Search Results (369)

Glaucoma is recognized as a progressive optic neuropathy and a leading cause of irreversible blindness worldwide. While intraocular pressure (IOP) is considered the only modifiable risk factor, current medical treatments are challenged by issues such as inadequate IOP control and ocular side effects. Rho kinase (ROCK) inhibitors have been developed as a novel pharmacologic class targeting the trabecular meshwork to enhance conventional aqueous humor outflow. In this review, the pharmacokinetics and IOP-lowering efficacy of key ROCK inhibitors are summarized. Beyond IOP reduction, ROCK inhibitors exhibit neuroprotective, anti-inflammatory, antifibrotic, and ocular perfusion-enhancing effects. Finally, we analyzed the limitations and future prospects of ROCK inhibitors in the management of glaucoma. Full article

Objective: To investigate the neuroprotective effects of a Rho-associated kinase (ROCK) inhibitor on retinal ganglion cells (RGCs) in vitro and in vivo. Methods: For in vivo studies, a unilateral optic nerve crush mouse model was established. Then, 100 mM Y-27632 (a ROCK inhibitor) or saline was applied to the experimental eyes once a day for 14 days. The effects of the ROCK inhibitor were evaluated by counting the surviving RGCs in the enucleated flat retina tissues and measuring the inner retinal thickness using optical coherence tomography (OCT), the amplitude of the electroretinogram (ERG), and the change in intraocular pressure (IOP). For the in vitro study, RGCs were isolated from five-day-old mice using a modified immunopanning method with magnetic beads. The isolated RGCs were incubated for 72 h with various concentrations of Y-27632, after which TUNEL assays were performed to determine the number of surviving RGCs. Results: Y-27632 has neuroprotective effects, as it significantly increased the number of surviving RGCs by approximately 6.3%. OCT and ERG data also revealed that Y-27632 induced neuroprotective effects in vivo; furthermore, Y-27632 reduced IOP by approximately 18.3%. The in vitro study revealed the dose-dependent neuroprotective effects of Y-27632, with the highest dose of Y-27632 (1000 nM) increasing the RGC survival rate after 72 h of incubation compared with that of the control. Conclusions: The ROCK inhibitor Y-27632 may exert some neuroprotective effects on RGCs when it is used as an eye drop through an IOP-independent mechanism. Full article

This study aims to investigate the mechanism by which the total flavones of Rhododendron (TFR) protect against cerebral ischemic injury through the endothelial-derived H₂S-mediated regulation of RhoA phosphorylation at the Ser188 and Rho kinase 2 (ROCK₂) phosphorylation at Thr436. For experimental design, mouse or rat cerebrovascular endothelial cells (ECs) were cultured with or without neurons and subjected to hypoxia/reoxygenation (H/R) injury. The vasodilation of the cerebral basilar artery was assessed. Cerebral ischemia/reperfusion (I/R) injury was induced in mice by bilateral carotid artery ligation, followed by Morris water maze and open field behavioral assessments. The protein levels of cystathionine-γ-lyase (CSE), 3-mercaptopyruvate sulfurtransferase (3-MST), RhoA, ROCK₂, p-RhoA (RhoA phosphorylated at Ser188), and p-ROCK₂ (ROCK₂ phosphorylated at Thr436) were quantified. Additionally, the activities of RhoA and ROCK₂ were measured. Notably, TFR significantly inhibited H/R-induced H₂S reduction and suppressed the increased expression and activity of RhoA and ROCK₂ in ECs, effects attenuated by CSE or 3-MST knockout. Moreover, TFR-mediated cerebrovascular dilation was reduced by RhoA or ROCK₂ inhibitors, while the protective effect of TFR against cerebral I/R injury in mice was markedly attenuated by the heterozygous knockout of ROCK₂. In the ECs-co-cultured neurons, the inhibition of TFR on H/R-induced neuronal injury and decrease in H₂S level in the co-culture was attenuated by the knockout of CSE or 3-MST in the ECs. TFR notably inhibited the H/R-induced upregulation of neuronal RhoA, ROCK₂, and p-ROCK₂ protein levels, as well as the activities of RhoA and ROCK₂, while reversing the decrease in p-RhoA. However, the knockout of CSE or 3-MST in the ECs significantly attenuated the inhibition of TFR on these increases. Furthermore, 3-MST knockout in ECs attenuated the TFR-mediated suppression of p-RhoA reduction. Additionally, CSE or 3-MST knockout in ECs exacerbated H/R-induced neuronal injury, reduced H₂S level in the co-culture system, and increased RhoA activity and ROCK₂ expression in neurons. In summary, TFR protected against ischemic cerebral injury by endothelial-derived H₂S promoting the phosphorylation of RhoA at Ser188 but inhibited the phosphorylation of ROCK₂ at Thr436 to inhibit the RhoA-ROCK₂ pathway in neurons. Full article

Background/Objectives: Rho-associated coiled-coil-containing protein kinase inhibitors (ROCKis) have now become known as modulators of corneal endothelial wound repair and cell survival. However, evidence remains fragmented across laboratory and clinical reports. We performed a systematic review to synthesize preclinical and clinical data on ROCKis in corneal disease, assess their efficacy and safety, and identify research gaps. Methods: We searched PubMed, Web of Science, Scopus, and Google Scholar (until May 2025) for English-language original studies evaluating ROCKis in corneal models or patients. Inclusion criteria encompassed in vitro, ex vivo, in vivo, and clinical trials reporting functional outcomes (endothelial cell density, wound closure, visual acuity). Results: Thirty-one studies met criteria: 14 preclinical studies and 17 clinical studies. Preclinical models (rabbit, porcine, human explants) uniformly showed ROCKis (Y-27632, Ripasudil, Netarsudil, H-1152) accelerate corneal endothelial cell proliferation, migration, and restoration of a hexagonal monolayer with improved barrier and pump function over days to weeks. In 17 clinical investigations, topical Ripasudil or Netarsudil and cultured cell injections achieved significant corneal thinning, endothelial cell density and central corneal thickness changes, and visual acuity improvements (≥2 lines) with minimal adverse events. Overall bias was moderate in non-randomized studies and low in the RCTs. Conclusions: ROCKis demonstrate consistent pro-regenerative effects on corneal endothelium in multiple models and show promising clinical efficacy in Fuchs endothelial dystrophy and pseudophakic endothelial failure. Future work should explore novel delivery systems and larger controlled trials to optimize dosing, safety, and long-term outcomes. Full article

Calcium (Ca²⁺) signaling is a fundamental regulatory mechanism controlling essential processes in the endothelium, vascular smooth muscle cells (VSMCs), and the extracellular matrix (ECM), including maintaining the endothelial barrier, modulation of vascular tone, and vascular remodeling. Cytosolic free Ca²⁺ concentration is tightly regulated by a balance between Ca²⁺ mobilization mechanisms, including Ca²⁺ release from the intracellular stores in the sarcoplasmic/endoplasmic reticulum and Ca²⁺ entry via voltage-dependent, transient-receptor potential, and store-operated Ca²⁺ channels, and Ca²⁺ elimination pathways including Ca²⁺ extrusion by the plasma membrane Ca²⁺-ATPase and Na⁺/Ca²⁺ exchanger and Ca²⁺ re-uptake by the sarco(endo)plasmic reticulum Ca²⁺-ATPase and the mitochondria. Some cell membranes/organelles are multifunctional and have both Ca²⁺ mobilization and Ca²⁺ removal pathways. Also, the individual Ca²⁺ handling pathways could be integrated to function in a regenerative, capacitative, cooperative, bidirectional, or reciprocal feed-forward or feed-back manner. Disruption of these pathways causes dysregulation of the Ca²⁺ signaling dynamics and leads to pathological cardiovascular conditions such as hypertension, coronary artery disease, atherosclerosis, and vascular calcification. In the endothelium, dysregulated Ca²⁺ signaling impairs nitric oxide production, reduces vasodilatory capacity, and increases vascular permeability. In VSMCs, Ca²⁺-dependent phosphorylation of the myosin light chain and Ca²⁺ sensitization by protein kinase-C (PKC) and Rho-kinase (ROCK) increase vascular tone and could lead to increased blood pressure and hypertension. Ca²⁺ activation of matrix metalloproteinases causes collagen/elastin imbalance and promotes vascular remodeling. Ca²⁺-dependent immune cell activation, leukocyte infiltration, and cholesterol accumulation by macrophages promote foam cell formation and atherosclerotic plaque progression. Chronic increases in VSMCs Ca²⁺ promote phenotypic switching to mesenchymal cells and osteogenic transformation and thereby accelerate vascular calcification and plaque instability. Emerging therapeutic strategies targeting these Ca²⁺-dependent mechanisms, including Ca²⁺ channel blockers and PKC and ROCK inhibitors, hold promise for restoring Ca²⁺ homeostasis and mitigating vascular disease progression. Full article

Background/Objectives: Sepsis remains one of the most serious and possibly fatal complications encountered in intensive care units. Considering the frequent use of narcotic analgesics in this setting, we investigated whether the cardiovascular and peripheral and central inflammatory features of sepsis could be modified by morphine. Methods: Rats were instrumented with femoral and intracisternal (i.c.) indwelling catheters and sepsis was induced by cecal ligation and puncture (CLP). Results: The i.v. administration of morphine (3 and 10 mg/kg) significantly and dose-dependently aggravated septic manifestations of hypotension and impaired cardiac autonomic activity, as reflected by the reductions in indices of heart rate variability (HRV). Cardiac contractility (dP/dtmax) was also reduced by morphine in septic rats. The morphine effects were mostly eliminated following (i) blockade of μ-opioid receptors by i.v. naloxone and (ii) inhibition of central PI3K, MAPK-ERK, MAPK-JNK, NADPH oxidase (NADPHox), or Rho-kinase (ROCK) by i.c. wortmannin, PD98059, SP600125, diphenyleneiodonium, and fasudil, respectively. Further, these pharmacologic interventions significantly reduced the heightened protein expression of toll-like receptor 4 (TLR4) and monocyte chemoattractant protein-1 (MCP1) in brainstem rostral ventrolateral medullary (RVLM), but not cardiac, tissues of CLP/morphine-treated rats. Conclusions: Morphine worsens cardiovascular and autonomic disturbances caused by sepsis through a mechanism mediated via μ-opioid receptors and upregulated central inflammatory, chemotactic, and oxidative signals. Clinical studies are warranted to re-affirm the adverse cardiovascular interaction between opioids and the septic challenge. Full article

Although chloroquine appears to inhibit the alpha-1 adrenoceptor, whether the chloroquine-mediated inhibition of phenylephrine-induced contraction is associated with the blockade of alpha-1 adrenoceptors remains unknown. This study examined the effect of chloroquine on contractions elicited by the alpha-1 adrenoceptor agonist phenylephrine in isolated rat aortas and determined the underlying mechanism. The effects of chloroquine and the alpha-1 adrenoceptor inhibitor prazosin on phenylephrine-elicited contractions were examined. The effects of the irreversible alpha-adrenoceptor inhibitor phenoxybenzamine followed by washout with fresh Krebs solution, as well as combined treatment with chloroquine and phenoxybenzamine followed by washout with fresh Krebs solution, on phenylephrine-induced contraction were investigated. Chloroquine and prazosin inhibited phenylephrine-induced contractions. However, pretreatment with prazosin eliminated the chloroquine-induced inhibition of contractions elicited by phenylephrine. Additionally, pretreatment with chloroquine and phenoxybenzamine followed by washout produced a higher contraction elicited by phenylephrine than pretreatment with phenoxybenzamine alone followed by washout. Although chloroquine did not affect the contraction induced by KCl in the endothelium-denuded aorta, it inhibited phenylephrine-induced protein kinase C (PKC) and myosin light-chain (MLC₂₀) phosphorylation and Rho-kinase membrane translocation. These results suggest that chloroquine inhibits vasoconstriction elicited by phenylephrine via alpha-1 adrenoceptor inhibition, which is mediated by decreased MLC₂₀ phosphorylation, the attenuation of PKC phosphorylation, and Rho-kinase membrane translocation. Full article

Sepsis-associated acute kidney injury (S-AKI) is a severe complication in critically ill patients, marked by inflammation, oxidative stress, and renal dysfunction. This study aimed to evaluate the renoprotective effects of Fasudil (Fas), a Rho-associated kinase inhibitor, in a rat model of S-AKI induced by cecal ligation and puncture (CLP). Thirty-six Wistar albino rats were divided into control, CLP with saline, and Fas (100 mg/kg/day intraperitoneally) groups. Biochemical, histopathological, and molecular analyses were conducted to assess kidney function, oxidative stress, and inflammation. Fas treatment significantly decreased plasma malondialdehyde and TNF-α levels, reducing oxidative stress and systemic inflammation. Kidney function markers, including BUN and creatinine, showed marked improvement. Furthermore, Fas suppressed the expression of STAT-3 and NLRP-3 in renal tissues, highlighting its role in modulating key inflammatory pathways. Histological evaluation revealed alleviated renal damage, with less tubular necrosis and interstitial inflammation in the Fas-treated group. In conclusion, Fas demonstrates significant anti-inflammatory, antioxidant, and nephroprotective effects in S-AKI, primarily by inhibiting STAT-3 and NLRP-3 signaling. These results support its potential as a therapeutic agent in sepsis-induced kidney injury and suggest the need for further clinical evaluation. Full article

Granulosa cell (GC) differentiation, stimulated by FSH and LH, drives oocyte maturation and follicle development. FSH promotes GC proliferation, and LH triggers ovulation. In clinical practice, hCG is used to mimic LH. Despite various controlled ovarian stimulation (COS) protocols employing exogenous gonadotropins and GnRH analogs to prevent premature ovulation, their effectiveness and safety remain debated. To identify markers predicting a positive treatment response, the secretome of gonadotropin-stimulated GC using the human granulosa-like tumor cell line (KGN) via proteomics was analyzed. Additionally, a novel 2D-FFT quantitative method was employed to assess cytoskeleton fiber aggregation and polymerization, which are critical processes for GC differentiation. Furthermore, the activation of key kinases, focal adhesion kinase (FAK), and Rho-associated coiled-coil-containing protein kinase 1 (ROCK-1), which are implicated in cytoskeleton dynamics and hormone signaling, was evaluated. The proteomic analysis revealed significant modulation of proteins involved in extracellular matrix organization, steroidogenesis, and cytoskeleton remodeling. Notably, the combined FSH/hCG treatment led to a dynamic upregulation of the semaphorin pathway, specifically semaphorin 7A. Finally, a significant reorganization of the cytoskeleton network and signaling was detected. These findings enhance our understanding of folliculogenesis and suggest potential novel molecular markers for predicting patient responses to gonadotropin stimulation. Full article

Fuchs endothelial corneal dystrophy (FECD) is the most common corneal endothelial dystrophy. It is characterized by the progressive loss of corneal endothelial cells (CECs), guttae formation on the Descemet membrane, and corneal edema, leading to visual impairment. Corneal transplantation remains the standard treatment, but it has limitations such as donor shortages, infection risk, and graft rejection. Rho-kinase (ROCK) inhibitors have emerged as a promising pharmacological alternative. These agents promote CEC proliferation, migration, and adhesion while inhibiting apoptosis and enhancing corneal endothelial wound healing. Several studies have demonstrated the efficacy of ROCK inhibitors in improving corneal clarity and endothelial function, particularly when used as an adjunct to Descemet Stripping Only (DSO) surgery. Additionally, they show potential in preventing corneal edema in FECD patients undergoing cataract surgery. The methodology involved a literature search through the PubMed and Medline databases using relevant keywords. Only peer-reviewed articles in English were included, with additional references from selected articles reviewed to ensure comprehensive coverage. ROCK inhibitors offer a novel pharmacological approach to managing FECD. They have shown potential in promoting endothelial cell regeneration and improving corneal functIion. Despite promising results, further research is required to determine ROCK inhibitors’ long-term safety, optimal dosing, and efficacy in surgical and non-surgical FECD patients. Their potential to delay or prevent corneal transplantation represents a significant advancement in FECD management. Full article

The p21-activated kinases (PAKs) are a group of evolutionarily conserved serine/threonine protein kinases and serve as a downstream target of the small GTPases Rac and Cdc42, both of which belong to the Rho family. PAKs play pivotal roles in various physiological processes, including cytoskeletal rearrangement and cellular signal transduction. Group II PAKs (PAK4-6) are particularly closely linked to human tumors, such as breast and pancreatic cancers, while Group I PAKs (PAK1-3) are indispensable for normal physiological functions such as cardiovascular development and neurogenesis. In recent years, the association of PAKs with diseases like cancer and the rise of small-molecule inhibitors targeting PAKs have attracted significant attention. This article focuses on the analysis of PAKs’ role in tumor progression and immune infiltration, as well as the current small-molecule inhibitors of PAKs and their mechanisms. Full article

Background/Objectives: Primary open-angle glaucoma (POAG) is an anterior optic neuropathy that can lead to irreversible vision loss if untreated. Prostaglandin analogues are the first-line treatment, but new drug classes, such as rho kinase (ROCK) inhibitors, are being explored. This review evaluates the efficacy and safety of ROCK inhibitors in treating POAG based on completed trials, comparing results with available natural history data and identifying areas for further research. Methods: A systematic database search was conducted in Ovid MEDLINE and Ovid Embase on 5 April 2022 using the following keywords: ‘glaucoma’, ‘rho kinase inhibitor’, ‘rho-kinase inhibitor’, ‘rock inhibitor’, ‘ripasudil’, ‘netarsudil’, and ‘fasudil’. Abstracts were screened for relevant studies and results summarized in tables. Results: The analysis of trials conducted for ROCK inhibitors reveals that they are a safe and efficacious drug to treat POAG, demonstrating non-inferiority to existing medical treatments. Comparison of data to natural history studies was inconclusive due to the lack of natural history studies and their limitations. The results showed ROCK inhibitors to be effective when combined with existing medical treatments. However, questions remain regarding the optimal dosage, patient selection, and cost-effectiveness. Outcome measures for future trials should be expanded to include additional methods of monitoring disease progression as well as patient quality-of-life. Conclusions: ROCK inhibitors have emerged with a favorable safety profile, efficaciously attenuating intraocular pressure. To elucidate their long-term therapeutic value and safety comprehensively, further independent, large-scale, prospective randomized controlled trials are warranted. Such studies are pivotal to augment our understanding of this emergent medication class. Full article

Aberrant Rho-associated kinase function could be associated with increased bone fragility. Since cigarette smoke (CS) exposure promotes the increase in bone fragility due to changes in bone tissue components, this study aimed to investigate how CS exposure could modulate the Rho kinase-associated bone structural changes. Mice were assigned to four groups: control; smoke; control with Rho kinase inhibitor administration; and smoke with a Rho kinase inhibitor. Bone samples were obtained to assess bone histomorphometry analysis, type I collagen composition, and MEPE expression in trabeculae. We observed that CS exposure induced decreased trabecular and osteoid thickness. A concomitant increase in the osteoclastic and erosion surfaces and a decrease in the mineralization surface were observed. Additionally, CS exposure decreased the type I collagen and MEPE expression. Rho kinase inhibitor administration recovered the bone mineralization and the collagen type I deposition. Conclusions: CS exposure increases Rho kinase activity in bone cells, leading to structural changes. The administration of a Rho GTPases inhibitor partially reverses these effects, likely due to the recovery in osteoblast activity. Full article

The Minute Virus of Canines (MVC), belonging to the genus Bocaparvovirus within the family Parvoviridae, is associated with enteritis and embryonic infection in neonatal canines. Viral attachment to host cells is a critical step in infection, and viral protein 2 (VP2) as an important structural protein of MVC influences host selection and infection severity. Nevertheless, little is known about the interaction between VP2 protein and host cells. In this study, we identified that VP2 directly interacts with the kinase domain of RhoA-associated protein kinase 1 (ROCK1) by using mass spectrometry and immunoprecipitation approach and demonstrated that the RhoA/ROCK1/myosin light chain 2 (MLC2) signaling pathway was activated during the early stage of MVC infection in Walter Reed canine cell/3873D (WRD) cells. Further studies indicated that RhoA/ROCK1-mediated phosphorylation of MLC2 triggers the contraction of the actomyosin ring, disrupts tight junctions, and exposes the tight junction protein Occludin, which facilitates the interaction between VP2 and Occludin. Specific inhibitors of RhoA and ROCK1 restored the MVC-induced intracellular translocation of Occludin and the increase in cell membrane permeability. Moreover, the two inhibitors significantly reduced viral protein expression and genomic copy number. Collectively, our study provides the first evidence that there is a direct interaction between the structural protein VP2 of MVC and ROCK1, and that the tight junction protein Occludin can serve as a potential co-receptor for MVC infection, which may offer new targets for anti-MVC strategies. Full article

Metastatic prostate cancer occurs when the tumor spreads from the prostate gland to other parts of the body. Previous studies have shown that Gα_i2, a subunit of the heterotrimeric G protein complex, plays a critical role in inducing cell migration and invasion in prostate cancer cells in response to diverse stimuli. Rac1 is a small rho-GTPase, which is activated by the phosphoinositide 3-kinase (PI3K)/AKT pathway and plays an essential role during cell migration. Previous studies have shown that the knockdown of Gα_i2 attenuates cell migration without causing any reduction in basal Rac1 activity in both PC3 and DU145 cells, and has only marginal effects on the epidermal growth facotor (EGF)-induced increase in Rac1 activity. Therefore, Gα_i2 may be involved in the regulation of cell motility and invasion independently or downstream of Rac1 activation. In this study, we investigated the possible mechanism of Gα_i2 at the level of the Rac1-dependent activation of Wiskott-Aldrich Syndrome Protein)-family verprolin homologous protein2 (Wave2) and actin related protein 2/3 (Arp 2/3) proteins, downstream effectors of activated Rac1. PC3 cells with a stable overexpression of constitutively active Rac1 were transfected with control siRNA or Gα_i2 siRNA to knockdown endogenous Gα_i2 expression. Western blot analysis showed that the Rac1-dependent activation of Wave2 was impaired in the absence of Gα_i2. The overexpression of constitutively active Gα_i2 (Gα_i2-Q205L) in PC3 cells significantly increased cell migration compared to cells transfected with control plasmids. In the parallel experiments, a specific Gα_i2 inhibitor blocked G_iα2-Q205L-induced cell migration in PC3 cells. Furthermore, the Rac1 inhibitor did not block increased cell migration in PC3 cells overexpressing constitutively active Gα_i2. We conclude that activated Gα_i2 plays a crucial role in cell migration in prostate cancer cells independent of Rac1 activation. Full article