Human and mouse artificial chromosome technologies for studies of pharmacokinetics and toxicokinetics

In the earliest stage of drug discovery/development, various cell-based models and animal models were used for the prediction of human pharmacokinetics and toxicokinetics. Unfortunately, drugs under development are often discontinued because their nonclinical results do not extrapolate to human clinical studies in relation to either safety or efficacy. Therefore, it is important to improve the time- and cost-effectiveness of drug development. This might be achieved by developing new technologies including pharmacokinetics and toxicokinetics models that use human and mouse artificial chromosome vectors (HACs/MACs). HACs/MACs are unique vectors with several advantages: 1) independent maintenance, 2) defined copy number and mitotically stable, 3) no silencing of the transgene, and 4) no limitation of DNA insertion size. This review provides information on the advantages and examples of the utility of various models based on the recent advances in HAC/MAC technologies, including multifunctional cell-based models for assaying drug–drug interactions, bidirectional permeability, and cytotoxicity, as well as fully genetically humanized mouse models. We also discuss the future prospects of these technologies to advance drug discovery. In summary, these technologies offer advantages over current conventional models and should improve the success rate of drug development related to efficacy and safety for humans.     

GLP体系下对实验动物供应商审核的要求

目的：规范实验动物供应商管理。方法：依据《药物非临床研究质量管理规范》（GLP）等相关法规要求,对实验动物供应商审核相关流程和要求进行了论述。结果与结论：实验动物在药物安全性评价中占有极其重要的地位。通过规范实验动物供应商审核流程,加强动物来源控制,可以有效地提高药物非临床原始资料的有效性和真实性,充分发挥GLP体系下实验动物供应商审核的优越性,保证非临床研究水平。     

The role of glutamate receptors in attention‐deficit/hyperactivity disorder: From physiology to disease

Attention‐deficit hyperactivity disorder (ADHD) is the most common psychiatric disorder in children and adolescents, which is characterized by behavioral problems such as attention deficit, hyperactivity, and impulsivity. As the receptors of the major excitatory neurotransmitter in the mammalian central nervous system (CNS), glutamate receptors (GluRs) are strongly linked to normal brain functioning and pathological processes. Extensive investigations have been made about the structure, function, and regulation of GluR family, describing evidences that support the disruption of these mechanisms in mental disorders, including ADHD. In this review, we briefly described the family and function of GluRs in the CNS, and discussed what is recently known about the role of GluRs in ADHD, that including GluR genes, animal models, and the treatment, which would help us further elucidate the etiology of ADHD.     

阿霉素肾病大鼠podocin mRNA和蛋白的表达

目的观察阿霉素肾病大鼠肾小球上皮细胞足突蛋白podocin mRNA和蛋白的表达。方法肾病组予阿霉素5mg/kg尾静脉注射一次,正常对照组予等量生理盐水尾静脉注射,注射后2周24h尿蛋白定量>30mg为肾病模型成立。观察4周后留24h尿行蛋白定量及血生化检查,并应用半定量RT-PCR和印迹法(Western blotting)测定podocinmRNA和蛋白质的表达。结果正常对照组大鼠podocin蛋白表达的相对量是5·26±1·19,而肾病组大鼠podocin蛋白基本不表达;正常对照组、肾病组podocin分子mRNA的相对值分别为1·06±0·19、1·96±0·98,肾病组大鼠podocinmRNA的表达与正常对照组相比显著上调(P<0·05)。结论阿霉素肾病大鼠蛋白尿的产生可能与podocin蛋白表达的减少有关。     

p185高表达人卵巢癌裸鼠模型的建立

目的 建立高表达p185的人卵巢癌裸鼠模型。方法 BALB／c裸鼠皮下接种高表达p185的人卵巢癌细胞株SKOV3,观察成瘤情况及移植瘤病理组织学特点,并用SP免疫组织化学法测定移植瘤的p185表达情况。结果 12只裸鼠均荷瘤成功,病理组织学与免疫组化均证实移植瘤保持了原细胞系特征。结论 高表达p185人卵巢癌裸鼠模型的成功建立为抗p185抗体药物的体内药效研究提供了理想的平台。     

RNA-Seq analysis in an avian model of maternal phenylketonuria

Cardiac malformations (CVMs) are a leading cause of infant morbidity and mortality. CVMs are particularly prevalent when the developing fetus is exposed to high levels of phenylalanine in-utero in mothers with Phenylketonuria. Yet, elucidating the underlying molecular mechanism leading to CVMs has proven difficult. In this study we used RNA-Seq to investigate an avian model of MPKU and establish differential gene expression (DEG) characteristics of the early developmental stages HH10, 12, and 14. In total, we identified 633 significantly differentially expressed genes across stages HH10, 12, and 14. As expected, functional annotation of significant DEGs identified associations seen in clinical phenotypes of MPKU including CVMs, congenital heart defects, craniofacial anomalies, central nervous system defects, and growth anomalies. Additionally, there was an overrepresentation of genes involved in cardiac muscle contraction, adrenergic signaling in cardiomyocytes, migration, proliferation, metabolism, and cell survival. Strikingly, we identified significant changes in expression with multiple genes involved in Retinoic Acid (RA) metabolism and downstream targets. Using qRTPCR, we validated these findings and identified a total of 42 genes within the RA pathway that are differentially expressed. Here, we report the first elucidation of the molecular mechanisms of cardiovascular malformations in MPKU conducted at early developmental timepoints. We provide evidence suggesting a link between PHE exposure and the alteration of RA pathway. These results are promising and offer novel findings associated with congenital heart defects in MPKU.     

Overview of Protein‐Based Biopolymers for Biomedical Application

Biopolymers are playing a vital role in biomedical applications. Among them, protein‐based biopolymers are utilized for the fabrication of tissue‐engineering constructs, therapeutic molecule delivery carriers, emulsifiers, and food packaging materials. Wide ranges of proteins are extracted from animal or plant sources and are being utilized for the fabrication of scaffolds for regenerative tissue‐engineering application. Here, an overview about the protein structure, extraction procedure, solubility, and various formulation‐based proteins found in the literature are discussed. Biopolymers display several advantages such as biocompatibility and degradability by enzymes. Methods to overcome the disadvantages of these proteins such as immunogenicity, antigenicity, and solubility are reported. Various crosslinking reagents specific to protein chemistry are discussed as well.     

Lost in translation? A critical look at the role that animal models of obsessive compulsive disorder play in current drug discovery strategies

Introduction: Obsessive-compulsive disorder (OCD) is a severe neuropsychiatric illness estimated to affect between 1–3% of the population. In today’s literature, there are a number well-validated and convincing animal models of OCD described.

Areas covered: Herein, the authors look at the role that animal models of OCD (including transgenic models, deer mouse stereotypy, quinpirole sensitization, post-training signal attenuation, and mouse marble burying) have played in determining the current directions of OCD drug discovery. Specifically, the article reviews new OCD drug therapies currently under investigation including drugs that target glutamate, dopamine, serotonin, and endocannabinoid systems. The authors review the published results of these clinical trials, and critically examine the contribution of animal models to the development of these novel therapies.

Expert opinion: Nitric oxide inhibitors, oxycarbazepine, and modulators of serotonin and metabotropic glutamate receptors should be further explored in animal models as well as in clinical trials. Pregabalin, topiramate, lamotrigine, sarcosine, minocycline, L-carnosine, celecoxib, and ondansetron, which have shown promise in clinical trials, should be explored in animal models with the goal of understanding the neurobiology of their effects. A multidisciplinary, interactive approach to OCD drug discovery, where animal models generate neurobiological hypotheses that can be tested in the clinic, and vice versa, should be cultivated.     

草血竭纯化部分对小鼠甲型H1N1流感的疗效

目的探讨草血竭纯化部分对于小鼠甲型H1N1流感的疗效。方法采用滴鼻法建立甲型H1N1流感病毒感染小鼠模型,通过灌胃途径给予不同剂量的草血竭,以给予奥司他韦者为阳性对照,以未给予药物者为病毒对照组。观察14d内小鼠生活状态,计算小鼠肺指数,检测肺组织内流感病毒核酸相对量和病毒滴度。结果甲型H1N1流感病毒对小鼠的半数致死量为10-6。阳性对照组和草血竭高、中剂量组小鼠的存活率均为100%,平均生存日数均为14d,草血竭低剂量组小鼠的存活率为42.86%,平均生存日数为9.14d,而病毒对照组小鼠的存活率及平均生存日数分别为0和3.57d。不同组别小鼠平均生存日数比较,差异有统计学意义(F=8.53,P=0.02);阳性对照组、高剂量组、中剂量组、低剂量组小鼠平均生存日数均高于病毒对照组(P0.05)。阳性对照组和草血竭高剂量、中剂量、低剂量组及病毒对照组肺指数分别为:(0.84±0.07)%、(0.81±0.07)%、(0.84±0.10)%、(0.84±0.10)%和(1.42±0.12)%,差异有统计学意义(P=0.03);病毒核酸相对量分别为:0.37±0.11、0.42±0.06、0.42±0.06、0.65±0.19和1.00±0.06,差异有统计学意义(P=0.04);病毒滴度分别为:2.49±0.12、2.35±0.29、2.43±0.15、2.46±0.12和2.80±0.16,差异有统计学意义(P=0.04)。阳性对照组和草血竭各剂量组的肺指数、肺组织内流感病毒核酸相对量和病毒滴度均低于病毒对照组(P0.05);而阳性对照组的上述指标与草血竭各剂量组比较,差异无统计学意义(P0.05)。结论草血竭纯化部分在体内对甲型H1N1流感病毒具有抑制作用,能够改善甲型H1N1流感小鼠的肺组织的病变,降低病死率。     

角类动物药DNA提取方法研究

目的建立角类动物药材的DNA提取方法,使提取的DNA质量满足PCR及测序要求,同时可用于陈旧动物角类样品的DNA提取。方法为避免取骨塞部位用EDTA脱钙造成DNA提取不完全或DNA被破坏,取角质层部位,采用二硫苏糖醇(DTT)结合化学试剂盒中的细胞裂解液及蛋白酶K处理角质层样本,其余按试剂盒操作提取DNA。考察了取样量、DTT用量对角质部位DNA质量的影响。结果确定了取样量为25 mg,DTT用量为20μL,角质细胞裂解完全,所有样品的DNA质量均可满足PCR要求。结论建立的DNA提取方法,提取DNA完全,可标准化操作,可应用于多种动物角的提取。