The Protective Role of Bmal1-Regulated Autophagy Mediated by HDAC3/SIRT1 Pathway in Myocardial Ischemia/Reperfusion Injury of Diabetic Rats

Cardiovascular Drugs and Therapy - Histone deacetylase 3 (HDAC3) and silent information regulator 1 (SIRT1) are histone deacetylases that regulate important metabolic pathways and play important...     

乌司他丁保护百草枯中毒大鼠肺免受损伤的作用

目的:探讨乌司他丁保护百草枯中毒大鼠肺免受损伤的作用及其机制。方法:Wistar大鼠108只,随机分为对照组、百草枯组和乌司他丁组。百草枯组和乌司他丁组给予百草枯灌胃染毒,对照组给予无菌生理盐水灌胃,乌司他丁组同时给予乌司他丁治疗。1、3、7、14、21、28 d测血清中的MDA、SOD、IL-6、IL-10和TNF-α水平,以及肺组织中的p38 MAPK、MMP-2和TIMP-1表达水平。结果:1、3、7 d百草枯组和乌司他丁组的SOD均较对照组下降(P0.01),乌司他丁组SOD明显高于百草枯组(P0.05)。1、3、7 d百草枯组和乌司他丁组的MDA、IL-6、IL-10及TNF-α均较对照组增高(P0.01),乌司他丁组各指标明显低于百草枯组(P0.05)。1、3、7、14、21、28d百草枯组和乌司他丁组肺组织中的p38 MAPK及TIMP-1均较对照组增高(P0.01),乌司他丁组各指标明显低于百草枯组(P0.05)。1、3、7、14、21 d百草枯组和乌司他丁组肺组织中的MMP-2均较对照组增高(P0.01),乌司他丁组MMP-2明显低于百草枯组(P0.05)。结论:乌司他丁通过抑制p38 MAPK信号通路及抗炎、抗氧化作用保护百草枯中毒大鼠肺免受损伤的作用。     

骨桥蛋白通过内质网应激诱导C2C12肌细胞胰岛素抵抗

目的:探讨骨桥蛋白(osteopontin,OPN)对C2C12肌细胞胰岛素抵抗的影响及其可能的机制。方法:低血清培养辅以胰岛素处理诱导C2C12成肌细胞分化为C2C12肌细胞,蛋白免疫印迹检测蛋白质的表达,离心法分离细胞膜,葡萄糖摄取试剂盒定量葡萄糖摄取。结果:(1)骨桥蛋白以剂量依赖和时间依赖方式抑制胰岛素刺激的蛋白激酶B(Akt)的磷酸化,并抑制胰岛素所致的葡萄糖转运体4(Glut4)膜位移和葡萄糖的摄取;而特异性的抗OPN受体CD44抗体预处理可逆转上述变化。(2)OPN可诱导C2C12肌细胞的内质网应激,并促进c-Jun氨基端激酶(JNK)的磷酸化。(3)内质网应激抑制剂4-苯基丁酸(4-PBA)可降低OPN所增加的JNK磷酸化,恢复胰岛素刺激所致的Glut4的膜位移以及葡萄糖摄取。结论:骨桥蛋白通过诱导C2C12肌细胞内质网应激导致胰岛素抵抗。本研究为揭示骨桥蛋白在胰岛素抵抗和糖尿病中的作用提供了新的实验依据和理论解释。     

白细胞介素21在小鼠病毒性心肌炎中的表达及其与抗ANT抗体的相关性

目的:观察病毒性心肌炎(VMC)小鼠急性期不同时点白细胞介素21(IL-21)的表达及其与抗腺嘌呤核苷酸转位子(adenine nucleotide translocator,ANT)抗体的相关性,探究其在VMC发病中的作用及意义。方法:BALB/c小鼠腹腔注射柯萨奇病毒B3(CVB3)建立VMC模型,腹腔注射等量PBS的BALB/c小鼠作为对照组,在注射的第0、1、2、3、4和6周,应用荧光定量逆转录-聚合酶链反应(qRT-PCR)检测小鼠心肌组织中IL-21mRNA的表达、酶联免疫双夹心抗体法(ELISA)检测血清IL-21蛋白及抗ANT抗体的表达。结果:与对照组比较,VMC小鼠心肌组织中IL-21mRNA及血清中IL-21自1周开始高表达,2周时达峰值,并维持高表达至6周,各时点表达量均高于相应时点的对照组(P<0.05)。血清中抗ANT抗体在第1周时开始升高,2周时达峰值,维持高水平表达至第6周,除0周时点外,VMC小鼠与对照组小鼠比较差异均有统计学意义(P<0.05),Pearson相关分析显示,IL-21与抗ANT抗体存在相关性(r=0.88,P<0.01)。结论:IL-21在VMC小鼠心肌组织及外周血中高表达,并与血清抗ANT抗体呈正相关,提示IL-21参与VMC的发病过程。     

银杏叶提取物对实验性自身免疫性脑脊髓炎大鼠的作用研究

目的:建立雌性Wistar大鼠实验性自身免疫性脑脊髓炎(experimental autoimmune encephalomyelitis,EAE)模型,观察银杏叶提取物EGb761腹腔注射对EAE大鼠的可能疗效及神经保护作用和机制。方法:建立Wistar大鼠EAE模型,腹腔注射EGb761(70 mg/kg),连续7 d,于免疫后第14 d和第31 d取颈膨大,分别进行HE、LFB和改良BLS染色,观察各组大鼠炎细胞浸润、髓鞘脱失和轴突缺失情况。结果:(1)EGb761组与EAE组相比临床评分明显减低(P0.05);(2)HE染色显示:EGb761组炎症浸润与EAE组相比明显减低(P0.01);(3)LFB染色显示:EGb761脱髓鞘评分与EAE组相比明显降低(P0.05);(4)改良Bielschowsky染色显示:EGb761组高峰期轴突平均缺失面积与EAE组相比明显下降(P0.01)。结论:EGb761通过减轻炎细胞浸润、促进髓鞘再生和防止轴突缺失,从而对EAE大鼠临床症状的改善起到一定作用。     

单、双侧接骨板内固定治疗干骺端粉碎股骨远端骨折的生物力学比较

目的 比较单、双侧接骨板治疗干骺端粉碎股骨远端骨折的生物力学稳定性。方法22根人工股骨标本建立干骺端粉碎股骨远端骨折（AO分型：C2.3）模型,随机分成2组,每组11根。单钢板组用外侧远端解剖锁定板固定,双钢板组外侧用远端解剖锁定板、内侧用直型锁定接骨板固定。每组标本中5根进行垂直加压,3根进行循环垂直加压测试,检测干骺端内侧间隙压缩位移,剩余3根进行极限加压测试,记录固定失败时的最大负荷。结果 垂直加压测试中,单钢板组平均内侧压缩位移为(2.61±0.28) mm,双钢板组为(0.46±0.08) mm。循环垂直加压测试中,单钢板组平均内侧压缩位移为(1.56±0.12) mm,双钢板组为(0.43±0.05) mm。极限加压测试中,单钢板组平均最大负荷为(5 567±338) N,双钢板组为(9 147±186) N,每组差异都有统计学意义（P<0.05)。结论 双钢板固定干骺端粉碎股骨远端骨折的内侧抗压缩能力较单钢板固定显著增强,使股骨远端内侧结构更加稳定,有助于病人早期功能康复锻炼。     

腹腔镜微创手术与传统开腹手术对结直肠癌患者免疫和生理功能影响的临床观察

目的 探讨对于临床确诊为结直肠癌患者采用腹腔镜手术较传统开放手术的免疫和生理反应方面的影响.方法 选取2013年6月至2014年6月经临床确诊为结直肠癌并于我院消化外科采用腹腔镜手术治疗的50例患者为观察组,同期采用传统开腹手术进行治疗的50例患者为对照组,比较分析两组患者的免疫和生理反应的变化.结果 与对照组比较,术后7天CD4/CD3、术后3天IgM在观察组中升高、术后3天IL-6和CPR在观察组中降低,差异具有统计学意义(P＜0.01);与对照组比较,术后7天TNF-α在观察组中降低,差异具有统计学意义(P＜0.05).在生理功能的比较中,观察组患者在胃动素和胃泌素的分泌方面优于对照组,差异具有统计学意义(P＜0.05).结论 因腹腔镜手术对患者的免疫和生理功能的损伤小,更有利于健康的恢复,值得在临床上推广使用.     

DAB2IP基因沉默引起膀胱癌细胞辐射耐受与化疗抵抗

目的 观察DAB2IP基因对膀胱癌细胞放化疗敏感性的影响.方法 RNA干扰建立DAB2IP表达抑制的膀胱癌细胞,克隆形成实验比较不同DAB2IP表达的细胞对射线放射敏感性的差异,噻唑蓝方法检测不同DAB2IP表达的细胞对常用化疗药物敏感性的变化.结果 DAB2IP基因沉默造成细胞对射线与化疗药物均出现耐受.结论 DAB2IP可能用作预测膀胱癌患者放射或化学治疗预后的分子标志物.     

Precision Medicine Approaches to Vascular Disease: JACC Focus Seminar 2/5

In this second of a 5-part Focus Seminar series, we focus on precision medicine in the context of vascular disease. The most common vascular disease worldwide is atherosclerosis, which is the primary cause of coronary artery disease, peripheral vascular disease, and a large proportion of strokes and other disorders. Atherosclerosis is a complex genetic disease that likely involves many hundreds to thousands of single nucleotide polymorphisms, each with a relatively modest effect for causing disease. Conversely, although less prevalent, there are many vascular disorders that typically involve only a single genetic change, but these changes can often have a profound effect that is sufficient to cause disease. These are termed “Mendelian vascular diseases,” which include Marfan and Loeys-Dietz syndromes. Given the very different genetic basis of atherosclerosis versus Mendelian vascular diseases, this article was divided into 2 parts to cover the most promising precision medicine approaches for these disease types.     

Layered hydrogels accelerate iPSC-derived neuronal maturation and reveal migration defects caused by MeCP2 dysfunction

Probing a wide range of cellular phenotypes in neurodevelopmental disorders using patient-derived neural progenitor cells (NPCs) can be facilitated by 3D assays, as 2D systems cannot entirely recapitulate the arrangement of cells in the brain. Here, we developed a previously unidentified 3D migration and differentiation assay in layered hydrogels to examine how these processes are affected in neurodevelopmental disorders, such as Rett syndrome. Our soft 3D system mimics the brain environment and accelerates maturation of neurons from human induced pluripotent stem cell (iPSC)-derived NPCs, yielding electrophysiologically active neurons within just 3 wk. Using this platform, we revealed a genotype-specific effect of methyl-CpG-binding protein-2 (MeCP2) dysfunction on iPSC-derived neuronal migration and maturation (reduced neurite outgrowth and fewer synapses) in 3D layered hydrogels. Thus, this 3D system expands the range of neural phenotypes that can be studied in vitro to include those influenced by physical and mechanical stimuli or requiring specific arrangements of multiple cell types.Neuronal migration and maturation is a key step in brain development. Defects in this process have been implicated in many disorders, including autism (1) and schizophrenia (2). Thoroughly understanding how neural progenitor cell (NPC) migration is affected in neurodevelopmental disorders requires a means of dissecting the process using cells with genetic alterations matching those in patients. Existing in vitro assays of migration generally involve measurement of cell movement across a scratch or gap or through a membrane toward a chemoattractant in 2D culture systems. Although widely used, such assays may not accurately reveal in vivo differences, as neuronal migration is tightly regulated by physical and chemical cues in the extracellular matrix (ECM) that NPCs encounter as they migrate.In vitro 3D culture systems offer a solution to these limitations (3–7). Compared with 2D culture, a 3D arrangement allows neuronal cells to interact with many more cells (4); this similarity to the in vivo setting has been shown to lengthen viability, enhance survival, and allow formation of longer neurites and more dense networks in primary neurons in uniform matrices or aggregate culture (8, 9). Indeed, 3D culture systems have been used to study nerve regeneration, neuronal and glial development (10–12), and amyloid-β and tau pathology (13). Thus, measuring neuronal migration through a soft 3D matrix would continue this trend toward using 3D systems to study neuronal development and pathology.We sought to develop a 3D assay to examine potential migration and neuronal maturation defects in Rett syndrome (RTT), a genetic neurodevelopmental disorder that affects 1 in 10,000 children in the United States and is caused by mutations in the X-linked methyl-CpG-binding protein-2 (MECP2) gene (14). Studies using induced pluripotent stem cells (iPSCs) from RTT patients in traditional 2D adherent culture have revealed reduced neurite outgrowth and synapse number, as well as altered calcium transients and spontaneous postsynaptic currents (1). However, 2D migration assays seemed unlikely to reveal inherent defects in this developmental process, which could be affected because MeCP2 regulates multiple developmental related genes (15). Migration of RTT iPSC-derived NPCs has not previously been studied.Using a previously unidentified 3D tissue culture system that allows creation of layered architectures, we studied differences in migration of MeCP2-mutant iPSC-derived versus control iPSC-derived NPCs. This approach revealed a defect in migration of MeCP2-mutant iPSC-derived NPCs induced by either astrocytes or neurons. Further, this 3D system accelerated maturation of neurons from human iPSC-derived NPCs, yielding electrophysiologically active neurons within just 3 wk. With mature neurons derived from RTT patients and controls, we further confirmed defective neurite outgrowth and synaptogenesis in MeCP2-mutant neurons. Thus, this 3D system enables study of morphological features accessible in 2D system as well as previously unexamined phenotypes.