沉默钙非依赖型磷脂酶A2β基因对间歇性高糖诱导胰岛微血管内皮细胞凋亡的影响

目的 通过小分子干扰（siRNA）技术沉默大鼠胰岛微血管内皮细胞（IMECs）的钙非依赖型磷脂酶A2（iPLA2）基因,研究不同葡萄糖浓度对IMECs iPLA2表达的影响及其与细胞凋亡之间的关系.方法 通过分离纯化大鼠胰岛,获取IMECs细胞,采用随机数余数分组法将其分为正常糖组（5 mmol/L）、恒定高糖组（28 mmol/L）及间歇高糖组（每24小时轮换培养于5mmol/L或28 mmol/L葡萄糖）;通过实时定量聚合酶链反应（RT-PCR）检测葡萄糖浓度分别为恒定的5 mmol/L、28 mmol/L以及每24小时轮换的5 mmol/L或28 mmol/L培养条件下的IMECs iPLA2的基因表达;合成iPLA2的RNA干扰序列并转染至IMECs中,通过RT-PCR验证其是否转染成功;采用细胞DNA片段化检测和膜联蛋白V-异硫氰酸荧光素/碘化丙啶（Annexin V/PI）流式细胞仪检测不同葡萄糖浓度条件下IMECs的凋亡.组间两两比较采用LSD检验,凋亡率采用随机区组设计的两因素ANOVA分析.结果 RT-PCR检测显示各组细胞iPLA2基因表达逐渐减弱,依次为1.90±0.23、0.90±0.05及0.23±0.03,且各组间差异有统计学意义（P＜0.05）.成功合成并转染iPLA2 siRNA后,IMECs间歇性葡萄糖培养组较正常糖组及恒定高糖组DNA片段化更为明显,间歇高糖组流式细胞凋亡率较正常糖组升高,差异有统计学意义（44.9±2.7比3.1±1.0,P＜0.05）.结论 间歇性高糖环境可抑制IMECsiPIA2基因表达,且通过小分子干扰技术抑制iPLA2基因表达能够促进细胞的凋亡,提示iPLA2表达减弱可能参与了间歇性高糖诱导的IMECs凋亡过程.     

阿托伐他汀对椎基底动脉供血不足患者Lp-PLA2和hs-CRP的影响

目的观察阿托伐他汀对椎基底动脉（BA）供血不足患者脂蛋白相关磷脂酶-A2（Lp-PLA2）及超敏C反应蛋白（hs-CRP）的影响。方法选择我科收治的78例BA供血不足患者,随机分为治疗组及对照组,每组39例。对照组给予常规抗凝、活血、改善循环治疗,治疗组在此基础上加用阿托伐他汀（20 mg,1次/d）。在治疗前及治疗后7 d分别查2组血清Lp-PLA2及hs-CRP,经颅多普勒（TCD）评估治疗前后BA收缩期峰流速（Vp）。结果2组治疗前血清Lp-PLA2及hs-CRP水平比较,差异无统计学意义（P〉0.05）,治疗7 d后2组血清Lp-PLA2及hs-CRP水平均较治疗前明显降低（P〈0.05）,且治疗组降低较对照组更为明显,差异有统计学意义（P〈0.05）。治疗组椎动脉（VA）及BA的Vp改善优于对照组,差异有统计学意义（P〈0.05）。结论在改善循环基础上联合阿托伐他汀能改善BA、Vp,其机制可能是通过降低血清Lp-PLA2及hs-CRP水平,从而改善患者血液黏度、增加脑血供水平。     

血清Lp-PLA2 GGT与冠心病及冠状动脉病变严重程度的相关性分析

目的分析血清脂蛋白相关磷脂酶A2(Lp-PLA2)、γ-谷氨酰转移酶(GGT)与冠心病(CHD)及冠状动脉病变严重程度的相关性。方法选择2018-06~2019-06于郑州大学第二附属医院心内科首次就诊的170例疑似CHD患者的临床资料,根据冠状动脉造影检查结果分为CHD组(103例)和非CHD组(67例)。检测患者血清Lp-PLA2、GGT水平,分析血清Lp-PLA2、GGT与CHD及冠状动脉病变严重程度的关系。结果CHD组Lp-PLA2、GGT、甘油三酯(TG)、低密度脂蛋白(LDL)、Gensin积分水平以及合并高血压、糖尿病人数比例显著高于非CHD组(P<0.05),而高密度脂蛋白(HDL)水平显著低于非CHD组(P<0.05)。Spearman相关分析结果显示,CHD患者血清Lp-PLA2、GGT水平与冠状动脉病变支数呈正相关(rs=0.681,P=0.000;rs=0.603,P=0.000)。Pearson相关分析结果显示,CHD患者血清Lp-PLA2、GGT水平与Gensin积分呈正相关(r=0.799,P=0.000;r=0.621,P=0.000)。多因素logistic分析结果显示,较高水平的Lp-PLA₂、GGT和LDL,以及合并高血压是促进CHD发生的危险因素(P<0.05);而较高水平的HDL是抑制CHD发生的保护因素(P<0.05)。结论较高水平的血清Lp-PLA2、GGT是促进CHD发生的危险因素,可较好地反映冠状动脉病变严重程度,可作为评估CHD发生、进展的可靠指标。     

瑞舒伐他汀和阿托伐他汀对高胆固醇血症患者血浆脂蛋白相关性磷脂酶A2的影响

目的 比较瑞舒伐他汀和阿托伐他汀对高胆固醇血症惠者血浆脂蛋白相关性磷脂酶A2(LpPLA2)活性的影响.方法 本试验为随机、双盲研究.在4周治疗性生活方式改善后,符合入选标准的高胆固醇血症患者随机分入瑞舒伐他汀5 mg组(瑞舒伐他汀5 mg/d)、瑞舒伐他汀10 mg组(瑞舒伐他汀10 mg/d)和阿托伐他汀10 mg组(阿托伐他汀10 mg/d),治疗8周.药物治疗前和治疗8周后测定血清总胆固醇、血清甘油三酯、血清低密度脂蛋白胆固醇、血清高密度脂蛋白胆固醇水平以及血浆Lp-PLA2活性.结果 60例高胆固醇血症患者入选.治疗前各组血脂参数和血浆Lp-PLA2活性相似.治疗8周后,瑞舒伐他汀5 mg组、瑞舒伐他汀10 mg组和阿托伐他汀10 mg组血清低密度脂蛋白胆固醇(LDL-C)水平分别降低35%、41%和36%,血浆Lp-PLA2活性降低幅度分别为15%、17%和15%.血浆Lp-PLA2活性和血清LDL-C水平相关(r=0.507,P=0.00).结论 高胆固醇血症患者瑞舒伐他汀和阿托伐他汀治疗8周后,血浆Lp-PLA2活性均显著下降.血浆Lp-PLA2活性和血清LDL-C水平相关.     

瑞舒伐他汀对兔动脉粥样硬化的影响

目的观察瑞舒伐他汀对兔动脉粥样硬化的影响。方法新西兰大白兔30只,随机分为对照组、模型组与治疗组,每组10只。对照组以标准基础饲料喂养。模型组和治疗组以高脂饲料喂养4周后,行颈动脉内膜球囊损伤术,分别继续给予高脂饲料及高脂饲料加瑞舒伐他汀喂养6周。于4、10周末取血测定血脂及脂蛋白相关磷脂酶A2（Lp-PLA2）的水平。于10周末将兔处死时,取颈动脉标本行病理切片,免疫组织化学方法检测Lp-PLA2的表达。结果与对照组相比,模型组及治疗组血脂及Lp-PLA2水平均明显升高（t=2.11~218.85,P〈0.05）;治疗组血脂及Lp-PLA2水平均明显低于模型组（t=5.37~228.83,P〈0.05）。对照组未见动脉粥样硬化病变及Lp-PLA2表达,治疗组动脉粥样硬化斑块中Lp-PLA2的表达也明显低于模型组（t=4.71,P〈0.05）。结论瑞舒伐他汀可降低血脂及Lp-PLA2的水平,可能具有抗炎及抑制动脉粥样硬化进展的作用。     

脂蛋白相关磷脂酶A2与冠心病的相关性研究进展

血浆脂蛋白相关磷脂酶A2(LP-PLA2)由成熟的巨噬细胞和淋巴细胞合成和分泌,又称血小板活化因子乙酰水解酶(PAF-AH),在血浆中主要与低密度脂蛋白结合.近年来,越来越多研究表明在冠心病的发病机制及预防性治疗上,LP-PLA2是一个新的有待研究的因子,其在循环中的含量和活性与冠状动脉事件风险存在正相关,可能成为冠心病治疗的新靶点.     

急性冠脉综合征并发2型糖尿病患者血清脂蛋白磷脂酶A2浓度及其与冠状动脉病变程度的相关性

目的探讨急性冠状动脉综合征(acute coronary syndrome,ACS)并发2型糖尿病(type 2 diabetes mellitus,T2DM)患者血清脂蛋白磷脂酶A2(lipoprotein phospholipase A2,Lp-PLA2)浓度及其与冠状动脉病变程度的相关性。方法选择佛山市第一人民医院禅城医院2017年8月至2018年10月106例ACS患者为研究对象,其中53例无并发糖尿病为对照组,53例并发T2DM为观察组,另选择同期健康体检人群60名为正常组。检测3组受试者血清Lp-PLA2浓度及肱动脉血流介导的血管内皮舒张功能(flow mediated dilation,FMD);计算3组受试者冠状动脉病变Gensini积分;超声检测3组受试者冠状动脉病变程度。结果观察组血清Lp-PLA2浓度、冠状动脉病变Gensini积分明显高于对照组和正常组,差异有统计学意义(P<0.05)。观察组FMD明显低于对照组和正常组,差异有统计学意义(P<0.05)。观察组超声检测参数明显比对照组和正常组差,差异有统计学意义(P<0.05)。与观察组单支或双支冠状动脉病变血管患者比较,冠状动脉病变3支及以上患者血清Lp-PLA2浓度明显上升,差异有统计学意义[(510.64±46.93)ng/mL vs.(443.36±44.58)ng/mL,P<0.05;vs.(510.64±46.93)ng/mL vs.(397.25±38.42)ng/mL,P<0.05]。观察组血清Lp-PLA2浓度与FMD呈负相关,与冠状动脉病变Gensini积分呈正相关。结论ACS并发T2DM患者血清Lp-PLA2浓度增高并与冠状动脉病变程度有关。     

Upregulated phospholipase D2 expression and activity is related to the metastatic properties of melanoma

The incidence rates of melanoma have increased steadily in recent decades and nearly 25% of the patients diagnosed with early-stage melanoma will eventually develop metastasis, for which there is currently no fully effective treatment. The link between phospholipases and tumors has been studied extensively, particularly in breast and colon cancers. With the aim of finding new biomarkers and therapeutic options for melanoma, the expression of different phospholipases was assessed in 17 distinct cell lines in the present study, demonstrating that phospholipase D2 (PLD2) is upregulated in metastatic melanoma as compared to normal skin melanocytes. These results were corroborated by immunofluorescence and lipase activity assays. Upregulation of PLD2 expression and increased lipase activity were observed in metastatic melanoma relative to normal skin melanocytes. So far, the implication of PLD2 activity in melanoma malignancies has remained elusive. To the best of our knowledge, the present study was the first to demonstrate that the overexpression of PLD2 enhances lipase activity, and its effect to increase the proliferation, migration and invasion capacity of melanoma cells was assessed with XTT and Transwell assays. In addition, silencing of PLD2 in melanoma cells reduced the metastatic potential of these cells. The present study provided evidence that PLD2 is involved in melanoma malignancy and in particular, in its metastatic potential, and established a basis for future studies evaluating PLD2 blockade as a therapeutic strategy to manage this condition.     

Cloning,functional expression,and characterization of an edema-producing Asp-49 phospholipase A2 from Trimeresurus mucrosquamatus

The snake-bite of Trimeresurus mucrosquamatus can cause severe edema and result in complications. Snake venom phospholipase A₂s are the major components responsible for causing edema. Therefore, understanding the edema-producing mechanism induced by the venom of T. mucrosquamatus can be important in treating the edema. In order to study the edema-producing effect, a venom Asp-49 phospholipase A₂ (TMV-D49-PLA₂) was cloned, sequenced, and functionally expressed in Escherichia coli. This expressed venom protein demonstrated specific phospholipase activities both in the digestion of lecithin in vitro and in inducing edema in rats in vivo. Therefore, the cloning and functional expression of the recombinant edema-producing protein are critical steps and should allow further characterization of the functional motifs responsible for both the edema-inducing activity and the development of therapeutic antiserum against the edema effect of the snake venom proteins.     

Mechanisms of tumour invasion and metastasis: emerging targets for therapy

The progression of a tumour from one of benign and delimited growth to one that is invasive and metastatic is the major cause of poor clinical outcome in cancer patients. The invasion and metastasis of tumours is a highly complex and multistep process that requires a tumour cell to modulate its ability to adhere, degrade the surrounding extracellular matrix, migrate, proliferate at a secondary site and stimulate angiogenesis. Knowledge of the process has greatly increased and this has resulted in the identification of a number of molecules that are fundamental to the process. The involvement of these molecules has been shown to relate not only to the survival and proliferation of the tumour cell but, also to the processes of tumour cell adhesion, migration, and the tumour cells ability to degrade and escape the primary site as well as play a role in angiogenesis. These molecules may provide important therapeutic targets that represent the ability to target specific steps in the process of invasion and metastasis and provide additional therapies. The review focuses on representative key targets in each of these processes and summarises the state of play in each case.