人源性干细胞分化的神经细胞在药物神经毒性评价中的应用

人源性干细胞可自我更新,且具有多向分化潜能.人多能干细胞可分化为神经元、胶质细胞和类脑器官等,为寻求药物早期筛选和神经毒性临床前评价的新模型提供了可能.目前基于人源性干细胞分化的神经细胞的体外模型已用于药物筛选、有效性和安全性评价以及阐明未知的疾病发生机制,为开展临床试验奠定了良好的基础,并且有助于减少药物临床应用中不...     

胚胎干细胞及代谢组学在药物安全性研究中的应用进展

胚胎干细胞(ESCs)是来源于胚胎囊胚期内细胞团的一类未分化的全能干细胞,具有无限复制、自我更新和多向分化的生物学特性。ESCs在特定条件下能够被诱导分化成各种特化的器官或组织细胞。这些特定功能的细胞可作为体外实验的模型应用于新药开发早期药物有效性及毒性筛选或安全性预测研究。本文就ESCs的分化,ESCs在药物安全性研究中的应用,以及ESCs结合代谢组学技术进行药物安全性预测研究的应用进展作一综述。     

人诱导多能干细胞在药物早期毒性评价中的应用

人诱导多能干细胞与人胚胎干细胞相似,在体外可分化为各种类型的体细胞,其来源充足,可针对个人或某种疾病取材,为药物早期毒性评价体外替代方法提供了一个新的可选细胞模型。目前,利用人诱导多能干细胞获得的心肌细胞用于药物引起的心率改变、QT间期延长和心肌损伤等心脏毒性评价;利用其获得的神经细胞,结合高通量、高内涵技术及电生理学技术,可用于药物引起的神经突出生长异常、电生理改变及神经发育毒性评价;利用人诱导多能干细胞可获得个体特异性的大量肝细胞,具有较高的细胞色素P450酶活性,能够比较真实的反映人肝细胞的代谢特征,用于评价药物肝细胞毒性;人诱导多能干细胞具有多能性,在体外可分化为外、中和内胚层,具有用于发育毒性评价的可能性,对三胚层相应标志分子的检测有助于发育毒性评价终点的确立;人诱导多能干细胞还可用作3D培养的种子细胞,构建三维立体组织和器官模型,用于药物早期毒性评价,进一步缩小细胞水平与体内水平评价结果的差异。     

干细胞的研究现状和应用展望

成体干细胞在治疗多种难治性疾病包括中风、神经系统变性性疾病、糖尿病、心脏病,外伤等已开辟了一个新的方向.干细胞是研究细胞自我更新和分化的重要工具,并将在新药发明和药物毒性筛选中发挥作用,对成体干细胞及其分化的研究必将在今后对医学及生物学领域产生极其深远的影响。     

诱导性多能干细胞的研究进展

诱导性多能干细胞(induced pluripotent stem cell,iPSC)是通过将几个特定的转录因子导入分化的体细胞以诱导体细胞重编程而获得的可不断自我更新且具有多向分化潜能的多能干细胞.如同胚胎干细胞,iPSC仍维持未分化状态,可分化为3个胚层来源的所有细胞以参与机体所有组织和器官的形成.这项技术避免了干细胞研究领域的免疫排斥和伦理道德问题,同时为特异性疾病的研究提供了强有力的工具.因此,iPSC研究不仅具有重要的理论研究意义,而且在再生医学及药物筛选与评价方面具有很好的应用价值.     

人胚胎干细胞诱导分化的肝样细胞质量评价研究

肝细胞、肝组织或器官移植是目前不可逆失代偿性肝病的主要治疗手段,而由人胚胎干细胞诱导分化来源的肝样细胞(human embryonic stem cells-derived hepatocyte-like cells,h ESC-HLCs)能为移植提供数量充足、质量可控、来源稳定的细胞。为满足临床应用研究的需要,hESC-HLCs需具备明确的基本生物学属性、微生物学安全性、生物学安全性及生物学有效性的总体质量要求,其中每一类质量要求是由多个关键质量属性所组成。hESC-HLCs的整个制备过程是从人胚胎干细胞(hESCs)向hESC-HLCs的全分化过程,可基本分为4个阶段,各阶段在细胞形态、标志基因/蛋白的表达、生物学功能等方面均有明显的特征。本文就h ESC-HLCs总体质量要求及各质量属性进行讨论,目的是在我国建立临床研究用hESC-HLCs质量评价方法和评价策略。     

脂肪源性干细胞的临床转化研究

脂肪源性干细胞又称脂肪间充质干细胞,是一类处于未定向分化状态并具有自我更新、高度增殖和多向分化潜能的细胞群体,具有一般干细胞的特点,是一种理想的组织工程种子细胞.近年来,对脂肪间充质干细胞的应用研究已经取得了初步进展,其特有的生物学特性为多种疾病的治疗开辟了新的思路.本文就脂肪间充质干细胞的生物学特性及其在临床上的转化研究进行阐述.     

常用细胞毒性药物的配伍稳定性及使用安全性探讨

细胞毒性药物（cytotoxicdrugs,CD）是指在生物学方面具有危害性影响的药品,多为临床常用的抗肿瘤药物,这类药物一旦通过皮肤接触或吸入等方式摄入低剂量就能造成包括生殖、泌尿及肝肾系统的毒害,具有致癌、致畸、生殖毒性。     

组蛋白去乙酰化酶参与调控神经干细胞分化的研究进展

神经干细胞是一种多能干细胞,具有自我更新及多向分化潜能,在一定条件下能分化为神经元、星形胶质细胞、少突胶质细胞。神经干细胞的分化不仅由细胞周围微环境决定,且受基因调控。神经干细胞的分化复杂,其中组蛋白去乙酰化酶[1]结合细胞内转录因子和信号通路可调节神经干细胞的分化,主要影响神经干细胞分化过程中的转录,从而影响细胞的发育。     

间充质干细胞的体内生物分布及其成药性研究进展

间充质干细胞（MSCs）是一类来源于中胚层的多能干细胞,具有多向分化潜能、促进干细胞植入、造血支持、免疫调控及自我复制的生物学特性,是干细胞家族重要成员。由于其免疫调节、血管再生、组织修复等作用,MSCs已逐渐成为多项治疗领域的研究热点之一,并在自身免疫性疾病、组织损伤以及各种替代治疗领域成为一种非常有潜力、有前景的治疗药物。当机体组织损伤或发生炎性细胞浸润时,外源性给予的MSCs进入机体后可归巢至病变部位,并与体内的多种细胞发生相互作用,恢复机体正常生理功能、维持机体微环境稳态,修复病变组织器官。通过综述MSCs进入体内后的分布、归巢特性及相关影响因素、体内外检测方法及其作为药物开发的成药性研究进展,为干细胞从医疗技术转化为药物提供指导。     

Human embryonic stem cell-derived cardiomyocytes: drug discovery and safety pharmacology

Human embryonic stem cells (hESCs) can provide potentially unlimited quantities of a wide range of human cell types that can be used in drug discovery and development, basic research and regenerative medicine. In this review, the authors describe the differentiation of hESCs into cardiomyocytes and outline the properties of hESC-derived cardiomyocytes (hESC-CMs), including their cardiac-type action potentials and contractile characteristics. In vitro cellular assays using hESC-CMs, which can be genetically engineered to create target-specific reporters as well as human disease models, will have applications at multiple stages of the drug discovery process. Furthermore, cardiac safety pharmacology assays evaluating the risk of proarrhythmic side effects associated with QT prolongation may be enhanced in their predictive value with the use of hESC-CMs.     

盘龙七片联合依托考昔治疗膝骨关节炎的临床研究

目的 探讨盘龙七片联合依托考昔治疗膝骨关节炎的临床效果.方法 选取2019年6月—2020年12月天津市第一中心医院收治的134例膝骨关节炎患者,随机分成对照组(67例)和治疗组(67例).对照组口服依托考昔片,1片/次,1次/d.治疗组在对照组基础上口服盘龙七片,3片/次,3次/d.两组连续治疗8周.观察两组患者临床疗效,比较治疗前后两组患者主要症状与体征改善情况,膝骨性关节炎生存质量量表(QOL-KOA)评分,血清白细胞介素-1β(IL-1β)、基质金属蛋白酶-9(MMP-9)、血管内皮生长因子(VEGF)、转化生长因子 β1(TGF-β1)、一氧化氮(NO)水平.结果 治疗后,治疗组总有效率为95.5％,明显高于对照组的85.1％(P<0.05).治疗后,两组患者膝关节疼痛视觉模拟量表(VAS)评分和西安大略和麦克马斯特大学骨关节炎指数(WOMAC)总分均显著低于同组治疗前(P<0.05),晨僵时间显著短于治疗前(P<0.05),且均以治疗组的改善更显著(P<0.05).治疗后,两组QOL-KOA中各项目评分及其总分均显著降低(P<0.05),且治疗组的降低更显著(P<0.05).治疗后,两组血清IL-1β、MMP-9、VEGF和NO含量均显著低于同组治疗前,血清TGF-β1水平均显著高于本组治疗前(P<0.05),且治疗组明显好于对照组(P<0.05).结论 盘龙七片联合依托考昔治疗膝骨关节炎的整体疗效满意,能安全有效地缓解患者症状与体征,提高生活质量.     

Disruption of cardiogenesis in human embryonic stem cells exposed to trichloroethylene

Trichloroethylene (TCE) is ubiquitous in our living environment, and prenatal exposure to TCE is reported to cause congenital heart disease in humans. Although multiple studies have been performed using animal models, they have limited value in predicting effects on humans due to the unknown species‐specific toxicological effects. To test whether exposure to low doses of TCE induces developmental toxicity in humans, we investigated the effect of TCE on human embryonic stem cells (hESCs) and cardiomyocytes (derived from the hESCs). In the current study, hESCs cardiac differentiation was achieved by using differentiation medium consisting of StemPro‐34. We examined the effects of TCE on cell viability by cell growth assay and cardiac inhibition by analysis of spontaneously beating cluster. The expression levels of genes associated with cardiac differentiation and Ca²⁺ channel pathways were measured by immunofluorescence and qPCR. The overall data indicated the following: (1) significant cardiac inhibition, which was characterized by decreased beating clusters and beating rates, following treatment with low doses of TCE; (2) significant up‐regulation of the Nkx2.5/Hand1 gene in cardiac progenitors and down regulation of the Mhc‐7/cTnT gene in cardiac cells; and (3) significant interference with Ca²⁺ channel pathways in cardiomyocytes, which contributes to the adverse effect of TCE on cardiac differentiation during early embryo development. Our results confirmed the involvement of Ca²⁺ turnover network in TCE cardiotoxicity as reported in animal models, while the inhibition effect of TCE on the transition of cardiac progenitors to cardiomyocytes is unique to hESCs, indicating a species‐specific effect of TCE on heart development. This study provides new insight into TCE biology in humans, which may help explain the development of congenital heart defects after TCE exposure. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1372–1380, 2016.     

Generation of human pluripotent stem cell-derived hepatocyte-like cells for drug toxicity screening

Because drug-induced liver injury is one of the main reasons for drug development failures, it is important to perform drug toxicity screening in the early phase of pharmaceutical development. Currently, primary human hepatocytes are most widely used for the prediction of drug-induced liver injury. However, the sources of primary human hepatocytes are limited, making it difficult to supply the abundant quantities required for large-scale drug toxicity screening. Therefore, there is an urgent need for a novel unlimited, efficient, inexpensive, and predictive model which can be applied for large-scale drug toxicity screening. Human embryonic stem (ES) cells and induced pluripotent stem (iPS) cells are able to replicate indefinitely and differentiate into most of the body's cell types, including hepatocytes. It is expected that hepatocyte-like cells generated from human ES/iPS cells (human ES/iPS-HLCs) will be a useful tool for drug toxicity screening. To apply human ES/iPS-HLCs to various applications including drug toxicity screening, homogenous and functional HLCs must be differentiated from human ES/iPS cells. In this review, we will introduce the current status of hepatocyte differentiation technology from human ES/iPS cells and a novel method to predict drug-induced liver injury using human ES/iPS-HLCs.     

Stem cells and small molecule screening: haploid embryonic stem cells as a new tool

Stem cells can both self-renew and differentiate into various cell types under certain conditions, which makes them a good model for development and disease studies. Recently, chemical approaches have been widely applied in stem cell biology by promoting stem cell self-renewal, proliferation, differentiation and somatic cell reprogramming using specific small molecules. Conversely, stem cells and their derivatives also provide an efficient and robust platform for small molecule and drug screening. Here, we review the current research and applications of small molecules that modulate stem cell self-renewal and differentiation and improve reprogramming, as well as the applications that use stem cells as a tool for small molecule screening. Moreover, we introduce the recent advance in haploid embryonic stem cells research. Haploid embryonic stem cells maintain haploidy and stable growth over extensive passages, possess the ability to differentiate into all three germ layers in vitro and in vivo, and contribute to the germlines of chimeras when injected into blastocysts. Androgenetic haploid stem cells can also be used in place of sperm to produce fertile progeny after intracytoplasmic injection into mature oocytes. Such characteristics demonstrate that haploid stem cells are a new approach for genetic studies at both the cellular and animal levels and that they are a valuable platform for future small molecule screening.     

In vitro developmental toxicity test detects inhibition of stem cell differentiation by silica nanoparticles

While research into the potential toxic properties of nanomaterials is now increasing, the area of developmental toxicity has remained relatively uninvestigated. The embryonic stem cell test is an in vitro screening assay used to investigate the embryotoxic potential of chemicals by determining their ability to inhibit differentiation of embryonic stem cells into spontaneously contracting cardiomyocytes.Four well characterized silica nanoparticles of various sizes were used to investigate whether nanomaterials are capable of inhibition of differentiation in the embryonic stem cell test. Nanoparticle size distributions and dispersion characteristics were determined before and during incubation in the stem cell culture medium by means of transmission electron microscopy (TEM) and dynamic light scattering.Mouse embryonic stem cells were exposed to silica nanoparticles at concentrations ranging from 1 to 100 μg/ml. The embryonic stem cell test detected a concentration dependent inhibition of differentiation of stem cells into contracting cardiomyocytes by two silica nanoparticles of primary size 10 (TEM 11) and 30 (TEM 34) nm while two other particles of primary size 80 (TEM 34) and 400 (TEM 248) nm had no effect up to the highest concentration tested.Inhibition of differentiation of stem cells occurred below cytotoxic concentrations, indicating a specific effect of the particles on the differentiation of the embryonic stem cells. The impaired differentiation of stem cells by such widely used particles warrants further investigation into the potential of these nanoparticles to migrate into the uterus, placenta and embryo and their possible effects on embryogenesis.     

Evaluation of developmental toxicity using undifferentiated human embryonic stem cells

An embryonic stem cell test (EST) has been developed to evaluate the embryotoxic potential of chemicals with an in vitro system. In the present study, novel methods to screen toxic chemicals during the developmental process were evaluated using undifferentiated human embryonic stem (hES) cells. By using surface marker antigens (SSEA‐4, TRA‐1‐60 and TRA‐1‐81), we confirmed undifferentiated conditions of the used hES cells by immunocytochemistry. We assessed the developmental toxicity of embryotoxic chemicals, 5‐fluorouracil, indomethacin and non‐embryotoxic penicillin G in different concentrations for up to 7 days. While expressions of the surface markers were not significantly affected, the embryotoxic chemicals influenced their response to pluripotent ES cell markers, such as OCT‐4, NANOG, endothelin receptor type B (EDNRB), secreted frizzled related protein 2 (SFRP2), teratocarcinoma‐derived growth factor 1 (TDGF1), and phosphatase and tensin homolog (PTEN). Most of the pluripotent ES cell markers were down‐regulated in a dose‐dependent manner after treatment with embryotoxic chemicals. After treatment with 5‐fluorouracil, indomethacin and penicillin G, we observed a remarkable convergence in the degree of up‐regulation of development, cell cycle and apoptosis‐related genes by gene expression profiles using an Affymetrix GeneChips. Taken together, these results suggest that embryotoxic chemicals have cytotoxic effects, and modulate the expression of ES cell markers as well as development‐, cell cycle‐ and apoptosis‐related genes that have pivotal roles in undifferentiated hES cells. Therefore, we suggest that hES cells may be useful for testing the toxic effects of chemicals that could impact the embryonic developmental stage. Copyright © 2014 John Wiley & Sons, Ltd.     

Embryonic stem cell application in drug discovery

Embryonic stem (ES) cells and their differentiated progeny offer tremendous potential for regenerative medicine, even in the field of drug discovery. There is an urgent need for clinically relevant assays that make use of ES cells because of their rich biological utility. Attention has been focused on small molecules that allow the precise manipulation of cells in vitro, which could allow researchers to obtain homogeneous cell types for cell-based therapies and discover drugs for stimulating the regeneration of endogenous cells. Such therapeutics can act on target cells or their niches in vivo to promote cell survival, proliferation, differentiation, and homing. In the present paper, we reviewed the use of ES cell models for high-throughput/content drug screening and toxicity assessment. In addition, we examined the role of stem cells in large pharmaceutical companies' R&D and discussed a novel subject, nicheology, in stem cell-related research fields.     

Embryonic stem cells and the next generation of developmental toxicity testing

Introduction: The advent of stem cell technology has seen the establishment of embryonic stem cells (ESCs) as molecular model systems and screening tools. Although ESCs are nowadays widely used in research, regulatory implementation for developmental toxicity testing is pending.

Areas Covered: This review evaluates the performance of current ESC, including human (h)ESC testing systems, trying to elucidate their potential for developmental toxicity testing. It shall discuss defining parameters and mechanisms, their relevance and contemplate what can realistically be expected. Crucially this includes the question of how to ascertain the quality of currently employed cell lines and tests based thereon. Finally, the use of hESCs will raise ethical concerns which should be addressed early on.

Expert Opinion: While the suitability of (h)ESCs as tools for research and development goes undisputed, any routine use for developmental toxicity testing currently still seems premature. The reasons for this comprise inherent biological deficiencies as well as cell line quality and system validation. Overcoming these issues will require collaboration of scientists, test developers and regulators. Also, validation needs to be made worthwhile for academia. Finally we have to continuously rethink existing strategies, making room for improved testing and innovative approaches.