Radiomics-Based Risk Assessment Correlates With Outcomes in Patients With Acute Type B Aortic Dissection Undergoing Thoracic Endovascular Repair.

OBJECTIVES: Our study aimed to investigate the correlations between radiomics-based assessment and outcomes, including positive aortic remodeling (PAR), reintervention for dissection at 1 year, and overall survival, in patients with Type B aortic dissection (TBAD) who underwent thoracic endovascular aortic repair (TEVAR). METHODS: This was a single-center, retrospective, cohort study. The cohort comprised 104 patients who had undergone TEVAR of TBAD in our institution between January 2010 and October 2022. We segmented preoperative computed tomography (CT) images of the patients' descending aorta regions, then extracted a comprehensive set of radiomic features, including first-order features, shape features (2D and 3D), gray-level co-occurrence matrix (GLCM), gray-level size zone matrix, gray-level run length matrix, gray-level dependence matrix, neighborhood gray-tone difference matrix, from the regions of interest. Next, we selected radiomics features associated with total descending aorta positive aortic remodeling (TDA-PAR) and reintervention by least absolute shrinkage and selection operator (LASSO) regression and features associated with survival by LASSO-Cox regression. This enabled us to calculate radiomics-based risk scores for each patient. We then allocated the patients to high and low radiomics-based risk groups, the cutoff being the median score. We used 3 different models to validate the radiomics-based risk scores. RESULTS: The patients' baseline characteristics did not differ between those who achieved TDA-PAR and those who did not. The radiomics-based risk scores were significantly and independently associated with all 3 outcomes. As to the impact of specific radiomics features, we found that GLSZM_SmallAreaLowGrayLevelEmphasis and shape_Maximum2DDiameterColumn had positive impacts on both reintervention and survival outcomes, whereas GLCM_Idmn positively affected survival but negatively affected reintervention. We found that radiomics-based risk for TDA-PAR correlated most significantly with zone 6 PAR. CONCLUSIONS: Radiomics-based risk scores were significantly associated with the outcomes of TDA-PAR, reintervention, and overall survival. Radiomics has the potential to make significant contributions to prediction of outcomes in patients with TBAD undergoing TEVAR. CLINICAL IMPACT: In this study of 104 patients with Type B aortic dissection, we demonstrated associations between radiomics-based risk and postoperative outcomes, including total descending aorta positive aortic remodeling, reintervention and survival. These findings highlight radiomics' potential as a tool for risk stratification and prognostication in acute Type B aortic dissection management.

STOP-Bang Questionnaire Is Associated With Aortic Remodeling in Patients With Acute Type B Aortic Dissection Undergoing Standard Thoracic Endovascular Aortic Repair.

PURPOSE: To determine whether the STOP-Bang questionnaire, which is a tool for evaluating obstructive sleep apnea, is associated with aortic remodeling after thoracic endovascular aortic repair (TEVAR) in patients with type B aortic dissection (TBAD). METHODS: Patients with TBAD who underwent standard TEVAR at our center from January 2015 to December 2020 were enrolled. For the included patients, we recorded baseline characteristics, comorbidities, preoperative computed tomographic angiography findings, procedure details, and complications. The STOP-Bang questionnaire was administered to each patient. Total scores comprised points for 4 yes/no questions and 4 clinical measurements. STOP-Bang ≥5 and STOP-Bang <5 groups were then created using the STOP-Bang total scores. We evaluated aortic remodeling 1 year after discharge and the reintervention rate, as well as false lumen complete thrombosis (FLCT) and non-FLCT length. RESULTS: Fifty-five patients were enrolled in the study; STOP-Bang <5, n=36, and STOP-Bang ≥5, n=19. Compared with the STOP-Bang ≥5 group, the STOP-Bang <5 group achieved statistically significantly higher descending aorta positive aortic remodeling (PAR) rates in zones 3 to 5 (zone 3: p=0.002; zone 4: p=0.039; zone 5: p=0.023), higher total descending aorta-PAR rate (66.7% vs 36.8%, respectively; p=0.004), and lower reintervention rate (8.1% vs 38.9%, respectively; p=0.005). In the logistic regression analysis, STOP-Bang ≥5 had an odds ratio of 0.12 (95% confidence interval: 0.03-0.58; p=0.008). There was no significant difference in overall survival between the groups. CONCLUSION: STOP-Bang questionnaire scores were associated with aortic remodeling after TEVAR in patients with TBAD. Increasing the frequency of surveillance after TEVAR might be beneficial in these patients. CLINICAL IMPACT: We analysed aortic remodelling 1 year after thoracic endovascular aortic repair (TEVAR) in acute type B aortic dissection (TBAD) patients with STOP-Bang < 5 and STOP-Bang ≥ 5. Aortic remodelling was better, and the reintervention rate was higher in patients with STOP-Bang < 5 compared with patients with STOP-Bang ≥ 5. In patients with STOP-Bang ≥ 5, aortic remodelling was worse in zones 3-5 compared with zones 6-9. This study suggests that the STOP-Bang questionnaire results is associated with aortic remodelling after TEVAR in patients with TBAD.

The Relationship Between the Global Limb Anatomic Staging System Inframalleolar Modifier and the Outcomes of Diabetic Foot Ulcer with Peripheral Artery Disease.

BACKGROUND: We aimed to investigate the relationship between the condition of the inframalleolar (IM) arteries, as assessed by the Global Limb Anatomic Staging System Inframalleolar (GLASS IM) modifier, and the outcomes of patients with diabetic foot ulcers. METHODS: The data of 215 patients, who underwent endovascular therapy from January 2016 to May 2020 at our center, were retrospectively reviewed. Patients were divided into the P0, P1, and P2 groups according to the angiography results. The rates of ulcer healing, limb salvage, survival, and amputation-free survival were compared during the 2-year period after discharge. RESULTS: Of the 216 affected limbs, 35 (16%) were classed as P0, 122 (57%) as P1, and 59 (27%) as P2. Compared with the P2 group, the P0 + P1 group had a higher ulcer healing rate (P = 0.001), a shorter ulcer healing time (P = 0.004), and a higher survival rate (P = 0.044). GLASS IM Modifier classification P2 was an independent predictor of nonhealing ulcers. No significant difference was observed between the P0 versus P1 groups. CONCLUSIONS: GLASS IM modifier classification P2 is an independent risk factor for a poor outcome. GLASS IM modifier classification P0 versus P1 demonstrates similar outcomes to each other.

Activation of the CaR-CSE/H2S pathway confers cardioprotection against ischemia-reperfusion injury.

Ischemia-reperfusion (I/R) injury is a multifactorial process triggered when an organ is subjected to transiently reduced blood supply. The result is a cascade of pathological complications and organ damage due to the production of reactive oxygen species following reperfusion. The present study aims to evaluate the role of activated calcium-sensing receptor (CaR)-cystathionine γ-lyase (CSE)/hydrogen sulfide (H2S) pathway in I/R injury. Firstly, an I/R rat model with CSE knockout was constructed. Transthoracic echocardiography, TTC and HE staining were performed to determine the cardiac function of rats following I/R Injury, followed by TUNEL staining observation on apoptosis. Besides, with the attempt to better elucidate how CaR-CSE/H2S affects I/R, in-vitro culture of human coronary artery endothelial cells (HCAECs) was conducted with gadolinium chloride (GdCl3, a CaR agonist), H2O2, siRNA against CSE (siCSE), or W7 (a CaM inhibitor). The interaction between CSE and CaM was subsequently detected. Plasma oxidative stress indexes, H2S and CSE, and apoptosis-related proteins were all analyzed following cell apoptosis. We found that H2S elevation led to the improvement whereas CSE knockdown decreased cardiac function in rats with I/R injury. Moreover, oxidative stress injury in I/R rats with CSE knockout was aggravated, while the increased expression of H2S and CSE in the aortic tissues resulted in alleviated the oxidative stress injury. Moreover, increased H2S and CSE levels were found to inhibit cell apoptotic ability in the aortic tissues after I/R injury, thus attenuating oxidative stress injury, accompanied by inhibited expression of apoptosis-related proteins. In HCAECs following oxidative stress treatment, siCSE and CaM inhibitor were observed to reverse the protection of CaR agonist. Coimmunoprecipitation assay revealed the interaction between CSE and CaM. Taken together, all above-mentioned data provides evidence that activation of the CaR-CSE/H2S pathway may confer a potent protective effect in cardiac I/R injury.

Gut microbe-derived metabolite trimethylamine N-oxide induces cardiac hypertrophy and fibrosis.

Trimethylamine N-oxide (TMAO), a gut microbe-derived metabolite of dietary choline and other trimethylamine-containing nutrients, has been linked to increased cardiovascular disease risk. It is unknown whether TMAO plays a role in the development of cardiac hypertrophy. Transverse aortic constriction (TAC) was performed to induce cardiac hypertrophy in Sprague-Dawley (SD) rats. We observed that TMAO levels were significantly elevated in SD rats after 6 weeks of TAC, suggesting the potential role of TMAO in regulating cardiac hypertrophy. In cultured cardiomyocytes, TMAO treatment stimulated cardiac hypertrophy, as indicated by increased cell area of cardiomyocytes and expression of hypertrophic markers including atrial natriuretic peptide (ANP) and beta-myosin heavy chain (ß-MHC). Additionally, TMAO treatment induced cardiac hypertrophy and cardiac fibrosis in SD rats. Reducing TMAO synthesis by antibiotics (Abs) attenuated TAC-induced cardiac hypertrophy and fibrosis. Furthermore, pharmacological inhibition of Smad3 by SIS3 significantly reduced the expression of ANP and ß-MHC, and cardiomyocyte cell size in TMAO-treated group. These data for the first time demonstrate that gut microbe-derived metabolite TMAO induces cardiac hypertrophy and fibrosis involving Smad3 signaling, suggesting that inhibition of gut microbes or generation of TMAO may become a potential target for the prevention and treatment of cardiac hypertrophy.

A Promising Therapeutic Target for Metabolic Diseases: Neuropeptide Y Receptors in Humans.

Human neuropeptide Y (hNPY) is one of the most widely expressed neurotransmitters in the human central and peripheral nervous systems. It consists of 36 highly conserved amino acid residues, and was first isolated from the porcine hypothalamus in 1982. While it is the most recently discovered member of the pancreatic polypeptide family (which includes neuropeptide Y, gut-derived hormone peptide YY, and pancreatic polypeptide), NPY is the most abundant peptide found in the mammalian brain. In order to exert particular functions, NPY needs to bind to the NPY receptor to activate specific signaling pathways. NPY receptors belong to the class A or rhodopsin-like G-protein coupled receptor (GPCR) family and signal via cell-surface receptors. By binding to GPCRs, NPY plays a crucial role in various biological processes, including cortical excitability, stress response, food intake, circadian rhythms, and cardiovascular function. Abnormal regulation of NPY is involved in the development of a wide range of diseases, including obesity, hypertension, atherosclerosis, epilepsy, metabolic disorders, and many cancers. Thus far, five receptors have been cloned from mammals (Y1, Y2, Y4, Y5, and y6), but only four of these (hY1, hY2, hY4, and hY5) are functional in humans. In this review, we summarize the structural characteristics of human NPY receptors and their role in metabolic diseases.

Resveratrol Ameliorates Cardiac Dysfunction by Inhibiting Apoptosis via the PI3K/Akt/FoxO3a Pathway in a Rat Model of Diabetic Cardiomyopathy.

The aim of this study was to explore the effect and mechanism of action of resveratrol (RSV) on cardiac function in diabetic cardiomyopathy (DCM). Hyperglycemia-induced apoptosis contributes to the pathogenic changes in DCM. RSV treatment inhibited high glucose-induced apoptosis of neonatal rat ventricular myocytes. Additionally, high glucose decreased cell viability, prevented serine-threonine kinase (Akt) and FoxO3a phosphorylation, and suppressed cytoplasmic translocation of FoxO3a. However, these effects of apoptosis were reversed by 10 µM of RSV. The PI3K inhibitor LY294002 abolished the RSV protective effect in vitro. RSV (5 or 50 mg·kg·d orally for 8 weeks) prevented the deterioration of cardiac function and structural cardiomyopathy in a streptozotocin-induced rat model of diabetes and reduced apoptosis in diabetic myocardium. Furthermore, it restored streptozotocin-impaired phosphorylation of Akt and FoxO3a (p-Akt and p-FoxO3a) and suppressed nuclear translocation of FoxO3a in vivo. Together, these data indicate that RSV has therapeutic potential against DCM by inhibiting apoptosis via the PI3K/Akt/FoxO3a pathway.

Puerarin prevents cardiac hypertrophy induced by pressure overload through activation of autophagy.

This study aimed to explore the effects of puerarin on autophagy in cardiac hypertrophy. Decreased 5'-adenosine monophosphate kinase (AMPK) activity alone with inhibited autophagy could be detected in rats within 3 weeks after aortic banding (AB). Puerarin treatment for 3 weeks in AB rats significantly restored autophagy. Administration of puerarin for 6 weeks effectively restricted cardiomyocyte hypertrophy and apoptosis. In an in vitro study, similar anti-hypertrophy and anti-apoptosis effects of puerarin on isoprenaline-induced H9c2 cells were also observed. After inhibition of autophagy by pretreatment with 3-methyladenine, the protective effects of puerarin were blocked. Further in vivo study demonstrated that puerarin significantly enabled phosphorylation of 5'-AMPK to be activated, subsequently inhibiting expression of the mammalian target of rapamycin (mTOR) target proteins S6 ribosomal protein and 4E-binding protein 1. All these data indicate that puerarin exerts protective effects against cardiomyocyte hypertrophy and apoptosis, partly by restoration of autophagy through AMPK/mTOR-mediated signaling.

Resveratrol ameliorates cardiac dysfunction induced by pressure overload in rats via structural protection and modulation of Ca(2+) cycling proteins.

BACKGROUND: Cardiac hypertrophy is a compensatory stage of the heart in response to stress such as pressure overload (PO), which can develop into heart failure (HF) if left untreated. Resveratrol has been reported to prevent the development of hypertrophy and contractile dysfunction induced by PO. However, other studies found that resveratrol treatment for a longer period of time failed to regress cardiac hypertrophy. The aim of this study is to determine the timing of resveratrol treatment to achieve antihypertrophic effect and investigate whether resveratrol prevents the development of HF through preservation of myocardium structure and modulation of Ca(2+) handling proteins. METHODS: To generate rats with cardiac hypertrophy, male Sprague-Dawley rats were subjected to PO (aortic banding procedure) for 4 weeks. Sham-operated animals served as controls. Rats with cardiac hypertrophy were given resveratrol (4 mg/kg/day) for 4, 6, and 8 weeks, respectively. Histological and echocardiographic analysis and transmission electron microscopy were performed to assess cardiac structure and function. The levels of Ca(2+) handling proteins were measured by western blot analysis. RESULTS: Histological analysis showed that resveratrol treatment regressed developed cardiac hypertrophy at 8 and 10 weeks postsurgery, but not at 12 weeks. However, resveratrol strongly and continuously prevented the development of cardiac dysfunction and dilation of cardiac chamber as evaluated by echocardiography and H&E staining of heart cross-sections. In addition, PO-induced cardiac fibrosis was completely inhibited by resveratrol treatment. Resveratrol markedly prevented the disrupted myocardium but partially rescued mitochondrial abnormality in banded rats. Moreover, resveratrol prevented the alteration of Ca(2+) handling proteins induced by aortic banding, including downregulation of sarcoplasmic reticulum Ca(2+) ATPase 2 (SERCA2) and ryanodine receptor 2 (RyR2), hypophosphorylated phospholamban (PLB), upregulation of Na(+)/Ca(2+)-exchangers (NCX1) and increased expression and phosphorylation of Ca(2+)/calmodulin -dependent protein kinase II (CaMKII). Moreover, resveratrol alleviated the decreased SERCA activity induced by aortic banding. CONCLUSIONS: Resveratrol effectively prevented the transition from compensatory to decompensatory stage of cardiac hypertrophy induced by PO, but this effect is dependent on the timing of treatment. We suggest that resveratrol may exert beneficial effects on cardiac hypertrophy through protection of cardiac structure and modulation of Ca(2+) handling proteins.

Peptide-Amphiphilic Nanoassemblies as a Responsive Senolytic Navigator for Targeted Removal of Senescent Cardiomyocytes to Ameliorate Heart Failure.

Heart failure (HF) represents the terminal stage of numerous cardiovascular disorders and lacks effective therapeutic strategies. The accumulation of senescent cardiomyocytes is a cardinal characteristic of HF, contributing to myocardial dysfunction and deteriorating the myocardial microenvironment through the development of senescence-associated secretory phenotypes (SASPs), ultimately culminating in pathological remodeling. Senolytics, a promising therapeutic strategy that selectively induces apoptosis in senescent cells, faces challenges due to nonspecific effects, raising concerns for clinical implementation. In this study, we developed peptide-amphiphilic nanoassemblies as responsive drug navigators for targeted delivery. The modular nanoassemblies comprise a hydrophilic domain containing a CD9-binding peptide, a hydrophobic domain incorporating a reactive oxygen species (ROS)-responsive motif, and an alkyl tail for encapsulation of the senolytic ABT263. The CD9-targeted and ROS-responsive nanoassemblies (AP@ABT263) specifically recognized senescent cardiomyocytes and modulated the release of ABT263 in the presence of elevated intracellular ROS levels. AP@ABT263 treatment significantly enhanced the targeted delivery of ABT263 to senescent cells in both in vitro and in vivo while showing minimal toxicity to normal cardiomyocytes and other tissues. Our findings provide compelling evidence that AP@ABT263 efficiently eradicated senescent cardiomyocytes, enhanced cardiac function, and attenuated the deleterious effects of SASP, thereby preventing adverse cardiac remodeling. In summary, AP@ABT263 represents a highly promising approach for responsive and controlled drug release in senescent cardiomyocytes, providing valuable insights into the development of intelligent pharmaceutical interventions for the management of HF.

Association of spironolactone treatment and arterial stiffness and cardiovascular disease in hypertensive patients.

Introduction: The aim of the current study was to evaluate the association of spironolactone and arterial stiffness and composite cardiovascular disease (CVD, including coronary heart disease, congestive heart failure and ischemic stroke) in hypertensive patients. Material and methods: Baseline data were collected and arterial stiffness was presented by carotid-femoral pulse wave velocity (cf-PWV) using applanation tonometry. Serum levels of fasting plasma glucose, total cholesterol, C-reactive protein and creatinine were measured using an automatic biochemistry analyzer. Plasma aldosterone concentration and plasma renin activity were determined by radioimmunoassay. The associations of spironolactone and arterial stiffness and composite CVD were evaluated. Results: Compared to patients without spironolactone (n = 274), those with spironolactone (n = 170) were older and more likely to have diabetes and chronic heart failure. No differences in antihypertensive medications used were observed except for spironolactone. Mean number of antihypertensive medications used was significantly higher in the spironolactone group (2.6 ±0.8 vs. 2.2 ±0.6). Compared to patients without spironolactone, those with spironolactone had significantly lower cf-PWV (9.4 ±1.8 vs. 10.1 ±2.2 m/s). After adjustment for covariates, spironolactone was still associated with 10% lower risk of arterial stiffness, with a 95% confidence interval (CI) of 0.85-0.97. In patients without arterial stiffness, after adjustment for covariates, no significant association of spironolactone and composite CVD was observed. However, in patients with increased arterial stiffness, after adjustment for covariates, spironolactone was still independently associated with 11% lower risk of composite CVD (95% CI: 0.83-0.97). Conclusions: Spironolactone treatment is independently associated with lower cf-PWV and lower prevalence of composite CVD in patients with increased arterial stiffness.

Association of anti-hyperuricemia treatment and prevalent cardiovascular disease in hypertensive patients.

INTRODUCTION: The current study aimed to evaluate the association of anti-hyperuricemia treatment and prevalent cardiovascular disease (CVD) in hypertensive patients. MATERIAL AND METHODS: Primary hypertensive patients with hyperuricemia were enrolled. All participants were separated into two groups: anti-hyperuricemia and control groups (without anti-hyperuricemia treatment). Comparisons of prevalent CVD including coronary heart disease, ischemic stroke and heart failure were made and the associations of anti-hyperuricemia treatment and prevalent CVD were analyzed. RESULTS: Compared to the anti-hyperuricemia group, patients in the control group had significantly higher serum C-reactive protein (10.6 ±2.8 vs. 7.4 ±1.2 mg/dl) and uric acid (UA) levels (438 ±33 vs. 379 ±64 µmol/l), and were more likely to receive ß-blockers (34.2% vs. 31.1%) and calcium channel blockers (49.2% vs. 43.4%). The prevalence of ischemic stroke was higher in the control group (15.8% vs. 11.3%). Compared to other groups, blood pressure was significantly higher in patients in the 4th quartile serum UA level group. In the unadjusted model, anti-hyperuricemia treatment was significantly associated with a reduced odds ratio (OR) of composite CVD. After adjusting for potential covariates, OR of anti-hyperuricemia treatment for composite CVD was 0.89 with a 95% confidence interval (IC) of 0.82-0.98. Associations of anti-hyperuricemia treatment and ischemic stroke were also significant with OR = 0.93 and 95% CI: 0.88-0.99, while associations of anti-hyperuricemia with coronary heart disease and heart failure attenuated into insignificance after adjusting for covariates. CONCLUSIONS: In hypertensive patients with hyperuricemia, anti-hyperuricemia treatment was associated with lower odds of prevalent CVD.

Circular RNA-protein interactions: functions, mechanisms, and identification.

Circular RNAs (circRNAs) are covalently closed, endogenous RNAs with no 5' end caps or 3' poly(A) tails. These RNAs are expressed in tissue-specific, cell-specific, and developmental stage-specific patterns. The biogenesis of circRNAs is now known to be regulated by multiple specific factors; however, circRNAs were previously thought to be insignificant byproducts of splicing errors. Recent studies have demonstrated their activity as microRNA (miRNA) sponges as well as protein sponges, decoys, scaffolds, and recruiters, and some circRNAs even act as translation templates in multiple pathophysiological processes. CircRNAs bind and sequester specific proteins to appropriate subcellular positions, and they participate in modulating certain protein-protein and protein-RNA interactions. Conversely, several proteins play an indispensable role in the life cycle of circRNAs from biogenesis to degradation. However, the exact mechanisms of these interactions between proteins and circRNAs remain unknown. Here, we review the current knowledge regarding circRNA-protein interactions and the methods used to identify and characterize these interactions. We also summarize new insights into the potential mechanisms underlying these interactions.

IL-6-targeted ultrasmall superparamagnetic iron oxide nanoparticles for optimized MRI detection of atherosclerotic vulnerable plaques in rabbits.

Vulnerable plaques of atherosclerosis (AS) are the main culprit lesion for the serious risk of acute cardiovascular disease (CVD). Therefore, developing new non-invasive methods to detect vulnerable plaques and to evaluate their stability effectively is of great value in the early diagnosis of CVD. IL-6 plays a vital role in the development and rupture of AS. In this study, IL-6-targeted superparamagnetic iron oxide nanoparticles (Anti-IL-6-USPIO) are synthesized by a chemical condensation reaction. An AS model was established by damaging rabbit abdominal aortic intima with Foley's tube in combination with a high cholesterol diet. The results confirm that Anti-IL-6-USPIO have excellent IL-6-targeting ability and usefulness in detecting vulnerable plaques in vitro and in vivo, which may provide a novel, non-invasive strategy for evaluating acute cardiovascular risk or exploiting anti-atherosclerotic drugs.

A Supramolecular Hydrogel of Puerarin.

Supramolecular hydrogels have drawn increased attention because of their advantages in facile synthesis, biocompatibility, easy degradation and fast responses to external stimuli. Until now, the example of hydrogelators of pure natural resources has rarely been reported. Here, we report on a novel hydrogelator of a natural resource, puerarin, which could self-assemble to hydrogels with excellent antioxidant properties and tremendous acid resistance. Our PG-4 could overcome exogenous ROS injury and promote the survival rate of H2O2 treated MSCs by down-regulating SOD activity and MDA level by 21.6% and 28.7% respectively. In addition, utilizing the good acid resistance of PG-4, we investigated its application as an oral formulation. The dissolution rate of puerarin in intestinal-fluid analogue (87.8% at 12 hr) was much faster than that in gastric-fluid analogue (35.6% at 12 hr), which demonstrated that the majority of puerarin was diffused from PG-4 in simulated intestinal fluid. The corresponding pharmacokinetics parameters indicated that PG-4 remarkably improved the absorption of puerarin by oral administration.

Lentiviral vector-mediated co-overexpression of VEGF and Bcl-2 improves mesenchymal stem cell survival and enhances paracrine effects in vitro.

Mesenchymal stem cell (MSC) transplantation has emerged as a promising therapy for ischemic heart disease; however, the low survival rate of transplanted cells limits their therapeutic efficacy. The aim of this study was to investigate whether the dual genetic modification of vascular endothelial growth factor (VEGF) and B­cell lymphoma­2 (Bcl­2) confers a higher expression level of the target genes, better survival and a stronger paracrine effect in MSCs in an adverse environment than the modification of the individual genes. For this purpse, a lentiviral vector was constructed by using a self­cleaving T2A peptide sequence to link and achieve the co­overexpression of VEGF and Bcl­2. Rat MSCs were transfected to obtain cell lines that exhibited a stable overexpression. An in vitro model of oxygen glucose deprivation (OGD) was applied to mimic the ischemic microenvironment, and cell apoptosis, autophagy and the paracrine effects were then determined. Compared with the MSCs in which individual genes were modified and the control MSCs, the MSCs which were subjected to dual genetic modification had a higher expression level of the target genes, a more rapid proliferation, reduced apoptosis, decreased autophagy and an enhanced paracrine effect. Furthermore, the suppression of autophagy was found to contribute to the inhibition of apoptosis in this in vitro OGD model. On the whole, these data indicate that the co­overexpression of VEGF and Bcl­2 protects MSCs in an ischemic environment by inhibiting apoptosis, suppressing autophagy and enhancing the paracrine effects.

Treatment of Myocardial Infarction with Gene-modified Mesenchymal Stem Cells in a Small Molecular Hydrogel.

The effect of transplanted rat mesenchymal stem cells (MSCs) can be reduced by extracellular microenvironment in myocardial infarction (MI). We tested a novel small-molecular hydrogel (SMH) on whether it could provide a scaffold for hepatocyte growth factor (HGF)-modified MSCs and alleviate ventricular remodeling while preserving cardiac function after MI. Overexpression of HGF in MSCs increased Bcl-2 and reduced Bax and caspase-3 levels in response to hypoxia in vitro. Immunocytochemistry demonstrated that cardiac troponin (cTnT), desmin and connexin 43 expression were significantly enhanced in the 5-azacytidine (5-aza) with SMH group compared with the 5-aza only group in vitro and in vivo. Bioluminescent imaging indicated that retention and survival of transplanted cells was highest when MSCs transfected with adenovirus (ad-HGF) were injected with SMH. Heart function and structure improvement were confirmed by echocardiography and histology in the Ad-HGF-SMHs-MSCs group compared to other groups. Our study showed that: HGF alleviated cell apoptosis and promoted MSC growth. SMHs improved stem cell adhesion, survival and myocardial cell differentiation after MSC transplantation. SMHs combined with modified MSCs significantly decreased the scar area and improved cardiac function.

Impact of Timing following Acute Myocardial Infarction on Efficacy and Safety of Bone Marrow Stem Cells Therapy: A Network Meta-Analysis.

Background. The optimal timing for Bone Marrow Stem Cells (BMCs) therapy following acute myocardial infarction (AMI) remains unclear. Aims. To synthesize the evidence from trials using a multiple-treatment comparison method, thereby permitting a broader comparison across multiple timing of BMCs therapy. Methods and Results. Randomized controlled trials in patients with AMI receiving BMCs therapy were identified from PubMed, Ovid LWW, BIOSIS Previews, and the Cochrane Library through January 2015. 2 035 patients of 31 studies included in our analysis were allocated to 5 groups' treatments: 1~3 days, 4~7 days, 8~14 days, 15~30 days, or placebo/control group. The multiple-treatment meta-analysis showed that 4~7 days' group could lead to significantly increased left ventricular ejection fraction (LVEF) as compared with control (mean of MDs and 95% CI: 6 months, 3.05 (0.92~5.25); 12 months, 4.18 (2.30~5.84)). Only 4~7 days led to significant reduction of MACEs compared with control (OR and 95% CI 0.34 (0.13~0.96)) for 12-months follow-up. In simulated comparisons, the 4~7 days' group ranked better than other timing groups for improvement of LVEF or reduction of the incidence of major adverse cardiac events. Conclusions. 4~7 days after AMI might be the optimal timing for cell therapy in terms of efficacy or safety.

Effectiveness and safety of selected bone marrow stem cells on left ventricular function in patients with acute myocardial infarction: a meta-analysis of randomized controlled trials.

BACKGROUND: Concerns regarding the use of selected bone marrow stem cells (BMSCs) in the field of cardiac repair after acute ischemic events have been raised. The current meta-analysis aimed to assess the efficacy and safety of selected BMSC transplantation in patients with acute myocardial infarction (AMI) based on published randomized controlled trials (RCTs). METHODS: A systematic literature search of PubMed, Ovid LWW, BIOSIS Previews, and the Cochrane library from 1990 to 2014 was conducted. Results from RCTs involving subjects with AMI receiving selected BMSC therapy and followed up for at least 6 months were pooled. RESULTS: Eight trials with a total of 262 participants were included. Data were analyzed using a random effects model. Overall, selected BMSC therapy improved left ventricular ejection fraction (LVEF) by 3.17% (95% confidence interval [CI] 0.57-5.76, P=0.02), compared with the controls. There were trends toward reduced left ventricular end-systolic volume (LVESV) and fewer major adverse cardiac events (MACEs). Subgroup analysis revealed a significant difference in LVEF in favor of selected BMSC therapy with bone marrow mesenchymal stem cells (BMMSCs) as the cell type. CONCLUSIONS: Transplantation of selected BMSCs for patients with AMI is safe and induces a significant increase in LVEF with a limited impact on left ventricular remodeling.