鸟苷酸交换因子DOCK1对心肌细胞存活的影响

Effect of Guanine Nucleotide Exchange Factor DOCKl on Survival of Cardiomyocytes

目的探讨鸟苷酸交换因子DOCK1对心肌细胞存活的影响。方法用重组真核质粒pCXN2-Flag-hDOCK1(人DOCK1过表达质粒),pCXN2-Flag(空质粒)及空白试剂分别转染大鼠源H9C2心肌细胞,并给予缺氧/复氧(H/R)干预。将心肌细胞分为空白组,空质粒组,DOCK1过表达组,空白+H/R组,空质粒+H/R组,DOCK1过表达+H/R组。用RT-PCR测定DOCK1mRNA水平。流式细胞术、MTT分别测定细胞的凋亡率和增殖率。结果 DOCK1过表达组(1.51±0.169)%,(2.49±0.442)%,(38.94±0.580)%,(P<0.05)较空白组(-),(3.61±0.334)%,(20.64±0.720)%,(P<0.05)和空质粒组(-),(3.66±0.373)%,(22.29±0.838)%,(P<0.05),DOCK1过表达+H/R组1.03±0.171,(5.38±0.431)%,(17.33±0.343)%,(P<0.05)较空白+H/R组[(-),(2.49±0.442)%,(7.95±0.322)%,(P<0.05)和空质粒+H/R组(-),(10.32±0.388)%,(792±0.351)%,(P<0.05),人的DOCK1RNA分别显著增加、心肌细胞凋亡率分别显著降低及增殖率分别显著增加。较DOCK1过表达组,DOCK1过表达+H/R组人的DOCK1mPNA显著降低。较空白组(0.64±0.145),(P<0.05)、空质粒组(0.60±0.182),(P<0.05)及DOCK1过表达组(0.60±0.182),(P<005),空白+H/R组(0.30±0.115),(P<0.05)、空质粒+H/R组(0.36±0.101),(P<0.05)及DOCK1过表达+H/R组(1.03±0.171),(P<0.05)大鼠的DOCK1mRNA分别显著降低、心肌细胞凋亡率分别显著增加及增殖率分别显著降低。结论 DOCK1可抑制H9C2心肌细胞的凋亡,促进H9C2心肌细胞的增殖、存活;且DOCK1可抑制H/R诱导的H9C2心肌细胞凋亡增加及增殖、存活的降低。

Objective To observe the effect of guanine nucleotide exchange factor DOCK1 on the survival of cardiomyocytes. Methods Rat-de- rived H9C2 cardiomyocytes were transfected with eukaryotic expression recombinant plasmid pCXN2-Flag-hDOCKI （human DOCK1 overex- pression plasmid）, pCXN2-Flag （empty plasmid） and blank, and treated with hypoxia/reoxygenation （H/R） respectively. The cardiomyo- cytes were divided into blank group, empty plasmid group, DOCK1 overexpression group, blank ＋ H/R group, empty plasmid ＋ H/R group and DOCK1 overexpression ＋ I-I/R group. The expressions of DOCK1 mRNA was detected by RT-PCR. Apoptosis and cell proliferation rates of the cardiomyocytes were analyzed by flow cytometry and MTT respectively. Results Compared with blank （ - ）, （ 3.61 ± 0. 334 ） %, （ 20.64 ±0. 720） %, （ P 〈 0.05 ） and empty plasimd groups （ - ）, （3.66 ± 0. 373 ） %, （ 22.29 ± 0. 838 ） %, （ P 〈 0. 05 ）, human DOCK1 mRNA and the cell proliferation rate Were increased,and the apoptosis rate was decreased significantly in the DOCK1 overexpression group （1.51±0.169）,（ 2.49 ±0.442）%,（ 38.94 ±0.580）%,（P 〈0.05） respectively. Compared with blank ＋H/R（ -）,（2.49 ± 0.442）%,（7.95±0.322）%,（P〈0.05） and empty plasimd＋1-1/R groups（ -）,（10.32±0.388）%,（ 7.92±0.351）%,（P〈 0. 05 ） , human DOCK1 mRNA and the cell proliferation rate were increased, and the apoptosis rate was decreased significantly in the DOCK1 overexpression ＋ H/R group （ 1.03 ± 0. 171 ）, （5.38 ±0. 431 ） % , （ 17. 33 ± 0. 343 ） % , （ P 〈 0.05 ） respectively. Compared with DOCK1 overexpression group, human DOCK1 mRNA was decreased significantly in the DOCK1 overexpression ＋ H/R group. Compared with blank （0. 64 ± 0. 145 ）, （ P 〈 0. 05 ）, empty plasmid （ 0. 60±0. 182 ）, （ P 〈 0.05 ） and DOCK1 overexpression groups （ 0. 60 ±0. 182 ）, （ P 〈 0. 05 ）, rat DOCK1 mRNA and the cell proliferation rate were decreased, and the apoptosis rate was increased significantly in the blank ＋ H/ R（0.30± 0. 115 ）, （ P 〈 0. 05 ）, empty plasimd ＋ H/R （ 0. 36 ± 0. 101 ）, （ P 〈 0. 05 ） and DOCK1 overexpression ＋ H/R groups （ 1.03± 0. 171 ） , （ P 〈0.05 ） respectively. Conclusion DOCK1 can inhibit apoptosis ,and ＂promote cell proliferation and survival in the H9C2 cardio- myocytes;DOCK1 also can inhibit the H/R-induced increase of apoptosis and decrease of cell proliferation and survival in the H9C2 cardio- myocytes.