Down-regulation of microRNA-27b promotes retinal pigment epithelial cell proliferation and migration by targeting Nox2

Aberrant proliferation and migration of retinal pigment epithelium (RPE) cells contributes to the pathology of various ocular diseases. miR-27b has been reported to be crucial in the regulation of cell differentiation, proliferation, apoptosis, and migration. However, the role of miR-27b on RPE proliferation and migration remains largely unknown. Here the effect of miR-27b on ARPE-19 cells under platelet-derived growth factor (PDGF)-BB stimulation was explored. In this study, we found that the expression level of miR-27b was significantly reduced in ARPE-19 cells under PDGF-BB stimulation. Ectopic expression of miR-27b remarkably inhibited PDGF-BB-induced proliferation and migration in ARPE-19 cells. Furthermore, bioinformatic analysis and luciferase reporter assay showed that NADPH oxidase 2 (Nox2) was a direct target for miR-27b, and that knockdown of Nox2 expression mimicked the inhibitory effect of miR-27b on PDGF-BB ?induced proliferation and migration in ARPE-19 cells, whereas, restoration of Nox2 expression showed an opposite effect. In addition, the ROS production and the activation of P13K/AKT/mTOR signaling induced by PDGF-BB were also suppressed by miR-27b overexpression or Nox2 silencing. Thus, these findings indicated that miR-27b exerted its protective role in RPE cells under PDGF-BB stimulation was partially through regulation of Nox2 and its downstream P13K/AKT/mTOR signaling, which might be a potential therapeutic approach for treatment of diseases caused by RPE proliferation, and migration.     

STAT3介导了血小板源性生长因子BB诱导的大鼠血管平滑肌细胞Pim-1表达

 目的： 观察血小板源性生长因子BB(PDGF-BB)是否可以诱导大鼠血管平滑肌细胞（VSMCs）表达Pim-1及Pim-1对VSMCs增殖的影响,探讨STAT3信号分子在这一过程中的作用,为血管重建性疾病（VRD）的研究提供实验依据。方法： 不同浓度PDGF-BB作用不同时间刺激体外培养的VSMCs,用细胞计数法检测增殖;用real-time RT-PCR 检测Pim-1 mRNA表达水平;Western blotting 检测STAT3 的活性变化;用放线菌素D（actinomycin D）、AG490（JAK特异性抑制剂）及siRNA沉默Pim-1和STAT3进行干预。结果： PDGF-BB（20 μg/L）作用VSMCs 24 h,可以诱导细胞增殖,Pim-1沉默抑制了这一过程;正常未经处理的VSMCs Pim-1 mRNA表达量较低,不同浓度PDGF-BB（10 μg/L~50 μg/L ）作用VSMCs 1 h,Pim-1 mRNA表达明显增加,其中以20 μg/L最显著;用PDGF-BB（20 μg/L）作用VSMCs 不同时间（0.5 h~4 h）,可显著上调Pim-1 mRNA表达,以0.5 h最显著。用actinomycin D及AG490预处理后Pim-1 mRNA表达随之降低。PDGF-BB可激活VSMCs中磷酸化STAT3水平,AG490和转染STAT3-siRNA可抑制 STAT3的磷酸化以及相应的Pim-1 mRNA表达。结论： PDGF-BB可通过Pim-1调节VSMCs增殖;STAT3可能参与了PDGF-BB诱导的VSMCs Pim-1表达。     

PDGF-BB 在乳腺浸润性导管癌中的表达及其临床意义

目的:探讨PDGF-BB在乳腺浸润性导管癌中的表达及其与临床病理特征之间的关系。方法:收集2015年6月至2017年8月新疆医科大学第一附属医院经病理证实的乳腺浸润性导管癌80例,采用免疫组化方法检测癌组织及癌旁组织PDGF-BB表达状况,并分析其与临床病理特征关系。结果:乳腺浸润性导管癌组织中PDGF-BB表达明显高于癌旁组织（57.50% vs 13.75%,P<0.05）;PDGF-BB表达与淋巴结转移（P<0.05）和较高的pTNM分期有关（P<0.05）;而与年龄、月经状态、肿瘤直径、PR、ER、HER-2、有无术后复发转移等临床病理特征无关（P>0.05）。结论:PDGF-BB在乳腺浸润性导管癌的发生及进展中起重要作用,其预后价值仍需进一步评价。     

Platelet-rich plasma with keratinocytes and fibroblasts enhance healing of full-thickness wounds

Advances in tissue engineering led to the development of various tissue-engineered skin substitutes (TESS) for the treatment of skin injuries. The majority of the autologous TESS required lengthy and costly cell expansion process to fabricate. In this study, we determine the possibility of using a low density of human skin cells suspended in platelet-rich plasma (PRP)-enriched medium to promote the healing of full-thickness skin wounds. To achieve this, full-thickness wounds of size 1.767 cm² were created at the dorsum part of nude mice and treated with keratinocytes (2 × 10⁴ cells/cm²) and fibroblasts (3 × 10⁴ cells/cm²) suspended in 10% PRP-enriched medium. Wound examination was conducted weekly and the animals were euthanized after 2 weeks. Gross examination showed that re-epithelialization was fastest in the PRP+cells group at both day 7 and 14, followed by the PRP group and NT group receiving no treatment. Only the PRP+cells group achieved complete wound closure by 2 weeks. Epidermal layer was presence in the central region of the wound of the PRP+cells and PRP groups but absence in the NT group. Comparison between the PRP+cells and PRP groups showed that the PRP+cells-treated wound was more mature as indicated by the presence of thinner epidermis with single cell layer thick basal keratinocytes and less cellular dermis. In summary, the combination of low cell density and diluted PRP creates a synergistic effect which expedites the healing of full-thickness wounds. This combination has the potential to be developed as a rapid wound therapy via the direct application of freshly harvested skin cells in diluted PRP.     

瓜蒌薤白汤对平阳霉素所致大鼠肺纤维化肺组织中细胞因子PDGF-BB表达的影响

目的：探讨瓜蒌薤白汤防治肺纤维化的作用机制。方法：大鼠随机分为正常组，模型组，瓜蒌薤白汤组，阳性药氢化可的松组。用平阳霉素（3mg&#183;kg^-1）复制大鼠肺纤维化模型后，用药组每天灌胃瓜蒌薤白汤0．02mL&#183;kg^-1，氢化可的松组腹腔注射5mg&#183;kg^-1。用药28d后处死，观察、比较各组大鼠肺组织中血小板源生长因子BB（PDGF-BB）的表达。结果：模型组大鼠肺组织中PDGF-BB表达均明显高于正常组及用药组（P〈0．05）。结论：瓜蒌薤白汤能明显抑制肺组织中PDGF-BB过度表达。     

The effect of local delivery of PDGF-BB on attachment of human periodontal ligament fibroblasts to periodontitis-affected root surfaces--in vitro

BACKGROUND/AIMS: The purpose of this study was to determine at what concentration does platelet-derived growth factor-BB (PDGF-BB) provide for optimal stimulation of human periodontal ligament fibroblasts (PDL) to adhere to periodontitis affected root surfaces. METHOD: 80 root dentine specimens were prepared from extracted periodontally diseased teeth obtained from patients ranging in age between 35 to 60 years. The root dentine specimens were associated with the subgingival area opposing the periodontal pocket for each extracted tooth. 10 healthy root dentine specimens were obtained from teeth extracted for orthodontic reasons and served as controls. The specimens were distributed into 9 groups (10 specimens in each). In group 1, PDL fibroblasts were cultured on the specimen surface of a diseased treated control. In group 2, PDL fibroblasts were cultured on the specimen surface of a healthy control. In groups 3 to 9, PDL fibroblasts were cultured on a pre-treated specimen surface with concentrations ranging from 5, 10, 20, 50, 100, 200 and 300 ng/ml PDGF-BB, respectively. After 24 h incubation, the media were removed, specimens were fixed, processed for SEM viewing and photographed at 750x. Fibroblast adherence was measured by counting number of cells within a standard test area and cell morphology was scored. RESULTS: Findings suggest dentine specimens pretreated with 5, 10 and 20 ng/ml PDGF-BB were not significantly different in number of adherent cells from the diseased treated control. However, at concentrations of 50, 100, 200 and 300 ng/ml, a highly significant increase in number of adherent fibroblasts was detected when compared to the diseased treated control. At these concentrations, the cell morphology was comparable to that of the healthy control. CONCLUSIONS: PDGF-BB in concentrations equal to or greater than 50 ng/ml demonstrates a significant stimulation of PDL cells adherence to periodontal diseased root surfaces. Since the higher concentrations resulted in similar effects as obtained by 50 ng/ml, it may therefore be considered that this concentration provides for optimal stimulation of human periodontal ligament fibroblasts (PDL) to adhere to periodontitis-affected root surfaces.     

KR 31372, a benzopyran derivative, inhibits oxidized LDL-stimulated proliferation and migration of vascular smooth muscle cells

KR 31372 is a benzopyran derivative. Both [3H]thymidine incorporation and migrations (chemotactic and wound-edge) of cultured smooth muscle cells (SMCs) were greatly stimulated by oxidized low-density lipoprotein (LDL). These effects were significantly suppressed by KR 31372 (10(7) - 10(6) M) and PDGF-BB antibody (10(8) - 10(6) M). Preincubation with KR 31372 led to a decrease in the synthesis of PDGF-BB-like immunoreactivity (PDGF-BB-LI) that had been stimulated by oxidized LDL. Otherwise, KR 31372 and probucol strongly inhibited the production of thiobarbituric acid reactive substances (TBARS) caused by the incubation of LDL with Cu2+ ion, and significantly reduced the intracellular oxidative stress when stimulated with H,O2. Taken together, it is suggested that KR 31372 may inhibit the oxidized LDL-stimulated syntheses of DNA and PDGF-BB, and migration of the SMCs, in part, via the antioxidant activity.     

Enhanced carbon tetrachloride-induced liver fibrosis in mice lacking adiponectin

BACKGROUND & AIMS: Obesity is one of the risk factors for liver fibrosis, in which plasma adiponectin, an adipocytokine, levels are decreased. Hepatic stellate cells play central roles in liver fibrosis. When they are activated, they undergo transformation to myofibroblast-like cells. Adiponectin suppresses the proliferation and migration of vascular smooth muscle cells, whose characteristics are similar to those of hepatic stellate cells. Adiponectin could have biological significances in liver fibrosis. METHODS: The role of adiponectin on liver fibrosis induced by the administration of carbon tetrachloride twice a week for 12 weeks was tested by using adiponectin-knockout mice and an adenovirus-mediated adiponectin-expression system. We also investigated the effect of adiponectin in activated hepatic stellate cells. RESULTS: When mice were administered carbon tetrachloride (300 microL/kg body weight) twice a week for 12 weeks, knockout mice showed extensive liver fibrosis with an enhanced expression of transforming growth factor-beta 1 and connective tissue growth factor compared with wild-type mice (P < 0.05). Injection of adenovirus producing adiponectin (AdADN) before carbon tetrachloride (1000 microL/kg body weight) treatment prevented liver fibrosis in wild-type mice (P < 0.001). Injection of AdADN at 6 weeks attenuated liver fibrosis even though carbon tetrachloride was given for an additional 6 weeks (total of 12 weeks). In cultured hepatic stellate cells, adiponectin suppressed platelet-derived growth factor-induced proliferation and migration and attenuated the effect of transforming growth factor-beta 1 on the gene expression of transforming growth factor-beta 1 and connective tissue growth factor and on nuclear translocation of Smad2. CONCLUSIONS: The findings indicate that adiponectin attenuates liver fibrosis and could be a novel approach in its prevention.     

生长因子(EGF和PDGF-BB)对小鼠骨髓基质干细胞增殖的作用及其意义

目的探讨表皮生长因子(epidermal growth factor,EGF)和血小板源生长因子(platet-derived growth factor,PDGF-BB)对体外培养的小鼠骨髓基质干细胞(murine bone marrow stromal stem cells,mMSCs)增殖的作用,探索小鼠骨髓基质干细胞体外快速增殖的条件和方法.方法将小鼠骨髓基质干细胞进行分离和纯化培养后,加入EGF和PDGF-BB,利用3H胸腺嘧啶核苷(3H-TdR)掺入反映细胞增殖效果,倒置显微镜下观察细胞增殖及分化状态.结果EGF和PDGF-BB干预后,3H-TdR掺入(11456.14±968.86)dpm较对照组(3271.88±420.91)dpm明显增高,说明EGF和PDGF-BB可促进小鼠骨髓基质干细胞的增殖;倒置显微镜下观察可见EGF和PDGF-BB处理组mMSCs具有增殖优势,分化相对延迟,而对照组提前显示出自然分化现象.结论生长因子(EGF和PDGF-BB)可促进小鼠骨髓基质干细胞的增殖,是小鼠骨髓基质干细胞体外大量培养和快速增殖的有效刺激因子.