Lianglong Chen

Transplantation with survivin-engineered mesenchymal stem cells results in better prognosis in a rat model of myocardial infarction

To investigate the effect of survivin (SVV)‐engineered mesenchymal stem cells (MSCs) on post‐infarction cardiac performance and remodelling in rats.

Low serum adropin is associated with coronary atherosclerosis in type 2 diabetic and non-diabetic patients.

Abstract Background: Diabetes increases the risk and severity of atherosclerosis. Adropin, a metabolic homeostasis-related protein, has been implicated in the maintenance of metabolic homeostasis. We examined the relationship between serum adropin level and angiographic severity of coronary atherosclerosis in diabetic and non-diabetic patients. Methods: A total of 392 patients with suspected coronary artery disease, who underwent coronary angiography, were assigned into the type 2 diabetic and non-diabetic groups and also classified into four groups according to the quartiles of adropin level. Venous serum samples were collected for adropin measurement by enzyme-linked immunosorbent assay and for biochemistry assay. The angiographic severity of coronary atherosclerosis was assessed by Gensini, Friesinger, and SYNTAX scores. Results: Compared with non-diabetic patients, diabetic patients had lower serum adropin level and higher Gensini, Friesinger and SYNTAX scores (all p<0.001). Serum adropin level was inversely correlated with the Gensini, Friesinger and SYNTAX scores (rs=–0.389, –0.390 and –0.386, respectively, all p<0.001) among all patients. Low adropin level was an independent predictor of clinically relevant coronary atherosclerosis (SYNTAX score >11), both in diabetic patients [odds ratio (OR) 0.66, 95% confidence interval (CI) 0.53–0.83; p<0.001] and in non-diabetic patients (OR 0.51, 95% CI 0.35–0.74; p<0.001). Conclusions: Serum adropin level was significantly lower in type 2 diabetic patients than in non-diabetic patients and was inversely and independently associated with angiographic severity of coronary atherosclerosis, suggesting that serum adropin serves as a novel predictor of coronary atherosclerosis.

Ciglitazone inhibits oxidized-low density lipoprotein induced immune maturation of dendritic cells.

Background The peroxisome proliferator-activated receptor (PPAR) activation has generally been shown to have anti-inflammatory effects and dendritic cells (DCs) are the most efficient antigen presenting cells that play an active role in the development of atherosclerosis. The effects of PPARγ on DCs maturation and immune function remain unknown now and we, therefore, studied the influence of PPARγ agonist ciglitazone on the maturation and immune function of DCs. Methods Human monocytes were purified and immature DCs derived; ciglitazone (25 μmol/L) was added to the medium for 24 hours; ox-LDL (50 μg/ml) was then added to the medium for another 24 hours. The immunophenotypic expressions (CD1a, CD40, CD86, and HLA-DR) were analyzed by FACS and endocytosis function by FITC-dextran and the cytokines secretions of culture supernatants (IL-12,IL-10,TNFα, and IL-2) were measured with ELISA. Results Ciglitazone reduced ox-LDL induced immunophenotypic expressions of DCs (CD40, CD1a, and HLA-DR). Ox-LDL inhibited the endocytosis of DCs, which was prevented by ciglitazone; ciglitazone attenuated ox-LDL induced cytokine secretions of DCs (IL-12, 116 ± 29 versus 34 ± 3 pg/ml*; IL-10, 49 ± 1 versus 28 ± 9 pg/ml*; TNFα, 46 ± 16 versus 24 ± 8pg/ml*, *P < 0.05 compared with ox-LDL, respectively). Conclusion Our study suggested that one of the anti-inflammatory mechanisms of PPAR-γ agonist ciglitazone was mediated by inhibiting the ox-LDL induced maturation and immune function of DCs.

Enhanced therapeutic effects of mesenchymal stem cells on myocardial infarction by ischemic postconditioning through paracrine mechanisms in rats.

Ischemic postconditioning (IPC) is cardioprotective against ischemia-reperfusion injury which impairs the myocardial micro-environment and reduces the survival of transplanted cells. We tested the hypothesis that IPC may improve the survival of transplanted cells and enhance their therapeutic effects. In this study, bone marrow-derived mesenchymal stem cells (BMSCs) from Sprague-Dawley rats were infected with lentivirus carrying green fluorescent protein (GFP) gene. The left main coronary arteries of rats were occluded for a 30-min ischemia, followed by a 72 h or 28 d reperfusion. IPC was induced by 3 cycles of 10s reperfusion and 10s ischemia before sustained reperfusion. GFP-BMSCs were intramyocardially injected at 2h reperfusion. At 70 h after transplantation, IPC treatment increased the level of interleukin-10, B-cell leukemia-lymphoma-2 (BCL-2), and vascular endothelial and basic fibroblast growth factor (VEGF and bFGF), and decreased the level of tumor necrosis factor-α, interleukin-1β and BCL-2-associated X protein by ELISA or PCR or western blotting. The BMSCs therapy with IPC produced more surviving GFP-positive cells than the BMSCs therapy alone by fluorescent staining [at 70 h, (90 ± 14)/mm(2) vs. (61 ± 12)/mm(2), and at 28 days, (55 ± 14)/mm(2) vs. (26 ± 8)/mm(2), P<0.01, respectively]. At 28 days, it, when compared with the Control, IPC treatment, and BMSCs therapy, demonstrated higher left ventricular ejection fraction by echocardiography (62%± 8%, 69%± 6%, and 75%± 4% vs. 82%± 4%, P<0.05, respectively), higher expression of VEGF and bFGF by western blotting and PCR, less myocardial fibrosis by Massons trichrome staining, and higher capillary density by immunohistochemistry. These results suggest that ischemic postconditioning promotes the survival of transplanted cells and enhances their repair of infarcted myocardium through paracrine mechanisms.

Regulatory T cells contribute to rosuvastatin-induced cardioprotection against ischemia-reperfusion injury

ObjectivesCD4+CD25+ regulatory T cells (Tregs) play a key role in the prevention of various inflammatory and autoimmune disorders by suppressing immune responses. The beneficial effect of statins on myocardial ischemia-reperfusion injury (IRI) depends in part on their immunomodulatory and anti-inflammatory mechanisms. We aimed to determine whether Tregs contribute to statin-induced cardioprotection against myocardial IRI. MethodsThirty-two rats were divided into four groups: sham, ischemia-reperfusion (IR), rosuvastatin (RSV)/IR, and mevalonic acid (MVA)+RSV/IR. Myocardial IR was induced by a 30-min coronary occlusion, followed by a 48-h reperfusion. RSV (5 mg/kg) was administered intravenously 18 h before IR. The rats were killed after 48-h reperfusion. Serum cardiac troponin I (cTnI) was measured by ELISA, infiltration of inflammatory cells in myocardium by hematoxylin and eosin staining, expression of FoxP3 protein by western blotting, accumulation of Tregs in myocardium by immunohistochemical examination, and infarct size by TTC staining. ResultsSignificant elevation in serum cTnI, enlarged infarct size, and marked infiltration of inflammatory cells in myocardium were observed in the IR group. The administration of RSV significantly reduced the serum cTnI level, attenuated the accumulation of inflammatory cells, decreased infarct size, and increased the FoxP3 expression and Treg accumulation in myocardium compared with the IR group. The combination of RSV and MVA pretreatment partially abolished the anti-inflammatory and infarct size-limiting effects and completely reversed Treg accumulation in myocardium induced by RSV. The accumulation of inflammatory cells was negatively correlated with FoxP3 expression and Treg accumulation in the ischemic myocardium. ConclusionRSV pretreatment was associated with more Treg accumulation, less inflammatory response, and myocardial injury, suggesting that such cardioprotection against IRI was partially mediated by Treg-negative modulation of inflammation response, probably through the HMG-CoA reductase pathway.

Delayed versus immediate stenting for the treatment of ST-elevation acute myocardial infarction with a high thrombus burden.

ObjectivesHigh thrombus burden (HTB) is an independent predictor of no flow or low reflow during a primary percutaneous coronary intervention. This study aimed to compare immediate versus delayed stenting in ST-elevation myocardial infarction (STEMI) patients with HTB. MethodsIn this retrospective, nonrandomized study, a total of 103 consecutive STEMI patients with HTB (thrombus burden score, TBS≥3) were assigned to immediate stenting (IS group, n=50) or delayed stenting (DS group, n=53), a decision that was made at the discretion of the operators. The IS group received stent placement immediately, whereas the DS group was given enhanced antithrombotic therapies and deferred for stenting at least 7 days later. Thrombolysis in myocardial infarction (TIMI) flow score (TIMIs) and myocardial blush grade (MBG) were assessed angiographically and the left ventricular ejection fraction (LVEF) was measured echocardiographically. The major adverse cardiac event (MACE) was the composite of cardiac death, reinfarction, target vessel revascularization, heart failure, and major bleeding. ResultsThe DS group had better immediate MBG (P<0.001), higher LVEF at 6 months (P=0.044), and lower MACE rate at 1 year (log-rank P=0.008). Multiple logistic regression identified immediate stenting (odds ratio 7.4, 95% confidence interval 2.1–26.6; P=0.002) and high TBS (odds ratio 2.6, 95% confidence interval 1.1–6.5, P=0.034) as the independent predictors of poor myocardial perfusion. Delayed stenting benefited the male patients, those who were of a younger age, and those who had a larger infarction-related artery, higher TBS, or lower TIMIs in terms of MBG or MACE. Delayed stenting avoided stent implantation of the infarct-related artery in 12/53 (22.6%) patients particularly in the younger patients. ConclusionFor STEMI patients with HTB who have undergone initial thrombectomy, delayed stenting is safe and feasible, and may be associated with better immediate myocardial perfusion, more LV function recovery, and less occurrence of MACE at the 1-year follow-up.

Role of high‑mobility group box‑1 in myocardial ischemia/reperfusion injury and the effect of ethyl pyruvate

High-mobility group box-1 (HMGB1) acts as a proinflammatory cytokine that triggers and amplifies the inflammation cascade following ischemia/reperfusion (I/R). Ethyl pyruvate (EP) has been reported to inhibit HMGB1 release in several I/R models. This study was designed to investigate the potential role of HMGB1 in a rat myocardial I/R model and to determine the effect of EP. Male Sprague Dawley rats were subjected to 30 min myocardial ischemia and 48 h reperfusion. In protocol 1, the rats were assigned to one of four groups (n=16 per group): Phosphate-buffered saline (PBS) or recombinant human HMGB1 (rhHMGB1) at three different doses (1, 10 or 100 μg/kg). In protocol 2, the rats were also assigned to one of four groups (n=16 per group): Sham, control, EP and EP + rhHMGB1. EP (40 mg/kg) or rhHMGB1 (100 μg/kg) was injected intravenously prior to reperfusion. Hemodynamic measurements were performed, and myocardial infarct size (IS) was calculated. Western blotting was conducted to evaluate HMGB1, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) expression levels. In the protocol 1 rats, the IS was markedly increased in the rhHMGB1 (100 μg/kg) group compared with that in the PBS group, and this increase was accompanied by elevated levels of TNF-α and IL-6. In the protocol 2 rats, I/R resulted a 4.8-fold increase in HMGB1 expression with an increased IS and impaired cardiac function compared with the sham group. EP significantly inhibited the elevated HMGB1 level, suppressed the activated TNF-α and IL-6 and reduced cardiac dysfunction. This cardioprotection was abolished by rhHMGB1. In conclusion, accumulation of HMGB1 is deleterious to the heart following myocardial I/R. EP can exert a strong protective effect against myocardial I/R injury, and these benefits are associated with a reduction in HMGB1.

Circulating Soluble Lectin‐Like Oxidized Low‐Density Lipoprotein Receptor‐1 Levels Are Associated With Angiographic Coronary Lesion Complexity in Patients With Coronary Artery Disease

Angiographic coronary lesion complexity has been reported to predict plaque vulnerability. It is important to develop a noninvasive blood biomarker for accurate prognostication of angiographically complex lesions in patients with coronary artery disease (CAD).

Stem cells with FGF4-bFGF fused gene enhances the expression of bFGF and improves myocardial repair in rats.

The aim of this study was to investigate whether the modification of bone marrow-derived mesenchymal stem cells (BMSCs) with the fused FGF4 (fibroblast growth factor 4)-bFGF (basic fibroblast growth factor) gene could improve the expression and secretion of BFGF, and increase the efficacies in repairing infarcted myocardium. We used In-Fusion technique to construct recombinant lentiviral vectors containing the individual gene of bFGF, enhanced green fluorescent protein (EGFP), or genes of FGF4-bFGF and EGFP, and then transfected these lentiviruses into rat BMSCs. We conducted an in vitro experiment to compare the secretion of bFGF in BMSCs infected by these lentiviruses and also examined their therapeutic effects in the treatment of myocardial infraction in a rodent study. Sixty rats were tested in the following five conditions: Group-SHAM received only sham operation as controls; Group-AMI received only injection of placebo PBS buffer; Group-BMSC, Group-bFGF and Group-FGF4-bFGF received implantation of BMSCs with empty lentivirus, bFGF lentivirus, and FGF4-bFGF lentivirus, respectively. Our results found out that the transplanted FGF4-bFGF BMSCs had the highest survival rate, and also the highest myocardial expression of bFGF and microvascular density as evidenced by Western blotting and immunohistochemistry, respectively. As compared to other groups, the Group-FGF4-BFGF rats had the lowest myocardial fibrotic fraction, and the highest left ventricular ejection fraction. These results suggest that the modification of BMSCs with the FGF4-bFGF fused gene can not only increase the expression of bFGF but also improve its secretion. The FGF4-bFGF BMSCs thus can enhance the survival of the transplanted cells, diminish myocardial fibrosis, promote myocardial angiogenesis, and improve cardiac functions.

Elevated Human Endothelial Cell-Specific Molecule-1 Level and Its Association With Coronary Artery Disease in Patients With Hypertension

Background Endothelial dysfunction plays an important role in the pathophysiology of coronary artery disease (CAD). Previous studies suggested that human endothelial cell-specific molecule-1 (endocan) may be a novel endothelial dysfunction marker. This study aims to investigate the relationship between serum endocan level and the presence and severity of CAD in patients with hypertension. Methods A total of 190 eligible hypertension patients were enrolled in this study. Serum endocan level was measured by enzyme-linked immunosorbent assay. The presence and severity of CAD were evaluated by coronary angiography. Results Hypertensive patients with CAD had significantly higher serum endocan level than those without CAD (1.63 ± 0.51 ng/mL vs 1.31 ± 0.65 ng/mL, P < 0.05). Multivariate logistic regression revealed that serum endocan level was independently associated with the presence of CAD (odds ratio, 2.662; 95% confidence interval, 1.560–4.544; P < 0.001). Spearman rank correlation analysis demonstrated that serum endocan level was associated with SYNergy between PCI with TAXUS and Cardiac Surgery score (r = 0.349, P = 0.001). Conclusions Serum endocan level is independently correlated with the presence and severity of CAD in hypertension patients, and those with high endocan level may have an increased risk of developing atherosclerosis.