLK

Salt‐inducible kinase 2 (SIK2; also known as serine/threonine‐protein kinase SIK2) is overexpressed in several cancers and has been implicated in cancer progression. However, the mechanisms by which SIK2 regulates cancer cell motility, migration and metastasis in ovarian cancer have not been fully discovered. Here, we identify that SIK2 promotes ovarian cancer cell motility, migration and metastasis in vitro and in vivo. Mechanistically, SIK2 regulated cancer cell motility and migration by myosin light chain kinase, smooth muscle (MYLK)‐meditated phosphorylation of myosin light chain 2 (MYL2). SIK2 directly phosphorylated MYLK at Ser343 and activated its downstream effector MYL2, promoting ovarian cancer cell motility and metastasis. In addition, we found that adipocytes induced SIK2 phosphorylation at Ser358 and MYLK phosphorylation at Ser343, enhancing ovarian cancer cell motility. Moreover, SIK2 protein expression was positively correlated with the expression of MYLK‐pS343 in ovarian cancer cell lines and tissues. The co‐expression of SIK2 and MYLK‐pS343 was associated with reduced median overall survival in human ovarian cancer samples. Taken together, SIK2 positively regulates ovarian cancer motility, migration and metastasis, suggesting that SIK2 is a potential candidate for ovarian cancer treatment.

Status of Rho kinase inhibitors in glaucoma therapeutics-an overview

Medical management remains the cornerstone of glaucoma management despite advances in the surgical or laser procedures. After a leap of almost two decades of the advent of prostaglandin analogues, recently a new class of drug, Rho kinase (ROCK) inhibitors, has come to limelight because of their varied therapeutic potential in different clinical conditions of eye, especially glaucoma. Their efficacy of lowering intraocular pressure (IOP) by virtue of an entirely different mechanism of decreasing outflow resistance has ignited a series of clinical trials evaluating their potential as monotherapy or as adjunct to existing antiglaucoma medications, and three of them ripasudil, netarsudil and roclatan have even been approved for clinical use in the recent past. There are evidences suggesting their beneficial effects in glaucoma patients even via non-IOP-dependent mechanisms like neuroprotection by improving blood flow to the optic nerve and increasing ganglion cell survival. They can even act as antifibrotic agents and reduce bleb scarring after glaucoma surgery. Hence, their effective role in glaucomatous optic neuropathy is multifaceted primary being improved drainage through the conventional pathway. On the other hand, certain local adverse effects like conjunctival hyperaemia have been reported in substantial proportion of patients, while some others like blepharitis, subconjunctival haemorrhages and cornea verticillata constitute less common side effects. The purpose of this review is to summarize the discovery, evolution and recent update of clinical trials on Rho kinase inhibitors as antiglaucoma medicine and to delineate their role in existing management protocol.

Abnormal TPM2 expression is involved in regulation of atherosclerosis progression via mediating RhoA signaling in vitro

Introduction

Ox-LDL (oxidized low-density lipoprotein)-induced endothelial cell injury and dysfunction of vascular smooth muscle cells play critical roles in the development of atherosclerosis (AS). Tropomyosin 2 (TPM2) has been implicated in cardiac diseases, but its critical role and regulatory mechanism in AS progression have not yet been elucidated.

Material and methods

The expression of TPM2 was investigated in AS tissues. Ox-LDL was used to construct an AS in vitro model based on endothelial and vascular smooth muscle cells (HAECs and VSMCs). An overexpression assay was performed to evaluate the role of TPM2 in AS. Meanwhile, the involvement of the RhoA pathway in TPM2-mediated AS progression was evaluated using narciclasine.

Results

Tropomyosin 2 was dramatically upregulated in both AS tissues and ox-LDL-induced HAECs. Overexpression of TPM2 attenuated ox-LDL-stimulated cell growth depression, inflammatory and adhesive responses in HAECs, as well as oxidative stress and mitochondrial dysfunction. Additionally, VSMCs, impacted by TPM2-overexpressed HAECs, showed alleviated cellular processes which were abnormally activated by ox-LDL. Furthermore, depressed activation of the RhoA pathway was found in TPM2-overexpressed HAECs and activating the signaling rescued these effects of TPM2 exerted on ox-LDL-stimulated HAECs and VSMCs.

Conclusions

TPM2 had an advantageous impact on ox-LDL-induced AS progression in vitro by mediating the RhoA pathway. This evidence might contribute to the therapy of AS.

Functional Role of Non-Muscle Myosin II in Microglia: An Updated Review

Myosins are a remarkable superfamily of actin-based motor proteins that use the energy derived from ATP hydrolysis to translocate actin filaments and to produce force. Myosins are abundant in different types of tissues and involved in a large variety of cellular functions. Several classes of the myosin superfamily are expressed in the nervous system; among them, non-muscle myosin II (NM II) is expressed in both neurons and non-neuronal brain cells, such as astrocytes, oligodendrocytes, endothelial cells, and microglia. In the nervous system, NM II modulates a variety of functions, such as vesicle transport, phagocytosis, cell migration, cell adhesion and morphology, secretion, transcription, and cytokinesis, as well as playing key roles during brain development, inflammation, repair, and myelination functions. In this review, we will provide a brief overview of recent emerging roles of NM II in resting and activated microglia cells, the principal regulators of immune processes in the central nervous system (CNS) in both physiological and pathological conditions. When stimulated, microglial cells react and produce a number of mediators, such as pro-inflammatory cytokines, free radicals, and nitric oxide, that enhance inflammation and contribute to neurodegenerative diseases. Inhibition of NM II could be a new therapeutic target to treat or to prevent CNS diseases.

Systematic bioinformatic analysis of nutrigenomic data of flavanols in cell models of cardiometabolic disease

Flavanol intake positively influences several cardiometabolic risk factors in humans. However, the specific molecular mechanisms of action of flavanols, in terms of gene regulation, in the cell types relevant to cardiometabolic disease have never been systematically addressed. On this basis, we conducted a systematic literature review and a comprehensive bioinformatic analysis of genes whose expression is affected by flavanols in cells defining cardiometabolic health: hepatocytes, adipocytes, endothelial cells, smooth muscle cells and immune cells. A systematic literature search was performed using the following pre-defined criteria: treatment with pure compounds and metabolites (no extracts) at low concentrations that are close to their plasma concentrations. Differentially expressed genes were analyzed using bioinformatics tools to identify gene ontologies, networks, cellular pathways and interactions, as well as transcriptional and post-transcriptional regulators. The systematic literature search identified 54 differentially expressed genes at the mRNA level in in vitro models of cardiometabolic disease exposed to flavanols and their metabolites. Global bioinformatic analysis revealed that these genes are predominantly involved in inflammation, leukocyte adhesion and transendothelial migration, and lipid metabolism. We observed that, although the investigated cells responded differentially to flavanol exposure, the involvement of anti-inflammatory responses is a common mechanism of flavanol action. We also identified potential transcriptional regulators of gene expression: transcriptional factors, such as GATA2, NFKB1, FOXC1 or PPARG, and post-transcriptional regulators: miRNAs, such as mir-335-5p, let-7b-5p, mir-26b-5p or mir-16-5p. In parallel, we analyzed the nutrigenomic effects of flavanols in intestinal cells and demonstrated their predominant involvement in the metabolism of circulating lipoproteins. In conclusion, the results of this systematic analysis of the nutrigenomic effects of flavanols provide a more comprehensive picture of their molecular mechanisms of action and will support the future setup of genetic studies to pave the way for individualized dietary recommendations.

Salidroside and isorhamnetin attenuate urotensin II-induced inflammatory response in vivo and in vitro: Involvement in regulating the RhoA/ROCK II pathway

Urotensin II (UII), a vital vasoconstrictor peptide, causes an inflammatory response in the pathogenesis of atherosclerosis. Previous studies have reported that the Ras homolog gene family, member A (RhoA)/Rho kinases (ROCK) pathway modulates the inflammatory response of the atherosclerotic process. However, to the best of our knowledge, whether the RhoA/ROCK pathway mediates the inflammatory effect of UII has not been previously elucidated. Salidroside and isorhamnetin are two early developed antioxidant Tibetan drugs, both displaying cardioprotective effects against atherosclerosis. Therefore, the aim of the present study was to investigate the protective effects of salidroside, isorhamnetin or combination of these two drugs on the UII-induced inflammatory response in vivo (rats) or in vitro [primary vascular smooth muscle cells (VSMCs)], as well as to examine the role of the RhoA/ROCK pathway in these processes. The levels of inflammatory markers were measured via ELISA. The mRNA and protein expression levels of RhoA and ROCK II were detected using reverse transcription-quantitative PCR assay and western blot analysis. It was demonstrated that salidroside, isorhamnetin and both in combination decreased the levels of the serum pro-inflammatory cytokines TNF-α and IL-1β, as well as increased the levels of the anti-inflammatory cytokine IL-10 and macrophage migration inhibitory factor in rats with subacute infusion of UII and in the culture supernatant from primary VSMCs-exposed to UII. Moreover, salidroside, isorhamnetin and both in combination attenuated the mRNA and protein expression levels of RhoA and ROCK II in vivo and in vitro, at concentrations corresponding to human therapeutic blood plasma concentrations. Thus, these drugs could inhibit the RhoA/ROCK II pathway under UII conditions. The combination of salidroside and isorhamnetin did not display a stronger inhibitory effect on the inflammatory response and the RhoA/ROCK II pathway compared with salidroside and isorhamnetin in isolation. Collectively, the results indicated that salidroside, isorhamnetin and both in combination inhibited the RhoA/ROCK II pathway, which then attenuated the inflammatory response under UII-induced conditions, resulting in cardioprotection in atherosclerosis.

Clinical Treatment Options in Scleroderma: Recommendations and Comprehensive Review

There are two major clinical subsets of scleroderma: (i) systemic sclerosis (SSc) is a complex systemic autoimmune disorder characterized by inflammation, vasculopathy, and excessive fibrosis of the skin and multiple internal organs and (ii) localized scleroderma (LoS), also known as morphea, is confined to the skin and/or subcutaneous tissues resulting in collagen deposition and subsequent fibrosis. SSc is rare but is associated with significant morbidity and mortality compared with other rheumatic diseases. Fatal outcomes in SSc often originate from organ complications of the disease, such as lung fibrosis, pulmonary artery hypertension (PAH), and scleroderma renal crisis (SRC). Current treatment modalities in SSc have focused on targeting vascular damage, fibrosis, and regulation of inflammation as well as autoimmune responses. Some drugs previously used in an attempt to suppress fibrosis, like D-penicillamine (D-Pen) or colchicine, have been disappointing in clinical practice despite anecdotal evidence of their advantages. Some canonical medications, including glucocorticoids, immunosuppressants, and vasodilators, have had some success in treating various manifestations in SSc patients. Increasing evidence suggests that some biologic agents targeting collagen, cytokines, and cell surface molecules might have promising therapeutic effects in SSc. In recent years, hematopoietic stem cell transplantation (HSCT), mostly autologous, has made great progress as a promising treatment option in severe and refractory SSc. Due to the complexity and heterogeneity of SSc, there are currently no optimal treatments for all aspects of the disease. As for LoS, local skin-targeted therapy is generally used, including topical application of glucocorticoids or other immunomodulatory ointments and ultraviolet (UV) irradiation. In addition, systemic immunosuppressants are also utilized in several forms of LoS. Here, we comprehensively discuss current treatment options for scleroderma, encompassing old, new, and future potential treatment options. In addition, we summarize data from new clinical trials that have the potential to modify the disease process and improve long-term outcomes in SSc.

Long Noncoding RNAs in the Progression of Atherosclerosis: An Integrated Analysis Based on Competing Endogenous RNA Theory

Long noncoding RNAs (lncRNAs) have been increasingly accepted to function importantly in human diseases by serving as competing endogenous RNAs (ceRNAs). To date, the ceRNA mechanisms of lncRNAs in the progression of atherosclerosis (AS) remain largely unclear. On the basis of ceRNA theory, we implemented a multistep computational analysis to construct an lncRNA-mRNA network for AS progression (ASpLMN). The probe reannotation method and microRNA-target interactions from databases were systematically integrated. Three lncRNAs (GS1-358P8.4, OIP5-AS1, and TUG1) with central topological features in the ASpLMN were firstly identified. By using subnetwork analysis, we then obtained two highly clustered modules and one dysregulated module from the ASpLMN network. These modules, sharing three lncRNAs (GS1-358P8.4, OIP5-AS1, and RP11-690D19.3), were significantly enriched in biological pathways such as regulation of actin cytoskeleton, tryptophan metabolism, lysosome, and arginine and proline metabolism. In addition, random walking in the ASpLMN network indicated that lncRNA RP1-39G22.7 and MBNL1-AS1 may also play an essential role in the pathology of AS progression. The identified six lncRNAs from the aforementioned steps could distinguish advanced- from early-staged AS, with a strong diagnostic power for AS occurrence. In conclusion, the results of this study will improve our understanding about the ceRNA-mediated regulatory mechanisms in AS progression, and provide novel lncRNAs as biomarkers or therapeutic targets for acute cardiovascular events.

Dual impacts of lncRNA XIST and lncRNA SNHG5 on inflammatory reaction and apoptosis of endothelial cells via regulating miR‐155/CARHSP1 axis

Considering the significance of lncRNA/miRNA axis in explaining atherosclerosis (AS) progression, this investigation was intended to clarify whether lncRNAs XIST/SNHG5 would regulate AS aetiology by sponging miR‐155, an AS‐promoting molecule. We altogether recruited 367 patients who were examined by coronary angiography, and meanwhile, human coronary artery endothelial cells (HCAECs) were purchased to establish cells models via ox‐LDL treatment. The study results indicated that lowly expressed XIST/SNHG5 and highly expressed miR‐155 were frequently detectable among AS patients who showed severe stenosis and possessed high triglyceride (TG), low‐density lipoprotein cholesterol (LDL‐C) and high‐sensitivity C‐reactive protein (hs‐CRP) levels. Besides, HCAECs treated by ox‐LDL released large amounts of inflammatory cytokines, and their apoptosis rate was also raised. Moreover, expressions of XIST and SNHG5 declined markedly within ox‐LDL‐treated HCAECs, whereas miR‐155 expression significantly ascended. Transfection of pcDNA‐XIST and pcDNA‐SNHG5 both reduced the expression of TNF‐α, IL‐6, IL‐8 and IL‐1β within HCAECs and also dampened the apoptotic tendency of HCAECs. Co‐treatment of pcDNA‐XIST and pcDNA‐SNHG5 produced a larger effect on HCAEC activity than pcDNA‐XIST or pcDNA‐SNHG5 alone. Furthermore, miR‐155, modified by XIST and SNHG5, was capable of reversing the impacts of XIST and SNHG5 on HCAEC activity. Eventually, CARHSP1 was activated by XIST and SNHG5, and its overexpression dwindled impacts of miR‐155 mimic on proliferation and inflammation response of HCAECs. In conclusion, targeting XIST and SNHG5 might be an ideal alternative in delaying AS progression, allowing for their repression of downstream miR‐155.

3-Mercaptopyruvate sulfurtransferase/hydrogen sulfide protects cerebral endothelial cells against oxygen-glucose deprivation/reoxygenation-induced injury via mitoprotection and inhibition of the RhoA/ROCK pathway

3-Mercaptopyruvate sulfurtransferase (3-MST) is the major source of hydrogen sulfide (H₂S) production in the brain and participates in many physiological and pathological processes. The present study was designed to investigate the role of 3-MST-derived H₂S (3-MST/H₂S) on oxygen-glucose deprivation/reoxygenation (OGD/R) injury in cerebrovascular endothelial cells (ECs). Using cerebrovascular specimens from patients with acute massive cerebral infarction (MCI), we found abnormal morphology of the endothelium and mitochondria, as well as decreases in H₂S and 3-MST levels. In an OGD/R model of ECs, 3-mercaptopyruvate (3-MP) and l-aspartic acid (l-Asp) were used to stimulate or inhibit the production of 3-MST/H₂S. The results showed that OGD/R induced significant decreases in H₂S and 3-MST levels in both ECs and mitochondria, as well as increases in oxidative stress and mitochondrial energy imbalance. Cellular oxidative stress, destruction of mitochondrial ultrastructure, accumulation of mitochondrial reactive oxygen species (ROS), reduction of mitochondrial adenosine triphosphate (ATP) synthase activity and ATP production, and decreased mitochondrial membrane potential were all significantly ameliorated by 3-MP, whereas they were exacerbated by l-Asp pretreatment. Contrary to the effects of l-Asp, the increase in RhoA activity and expression of ROCK₁ and ROCK₂ induced by OGD/R were markedly inhibited by 3-MP pretreatment in subcellular fractions without mitochondria and mitochondrial fractions. In addition, 3-MST^-/- rat ECs displayed greater oxidative stress than 3-MST^+/+ rat ECs after OGD/R injury. These findings suggest that 3-MST/H₂S protects ECs against OGD/R-induced injury, which may be related to preservation of mitochondrial function and inhibition of the RhoA/ROCK pathway.

Serine-threonine kinase ROCK2 regulates germinal center B cell positioning and cholesterol biosynthesis

Germinal center (GC) responses require B cells to respond to a dynamic set of intercellular and microenvironmental signals that instruct B cell positioning, differentiation, and metabolic reprogramming. RHO-associated coiled-coil-containing protein kinase 2 (ROCK2), a serine-threonine kinase that can be therapeutically targeted by ROCK inhibitors or statins, is a key downstream effector of RHOA GTPases. Although RHOA-mediated pathways are emerging as critical regulators of GC responses, the role of ROCK2 in B cells is unknown. Here, we found that ROCK2 was activated in response to key T cell signals like CD40 and IL-21 and that it regulated GC formation and maintenance. RNA-Seq analyses revealed that ROCK2 controlled a unique transcriptional program in GC B cells that promoted optimal GC polarization and cholesterol biosynthesis. ROCK2 regulated this program by restraining AKT activation and subsequently enhancing FOXO1 activity. ATAC-Seq (assay for transposase-accessible chromatin with high-throughput sequencing) and biochemical analyses revealed that the effects of ROCK2 on cholesterol biosynthesis were instead mediated via a novel mechanism. ROCK2 directly phosphorylated interferon regulatory factor 8 (IRF8), a crucial mediator of GC responses, and promoted its interaction with sterol regulatory element-binding transcription factor 2 (SREBP2) at key regulatory regions controlling the expression of cholesterol biosynthetic enzymes, resulting in optimal recruitment of SREBP2 at these sites. These findings thus uncover ROCK2 as a multifaceted and therapeutically targetable regulator of GC responses.

Determination of KD025 (SLx-2119), a Selective ROCK2 Inhibitor, in Rat Plasma by High-Performance Liquid Chromatography-Tandem Mass Spectrometry and its Pharmacokinetic Application

KD025 (SLx-2119), the first specific Rho-associated protein kinase 2 (ROCK2) inhibitor, is a potential new drug candidate currently undergoing several phase 2 clinical trials for psoriasis, idiopathic pulmonary fibrosis, chronic graft-versus-host disease, and systemic sclerosis. In this study, a bio-analytical method was developed and fully validated for the quantification of KD025 in rat plasma and for application in pharmacokinetic studies. KD025 and GSK429286A (the internal standard) in rat plasma samples were analyzed by high-performance liquid chromatography-tandem mass spectrometry with m/z transition values of 453.10 → 366.10 and 433.00 → 178.00, respectively. The method was fully validated according to the United State Food and Drug Administration guidelines in terms of selectivity, linearity, accuracy, precision, sensitivity, matrix effects, extraction recovery, and stability. The method enabled the quantification of KD025 levels in rat plasma following oral administration of 5 mg/kg KD025 and intravenous administration of 2 mg/kg KD025 to rats, respectively. Our findings suggest that the developed method is practical and reliable for pharmacokinetic studies of KD025 in preclinical animals.

Targeting ROCK signaling in health, malignant and non-malignant diseases

A Rho-associated coiled-coil kinase (ROCK) is identified as a critical downstream effector of GTPase RhoA which contains two isoforms, ROCK1 (also known as p160ROCK and ROKβ) and ROCK2 (also known as Rho-kinase and ROKα), the gene of which is placed on chromosomes 18 (18q11.1) and 2 (2p24), respectively. ROCKs have a principal function in the generation of actin-myosin contractility and regulation of actin cytoskeleton dynamics. They represent a chief role in regulating various cellular functions, such as apoptosis, growth, migration, and metabolism through modulation of cytoskeletal actin synthesis, and cellular contraction through phosphorylation of numerous downstream targets. Emerging evidence has indicated that ROCKs present a significant function in cardiac physiology. Of note, dysregulation of ROCKs involves in several cardiac pathological processes like cardiac hypertrophy, cardiac fibrosis, systemic blood pressure disorder, and pulmonary hypertension. Moreover, ROCKs, in addition to their role in regulating renal arteriolar contraction, glomerular blood flow, and filtration, can also play a role in controlling podocytes, tubular cells, and mesangial cell structure and function. Hyperactivity disorder and over-gene expression of Rho/ROCK have been indicated in different cancers. Furthermore, it seems that increasing the expression of mRNA or ROCK protein has an undesirable effect on patient survival and has a positive impact on the progression and worsening of disease prognosis. This review focuses on the physiological and pathological functions of ROCKs with a particular view on its possible value of ROCK inhibitors as a new therapy in cancers and non-cancer diseases.

Association of DIAPH1 gene polymorphisms with ischemic stroke

DIAPH1 is a formin protein involved in actin polymerization with important roles in vascular remodeling and thrombosis. To investigate potential associations of DIAPH1 single-nucleotide polymorphisms (SNPs) with hypertension and stroke, 2,012 patients with hypertension and 2,210 controls, 2,966 stroke cases [2,212 ischemic stroke (IS), 754 hemorrhagic stroke (HS)] and 2,590 controls were enrolled respectively in the case-control study. A total of 4,098 individual were included in the cohort study. DIAPH1 mRNA expression was compared between 66 IS [43 small artery occlusion (SAO) and 23 large-artery atherosclerosis (LAA)] and 58 controls. Odds ratio (OR), hazard ratio (HR) and 95% confidence interval (CI) were calculated by logistic and cox regression analysis. Rs7703688 T>C variation was significantly associated with an increased risk of IS [OR (95% CI) was 1.721 (1.486-1.993), P=4.139×10^-12]. Association of rs7703688 with stroke risk was further validated in the cohort study [adjusted HRs (95% CIs) for additive and recessive models were 1.385 (1.001-1.918), P=0.049, and 2.882 (1.038-8.004), P=0.042, respectively)]. DIAPH1 mRNA expression was significantly downregulated in IS. In SAO stroke subtype, DIAPH1 expression has an increased trend among rs251019 genotypes (P_trend=0.048). These novel findings suggest that DIAPH1 variation contributes to genetic susceptibility to stroke risk, especially the SAO subtype of IS.

Targeting Rho-associated coiled-coil forming protein kinase (ROCK) in cardiovascular fibrosis and stiffening

Introduction: Pathological cardiac fibrosis, through excessive extracellular matrix protein deposition from fibroblasts and pro-fibrotic immune responses and vascular stiffening is associated with most forms of cardiovascular disease. Pathological cardiac fibrosis and stiffening can lead to heart failure and arrythmias and vascular stiffening may lead to hypertension. ROCK, a serine/threonine kinase downstream of the Rho-family of GTPases, may regulate many pro-fibrotic and pro-stiffening signaling pathways in numerous cell types.Areas covered: This article outlines the molecular mechanisms by which ROCK in fibroblasts, T helper cells, endothelial cells, vascular smooth muscle cells, and macrophages mediate fibrosis and stiffening. We speculate on how ROCK could be targeted to inhibit cardiovascular fibrosis and stiffening.Expert opinion: Critical gaps in knowledge must be addressed if ROCK inhibitors are to be used in the clinic. Numerous studies indicate that each ROCK isoform may play differential roles in regulating fibrosis and may have opposing roles in specific tissues. Future work needs to highlight the isoform- and tissue-specific contributions of ROCK in fibrosis, and how isoform-specific ROCK inhibitors in murine models and in clinical trials affect the pathophysiology of cardiac fibrosis and stiffening. This could progress knowledge regarding new treatments for heart failure, arrythmias and hypertension and the repair processes after myocardial infarction.

Evidence Supporting the Hypothesis That Inflammation-Induced Vasospasm Is Involved in the Pathogenesis of Acquired Sensorineural Hearing Loss

Sensorineural hearing loss is mainly acquired and affects an estimated 1.3 billion humans worldwide. It is related to aging, noise, infection, ototoxic drugs, and genetic defects. It is essential to identify reversible and preventable causes to be able to reduce the burden of this disease. Inflammation is involved in most causes and leads to tissue injury through vasospasm-associated ischemia. Vasospasm is reversible. This review summarized evidence linking inflammation-induced vasospasm to several forms of acquired sensorineural hearing loss. The link between vasospasm and sensorineural hearing loss is directly evident in subarachnoid haemorrhage, which involves the release of vasoconstriction-inducing cytokines like interleukin-1, endothelin-1, and tumour necrosis factor. These proinflammatory cytokines can also be released in response to infection, autoimmune disease, and acute or chronically increased inflammation in the ageing organism as in presbyacusis or in noise-induced cochlear injury. Evidence of vasospasm and hearing loss has also been discovered in bacterial meningitis and brain injury. Resolution of inflammation-induced vasospasm has been associated with improvement of hearing in autoimmune diseases involving overproduction of interleukin-1 from inflammasomes. There is mainly indirect evidence for vasospasm-associated sensorineural hearing loss in most forms of systemic or injury- or infection-induced local vascular inflammation. This opens up avenues in prevention and treatment of vascular and systemic inflammation as well as vasospasm itself as a way to prevent and treat most forms of acquired sensorineural hearing loss. Future research needs to investigate interventions antagonising vasospasm and vasospasm-inducing proinflammatory cytokines and their production in randomised controlled trials of prevention and treatment of acquired sensorineural hearing loss. Prime candidates for interventions are hereby inflammasome inhibitors and vasospasm-reducing drugs like nitric oxide donors, rho-kinase inhibitors, and magnesium which have the potential to reduce sensorineural hearing loss in meningitis, exposure to noise, brain injury, arteriosclerosis, and advanced age-related and autoimmune disease-related inflammation.

MicroRNA-92a promotes vascular smooth muscle cell proliferation and migration through the ROCK/MLCK signalling pathway

To identify the interaction between known regulators of atherosclerosis, microRNA-92a (miR-92a), Rho-associated coiled-coil-forming kinase (ROCK) and myosin light chain kinase (MLCK), we examined their expressions during proliferation and migration of platelet-derived growth factor-BB (PDGF-BB)-regulated vascular smooth muscle cells (VSMCs), both in vivo and in vitro. During the formation of atherosclerosis plaque in mice, a parallel increase in expression levels of MLCK and miR-92a was observed while miR-92a expression was reduced in ML-7 (an inhibitor of MLCK) treated mice and in MLCK-deficient VSMCs. In vitro results indicated that both MLCK and miR-92a shared the same signalling pathway. Transfection of miR-92a mimic partially restored the effect of MLCK's deficiency and antagonized the effect of Y27632 (an inhibitor of ROCK) on the down-regulation of VSMCs activities. ML-7 increased the expression of Kruppel-like factor 4 (KLF4, a target of miR-92a), and siRNA-KLF4 increased VSMCs' activity level. Consistently, inhibition of either MLCK or ROCK enhanced the KLF4 expression. Moreover, we observed that ROCK/MLCK up-regulated miR-92a expression in VSMCs through signal transducer and activator of transcription 3 (STAT3) activation. In conclusion, the activation of ROCK/STAT3 and/or MLCK/STAT3 may up-regulate miR-92a expression, which subsequently inhibits KLF4 expression and promotes PDGF-BB-mediated proliferation and migration of VSMCs. This new downstream node in the ROCK/MLCK signalling pathway may offer a potential intervention target for treatment of atherosclerosis.

Druggable targets in the Rho pathway and their promise for therapeutic control of blood pressure

The prevalence of high blood pressure (also known as hypertension) has steadily increased over the last few decades. Known as a silent killer, hypertension increases the risk for cardiovascular disease and can lead to stroke, heart attack, kidney failure and associated sequela. While numerous hypertensive therapies are currently available, it is estimated that only half of medicated patients exhibit blood pressure control. This signifies the need for a better understanding of the underlying cause of disease and for more effective therapies. While blood pressure homeostasis is very complex and involves the integrated control of multiple body systems, smooth muscle contractility and arterial resistance are important contributors. Strong evidence from pre-clinical animal models and genome-wide association studies indicate that smooth muscle contraction and BP homeostasis are governed by the small GTPase RhoA and its downstream target, Rho kinase. In this review, we summarize the signaling pathways and regulators that impart tight spatial-temporal control of RhoA activity in smooth muscle cells and discuss current therapeutic strategies to target these RhoA pathway components. We also discuss known allelic variations in the RhoA pathway and consider how these polymorphisms may affect genetic risk for hypertension and its clinical manifestations.

Rho Kinase Inhibitors as a Novel Treatment for Glaucoma and Ocular Hypertension

In an elegant example of bench-to-bedside research, a hypothesis that cells in the outflow pathway actively regulate conventional outflow resistance was proposed in the 1990s and systematically pursued, exposing novel cellular and molecular mechanisms of intraocular pressure (IOP) regulation. The critical discovery that pharmacologic manipulation of the cytoskeleton of outflow pathway cells decreased outflow resistance placed a spotlight on the Rho kinase pathway that was known to regulate the cytoskeleton. Ultimately, a search for Rho kinase inhibitors led to the discovery of several molecules of therapeutic interest, leaving us today with 2 new ocular hypotensive agents approved for clinical use: ripasudil in Japan and netarsudil in the United States. These represent members of the first new class of clinically useful ocular hypotensive agents since the US Food and Drug Administration approval of latanoprost in 1996. The development of Rho kinase inhibitors as a class of medications to lower IOP in patients with glaucoma and ocular hypertension represents a triumph in translational research. Rho kinase inhibitors are effective alone or when combined with other known ocular hypotensive medications. They also offer the possibility of neuroprotective activity, a favorable impact on ocular blood flow, and even an antifibrotic effect that may prove useful in conventional glaucoma surgery. Local adverse effects, however, including conjunctival hyperemia, subconjunctival hemorrhages, and cornea verticillata, are common. Development of Rho kinase inhibitors targeted to the cells of the outflow pathway and the retina may allow these agents to have even greater clinical impact. The objectives of this review are to describe the basic science underlying the development of Rho kinase inhibitors as a therapy to lower IOP and to summarize the results of the clinical studies reported to date. The neuroprotective and vasoactive properties of Rho kinase inhibitors, as well as the antifibrotic properties, of these agents are reviewed in the context of their possible role in the medical and surgical treatment of glaucoma.

Rho-kinase/AMPK axis regulates hepatic lipogenesis during overnutrition

Obesity is a major risk factor for developing nonalcoholic fatty liver disease (NAFLD). NAFLD is the most common form of chronic liver disease and is closely associated with insulin resistance, ultimately leading to cirrhosis and hepatocellular carcinoma. However, knowledge of the intracellular regulators of obesity-linked fatty liver disease remains incomplete. Here we showed that hepatic Rho-kinase 1 (ROCK1) drives obesity-induced steatosis in mice through stimulation of de novo lipogenesis. Mice lacking ROCK1 in the liver were resistant to diet-induced obesity owing to increased energy expenditure and thermogenic gene expression. Constitutive expression of hepatic ROCK1 was sufficient to promote adiposity, insulin resistance, and hepatic lipid accumulation in mice fed a high-fat diet. Correspondingly, liver-specific ROCK1 deletion prevented the development of severe hepatic steatosis and reduced hyperglycemia in obese diabetic (ob/ob) mice. Of pathophysiological significance, hepatic ROCK1 was markedly upregulated in humans with fatty liver disease and correlated with risk factors clustering around NAFLD and insulin resistance. Mechanistically, we found that hepatic ROCK1 suppresses AMPK activity and a ROCK1/AMPK pathway is necessary to mediate cannabinoid-induced lipogenesis in the liver. Furthermore, treatment with metformin, the most widely used antidiabetes drug, reduced hepatic lipid accumulation by inactivating ROCK1, resulting in activation of AMPK downstream signaling. Taken together, our findings establish a ROCK1/AMPK signaling axis that regulates de novo lipogenesis, providing a unique target for treating obesity-related metabolic disorders such as NAFLD.

Total flavones of Rhododendron simsii Planch flower protect isolated rat heart from ischaemia-reperfusion injury and its mechanism of UTR-RhoA-ROCK pathway inhibition

Objectives

Total flavones of Rhododendron simsii Planch flower (TFR) are an effective part extracted from the flower. The present study was designed to investigate the protective effect of TFR in isolated rat heart following global ischaemia-reperfusion and the possible underlying mechanisms.

Methods

Langendorff perfusion apparatus was used to perfuse isolated rat heart which was subjected to global ischaemia-reperfusion. The hemodynamic parameters were continuously monitored. Coronary flow as well as lactate dehydrogenase (LDH), creatine phosphokinase-MB (CK-MB) and cardiac troponin I (cTnI) in coronary effluents was measured. RhoA activity and urotensin receptor (UTR) and Rho-related coiled-coil-forming protein kinase (ROCK) protein expressions in rat myocardium were examined, respectively. Cardiac dysfunction was indicated by the alterations of hemodynamic parameters and the reduced coronary flow.

Key findings

Total flavones of Rhododendron simsii Planch flower significantly improved ischaemia-reperfusion–induced cardiac dysfunction and leakages of LDH, CK-MB and cTnI, and inhibited myocardial ischaemia-reperfusion–increased RhoA activity and UTR, ROCK1 and ROCK2 protein expressions. The improvement of TFR in the cardiac dysfunction and the leakage of LDH, CK-MB and cTnI were markedly attenuated under the UTR blockade and ROCK inhibition. TFR-inhibited RhoA activity was decreased under the UTR blockade.

Conclusions

Total flavones of Rhododendron simsii Planch flower had a protective effect on ischaemia-reperfusion injury in isolated rat heart, which may be attributed to the blocking of UTR and subsequent inhibition of the RhoA-ROCK pathway.

Protective effects of Schisandrin on high glucose-induced changes of RhoA and eNOS activity in human umbilical vein endothelial cells

Schisandrin, derived from the Chinese medicinal herb Schisandra chinensis, has been found to confer protective effects on circulation systems. But the underlying molecular mechanisms remain unclear. The aim of this study was to investigate the effects of a high level of glucose on RhoA and eNOS activity in human umbilical vein endothelial cells(HUVECs) and how Schisandrin plays a role in mediating these effects. To find the optimal treatment time, HUVECs were cultured at a high glucose concentration (30 mM) for different lengths of time (0, 12, 24, and 48 h). Subsequently, the cells were randomized into five groups: a normal group, a high glucose group, and three high glucose groups that were given different doses (5, 10, and 20 μM) of Schisandrin. The cells were pretreated with Schisandrin for 24 h before stimulation with high glucose. The morphology of HUVECs in the various groups was assessed under a light microscope. Immunocytochemical staining was used to detect the level of p-MYPT1 expression. The levels of RhoA activity were determined using the RhoA Activation Assay Biochem Kit. The levels of eNOS activity were examined using a nitrate reduction test. The results showed that in the high glucose group, the activity of RhoA was increased and the activity of eNOS was reduced, thus decreasing the secretion of NO. However, after pretreatment with Schisandrin (10, 20 μM), the activity of RhoA was inhibited and the activity of eNOS increased, which led to an increase in NO production compared with the high glucose group. There was no evident difference between the 5 μM Schisandrin group and the high glucose group. Taken together, these findings indicate that Schisandrin can improve the function of endothelial cells by lowering the activity of RhoA/Rho kinase and raising both the activity of eNOS and the production of NO.

Identification of key genes and miRNAs associated with carotid atherosclerosis based on mRNA-seq data

This study was aimed to explore the crucial genes and microRNAs (miRNAs) associated with the carotid atherosclerosis (CA).Two public datasets GSE28829 and GSE43292 were obtained from Gene Expression Omnibus databases to analyze the differentially expressed genes (DEGs) between primary and advanced atherosclerotic plaque tissues. The Gene Ontology (GO) terms, pathways, and protein-protein interactions (PPIs) of these DEGs were analyzed. miRNAs and transcription factor (TF) were predicted.A total of 112 upregulated and 179 downregulated intersection DEGs were identified between 2 datasets. In the PPI network, HSP90AB1 (degree = 19), RAP1A (degree = 14), and integrin subunit beta 1 (ITGB1) had higher degrees. A total of 23 miRNAs were predicted, such as miR-126, miR-155, miR-19A, and miR-19B. Four TFs were associated with upregulated DEGs, while 10 TFs were identified to be associated with downregulated genes.Our study suggests the important roles of HSP90AB1, RAP1A, and integrins proteins of ITGB1, ITGA11, ITGA9, and ITGB2 in the progression of CA plaque. Additionally, miR-126, miR-155, miR-19B, and miR-19A may be considered as biomarkers of CA.

In Development-A New Paradigm for Understanding Vascular Disease

Under physiological conditions, the arterial endothelium exerts a powerful protective influence to maintain vascular homeostasis. However, during the development of vascular disease, these protective activities are lost, and dysfunctional endothelial cells actually promote disease pathogenesis. Numerous investigations have analyzed the characteristics of dysfunctional endothelium with a view to understanding the processes responsible for the dysfunction and to determining their role in vascular pathology. This review adopts an alternate approach: reviewing the mechanisms that contribute to the initial formation of a healthy protective endothelium and on how those mechanisms may be disrupted, precipitating the appearance of dysfunctional endothelial cells and the progression of vascular disease. This approach, which highlights the role of endothelial adherens junctions and vascular endothelial-cadherin in endothelial maturation and endothelial dysfunction, provides new insight into the remarkable biology of this important cell layer and its role in vascular protection and vascular disease.

The Rho-associated kinase inhibitors Y27632 and fasudil promote microglial migration in the spinal cord via the ERK signaling pathway

Rho-associated kinase (ROCK) is a key regulatory protein involved in inflammatory secretion in microglia in the central nervous system. Our previous studies showed that ROCK inhibition enhances phagocytic activity in microglia through the extracellular signal-regulated kinase (ERK) signaling pathway, but its effect on microglial migration was unknown. Therefore, in this study, we investigated the effects of the ROCK inhibitors Y27632 and fasudil on the migratory activity of primary cultured microglia isolated from the spinal cord, and we examined the underlying mechanisms. The microglia were treated with Y27632, fasudil and/or the ERK inhibitor U0126. Cellular morphology was observed by immunofluorescence. Transwell chambers were used to assess cell migration. ERK levels were measured by in-cell western blot assay. Y27632 and fasudil increased microglial migration, and the microglia were irregularly shaped and had many small processes. These inhibitors also upregulated the levels of phosphorylated ERK protein. The ERK inhibitor U0126 suppressed these effects of Y27632 and fasudil. These findings suggest that the ROCK inhibitors Y27632 and fasudil promote microglial migration in the spinal cord through the ERK signaling pathway.

Common variants of ROCKs and the risk of hypertension, and stroke: Two case-control studies and a follow-up study in Chinese Han population

The Rho kinases (ROCKs) are recognized as a critical regulator of vascular functions in cardiovascular disorders. It is crucial to illustrate the association of ROCKs genetic variation and hypertension and/or stroke events. Herein we aimed at investigating the association of ROCK1 and ROCK2 with hypertension and stroke in Chinese Han population. Seven tagSNPs at ROCK1 and ROCK2 were genotyped in a community-based case-control study consisting of 2012 hypertension cases and 2210 normotensive controls and 4128 subjects were further followed up. In stroke case-control study, 1471 ischemic stroke (IS) inpatients and 607 hemorrhagic stroke (HS) inpatients were collected, and 2443 age-matched controls were selected from the follow-up population. Risks were estimated as odds ratio (OR) and hazard ratio (HR) by logistic and Cox regression. The community-based case-control study didn't identify any significant tagSNPs associated with hypertension even after adjustment for covariates. The follow-up analysis showed that rs1481280 of ROCK1 significantly associated with incident hypertension (HR=1.130, P=0.048) after adjusting for covariates. rs7589629 and rs978906 of ROCK2 were significantly associated with incident IS (HR=1.373, P=0.004; HR=1.284, P=0.026) respectively. In stroke case-control study, rs288980, rs1481280 and rs7237677 were significantly associated with IS and the adjusted ORs (P values) of additive model were 0.879 (0.010), 0.895 (0.036) and 0.857 (0.002) respectively. Furthermore, rs288980, rs7237677 and rs978906 were significantly associated with HS and the adjusted ORs (P values) of additive model were 0.857 (0.025), 0.848 (0.018) and 0.856 (0.027) respectively. Our findings suggest that ROCK1 and ROCK2 contribute to the genetic susceptibility of hypertension and stroke.

Leukocyte RhoA exchange factor Arhgef1 mediates vascular inflammation and atherosclerosis

Abnormal activity of the renin-angiotensin-aldosterone system plays a causal role in the development of hypertension, atherosclerosis, and associated cardiovascular events such as myocardial infarction, stroke, and heart failure. As both a vasoconstrictor and a proinflammatory mediator, angiotensin II (Ang II) is considered a potential link between hypertension and atherosclerosis. However, a role for Ang II-induced inflammation in atherosclerosis has not been clearly established, and the molecular mechanisms and intracellular signaling pathways involved are not known. Here, we demonstrated that the RhoA GEF Arhgef1 is essential for Ang II-induced inflammation. Specifically, we showed that deletion of Arhgef1 in a murine model prevents Ang II-induced integrin activation in leukocytes, thereby preventing Ang II-induced recruitment of leukocytes to the endothelium. Mice lacking both LDL receptor (LDLR) and Arhgef1 were protected from high-fat diet-induced atherosclerosis. Moreover, reconstitution of Ldlr-/- mice with Arhgef1-deficient BM prevented high-fat diet-induced atherosclerosis, while reconstitution of Ldlr-/- Arhgef1-/- with WT BM exacerbated atherosclerotic lesion formation, supporting Arhgef1 activation in leukocytes as causal in the development of atherosclerosis. Thus, our data highlight the importance of Arhgef1 in cardiovascular disease and suggest targeting Arhgef1 as a potential therapeutic strategy against atherosclerosis.