[Effect of bone mesenchymal stem cells transplantation on malignant ventricular arrhythmia induced byelectrophysiological stimulation in a mini-swine model of acute myocardial infarction].
OBJECTIVE
To investigate the effects of autologous bone mesenchymal stem cells (MSC) transplantation on malignant arrhythmia induced by electrophysiological (EP) stimulation and cardiomyocyte ion channels remodeling in a mini-swine model of acute myocardial infarction (AMI).


METHODS
Immediately after AMI (LAD occluded for 120 min), MSC (10 x 10(7), labeled by colloidal gold and co-cultivated with 5-azacytidine, 5-aza, n = 12) or equal volume saline (n = 10) were injected through over-the-wire (OTW) balloon in LAD at distal over D(1). EP stimulation is performed after 2 hours and 4 weeks in both groups to induce arrhythmia. The variance of heterogeneity of sodium currents (I(Na)) and I(Na) steady-state inactivation curves in different zones of infracted wall were investigated by patch clamp technology and the relationship between ionic channel and ventricular arrhythmia is analyzed.


RESULTS
EP induced malignant ventricular arrhythmia (VT) rate was similar (MSC 75% vs. saline 90%, P = 0.455) at 2 hours post AMI and was significantly lower in MSC group (25% vs. 80%, P = 0.012) at 4 weeks post AMI. The Peak I(Na) current densities of the Endo, Media and Epi were significantly lower in MSC group [(-14.04 +/- 3.82) pA/pF, (-29.26 +/- 5.70) pA/pF, (-12.43 +/- 3.04) pA/pF] compared those in saline group [(-9.71 +/- 3.38) pA/pF, (-18.98 +/- 4.05) pA/pF, (-8.47 +/- 3.34) pA/pF, all P < 0.05]. The I(Na) steady-state inactivation curves of the Epi, Endo and Media in mini-swine with VT in MSC group [(-126.2 +/- 10.9) mV, (-106.7 +/- 11.9) mV, (-105.4 +/- 11.0) mV] were similar as those in saline group with VT [(-129.1 +/- 10.9) mV, (-112.2 +/- 9.9) mV, (-109.7 +/- 9.2) mV, all P > 0.05] while significantly lower compared to MSC group without VT [(-93.1 +/- 13.8) mV, (-95.2 +/- 15.5) mV, (-103.4 +/- 8.7) mV, all P < 0.05]. The multiple logistic regression analysis showed that I(Na) current density (RR = 1.449, 95% CI 1.276 - 2.079, P = 0.029) and I(Na) steady-state inactivation curves (RR = 1.092, 95% CI 1.008 - 1.917, P = 0.012) were the independent factors for reduced VT.


CONCLUSIONS
Autologous MSC attenuated malignant ventricular arrhythmia induced by EP at 4 weeks in mini-swine with AMI which might due to altered cardiomyocyte ion channels remodeling induced by MSC.
Qi
Xiao-yong
XY
Heart Center, Hebei General Hospital, Shijiazhuang 050051, China. xiaoyong_q@yahoo.com
Meng
Cun-liang
CL
Dang
Yi
Y
Zhang
Jun
J
Li
Shu-ren
SR
D000818:Animals; D001145:Arrhythmias, Cardiac / Q000209:etiology*; D016026:Bone Marrow Transplantation; D004195:Disease Models, Animal; D005260:Female; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D009203:Myocardial Infarction / Q000503:physiopathology* / Q000601:surgery*; D018408:Patch-Clamp Techniques; D013552:Swine; D013556:Swine, Miniature; D014182:Transplantation, Autologous