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Currently, corneal blindness is affecting >10 million individuals worldwide, and there is a significant unmet medical need because only 1.5% of transplantation needs are met globally due to a lack of high-quality grafts. In light of this global health disaster, researchers are developing corneal substitutes that can resemble the human cornea in vivo and replace human donor tissue. Thus, this review examines ROCK (Rho-associated coiled-coil containing protein kinases) inhibitors as a potential corneal wound-healing (CWH) therapy by reviewing the existing clinical and nonclinical findings. The systematic review was done from PubMed, Scopus, Web of Science, and Google Scholar for CWH, corneal injury, corneal endothelial wound healing, ROCK inhibitors, Fasudil, Netarsudil, Ripasudil, Y-27632, clinical trial, clinical study, case series, case reports, preclinical study, in vivo, and in vitro studies. After removing duplicates, all downloaded articles were examined. The literature search included the data till January 2023. This review summarized the results of ROCK inhibitors in clinical and preclinical trials. In a clinical trial, various ROCK inhibitors improved CWH in individuals with open-angle glaucoma, cataract, iris cyst, ocular hypertension, and other ocular diseases. ROCK inhibitors also improved ocular wound healing by increasing cell adhesion, migration, and proliferation in vitro and in vivo. ROCK inhibitors have antifibrotic, antiangiogenic, anti-inflammatory, and antiapoptotic characteristics in CWH, according to the existing research. ROCK inhibitors were effective topical treatments for corneal infections. Ripasudil, Y-27632, H-1152, Y-39983, and AMA0526 are a few new ROCK inhibitors that may help CWH and replace human donor tissue. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the vasorelaxation effect of ripasudil (K-115), a novel Rho-associated coiled-coil-containing protein kinase (ROCK) inhibitor, on isolated retinal arterioles. We determined whether the actions of ripasudil on the retinal microvascular diameter were dependent on the endothelium and/or potassium channels in the smooth muscle, with the goals of uncovering the signaling mechanisms required for this vasomotor activity and inhibiting the action of endothelin-1 (ET-1). Methods: In this in vitro study, we isolated porcine retinal arterioles, which were cannulated and pressurized without flow. We recorded diametric changes using videomicroscopic techniques. Results: In a dose-dependent (10 nM-30 μM) manner, retinal arterioles were relaxed in response to ripasudil [maximum % resting diameter, 160.3% ± 7.7% (mean ± standard error of the mean)]. The ripasudil-induced vasorelaxation was unaffected by endothelium removal, using nonselective potassium channel blocker tetraethylammonium, Ca2+-activated large-conductance potassium channel blocker iberiotoxin, voltage-gated potassium channel blocker 4-AP, ATP-sensitive potassium channel blocker glibenclamide, and inward rectifier potassium channel blocker BaCl2. Ripasudil prevented ET-1-caused vasoconstriction of the retinal arterioles regardless of the presence of endothelium to a similar extent. Conclusion: The ROCK inhibitor ripasudil elicits endothelium-independent relaxation and inhibits the action of ET-1 on the retinal arterioles. Determining the relaxation properties of ripasudil on the retinal microvasculature will likely support the development of potential therapies for glaucoma. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate efficacy and safety of ripasudil for 1 year in addition to or replacing existing treatment regimens. Methods: We retrospectively reviewed the medical records for 128 eyes of 128 glaucoma patients who were prescribed ripasudil as an addition to or a switch from their preexisting antiglaucoma instillations. We investigated the rate and factors for discontinuation and intraocular pressure (IOP) reduction. Results: Almost half of the patients (60 eyes) discontinued ripasudil treatment before the 1 year mark, while remaining patients completed the treatment. The lack of efficacy and development of adverse effects were significantly correlated with discontinuation (P < 0.001) in the Cox proportional hazards model. In the Kaplan-Meier curve, adverse effects occurred in earlier phase and almost 60% dropped out within 3 months after ripasudil administration. However, adverse effects also occurred randomly throughout the study period. In patients who continued ripasudil, the mean IOPs (mmHg) at baseline, 6 and 12 months after treatment were 17.7 ± 5.1, 14.6 ± 5.0, and 14.8 ± 3.8 in the Addition group, and 17.8 ± 4.1, 15.4 ± 3.2, and 15.4 ± 5.0 in the Switch group, respectively (all P values <0.05). Conclusions: Almost half of the patients discontinued ripasudil owing to the lack of efficacy and the generation of adverse effects within the 1 year. In the remaining half, the addition and switching of ripasudil to the existing glaucoma treatment effectively reduced IOP for 1 year. [ABSTRACT FROM AUTHOR]

Purpose: Rho-associated kinase-inhibitor ripasudil 0.4% eye drops are reportedly effective for the reduction of intraocular pressure (IOP) in glaucoma patients. However, the previous studies investigated the efficacy of IOP reduction for only about 1 year. Here, we evaluated the safety and efficacy of long-term ripasudil instillation in Japanese open-angle glaucoma (OAG) patients. Methods: This study involved 312 eyes of 312 Japanese OAG patients newly initiated with ripasudil treatment at Kyoto Prefectural University of Medicine and Oike-Ikeda Eye Clinic, Kyoto, Japan. In all patients, adverse events leading to discontinuation of ripasudil treatment were investigated. Of the 312 patients, 129 patients able to continue ripasudil administration for over 12-months post-treatment initiation were enrolled to investigate the long-term efficacy. IOP data at 0-, 1-, 3-, 6-, 12-, 18-, and 24-months post initiation of continuous ripasudil use were obtained, and the IOP values at each time point were then compared. The first period (from 1-6 months) and second period (from 12-24 months) IOP data were also compared based on the mixed model. Results: IOP at each time-point post-treatment initiation was significantly reduced compared with that at pre initiation (P < 0.05). Differences in IOP between the first and second periods of the study were not statistically significant (P = 0.058). Adverse events leading to discontinuation of treatment included blepharitis (15.7%) and conjunctival hyperemia (9.0%). Conclusions: We found that in Japanese OAG patients, 24-month ripasudil eye drop instillation is both safe and effective for lowering IOP and that blepharitis is the primary adverse event for discontinuation of use. [ABSTRACT FROM AUTHOR]

Purpose: To determine how the Rho kinase inhibitor, ripasudil, affects metabolic function and cell viability in donor human corneal endothelial cells (HCECs).Methods: Endothelial cell-Descemet membrane (EDM) tissues were treated with 10 μM ripasudil and assayed for mitochondrial and glycolytic activity using extracellular flux analysis and then compared to untreated controls. In addition, EDM tissues with a 24-h ripasudil treatment and control tissues were exposed to 1 μM staurosporine to induce apoptosis and then analyzed for cell viability using apoptosis and necrosis assays.Results: Mitochondrial respiration metrics, specifically maximal respiration (P = 0.758) and spare respiratory capacity (P = 0.777), did not differ among the 1-h ripasudil treatment, 24-h treatment, and untreated tissues. Glycolytic activity assays showed an increase in glycolytic capacity at 1 h compared to the 24-h exposure group (P = 0.049) and controls (P = 0.009). Following exposure to staurosporine, the percentage of apoptotic HCECs was lower (P = 0.009) in ripasudil-treated tissues (2.473%, standard error of the mean [SEM] 0.477%) compared to untreated controls (3.349%, SEM 0.566%). In contrast, the percentage of necrotic HCECs decreased but did not differ statistically (P = 0.158) between ripasudil-treated (3.789%, SEM 0.487%) and untreated (4.567%, SEM 0.571%) tissues.Conclusions: Exposures to ripasudil did not result in any detectable reduction in metabolic function for HCECs in an ex vivo donor tissue model, and an increase in glycolytic activity at the 1-h time point was detected. In addition, HCECs treated with ripasudil gained a protective effect against induced apoptosis, suggesting that ripasudil may help improve the integrity of the corneal endothelium. [ABSTRACT FROM AUTHOR]