脑出血继发损伤中沉默信息调节因子2的表达和炎症反应*

目的：探讨脑出血对酵母沉默信息调节因子2（Sirt2）和炎症的影响。方法：将胶原酶Ⅳ注入SD大鼠右侧 纹状体中建立脑出血模型，通过免疫印迹和ELISA 等方法测定大鼠脑出血后48 h 的Sirt2 的表达及炎症变化。利 用Hemin 诱导PC12 细胞损伤模拟体外脑出血模型，并检测Sirt2 及炎症变化；采用短发夹RNA（shRNA）-Sirt2 沉 默Sirt2 在PC12 细胞中的表达及对炎症的影响。结果：手术后48 h 脑出血行为学评分最低。脑出血组Sirt2 的表达 显著高于假手术组。脑出血组IL-6、IL-1β 表达显著升高。结论：脑出血可以促进Sirt2 的表达和炎症反应，降低 Sirt2 的表达可减缓炎症反应。 关键词 脑出血；沉默信息调节     

糖尿病视网膜病变中视网膜内皮细胞功能障碍的研究进展北大核心

视网膜内皮细胞(REC)是参与糖尿病视网膜病变和许多眼部疾病的主要细胞类型之一。视网膜微血管系统有助于血-视网膜屏障的维持,这对正常的视功能至关重要。REC的改变在视网膜疾病的发生发展中起着关键作用。高血糖是糖尿病微血管损伤的重要原因,通过不同的机制导致REC功能障碍,包括向衰老表型改变、迁移和增殖能力增强、炎性凋亡等,最终导致无细胞毛细血管及病理性新生血管形成。本文对糖尿病视网膜病变中REC的功能障碍作一综述。     

Silencing KLF16 inhibits oral squamous cell carcinoma cell proliferation by arresting the cell cycle and inducing apoptosis

Krüppel-like factor 16 (KLF16), a member of the Krüppel-like factor (KLF) family, has been extensively investigated in multiple cancer types. However, the role of KLF16 in oral squamous cell carcinoma (OSCC) remains unknown. Thus, we conducted this study to investigate its related mechanism. KLF16 expression in OSCC cell lines was quantified by western blotting. Then, OECM1 and OC3 cells were divided into Blank, siCtrl, siKLF16#1 and siKLF16#2 groups. Subsequently, cell proliferation was detected using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assays, cell migration and invasion were detected with wound healing and Transwell assays, and cell cycle distribution and cell apoptosis were detected via flow cytometry. KLF16, p21, CDK4, Cyclin D1 and p-Rb expression was detected by western blotting. Finally, xenograft models were established in nude mice to observe the in vivo effects of KLF16 on OSCC. KLF16 protein expression was upregulated in OSCC cells. Compared to the cells in the Blank group, the OECM1 and OC3 cells in the siKLF16#1 group and siKLF16#2 group exhibited a sharp decrease in proliferation but a remarkable increase in apoptosis. Moreover, the proportion of cells in the G0/G1 phase notably increased and that in the S phase decreased, with evident decreases in cell invasion and migration. Moreover, KLF16, cyclin-dependent kinase 4 (CDK4), Cyclin D1 and p-Rb protein expression was upregulated, but p21 expression was downregulated. The mice in the siKLF16#1 and siKLF16#2 xenograft model groups exhibited slower tumour growth and smaller tumours with evident downregulation of Ki67 expression compared to the mice in the Blank group. KLF16 expression was upregulated in OSCC cells, and interfering with KLF16 led to cell cycle arrest, inhibited OSCC cell growth and promoted cell apoptosis.     

Inhibition of autophagy enhances apoptosis induced by bortezomib in AML cells

Bortezomib is a novel proteasome inhibitor, which has been successfully used to treat mantle cell lymphoma and multiple myeloma. However, the direct effects of bortezomib on acute promyelocytic leukaemia (APL) have not been fully investigated. In the present study, the WST-8 assay, western blotting, flow cytometry, monodansylcadaverine staining and transmission electron microscopy were performed. It was demonstrated that bortezomib treatment induced a time- and dose-dependent decrease in the viability of NB4 cells. Bortezomib treatment induced cell apoptosis in NB4 cells, as assessed by Annexin V/propidium iodide analysis, and the detection of cleaved caspase-3, cleaved poly(ADP-ribose) polymerase, Bax and Bcl-2 expression. Furthermore, bortezomib treatment induced autophagy in NB4 cells, as indicated by autophagosome formation, p62 degradation, LC3-I to LC3-II conversion and formation of acidic autophagic vacuoles. Notably, autophagy induced by bortezomib was initiated prior to apoptosis. Inhibition of autophagy by knocking down Beclin-1 expression increased bortezomib-induced apoptosis in NB4 cells. Therefore, the present study revealed that the combination of bortezomib and autophagy inhibition may be a potential treatment strategy for APL.     

Apelin-13 inhibits apoptosis and excessive autophagy in cerebral ischemia/reperfusion injury

Apelin-13 is a novel endogenous ligand for an angiotensin-like orphan G-protein coupled receptor, and it may be neuroprotective against cerebral ischemia injury. However, the precise mechanisms of the effects of apelin-13 remain to be elucidated. To investigate the effects of apelin-13 on apoptosis and autophagy in models of cerebral ischemia/reperfusion injury, a rat model was established by middle cerebral artery occlusion. Apelin-13(50 μg/kg) was injected into the right ventricle as a treatment. In addition, an SH-SY5 Y cell model was established by oxygen-glucose deprivation/reperfusion, with cells first cultured in sugar-free medium with 95% N2 and 5% CO2 for 4 hours and then cultured in a normal environment with sugar-containing medium for 5 hours. This SH-SY5 Y cell model was treated with 10–7 M apelin-13 for 5 hours. Results showed that apelin-13 protected against cerebral ischemia/reperfusion injury. Apelin-13 treatment alleviated neuronal apoptosis by increasing the ratio of Bcl-2/Bax and significantly decreasing cleaved caspase-3 expression. In addition, apelin-13 significantly inhibited excessive autophagy by regulating the expression of LC3 B, p62, and Beclin1. Furthermore, the expression of Bcl-2 and the phosphatidylinositol-3-kinase(PI3 K)/Akt/mammalian target of rapamycin(mTOR) pathway was markedly increased. Both LY294002(20 μM) and rapamycin(500 nM), which are inhibitors of the PI3 K/Akt/mTOR pathway, significantly attenuated the inhibition of autophagy and apoptosis caused by apelin-13. In conclusion, the findings of the present study suggest that Bcl-2 upregulation and mTOR signaling pathway activation lead to the inhibition of apoptosis and excessive autophagy. These effects are involved in apelin-13-induced neuroprotection against cerebral ischemia/reperfusion injury, both in vivo and in vitro. The study was approved by the Animal Ethical and Welfare Committee of Jining Medical University, China(approval No. 2018-JS-001) in February 2018.     

Comparison of the protective effects of curcumin and caffeic acid phenethyl ester against doxorubicin-induced testicular toxicity

Whether testicular toxicity is mediated by matrix metalloproteinases (MMPs) is an important question that has not been examined. This study investigated the suppressive effect of curcumin and caffeic acid phenethyl ester (CAPE) on oxidative stress, apoptosis, and whether MMPs mediate doxorubicin (DOX)-induced testicular injury. Male rats were randomly divided into eight groups (n = 8 per group). The groups were as follows: sham, dimethyl sulphoxide (100 µL), DOX (3 mg/kg), CAPE (2.68 mg/kg), curcumin (30 mg/kg), DOX+CAPE (3 mg/kg DOX and 2.68 mg/kg CAPE), DOX+curcumin (3 mg/kg DOX and 30 mg/kg curcumin) and DOX+CAPE+curcumin (3 mg/kg DOX, 2.68 mg/kg CAPE and 30 mg/kg curcumin). Injections were administered daily for 21 days. The oxidative stress, MMPs, proinflammatory cytokines and apoptotic markers in the DOX group were higher than the sham group (p < .05); these measures were lower in the groups treated with CAPE and curcumin together with DOX compared with the DOX group (p < .05). The results showed that MMPs mediated DOX-induced testicular injury, but CAPE and especially curcumin suppressed testis injury and cell apoptosis by suppressing DOX-induced increases in MMPs, oxidative stress and proinflammatory cytokines. However, curcumin exhibited more pronounced effects than CAPE in terms of all studied parameters.     

Antitumor effects of dioscin in A431 cells via adjusting ATM/p53-mediated cell apoptosis,DNA damage and migration

Skin cancer is the deadliest type of malignant disease and causes primary mortality worldwide. Dioscin, which exists in medicinal plants, has potent anticancer effects. However, its effects on skin cancer remain unknown. In the present study, the activity and mechanism of dioscin on the human skin cancer A431 cell line were investigated, MTT, colony formation, Transwell, wound-healing, TUNEL, Comet, immunofluorescence and western blot assays were used to assess the effects of dioscin on A431 cells. The results of MTT, colony formation, Transwell and wound-healing assays revealed that dioscin suppressed proliferation, colony formation and invasion of the cancer cells. TUNEL and comet assays demonstrated that dioscin exhibited significant effects on cell apoptosis and DNA damage. Investigations into the mechanism revealed that the expression levels of phosphorylated Ataxia telangiectasia-mutated (ATM) were considerably activated by dioscin, which significantly upregulated the expression levels of p53 to activate mitochondrial apoptosis signaling. Furthermore, the expression levels of BAX, cleaved caspase-3/9 and cleaved poly (ADP-ribose) polymerase were upregulated, and the expression levels of BCL-2 were downregulated by dioscin. Additionally, dioscin markedly downregulated the expression levels of matrix metalloproteinase 2 (MMP2), MMP9, RHO and cdc42, which are all associated with tumor invasion. In addition, p53-small interfering RNA transfection experiments indicated that dioscin exhibited excellent activity against skin cancer in vitro by decreasing p53 expression. Overall, the present results suggested that dioscin inhibited skin cancer cell proliferation via adjusting ATM/p53-mediated cell apoptosis, migration and DNA damage, which should be considered as a potential option for future treatments of skin cancer.     

弥漫型大B细胞淋巴瘤EZH2、XIAP和Survivin蛋白表达水平及意义

目的探讨弥漫型大B细胞淋巴瘤Zeste同源物增强子2(EZH2)、X连锁凋亡抑制蛋白(XIAP)和生存素(Survivin)蛋白表达水平及意义。方法选取弥漫型大B细胞淋巴瘤组织92例作为观察组,同时选取反应性增生淋巴结组织50例作为对照组,采用免疫组化染色法检测EZH2、XIAP和Survivin蛋白表达。结果观察组EZH2、XIAP和Survivin蛋白阳性表达率分别为77.17%、55.43%和60.87%,明显高于对照组(P<0.05)。观察组临床分期Ⅲ~Ⅳ期EZH2、XIAP和Survivin蛋白表达阳性率分别为90.70%、86.05%和81.40%,明显高于临床分期Ⅰ~Ⅱ期(P<0.05);EZH2与XIAP、Survivin蛋白表达呈正相关(γ=0.547、0.360,P均<0.05),XIAP与Survivin蛋白表达呈正相关(γ=0.581,P<0.05)。结论弥漫型大B细胞淋巴瘤EZH2、XIAP和Survivin蛋白表达水平上调,与临床分期有一定关系,三者间存在相关关系。     

香萱益神方对血管性痴呆模型大鼠神经元凋亡机制研究

目的:探讨香萱益神方治疗血管性痴呆(VD)模型大鼠认知功能作用及其对神经元凋亡机制的研究。方法:两血管阻断法建立VD大鼠模型,给予中药方香萱益神方灌胃治疗6周,分别于造模后、中药喂养6周后进行Morris水迷宫行为学检测,测试大鼠认知行为能力改变,行为学测试结束后,检测VD模型大鼠海马中海马组织脑源性神经营养因子(BDNF)表达水平的变化。结果:香萱益神方治疗6周后,血管性痴呆大鼠模型学习记忆能力得到改善,上调脑内海马组织神经营养因子水平,海马神经元凋亡率下降。结论:香萱益神方是治疗血管性痴呆的有效方剂,可以有效改善VD大鼠模型认知行为功能的障碍情况,起到减少海马神经元细胞凋亡,诱导海马神经元细胞修复的作用。香萱益神方可能是通过激活BDNF相关通路,起到保护海马神经元的作用。     

异牡荆素对非小细胞性肺癌细胞自我更新和凋亡的影响

目的研究异牡荆素(ISO)对非小细胞性肺癌(NSCLC)细胞的影响和潜在的机制。方法将A549和H1650细胞分别分为空白组、低剂量实验组(4μmol·L^-1 ISO)和高剂量实验组(16μmol·L^-1 ISO)。用噻唑蓝法检测NSCLC细胞活性,用肿瘤球形成实验检测NSCLC细胞的细胞球形成率,用Western blot法检测NSCLC细胞凋亡、自我更新、无翅型MMTV整合位点家族/β-连环蛋白(Wnt/β-catenin)信号通路相关蛋白的表达水平。结果与空白组比较,低、高剂量实验组中A549和H1650细胞在24,48和72 h的细胞活性均显著降低。低、高剂量实验组和空白组中A549细胞的细胞球形成率分别为(4.18±0.45)%,(2.01±0.67)%和(6.02±0.57)%,切割的半胱氨酸蛋白酶-3相对表达量分别为0.24±0.08,1.25±0.13和0.06±0.07,SRY相关高迁移率族盒蛋白-2相对表达量分别为0.49±0.04,0.25±0.03和1.00±0.09,Kruppel样因子4相对表达量分别为0.68±0.04,0.44±0.03和1.01±0.06,Wnt1相对表达量分别为0.63±0.06,0.28±0.04和1.00±0.06,β-catenin相对表达量分别为0.41±0.05,0.22±0.03和1.01±0.09;与空白组比较,低、高剂量实验组中A549细胞的上述指标的差异均有统计学意义(P<0.05,P<0.01)。上述3组中H1650细胞的上述指标也呈现一致的现象。结论ISO可能通过抑制Wnt/β-catenin信号通路来抑制NSCLC细胞活性和自我更新,并促进其凋亡。