The effect of Polbax extract on lipofuscin accumulation in cultured neonatal rat cardiac myocytes

Polbax, a water-soluble extract of fresh pollen grains and pistils, was tested for its ability to influence the accumulation of lipofuscin (age pigment) in cultured neonatal rat cardiac myocytes. Exposure for 3 weeks to Polbax at concentrations of 0.1, 1.0 or 10 mg/L decreased lipofuscin accumulation morphometrically assayed using laser scanning microscopy images (green excitation light) of formaldehyde-fixed cells, by 24%, 41% or 43%, respectively. Based on the knowledge that oxidative stress and iron-catalysed peroxidation play an important role in lipofuscinogenesis, we suggest that Polbax may slow lipofuscin formation due to antioxidant activities, perhaps involving intralysosomal dismutation of superoxide produced by autophagocytosed mitochondria and/or iron-chelation.     

阿托伐他汀对压力负荷增加引起大鼠心肌肥厚的影响

 目的　观察他汀类药物阿托伐他汀对心肌肥厚大鼠心肌及心肌炎性细胞因子的影响 ,探讨该类药物影响心肌肥厚可能涉及的作用机制。方法　用RT-PCR法和免疫组化法检测心肌细胞因子白细胞介素-1β(interleukin-1β,IL-1β) ,心调理素-1(car diotropin-1,CT-1)的表达,并观察心脏的病理学改变。结果　正常大鼠心肌无炎性细胞因子表达 ,压力负荷增加引起大鼠左心室心肌肥厚时 ,心肌炎性细胞因子IL-1β,CT-1的mRNA和蛋白质表达增加 ,阿托伐他汀可以降低左心室肥厚大鼠心肌IL-1β,CT-1的mRNA和蛋白质的表达 ,并使心脏重/体重值 ,左心室壁平均厚度 ,心肌细胞平均直径均明显降低。结论　阿托伐他汀可能通过发挥抗炎作用抑制压力负荷增加引起的心肌肥厚。     

复方银杏滴丸抑制神经细胞内钙超载的作用及机制分析

 目的观察复方银杏滴丸(CO-GBE)抑制神经细胞内钙超载的作用,并分析其作用环节。方法低糖低氧损伤胎鼠皮层神经细胞模拟脑缺血,双波长荧光分光光度法测定神经细胞内钙含量,观察CO-GBE对细胞内钙超载的抑制作用。并分别采用谷氨酸(Glu),KCl,A23187,乙酰甲胆碱(MCh)和咖啡因(CAF)处理神经细胞,以分析药物的作用环节。结果CO-GBE含药血清可以抑制低糖低氧引起的神经细胞内钙超载。对于由谷氨酸,KC1,A23187及CAF触发的钙超载有抑制作用,但对MCh刺激引起的细胞内钙升高没有影响。结论CO-GBE可能通过多途径抑制缺血缺氧后神经细胞内钙超载,从而桔抗脑缺血损伤。     

茶黄素降低缺血再灌注损伤大鼠心室肌细胞内游离钙浓度的研究

目的研究茶黄素对大鼠心室肌细胞内游离钙浓度([Ca2+]i)的影响并探讨其可能机制。方法在正常台氏液和模拟缺血液中,用激光共聚焦显微镜探测[Ca2+]i,结果用相对荧光强度表示。结果茶黄素(20μmol/L)对正常台氏液中心室肌细胞内[Ca2+]i有影响,但可降低模拟缺血液中心室肌细胞[Ca2+]i的增加。应用钠钙交换体抑制剂NiCl2(100μmol/L)可模拟茶黄素(20μmol/L)在模拟缺血液中的作用。预先应用肌浆网钙泵抑制剂Thapsigar-gin(0.5μmol/L)可大部分取消茶黄素(20μmol/L)在模拟缺血液中的作用。结论茶黄素可通过抑制钠钙交换体转运和增强肌浆网钙泵活动,抑制缺血再灌注损伤中细胞[Ca2+]i的增加。     

黄芪多糖对大鼠心肌缺血再灌注损伤影响的研究

目的探讨黄芪多糖对大鼠心肌缺血再灌注损伤的保护作用。方法健康成年SD雄性大鼠35只,采用冠状动脉结扎的方法建立大鼠心肌缺血模型。分为假手术组(A组),缺血再灌注组(B组),黄芪多糖预处理组(C组),黄芪多糖后处理组(D组),阳性药物对照组(E组),共5组,每组7只。测定心肌坏死标记物、心肌标本梗死面积及重量。结果与缺血再灌注组(B组)比较,黄芪多糖预处理、后处理治疗组大鼠心梗面积明显减少,并且疗效优于腺苷治疗组,差别有统计学意义(P0.05),黄芪多糖预处理组作用明显强于黄芪多糖后处理组(P0.05)。与腺苷治疗组比较,黄芪多糖预处理、后处理治疗组大鼠心梗质量明显减少(P0.05)。与假手术组(A组)相比,缺血再灌注组(B组)CK及TNI的数量显著增加(P0.01)。与缺血再灌注组(B组)相比,C、D、E3组CK及TNI数量显著减少(P0.05)。与腺苷组相比,黄芪多糖预处理、后处理CK及TNI数量减少,差异均有统计学意义(P0.05)。结论黄芪多糖干预组的CK、Tn-Ⅰ水平、心肌梗死区质量及面积明显低于模型对照组,黄芪多糖对大鼠心肌缺血再灌注损伤具有保护作用。     

降脂灵片对压力超负荷所致大鼠心肌肥厚的影响

大鼠腹主动 脉部分狭窄５ ｗ ｋ 后,形成实 验性心肌肥厚模 型,心肌和左心 室重量明 显增加; 心肌过 氧化脂质（ Ｌ Ｐ Ｏ） 含 量显著增加,超氧 化物歧 化酶（ Ｓ Ｏ Ｄ） 活性 下降;心 肌 Ｃａ２ ＋ 和主 动脉 Ｃａ２ ＋ 含量 明显增加,与模 型组相比 Ｐ＜ ０ ．０１ 。给降脂灵片０ ．３５ ｇ／ ｋｇ 和 ０ ．７ｇ／ ｋｇ 后均能降低心肌 和左心室重 量;降低心肌 Ｌ Ｐ Ｏ 含量,增加 Ｓ Ｏ Ｄ 活性;降 低心肌 Ｃａ２ ＋ 和主 动脉 Ｃａ２ ＋ 的含 量。提示降脂灵 片抗心 肌肥厚作用与清 除氧自由基和 钙拮抗有关     

大蒜素对大鼠心室肌细胞L-型钙通道的影响

目的:探讨大蒜素对大鼠心室肌细胞L-型钙通道的作用.方法:用急性酶解法获得大鼠的单个心肌细胞,用标准的全细胞膜片钳技术记录钙通道电流.结果:5、50、250和500μmol/L大蒜素分别抑制钙电流4.4%、26.91%、38.06%、72.90%.250μmol/L大蒜素能使心肌细胞钙电流-电压曲线明显上移,峰电流密度从(7.17±0.65)pA/pF减少至(4.44±0.52)pA/pF(n=15,P<0.05),但激活电位、峰电位和翻转电位无明显改变(P>0.05).大蒜素能使钙电流失活曲线明显左移(P<0.05).大蒜素对钙电流激活曲线、失活再复活曲线和频率依赖性无明显影响(P>0.05).结论:大蒜素呈浓度依赖性地抑制心肌细胞L-型钙通道.     

黄芪多糖对脂多糖诱导大鼠心肌细胞肥大的保护作用

目的研究黄芪多糖对脂多糖(LPS)诱导的大鼠心肌细胞肥大的保护作用。方法新生1～2 d的SD大鼠心肌细胞培养48 h后,设对照组,模型组,黄芪多糖低、中、高质量浓度(1、10、100 mg/L)组。计算机图像分析系统测量细胞体积;RT-PCR法检测心房利钠多肽(ANP)mRNA的表达;ELISA法检测细胞肿瘤坏死因子-α(TNF-α)的量;采用Fluo-3/Am荧光染色剂负载细胞,在激光共聚焦显微镜下测定细胞内钙离子浓度([Ca2+]i)的瞬间变化。结果与对照组相比,LPS 1 mg/L可使心肌细胞体积显著增大,ANP mRNA的表达显著增强,细胞分泌TNF-α蛋白的量显著增加,心肌细胞内[Ca2+]i瞬间峰值增大(P<0.01)。与模型组相比,黄芪多糖1、10、100 mg/L预先给药均可抑制心肌细胞体积增大;细胞产生的TNF-α显著减少,ANP mRNA的表达不同程度地减少(P<0.05),其中10、100 mg/L组这两项指标可恢复到对照组的水平(P>0.05);黄芪多糖10 mg/L可拮抗LPS对正常心肌细胞内[Ca2+]i瞬间变化幅度增大的作用(P<0.01)。结论黄芪多糖对LPS诱导的乳鼠心肌细胞肥大有良好的保护作用,其机制可能与抑制TNF-α的产生、降低[Ca2+]i有关。     

葛根素对大鼠心肌细胞L型钙离子通道的影响

目的 :观察葛根素对大鼠L型钙离子通道的作用。方法 :恒流Langendorff灌流 ,I型胶原酶解分离 ,全细胞膜片钳技术记录离子电流。结果 :2.4 mmol·L^-1葛根素可以抑制单个大鼠心室肌细胞L型钙离子通道电流 ,且成时间依赖性 ;葛根素可以促进L型钙通道电流 电压 (I-V)曲线的上移。结论 :葛根素可以抑制大鼠心室肌细胞的L型钙离子通道电流 ,并提示葛根素的抗心肌缺血和抗心律失常作用可能与抑制L型钙离子通道电流有关。     

非诺贝特和吡格列酮对心肌细胞肿瘤坏死因子-α表达的影响及机制初探

 目的 观察过氧化体增殖物激活型受体(peroxisome proliferator-activated receptors,PPARs)激活剂——非诺贝特和吡格列酮对新生大鼠心肌细胞肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)表达水平的影响,探讨可能涉及的机制。方法 体外原代培养新生Wistar大鼠心肌细胞,分别给予不同浓度的非诺贝特(PPARα激活剂)或吡格列酮(PPARγ激活剂)刺激,并辅加脂多糖诱导TNF-α表达。采用半定量RT-PCR法检测TNF-αmNNA的表达,ELISA法检测TNF-α的蛋白水平。心肌细胞瞬时转染TNF-α启动子控制的报告基因载体,测定CAT相对活性以反映TNF-α基因的转录活性。结果 与对照组相比,非诺贝特组和吡格列酮组的TNF-αmRNA及蛋白表达水平均明显降低,且呈剂量依赖性。心肌细胞瞬时转染全长TNF-α启动子控制的报告基因质粒(-721/+17),非诺贝特或吡格列酮可降低脂多糖诱导的CAT相对活性,而转染核因子κB(NF-κB)结合位点缺失的TNF-α启动子控制的报告基因质粒(-182/+17),非诺贝特、吡格列酮或脂多糖刺激均未能改变心肌细胞的CAT相对活性。结论 非诺贝特和吡格列酮可显著抑制新生大鼠心肌细胞中脂多糖诱导的TNF-α表达,具有抗炎作用,其机制可能部分通过抑制NF-κ信息通路发挥作用。     

穿心草山酮对心肌细胞缺氧—再给氧损伤的保护作用

以Ｌａａｒｓｅ‘ｓ方法建立心肌细胞缺氧－再给氧模型,缺糖缺氧６０ｍｉｎ,再给氧３０ｍｉｎ,结果发现心释放ＬＤＨ含量显著增加,细胞膜流动性下降,再给氧组上述各指标改变加剧。山酮能明显提高心肌细胞的成活率,减少乳酸脱氢酶的释放,增加细胞膜流动性,减少心肌细胞膜的损伤。证明有明显抗心肌细胞缺氧－再给氧损伤作用。     

乌头碱、新乌头碱及次乌头碱对心肌细胞钙释放的影响

目的：探讨乌头碱、新乌头碱、次乌头碱对心肌细胞钙释放的影响。方法分离的成年Sprague-Dawley大鼠左心室心肌细胞分别使用0.3、1、3μmol/L乌头碱、新乌头碱、次乌头碱溶液灌流12 min,灌流后4、8、12 min时检测自发性钙释放(SCR)诱发率以及舒张末期钙浓度(F0)、钙瞬变幅度(ΔF)的变化。检测灌流0.3μmol/L乌头碱、新乌头碱、次乌头碱溶液后12 min,心肌细胞发挥正性肌力作用时钙瞬变和收缩功能动力学指标的变化。结果乌头碱、新乌头碱、次乌头碱均可诱发SCR,0.3μmol/L时新乌头碱SCR诱发率最高,3μmol/L时乌头碱SCR诱发率最高。与对照组比较,给药后12 min,3μmol/L乌头碱、新乌头碱、次乌头碱均可增加 F0[(1.459±0.379)、(1.585±0.493)、(1.213±0.254)比(1.079±0.108)]、ΔF[(1.615±0.455)、(2.210±0.756)、(1.528±0.422)比(1.036±0.125)],差异有统计学意义(P均＜0.05);且新乌头碱ΔF高于乌头碱和次乌头碱(P均＜0.05)。与对照组比较,0.3μmol/L乌头碱、新乌头碱、次乌头碱均可增加ΔF[(0.409±0.127)、(0.423±0.107)、(0.414±0.118)比(0.260±0.065);P＜0.05或P＜0.01]、收缩幅度[(5.464±2.239)%、(7.449±2.548)%、(5.524±1.645)%比(3.428±0.911)%;P＜0.05或 P＜0.01],延长钙瞬变达峰时间[(0.041±0.016)s、(0.039±0.009)s、(0.038±0.011)s 比(0.032±0.007)s;P＜0.05或P＜0.01];与乌头碱组比较,新乌头碱和次乌头碱可降低钙瞬变消除时间常数[(0.301±0.054)s、(0.324±0.064)s 比(0.361±0.076)s;P＜0.05或P＜0.01],缩短舒张期收缩恢复至50%时的时间[(0.124±0.035)s、(0.126±0.040)s 比(0.157±0.056)s;P＜0.05或 P＜0.01]。结论乌头碱、新乌头碱、次乌头碱的正性肌力作用与毒性效应同时存在,表明心肌细胞内钙浓度升高是产生正性肌力作用的有利因素,也是诱发SCR的危险因素。     

Protective effect of astragalosides on myocardial injury by isoproterenol in SD rats

We have extracted and roughly purified astragalosides (AS) from Astragalus membranaceus, a natural herb used as a traditional Chinese medicine, regarded to have pharmacodynamic benefits of protecting injured myocardium. We hypothesized that the astragalosides might exert beneficial effect in myocardial lesion by preserving both energy metabolism and Ca(2+) homeostasis. Sprague-Dauley (SD) rats were injected with isoproterenol (ISO) subcutaneous (s.c.) at a dose of 5 mg/kg/day consecutively for two days as models and were treated with astragalosides and trimetazidine intraperitoneally (i.p.) respectively, at a dose of 5 mg/kg/day one day prior to isoproterenol for 8 days. The histological changes were alleviated in isoproterenol-injected SD rats treated with astragalosides. Compared with isoproterenol-injected rats, the concentration of myocardial intracellular [Ca(2+)]i was decreased, L-type Ca(2+) current density and sarcoplasmic reticulum (SR) Ca(2+) load were recovered, the concentration of myocardial ATP was increased and phosphocreatine (PCr) was decreased in rats treated with astragalosides. In conclusion, the efficacious treatment of astragalosides for myocardial injury might be through regulating intracellular Ca(2+) homeostasis and energy metabolism.     

Effects and mechanisms of crude astragalosides fraction on liver fibrosis in rats

Astragalosides is the major active constituent of Radix Astragali. The present study was carried out to investigate the effect of crude astragalosides fraction (CAF) on rats liver fibrosis and its possible mechanisms. Hepatic fibrosis was induced by subcutaneous injection with 50% CCl(4) in Sprague-Dawley rats. The amount of CCl(4) administered was 1 mg kg(-1). The alanine aminotransferase (ALT), aspartate aminotransferase (AST) levels in plasma and hydroxyproline (Hyp), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) contents in liver tissue were assayed by spectrophotometry. The hyaluronic acid (HA) and procollagen III (PC III) were assessed by radioimmunoassay. Tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta1 (TGF-beta1) levels in culture supernatants of Kupffer cells (KCs) were determined with ELISA. Liver samples collected after 8 weeks of CCl(4) treatment were stained with hematoxylin-eosin (HE) and massion, and scored. Intragastric administration of CAF (10, 20 and 40 mg kg(-1)) significantly decreased indices of liver and spleen, the serum transaminase activities, HA and PC III levels, and Hyp and MDA contents in liver tissue in rats of hepatic fibrosis. Decreased SOD and GSH-px levels were reversed after administration of CAF. Histopathological scores showed CAF had inhibitory effect on the progression of hepatic fibrosis. In the in vitro experiments, CAF significantly reduced TNF-alpha and TGF-beta1 levels in culture supernatants of KCs. The results showed CAF significantly inhibited the progression of hepatic fibrosis induced by CCl(4), and the inhibitory effect of CAF on hepatic fibrosis might be associated with its ability to scavenge free radical and inhibit the production of TNF-alpha and TGF-beta1 from activated KCs.     

西红花酸对缺糖缺氧心肌细胞损伤的保护作用

目的　观察西红花酸 (crocetin)对缺糖缺氧心肌细胞损伤的保护作用。方法　采用氰化钠和灌封高纯氮气两种缺氧方法和低糖培养 ,造成心肌细胞缺糖缺氧损伤 ,测定其细胞培养液中乳酸脱氢酶 (L DH )、肌酸激酶(CK)的活力及心肌细胞中脂质过氧化产物丙二醛 (MDA)的含量来观察西红花酸对心肌细胞的保护作用。结果1× 10 - 6 ,1× 10 - 7mol/ L 西红花酸能显著降低缺糖缺氧心肌细胞 MDA的含量以及 L DH、CK的活性。结论　西红花酸对缺糖缺氧损伤的心肌细胞具有显著的保护作用。     

灵芝多糖对小鼠腹腔巨噬细胞胞浆游离Ca2+浓度的影响

 目的:探讨灵芝多糖(GLP)对免疫细胞信号转导过程的影响?方法:采用激光扫描共聚焦显微镜(LSCM)技术,动态监测GLP均一体组分GLB₇对小鼠腹腔巨噬细胞(MΦ)胞浆游离Ca²⁺浓度([Ca²⁺]i)的影响?结果:GLB₇(20μg·ml^-1)引起小鼠腹腔MΦ中[Ca²⁺]i明显升高,升高值为(248±18)%(n=6);GLB₇引起小鼠腹腔MΦ外钙内流及MΦ内IP₃敏感和IP₃非敏感钙池释放Ca²⁺,[Ca²⁺]i升高值分别为(76±10)%,(58±10)%,(41±8)%(n=6);GLB₇对MΦ[Ca²⁺]i的影响与K⁺通道及其引起的膜电位变化无关?结论:MΦ是灵芝多糖作用的靶细胞;GLB₇引起MΦ中[Ca²⁺]i快速升高,可能是灵芝多糖产生作用的重要途径?     

枳实薤白桂枝汤通过保护缝隙连接干预心肌缺血再灌注钙超载的研究

目的:探讨枳实薤白桂枝汤能否通过保护细胞缝隙连接干预钙超载,进而减轻心肌细胞缺血再灌注损伤。方法:大鼠随机分假手术组、模型组、枳实薤白桂枝汤2.30g/kg、4.59g/kg、9.18g/kg组,给药14天后结扎冠状动脉前降支造模,观察各组心电图、心肌酶(CK-MB、LDH、ALT、AST)、病理及超微结构的改变,并以免疫组织化学染色法观察闰盘重构程度及缝隙连接蛋白43(connexin43,Cx43)表达,Western blot法检测Cx43、磷酸化缝隙连接蛋白43(phospho-connexin43,p-Cx43)、蛋白激酶C(protein kinase C,PKC)及钠钙交换体1(Na~+/Ca~(2+) exchanger 1,NCX1)的表达。结果:与模型组相比,枳实薤白桂枝汤组心电图及心肌酶改变明显减轻、细胞超微结构改变及闰盘重构程度也明显减轻,Cx43、PKC、p-Cx43的表达增加, NCX1的表达降低。结论:枳实薤白桂枝汤在发生心肌缺血再灌注损伤时能有效保护细胞缝隙连接,减少NCX1的表达,进而干预心肌细胞钙超载的过程,产生心肌保护作用,且4.59g/kg、9.18g/kg剂量组效果较为明显。     

粉防己碱对培养乳鼠心肌细胞内游离钙的影响

 目的：观察粉防己碱（Tet)对培养大鼠心肌细胞内游离钙（[Ca2+]i)的影响。方法：运用Ca2+指示剂Fura-2作 为细胞内钙离子的荧光探针，利用AR-CM-MIC阳离子測定系统，检測培养乳鼠心肌细胞内游离钙的浓度 [Ca2+]i。结果：在细胞外液钙浓度为1.8mmol/L时，心肌细胞静息[Ca2+]i为80.3士6.9mmol/L。在细胞外液钙浓度为1.8-5.4mmol/L时，粉防己碱（Tet)对细胞静息[Ca2+]i无明显影响。Tet1-100Mmol/L剂量依賴的抑 制高钾和H202引起的[Ca2+]i的升高，Tetl0μmol/L能对抗去甲肾上腺素引起的[Ca2+]i,升高。对搏动细胞，Tet 能抑制细胞外高钙引起的收缩期[Ca2+]i瞬间的变化，减慢搏动頻率。结论:Tet对高K+、去甲肾上腺素、H202及高 钙引起的[Ca2+]i,增高的抑制作用可能是其抗心肌缺血机理之一。     

Cardioprotective effects of hydroxysafflor yellow A on diabetic cardiac insufficiency attributed to up-regulation of the expression of intracellular calcium handling proteins of sarcoplasmic reticulum in rats

Depressed sarcoplasmic reticulum (SR) Ca(2+)-ATPase (SERCA2a) and Ca(2+)-release channels (ryanodine receptor RyR2) are involved in diabetic cardiomyopathy, however, the implication of intracellular calcium handling proteins in SR is undefined. It was hypothesized that the down-regulation of the intracellular calcium handling proteins of SR is closely related to an up-regulated endothelin (ET) system. Hydroxysafflor yellow A (HSYA) is expected to ameliorate cardiac insufficiency which is mediated by the depressed intracellular calcium handling system in diabetic rat heart. Diabetes was produced in male rats 8 weeks after an injection of streptozotocin (60 mg/kg i.p.) and HSYA was administered (100 mg/kg) by gavage in the last 4 weeks. Hemodynamic and echocardiographic changes, cardiac calcium handling proteins, serum biochemistry, ET system and redox were measured. The compromised cardiac function in diabetic rats was accompanied by a significant down-regulation of the expression of RyR2, FKBP12.6 as well as SERCA2a and PLB. These were closely linked with oxidative stress, an increased ET-1 and up-regulation of ECE, PropreET-1 and iNOS mRNA in diabetic cardiomyopathy. After a 4 week treatment with HSYA, all abnormalities were reversed significantly. In conclusion, diabetic cardiomyopathy was correlated with an abnormal expression of calcium handing proteins in SR and an activated ET-ROS (reactive oxygen species) system in the diabetic affected myocardium. HSYA significantly improved the cardiac function and down-regulated the ET system and ROS pathway, resulting in a reversal of the abnormalities of expression of calcium handing proteins and the cardiac performance in diabetic cardiomyopathy.     

蜈蚣提取液对大鼠心脏血流动力学的作用研究

目的　研究蜈蚣提取液对大鼠心脏血流动力学的影响。方法　将动物分为假手术组、模型组与蜈蚣组 3组 ,前 2组腹腔注射 0 .9%氯化钠注射液 ,蜈蚣组腹腔注射蜈蚣提取液 ,后 2组采用结扎法复制在体大鼠急性心肌缺血再灌注损伤模型 ,每只大鼠均于药后 4 5、6 0min时运用MPA -Ⅳ型多道生物信号分析系统采样左心室功能指标 ,并进行组间对比。结果　蜈蚣组左室收缩压、左心室内压最大上升率、左心室内压最大下降率较模型组明显增高 (P <0 .0 5 ) ,左室舒张末期压有所下降 ,心率有所加快 ,但差异无显著性(P >0 .0 5 ) 。结论　蜈蚣提取液对在体大鼠心脏血流动力学有明显改善作用 ,对急性心肌缺血再灌注损伤的左心功能有明显保护作用