BMSCs移植对糖尿病大鼠心功能的影响

EFFECT OF BMSCs TRANSPLANTATION ON CARDIAC FUNCTION OF DIABETES MELLITUS RATS

目的探讨对糖尿病(diabetes mellitus,DM)大鼠心室壁注射移植BMSCs后,BMSCs对DM大鼠心功能的影响及其机制。方法取3～4月龄雄性SD大鼠骨髓分离纯化BMSCs,取第5代BMSCs行DAPI标记。另取清洁级近交系SD雄性大鼠30只,体重约250g,随机分为正常对照组(A组)、DM组(B组)、细胞移植组(C组),每组10只。B、C组实验动物以高脂饲料喂养4周、30mg/kg链尿佐菌素腹腔注射,再以高脂饲料喂养4周制备2型DM动物模型。造模成功后B、C组实验动物心室壁分别注射PBS及DAPI标记的第5代BMSCs(1×105个/μL,160μL),继续高脂饲料喂养8周后,TUNEL法检测各组心肌细胞凋亡,多导生理记录仪检测各组大鼠心功能,Western blot和免疫组织化学检测各组心肌APPL1蛋白的表达,硝酸还原酶法测定各组大鼠NO含量。A组大鼠以基础饲料喂养16周后进行以上相关检测。结果A组心肌细胞凋亡率、APPL1含量、左心室内压最高下降速率(leftventricular-dP/dt,LV-dP/dt)、左心室舒张末期压力(leftventricular end-diastolic pressure,LVEDP)、NO含量分别为:6.14%±0.02%、2.79±0.32、(613.27±125.36)mmHg/s(1mmHg=0.133kPa)、(10.06±3.24)mmHg、(91.54±6.15)nmol/mL;与A组比较,B组心肌细胞凋亡率45.71%±0.04%明显增加,APPL1表达1.08±0.24明显减少,LV-dP/dt(437.58±117.58)mmHg/s显著下降,LVEDP(17.89±2.35)mmHg明显上升,NO含量(38.91±8.67)nmol/mL显著下降,差异均有统计学意义(P<0.05);与B组比较,C组大鼠心肌细胞凋亡率27.43%±0.03%明显下降,APPL1表达2.03±0.22显著增加,LV-dP/dt(559.38±97.37)mmHg/s显著增加,LVEDP(12.55±2.87)mmHg显著下降,NO含量(138.79±7.23)nmol/mL增加,差异均有统计学意义(P<0.05)。结论BMSCs移植可改善DM大鼠心脏舒张功能,其机制可能与激活APPL1信号途径,增加NO产生有关。

Objective To observe the effect of BMSCs on the cardiac function in diabetes mellitus （DM） rats through injecting BMSCs into the ventricular wall of the diabetic rats and investigate its mechanism. Methods BMSCs isolated from male SD rats （3-4 months old） were cultured in vitro,and the cells at passage 5 underwent DAPI labeling. Thirty clean grade SD inbred strain male rats weighing about 250 g were randomized into the normal control group （group A）,the DM group （group B）,and the cell transplantation group （group C）. The rats in groups B and C received high fat forage for 4 weeks and the intraperitoneal injection of 30 mg/kg streptozotocin to made the experimental model of type II DM. PBS and DAPI-labeled passage 5 BMSCs （1 × 10^5/μL,160 μL） were injected into the ventricular wall of the rats in groups B and C,respectively. After feeding those rats with high fat forage for another 8 weeks,the apoptosis of myocardial cells was detected by TUNEL,the cardiac function was evaluated with multi-channel physiology recorder,the myocardium APPL1 protein expression was detected by Western blot and immunohistochemistry test,and the NO content was detected by nitrate reductase method. Group C underwent all those tests 16 weeks after taking basic forage. Results In group A,the apoptosis rate was 6.14% ± 0.02%,the AAPL1 level was 2.79 ± 0.32,left ventricular -dP/dt （LV-dP/dt） was （613.27 ± 125.36） mm Hg/s （1 mm Hg=0.133 kPa）,the left ventricular end-diastolic pressure （LVEDP） was （10.06 ± 3.24） mm Hg,and the NO content was （91.54 ± 6.15） nmol/mL. In group B,the apoptosis rate was 45.71% ± 0.04%,the AAPL1 level 1.08 ± 0.24 decreased signifi cantly when compared with group A,the LV-dP/dt was （437.58 ± 117.58） mm Hg/s,the LVEDP was （17.89 ± 2.35） mm Hg,and the NO content was （38.91±8.67） nmol/mL. In group C,the apoptosis rate was 27.43% ± 0.03%,the APPL1 expression level was 2.03 ± 0.22,the LV -dP/dt was （559.38 ± 97.37） mm Hg/ s,the LVEDP was （12.55 ± 2.87） mm Hg,and the NO content was （138.79 ± 7.23） nmol/ mL. For the above mentioned parameters,there was signifi cant difference between group A and group B （P 〈 0.05）,and between group B and groupC （P 〈 0.05）. Conclusion BMSCs transplantation can improve the cardiac function of diabetic rats. Its possible mechanism may be related to the activation of APPL1 signaling pathway and the increase of NO content.