ROCK Inhibition Promotes Attachment, Proliferation, and Wound Closure in Human Embryonic Stem Cell-Derived Retinal Pigmented Epithelium

[Rho kinase inhibitor Y27632 promotes survival of human induced pluripotent stem cells during differentiation into functional midbrain dopaminergic progenitor cells in vitro]

OBJECTIVE

To improve the efficiency of induced differentiation of primitive neural epithelial cells derived from human induced pluripotent stem cells (hiPSCs-NECs) into functional midbrain dopaminergic progenitor cells (DAPs).

METHODS

HiPSCs were cultured in mTeSRTM medium containing DMH1 (10 μmol/L), SB431542 (10 μmol/L), SHH (200 ng/mL), FGF8 (100 ng/mL), purmorphamine (2 μmol/L), CHIR99021 (3 μmol/L), and N2 (1%) for 12 days to induce their differentiation into primitive neuroepithelial cells (NECs). The hiPSCs-NECs were digested with collagenase Ⅳ and then cultured in neurobasal medium supplemented with 1% N2, 2% B27-A, BDNF (10 ng/mL), GDNF (10 ng/mL), AA, TGF-β, cAMP, and 1% GlutaMax in the presence of different concentrations of Rho kinase inhibitor Y27632, and the culture medium was changed the next day to remove Y27632. Continuous induction was performed until day 28 to obtain DAPs.

RESULTS

Human iPSCs expressed the pluripotency markers OCT4, SOX2, Nanog, and SSEA1 and were positive for alkaline phosphatase staining. The hiPSCs-NECs were obtained on day 13 in the form of neural rosettes expressing neuroepithelial markers SOX2, nestin, and PAX6. In digested hiPSCs-NECs, the addition of 5 μmol/L Y27632 significantly promoted survival of the adherent cells, increased cell viability and the proportion of S-phase cells (P < 0.01), and reduced the rate of apoptotic cells (P < 0.05). On day 28 of induction, the obtained cells highly expressed the specific markers of DAPS (TH, FOXA2, NURR1, and Tuj1).

CONCLUSION

Treatment with Y27632 (5 μmol/L) for 24 h significantly promotes the survival of human iPSCs-NECs during their differentiation into DPAs without affecting the cell differentiation, which indirectly enhances the efficiency of cell differentiation.

Highly-expressed lncRNA FOXD2-AS1 in adipose mesenchymal stem cell derived exosomes affects HaCaT cells via regulating miR-185-5p/ROCK2 axis

The healing of skin wounds is a highly coordinated multi-step process that occurs after trauma including surgical incisions, thermal burns, and chronic ulcers. In this study, the authors investigated lncRNA FOXD2-AS1 function in adipose mesenchymal exosomes from ADMSCs that were successfully extracted. Highly expressed lncRNA FOXD2-AS1 in ADMSCs-exosomes accelerated HaCaT cell migration and proliferation. LncRNA FOXD2-AS1 negatively targeted miR-185-5p, and miR-185-5p negatively targeted ROCK2. Highly expressed lncRNA FOXD2-AS1 in ADMSCs-exosomes promoted HaCaT cell migration and proliferation via down-regulating miR-185-5p and further up-regulating ROCK2. In conclusion, LncRNA FOXD2-AS1 overexpression in ADMSCs derived exosomes might accelerate HaCaT cell migration and proliferation via modulating the miR-185-5p/ROCK2 axis.

The non-selective Rho-kinase inhibitors Y-27632 and Y-33075 decrease contraction but increase migration in murine and human hepatic stellate cells

BACKGROUND

The Rho-kinase ROCK II plays a major role in the activation of hepatic stellate cells (HSC), which are the key profibrotic and contractile cells contributing to the development of chronic liver disease. Inhibition of ROCK II ultimately blocks the phosphorylation of the myosin light chain (MLC) and thus inhibits stress fibre assembly and cell contraction. We investigated the effects of the ROCK inhibitors Y-33075 as well as Y-27632 in murine and human hepatic stellate cells.

METHODS

Primary isolated HSC from FVB/NJ mice and the immortalized human HSC line TWNT-4 were culture-activated and incubated with Y-27632 and Y-33075 (10nM to 10μM) for 24h. Protein expression levels were analyzed by Western Blots and transcriptional levels of pro-fibrotic markers and proliferative markers were evaluated using real-time qPCR. Migration was investigated by wound-healing assay. Proliferation was assessed by BrdU assay. Contraction of HSC was measured using 3D collagen matrices after incubation with Y-27632 or Y-33075 in different doses.

RESULTS

Both Rho-kinase inhibitors, Y-27632 and Y-33075, reduced contraction, fibrogenesis and proliferation in activated primary mouse HSC (FVB/NJ) and human HSC line (TWNT-4) significantly. Y-33075 demonstrated a 10-times increased potency compared to Y-27632. Surprisingly, both inhibitors mediated a substantial and unexpected increase in migration of HSC in FVB/NJ.

CONCLUSION

ROCK inhibition by the tested compounds decreased contraction but increased migration. Y-33075 proved more potent than Y27632 in the inhibition of contraction of HSCs and should be further evaluated in chronic liver disease.

Effect of Rho-Associated Kinase Inhibitor on Growth Behaviors of Human Induced Pluripotent Stem Cells in Suspension Culture

Rho-associated protein kinase (ROCK) inhibitors are used for the survival of single-dissociated human induced pluripotent stem cells (hiPSCs); however, their effects on the growth behaviors of hiPSCs in suspension culture are unexplored. Therefore, we investigated the effect of ROCK inhibitor on growth behaviors of two hiPSC lines (Tic and 1383D2) with different formation of aggregate that attached between single cells in suspension culture. The apparent specific growth rate by long-term exposure to Y-27632, a ROCK inhibitor, was maintained throughout the culture. Long-term exposure to ROCK inhibitor led to an increase in cell division throughout the culture in both lines. Immunofluorescence staining confirmed that hiPSCs forming spherical aggregates showed localization of collagen type I on its periphery. In addition, phosphorylated myosin (pMLC) was localized at the periphery in culture under short-term exposure to ROCK inhibitor, whereas pMLC was not detected at whole the aggregate in culture under long-term exposure. Scanning electron microscopy indicated that long-term exposure to ROCK inhibitor blocked the structural alteration on the surface of cell aggregates. These results indicate that pMLC inhibition by long-term ROCK inhibition leads to enhanced growth abilities of hiPSCs in suspension culture by maintaining the structures of extracellular matrices.

Dynamic full-field optical coherence tomography allows live imaging of retinal pigment epithelium stress model

Retinal degenerative diseases lead to the blindness of millions of people around the world. In case of age-related macular degeneration (AMD), the atrophy of retinal pigment epithelium (RPE) precedes neural dystrophy. But as crucial as understanding both healthy and pathological RPE cell physiology is for those diseases, no current technique allows subcellular in vivo or in vitro live observation of this critical cell layer. To fill this gap, we propose dynamic full-field OCT (D-FFOCT) as a candidate for live observation of in vitro RPE phenotype. In this way, we monitored primary porcine and human stem cell-derived RPE cells in stress model conditions by performing scratch assays. In this study, we quantified wound healing parameters on the stressed RPE, and observed different cell phenotypes, displayed by the D-FFOCT signal. In order to decipher the subcellular contributions to these dynamic profiles, we performed immunohistochemistry to identify which organelles generate the signal and found mitochondria to be the main contributor to D-FFOCT contrast. Altogether, D-FFOCT appears to be an innovative method to follow degenerative disease evolution and could be an appreciated method in the future for live patient diagnostics and to direct treatment choice.

Dynamic full-field optical coherence tomography (D-FFOCT) is used for live cell imaging of primary porcine retinal pigment epithelium (ppRPE) cultures and human induced pluripotent stem cell-derived RPE (hiRPE) cultures, allowing non-invasive realtime access to organelles and cytoskeleton dynamics in RPE cells.

Effectively Intervening Epithelial-Mesenchymal Transition of Retinal Pigment Epithelial Cells With a Combination of ROCK and TGF-β Signaling Inhibitors

Purpose

Epithelial-mesenchymal transition (EMT) of retinal pigment epithelial (RPE) cells is a key pathological event in proliferative retinal diseases such as proliferative vitreoretinopathy (PVR). This study aimed to explore a new method to reverse EMT in RPE cells to develop an improved therapy for proliferative retinal diseases.

Methods

In vitro, human embryonic stem cell-derived RPE cells were passaged and cultured at low density for an extended period of time to establish an EMT model. At different stages of EMT after treatment with known molecules or combinations of molecules, the morphology was examined, transepithelial electrical resistance (TER) was measured, and expression of RPE- and EMT-related genes were examined with RT-PCR, Western blotting, and immunofluorescence. In vivo, a rat model of EMT in RPE cells was established via subretinal injection of dispase. Retinal function was examined by electroretinography (ERG), and retinal morphology was examined.

Results

EMT of RPE cells was effectively induced by prolonged low-density culture. After EMT occurred, only the combination of the Rho-associated coiled-coil containing protein kinase (ROCK) inhibitor Y27632 and the TGF-β receptor inhibitor RepSox (RY treatment) effectively suppressed and reversed the EMT process, even in cells in an intermediate state of EMT. In dispase-treated Sprague-Dawley rats, RY treatment maintained the morphology of RPE cells and the retina and preserved retinal function.

Conclusions

RY treatment might promote mesenchymal-epithelial transition (MET), the inverse process of EMT, to maintain the epithelial-like morphology and function of RPE cells. This combined RY therapy could be a new strategy for treating proliferative retinal diseases, especially those involving EMT of RPE cells.

Transcriptome Landscape of Epithelial to Mesenchymal Transition of Human Stem Cell-Derived RPE

Purpose

RPE injury often induces epithelial to mesenchymal transition (EMT). Although RPE-EMT has been implicated in a variety of retinal diseases, including proliferative vitroretinopathy, neovascular and atrophic AMD, and diabetic retinopathy, it is not well-understood at the molecular level. To contribute to our understanding of EMT in human RPE, we performed a time-course transcriptomic analysis of human stem cell-derived RPE (hRPE) monolayers induced to undergo EMT using 2 independent, yet complementary, model systems.

Methods

EMT of human stem cell-derived RPE monolayers was induced by either enzymatic dissociation or modulation of TGF-β signaling. Transcriptomic analysis of cells at different stages of EMT was performed by RNA-sequencing, and select findings were confirmed by reverse transcription quantitative PCR and immunostaining. An ingenuity pathway analysis (IPA) was performed to identify signaling pathways and regulatory networks associated with EMT.

Results

Proteocollagenolytic enzymatic dissociation and cotreatment with TGF-β and TNF-α both induce EMT in human stem cell-derived RPE monolayers, leading to an increased expression of mesenchymal factors and a decreased expression of RPE differentiation-associated factors. Ingenuity pathway analysis identified the upstream regulators of the RPE-EMT regulatory networks and identified master switches and nodes during RPE-EMT. Of particular interest was the identification of widespread dysregulation of axon guidance molecules during RPE-EMT progression.

Conclusions

The temporal transcriptome profiles described here provide a comprehensive resource of the dynamic signaling events and the associated biological pathways that underlie RPE-EMT onset. The pathways defined by these studies may help to identify targets for the development of novel therapeutic targets for the treatment of retinal disease.

A ROCK Inhibitor Promotes Graft Survival during Transplantation of iPS-Cell-Derived Retinal Cells

Currently, retinal pigment epithelium (RPE) transplantation includes sheet and single-cell transplantation, the latter of which includes cell death and may be highly immunogenic, and there are some issues to be improved in single-cell transplantation. Y-27632 is an inhibitor of Rho-associated protein kinase (ROCK), the downstream kinase of Rho. We herein investigated the effect of Y-27632 in vitro on retinal pigment epithelium derived from induced pluripotent stem cells (iPS-RPE cells), and also its effects in vivo on the transplantation of iPS-RPE cell suspensions. As a result, the addition of Y-27632 in vitro showed suppression of apoptosis, promotion of cell adhesion, and higher proliferation and pigmentation of iPS-RPE cells. Y-27632 also increased the viability of the transplant without showing obvious retinal toxicity in human iPS-RPE transplantation into monkey subretinal space in vivo. Therefore, it is possible that ROCK inhibitors can improve the engraftment of iPS-RPE cell suspensions after transplantation.

Thermoresponsive GenisteinNLC-dexamethasone-moxifloxacin multi drug delivery system in lens capsule bag to prevent complications after cataract surgery

Cataract surgery is the most common intraocular procedure. To decrease postsurgical inflammation, prevent infection and reduce the incidence of secondary cataract, we built a temperature-sensitive drug delivery system carrying dexamethasone, moxifloxacin and genistein nanostructured lipid carrier (GenNLC) modified by mPEG-PLA based on F127/F68 as hydrogel. Characterizations and release profiles of the drug delivery system were studied. In vitro functions were detected by CCK-8 test, immunofluorescence, wound-healing assay, real time-PCR and western blotting. The size of GenNLCs was 39.47 ± 0.69 nm in average with surface charges of - 4.32 ± 0.84 mV. The hydrogel gelation temperature and time were 32 °C, 20 s with a viscosity, hardness, adhesiveness and stringiness of 6.135 Pa.s, 54.0 g, 22.0 g, and 3.24 mm, respectively. Transmittance of the gel-release medium was above 90% (93.44 ± 0.33% to 100%) at range of 430 nm to 800 nm. Moxifloxacin released completely within 10 days. Fifty percent of dexamethasone released at a constant rate in the first week, and then released sustainably with a tapering down rate until day 30. Genistein released slowly but persistently with a cumulative release of 63% at day 40. The thermoresponsive hydrogel inhibited the proliferation, migration and epithelial-mesenchymal transition of SRA 01/04 cells, which were confirmed by testing CCK-8, wound-healing assay, western blot, real time-PCR (RT-PCR) and immunofluorescence. These results support this intracameral thermoresponsive in situ multi-drug delivery system with programmed release amounts and release profiles to cut down the need of eye drops for preventing inflammation or infection and to reduce posterior capsular opacification following cataract surgery.

Integrin: Basement membrane adhesion by corneal epithelial and endothelial cells

Integrins mediate adhesion of cells to substrates and maintain tissue integrity by facilitating mechanotransduction between cells, the extracellular matrix, and gene expression in the nucleus. Changes in integrin expression in corneal epithelial cells and corneal endothelial cells impacts their adhesion to the epithelial basement membrane (EpBM) and Descemet's membrane, respectively. Integrins also play roles in assembly of basement membranes by both activating TGFβ1 and other growth factors. Over the past two decades, this knowledge has been translated into methods to grow corneal epithelial and endothelial cells in vitro for transplantation in the clinic thereby transforming clinical practice and quality of life for patients. Current knowledge on the expression and function of the integrins that mediate adhesion to the basement membrane expressed by corneal epithelial and endothelial cells in health and disease is summarized. This is the first review to discuss similarities and differences in the integrins expressed by both cell types.

Forces during cellular uptake of viruses and nanoparticles at the ventral side

Many intracellular pathogens, such as mammalian reovirus, mimic extracellular matrix motifs to specifically interact with the host membrane. Whether and how cell-matrix interactions influence virus particle uptake is unknown, as it is usually studied from the dorsal side. Here we show that the forces exerted at the ventral side of adherent cells during reovirus uptake exceed the binding strength of biotin-neutravidin anchoring viruses to a biofunctionalized substrate. Analysis of virus dissociation kinetics using the Bell model revealed mean forces higher than 30 pN per virus, preferentially applied in the cell periphery where close matrix contacts form. Utilizing 100 nm-sized nanoparticles decorated with integrin adhesion motifs, we demonstrate that the uptake forces scale with the adhesion energy, while actin/myosin inhibitions strongly reduce the uptake frequency, but not uptake kinetics. We hypothesize that particle adhesion and the push by the substrate provide the main driving forces for uptake.

Many intracellular pathogens mimic extracellular matrix motifs to specifically interact with the host membrane which may influences virus particle uptake. Here authors use single molecule tension sensors to reveal the minimal forces exerted on single virus particles and demonstrate that the uptake forces scale with the adhesion energy.

ROCK inhibitor increases proacinar cells in adult salivary gland organoids

Salisphere-derived adult epithelial cells have been used to improve saliva production of irradiated mouse salivary glands. Importantly, optimization of the cellular composition of salispheres could improve their regenerative capabilities. The Rho Kinase (ROCK) inhibitor, Y27632, has been used to increase the proliferation and reduce apoptosis of progenitor cells grown in vitro. In this study, we investigated whether Y27632 could be used to improve expansion of adult submandibular salivary epithelial progenitor cells or to affect their differentiation potential in different media contexts. Application of Y27632 in medium used previously to grow salispheres promoted expansion of Kit⁺ and Mist1⁺ cells, while in simple serum-containing medium Y27632 increased the number of cells that expressed the K5 basal progenitor marker. Salispheres derived from Mist1^CreERT2; R26^TdTomato mice grown in salisphere media with Y27632 included Mist1-derived cells. When these salispheres were incorporated into 3D organoids, inclusion of Y27632 in the salisphere stage increased the contribution of Mist1-derived cells expressing the proacinar/acinar marker, Aquaporin 5 (AQP5), in response to FGF2-dependent mesenchymal signals. Optimization of the cellular composition of salispheres and organoids can be used to improve the application of adult salivary progenitor cells in regenerative medicine strategies.

ROCK Inhibitor-Induced Promotion of Retinal Pigment Epithelial Cell Motility during Wound Healing

Purpose

No standard therapy for RPE tear, a complication of neovascular age-related macular degeneration, exists even though RPE tears cause severe vision loss, and promotion of cell proliferation and/or migration could be a candidate RPE tear therapy. The aim of this study is to evaluate the effect of Rho-associated coiled-coil containing kinase (ROCK) inhibitor Y27632 on retinal pigment epithelial (RPE) cell motility during wound healing.

Methods

Human RPE cells were cultured in media with and without 10 μM Y27632. A luminescent cell viability assay and vinculin immunocytochemistry were used to test the Y27632 effect on RPE cell adhesion. The mean size of vinculin puncta was quantified from immunofluorescence images. RPE cell motility during wound healing was evaluated using time-lapse imaging and measuring cell migration distances and cell coverage rate in wound fields.

Results

The number of adhered RPE and mean size of vinculin puncta were, respectively, 20519 cells and 3.65 μm² under nontreatment and 23569 cells and 0.66 μm² under Y27632 treatment. Cell migration distance and cell coverage percentage for untreated and Y27632-treated cells were 98.9 and 59.4% and 203.4 and 92.5%, respectively.

Conclusions

Inhibition of ROCK signaling by using 10 μM Y27632 promoted RPE cell motility during wound healing by reducing RPE cell adhesion strength.

Rho kinase inhibitors-a review on the physiology and clinical use in Ophthalmology

The Rho kinase (ROCK) signaling pathway is involved in several cellular events that include cell proliferation and cytoskeleton modulation leading to cell adhesion. The ROCK pathway in the human eye has been hypothesized to play important roles in corneal endothelial cell physiology and pathologic states. In addition, ROCK signaling has been identified as an important regulator of trabecular meshwork (TM) outflow, which is altered in glaucomatous eyes. These roles in corneal and glaucomatous disease states have led to the growing interest in the development of drugs selectively targeting this pathway (ROCK inhibitors). The authors provide a review of the literature on the pathobiology of the ROCK signaling in corneal endothelial disease, glaucoma, and vitreoretinal disease, as well as the clinical usefulness of ROCK inhibitors in Ophthalmology.

Wound healing of human embryonic stem cell-derived retinal pigment epithelial cells is affected by maturation stage

Background

Wound healing of retinal pigment epithelium (RPE) is a complex process that may take place in common age-related macular degeneration eye disease. The purpose of this study was to evaluate whether wounding and wound healing has an effect on Ca²⁺ dynamics in human embryonic stem cell (hESC)-RPEs cultured different periods of time.

Methods

The 9-day-cultured or 28-day-cultured hESC-RPEs from two different cell lines were wounded and the dynamics of spontaneous and mechanically induced intracellular Ca²⁺ activity was measured with live-cell Ca²⁺ imaging either immediately or 7 days after wounding. The healing time and speed were analyzed with time-lapse bright field microscopy. The Ca²⁺ activity and healing speed were analysed with image analysis. In addition the extracellular matrix deposition was assessed with confocal microscopy.

Results

The Ca²⁺ dynamics in hESC-RPE monolayers differed depending on the culture time: 9-day-cultured cells had higher number of cells with spontaneous Ca²⁺ activity close to freshly wounded edge compared to control areas, whereas in 28-day-cultured cells there was no difference in wounded and control areas. The 28-day-cultured, wounded and 7-day-healed hESC-RPEs produced wide-spreading intercellular Ca²⁺ waves upon mechanical stimulation, while in controls propagation was restricted. Most importantly, both wave spreading and spontaneous Ca²⁺ activity of cells within the healed area, as well as the cell morphology of 28-day-cultured, wounded and thereafter 7-day-healed areas resembled the 9-day-cultured hESC-RPEs.

Conclusions

This acquired knowledge about Ca²⁺ dynamics of wounded hESC-RPE monolayers is important for understanding the dynamics of RPE wound healing, and could offer a reliable functionality test for RPE cells. The data presented in here suggests that assessment of Ca²⁺ dynamics analysed with image analysis could be used as a reliable non-invasive functionality test for RPE cells.

Electronic supplementary material

The online version of this article (10.1186/s12938-018-0535-z) contains supplementary material, which is available to authorized users.

Myosin phosphatase accelerates cutaneous wound healing by regulating migration and differentiation of epidermal keratinocytes via Akt signaling pathway in human and murine skin

Wound healing is a complex sequence of cellular and molecular processes such as inflammation, cell migration, proliferation and differentiation. ROCK is a widely investigated Ser/Thr kinase with important roles in rearranging the actomyosin cytoskeleton. ROCK inhibitors have already been approved to improve corneal endothelial wound healing. The purpose of this study was to investigate the functions of myosin phosphatase (MP or PPP1CB), a type-1 phospho-Ser/Thr-specific protein phosphatase (PP1), one of the counter enzymes of ROCK, in skin homeostasis and wound healing. To confirm our hypotheses, we applied tautomycin (TM), a selective PP1 inhibitor, on murine skin that caused the arrest of wound closure. TM suppressed scratch closure of HaCaT human keratinocytes without having influence on the survival of the cells. Silencing of, the regulatory subunit of MP (MYPT1 or PPP1R12A), had a negative impact on the migration of keratinocytes and it influenced the cell-cell adhesion properties by decreasing the impedance of HaCaT cells. We assume that MP differentially activates migration and differentiation of keratinocytes and plays a key role in the downregulation of transglutaminase-1 in lower layers of skin where no differentiation is required. MAPK Proteome Profiler analysis on human ex vivo biopsies with MYPT1-silencing indicated that MP contributes to the mediation of wound healing by regulating the Akt signaling pathway. Our findings suggest that MP plays a role in the maintenance of normal homeostasis of skin and the process of wound healing.