Lymphatic endothelial transcription factor Tbx1 promotes an immunosuppressive microenvironment to facilitate post-myocardial infarction repair.

The heart is an autoimmune-prone organ. It is crucial for the heart to keep injury-induced autoimmunity in check to avoid autoimmune-mediated inflammatory disease. However, little is known about how injury-induced autoimmunity is constrained in hearts. Here, we reveal an unknown intramyocardial immunosuppressive program driven by Tbx1, a DiGeorge syndrome disease gene that encodes a T-box transcription factor (TF). We found induced profound lymphangiogenic and immunomodulatory gene expression changes in lymphatic endothelial cells (LECs) after myocardial infarction (MI). The activated LECs penetrated the infarcted area and functioned as intramyocardial immune hubs to increase the numbers of tolerogenic dendritic cells (tDCs) and regulatory T (Treg) cells through the chemokine Ccl21 and integrin Icam1, thereby inhibiting the expansion of autoreactive CD8+ T cells and promoting reparative macrophage expansion to facilitate post-MI repair. Mimicking its timing and implementation may be an additional approach to treating autoimmunity-mediated cardiac diseases.

Sin1 (Stress-Activated Protein Kinase-Interacting Protein) Regulates Ischemia-Induced Microthrombosis Through Integrin αIIbß3-Mediated Outside-In Signaling and Hypoxia Responses in Platelets.

Objective- Microthrombosis as a serious consequence of myocardial infarction, impairs the microvascular environment and increases the occurrences of heart failure, arrhythmia, and death. Sin1 (stress-activated protein kinase-interacting protein) as an essential component of mTORC2 (mammalian target of rapamycin complex 2) is required for cell proliferation and metabolism in response to nutrients, stress, and reactive oxygen species and activates Akt and PKC (protein kinase C). However, the activation and function of Sin1/mTORC2 in ischemia-induced microthrombosis remain poorly understood. Approach and Results- The phosphorylation of the mTORC2 target Akt at S473 (serine 473) was significantly elevated in platelets from the distal end of left anterior descending obstructions from patients who underwent off-pump coronary artery bypass grafting compared with platelets from healthy subjects. Consistent with this finding, phosphorylation of T86 in Sin1 was also dramatically increased. Importantly, the augmented levels of phosphorylated Sin1 and Akt in platelets from 61 preoperative patients with ST-segment-elevation myocardial infarction correlated well with the no-reflow phenomena observed after revascularization. Platelet-specific Sin1 deficiency mice and Sin1 T86 phosphorylation deficiency mice were established to explore the underlying mechanisms in platelet activation. Mechanistically, Sin1 T86 phosphorylation amplifies mTORC2-mediated downstream signals; it is also required for αIIbß3-mediated outside-in signaling and plays a role in generating hypoxia/reactive oxygen species through NAD+/Sirt3 (sirtuin 3)/SOD2 (superoxide dismutase 2) pathway. Importantly, Sin1 deletion in platelets protected mice from ischemia-induced microvascular embolization and subsequent heart dysfunction in a mouse model of myocardial infarction. Conclusions- Together, the results of our study reveal a novel role for Sin1 in platelet activation. Thus, Sin1 may be a valuable therapeutic target for interventions for ischemia-induced myocardial infarction deterioration.

Treatment of renal cell carcinoma with a level III or level IV inferior vena cava thrombus using cardiopulmonary bypass and deep hypothermic circulatory arrest.

BACKGROUND: The aim of this study was to investigate the minimally invasive cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA) approach in the management of renal cell carcinoma (RCC) with level III or IV inferior vena cava (IVC) thrombus and evaluate the survival outcomes. METHODS: We performed a retrospective analysis on 32 RCC patients with IVC thrombus that underwent nephrectomy and thrombectomy via the minimally invasive CPB/DHCA approach between January 2007 and December 2013. Perioperative variables (for example, operative time, CPB duration, and circulatory arrest duration), estimated blood loss, hospital stay, perioperative complications, and survival data were recorded and analyzed. RESULTS: Thirty-two patients (median age: 56 years) were treated surgically using the CPB and DHCA approach for RCC with a level III (n=25) or level IV (n=7) tumor thrombus. The median operation time was 360 min (interquartile range (IQR): 300 to 435 min) with median CPB and DHCA durations of 149 min and 23 min, respectively. The median estimated blood loss was 2,500 ml. Four complications were observed but no deaths occurred perioperatively. The median follow-up was 25 months (range: 4 to 64 months). The mean overall survival (OS) was 28.2±4.6 months while the disease-free survival (DFS) was 19.5±11.6 months. In patients with M0 disease, ten patients developed metastases and were treated with sorafenib as an adjuvant therapy. The mean OS and DFS of this subgroup were 25.4±12.8 months and 16.0±14.2 months, respectively. CONCLUSIONS: Radical nephrectomy and thrombectomy using CPB and DHCA to treat RCC is a relatively safe approach associated with low morbidity and mortality. This minimally invasive procedure may help minimize surgical trauma and improve perioperative outcomes.

The use of statins to prevent postoperative atrial fibrillation after coronary artery bypass grafting: a meta-analysis of 12 studies.

There is no agreement on whether statins influence the incidence of atrial fibrillation after coronary artery bypass grafting. We performed a meta-analysis of 12 studies that compared statins with controls. Statin therapy significantly reduced the incidence of postoperative atrial fibrillation (POAF) (odds ratio, 0.50; 95% confidence interval, 0.35-0.73) and length of hospital stay (weighted mean difference, -0.72; 95% confidence interval, -0.99 to -0.45), an effect that survived detailed subgroup analysis. Meta-regression analysis revealed that patient characteristics did not influence the extent of improvement in the incidence of POAF attributable to statins. In conclusion, patients undergoing coronary artery bypass grafting benefit from perioperative treatment with statins, which significantly reduce the incidence of POAF and length of hospital stay.

PFKM inhibits doxorubicin-induced cardiotoxicity by enhancing oxidative phosphorylation and glycolysis.

Heart failure (HF) is a global pandemic which affects about 26 million people. PFKM (Phosphofructokinase, Muscle), catalyzing the phosphorylation of fructose-6-phosphate, plays a very important role in cardiovascular diseases. However, the effect of PFKM in glycolysis and HF remains to be elucidated. H9c2 rat cardiomyocyte cells were treated with doxorubicin (DOX) to establish injury models, and the cell viability, apoptosis and glycolysis were measured. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) and immunoblotting were used for gene expression. DOX treatment significantly inhibited PFKM expression in H9c2 cells. Overexpression of PFKM inhibited DOX-induced cell apoptosis and DOX-decreased glycolysis and oxidative phosphorylation (OXPHOS), while silencing PFKM promoted cell apoptosis and inhibited glycolysis and OXPHOS in H9c2 cells. Moreover, PFKM regulated DOX-mediated cell viability and apoptosis through glycolysis pathway. Mechanism study showed that histone deacetylase 1 (HDAC1) inhibited H3K27ac-induced transcription of PFKM in DOX-treated cells and regulated glycolysis. PFKM could inhibit DOX-induced cardiotoxicity by enhancing OXPHOS and glycolysis, which might benefit us in developing novel therapeutics for prevention or treatment of HF.

Wdpcp promotes epicardial EMT and epicardium-derived cell migration to facilitate coronary artery remodeling.

During coronary vasculature development, endothelial cells enclose the embryonic heart to form the primitive coronary plexus. This structure is remodeled upon recruitment of epicardial cells that may undergo epithelial-mesenchymal transition (EMT) to enable migration and that give rise to smooth muscle cells. In mice expressing a loss-of-function mutant form of Wdpcp, a gene involved in ciliogenesis, the enclosure of the surface of the heart by the subepicardial coronary plexus was accelerated because of enhanced chemotactic responses to Shh. Coronary arteries, but not coronary veins in Wdpcp mutant mice, showed reduced smooth muscle cell coverage. In addition, Wdpcp mutant hearts had reduced expression of EMT and mesenchymal markers and had fewer epicardium-derived cells (EPDCs) that showed impaired migration. Epicardium-specific deletion of Wdpcp recapitulated the coronary artery defect of the Wdpcp mutant. Thus, Wdpcp promotes epithelial EMT and EPDC migration, processes that are required for remodeling of the coronary primitive plexus. The Wdpcp mutant mice will be a useful tool to dissect the molecular mechanisms that govern the remodeling of the primitive plexus during coronary development.

Gax regulates human vascular smooth muscle cell phenotypic modulation and vascular remodeling.

Abnormal phenotypic modulation of vascular smooth muscle cells (VSMCs) is a hallmark of cardiovascular diseases such as atherosclerosis, hypertension and restenosis after angioplasty. Transcription factors have emerged as critical regulators for VSMCs function, and recently we verified inhibiting transcription factor Gax was important for controlling VSMCs proliferation and migration. This study aimed to determine its role in phenotypic modulation of VSMCs. Western blot revealed that overexpression of Gax increased expression of VSMCs differentiation marker genes such as calponin and SM-MHC 11. Then, Gax overexpression potently suppressed proliferation and migration of VSMCs with or without platelet-derived growth factor-induced-BB (PDGF-BB) stimuli whereas Gax silencing inhibited these processes. Furthermore, cDNA array analysis indicated that Rap1A gene was the downstream target of Gax in human VSMCs. And overexpression of Gax significantly inhibited expression of Rap1A in VSMCs with or without PDGF-BB stimuli. Moreover, overexpression of Rap1A decreased expression of VSMCs differentiation marker genes and increased proliferation and migration of VSMCs with or without PDGF-BB stimuli. Finally, Gax overexpression significantly inhibited the neointimal formation in carotid artery injury of mouse models, specifically through maintaining VSMCs contractile phenotype by decreasing Rap1A expression. In conclusion, these results indicated that Gax was a regulator of human VSMCs phenotypic modulation by targeting Rap1A gene, which suggested that targeting Gax or its downstream targets in human VSMCs may provide an attractive approach for the prevention and treatment of cardiovascular diseases.

Midterm results of "treat and repair" for adults with non-restrictive ventricular septal defect and severe pulmonary hypertension.

BACKGROUND: A non-restrictive ventricular septal defect (VSD) can cause intracardiac left to right shunt, which leads to increased pulmonary vascular resistance (PVR) and pulmonary hypertension causes bi-directional or even right-left shunt, namely the Eisenmenger's syndrome. For patients with non-restrictive VSD with severe pulmonary hypertension at stage of near or to be Eisenmenger's syndrome, traditional VSD repair carries high mortality and poor prognosis. Recently, targeted drug therapy was used to decrease pulmonary circulation resistance in these patients before they receive defect repair surgery, namely "treat and repair" strategy, however, there is few reports about the midterm result of this strategy in adults with non-restrictive VSD with severe pulmonary hypertension at stage of near or to be Eisenmenger's syndrome. METHODS: In this study, we used this strategy to treat 41 adult VSD patients who received bosentan as the targeted therapy to decrease their PVR before and after repair surgery. RESULTS: A total of 39 patients were followed up for an average of 37 months. None of the patients died during follow-up. Among them, 36 cases continued targeted drug therapy, whose mean pulmonary artery pressure (mPAP) was significantly reduced, including 31 cases with mPAP <50 mmHg, and the valve of tap hole was closed. Besides, the SpO2 was significantly elevated. CONCLUSIONS: These results demonstrated that "treat-and-repair" strategy may be a viable approach for the adults with non-restrictive VSD with severe pulmonary hypertension at stage of near or to be Eisenmenger's syndrome.

Identification and characterization of CD4(+)AT2(+) T lymphocyte population in human thoracic aortic aneurysm.

Thoracic aortic aneurysm (TAA) is progressive fatal aortic pathological dilation. However, the underlying molecular mechanisms are still largely unknown. Evidences suggest that endothelial cells and renin-angiotensin system may participate in the pathogenesis of TAA. This study aimed to investigate whether angiotensin II type 2 receptor (AT2) positive cells are involved in TAA formation. The mRNA level of AT2 is dramatically elevated in TAA compared with in controls. CD4(+)AT2(+) cells increased in both aortic wall and circulation of TAA patients. The levels of IL-1ß and IL-17B in CD4(+)AT2(+) cells were lower than those in CD4(+)AT2(-) cells. When compared with endothelial cells (ECs) cultured alone, CD4(+)AT2(+) cells showed an inhibitory effect on proliferation and MMP2 expression in ECs, but CD4(+)AT2(-) cells promoted proliferation and MMP2 expression in ECs. Both CD4(+)AT2(+) and CD4(+)AT2(-) cells suppressed apoptosis of ECs. In conclusion, we have identified a novel population of CD4(+)AT2(+) T lymphocytes that show protective effect in TAA through inhibition of growth, apoptosis, and MMP2 expression in ECs.

Direct reprogramming of human fibroblasts to functional and expandable hepatocytes.

The generation of large numbers of functional human hepatocytes for cell-based approaches to liver disease is an important and unmet goal. Direct reprogramming of fibroblasts to hepatic lineages could offer a solution to this problem but so far has only been achieved with mouse cells. Here, we generated human induced hepatocytes (hiHeps) from fibroblasts by lentiviral expression of FOXA3, HNF1A, and HNF4A. hiHeps express hepatic gene programs, can be expanded in vitro, and display functions characteristic of mature hepatocytes, including cytochrome P450 enzyme activity and biliary drug clearance. Upon transplantation into mice with concanavalin-A-induced acute liver failure and fatal metabolic liver disease due to fumarylacetoacetate dehydrolase (Fah) deficiency, hiHeps restore the liver function and prolong survival. Collectively, our results demonstrate successful lineage conversion of nonhepatic human cells into mature hepatocytes with potential for biomedical and pharmaceutical applications.

Meta-analysis of clinical studies comparing coronary artery bypass grafting with percutaneous coronary intervention in patients with end-stage renal disease.

End-stage renal disease (ESRD) patients are at high risk for coronary artery disease (CAD). The optimal revascularization strategy remains unknown. We performed a meta-analysis of retrospective observational trials to compare coronary artery bypass grafting (CABG) with percutaneous coronary intervention (PCI) for ESRD patients with CAD. A search of published reports was conducted to identify clinical studies comparing CABG with PCI in ESRD patients with CAD with a minimal follow-up of 12 months. Sixteen studies included 32 350 ESRD patients with revascularization. Compared with PCI, CABG was associated with a lower risk for late mortality [relative risk (RR) 0.90, 95% confidence interval (CI) 0.87-0.93], myocardial infarction event (RR 0.64, 95% CI: 0.61-0.68), repeat revascularization event (RR 0.22, 95% CI: 0.16-0.31) and cumulative events (RR 0.69, 95% CI: 0.65-0.73), despite having a higher risk for early mortality (RR 1.98, 95% CI: 1.51-2.60). In conclusion, the long-term results of PCI in ESRD patients are dismal, and CABG is significantly superior to PCI in this subset of patients.

[Effects on proliferation and apoptosis of serum-induced rabbit VSMCs by adenovirus-mediated transfer of the Gax gene].

AIM: To investigate the effect of a recombinant replication-incompetent Ad5-hGax vector on the proliferation and apoptosis of serum-induced rabbit vascular smooth muscle cells (VSMCs) in vitro, and to provide an important support that Gax would be an optimal gene for gene therapy in vein graft failure. METHODS: The Ad5-hGax vector was infected into rabbit VSMCs, then the protein level of rabbit VSMCs was detected at 1 d, 3 d, 5 d by Western blot, respectively. MTT was applied to observe the inhibitory effects of overexpressed hGax on serum-induced rabbit VSMCs. the apoptosis of serum-induced rabbit VSMCs was measured by using flow cytometry in 72 h after transfection. RESULTS: The protein expression of human Gax in the Ad5-hGax transfected cells on 1st day, 3rd day, 5th day was determined; MTT showed that the proliferation of serum-induced rabbit VSMCs was significantly inhibited in Ad5-hGax group at 48 h, 72 h and 96 h (P<0.05, respectively); After transfecting for 72 h, flow cytometry analysis showed that the number of the apoptosis cells was increased in serum-induced Rabbit VSMCs of Ad5-hGax group (P<0.05). CONCLUSION: Overexpressed hGax could inhibit the proliferation of serum-induced Rabbit VSMCs and induce their apoptosis. These findings carry significant implications for adenovirus vector-based Gax gene therapies for vein graft failure.

[Effects of acupuncture-drug compound anesthesia on perioperative inflammatory factors in patients undergoing cardiac surgery].

OBJECTIVE: To explore the effect of acupuncture-drug compound anesthesia on immune function in patients with extracorporeal circulation undergoing cardiac surgery. METHODS: Thirty cases undergoing cardiac surgery which included atrial septal defect neoplasty, ventricular septal defect neoplasty, mitral valve replacement and pulmonary valve coarctotomy were randomly divided into group A and group B, 15 cases in each group. Group A was given general anesthesia plus acupuncture at Neiguan (PC 6), Lieque (LU 7) and Yunmen (LU 2), and group B was given simple general anesthesia. Tumor necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2) and interleukin-10 (IL-10) levels before and after surgery were compared. RESULTS: The level of TNF-alpha was increased and the levels of IL-2 and IL-10 in the serum were decreased in both groups after extracorporeal circulation for 2 h and 24 h, and the ranges of all changes were more less in group A (all P < 0.05). CONCLUSION: Compared with simple general anesthesia, acupuncture-drug compound anesthesia can improve immune suppression partially in the perioperative periods under the same conditions of controlling anesthesia degree.