Prolonged propagation of rat neural stem cells relies on inhibiting autocrine/paracrine bone morphogenetic protein and platelet derived growth factor signals

Continuous expansion of rat neural stem cell lines has not been achieved due to proliferation arrest and spontaneous differentiation in vitro. In the current study, neural precursor cells derived from the subventricular zone of adult rats spontaneously underwent astroglial and oligodendroglial differentiation after limited propagation. This differentiation was largely induced by autocrine or paracrine bone morphogenetic protein and platelet derived growth factor signals. The results showed that, by inhibiting bone morphogenetic protein and platelet derived growth factor signals, adult rat neural precursor cells could be extensively cultured in vitro as tripotent stem cell lines. In addition to adult rat neural stem cells, we found that bone morphogenetic protein antagonists can promote the proliferation of human neural stem cells. Therefore, the present findings illustrated the role of autocrine or paracrine bone morphogenetic protein and platelet derived growth factor signaling in determining neural stem cell self-renewal and differentiation. By antagonizing both signals, the long-term propagation of rat neural stem cell lines can be achieved.

Pirfenidone suppresses the abnormal activation of human Müller cells after platelet-derived growth factor-BB stimulation

AIM: To determine the effect of pirfenidone on the activated human Müller cells by platelet-derived growth factor-BB(PDGF-BB). METHODS: The primary human Müller cells were separated from retinal tissues and established the pathogenic model by stimulated with PDGF-BB. The Müller cells behaviour of normal group and the model group was measured by MTT assay, Trypan blue assay, cell migration assay, and collagen contraction assay. The expression of transforming growth factor(TGF)-β1,-β2, and pigment epithelium-derived factor(PEDF) was estimated with realtime polymerase chain reaction(PCR), Western blot and immunofluorescence analyses. RESULTS: A pathogenic/proliferative model of Müller cells was established by stimulating normal cultured Müller cells with 10 ng/mL PDGF-BB for 48 h. After treated with 0.2 and 0.3 mg/mL pirfenidone, the proliferation, migration and collagen contraction was statistically significantly depressed in the model group compared with the normal groups. The expression levels of TGF-β1 and TGF-β2 were significantly down-regulated, while the PEDF expression was significantly up-regulated after treated with 0.2 and 0.3 mg/mL pirfenidone in the model group. CONCLUSION: Pirfenidone effectively suppress the proliferation, migration and collagen contraction of the human Müller cells stimulated with PDGF-BB through down-regulation of TGF-β1/TGF-β2 and up-regulation of PEDF.

Effect of recombinant human platelet-derived growth factor B on cat corneal endothelial cell viability mediated by adeno-associated virus

AIM: To transduce recombinant human platelet-derived growth factor B (PDGF-B) gene adeno-associated virus(AAV) to in vitro cultured cat corneal endothelial cell (CEC) and observe the effect of the expressed PDGF-BB protein on the viability of cat CEC. METHODS: Cat cornea endothelium was torn under microscope and rapidly cultivated in DMEM to form single layer CEC and the passage 2 endothelial cells were used in this study. The recombinant human PDGF-B gene AAV was constructed and transduced into cat CEC directly. Three groups were as following: blank control group, AAV control group and recombinant AAV group. At 24 hours, 48 hours, and 5 days after transduction, total RNA was extracted from the CEC by Trizol and the expression of PDGF-B gene was detected by fluorescence quantitative polymerase chain reaction. Viability of the transduced CEC was detected at 48 hours after transduction by MTT assay. Cell morphology was observed under inverted phase contrast microscope. RESULTS: With the torn endothelium culture technique, we rapidly got single layer cat CEC. At 24 hours, 48 hours and 5 days after transduction, fluorescence quantitative polymerase chain reaction showed there was no significant difference of the expressed PDGF-B gene mRNA between blank control group and AAV control group (P>0.05). In contrast, there were significant differences between two control groups and recombinant AAV group (P<0.05). MTT assay showed that in recombinant AAV group, the expressed PDGF-BB protein could promote the viability of cat CEC. Morphology observation showed at 48 hours after transduction, cells in CEC-AAV-PDGF-B group proliferated into bigger scales in regular triangle to hexagon shape with distinct boundary, while the number of cells was significantly less in the two control groups. CONCLUSION: The recombinant AAV-PDGF-B expresses biological active PDGF-BB protein in cat CEC, which promotes the viability and proliferation of cells.

Vascular endothelial growth factor/platelet-derived growth factor receptor pathway is involved in bone marrow mesenchymal stem cell differentiation and directional migration toward gliomas

BACKGROUND： Vascular endothelial growth factor （VEGF） induces bone marrow-derived mesenchymal stem cell （BMSC） differentiation into vascular endothelial-like cells and promotes BMSC migration toward gliomas. However, the molecular mechanisms by which VEGF induces BMSC differentiation and migration remain poorly understood. OBJECTIVE; To investigate the role of platelet-derived growth factor （PDGF） receptor （PDGFR） in BMSC differentiation and migration induced by VEGE DESIGN, TIME AND SETTING： A parallel, controlled, in vitro experiment was performed at the Molecular Neurobiology ＆ Neural Regeneration and Repairing Laboratory, Anhui Provincial Hospital of Anhui Medical University, China from June 2008 to March 2009. MATERIALS： U87 glioma cells were purchased from Shanghai Institutes for Biological Sciences; mouse anti-human PDGFR and VEGF receptor （VEGFR） monoclonal antibodies were purchased from Peprotech, USA. METHODS： Isolated BMSCs were precultured with neutralizing antibody for VEGFR-1, VEGFR-2, PDGFR-α, and PDGFR-β to block biological activity of related receptors, followed by induced differentiation with 50μg/L VEGF. BMSCs induced with 50μg/L VEGF alone served as the VEGF-induced group. The control group remained untreated. MAIN OUTCOME MEASURES： Cell surface markers were identified by flow cytometry; BMSC surface cytokine receptor expression was detected by reverse transcription-polymerase chain reaction; the Transwell model was used to observe cell migration. RESULTS： After blocking the PDGFR, VEGF did not induce BMSC cell surface marker CD-31 or von Willebrand factor （vWF） expression. However, inhibition with VEGF receptor blocking agents, VEGF induced BMSCs to express CD-31 and vWE Following inhibition of the PDGFR, the number of cells migrating through the polycarbonate membrane Transwell chamber was decreased, as well as the number of BMSCs migrating to glioma cells. However, through the use of VEGF receptor blocking agents, the number of migrating cells remained unchanged. VEGF preculture increased the number of BMSCs migrating to gliomas. CONCLUSION： VEGF interacts with PDGFRs on the BMSC surface to attract BMSC directional migration and induce BMSC differentiation. The VEGF/PDGFR pathway participates in BMSC directional migration to glioma. VEGF pretreatment increased efficiency of BMSC migration to glioma.

Distribution of platelet-derived growth factor-alpha receptor expressing oligodendrocyte precursor cells in the adult rat brain

BACKGROUND： Studies have demonstrated that NG2-positive glial cells in the adult rats are predominantly located in the gray and white matter of the cerebral cortex and hippocampus. Platelet-derived growth factor-a receptor （PDGF-αR） cells are a subset of oligodendrocytes, which are not as mature as NG2-positive cells. Distribution and migration of PDGF-αR-positive cells in the rat brain remain poorly understood. OBJECTIVE： Using immunohistochemical methods, the distribution of oligodendrocyte precursor cells （PDGF-αR-positive） was analyzed in the adult rat brain. DESIGN, TIME AND SETTING： Immunohistochemical study was performed at the Department of Histology and Embryology of the Third Military Medical University from September 2007 to September 2008. MATERIALS： Rabbit anti-PDGF-αR polyclonal antibody was purchased from Santa Cruz Biotechnology, USA. Streptomycin-avidin-biotin complex immunohistochemistry kit was purchased from Zhongshan Goldenbridge Biotechnology, China. METHODS： Whole brains from 5 healthy, adult, Wistar rats were collected for immunohistochemistry, and the mean value of PDGF-αR-expressing cells was quantified. The absolute values were translated to ranked data of high, moderate, and low grades （high grade： 10 positive cells; moderate grade： 5-9 cells; low grade： 〈 5 cells in a 400 × visual field）. Based on the number of cell processes and branches, as well as the number of PDGF-αR-positive cells, in different regions, the cells were classified into three categories, i.e., type Ⅰ-Ⅲ. From type I to type Ill, the number of processes gradually increased. MAIN OUTCOME MEARSURES： The number and distribution of PDGF-αR-positive cells in different brain regions of adult rats. RESULTS： PDGF-αR-positive cells were located in the forebrain and midbrain, but not in the cerebellum or brainstem. In the olfactory bulb and hippocampus, a total of 60% PDGF-αR-positive cells were type Ⅰ and these cells were not mature as others. In the cerebral cortex, olfactory system, hippocampus, and optic chiasma, where neuronal bodies aggregated, approximately 40% of the PDGF-αR-positive cells were type Ⅱ, with few type Ⅲ cells. In the white matter, corpus callosum, basal nucleus, and thalamus, PDGF-αR-positive cell density was moderate. In the olfactory bulb and hippocampus, PDGF-αR-positive cell density was high. PDGF-αR-positive cells were not observed in the cerebellum or brainstem CONCLUSION： PDGF-αR-positive cells were aggregated in the olfactory bulb and hippocampus in the adult, rat brain, but few cells were detected in the cerebellum and brainstem.

Effects of interleukin-1α on platelet-derived growth factor release from bovine cerebral microvascular endothelial cells

The present study showed that, interleukin-1α (IL-1α) stimulateal cultured bovine cerebral microvascular endothelial cells (BCMEC) releasing growth factor which promoted bovine cerebral microvascular smooth muscle cells (BCMSMC) proliferation in a dose-dependent manner. The mitogenic activity in conditioned medium of BCMEC stimulated by IL-1α was neutralized significantly by the antibody to platelet-derived growth factor (PDGF). Imperatorin (Imp), iso-Imperatorin (iso Imp) and 6-(α,α-phenylacetylpiperazinyl)phenyl-5-methyl-4,5-dihydro-3 (2H)-pyridazinone (PMDP) did not affect the releasing of PDGF from IL-1α stimulated BCMEC, but inhibited the promotion of PDGF on the proliferation of BCMSMC. We concluded that the promotion of IL-1α on the proliferation of BCMSMC should be mediated by some growth factors, such as PDGF.

Integrin binding peptides facilitate growth and interconnected vascular-like network formation of rat primary cortical vascular endothelial cells in vitro

Neovascularization and angiogenesis in the brain are important physiological processes for normal brain development and repair/regeneration following insults. Integrins are cell surface adhesion receptors mediating important function of cells such as survival, growth and development during tissue organization, differentiation and organogenesis. In this study, we used an integrin-binding array platform to identify the important types of integrins and their binding peptides that facilitate adhesion, growth, development, and vascular-like network formation of rat primary brain microvascular endothelial cells. Brain microvascular endothelial cells were isolated from rat brain on post-natal day 7. Cells were cultured in a custom-designed integrin array system containing short synthetic peptides binding to 16 types of integrins commonly expressed on cells in vertebrates. After 7 days of culture, the brain microvascular endothelial cells were processed for immunostaining with markers for endothelial cells including von Willibrand factor and platelet endothelial cell adhesion molecule. 5-Bromo-2′-dexoyuridine was added to the culture at 48 hours prior to fixation to assess cell proliferation. Among 16 integrins tested, we found that α5β1, αvβ5 and αvβ8 greatly promoted proliferation of endothelial cells in culture. To investigate the effect of integrin-binding peptides in promoting neovascularization and angiogenesis, the binding peptides to the above three types of integrins were immobilized to our custom-designed hydrogel in three-dimensional(3 D) culture of brain microvascular endothelial cells with the addition of vascular endothelial growth factor. Following a 7-day 3 D culture, the culture was fixed and processed for double labeling of phalloidin with von Willibrand factor or platelet endothelial cell adhesion molecule and assessed under confocal microscopy. In the 3 D culture in hydrogels conjugated with the integrin-binding peptide, brain microvascular endothelial cells formed interconnected vascular-like network with clearly discernable lumens, which is reminiscent of brain microvascular network in vivo. With the novel integrin-binding array system, we identified the specific types of integrins on brain microvascular endothelial cells that mediate cell adhesion and growth followed by functionalizing a 3 D hydrogel culture system using the binding peptides that specifically bind to the identified integrins, leading to robust growth and lumenized microvascular-like network formation of brain microvascular endothelial cells in 3 D culture. This technology can be used for in vitro and in vivo vascularization of transplants or brain lesions to promote brain tissue regeneration following neurological insults.

Expression of NG2 and platelet-derived growth factor receptor alpha in the developing neonatal rat brain

Platelet-derived growth factor receptor alpha （PDGFRct） is a marker of oligodendrocyte precursor cells in the central nervous system. NG2 is also considered a marker of oligodendrocyte precursor cells. However, whether there are differences in the distribution and morphol- ogy of oligodendrocyte precursor cells labeled by NG2 or PDGFRa in the developing neonatal rat brain remains unclear. In this study, by immunohistochemical staining, NG2 positive （NG2＋） cells were ubiquitous in the molecular layer, external pyramidal layer, internal pyramidal layer, and polymorphic layer of the cerebral cortex, and corpus callosum, external capsule, piriform cortex, and medial septal nucleus. NG2~ cells were stellate or fusiform in shape with long processes that were progressively decreased and shortened over the course of brain development. The distribution and morphology of PDGFRct positive （PDGFRa＋） cells were coincident with NG2＋ cells. The co- localization of NG2 and PDGFRu in the cell bodies and processes of some cells was confirmed by double immunofluorescence labeling. Moreover, cells double-labeled for NG2 and PDGFRa were predominantly in the early postnatal stage of development. The numbers of NG2＋/PDGFRa＋ cells and PDGFRa＋ cells decreased, but the number of NG2＋ cells increased from postnatal days 3 to 14 in the developing brain. In addition, amoeboid microglial cells of the corpus callosum, newborn brain macrophages in the normal developing brain, did not express NG2 or PDGFRu, but NG2 expression was detected in amoeboid microglia after hypoxia. The present results suggest that NG2 and PDGFRct are specific markers of oligodendrocyte precursor cells at different stages during early development. Additionally, the NG2 protein is involved in inflammatory and pathological processes of amoeboid microglial cells.

A partition-type tubular scaffold loaded with PDGF-releasing microspheres for spinal cord repair facilitates the directional migration and growth of cells

The best tissue-engineered spinal cord grafts not only match the structural characteristics of the spinal cord but also allow the seed cells to grow and function in situ.Platelet-derived growth factor（PDGF） has been shown to promote the migration of bone marrow stromal cells;however,cytokines need to be released at a steady rate to maintain a stable concentration in vivo.Therefore,new methods are needed to maintain an optimal concentration of cytokines over an extended period of time to effectively promote seed cell localization,proliferation and differentiation.In the present study,a partition-type tubular scaffold matching the anatomical features of the thoracic 8–10 spinal cord of the rat was fabricated using chitosan and then subsequently loaded with chitosan-encapsulated PDGF-BB microspheres（PDGF-MSs）.The PDGF-MS-containing scaffold was then examined in vitro for sustained-release capacity,biocompatibility,and its effect on neural progenitor cells differentiated in vitro from multilineage-differentiating stress-enduring cells（MUSE-NPCs）.We found that pre-freezing for 2 hours at-20°C significantly increased the yield of partition-type tubular scaffolds,and 30 μL of 25% glutaraldehyde ensured optimal crosslinking of PDGF-MSs.The resulting PDGF-MSs cumulatively released 52% of the PDGF-BB at 4 weeks in vitro without burst release.The PDGF-MS-containing tubular scaffold showed suitable biocompatibility towards MUSE-NPCs and could promote the directional migration and growth of these cells.These findings indicate that the combination of a partition-type tubular scaffold,PDGF-MSs and MUSENPCs may be a promising model for the fabrication of tissue-engineered spinal cord grafts.

Basic fibroblast growth factor gene transfection in repair of internal carotid artery aneurysm wall

Surgery or interventional therapy has some risks in the treatment of cerebral aneurysm. We established an internal carotid artery aneurysm model by dripping elastase in the crotch of the right internal and external carotid arteries of New Zealand rabbits. Following model induction, lentivirus carrying basic fibroblast growth factor was injected through the ear vein. We found that the longer the action time of the lentivirus, the smaller the aneurysm volume. Moreover, platelet-derived growth factor expression in the aneurysm increased, but smooth muscle 22 alpha and hypertension-related gene 1 mRNA expression decreased. At 1,2, 3, and 4 weeks following model establishment, following 1 week of injection of lentivirus carrying basic fibroblast growth factor, the later the intervention time, the more severe the blood vessel damage, and the bigger the aneurysm volume, the lower the smooth muscle 22 aJpha and hypertension-related gene ~ mRNA expression. Simultaneously, platelet-derived growth factor expression decreased. These data suggest that recombinant lentivirus carrying basic fibroblast growth factor can repair damaged cells in the aneurysmal wall and inhibit aneurysm dynamic growth, and that the effect is dependent on therapeutic duration.

人尿源性干细胞的分离培养及诱导分化为平滑肌细胞

背景:传统尿路修复重建手段受限于供体短缺、并发症多以及生理功能恢复不理想等问题,组织工程策略为此领域提供了新方向。鉴于尿路主要由肌性组织构成,其中关键在于发掘适合的种子细胞并高效诱导分化为平滑肌细胞,但关于不同平滑肌细胞诱导方案效能的对比研究仍较为匮乏。目的:旨在分离、培养及鉴定人尿源性干细胞,并比较两种不同成平滑肌诱导方案的效果。方法:采用多次离心法从11份健康成人志愿者尿液中分离提取尿源性干细胞,使用流式细胞仪进行表面标志物的鉴定,通过成骨、成脂诱导分化来验证尿源性干细胞的多向分化潜能。尿源性干细胞分别在含转化生长因子β1以及转化生长因子β1联合血小板衍生生长因子的成平滑肌细胞诱导分化培养基中诱导分化14 d,采用免疫荧光染色和Western blot检测平滑肌特异性蛋白(α-SMA、SM22)的表达差异。结果与结论:①成功从8份健康人尿液中分离出尿源性干细胞,细胞呈“米粒”样,具有很好的分裂增殖能力;②尿源性干细胞高表达间充质干细胞表面标志物CD73、CD90和CD44,极低表达造血干细胞表面标志物CD34和CD45,不表达CD19、CD105和HLA-DR;③经成骨和成脂诱导分化后,可见明显的钙结节和脂滴形成,茜素红染色和油红O染色结果呈阳性;④成平滑肌诱导培养14 d,免疫荧光染色显示转化生长因子β1/血小板衍生生长因子组尿源性干细胞成平滑肌诱导分化率显著高于转化生长因子β1组(P<0.005);⑤成平滑肌诱导培养14 d,Western blot检测显示转化生长因子β1/血小板衍生生长因子组α-SMA和SM22蛋白表达量显著高于转化生长因子β1组(P<0.005)。结果表明:尿源性干细胞可以通过多次离心法无创分离获取;相较于单纯转化生长因子β1,转化生长因子β1/血小板衍生生长因子联合应用能显著提高尿源性干细胞诱导分化为平滑肌细胞的效率。

PDGFD对人牙髓干细胞迁移及成牙本质向分化的作用

目的:探讨人重组血小板来源的生长因子D(platelet-derived growth factor D,PDGFD)对人牙髓干细胞(human dental pulp stem cells,hDPSCs)迁移及成牙本质向分化的作用。方法:利用酶解法分离培养hDPSCs,流式细胞术鉴定所培养的间充质干细胞表面分子标志物的表达,诱导hDPSCs三系分化并使用相应染色鉴定,以表征其多向分化潜能。应用细胞划痕实验检测PDGFD对hDPSCs迁移能力的影响,利用实时荧光定量PCR及蛋白免疫印迹法检测PDGFD对hDPSCs成牙本质相关mRNA及蛋白表达的影响,利用碱性磷酸酶(alkaline phosphataseI,ALP)和茜素红(alizarin red staining,ARS)染色检测PDGFD对hDPSCs矿化的影响。采用SPSS 26.0软件包对数据进行统计学分析。结果:细胞形态学分析、流式细胞术鉴定和三系分化结果显示,所分离得到的细胞符合hDPSCs特征,并且具有多向分化潜能。细胞划痕实验结果表明,12 h时,仅50 ng/mL的PDGFD对hDPSCs的迁移能力有影响;24 h时,10和50 ng/mL的PDGFD对hDPSCs的迁移能力均有影响。PCR结果显示,10与50 ng/mL的PDGFD均对hDPSCs的成牙本质分化有促进作用,50 ng/mL的PDGFD对hDPSCs的成牙本质分化更为显著。蛋白免疫印迹实验、ALP及ARS染色所得结果和PCR结果相同。结论:成功分离并培养了具有典型间充质干细胞表型和多向分化潜能的hDPSCs。10和50 ng/mL浓度的PDGFD对hDPSCs的迁移和成牙本质向分化均有促进作用,其中50 ng/mL的PDGFD的促进作用更为显著。

血小板衍生生长因子对脉络膜黑色素瘤细胞活性及侵袭能力的影响

目的探讨血小板衍生生长因子(PDGF)对脉络膜黑色素瘤(choroidal melanoma,CM)细胞活性及侵袭能力的影响。方法将CM细胞分为A、B组,分别转染空载体和敲降PDGF的慢病毒,采用RT-qPCR技术检测两组细胞中PDGF mRNA相对表达量,采用XTT实验检测两组细胞活性,采用Transwell实验检测两组细胞侵袭能力,采用Western blot实验检测两组细胞上皮-间质转化(EMT)及基质金属蛋白酶(MMPs)相关标志物蛋白的相对表达量。GEPIA数据库分析PDGF水平与CM患者预后的关系。结果与A组比较,B组细胞中PDGF RNA相对表达量下降(t=176.30,P<0.05),细胞存活数目下降及侵袭能力减弱(F=57.21,t=14.10,P<0.05)。Western blot实验结果显示,与A组相比,B组细胞中E-cadherin相对表达量升高,N-cadherin、Snail、Vimentin、MMP9及MT1 MMP的相对表达量下降(t=4.13~14.14,P<0.05)。GEPIA数据库分析显示,PDGF-A、PDGF-B高表达与CM患者的不良预后有关(P<0.05)。结论PDGF具有增强CM细胞活性,促进CM细胞侵袭的作用,其机制可能与诱导细胞EMT的发生有关。

血清CCL-20、PDGF-BB、CYFRA21-1水平对NSCLC患者靶向治疗效果的预测价值

目的分析血清趋化因子配体20(CCL-20)、血小板源性生长因子BB(PDGF-BB)、细胞角化素蛋白片段19(CYFRA21-1)对非小细胞肺癌(NSCLC)患者靶向治疗效果的预测价值。方法选取进行靶向治疗的79例中晚期NSCLC患者,均持续治疗2月,评价患者近期疗效。收集患者一般临床资料,并于治疗前后分别检测患者血清趋化因子CCL-20、PDGF-BB、CYFRA21-1水平,比较不同疗效患者间相关资料差异,分析影响疗效的因素,并利用ROC分析血清趋化因子CCL-20、PDGF-BB、CYFRA21-1水平预测近期疗效的价值。结果79例中晚期NSCLC患者均完成2个月的靶向治疗,治疗总有效率为45.57%(36/79)。有效组共36例,无效组(SD+PD)共43例,2组年龄、性别、病理类型相较无差异(P>0.05);有效组TNMⅢB期、高分化占比高于无效组(P<0.05);有效组治疗前后血清CCL-20、PDGF-BB、CYFRA21-1水平均低于无效组(P<0.05)。多因素Logistic回归分析结果显示,治疗前血清CCL-20、PDGF-BB、CYFRA21-1水平为影响疗效的独立因素(OR=9.574,10.903,11.156,P<0.05)。ROC分析结果显示,治疗前血清CCL-20、PDGF-BB、CYFRA21-1水平均具有预测临床疗效的价值(AUC=0.775,0.896,0.669,P<0.05)。结论中晚期NSCLC患者血清CCL-20、PDGF-BB、CYFRA21-1水平与靶向治疗效果有关,可作为靶向治疗近期疗效评估的辅助性指标。

薯蓣皂苷对大鼠糖尿病肾病肾小管上皮细胞的影响

目的:探讨薯蓣皂苷对糖尿病肾病大鼠肾小管上皮细胞的影响及机制。方法:建立糖尿病肾病大鼠模型,分成对照组、模型组和薯蓣皂苷低、中、高剂量组,薯蓣皂苷低、中、高剂量组给予不同浓度(20、40、80 mg/kg)薯蓣皂苷灌胃,对照组与模型组给予等量生理盐水。收集正常大鼠肾小管上皮细胞培养,分为空白对照组、高糖组和薯蓣皂苷低、中、高剂量组,薯蓣皂苷低、中、高剂量组给予不同浓度(20、40、80μmol/L)薯蓣皂苷处理。H-E染色观察肾组织病理变化,RT-qPCR检测血小板衍化生长因子-BB(PDGF-BB)mRNA水平,ELISA法检测24 h尿白蛋白水平及肾小管上皮细胞中肿瘤坏死因子-α(TNF-α)、白细胞介素1β(IL-1β)、活性氧(ROS)、丙二醛(MDA)水平,流式细胞术检测细胞凋亡率,免疫印迹检测PDGF-BB蛋白表达。结果:与模型组比较,薯蓣皂苷组尿白蛋白及肾组织PDGF-BB mRNA水平降低,呈剂量依赖,肾组织病理损伤好转;细胞实验中,与高糖组比较,薯蓣皂苷组肾小管上皮细胞中PDGF-BB mRNA及蛋白水平以及TNF-α、IL-1β、MDA、ROS含量和细胞凋亡率降低,呈剂量依赖性。结论:薯蓣皂苷能抑制糖尿病肾病大鼠肾小管上皮细胞炎症反应、过氧化损伤及细胞凋亡,降低PDGF-BB表达,保护肾小管上皮细胞。

PDGFRα^(+)细胞上P2Y1-SK3通路对功能性消化不良大鼠胃肠动力的调控机制

目的探究血小板衍生生长因子受体α^(+)(PDGFRα^(+))细胞上P2Y1-小电导Ca^(2+)激活K^(+)(SK3)通道对功能性消化不良(FD)大鼠胃肠动力的影响。方法将30只SD大鼠随机分为空白组、模型组、P2Y1受体抑制剂(MRS2500)组,每组10只。除空白组外,其余两组采用多因素干预法建立FD大鼠模型。造模成功后抑制剂组予以尾静脉注射P2Y1抑制剂MRS2500,其他组不采取干预措施。处理结束后进行行为学和胃肠动力学检测;用BL-420S生物信号系统采集并分析胃肠生物电信息;取胃窦组织评估病理变化;采用免疫印迹、实时荧光定量PCR技术检测各组大鼠胃窦PDGFRα、C-kit(卡介尔间质细胞特异性指标)、P2Y1和SK3的表达情况;采用免疫荧光法检测胃窦PDGFRα和C-kit、P2Y1、SK3的组织表达和共定位情况;用钙检测试剂盒检测胃窦组织中Ca^(2+)含量变化。结果FD模型建立后,大鼠活动度、体重增长速度和进食量都显著降低,胃肠动力减弱,胃窦内PDGFRα、C-kit、P2Y1和SK3表达水平降低。MRS2500干预后,P2Y1受体抑制剂组大鼠较模型组大鼠体重增长率和进食量升高,胃肠动力减弱情况改善,PDGFRα、P2Y1和SK3表达水平进一步降低,C-kit表达水平升高,Ca^(2+)含量降低。PDGFRα与C-kit在胃窦中不存在共表达,而PDGFRα与P2Y1、SK3共表达。结论长期的饮食和情绪失调会刺激肠神经系统释放抑制性神经递质,这一过程通过PDGFRα^(+)细胞上P2Y1受体引起SK3通道的Ca^(2+)敏感性降低,在多因素刺激诱导的FD模型大鼠胃肠动力障碍中起重要作用。

延胡索乙素改善PDGF-BB诱导的VSMCs氧化应激损伤的机制

目的研究延胡索乙素(Thp)对血小板衍生生长因子-BB(PDGF-BB)诱导的大鼠主动脉血管平滑肌细胞(VSMCs)氧化应激损伤的保护作用,并基于核因子红系2相关因子2(Nrf2)/血红素加氧酶1(HO-1)信号通路探究其可能机制。方法在Thp抑制PDGF-BB诱导的VSMCs氧化应激损伤效应研究中,将VSMCs分为对照组、PDGF-BB组(25 ng/mL)及Thp低、中、高浓度组(5、10、20 mg/mL)。在Thp作用机制研究(沉默Nrf2)中,将VSMCs分为PDGF-BB+阴性对照siRNA(NC-siNrf2)组(25 ng/mL PDGFBB+NC-siNrf2),PDGF-BB+Thp+NC-siNrf2组(25 ng/mL PDGF-BB+10 mg/mL Thp+NC-siNrf2),PDGF-BB+Nrf2小干扰RNA(siNrf2)组(25 ng/mL PDGF-BB+siNrf2),PDGF-BB+Thp+siNrf2组(25 ng/mL PDGF-BB+10.0 mg/mL Thp+siNrf2)。2个实验均检测VSMCs的增殖、迁移能力,活性氧(ROS)水平,超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性以及Nrf2和HO-1蛋白表达。结果与对照组比较,PDGF-BB组VSMCs的增殖、迁移能力显著增强(P<0.01),ROS水平显著升高(P<0.01),SOD、CAT活性及Nrf2、HO-1蛋白的相对表达量均显著降低(P<0.01);与PDGF-BB组比较,Thp不同浓度组VSMCs的增殖、迁移能力均显著下降(P<0.01),ROS水平均显著降低(P<0.01),SOD、CAT活性及Nrf2、HO-1蛋白的相对表达量均显著升高(P<0.01)。沉默Nrf2可显著逆转Thp对PDGF-BB诱导VSMCs氧化应激损伤的改善作用(P<0.01)。结论Thp可以通过激活Nrf2介导的抗氧化防御途径来降低VSMCs的氧化应激水平,从而抑制VSMCs的增殖、迁移。

电针通过PLC/IP3通路改善功能性消化不良大鼠胃肠动力障碍

目的确定电针是否调节了血小板衍生生长因子受体α阳性(PDGFRα+)细胞中磷脂酶C(PLC)/肌醇-1,4,5-三磷酸酯(PLC/IP3)通路,从而改善功能性消化不良(FD)胃肠动力障碍。方法将40只SD大鼠随机分为5组:空白组、模型组、电针组、U73122(PLC抑制剂)组、U73122+电针组,每组8只。除空白组外所有大鼠采用多因素应激干预法建立FD大鼠模型。造模成功后,U73122组予以腹腔注射抑制剂,电针组取足三里和太冲穴,U73122+电针组在针刺前2 h注射抑制剂。10 d后行胃肠动力学检测;采用免疫印迹法检测PDGFRα、PLC、P-PLC、IP3的蛋白表达水平;用免疫荧光检测PDGFRα和PLC、IP3的平均荧光密度和共定位表达情况;电子显微镜观察胃窦区域缝隙连接(GJ)情况。结果造模后大鼠胃肠动力减弱,PDGFRα、PLC和IP3的蛋白表达水平显著降低,GJ增宽,细胞形态改变;与模型组比较,电针组、U73122组和U73122+电针组大鼠胃肠动力显著改善,胃窦PDGFRα、PLC、P-PLC、IP3表达水平上升,GJ稍紧密,细胞形态恢复;U73122组和U73122+电针组胃窦PDGFRα、PLC、P-PLC、IP3表达水平无明显差异;PDGFRα与PLC和IP3存在荧光共定位。结论电针通过激活PDGFRα+细胞中的PLC/IP3通路改善FD大鼠的胃肠动力障碍。

Nrf2、LTBP2、PECAM1与NSCLC患者EGFR靶向治疗反应性关系及意义

目的:探讨血清核因子E2相关因子2(Nrf2)、转化生长因子结合蛋白2(LTBP2)、血小板内皮细胞黏附分子1(PECAM1)与非小细胞肺癌(NSCLC)患者表皮生长因子受体(EGFR)靶向治疗反应性关系及意义。方法:选取我院2021年1月—2023年1月收治的95例NSCLC患者为研究对象,根据EGFR靶向治疗3个月后的治疗反应性分为有效组(54例)、无效组(41例)。比较2组治疗前及治疗1个月、2个月后血清Nrf2、LTBP2、PECAM1水平,分析治疗1个月、2个月后血清Nrf2、LTBP2、PECAM1水平与NSCLC患者EGFR靶向治疗反应性相关性,偏回归分析治疗无效的影响因素,受试者工作特征曲线(ROC)分析治疗1个月、2个月后血清Nrf2、LTBP2、PECAM1水平联合检测对NSCLC患者EGFR靶向治疗效果的预测价值。结果:治疗1个月、2个月后无效组血清Nrf2、LTBP2、PECAM1水平均高于有效组(P<0.05);相关性分析发现,治疗1个月、2个月后血清Nrf2、LTBP2、PECAM1水平与治疗反应性均呈负相关(P<0.05);Logistic回归分析发现,治疗1个月、2个月后血清Nrf2、LTBP2、PECAM1水平为NSCLC患者EGFR靶向治疗效果的影响因素(P<0.05);ROC曲线分析发现,治疗1个月、2个月后血清Nrf2、LTBP2、PECAM1水平联合预测治疗无效的曲线下面积(AUC)分别为0.761、0.816,最佳预测敏感度、特异度分别为(85.37%、66.67%)、(92.68%、70.37%),高于单一指标预测(P<0.05)。结论:血清Nrf2、LTBP2、PECAM1水平与NSCLC患者EGFR靶向治疗反应性密切相关,并在预测治疗效果方面具有较高效能。

乙型肝炎病毒感染者血清白细胞介素17、血小板与淋巴细胞比值、血管内皮细胞生长因子表达意义及与疾病进展的相关性探讨

目的探讨乙型肝炎病毒(hepatitis B virus,HBV)感染者血清白细胞介素17(interleukin 17,IL17)、血小板与淋巴细胞比值(platelet to lymphocyte ratio,PLR)、血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)表达意义及与疾病进展的相关性。方法选择2022年6月至2024年3月昆山市第一人民医院收治的82例HBV感染者为研究组,根据病情进展程度将82例患者分为A组(慢性乙型肝炎)37例、B组(代偿期肝硬化)24例、C组(失代偿期肝硬化)21例,选择同期30例健康体检者为对照组。此外根据血清HBV DNA载量将HBV感染者分为阴性组18例(<1.0×10^(5)copy/ml)、低载量组26例(1.0×10^(5)~1.0×10^(8)copy/ml)和高载量组38例(>1.0×10^(8)copy/ml)。检测所有受试者的血清IL-17、PLR、VEGF表达水平及HBV DNA载量,分析血清IL-17、PLR、VEGF表达水平与疾病进展相关性。结果研究组患者血清IL-17、PLR、VEGF表达水平明显高于对照组(P<0.05),C组患者血清IL-17、PLR、VEGF水平显著高于B组和A组,而B组患者血清IL-17、PLR、VEGF水平显著高于A组;高载量组患者血清IL-17、PLR、VEGF水平显著高于低载量组和阴性组,而低载量组患者血清IL-17、PLR、VEGF水平显著高于阴性组(均P<0.05);Pearson相关系数分析血清IL-17、PLR、VEGF水平升高与HBV DNA载量、代偿期肝硬化、失代偿期肝硬化呈正相关(P<0.05);多因素Logistic回归分析结果显示,IL-17、PLR、VEGF表达水平升高是疾病进展的危险因素(P<0.05)。血清IL-17、PLR、VEGF联合诊断代偿期肝硬化、失代偿期肝硬化的曲线下面积分别为0.823、0.835。结论血清IL-17、PLR和VEGF作为反映HBV感染及疾病进展的重要生物标志物,其水平变化与HBV DNA载量、代偿期肝硬化和失代偿期肝硬化密切相关。通过监测这些细胞因子的水平变化,有助于我们更准确地评估HBV感染者的病情严重程度及预后风险,为临床诊疗提供有价值的参考依据。