PNPLA3在实验性非酒精性脂肪性肝病中的表达及其CpG岛甲基化状态的研究

目的:探讨PNPLA3在非酒精性脂肪性肝病中的表达水平及其Cp G岛甲基化状态,探讨PNPLA3在NAFLD发生、发展中的作用。方法:1.采用10μg/m L的油酸作用于人正常肝细胞株L02建立脂肪肝细胞模型,72 h后经油红O染色,观察正常组、脂肪肝模型组及给药组细胞内脂滴形成情况,并用荧光定量PCR检测PNPLA3在三组肝细胞中的表达情况。2.采用专用DNA提取试剂盒分别提取正常组、脂肪肝模型组、给药组细胞中DNA,经亚硫酸转化后行PCR扩增目的基因,并用焦磷酸测序方法检测不同组PNPLA3 Cp G岛中甲基化水平,探讨其在非酒精性脂肪肝中的作用。结果:1、脂肪肝模型组肝细胞PNPLA3 m RNA的表达高于正常组,经姜黄素给药后,其表达降低,差异均有统计学意义(P0.05)。2、在PNPLA3启动子区6个检测位点中,脂肪肝组位点2甲基化水平高于正常组,姜黄素给药后甲基化水平降低,差异均有统计学意义(P0.05),在其余各检测位点中甲基化水平无差异。结论:1、油红O染色后,脂肪肝模型组细胞内发现有大量红色脂滴积聚,而正常组基本上未见脂滴,姜黄素给药组脂滴较模型组减少,表明用10μg/m L的油酸诱导能成功建立体外肝细胞模型。2、PNPLA3 m RNA在肝细胞中高表达及其启动子区甲基化状态异常参与非酒精性脂肪肝发病。3、抑制肝脏PNPLA3活性或降低肝细胞PNPLA3 m RNA的表达水平可能是今后治疗非酒精性脂肪性肝病(NAFLD)的一个新的治疗方法。     

EGF类生长因子来源的新型靶向肽在抗肿瘤药物蛋白中的应用

许多肿瘤细胞表面表皮生长因子受体EGFR都存在过表达现象。考察了牛痘病毒生长因子(VGF)中的EGFR结合域(S3)与人的肝素样表皮生长因子(HB-EGF)来源的肝素结合域(命名为HE)重组后对肿瘤细胞的选择性。通过重组表达带有靶向和穿膜结构域的EGFP-S3-HE和EGFP-S3-HE-TATm两种融合蛋白与正常细胞和肿瘤细胞的共孵育实验来研究其对肿瘤细胞的特异性靶向吸附和穿膜效应。进一步将S3-HE-TATm靶向穿膜序列与苦瓜来源的核糖体失活蛋白MAP30融合,可显著提高MAP30对肿瘤细胞的抑杀作用,但这种抑杀作用却对正常细胞仍保持在较低水平。由此表明S3-HE-TATm是一种新型优异的肿瘤细胞靶向药物运输载体,可用于肿瘤治疗的进一步开发研究。     

The matrix protein CCN1 (CYR61) promotes proliferation, migration and tube formation of endothelial progenitor cells

Neovascularization and re-endothelialization relies on circulating endothelial progenitor cells (EPCs), but their recruitment and angiogenic roles are subjected to regulation by the vascular microenvironment, which remains largely unknown. The present study was designed to investigate the effects of mature ECs and matrix protein CCN1 on the properties of EPCs. In a coculture system, effects of ECs on proliferation, migration and participation in tube-like formation of EPCs were evaluated, and functional assays were employed to identify the exact role of CCN1 in EPCs vitality and function. We demonstrated that ECs, as an indispensable part of the cellular milieu, significantly promoted the proliferation, migration and tube formation activities of EPCs, and more importantly, CCN1 was potentially involved in such effects of ECs. Expression of CCN1 in EPCs was significantly increased by serum, VEGF, ECs-cocultivation and ECs conditioned medium. Moreover, Ad-CCN1-mediated overexpression of CCN1 directly enhanced migration and tube formation of EPCs, whereas silencing of endogenous CCN1 in EPCs inhibits cell functions. Furthermore, CCN1 induced the expressions of chemokines and growth factors, such as MCP-1 and VEGF, suggesting a complex interaction between those proangiogenic factors. Our data suggest that matrix protein CCN1 may play an important role in microenvironment-mediated biological properties of EPCs.     

符号检验法及其在动物生态学研究中的应用

符号检验法是非参数统计法的一种重要方法,在动物生态学的实验数据统计分析领域有一定的实用价值,本文简要介绍这一方法的使用。     

Circ_0075829 facilitates the progression of pancreatic carcinoma by sponging miR‐1287‐5p and activating LAMTOR3 signalling

Pancreatic cancer (PC) is a leading cause of cancer‐related mortality globally. Though increasing evidence has demonstrated that circular RNAs (circRNAs) are linked to the development and progression of cancers, the biological functions of circRNAs in PC remain largely unexplored so far. Based on previous studies, Hsc_circ_0075829 (circ_0075829) was screened out and then further identified in PC clinical specimens and cell lines by real‐time PCR. After the stability tests, a series of in vitro and in vivo functional experiments were performed to investigate the role of circ_0075829 in PC development. Furthermore, fluorescent in situ hybridization (FISH), bioinformatics tools, dual‐luciferase assays and rescue experiments were conducted to clarify the regulatory mechanisms of circ_0075829 in SW1990 and BxPC‐3 cells. Compared with paracancerous tissues, the expression of circ_0075829 was increased in PC tissues, which was positively correlated with the clinical features of PC. Knockdown of circ_0075829 significantly suppressed the proliferative, migratory and invasive rates of SW1990 and BxPC‐3 cells both in vitro and in vivo. Bioinformatics analysis and dual‐luciferase reporter gene assay indicated that circ_0075829 could bind to miR‐1287‐5p. Mechanism research and rescue experiments demonstrated that circ_0075829 could regulate the LAMTOR3/p‐ERK signalling pathway via sponging miR‐1287‐5p in PC cell lines. Our data reveal that the circ_0075829 could facilitate the proliferation and metastasis of PC through circ_0075829/miR‐1287‐5p/LAMTOR3 axis.     

草菇低温胁迫初期应答关键通路的探究

本研究利用表达谱芯片技术解析了低温胁迫初期（0-120min）不同低温处理时间草菇转录组水平的变化。芯片结果分析发现在低温诱导过程中,低温处理20min内变化基因的功能为单加氧酶、氧化还原酶和细胞内的氧化还原。低温处理40min时表达差异基因具有结合RNA的功能。80min的时间段内,基因的功能比较集中于核酸物质和能量的代谢。CYP450的代谢途径在20-40min、60-80min和100-120min低温处理的菌丝体中均有显著性变化,表明这一通路在草菇低温处理过程中表现活跃。基因表达趋势分析发现34个表达差异基因富集到显著表达趋势模型,基因共表达网络分析发现VVO_04066位于网络的核心地位,推测VVO_04066通过提高磷酸肌醇特异性磷脂酶C（PI-PLC）的胞内水平,促进糖蛋白和几丁质的合成,从而完成草菇细胞的低温胁迫应答。     

Persistence of circadian variation in arterial blood pressure in beta1/beta2-adrenergic receptor-deficient mice

The beta-adrenergic pathway has been considered one important effector of circadian variation in arterial pressure. Experiments were performed in beta1/beta2-adrenergic receptor-deficient mice (beta1/beta2ADR-/-) to assess whether this pathway is required for circadian variation in mean arterial pressure (MAP) and to determine the impact of its loss on the response to changes in dietary salt. Twenty-four-hour recordings of MAP, heart rate (HR), and locomotor activity were made in conscious 16- to 17-wk-old mice [wild-type, (WT), n = 7; beta1/beta2ADR-/-, n = 10] by telemetry. Both WT and beta1/beta2ADR-/- mice demonstrated robust circadian variation in MAP and HR, although 24-h mean MAP was 10% lower (102.02 +/- 1.81 vs. 92.11 +/- 2.62 mmHg) in beta1/beta2ADR-/- than WT, HR was 16% lower and day-night differences reduced. Both WT and beta1/beta2ADR-/- mice adapted to changed salt intake without changed MAP. However, the beta1/beta2ADR-/- mice demonstrated a striking reduction in locomotor activity in light and dark phases of the day. In WT mice, MAP was markedly affected by locomotor activity, resulting in bimodal distributions in both light and dark. When MAP was analyzed using only intervals without locomotor activity, bimodality and circadian differences were reduced, and there was no significant difference between the two genotypes. The results indicate that there is no direct effect or role for the beta-adrenergic system in circadian variation of arterial pressure in mice, aside from the indirect consequences of altered locomotor activity. Our results also confirm that locomotor activity contributes strongly to circadian variation in blood pressure in mice.     

CCR6, the Sole Receptor for the Chemokine CCL20, Promotes Spontaneous Intestinal Tumorigenesis

Interactions between the inflammatory chemokine CCL20 and its receptor CCR6 have been associated with colorectal cancer growth and metastasis, however, a causal role for CCL20 signaling through CCR6 in promoting intestinal carcinogenesis has not been demonstrated in vivo. In this study, we aimed to determine the role of CCL20-CCR6 interactions in spontaneous intestinal tumorigenesis. CCR6-deficient mice were crossed with mice heterozygous for a mutation in the adenomatous polyposis coli (APC) gene (APC^MIN/+ mice) to generate APC^MIN/+ mice with CCR6 knocked out (CCR6KO-APC^MIN/+ mice). CCR6KO-APC^MIN/+ mice had diminished spontaneous intestinal tumorigenesis. CCR6KO-APC^MIN/+ also had normal sized spleens as compared to the enlarged spleens found in APC^MIN/+ mice. Decreased macrophage infiltration into intestinal adenomas and non-tumor epithelium was observed in CCR6KO-APC^MIN/+ as compared to APC^MIN/+ mice. CCL20 signaling through CCR6 caused increased production of CCL20 by colorectal cancer cell lines. Furthermore, CCL20 had a direct mitogenic effect on colorectal cancer cells. Thus, interactions between CCL20 and CCR6 promote intestinal carcinogenesis. Our results suggest that the intestinal tumorigenesis driven by CCL20-CCR6 interactions may be driven by macrophage recruitment into the intestine as well as proliferation of neoplastic epithelial cells. This interaction could be targeted for the treatment or prevention of malignancy.