We evaluated whether LIM-kinase 2 inhibitor (LIMK2i) could improve erectile function by suppressing corporal fibrosis through the normalization of the Rho-associated coiled-coil protein kinase 1 (ROCK1)/LIMK2/Cofilin pathway in a rat model of cavernous nerve crush injury (CNCI). Sixty 11-week-old male Sprague-Dawley rats were divided equally into five groups: sham surgery (S), CNCI (I), and CNCI treated with low-dose (L), medium-dose (M), and high-dose (H) LIMK2i. The L, M, and H groups were treated with a daily intraperitoneal injection of LIMK2i (2.5, 5.0, and 10.0 mg kg^-1 body weight, respectively) for 1 week after surgery. The erectile response was assessed using electrostimulation at 1 week, postoperatively. Penile tissues were processed for Masson's trichrome staining, double immunofluorescence, and Western blot assay. Erectile responses in the H group improved compared with the I group, while the M group showed only partial improvement. A significantly decreased smooth muscle/collagen ratio and an increased content of fibroblasts positive for phospho-LIMK2 were noted in the I group. The M and H groups revealed significant improvements in histological alterations and the dysregulated LIMK2/Cofilin pathway, except for LIMK2 phosphorylation in the M group. The inhibition of LIMK2 did not affect the ROCK1 protein expression. The content of fibroblasts positive for phospho-LIMK2 in the H group returned to the level found in the S group, whereas it did not in the M group. However, the L group did not exhibit such improvements. Our data suggest that the inhibition of LIMK2, particularly with administration of 10.0 mg kg^-1 body weight LIMK2i, can improve corporal fibrosis and erectile function by normalizing the LIMK2/Cofilin pathway.
Animals ; Cofilin 1/metabolism* ; Electric Stimulation ; Erectile Dysfunction/etiology* ; Fibroblasts/pathology* ; Fibrosis/drug therapy* ; Lim Kinases/antagonists & inhibitors* ; Male ; Penile Diseases/drug therapy* ; Penis/innervation* ; Peripheral Nerve Injuries/pathology* ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; Signal Transduction/drug effects* ; rho-Associated Kinases/genetics*

PURPOSE: Increased lipoprotein-associated phospholipase A2 (Lp-PLA2) activity and Rho kinase activity may be associated with atherosclerosis. The principal aim of this study was to examine whether darapladib (a selective Lp-PLA2 inhibitor) could reduce the elevated Lp-PLA2 and Rho kinase activity in atherosclerosis. MATERIALS AND METHODS: Studies were performed in male Sprague-Dawley rats. The atherosclerosis rats were prepared by feeding them with a high-cholesterol diet for 10 weeks. Low-dose darapladib (25 mg.kg-1.d-1) and high-dose darapladib (50 mg.kg-1.d-1) interventions were then administered over the course of 2 weeks. RESULTS: The serum levels of triglycerides, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), high-sensitivity C-reactive protein (hs-CRP), and Lp-PLA2, significantly increased in atherosclerosis model groups, as did Rho kinase activity and cardiomyocyte apoptosis (p<0.05 vs. sham group), whereas nitric oxide (NO) production was reduced. Levels of TC, LDL-C, CRP, Lp-PLA2, and Rho kinase activity were respectively reduced in darapladib groups, whereas NO production was enhanced. When compared to the low-dose darapladib group, the reduction of the levels of TC, LDL-C, CRP, and Lp-PLA2 was more prominent in the high-dose darapladib group (p<0.05), and the increase of NO production was more prominent (p<0.05). Cardiomyocyte apoptosis of the high-dose darapladib group was also significantly reduced compared to the low-dose darapladib group (p<0.05). However, there was no significant difference in Rho kinase activity between the low-dose darapladib group and the high-dose darapladib group (p>0.05). CONCLUSION: Darapladib, a Lp-PLA2 inhibitor, leads to cardiovascular protection that might be mediated by its inhibition of both Rho kinase and Lp-PLA2 in atherosclerosis.
1-Alkyl-2-acetylglycerophosphocholine Esterase/*antagonists & inhibitors/blood/drug effects ; Animals ; Atherosclerosis/blood/*drug therapy/*enzymology ; *Benzaldehydes ; C-Reactive Protein/metabolism ; Cholesterol/blood ; Cholesterol, HDL/blood ; Cholesterol, LDL/blood ; Dose-Response Relationship, Drug ; Male ; *Oximes ; Phospholipase A2 Inhibitors/*administration & dosage/adverse effects ; Rats ; Rats, Sprague-Dawley ; Triglycerides/blood ; rho-Associated Kinases/*metabolism

ObjectiveTo investigate the potential role of the RhoA/Rock signaling pathway in the formation of prostate cancer and the effects of the Rock inhibitor fasudil on the invasion, migration and apoptosis of human prostate cancer cells.

METHODSHuman prostate cancer cell lines PC3 and DU145 were treated with fasudil at the concentrations of 5, 10, 20, 40, 80, and 160 μmol/L, respectively, and those as negative controls cultured in the Ham's-F12 medium, all for 24 hours. Then, MTT assay was used to measure the cell inhibition rate and half maximal inhibitory concentration (IC50) value of fasudil, with 1/4 of IC50 as the medication dose for further investigation. The expressions of RhoA, RockⅠ, and RockⅡ proteins in the PC3 and DU145 cells were detected by Western blot and immunohistochemistry, and the invasion, migration and apoptosis of the cells were determined using the Transwell chamber, scratch wound healing assay and flow cytometry.

RESULTSFasudil inhibited the proliferation of the PC3 cells from (9.29±1.23)% at 5 μmol/L to (81.37±3.97)% at 160 μmol/L and that of DU145 from (7.59±1.54)% to (76.53±2.67)%, both in a dose-dependent manner (P<0.05 ). Significantly fewer PC3 and DU145 cells migrated into the lower compartment in the experimental group (39.2±8.4 and 34.2±6.7) than in the negative control (116.8±9.3 and 112.5±10.8) (P<0.05 ). The wound healing rates of the PC3 and DU145 cells were remarkably lower in the former (［37.26±1.17］% and ［32.38±2.73］%) than in the latter (［78.12±4.16］% and ［69.47±6.71］%) (P<0.05 ). Annexin V-FITC/PI double staining showed markedly increased apoptosis rates of PC3 and DU145 cells treated with fasudil (［31.88±2.49］% and ［28.65±2.99］%) as compared with the negative controls (［7.51±2.28］% and ［7.13±1.61］%) (P<0.05 ). The expressions of RockⅠ and RockⅡ were significantly reduced in the fasudil-treated cells in comparison with those of the control group (P<0.05 ) while that of RhoA showed no significant difference between the two groups (P>0.05 ).

CONCLUSIONSThe RhoA/Rock signaling pathway may play an important role in the formation of prostate cancer. Fasudil can significantly inhibit the proliferation, migration, and invasion and promote the apoptosis of human prostate cancer PC3 and DU145 cells by reducing RhoA/Rho kinase activity.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine ; analogs & derivatives ; pharmacology ; Apoptosis ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Humans ; Male ; Prostatic Neoplasms ; drug therapy ; pathology ; Signal Transduction ; rho-Associated Kinases ; antagonists & inhibitors

Emerging evidence indicates that microglia activation plays an important role in spinal cord injury (SCI) caused by trauma. Studies have found that inhibiting the Rho/Rho-associated protein kinase (ROCK) signaling pathway can reduce inflammatory cytokine production by microglia. In this study, Western blotting was conducted to detect ROCK2 expression after the SCI; the ROCK Activity Assay kit was used for assay of ROCK pathway activity; microglia morphology was examined using the CD11b antibody; electron microscopy was used to detect microglia phagocytosis; TUNEL was used to detect tissue cell apoptosis; myelin staining was performed using an antibody against myelin basic protein (MBP); behavioral outcomes were evaluated according to the methods of Basso, Beattie, and Bresnahan (BBB). We observed an increase in ROCK activity and microglial activation after SCI. The microglia became larger and rounder and contained myelin-like substances. Furthermore, treatment with fasudil inhibited neuronal cells apoptosis, alleviated demyelination and the formation of cavities, and improved motor recovery. The experimental evidence reveals that the ROCK inhibitor fasudil can regulate microglial activation, promote cell phagocytosis, and improve the SCI microenvironment to promote SCI repair. Thus, fasudil may be useful for the treatment of SCI.
1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine ; analogs & derivatives ; pharmacology ; therapeutic use ; Animals ; Apoptosis ; Male ; Microglia ; drug effects ; metabolism ; Myelin Basic Protein ; metabolism ; Myelin Sheath ; metabolism ; Phagocytosis ; Protein Kinase Inhibitors ; pharmacology ; therapeutic use ; Rats ; Rats, Sprague-Dawley ; Spinal Cord Injuries ; drug therapy ; rho-Associated Kinases ; antagonists & inhibitors ; metabolism

BACKGROUNDHyperglycemia may accelerate liver fibrosis. Currently, there is no effective treatment for liver fibrosis induced by type 2 diabetes. The study aim was to investigate whether RhoA/Rho kinase (ROCK) pathway is involved in liver fibrosis in the rats with type 2 diabetes and define the protective effects of fasudil on livers.

METHODSA rat model of type 2 diabetes was established by high fat diet combined with streptozotocin (30 mg/kg, intraperitoneal injection). Animals were randomly assigned to 3 groups: control rats, untreated diabetic rats that received vehicle and fasudil-treated diabetic rats that received ROCK inhibitor fasudil hydrochloride hydrate (10 mg/kg per day, intraperitoneal injection, for 14 weeks). The morphological features of liver were observed by HE staining. Accumulation of collagen in livers was determined by Masson staining and the measurement of hydroxyproline. The mRNA expression of transforming growth factor-β1 (TGFβ1), connective tissue growth factor (CTGF), type-I, and type-III procollagen was assessed with real-time polymerase chain reaction. The phosphorylation of myosin phosphatase target subunit-1 (MYPT1) and the protein levels of TGFβ1 and α-smooth muscle actin (a-SMA) were evaluated by Western blotting.

RESULTSCompared with control rats, untreated diabetic rats showed higher values of collagen and hydroxyproline in livers (P < 0.01), the phosphorylation of MYPT1 and the protein levels of TGFβ1 and α-SMA were increased (P < 0.01), and the mRNA expression of TGFβ1, CTGF, type-I, and type-III procollagen was upregulated (P < 0.01); compared with untreated diabetic rats, treatment with fasudil signifcantly reduced values of collagen and hydroxyproline (P < 0.01), and decreased the phosphorylation of MYPT1 and the levels of TGFβ1 and α-SMA (P < 0.01), concomitant with the downregulation of TGFβ1/CTGF, type-I, and type-III procollagen mRNA expression (P < 0.01).

CONCLUSIONSFasudil ameliorates liver fibrosis in rats with type 2 diabetes at least partly by inhibiting TGFβ1/CTGF pathway and α-SMA expression. Inhibition of RhoA/ROCK may be a novel therapeutic target for liver fibrosis in diabetic non-alcoholic steatohepatitis.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine ; analogs & derivatives ; therapeutic use ; Animals ; Connective Tissue Growth Factor ; metabolism ; Diabetes Mellitus, Type 2 ; drug therapy ; Female ; Liver Cirrhosis ; drug therapy ; enzymology ; metabolism ; Protein Kinase Inhibitors ; therapeutic use ; Rats ; Rats, Sprague-Dawley ; Transforming Growth Factor beta1 ; metabolism ; rho-Associated Kinases ; antagonists & inhibitors

OBJECTIVETo study changes in paired-immunoglobulin-like receptor B (PirB) expression after hypoxic-ischemic brain damage (HIBD) as well as the role for targeted inhibition of PirB activity in nerve regeneration in rats.

METHODSNewborn Sprague-Dawleyrats rats were divided into: a sham operation group (n=30), a HIBD group (n=30), and an anti PirB antibody treatment group (n=6). In the HIBD group, HIBD was induced by right carotid artery ligature and subsequent exposure to hypoxia (8% O2) for 3 hours. In the sham operation group, right carotid artery was dissected as in the HIBD group but no ligature and hypoxic exposure was not applied. In the two groups, 6 animals were sacrificed at 0, 6, 12, 24 and 72 hours after the operation and hypoxic exposure. In the antibody treatment group, after carotid artery ligation and hypoxia exposure as in the HIBD group, an anti PirB antibody was injected intracerebrally and animals were sacrificed 72 hours after the injection. Immediately after sacrifice of the animals at designated time points, brain tissue specimens were collected. The presence and content of PirB protein were assessed by immunohistochemistry and Western blot analysis respectively, the abundance of PirB mRNA was determined by RT-PCR, and the Rho kinase (Rock) activity was determined by immunoprecipitation.

RESULTSAt 72 hours after operation, PirB mRNA abundance and protein content in the brain were significantly increased as compared with the measurements at 0 hour after operation in the HIBD group (P<0.05); ROCK activity was significantly increased in the HIBD group as compared with the sham operation and anti PirB antibody groups (P<0.05).

CONCLUSIONSPirB might be involved in HIBD through a Rho-ROCK-dependent mechanism and antibody-mediated neutralization of PirB in the brain may offer a novel therapeutic strategy for HIBD.

Animals ; Animals, Newborn ; Hypoxia-Ischemia, Brain ; physiopathology ; therapy ; Nerve Regeneration ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Receptors, Immunologic ; antagonists & inhibitors ; genetics ; physiology ; Signal Transduction ; rho-Associated Kinases ; metabolism

BACKGROUNDAfter injury, axonal regeneration of the adult central nervous system (CNS) is inhibited by myelin-derived growth-suppressing proteins. These axonal growth inhibitory proteins are mediated via activation of Rho, a small GTP-binding protein. The activated form of Rho, which is bound to GTP, is the direct activator of Rho kinase (ROCK) through serial downstream effector proteins to inhibit axonal regeneration. The objective of this study was to observe the therapeutic effect of inactivation of the Rho-ROCK signaling pathway to promote neurologic recovery after spinal cord injuries in rats.

METHODSOne hundred and twenty adult female Sprague-Dawley rats were randomly divided into three groups. Laminectomies alone were conducted in 40 rats in the sham group. Laminectomies and spinal cord transections were performed in 40 rats in the control group (treated with normal saline administered intraperitoneally). Laminectomies and spinal cord transections were performed in 40 rats in the fasudil-treated group (treated with fasudil administered intraperitoneally). Neurologic recovery was evaluated before surgery and 3 days, and 1, 2, 3, and 4 weeks after surgery using the Basso-Beattie-Bresnahan (BBB) scale of hind limb movement. At the same time, the expression of RhoA mRNA was determined with RT-PCR. Histopathologic examinations and immunofluorescence staining of NF were performed 1 month after surgery.

RESULTSCompared with the control group, the BBB scores of the fasudil-treated group were significantly increased and the expression of RhoA mRNA was significantly decreased. In the fasudil-treated group, a large number of NF-positive regenerating fibers was observed; some fibers crossed the slit of the lesion.

CONCLUSIONInactivation of the Rho-ROCK signaling pathway promotes CNS axonal regeneration and neurologic recovery after spinal cord injuries in rats.

Animals ; Female ; Fluorescent Antibody Technique ; Nerve Regeneration ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; physiology ; Spinal Cord Injuries ; pathology ; physiopathology ; psychology ; therapy ; rho-Associated Kinases ; antagonists & inhibitors ; physiology ; rhoA GTP-Binding Protein ; antagonists & inhibitors ; physiology

AIM: To investigate the effects of pinocembrin on angiotensin II (Ang II)-induced vascular contraction, and to explore its molecular mechanism of actions. METHODS: The isometric vascular tone was measured in rat thoracic aortic rings with denuded endothelium. Phosphorylation level of myosin phosphatase target unit 1 (MYPT1), and protein levels of Rho kinase 1 (ROCK1, ROKβ or p160ROCK) and angiotensin II type-1 receptor (AT1R) were determined by Western blot analysis. RESULTS: Pinocembrin produced a relaxant effect on endothelium-denuded aortic rings contracted by Ang II (100 nmol·L(-1)) in a dose-dependent manner. In endothelium-denuded aortic rings stimulated by Ang II, pretreatment with pinocembrin (25 and 100 μmol·L(-1)) for 20 min significantly attenuated MYPT1 phosphorylation and ROCK1 protein levels. Meanwhile, the protein level of AT1R in response to Ang II was not affected by pinocembrin in rat aortic rings. CONCLUSION These findings indicate that pinocembrin inhibits vasoconstriction induced by Ang II in rat endothelium-denuded aortic rings, and the mechanism at least in part, is due to the blockade of the RhoA/ROCK pathway.
Angiotensin II ; metabolism ; Animals ; Aorta ; drug effects ; enzymology ; metabolism ; physiopathology ; Flavanones ; pharmacology ; In Vitro Techniques ; Male ; Myocardial Contraction ; drug effects ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects ; Vasoconstriction ; drug effects ; rho-Associated Kinases ; antagonists & inhibitors ; genetics ; metabolism

Cinnamyl alcohol (CAL) is known as an antipyretic, and a recent study showed its vasodilatory activity without explaining the mechanism. Here we demonstrate the vasodilatory effect and the mechanism of action of CAL in rat thoracic aorta. The change of tension in aortic strips treated with CAL was measured in an organ bath system. In addition, vascular strips or human umbilical vein endothelial cells (HUVECs) were used for biochemical experiments such as Western blot and nitrite and cyclic guanosine monophosphate (cGMP) measurements. CAL attenuated the vasoconstriction of phenylephrine (PE, 1 microM)-precontracted aortic strips in an endothelium-dependent manner. CAL-induced vasorelaxation was inhibited by pretreatment with NG-nitro-L-arginine methyl ester (L-NAME; 10(-4) M), methylene blue (MB; 10(-5) M) and 1 H-[1,2,4]-oxadiazolole-[4,3-a] quinoxalin-10one, (ODQ; 10(-6) or 10(-7) M) in the endothelium-intact aortic strips. Atrial natriuretic peptide (ANP; 10(-8) or 10(-9) M) did not affect the vasodilatory effect of CAL. The phosphorylation of endothelial nitric oxide synthase (eNOS) and generation of nitric oxide (NO) were stimulated by CAL treatment in HUVECs and inhibited by treatment with L-NAME. In addition, cGMP and PKG1 activation in aortic strips treated with CAL were also significantly inhibited by L-NAME. Furthermore, CAL relaxed Rho-kinase activator calpeptin-precontracted aortic strips, and the vasodilatory effect of CAL was inhibited by the ATP-sensitive K+ channel inhibitor glibenclamide (Gli; 10(-5) M) and the voltage-dependent K+ channel inhibitor 4-aminopyridine (4-AP; 2 x 10(-4) M). These results suggest that CAL induces vasorelaxation by activating K+ channels via the NO-cGMP-PKG pathway and the inhibition of Rho-kinase.
Animals ; Aorta/drug effects/metabolism/physiology ; Atrial Natriuretic Factor/pharmacology ; Cyclic GMP/*metabolism ; Cyclic GMP-Dependent Protein Kinases/*metabolism ; Dipeptides/pharmacology ; Human Umbilical Vein Endothelial Cells/drug effects/metabolism ; Humans ; Male ; Methylene Blue/pharmacology ; NG-Nitroarginine Methyl Ester/pharmacology ; Nitric Oxide/*metabolism ; Nitric Oxide Synthase/metabolism ; Oxadiazoles/pharmacology ; Phenylephrine/pharmacology ; Phosphorylation ; Potassium Channel Blockers/pharmacology ; Potassium Channels/*agonists ; Propanols/*pharmacology ; Quinoxalines/pharmacology ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; Vasoconstriction/*drug effects ; Vasodilation/drug effects ; rho-Associated Kinases/antagonists & inhibitors/*metabolism

The aim of this study was to investigate the influence of endothelial like cells differentiated from rat bone marrow mesenchymal stem cells (rBMSC-ECs) on angiogenesis and the effect of Rho kinase (ROCK) inhibitor using an in vitro model of cells co-cultured with rat aorta ring. Cell proliferation capability was detected by MTT method. The rBMSC-ECs were co-cultured with rat aorta ring in rat tail collagen and endothelial medium. A ROCK specific inhibitor, HA-1077 at different concentrations (0, 10, 30 and 60 mmol/L, respectively) was added into the medium of ring-cell co-culture. The protein expression of ROCK I and ROCK II were detected by Western blot. On the third day of cultivation, the branch number of neogenetic microvessels increased by 34.5% in ring-cell co-culture group compared with that in simple aorta ring group (P < 0.01). Compared with that in ring-cell co-culture group, it was significantly decreased by 57.70%, 64.13% and 48.23% respectively in three concentrations of HA-1077 groups (all P < 0.01). However, on the sixth day, rBMSC-ECs proliferated and migrated to the nearby aorta ring, and the growth of microvessels became slow. On the ninth day, some of neogenetic microvessels were retracted, some became thicken, coarsen and lengthen, and some of rBMSC-ECs were sprouting and forming capillary like picture. The protein expression of ROCK I/II was slightly higher in ring-cell co-culture group than that in simple aorta ring group. But, in three concentrations of HA-1077 groups, it was slightly lower than that in ring-cell co-culture group. By using rhodamine-phalloidin staining and laser scanning confocal fluorescence microscope, it showed that there were a lot of the F-actin cytoskeletons in neogenesis microvessels of aorta ring, and there were a lot of thick and long stress fibers in the cells. F-actin-rich surface protrusions at the leading edge of the cell were also shown. Another ROCK inhibitor, Y-27632 (10 μmol/L) induced the actin cytoskeleton reorganization: F-actins appeared to be peripheral fibers at outer area of cell; stress fiber and filopodia disappeared. These results suggest that rBMSC-ECs themselves can be differentiated into new microvessels and facilitate angiogenesis when they are co-cultured with rat aorta ring. The mechanisms involve ROCK activation and F-actin cytoskeleton recombination.
1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine ; analogs & derivatives ; pharmacology ; Animals ; Aorta, Thoracic ; cytology ; Bone Marrow Cells ; cytology ; Cell Differentiation ; physiology ; Cells, Cultured ; Coculture Techniques ; Endothelial Cells ; cytology ; Male ; Mesenchymal Stromal Cells ; cytology ; Neovascularization, Physiologic ; physiology ; Rats ; Rats, Sprague-Dawley ; rho-Associated Kinases ; antagonists & inhibitors ; metabolism