精子的表观遗传学研究进展

表观遗传学是研究DNA序列未发生变化但表型却发生可遗传改变的一门学科，其研究内容包括DNA甲基化、组蛋白修饰、非编码RNA调控等几个方面，任何一方面异常都可能影响染色质的结构和基因表达。在精子发生及受精过程中表观遗传信息都发生了较大变化，因此了解精子的表观遗传学变化对研究后代遗传信息的改变至关重要。本文对精子的表观遗传学信息进行综述，并对辅助生殖技术所带来的遗传风险作简要探讨。     

精子的表观遗传学与胚胎发育关系的研究进展

表观遗传学是研究DNA序列未发生变化但表型发生可遗传改变的一门学科。精子在其发生和受精过程中表观遗传信息都发生了较大变化,而这些改变将直接影响受精后的胚胎发育,因此研究精子的表观遗传学与胚胎发育有重要的意义。本文从精子的DNA甲基化、组蛋白修饰、非编码RNA调控和基因印记4个方面对精子的表观遗传学改变及其对胚胎发育的影响作简要探讨。     

表观遗传学与肾脏疾病

表观遗传学(epigenetics)研究的是在DNA序列不发生改变的情况下,基因的表达和功能发生改变,并产生可遗传的表型.表观遗传学研究内容包括DNA甲基化、组蛋白修饰和非编码RNA.在肿瘤发生机制及治疗方面表观遗传学已作出很大的贡献,但在肾脏病领域表观遗传学应用的研究还很少. 一、表观遗传学 表观遗传学是传统遗传学的分支,由英国科学家Waddington提出[1],指在DNA序列不发生改变的情况下,基因的表达和功能发生改变,并产生可遗传的表型.表观遗传学大大丰富了传统遗传学的内容,使我们认识到基因组不仅包括DNA序列遗传信息,还包括表观遗传学信息.     

精子非编码小RNA介导获得性状跨代遗传的研究进展

人类精子RNA的存在已被证实,其在改变早期胚胎事件中发挥着重要作用。近年来的研究表明,父代饮食结构、应激状态等环境暴露因素可以改变非编码小RNA表达水平,从而作为父代遗传信息传递的携带者及表观遗传的标记物,改变早期胚胎发育和子代生长状况,介导获得性状的跨代遗传,这从非编码小RNA的角度,为精子表观遗传学研究提供了新的靶点。在众多研究中,精子piRNA、microRNA、tRNA的研究成果尤为显著,其广泛存在于雄性生殖细胞中,可通过相应的调控机制,介导获得性状的跨代遗传。本文将着重阐述上述3种非编码小RNA在精子表观遗传学研究中所取得的进展,为男性生殖医学研究提供新的视野。     

临床肾脏学中表观遗传学的研究

表观遗传学(Epigenetios)是研究不涉及DNA序列变化,表型却发生可遗传改变的一门不同于遗传学的新学科,其研究内容包括DNA甲基化和组蛋白修饰等几个方面,任何一方面的异常都可能影响染色质的结构与基因表达.慢性肾脏疾病(Chronic kidney disease,CKD)是一种复杂性综合疾病,它受到遗传因素和表观遗传修饰的双重影响.尿毒症患者炎症、血脂异常、高同型半胱氨酸血症、氧化应激水平都可能导致整体DNA甲基化异常.目前,对于CKD的研究尚处于初期,本文就CKD相关的表观遗传学研究作一综述.     

临床肾脏学中表观遗传学的研究

表观遗传学(Epigenetios)是研究不涉及DNA序列变化,表型却发生可遗传改变的一门不同于遗传学的新学科,其研究内容包括DNA甲基化和组蛋白修饰等几个方面,任何一方面的异常都可能影响染色质的结构与基因表达.慢性肾脏疾病(Chronic kidney disease,CKD)是一种复杂性综合疾病,它受到遗传因素和表观遗传修饰的双重影响.尿毒症患者炎症、血脂异常、高同型半胱氨酸血症、氧化应激水平都可能导致整体DNA甲基化异常.目前,对于CKD的研究尚处于初期,本文就CKD相关的表观遗传学研究作一综述.     

组蛋白修饰对炎症反应的调控

表观遗传学（epigenetics）是指在基因的DNA序列不发生改变的情况下,基因的表达水平与功能发生改变,并产生可遗传表型的遗传现象。表观遗传学的研究内容主要包括DNA甲基化、组蛋白修饰、染色质重塑和非编码RNA调控等。     

肥胖导致男性不育的表观遗传机制研究进展

肥胖引发表观遗传改变可导致男性出现不育表型。关于肥胖与男性不育的关系问题,早期研究多集中于内分泌方面。近年研究发现肥胖还可以引发机体表观遗传改变,如DNA甲基化,残余组蛋白修饰,小RNA等,影响精子成熟发育。DNA甲基化是胞嘧啶-磷酸-鸟嘌呤二核苷酸的胞嘧啶残基上的调节标记,肥胖导致DNA甲基化异常,并改变mRNA表达丰度,还可以影响印记基因表达出现印记基因病。残余组蛋白修饰方式包括甲基化、乙酰化等,它们可以相互作用或协同作用,以保证精子正常生长发育。肥胖可以改变甲基化酶及乙酰化酶活性,直接影响残余组蛋白的甲基化和乙酰化;还可以影响精子小RNA的表达,导致精子缺陷。本文就肥胖引起的表观遗传学改变及导致男性不育的作用机制做逐一综述。     

表观遗传学与乳腺癌

表观遗传学是基于非DNA序列改变而产生的基因表达的变化,与肿瘤的发生密切相关,具有可逆性和遗传性,主要包括DNA甲基化、组蛋白修饰和染色体重组,它们相互作用,影响基因表达。乳腺癌中,表观遗传调节改变了一些重要基因的表达,导致了肿瘤的产生和发展。表观遗传学的研究对乳腺癌的发生、发展、早期诊断、预后评估、治疗和复发监测产生了深远的影响。     

乳腺癌基因甲基化的研究进展

乳腺癌的发生的分子机制仍然不明确。研究显示表观遗传学改变（Epigenetics）所导致的基因表达异常也是乳腺癌发生、发展的重要原因。表观遗传学改变是基因的核苷酸序列不发生改变的情况下基因表达的可遗传的变化,包括DNA甲基化、组蛋白乙酰化、染色质重塑、基因组印记以及非编码RNA等。乳腺腺的DNA甲基化是常见的分子事件,具有独特的DNA甲基化特征,既往的研究发现DNA甲基化可以作为乳腺癌早期诊断、分型、监测药物治疗效果和预后的分子标志物。本文将对DNA甲基化在乳腺癌的研究进展进行综述。     

Non-genetic contributions of the sperm nucleus to embryonic development

Recent data from several laboratories have provided evidence that the newly fertilized oocyte inherits epigenetic signals from the sperm chromatin that are required for proper embryonic development. For the purposes of this review, the term epigenetic is used to describe all types of molecular information that are transmitted from the sperm cell to the embryo. There are at least six different forms of epigenetic information that have already been established as being required for proper embryogenesis in mammals or for which there is evidence that it may do so. These are (i) DNA methylation; (ii) sperm-specific histones, (iii) other chromatin-associated proteins; (iv) the perinuclear theca proteins; (v) sperm-born RNAs and, the focus of this review; and (vi) the DNA loop domain organization by the sperm nuclear matrix. These epigenetic signals should be considered when designing protocols for the manipulation and cryopreservation of spermatozoa for assisted reproductive technology as necessary components for effective fertilization and subsequent embryo development.     

血管疾病的表观遗传学研究进展

表观遗传学指独立于DNA核苷酸序列本身的基因表达的可遗传改变,其主要机制包括DNA甲基化、组蛋白修饰和非编码RNA等,这些机制共同作用调控基因的特异性表达。血管疾病是由环境因素和遗传因素相互作用引发的一种慢性疾病。近年来,越来越多的研究证实表观遗传调节在血管疾病的发生发展中具有重要的作用。本文对表观遗传学在血管疾病中的最新研究进展进行综述。     

The role of epigenetic alterations in pancreatic cancer

The past several years have witnessed an explosive increase in our knowledge about epigenetic features in human cancers. It has become apparent that pancreatic cancer is an epigenetic disease, as it is a genetic disease, characterized by widespread and profound alterations in DNA methylation. The introduction of genome-wide screening techniques has accelerated the discovery of a growing list of genes with abnormal methylation patterns in pancreatic cancer, and some of these epigenetic events play a role in the neoplastic process. The detection and quantification of DNA methylation alterations in pancreatic juice is likely a promising tool for the diagnosis of pancreatic cancer. The potential reversibility of epigenetic changes in genes involved in tumor progression makes them attractive therapeutic targets, but the efficacy of epigenetic therapies in pancreatic cancer, such as the use of DNA methylation inhibitors, remains undetermined. In this review, we briefly summarize recent research findings in the field of pancreatic cancer epigenetics and discuss their biological and clinical implications.     

Epigenetic alterations in autoimmune rheumatic diseases

The potential roles of epigenetic alterations in the pathogenesis of autoimmune rheumatic diseases are raising great expectations among clinicians and researchers. Epigenetic mechanisms regulate gene expression and are sensitive to external stimuli, bridging the gap between environmental and genetic factors. Considerable evidence of epigenetic changes, particularly altered patterns of DNA methylation, exists in diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis. The importance of such changes in the pathology of rheumatic diseases has been demonstrated by examining the relationship between gene-specific methylation and SLE in monozygotic twins discordant for the disease, in whom genetic variability is excluded as a cause for discordance. Several studies have highlighted the importance of the tissue-specificity of DNA methylation changes, an aspect which-in contrast with genetic analysis-must be considered when designing epigenetic studies. Here I discuss the proposed mechanisms and implications of DNA methylation changes in the pathogenesis of autoimmune rheumatic diseases, the prospects for future epigenetic studies in rheumatology, the relevance of specific DNA methylation markers and the potential use of drugs with an epigenetic effect in the clinical management of these diseases.     

前列腺癌的表观遗传学研究进展

前列腺癌是男性最常见的恶性肿瘤之一,其病因和发病机制尚不清楚。表观遗传参与了前列腺癌病程的各个阶段,与前列腺癌的发生、发展及转移密切相关,其中DNA甲基化和组蛋白修饰是前列腺癌中最为重要的两种表观遗传表现形式。DNA异常甲基化对肿瘤发生影响机制主要有:基因组广泛性低甲基化、局部过度甲基化、基因突变热点,与前列腺癌DNA损伤修复、激素应答、肿瘤细胞浸润/转移、细胞周期调控等过程密切相关。而组蛋白修饰的异常则将引起相应染色体结构和基因转录水平改变,影响细胞周期、分化和凋亡,导致前列腺癌的发生。目前已有一些针对前列腺癌表观遗传改变的治疗,主要有DNA甲基化转移酶和组蛋白去乙酰化酶抑制剂,并取得了一定的效果。相信随着对表观遗传学研究的深入,必将为前列腺癌的治疗开辟一条新思路。     

The effects of diabetes on male fertility and epigenetic regulation during spermatogenesis

The effects of diabetes mellitus include long-term damages, dysfunctions, and failures of various organs. An important complication of diabetes is the disturbance in the male reproductive system. Glucose metabolism is an important event in spermatogenesis. Moreover, glucose metabolism is also important for maintaining basic cell activity, as well as specific functions, such as motility and fertilization ability in mature sperm. Diabetic disease and experimentally induced diabetes both demonstrated that either type 1 diabetes or type 2 diabetes could have detrimental effects on male fertility, especially on sperm quality, such as sperm motility, sperm DNA integrity, and ingredients of seminal plasma. Epigenetic modifications are essential during spermatogenesis. The epigenetic regulation represents chromatin modifications including DNA methylation, histone modifications, remodeling of nucleosomes and the higher-order chromatin reorganization and noncoding RNAs. If spermatogenesis is affected during the critical developmental window, embryonic gonadal development, and germline differentiation, environmentally-induced epigenetic modifications may become permanent in the germ line epigenome and have a potential impact on subsequent generations through epigenetic transgenerational inheritance. Diabetes may influence the epigenetic modification during sperm spermatogenesis and that these epigenetic dysregulation may be inherited through the male germ line and passed onto more than one generation, which in turn may increase the risk of diabetes in offspring.     

神经病理性疼痛的表观遗传学发展方向

背景 神经病理性疼痛(neuropathic pain,NP)是由神经系统的损害或炎症引起的一种常见而特殊的慢性疼痛,以痛觉过敏、异常痛敏和自发痛为特征.目前发病机制不清,发病率逐年上升,处理非常棘手而且目前的治疗方法疗效不佳,是医学领域的挑战性研究课题. 目的 综述表观遗传学在疼痛中的研究状况. 内容 主要对表观遗传学的基本原理、生物学作用以及表观遗传学在疼痛中的研究进展进行综述. 趋向 表观遗传学在NP中的作用将为人们进一步深入阐明疼痛机制提供新的思路,为NP的治疗提供新的策略.     

Exercise attenuates low back pain and alters epigenetic regulation in intervertebral discs in a mouse model

BACKGROUND CONTEXTChronic low back pain (LBP) is a multifactorial disorder with complex underlying mechanisms, including associations with intervertebral disc (IVD) degeneration in some individuals. It has been demonstrated that epigenetic processes are involved in the pathology of IVD degeneration. Epigenetics refers to several mechanisms, including DNA methylation, that have the ability to change gene expression without inducing any change in the underlying DNA sequence. DNA methylation can alter the entire state of a tissue for an extended period of time and thus could potentially be harnessed for long-term pain relief. Lifestyle factors, such as physical activity, have a strong influence on epigenetic regulation. Exercise is a commonly prescribed treatment for chronic LBP, and sex-specific epigenetic adaptations in response to endurance exercise have been reported. However, whether exercise interventions that attenuate LBP are associated with epigenetic alterations in degenerating IVDs has not been evaluated.PURPOSEWe hypothesize that the therapeutic efficacy of physical activity is mediated, at least in part, at the epigenetic level. The purpose of this study was to use the SPARC-null mouse model of LBP associated with IVD degeneration to clarify (1) if IVD degeneration is associated with altered expression of epigenetic regulatory genes in the IVDs, (2) if epigenetic regulatory machinery is sensitive to therapeutic environmental intervention, and (3) if there are sex-specific differences in (1) and/or (2).STUDY DESIGNEight-month-old male and female SPARC-null and age-matched control (WT) mice (n=108) were assigned to exercise (n=56) or sedentary (n=52) groups. Deletion of SPARC is associated with progressive IVD degeneration and behavioral signs of LBP. The exercise group received a circular plastic home cage running wheel on which they could run freely. The sedentary group received an identical wheel secured in place to prevent rotation. After 6 months, the results obtained in each group were compared.METHODSAfter 6 months of exercise, LBP-related behavioral indices were determined, and global DNA methylation (5-methylcytosine) and epigenetic regulatory gene mRNA expression in IVDs were assessed. This project was supported by the Canadian Institutes for Health Research. The authors have no conflicts of interest.RESULTSLumbar IVDs from WT sedentary and SPARC-null sedentary mice had similar levels of global DNA methylation (%5-mC) and comparable mRNA expression of epigenetic regulatory genes (Dnmt1,3a,b, Mecp2, Mbd2a,b, Tet1-3) in both sexes. Exercise attenuated LBP-related behaviors, decreased global DNA methylation in both WT (p<.05) and SPARC-null mice (p<.01) and reduced mRNA expression of Mecp2 in SPARC-null mice (p<.05). Sex-specific effects of exercise on expression of mRNA were also observed.CONCLUSIONSExercise alleviates LBP in a mouse model. This may be mediated, in part, by changes in the epigenetic regulatory machinery in degenerating IVDs. Epigenetic alterations due to a lifestyle change could have a long-lasting therapeutic impact by changing tissue homeostasis in IVDs.CLINICAL SIGNIFICANCEThis study confirmed the therapeutic benefits of exercise on LBP and suggests that exercise results in sex-specific alterations in epigenetic regulation in IVDs. Elucidating the effects of exercise on epigenetic regulation may enable the discovery of novel gene targets or new strategies to improve the treatment of chronic LBP.