Interaction between fasudil hydrochloride and bovine serum albumin: spectroscopic study

The interaction between fasudil hydrochloride (FSD) and bovine serum albumin (BSA) was investigated using fluorescence and ultraviolet spectroscopy under imitated physiological conditions. The Stern–Volmer quenching model has been successfully applied and the results revealed that FSD could quench the intrinsic fluorescence of BSA effectively via static quenching. The binding constants and binding sites for the BSA–FSD system were evaluated. The corresponding thermodynamic parameters obtained at different temperatures indicated that hydrophobic force played a major role in the interaction of FSD and BSA. The distance between the donor (BSA) and the acceptor (FSD) was obtained according to fluorescence resonance energy transfer (FRET). Synchronous fluorescence spectroscopy and FT‐IR spectra showed that the conformation of BSA was changed in the presence of FSD. Copyright © 2015 John Wiley & Sons, Ltd.     

Synthesis and pharmacological evaluation of novel isoquinoline N-sulphonylhydrazones designed as ROCK inhibitors

In this study, we synthesized a new congener series of N-sulphonylhydrazones designed as candidate ROCK inhibitors using the molecular hybridization of the clinically approved drug fasudil (1) and the IKK-β inhibitor LASSBio-1524 (2). Among the synthesized compounds, the N-methylated derivative 11 (LASSBio-2065) showed the best inhibitory profile for both ROCK isoforms, with IC₅₀ values of 3.1 and 3.8?µM for ROCK1 and ROCK2, respectively. Moreover, these compounds were also active in the scratch assay performed in human breast cancer MDA-MB 231 cells and did not display toxicity in MTT and LDH assays. Molecular modelling studies provided insights into the possible binding modes of these N-sulphonylhydrazones, which present a new molecular architecture capable of being optimized and developed as therapeutically useful ROCK inhibitors.     

Notch信号在盐酸法舒地尔诱导大鼠骨髓间充质干细胞向神经元分化过程中的作用

目的:探讨Notch信号通路在盐酸法舒地尔诱导大鼠骨髓间充质干细胞(MSCs)向神经元分化中的作用。方法:实验分为未转染组、转染组(转染Rn-Notch1-siRNA)、阳性对照组(转染Rn-MAPK-1 Control siRNA)及阴性对照组(转染Negative Control siRNA)等4组。采用盐酸法舒地尔诱导大鼠MSCs分化为神经元。倒置荧光显微镜下观察MSCs转染后荧光表达情况;RT-PCR检测Notch1、Hes1和MAPK1 mRNA的表达变化;免疫细胞化学法检测Notch1、神经元烯醇化酶(NSE)、神经微丝蛋白亚单位(NF-M)和胶质纤维酸性蛋白(GFAP)的表达变化;MTT方法检测细胞存活率。结果:①siRNA转染72h,MSCs荧光表达最强,转染率可达91.3%±4.2%;同时,转染组MSCs的Notch1和Hes1 mRNA转录下降(P0.05);MTT提示转染组细胞存活率也显著减少(P0.05)。②盐酸法舒地尔可以诱导MSCs向神经元分化,其中以转染组诱导效果最佳,NSE、NF-M的表达率显著的高于其它各组(P0.05)。结论:盐酸法舒地尔在诱导大鼠MSCs向神经元分化过程中,可能存在Notch信号通路与RhoA/Rho激酶通路信号的协同作用,共同促进MSCs向神经元分化。     

Effects of HA-1077 and Y-27632, two rho-kinase inhibitors, in the human umbilical artery

A role for the small G protein rho and rho-kinase has been shown in smooth muscle contraction regarding Ca⁺⁺ sensitivity. However, there are no data in the literature assessing how this system operates in human umbilical arteries (HUA). Therefore, we evaluated the effects of HA-1077 and Y-27632, two rho-kinase inhibitors, on agonist-(5-hydroxytryptamine [5-HT]) and depolarization-induced (KCl) contractions of HUA. HA-1077 and Y-27632 inhibited 5-HT-induced contractile responses at 10⁻⁴ M concentration but not at 10⁻⁵ M. HA-1077 at 10⁻⁴ M also significantly attenuated contractions induced by 20 mM KCl. In addition, HUA precontracted with 5-HT relaxed concentration dependently in response to HA-1077 and Y-27632. When precontracted with KCl, HUA also relaxed dose-dependently in response to HA-1077, but the maximal relaxation was significantly smaller than the response obtained when precontracted with 5-HT. To determine possible involvement of rho-kinase on agonist-induced intracellular calcium-mediated contractions, tissues were precontracted with 5-HT in Ca⁺⁺-free Krebs solution before cumulative addition of HA-1077 or Y-27632 (10⁻⁷ to 10⁻⁴ M). Both rho-kinase inhibitors relaxed HUA completely. Maximum relaxations of HUA to HA-1077 and Y-27632 were significantly larger than the responses seen in normal Krebs solution and were obtained with lower concentrations of the drugs considered to be more specific for rho-kinase inhibition. However, preincubation of HUA with HA-1077 or Y-27632 (10⁻⁵ M for both) did not affect the 5-HT-induced contractions in this medium. Finally, immunoblot experiments revealed the expression of rho-kinase isoform rockII protein in HUA. These results indicate that rhoA/rho-kinase pathway can contribute to agonist-induced contractions of HUA. However, this effect appears to be limited to intracellular calcium-induced contractions and may be more important in sustaining contractions rather than the initial phase of force development.     

心肌肥厚大鼠心肌Cx43的表达及法舒地尔的干预作用

目的：研究腹主动脉缩窄大鼠心肌缝隙连接蛋白Cx43的变化及法舒地尔的干预作用。方法：腹主动脉缩窄建立心肌肥厚大鼠模型,随机分假手术组,腹主动脉缩窄组、腹主动脉缩窄＋10mg／kg法舒地尔（ip,每天1次,8周）组、腹主动脉缩窄＋40mg／kg（ip,每天1次,8周）。病理切片观察心肌组织学变化;免疫组化法检测心肌Cx43蛋白表达。结果：模型组大鼠心肌细胞排列紊乱,肥大,间隙增宽,Cx43蛋白表达量明显低于正常组;Fas治疗后,死亡率下降,cx43蛋白表达量高于模型组,差异具有统计学意义（P〈0．01）。结论：Fas可能通过调高Cx43蛋白表达,治疗大鼠心肌肥厚。     

LIMK1 depletion enhances fasudil-dependent inhibition of urethral fibroblast proliferation and migration

LIM kinase 1 (LIMK1) is an important regulator of the cell cytoskeleton. This study aimed to examine the role of LIMK1 in mediating the effects of the Rho kinase (ROCK) inhibitor fasudil. In vitro cultures of urethral fibroblasts were divided into LIMK1 knockdown (LIMK1 KD) and LIMK1 control (LIMK1 NC) experimental groups. Each group was incubated with fasudil (50 μmol/L) with or without transforming growth factor β1 (10 ng/mL) for 24 hours. Wound healing and Transwell assays were performed to determine cell migration. Flow cytometry was used to determine apoptosis. LIMK1, collagen I, collagen III, phospho-myosin light chain (p-MLC), alpha smooth muscle actin (α-SMA), and phospho-Cofilin (p-Cofilin) expression was examined by Western blot analysis. The expression of LIMK1 was further validated in human urethral scar tissues. Transwell and wound healing assays revealed that the cells of the LIMK1 KD group exhibited significantly attenuated migration, when compared with those of the LIMK1 NC group ( P < 0.05). Cell migration was also attenuated in the LIMK1 KD group treated with fasudil ( P < 0.05). Flow cytometry analysis revealed that apoptosis was higher in the LIMK1 KD group than that in LIMK1 NC group ( P < 0.05). Apoptosis was also enhanced in the LIMK1 KD group treated with fasudil ( P < 0.05). Western blot analysis demonstrated that LIMK1, collagen I, collagen III, p-MLC, α-SMA, and p-Cofilin expression was significantly attenuated in both the fasudil-treated and untreated LIMK1 KD groups ( P < 0.05). LIMK1 was positively expressed in human urethral scar tissues while it was negatively expressed in normal urethra tissues. In conclusion, loss of LIMK1 expression inhibits the Rho/ROCK pathway-dependent proliferation and migration via downregulation of collagen I, collagen III, p-Cofilin, and α-SMA. LIMK1 loss can also enhance the inhibitory effects of fasudil on the proliferation and migration of urethral fibroblasts.     

法舒地尔对异丙肾上腺素诱导大鼠心肌肥厚的干预作用及其机制

目的：研究法舒地尔对异丙肾上腺素诱导大鼠心肌肥厚的影响及其机制。方法：除正常对照组外,其它SD大鼠均皮下注射异丙肾上腺素（Iso,5 mg/kg）建立心肌肥厚模型。大鼠随机分为4组：正常对照组、Iso模型组、法舒地尔低剂量组（Fas,5 mg/kg,i.p）和法舒地尔高剂量组（Fas,20 mg/kg,i.p）,连续给药8周。给药结束后,血流动力学检测大鼠心率（HR）、左心室收缩压（LVSP）、左心室末舒张压（LVEDP）和左室压力变化最大速率（±dp/dt_max）;分别测定大鼠体重（BW）,心脏重量（HW）,并计算HW/BW;大鼠心肌HE、Masson染色观察组织病理学改变;免疫组化法观察大鼠心肌组织ERK1、ERK2蛋白表达,RT-PCR观察ERK1、ERK2 mRNA的表达。结果：Iso模型组HR和LVEDP明显升高,LVSP和±dp/dt_max明显下降;HW/BW增大;心肌细胞体积变大,排列紊乱,胶原纤维增生;左心室组织ERK1、ERK2蛋白与mRNA表达上调。法舒地尔不同剂量干预后,心脏收缩和舒张能力得到改善,心指数明显下降,心肌细胞体积变小,纤维化减少,ERK1/2 mRNA表达下调,心肌组织损害均得到不同程度改善。结论：ERK1/2信号通路活化参与了异丙肾上腺素诱导的心肌肥厚,法舒地尔对异丙肾上腺素诱导的心肌肥厚具有明显改善作用,这可能与法舒地尔阻断ERK1、ERK2通路活化有关。     

Lack of the presynaptic RhoGAP protein oligophrenin1 leads to cognitive disabilities through dysregulation of the cAMP/PKA signalling pathway

Loss-of-function mutations in the gene encoding for the RhoGAP protein of oligophrenin-1 (OPHN1) lead to cognitive disabilities (CDs) in humans, yet the underlying mechanisms are not known. Here, we show that in mice constitutive lack of Ophn1 is associated with dysregulation of the cyclic adenosine monophosphate/phosphate kinase A (cAMP/PKA) signalling pathway in a brain-area-specific manner. Consistent with a key role of cAMP/PKA signalling in regulating presynaptic function and plasticity, we found that PKA-dependent presynaptic plasticity was completely abolished in affected brain regions, including hippocampus and amygdala. At the behavioural level, lack of OPHN1 resulted in hippocampus- and amygdala-related learning disabilities which could be fully rescued by the ROCK/PKA kinase inhibitor fasudil. Together, our data identify OPHN1 as a key regulator of presynaptic function and suggest that, in addition to reported postsynaptic deficits, loss of presynaptic plasticity contributes to the pathophysiology of CDs.