锌对缺血后适应预防糖尿病大鼠心肌缺血再灌注损伤的影响

目的探讨锌对离体糖尿病(DM)大鼠缺血后适应预防心肌缺血再灌注损伤作用的影响。方法高脂饮食联合链脲佐菌素(STZ)诱导建成2型DM(T2DM)大鼠模型,将40只雄性Wistar大鼠随机平均分为正常大鼠缺血再灌注组(A组:N+I/R),正常大鼠缺血后适应组(B组),DM大鼠后适应组(C组),锌干预DM大鼠后适应组(D组)。四组均采用离体大鼠心脏灌流模型方法,全心停灌30 min,复灌60 min,制成心肌缺血再灌注模型,对B、C、D三组在再灌注初始时,均先给予再灌注10 s,全心停灌10 s,共6次循环的缺血后适应干预。测定左室收缩压(LVSP)和再灌30 min冠状动脉流出液中乳酸脱氢酶(LDH)和肌酸激酶(CK)的含量。分离左室心肌并测定心肌梗死面积,对心肌进行免疫组织化学染色测定磷酸化蛋白激酶B(P-Akt)和磷酸化糖原合成酶激酶(GSK-3β)的表达。结果 D组与C组相比,锌干预的离体DM大鼠心脏缺血后适应可显著改善再灌注后LVSP以及左心室内压最大上升速率(+d P/dtmax)等血流动力学指标,并显著减少了再灌注后LDH与CK的释放量;同时缺血后适应干预减少了心肌梗死的面积,P-Akt及P-GSK-3β的表达增加。C组与A组相比,对DM大鼠给予缺血后适应处理后,其血流动力学无明显改善,且心肌酶释放量未减低,同时也没有显著减少心梗面积,P-Akt,P-GSK-3β的表达减少。结论锌干预的离体大鼠心脏恢复或增强了缺血后适应对DM大鼠心肌再灌注损伤的保护作用,其机制与锌使DM大鼠心肌细胞内P-Akt及P-GSK-3β增强,进而使缺血后心肌梗死面积减小和心肌酶释放量减少有关。     

糖尿病对离体大鼠缺血后适应心肌保护作用的影响

目的探讨糖尿病对离体大鼠缺血后适应心肌保护作用的影响。方法诱导2型糖尿病大鼠模型,采用Langendorff离体心脏灌流法,全心停灌30min,复灌60min,制成心肌缺血模型;全心停灌30min后,给予再灌注10s、停灌10s6次循环,然后再灌注至60min,制备缺血后适应模型。测定血流动力学指标和复灌20min冠状动脉流出液中乳酸脱氢酶(LDH)、肌酸激酶(CK)的含量。实验结束分离出左心室心肌并横切成5片,并测定心肌梗死面积。结果糖尿病大鼠缺血后适应血流动力学无明显改善,心肌酶释放量未减低,心肌梗死面积未显著减少(50.1%±3.7%比45.7%±4.8%,P0.05)。结论缺血后适应对糖尿病大鼠离体心脏无保护作用。     

大剂量当归预适应抗心肌缺血再灌注后心肌细胞凋亡的机制

目的观察大剂量当归水煎液预适应对缺血再灌注(IR)大鼠心肌细胞凋亡及心肌组织Bcl-2及Bax蛋白表达的影响。方法应用离体灌流大鼠心脏,复制大鼠心肌IR与缺血预适应(IPC)模型,并以不同大剂量当归水煎液灌胃6 w后,取大鼠心脏进行离体灌注,复制当归IPC模型,以TTC法测定心肌梗死面积,以Tunel法检测细胞凋亡,Western印迹法检测Bcl-2及Bax蛋白表达。结果大剂量当归水煎液预适应能有效降低IR大鼠心肌梗死面积,降低心肌细胞的凋亡率,并增加心肌组织Bcl-2的表达而抑制Bax的表达,且呈现明显剂量-效应关系(P0.05,P0.01)。结论大剂量当归水煎液预适应可增加心肌组织Bcl-2的表达而抑制Bax的表达,从而减少IR大鼠心肌细胞的凋亡,对IR大鼠心肌具有明显保护作用。     

缺血后适应心肌线粒体能量代谢研究

目的研究缺血后适应心肌线粒体能量代谢特点。方法以Langendofff离体心脏灌注系统构建缺血后适应大鼠模型，随机分为对照组．再灌注组和后适应组，每组16只。平衡20min后，对照组灌注60min;再灌注组停灌30min，再灌注30min；后适应组停灌30min之后，循环6次再灌注10s，停灌10s，再灌注28min。记录心率和冠状动脉流量。冉灌注末取心肌．用高效液相色谱法测定高能磷酸化合物三磷腺苷、二磷腺苷和一磷腺苷含量；用差速离心法提取心肌线粒体，用氧电极法测定线粒体3态呼吸、4态呼吸和线粒体呼吸控制率。结果与再灌注组比较，后适应组明显提高再灌注末的心率和冠状动脉流量，明显提高心肌内二磷腺苷和一磷腺苷含量，三磷腺苷在各组差异无统计学意义。线粒体3态呼吸和线粒体呼吸控制率改善。结论心肌线粒体能量代谢改善，是缺血后适应心肌保护的可能机制之一。     

心肌缺血再灌注损伤的研究进展

对于急性心肌梗死患者,利用溶栓或早期用经皮冠状动脉介入治疗(PCI)进行有效的心肌再灌注是缩小心肌梗死面积,改善临床转归的有效方法.缺血预适应和缺血后适应不仅对动物的心脏有保护作用,同样对人类心脏也具有保护作用.通过再灌注损伤补救激酶(RISK)途径,阻止线粒体转运通道(PTP)开放等干预再灌注损伤递质的措施,能够明显减轻急性心肌梗死患者心肌缺血再灌注损伤.     

缺血后处理减轻大鼠肥厚心肌缺血再灌注损伤的观察

目的探讨缺血后处理对心肌肥厚大鼠离体心脏缺血再灌注损伤的影响及其信号机制。方法通过腹主动脉结扎建立大鼠心肌肥厚模型,用Landendorff装置建立心肌肥厚大鼠离体心脏缺血再灌注模型。观察缺血后处理对心肌肥厚大鼠离体缺血再灌注心脏左心室收缩压,冠状动脉流量,肌酸磷酸激酶和乳酸脱氢酶释放,心肌梗死范围,心肌组织中蛋白激酶B／Akt（Akt）、糖原合成酶激酶-3β（GSK-3β）磷酸化的影响。结果与缺血再灌注对照组相比,缺血后处理组心脏左心室收缩压、冠状动脉流量显著高,冠状动脉循环流出液中肌酸磷酸激酶、乳酸脱氢酶含量低,心肌梗死范围减小,心肌组织中磷酸化Akt（Ser473）、磷酸化GSK-3β（Set9）水平高,磷脂酰肌醇-3激酶（PI3K）抑制剂渥曼青霉素（wortmannin）能够抑制缺血后处理所致的磷酸化Akt（Ser473）、磷酸化GSK-3β（Set9）水平升高,但只能部分消除缺血后处理的心脏保护效应。结论缺血后处理能够减轻心肌肥厚大鼠离体心脏缺血再灌注损伤,PI3K／Akt／GSK-3信号途径参与介导缺血后处理对离体缺血再灌注肥厚心肌的保护作用。     

转染Livin对糖尿病大鼠心肌缺血再灌注损伤的影响

目的观察转染Livin对糖尿病大鼠心肌缺血再灌注过程中Livin、Caspase-3表达以及心肌细胞凋亡和心肌梗死范围的影响。方法健康SD大鼠80只,应用小剂量多次链脲佐菌素(STZ)注射法建立2型糖尿病大鼠模型,随机选取60只大鼠分为假手术组、缺血再灌注(IR)组、空载体组和Livin组。假手术组不结扎冠状动脉;Livin组开胸心肌内注射表达Livin的逆转录病毒载体,24h后行IR;空载体组开胸注射空载体,24h后行IR。荧光定量PCR测定Caspase-3 mRNA,Livin mRNA表达,用TTC染色法测定梗死范围,TUNEL法测定凋亡心肌细胞。结果①荧光定量PCR检测到糖尿病大鼠心肌细胞有Livin表达,空载体组及IR组Livin表达均不增加;转染Livin后大鼠心肌内Livin表达明显增加(P0.01)。②IR组Caspase-3表达明显增加,显著高于假手术组(P0.01);与IR组相比,Livin组Caspase-3 mRNA表达水平显著降低(P0.01)。③Livin组心肌梗死范围较IR组显著减少(P0.05)。④TUNEL法检测显示糖尿病大鼠IR过程中可见心肌细胞凋亡的发生,IR组较对照组显著增加(P0.05);注射Livin后则细胞凋亡的发生明显减少,与IR组比较差异显著(P0.05)。结论心肌Livin过表达可以抑制糖尿病大鼠心肌Caspase-3表达,抑制IR过程中心肌细胞凋亡的发生,缩小心肌梗死范围。     

中叶素对糖尿病大鼠缺血再灌注心肌细胞凋亡的影响

目的观察中叶素(IMD)对糖尿病大鼠缺血再灌注心肌细胞凋亡的影响,并探讨其可能的作用机制。方法健康雄性SD大鼠74只,给予适应性饲养一周后,随机分为糖尿病组(50只)和非糖尿病组(24只),非糖尿病组给予枸橼酸缓冲液腹腔注射,糖尿病组通过腹腔注射链脲佐菌素建立糖尿病模型。阻断大鼠左冠状动脉前降支制备心肌缺血再灌注损伤模型。非糖尿病组24只大鼠随机分为对照组和缺血再灌注组(NIR组),糖尿病组50只大鼠成功建立糖尿病模型为36只,随后随机分为糖尿病对照组、糖尿病缺血再灌注组(DIR组)、IMD组,每组12只。光镜观察心肌细胞的形态变化,电镜观察心脏超微结构,TUNEL法检测心肌细胞凋亡率,Western blot检测凋亡相关蛋白Caspase-3、Bcl-2和Bax的蛋白表达量。结果光镜下可观察到NIR组、DIR组心肌细胞损伤变化比相应对照组更趋于严重,IMD组心肌细胞变性坏死的程度较糖尿病缺血再灌注组明显减轻。电镜下NIR组和DIR组心肌细胞损伤较相应对照组严重,IMD组心肌组织的超微结构特别是线粒体损伤与DIR组比较明显减轻。NIR组和DIR组心肌细胞凋亡率明显高于相应的对照组(P0.05),IMD组心肌细胞凋亡率则较NIR组明显减少(P0.05)。NIR组和DIR组Caspase-3、Bax和Bcl-2的蛋白表达量均与相应对照组比较差异有统计学意义(P0.05),IMD组心肌组织Caspase-3、Bax和Bcl-2的蛋白表达量与DIR组相比差异也具有统计学意义(P0.05)。结论IMD对糖尿病大鼠心肌缺血再灌注损伤具有保护作用,其保护作用可能与IMD减少心肌细胞凋亡有关。     

2型糖尿病对大鼠心肌缺血再灌注损伤救援激酶信号通路的影响

目的 探讨2型糖尿病(T2DM)对心肌缺血后适应(ischemic postconditioning,IPO )减轻心肌缺血再灌注损伤作用的影响及可能机制.方法　高脂饮食联合STZ诱导制成T2DM大鼠模型,将60只雄性Wistar大鼠随机分为正常大鼠缺血再灌注组(A组)、正常大鼠缺血后适应组(B组)、糖尿病大鼠后适应组(C组).3组均采用离体大鼠心脏Langendorff灌流方法　,全心停灌30 min,复灌60 min,制成心肌缺血再灌注模型.B、C组在再灌注开始前先给予再灌注10 s,全心停灌10 s,共6次循环的IPO.免疫组织化学染色及Western印迹法测定心肌磷酸化Akt,磷酸化糖原合成酶激酶(GSK-3β)的表达.结果 正常离体大鼠心肌IPO干预后磷酸化Akt及GSK-3β的表达增强;而对T2DM大鼠给予IPO处理后磷酸化Akt及GSK-3β的表达无增强,去磷酸化GSK-3β表达增强.结论 IPO对正常大鼠离体心脏缺血再灌注损伤有明确的保护作用,而对T2DM大鼠心肌缺血再灌注损伤无保护作用;其机制可能与糖尿病状态下影响再灌注损伤救援激酶信号通路,导致GSK-3β活性(去磷酸化水平)增高有关.     

糖尿病大鼠在心肌缺血及二氮嗪预处理中一氧化氮信号通路表达受抑的研究

目的:探讨糖尿病对心肌缺血预处理(IPC)及二氮嗪预处理(DPC)效果的影响及其机制。方法:取糖尿病及非糖尿病SD大鼠各40只,建立离体心脏Langendorff灌注模型,各分为5组(每组8只):①对照组(Con组):仅行全心灌流120min,不做其他处理;②缺血再灌注组(I/R组):心脏平衡灌流30min,缺血30min,再灌注60min;③IPC组:缺血30min前,心脏平衡灌流10min,2次缺血5min,再灌注5min后,余同I/R组;④DPC组:心脏依次平衡灌流10 min,重复2次灌注含二氮嗪(浓度为100μmol/L)的K-H液5min,间隔灌注K-H液5min,余同I/R组;⑤二甲基亚砜组(DMSO组):用DMSO取代二氮嗪,过程与DPC组处理相同。比较各组冠状动脉流出液中肌酸激酶(CK)、心肌组织中丙二醛(MDA)、超氧化物歧化酶(SOD)活性及环磷酸鸟苷(cGMP)、NO、一氧化氮合成酶(NOS)含量的变化。电镜对心肌线粒体行Flameng评分。结果:①灌流液CK含量:缺血前各组间差异无统计学意义(P0.05)。再灌注后CK含量比较(与I/R比较):非糖尿病大鼠的IPC组和DPC组明显降低(P0.01);而糖尿病大鼠的IPC组和DPC组无明显降低,(与I/R组比较)差异无统计学意义(P0.05)。②心肌MDA含量:非糖尿病大鼠的IPC组和DPC组含量明显比I/R组降低(P0.01),而糖尿病大鼠的各组差异无统计学意义(P0.05)。心肌SOD含量:非糖尿病大鼠的IPC组和DPC组明显高于I/R组(P0.01),而糖尿病大鼠的各组间差异无统计学意义(P0.05)。③心肌cGMP、NO、NOS含量的变化:非糖尿病大鼠的IPC组及DPC组与I/R组比较明显增加(P0.01);而糖尿病大鼠的组间比较差异无统计学意义(P0.05)。④心肌线粒体Flameng评分:糖尿病大鼠各组间比较,差异无统计学意义(P0.05)。结论:IPC及DPC对非糖尿病大鼠心肌有明显的保护作用,能正调NO、cGMP及NOS的表达。而糖尿病可抑制IPC及DPC的心肌保护作用,其机制可能与糖尿病大鼠心肌NO信号通路表达受抑制有关。     

血管紧张素ⅡⅠ型受体阻断剂抑制大鼠缺血-再灌注模型心肌细胞凋亡

目的观察血管紧张素ⅡⅠ型受体阻断剂losartan对大鼠心肌缺血-再灌注模型心肌细胞凋亡及凋亡相关蛋白P53和Bcl-2表达的影响。方法Wistar大鼠随机分为三组(1)假手术组(5只);(2)缺血-再灌注组(6只)结扎左冠状动脉45min,再灌注4h;(3)losartan组(6只)缺血前15min和再灌注1h分别静脉注射losartan10mg/kg。采用TUNEL和DNA电泳方法检测心肌细胞凋亡,免疫组织化学方法检测心肌组织P     

缺血再灌注损伤对SD乳鼠器官型脑片神经再生的影响

目的探讨缺血再灌注损伤对SD乳鼠器官型脑片中神经再生的影响。方法制备P3SD乳鼠的全脑器官型脑片,随机分为缺血再灌注组和正常对照组,观察脑片生长情况,培养3天后,两组再分别分为2个亚组,分别给予药物和空白干预,依次列为Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组,通过倒置显微镜及免疫荧光染色观察各组脑片在1、3、7天的改变。结果缺血再灌注组室下区、海马齿状回可见巢蛋白阳性新生细胞,而正常对照组未见新生细胞;药物干预后,两组均出现大量新生细胞,但正常对照组单位区域新生细胞数量多于缺血再灌注组(P<0.01);Ⅲ组较Ⅰ、Ⅱ组明显增多(P<0.01),随着培养时间延长,两组新生细胞均向外迁移,上述区域新生细胞密度逐渐减少。结论缺血再灌注损伤可以促进SD乳鼠器官型脑片神经再生,但同时也损伤了神经再生的潜能。     

The effects of verapamil vs. allopurinol on intestinal ischemia/reperfusion injury in rats. "An experimental study"

BACKGROUND/AIMS: Although studies have reported that xanthine oxidase inhibitors or calcium channel blockers attenuate the ischemia-reperfusion injury in several organ systems, no comparative study exists on the significance of each of these pathways. To study this, in anesthetized Wistar Albino rats, a surgical model for intestinal ischemia-reperfusion injury was employed. METHODOLOGY: In experimental animals, after laparotomy, the superior mesenteric artery was occluded for 30 min, followed by a 2-h period of reperfusion; control rats underwent only a sham laparotomy procedure. One group of experimental animals was pretreated intraperitoneally with the calcium channel blocker verapamil (0.3 mg/kg), another group with the xanthine oxidase inhibitor allopurinol (100 mg/kg), the third group received no pretreatment. Plasma lactate, malondialdehyde and glutathione levels as well as intestinal tissue malondialdehyde and glutathione levels were measured to assess for possible protective effects. Histologic evaluation of the extent of injury was also performed. RESULTS: Irreversible tissue damage was depicted in the untreated group, and partially in the allopurinol pretreatment group by histologic examination. Ischemia-reperfusion injury was reversible in the verapamil group. The laboratory results also supported these findings. CONCLUSIONS: Protective effects of verapamil on ischemia-reperfusion injury have been found to be significantly (p<0.0001) more effective compared to allopurinol.     

MicroRNAs与心肌缺血再灌注损伤

MicroRNAs（miRNAs）是一类高度保守的非编码小分子RNA,经转录后调节细胞的增殖、迁移、分化、凋亡和免疫应答等。miRNAs与心血管疾病发生发展密切相关。心肌缺血后多种miRNA。异常表达,它们在介导心肌缺血再灌注损伤和调控心肌缺血保护环节中起重要作用,可作为诊断缺血再灌注损伤的标志物和潜在治疗靶点。     

糖尿病教育对藏族糖尿病患者代谢功能改善的研究

目的:探讨糖尿病教育对藏族糖尿病患者代谢功能改善的作用。方法:在拉萨市娘热乡筛选113名糖尿病患者,测定体重指数、血脂、糖基化血红蛋白。对所有患者进行药物、生活方式干预。分为教育组与对照组,教育组采用面对面随访,半年后测定代谢指标。结果:糖尿病教育组(56人)代谢指标均优于(P<0.05)对照组(57人)。各项指标教育组均较干预前改善,而对照组无改善。结论:藏族糖尿病患者面对面的随访方式切实有效。     

灵芝对链脲佐菌素诱导糖尿病大鼠肾脏的保护作用及其机制

目的 探讨灵芝(GL)对链脲佐菌素诱导的糖尿病(DM)大鼠肾脏的保护作用及其机制.方法将30只雄性SD大鼠随机均分为对照组、DM组及GL组.腹腔注射链脲佐菌素诱导大鼠造成DM模型,治疗组用GL治疗性灌胃.8周后,用酶联免疫吸附法检测各组大鼠血清高敏C反应蛋白(hs-XRP),免疫组化法检测肾皮质单核细胞趋化蛋白1(MCP-1)蛋白表达.结果 DM组血清hs-CRP、肾小球MCP-1蛋白表达较对照组升高,GL组较DM组减少,病理变化明显好转(P均<0.01).结论 GL可能通过降低hs-CRP、MCP-1表达而减轻炎症反应,起到保护DM大鼠肾脏的作用.     

Expression of lectin-like oxidized low-density lipoprotein receptors during ischemia-reperfusion and its role in determination of apoptosis and left ventricular dysfunction

OBJECTIVES: The goal of this study was to determine the role of lectin-like oxidized low-density lipoprotein receptors (LOX-1), a recently identified oxidized low-density lipoprotein (ox-LDL) receptor, in ischemia-reperfusion injury to the heart. BACKGROUND: Reactive oxygen species (ROS) released during ischemia-reperfusion oxidize low-density lipoproteins; LOX-1 is upregulated by ox-LDL and ROS, and is involved in cell injury. METHODS: Anesthetized rats were subjected to left coronary artery ligation for 60 min (n = 10, ischemia group), or ischemia followed by 60 min of reperfusion (n = 30, ischemia-reperfusion group). Rats in the latter group were treated with saline, the LOX-1 blocking antibody JXT21 (10 mg/kg), or nonspecific anti-goat immunoglobulin G (IgG) (10 mg/kg). Ten other rats underwent thoracotomy without coronary ligation (sham control). RESULTS: Ischemia-reperfusion was associated with an increase in LOX-1 expression, lipid peroxidation and apoptosis, a large infarct area, and a decrease in left ventricular function (all, p < 0.01 vs. sham control and ischemia alone groups). Treatment of rats with LOX-1 antibody prevented ischemia-reperfusion-induced upregulation of LOX-1. Importantly, the LOX-1 antibody reduced apoptosis by 48%, lipid peroxidation by 39%, and myocardial infarct size by 45%, and improved left ventricular function (first derivative of pressure measured over time: -47% to -18%, p < 0.01). Nonspecific IgG had no effect. CONCLUSIONS: Lectin-like oxidized low-density lipoprotein receptors are upregulated during myocardial ischemia-reperfusion, and appear to be associated with apoptosis, necrosis, and left ventricular functional deterioration.     

Finger and penile tactile sensitivity in sexually functional and dysfunctional diabetic men

Summary Tactile sensitivity of the penis is related to sexual functioning, however its role in diabetic erectile problems is unclear. We evaluated penile sensitivity in 10 diabetic men with erectile dysfunction, 17 sexually functional diabetic men and 14 control subjects. Finger and penile thresholds and ratings of intensity and pleasantness for finger and penis were assessed using vibrotactile stimulation. Glycosylated haemoglobin and total and bioavailable testosterone measurements were determined and subjects completed self-reports on sexual function. Diabetic men with erectile problems had higher values of glycosylated haemoglobin than sexually functional diabetic men (p = 0.02) and both groups had lower bioavailable testosterone than control subjects (p K 0.05). Sexually dysfunctional diabetic men had a higher finger threshold than the other two groups (p < 0.01). Penile threshold for the sexually dysfunctional group was also marginally higher compared with the functional diabetic group (p < 0.052) but did not differ from control subjects (p = 0.09). Diabetic men with erectile dysfunction exhibited different response patterns than sexually functional men on dimensions of intensity and pleasantness to penile stimulation. Although these data do not directly implicate subjective response to penile stimulation in diabetic erectile problems, they suggest such anomalous response could be one contributing factor. [Diabetologia (1999) 42: 336–342] Received: 28 April 1998 and in final revised form: 30 October 1998     

类缺血再灌注损伤对体外培养神经干细胞活性和胞内钙浓度及增殖的影响

目的观察类缺血再灌注损伤对体外培养的胚胎小鼠纹状体神经干细胞活性、胞内Ca2+浓度以及增殖的影响。方法将体外培养的小鼠神经干细胞分为类缺血再灌注组、药物预处理组(1μmol/L氟桂利嗪)和对照组。前两组进行类缺血处理并分别于再灌注0、30 min、1、2、3 h检测细胞内Ca2+浓度,于03、0 min、12、、31、2、24、36、486、0 h检测细胞活性,对照组在相同时间点检测细胞活性,比较3组间细胞内Ca2+浓度及细胞活性的差异。结果类缺血再灌注后神经干细胞内游离Ca2+浓度显著升高,在相同时间点药物预处理组胞内Ca2+浓度均低于类缺血再灌注组,其中0、30 min1、h时有显著性差异(P<0.05);类缺血再灌注后细胞活性降低,在相同时间点药物预处理组细胞活性均高于类缺血再灌注组,其中03、0 min、1、2 h时差异显著(P<0.05)。再灌注后12~60 h类缺血再灌注组和药物预处理组的细胞增殖率明显高于对照组(P<0.01)。结论类缺血再灌注可以导致胞内Ca2+浓度升高及神经干细胞活性的降低,氟桂利嗪预处理可抑制胞内Ca2+的升高,减轻神经干细胞的损伤;另外类缺血再灌注后存活的神经干细胞的增殖能力增强。     

Effects of Folic Acid on Cardiac Myocyte Apoptosis in Rats with Streptozotocin-induced Diabetes Mellitus

BACKGROUNDS: The effect of folic acid on cardiac myocyte apoptosis secondary to diabetes is unknown. METHODS: Diabetic rats were divided into diabetic control (DC, n = 11), low-dose (LDF, 0.4 mg/kg/day, n = 12) and high-dose (HDF, 1.2 mg/kg/day, n = 12) folic acid groups. Non-diabetic rats (n = 11) were used as the normal control (NC). RESULTS: After 11 weeks of treatment, compared with the NC group, the DC group showed a reduced blood levels of reactive oxygen species (ROS, P < 0.01). The rate of cardiac myocyte apoptosis in the diabetic control group was also greater than in the non-diabetic control group (P < 0.01). In folic acid-treated rats, the blood levels of ROS was higher than in the diabetic control group (P < 0.05). There was a dose-dependent reduction in the rate of cardiac myocyte apoptosis in the folic acid groups (P < 0.01), and this was accompanied by an increased level of anti-apoptotic protein Bcl-2 and decreased level of pro-apoptotic protein Bax and Fas (P < 0.01). CONCLUSIONS: Dietary folic acid supplementation diminishes the cardiac myocyte apoptosis in streptozotocin-induced diabetes. The apoptosis suppression is accompanied by an increase in the expression of Bcl-2 and a decrease in Bax and Fas.