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Objective: To explore the impact and related mechanisms of stromal cell-derived factor-1α (SDF-1α) on serum deprivation-induced apoptosis of cardiac stem cells (CSCs)., Methods: CSCs were isolated from adult mouse heart tissue and cultured in vitro. Obtained cells were purified using magnetic-activated cell sorting (MACS) with c-kit magnetic beads. C-kit(+)CSCs were divided into five groups: normal control group, serum deprivation group, serum deprivation+SDF-1α group, serum deprivation+SDF-1α+AMD3100 group, serum deprivation+SDF-1α+LY294002 group. Cell apoptosis was assessed using the DeadEnd Colorimetric TUNEL System and flow cytometry analyses with an Annexin V-FITC Apoptosis Detection Kit. The viability of CSCs was assessed by CCK-8. The protein expression of Bcl-2 and phosphorylated Akt were detected by Western blot. The caspase-3 activity was determined using caspase-3 Colorimetric Assay Kit., Results: After magnetic separation, more than 85% of cardiosphere derived cells were positive for c-kit expression. Compared with the normal control group, the apoptosis rate of serum deprivation group was significantly increased[(27.03 ± 0.80)% vs. (1.51 ± 0.54)%, P < 0.01], which could be significantly reduced by SDF-1α in a concentration dependent manner and peak effect was seen with 100 ng/ml SDF-1α[(10.67 ± 1.06)% vs. (27.03 ± 0.80)%, P < 0.01]. The expressions of p-Akt and Bcl-2 were significantly increased and the activity of caspase-3 was significantly decreased in serum deprivation+SDF-1α group compared to serum deprivation group (P < 0.01). Further more, the expression of p-Akt and Bcl-2 were significantly decreased and the activity of caspase-3 was increased in both serum deprivation+SDF-1α+AMD3100 group and serum deprivation+SDF-1α+LY294002 group compared to serum deprivation+SDF-1α group (P < 0.01)., Conclusions: SDF-1α reduces serum deprivation induced CSCs apoptosis via modulating PI3K/Akt signaling pathway.

Objective: to explore the value of in vivo dynamic monitoring of abdominal aortic atherosclerosis (AS) by high field magnetic resonance (MR) imaging (MRI) in apoE-/- mice fed a high fat diet or infused with angiotensin., Methods: high fat diet or angiotensin II infusion was applied to apoE-/- mice for establishment of abdominal aortic atherosclerosis model. Abdominal aorta MRI was performed at 3 time points (baseline, 3 and 6 months) in 13 high fat diet fed apoE-/- mice aged 10-12 months and 3 wild-type control mice; 10 apoE-/- mice aged 6 months were infused with angiotensin II (1000 or 500 ng × kg(-1)× min(-1), n = 5 each) or saline for 14 d through Osmotic minipump. The abdominal aortic artery MRI was performed at baseline and 14 d after infusion. Black blood sequences of FLASH T1 weighted images and Proton density weighted-T2 weighted dual echo images were obtained. At each observation time post MRI, mice (n = 3, 5 and 5 for high fat diet group and n = 5 and 5 for angiotensin II infusion group) were sacrificed for pathological examination of the abdominal artery., Results: (1) the abdominal aorta atherosclerosis was identified in both high fat diet and angiotensin II treated apoE-/- mice but in WT controls. Lesion progression was documented in high fat diet fed apoE-/- mice characterized by significantly increased vessel wall (a marker of atherosclerotic burden, F = 29.94, P < 0.05) and gradually increased plaque signal in PDW and T2W images. Results derived from MRI corresponded histopathology findings in high fat diet fed apoE-/- mice (correlative coefficient = 0.84, 0.95, 0.90, P < 0.05, respectively). Both MRI and histology showed increased lipid composition and decreased fibrotic composition in these mice. (2) The vessel wall area increased significantly [(1.21 ± 0.21) mm(2) vs. (2.65 ± 0.48) mm(2), P < 0.05] and the abdominal aortic dissection aneurysms was identified in apoE-/- mice infused with high angiotensin II. The vessel wall area also increased [(0.85 ± 0.11) mm(2) vs. (1.01 ± 0.17) mm(2), P < 0.05] in low angiotensin II infused apoE-/- mice and the coefficient between MR and histopathology is 0.934., Conclusion: abdominal aortic unstable plaque model could be established by both high fat diet and angiotensin II infusion in apoE mice, angiotensin II infusion can transiently accelerate the progression of AS and can induce abdominal aortic dissection. Serial MR black blood sequences could demonstrate the development and progression of atherosclerosis in mouse abdominal aorta with excellent agreement to histopathology finding in terms of atherosclerotic burden and plaque composition. Thus, MRI appears to be a useful tool for in vivo AS plaque dynamic monitoring in mice.

Objective: To observe the effect of intracoronary transfer of autologous HO-1 overexpressed MSCs in porcine model of myocardial ischemia (1 h)/reperfusion., Methods: Apoptosis was assayed and cytokine concentrations in supernatant were measured in cells exposed to hypoxia-reoxygen in vitro. In vivo, Chinese male mini-pigs were allocated to the following treatment groups: control group (saline), MSCs group (MSCs), MSCs transfected with pcDNA3.1-nHO-1 (HO-1-MSCs). 1 x 10(7) of autologous stem cells or identical volume of saline was injected intracoronary into porcine hearts 1 h after ischemia. MRI assay and postmortem analysis were assessed 3 months after stem cell transplantation., Results: In vitro, cell apoptosis rate post hypoxia-reoxygen was significantly reduced in HO-1-MSCs group (30.30% +/- 7.64%) compared with that in MSCs group (56.93% +/- 4.68%, P < 0.001) and LacZ-MSCs group (55.88% +/- 4.38%, P < 0.001), VEGF was also significantly upregulated in HO-1-MSCs group [(768.44 +/- 78.38) pg/ml] compared with that in MSCs group [(555.27 +/- 67.67) pg/ml, P < 0.001] and LacZ-MSCs group [(522.97 +/- 71.45) pg/ml, P < 0.001]. In vivo, cardiac function was significantly improved in both MSCs transplantation groups compared to saline group (all P < 0.05 vs.saline) and the left ventricular ejection fraction was significantly higher in HO-1-MSCs group compared with that in MSCs group at 3 months after transplantation (53.50% +/- 2.09% vs. 49.54% +/- 2.74%, P = 0.017), capillary density in the peri-infarct area was also significantly higher in HO-1-MSC group than that in MSCs group [(14.59 +/- 2.39)/HPF vs. (11.78 +/- 2.48)/HPF, P = 0.033]., Conclusions: Efficacy of HO-1 overexpressed MSCs on improving cardiac function and promoting angiogenesis was greater than those by MSCs in this porcine ischemia/reperfusion model.

Objective: To explore the association between the gene mutation of transcription factor Nkx2.5 and Chinese patients with congenital heart disease (CHD)., Methods: Polymerase chain reaction (PCR) and DNA sequencing were used to check 99 CHD patients and 90 normal control subjects from the Zhong Da Hospital of Southeast University. After amplifying the exons 1 of the Nkx2.5 gene by PCR, we purified the PCR products and conducted the sequencing reaction, analyzed the mutation screening of the exon 1 of the Nkx2.5, investigated whether or not the Nkx2.5 is related with the CHD in Chinese population., Results: A mutation (A239G) in the exon 1 of the Nkx2.5 was identified in 3 of 90 normal control subjects and 12 of 99 CHD patients, including 3 of 24 with VSD, 7 of 35 with ASD, 1 of 13 with PS and 1 of 21 with PDA., Conclusion: There are some associations between the Nkx2.5 gene mutation and occurrence of congenital heart disease in Chinese people.