Association of Angiotensin II Type 1 Receptor Agonistic Autoantibodies With Outcomes in Patients With Acute Aortic Dissection.

Importance: Angiotensin II is significantly associated with the pathogenesis of acute aortic dissection. Angiotensin II type 1 receptor agonistic autoantibodies (AT1-AAs) can mimic the effect of angiotensin II. Objective: To investigate the association between AT1-AAs and all-cause and cause-specific mortality risk in patients with acute aortic dissection. Design, Setting, and Participants: A total of 662 patients with clinically suspected aortic dissection from 3 medical centers in Wuhan, China, were enrolled in this cohort study from August 1, 2014, to July 31, 2016. Of these, 315 patients were included in the 3-year follow-up study. Follow-up was mainly performed via telephone interviews and outpatient clinic visits. Data analysis was conducted from March 1 to May 31, 2020. Main Outcomes and Measures: The primary outcomes of interest were all-cause mortality, death due to aortic dissection, and late aortic-related adverse events. Results: The full study cohort included 315 patients with AAD (mean [SD] age, 56.2 [12.7] years; 230 men [73.0%]). Ninety-two patients (29.2%) were positive for AT1-AAs. The mortality of AT1-AA-positive patients was significantly higher than that of AT1-AA-negative patients (40 [43.5%] vs 37 [16.6%]; P < .001). The mortality risk in AT1-AA-positive patients was always significantly higher than that in AT1-AA-negative patients in patients with both type A and type B dissection. Multivariable analysis showed that the risk of AT1-AA-positive patients for type A dissection was significantly higher than that of AT1-AA-negative patients (odds ratio [OR], 1.88; 95% CI, 1.12-3.13; P = .02). The Cox proportional hazards regression model showed a significant increase of all-cause mortality risk (OR, 2.27; 95% CI, 1.44-3.57; P < .001) and late aortic-related adverse events (OR, 1.58; 95% CI, 1.06-2.36; P = .03) among AT1-AA-positive patients during the follow-up period compared with AT1-AA-negative patients. Conclusions and Relevance: This cohort study first detected AT1-AAs in patients with acute aortic dissection. The presence of AT1-AAs was associated with significantly higher all-cause and cause-specific mortality during a follow-up period of 3 years. The antibodies may be a risk factor for aortic dissection.

[Platelet-rich plasma injection for the treatment of atrophic fracture nonunion].

OBJECTIVE: To explore clinical effects of platelet rich plasma (PRP) injection in treating atrophic fracture nonunion. METHODS: From March 2015 to March 2017, 15 patients with atrophic fracture nonunion were treated with PRP injection, including 10 males and 5 females, aged from 23 to 56 years old with an average age of (40.0±9.1) years old, the time of fracture nonunion ranged from 6 to 14 months with an average of (8.87±2.45) months. Preparing PRP by extracting 60 to 100 ml peripheral blood. PRP platelet count ranged from 587 to 1 246 with an average of (947.13±158.58) ×10 9 /L. Under the perspective, 13 to 20 ml PRP were injected into the fracture end, and each injection was performed once on the first and the second week of the treatment. Complications such as whether the limb was shortened, angulation, and rotational deformity and radiological examination were observed. RESULTS: All patients were followed up from 6 to 12 months with an average of (6.8± 2.1) months. No shortening, angulation, and rotational deformity occurred. Thirteen patients had fracture healing, the time ranged from 4 to 6 months with an average of (4.8±0.7) months. Two patients had no completely porosis at 12 months during following up, and 1 patient occurred bolt loose. Other patients had no complications. CONCLUSION: The stability of fracture ends of atrophic fracture nonunion after internal fixation is an indication for local PRP injection. PRP treatment for atrophic fractures could completed under local anesthesia, and it has advantages of safe operation and reliable efficacy.

A meta-analysis of the comparing of the first-generation and next-generation TKIs in the treatment of NSCLC.

Background: The current standard approach to the treatment of patients with non-small-cell lung cancer (NSCLC) harboring epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI)-sensitizing mutations has been the treatment with a first-generation EGFR-TKIs. While, with resistance developed against first-generation EGFR-TKIs, second/third-generation TKIs have attracted all the attention, and replaced first-generation EGFR- TKIs upon disease progression due to the greater efficacy and more favorable tolerability. In the past few years, this strategy has been challenged by clinical evidence when next-generation EGFR-TKIs are used in patients with advanced NSCLC. Objective: In this study, we performed a meta- analysis to investigate the efficacy of next-generation TKIs comparison with first-generation TKIs in the treatment of NSCLC. Methods: The multiple databases including Pubmed, Embase, Cochrane library databases were adopted to search for the relevant studies, and full-text articles involving to comparison of next-generation TKIs and first-generation TKIs were reviewed. After rigorous reviewing on quality, the data was extracted from eligible randomized controlled trial (RCT). Meta-analysis Revman 5.3 software was used to analyze the combined pooled ORs with the corresponding 95% confidence interval using fixed- or random-effects models according to the heterogeneity. Results: A total of 5 randomized controlled trials were included in this analysis. The group of next-generation TKIs did achieved benefit in progression-free survival (PFS) (OR = 0.58, 95%CI = 0.45-0.75, P＜0.0001), overall survival (OS) (OR = 0.76, 95%CI = 0.65-0.90, P = 0.001) as well with the objective response rate (ORR) (OR = 1.27, 95%CI = 1.01-1.61, P = 0.04), respectively. In the results of subgroup analysis of PFS with EGFR mutations, there is also significant differences with exon 19 deletion (OR = 0.56, 95%CI = 0.41-0.77, P = 0.0003) and exon 21 (L858R) mutation (OR = 0.60, 95%CI = 0.49-0.75, P＜＝0.00001). While, the treatment-related severe adverse event (SAE) between the next-generation TKIs and first-generation TKIs did not have statistical significance (OR = 1.48, 95%CI = 0.62-3.55, P = 0.38). Conclusion: The next-generation TKIs significantly improved efficacy outcomes in the treatment of EGFR mutation-positive advanced NSCLC compared with the first-generation TKIs, with a manageable safety profile. These results are potentially important for clinical decision making for these patients.

KPC1 alleviates hypoxia/reoxygenation-induced apoptosis in rat cardiomyocyte cells though BAX degradation.

Bax triggers cell apoptosis by permeabilizing the outer mitochondrial membrane, leading to membrane potential loss and cytochrome c release. However, it is unclear if proteasomal degradation of Bax is involved in the apoptotic process, especially in heart ischemia-reperfusion (I/R)-induced injury. In the present study, KPC1 expression was heightened in left ventricular cardiomyocytes of patients with coronary heart disease (CHD), in I/R-myocardium in vivo and in hypoxia and reoxygenation (H/R)-induced cardiomyocytes in vitro. Overexpression of KPC1 reduced infarction size and cell apoptosis in I/R rat hearts. Similarly, the forced expression of KPC1 restored mitochondrial membrane potential (MMP) and cytochrome c release driven by H/R in H9c2 cells, whereas reducing cell apoptosis, and knockdown of KPC1 by short-hairpin RNA (shRNA) deteriorated cell apoptosis induced by H/R. Mechanistically, forced expression of KPC1 promoted Bax protein degradation, which was abolished by proteasome inhibitor MG132, suggesting that KPC1 promoted proteasomal degradation of Bax. Furthermore, KPC1 prevented basal and apoptotic stress-induced Bax translocation to mitochondria. Bax can be a novel target for the antiapoptotic effects of KPC1 on I/R-induced cardiomyocyte apoptosis and render mechanistic penetration into at least a subset of the mitochondrial effects of KPC1.

VEGF-A and VEGF-B Coordinate the Arteriogenesis to Repair the Infarcted Heart with Vagus Nerve Stimulation.

BACKGROUND/AIMS: Vagus nerve stimulation (VNS) suppresses arrhythmic activity and minimizes cardiomyocyte injury. However, how VNS affects angiogenesis/arteriogenesis in infarcted hearts, is poorly understood. METHODS: Myocardial infarction (MI) was achieved by ligation of the left anterior descending coronary artery (LAD) in rats. 7 days after LAD, stainless-steel wires were looped around the left and right vagal nerve in the neck for vagus nerve stimulation (VNS). The vagal nerve was stimulated with regular pulses of 0.2ms duration at 20 Hz for 10 seconds every minute for 4 hours, and then ACh levels by ELISA in cardiac tissue and serum were evaluated for its release after VNS. Three and 14 days after VNS, Real-time PCR, immunostaining and western blot were respectively used to determine VEGF-A/B expressions and α-SMA- and CD31-postive vessels in VNS-hearts with pretreatment of α7-nAChR blocker mecamylamine (10 mg/kg, ip) or mACh-R blocker atropine (10 mg/kg, ip) for 1 hour. The coronary function and left ventricular performance were analyzed by Langendorff system and hemodynamic parameters in VNS-hearts with pretreatment of VEGF-A/B-knockdown or VEGFR blocker AMG706. Coronary arterial endothelial cells proliferation, migration and tube formation were evaluated for angiogenesis following the stimulation of VNS in coronary arterial smooth muscle cells (VSMCs). RESULTS: VNS has been shown to stimulate VEGF-A and VEGF-B expressions in coronary arterial smooth muscle cells (VSMCs) and endothelial cells (ECs) with an increase of α-SMA- and CD31-postive vessel number in infarcted hearts. The VNS-induced VEGF-A/B expressions and angiogenesis were abolished by m-AChR inhibitor atropine and α7-nAChR blocker mecamylamine in vivo. Interestingly, knockdown of VEGF-A by shRNA mainly reduced VNS-mediated formation of CD31+ microvessels. In contrast, knockdown of VEGF-B powerfully abrogated VNS-induced formation of α-SMA+ vessels. Consistently, VNS-induced VEGF-A showed a greater effect on EC tube formation as compared to VNS-induced VEGF-B. Moreover, VEGF-A promoted EC proliferation and VSMC migration while VEGF-B induced VSMC proliferation and EC migration in vitro. Mechanistically, vagal neurotransmitter acetylcholine stimulated VEGF-A/B expressions through m/nACh-R/PI3K/Akt/Sp1 pathway in EC. Functionally, VNS improved the coronary function and left ventricular performance. However, blockade of VEGF receptor by antagonist AMG706 or knockdown of VEGF-A or VEGF-B by shRNA significantly diminished the beneficial effects of VNS on ventricular performance. CONCLUSION: VNS promoted angiogenesis/arteriogenesis to repair the infracted heart through the synergistic effects of VEGF-A and VEGF-B.

Data on the involvement of Meox1 in balloon-injury-induced neointima formation of rats.

In the previous report, Meox1 was found to promote SMCs phenotypic modulation and injury-induced vascular remodeling by regulating the FAK-ERK1/2-autophagy signaling cascade (Wu et al., 2017) [1]. Here, we presented new original data on the involvement of Mesoderm/mesenchyme homeobox gene l (Meox1) in balloon-injury-induced neointima formation of rat. In rat carotid artery balloon injury model to induce vascular remodeling, Meox1 was induced in vascular smooth muscle cell (SMCs) of rat carotid arteries. Most proliferating cell nuclear antigen (PCNA)-positive cells also expressed Meox1. These data suggested that Meox1 may be involved in SMCs proliferation during injury-induced neointima formation. Furthermore, knocked down its expression in injured arteries by adenoviral delivery of Meox1 short hairpin RNA (shRNA) (shMeox1), neointima formation was significantly inhibited. Elastin staining also confirmed the reduction of neointima in Meox1 shRNA-transduced arteries. Moreover, knockdown of Meox1 decreased the collagen production/deposition that was significantly increased in neointima induced by balloon injury.

Mesoderm/mesenchyme homeobox gene l promotes vascular smooth muscle cell phenotypic modulation and vascular remodeling.

AIMS: To investigate the role of mesoderm/mesenchyme homeobox gene l (Meox1) in vascular smooth muscle cells (SMCs) phenotypic modulation during vascular remodeling. METHODS AND RESULTS: By using immunostaining, Western blot, and histological analyses, we found that Meox1 was up-regulated in PDGF-BB-treated SMCs in vitro and balloon injury-induced arterial SMCs in vivo. Meox1 knockdown by shRNA restored the expression of contractile SMCs phenotype markers including smooth muscle α-actin (α-SMA) and calponin. In contrast, overexpression of Moex1 inhibited α-SMA and calponin expressions while inducing the expressions of synthetic SMCs phenotype markers such as matrix gla protein, osteopontin, and proliferating cell nuclear antigen. Mechanistically, Meox1 mediated the SMCs phenotypic modulation through FAK-ERK1/2 signaling, which appears to induce autophagy in SMCs. In vivo, knockdown of Meox1 attenuated injury-induced neointima formation and promoted SMCs contractile proteins expressions. Meox1 knockdown also reduced the number of proliferating SMCs, suggesting that Meox1 was important for SMCs proliferation in vivo. Moreover, knockdown of Meox1 attenuated ERK1/2 signaling and autophagy markers expressions, suggesting that Meox1 may promote SMCs phenotypic modulation via ERK1/2 signaling-autophagy in vivo. CONCLUSION: Our data indicated that Meox1 promotes SMCs phenotypic modulation and injury-induced vascular remodeling by regulating the FAK-ERK1/2-autophagy signaling cascade. Thus, targeting Meox1 may be an attractive approach for treating proliferating vascular diseases.

S100B promotes injury-induced vascular remodeling through modulating smooth muscle phenotype.

S100B is a biomarker of nervous system injury, but it is unknown if it is also involved in vascular injury. In the present study, we investigated S100B function in vascular remodeling following injury. Balloon injury in rat carotid artery progressively induced neointima formation while increasing S100B expression in both neointimal vascular smooth muscle (VSMC) and serum along with an induction of proliferating cell nuclear antigen (PCNA). Knockdown of S100B by its shRNA delivered by adenoviral transduction attenuated the PCNA expression and neointimal hyperplasia in vivo and suppressed PDGF-BB-induced VSMC proliferation and migration in vitro. Conversely, overexpression of S100B promoted VSMC proliferation and migration. Mechanistically, S100B altered VSMC phenotype by decreasing the contractile protein expression, which appeared to be mediated by NF-κB activity. S100B induced NF-κB-p65 gene transcription, protein expression and nuclear translocation. Blockade of NF-κB activity by its inhibitor reversed S100B-mediated downregulation of VSMC contractile protein and increase in VSMC proliferation and migration. It appeared that S100B regulated NF-κB expression through, at least partially, the Receptor for Advanced Glycation End products (RAGE) because RAGE inhibitor attenuated S100B-mediated NF-κB promoter activity as well as VSMC proliferation. Most importantly, S100B secreted from VSMC impaired endothelial tube formation in vitro, and knockdown of S100B promoted re-endothelialization of injury-denuded arteries in vivo. These data indicated that S100B is a novel regulator for vascular remodeling following injury and may serve as a potential biomarker for vascular damage or drug target for treating proliferative vascular diseases.

Phthalate levels and related factors in children aged 6-12 years.

Although previous studies showed that children are widely exposed to phthalates, the sources of phthalate exposure for school-aged children in China are not well understood. This study aimed to assess phthalate metabolite levels and explore the factors influencing exposure in children. We collected demographic data and biological samples from 336 children aged 6-12 years. We calculated urinary concentrations of 14 mono-phthalate metabolites and conducted chi-square (χ2) tests and logistic regression analysis to determine the variables associated with phthalate levels. Mono-n-butyl phthalate (MnBP) and mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) were the most abundant urinary phthalate metabolites. In addition, housing type, decorating materials in the home, and frequency of canned food consumption were associated with exposure to low molecular weight phthalates. Water source, duration of time spent playing with toys, residential area, and frequency of canned food consumption were associated with exposure to high molecular weight phthalates. Based on these results, potential strategies to reduce exposure to phthalates include avoiding plastic food containers and chemical fragrances as well as eating fewer processed foods, especially canned foods, and foods in plastic packaging.

Exposure to phthalates in children aged 5-7years: Associations with thyroid function and insulin-like growth factors.

This study aimed to evaluate the associations between phthalate concentrations and thyroid function in preschool children. We collected demographic data and biological samples from 216 children aged 5-7years. We calculated urinary concentrations of eight mono-phthalate metabolites (mPAEs) separately for children from urban and rural areas and investigated their associations with thyroid function and growth hormones. mPAE concentrations were higher in children from the urban area than in those from the rural area, and most mPAEs were positively associated with free triiodothyronine and free thyroxine. The insulin-like growth factor 1 (IGF-1) concentration decreased 0.082ng/mL (95% confidence interval [CI]: -1.34, -0.113) with each 1ng/mL increase in monomethyl phthalate (MMP) and 0.132ng/mL (95% CI: -0.209, -0.055) with each 1ng/mL increase in mono-n-butyl phthalate. The insulin-like growth factor binding protein 3 concentration decreased by 0.01mg/L (95% CI: -0.001, -0.000) or 0.01mg/L (95% CI: -0.003, -0.000) with each 1ng/mL increase in MMP or monoethyl phthalate, respectively. Exposure to some phthalates at 5-7years of age might interfere with thyroid hormones and growth.

Vascular endothelial growth factor-C protects heart from ischemia/reperfusion injury by inhibiting cardiomyocyte apoptosis.

VEGF-C is a newly identified proangiogenic protein playing an important role in vascular disease and angiogenesis. However, its role in myocardial ischemia/reperfusion (I/R) injury remains unknown. The objective of this study was to determine the role and mechanism of VEGF-C in myocardial ischemia-reperfusion injury. Rat left ventricle myocardium was injected with recombinant human VEGF-C protein (0.1 or 1.0 µg/kg b.w.) 1 h prior to myocardial ischemia-reperfusion (I/R) injury. 24 h later, the myocardial infarction size, the number of TUNEL-positive cardiomyocytes, the levels of creatine kinase (CK), CK-MB, cardiac troponin, malondialdehyde (MDA) content, and apoptosis protein Bax expression were decreased, while Bcl2 and pAkt expression were increased in VEGF-C-treated myocardium as compared to the saline-treated I/R hearts. VEGF-C also improved the function of I/R-injured hearts. In the H2O2-induced H9c2 cardiomyocytes, which mimicked the I/R injury in vivo, VEGF-C pre-treatment decreased the LDH release and MDA content, blocked H2O2-induced apoptosis by inhibiting the pro-apoptotic protein Bax expression and its translocation to the mitochondrial membrane, and consequently attenuated H2O2-induced decrease of mitochondrial membrane potential and increase of cytochrome c release from mitochondria. Mechanistically, VEGF-C activated Akt signaling pathway via VEGF receptor 2, leading to a blockade of Bax expression and mitochondrial membrane translocation and thus protected cardiomyocyte from H2O2-induced activation of intrinsic apoptotic pathway. VEGF-C exerts its cardiac protection following I/R injury via its anti-apoptotic effect.

PEP-1-SOD1 fusion proteins block cardiac myofibroblast activation and angiotensin II-induced collagen production.

BACKGROUND: Oxidative stress is closely associated with cardiac fibrosis. However, the effect of copper, zinc-superoxide dismutase (SOD1) as a therapeutic agent is limited due to the insufficient transduction. This study was aimed to investigate the effect of PEP-1-SOD1 fusion protein on angiotensin II (ANG II)-induced collagen metabolism in rat cardiac myofibroblasts (MCFs). METHODS: MCFs were pretreated with SOD1 or PEP-1-SOD1 fusion protein for 2 h followed by incubation with ANG II for 24 h. Cell proliferation was measured by Cell Counting Kit-8. Superoxide anion productions were detected by both fluorescent microscopy and Flow Cytometry. MMP-1 and TIMP-1 were determined by ELISA. Intracellular MDA content and SOD activity were examined by commercial assay kits. Protein expression was analyzed by western blotting. RESULTS: PEP-1-SOD1 fusion protein efficiently transduced into MCF, scavenged intracellular O2 (-), decreased intracellular MDA content, increased SOD activity, suppressed ANG II-induced proliferation, reduced expression of TGF-ß1, α-SMA, collagen type I and III, restored MMP-1 secretion, and attenuated TIMP-1 secretion. CONCLUSION: PEP-1-SOD1 suppressed MCF proliferation and differentiation and reduced production of collagen type I and III. Therefore, PEP-1-SOD1 fusion protein may be a potential novel therapeutic agent for cardiac fibrosis.

VEGF-A promotes cardiac stem cell engraftment and myocardial repair in the infarcted heart.

BACKGROUND: The objective of this study was to determine whether vascular endothelial growth factor (VEGF)-A subtypes improve cardiac stem cell (CSC) engraftment and promote CSC-mediated myocardial repair in the infarcted heart. METHODS: CSCs were treated with VEGF receptor (VEGFR) inhibitors, VCAM-1 antibody (VCAM-1-Ab), or PKC-α inhibitor followed by the treatment with VEGF-A. CSC adhesion assays were performed in vitro. In vivo, the PKH26-labeled and VCAM-1-Ab or PKC-α inhibitor pre-treated CSCs were treated with VEGF-A followed by implantation into infarcted rat hearts. The hearts were then collected for measuring CSC engraftment and evaluating cardiac fibrosis and function 3 or 28days after the CSC transplantation. RESULTS: All three VEGF-A subtypes promoted CSC adhesion to extracellular matrix and endothelial cells. VEGF-A-mediated CSC adhesion required VEGFR and PKCα signaling. Importantly, VEGF-A induced VCAM-1, but not ICAM-1 expression in CSCs through PKCα signaling. In vivo, VEGF-A promoted the engraftment of CSCs in infarcted hearts, which was attenuated by PKCα inhibitor or VCAM-1-Ab. Moreover, VEGF-A-mediated CSC engraftment resulted in a reduction in infarct size and fibrosis. Functional studies showed that the transplantation of the VEGF-A-treated CSCs stimulated extensive angiomyogenesis in infarcted hearts as indicated by the expression of cardiac troponin T and von Willebrand factor, leading to an improved performance of left ventricle. Blockade of PKCα signaling or VCAM-1 significantly diminished the beneficial effects of CSCs treated with VEGF-A. CONCLUSION: VEGF-A promotes myocardial repair through, at least in part, enhancing the engraftment of CSCs mediated by PKCα/VCAM-1 pathway.

PEP-1-CAT protects hypoxia/reoxygenation-induced cardiomyocyte apoptosis through multiple sigaling pathways.

BACKGROUND: Catalase (CAT) breaks down H2O2 into H2O and O2 to protects cells from oxidative damage. However, its translational potential is limited because exogenous CAT cannot enter living cells automatically. This study is aimed to investigate if PEP-1-CAT fusion protein can effectively protect cardiomyocytes from oxidative stress due to hypoxia/reoxygenation (H/R)-induced injury. METHODS: H9c2 cardomyocytes were pretreated with catalase (CAT) or PEP-1-CAT fusion protein followed by culturing in a hypoxia and re-oxygenation condition. Cell apoptosis were measured by Annexin V and PI double staining and Flow cytometry. Intracellular superoxide anion level was determined, and mitochondrial membrane potential was measured. Expression of apoptosis-related proteins including Bcl-2, Bax, Caspase-3, PARP, p38 and phospho-p38 was analyzed by western blotting. RESULTS: PEP-1-CAT protected H9c2 from H/R-induced morphological alteration and reduced the release of lactate dehydrogenase (LDH) and malondialdehyde content. Superoxide anion production was also decreased. In addition, PEP-1-CAT inhibited H9c2 apoptosis and blocked the expression of apoptosis stimulator Bax while increased the expression of Bcl-2, leading to an increased mitochondrial membrane potential. Mechanistically, PEP-1-CAT inhibited p38 MAPK while activating PI3K/Akt and Erk1/2 signaling pathways, resulting in blockade of Bcl2/Bax/mitochondrial apoptotic pathway. CONCLUSION: Our study has revealed a novel mechanism by which PEP-1-CAT protects cardiomyocyte from H/R-induced injury. PEP-1-CAT blocks Bcl2/Bax/mitochondrial apoptotic pathway by inhibiting p38 MAPK while activating PI3K/Akt and Erk1/2 signaling pathways.

Apigenin sensitizes doxorubicin-resistant hepatocellular carcinoma BEL-7402/ADM cells to doxorubicin via inhibiting PI3K/Akt/Nrf2 pathway.

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a redox- sensitive transcription factor regulating expression of a number of cytoprotective genes. Recently, Nrf2 has emerged as an important contributor to chemoresistance in cancer therapy. In the present study, we found that non-toxic dose of apigenin (APG) significantly sensitizes doxorubicin-resistant BEL-7402 (BEL-7402/ADM) cells to doxorubicin (ADM) and increases intracellular concentration of ADM. Mechanistically, APG dramatically reduced Nrf2 expression at both the messenger RNA and protein levels through downregulation of PI3K/Akt pathway, leading to a reduction of Nrf2-downstream genes. In BEL-7402 xenografts, APG and ADM cotreatment inhibited tumor growth, reduced cell proliferation and induced apoptosis more substantially when compared with ADM treatment alone. These results clearly demonstrate that APG can be used as an effective adjuvant sensitizer to prevent chemoresistance by downregulating Nrf2 signaling pathway.

Acetylcholine induces mesenchymal stem cell migration via Ca2+ /PKC/ERK1/2 signal pathway.

Acetylcholine (ACh) plays an important role in neural and non-neural function, but its role in mesenchymal stem cell (MSC) migration remains to be determined. In the present study, we have found that ACh induces MSC migration via muscarinic acetylcholine receptors (mAChRs). Among several mAChRs, MSCs express mAChR subtype 1 (m1AChR). ACh induces MSC migration via interaction with mAChR1. MEK1/2 inhibitor PD98059 blocks ERK1/2 phosphorylation while partially inhibiting the ACh-induced MSC migration. InsP3Rs inhibitor 2-APB that inhibits MAPK/ERK phosphorylation completely blocks ACh-mediated MSC migration. Interestingly, intracellular Ca(2+) ATPase-specific inhibitor thapsigargin also completely blocks ACh-induced MSC migration through the depletion of intracellular Ca(2+) storage. PKCα or PKCß inhibitor or their siRNAs only partially inhibit ACh-induced MSC migration, but PKC-ζ siRNA completely inhibits ACh-induced MSC migration via blocking ERK1/2 phosphorylation. These results indicate that ACh induces MSC migration via Ca(2+), PKC, and ERK1/2 signal pathways.

[Effect of conditioned medium of mesenchymal stem cells on proliferation, migration and adhesion of human umbilical vein endothelial cells].

The aim of this study was to explore the effect of mesenchymal stem cell (MSC) conditioned medium (MSC-CM) on proliferation, migration and adhesion of human umbilical vein endothelial cell (CRL1730) and its mechanism. Isolation and purification of MSC were performed with the classic adhering method, the surface markers (CD29, CD90, CD45 and CD34) in MSC were detected by flow cytometry. MSC were treated and cultured for 3 d, the MSC-CM or MSC overexpressing stem cell-derived factor-1 (SDF-1) conditioned medium (Ad-SDF-1-MSC-CM) were collected. Subsequently, CRL1730 cells were treated respectively with 2% FBS-DMEM, 15% FBS-DMEM (control group), MSC-CM or Ad-SDF-1-MSC-CM for 24 h, the proliferation of CRL1730 cells was detected by MTT method. CRL1730 cell migration in vitro was performed by using wound healing system. The adhesion ability of CRL1730 cells was analyzed by microscope. The results indicated that the CRL1730 cells treated with Ad-SDF-1-MSC-CM showed greater proliferative capacity than CRL1730 cells treated with MSC-CM. While adding with AMD3100 5 µmol/L, the blocker of CXCR4, the CRL1730 proliferation mediated by Ad-SDF-1-MSC-CM was significantly reduced. Meanwhile, compared with MSC-CM, Ad-SDF-1-MSC-CM had greater effects for promoting CRL1730 migration and enhancing adhesion ability of CRL1730 cells, these effects were significantly inhibited by AMD3100. It is concluded that MSC-CM promotes the migration and adhesion ability of CRL1730 cells through SDF-1 expressed by MSC.

VEGF is essential for the growth and migration of human hepatocellular carcinoma cells.

Vascular endothelial growth factor (VEGF) plays a crucial role in tumor angiogenesis. VEGF induces new vessel formation and tumor growth by inducing mitogenesis and chemotaxis of normal endothelial cells and increasing vascular permeability. However, little is known about VEGF function in the proliferation, survival or migration of hepatocellular carcinoma cells (HCC). In the present study, we have found that VEGF receptors are expressed in HCC line BEL7402 and human HCC specimens. Importantly, VEGF receptor expression correlates with the development of the carcinoma. By using a comprehensive approaches including TUNEL assay, transwell and wound healing assays, migration and invasion assays, adhesion assay, western blot and quantitative RT-PCR, we have shown that knockdown of VEGF165 expression by shRNA inhibits the proliferation, migration, survival and adhesion ability of BEL7402. Knockdown of VEGF165 decreased the expression of NF-κB p65 and PKCα while increased the expression of p53 signaling molecules, suggesting that VEGF functions in HCC proliferation and migration are mediated by P65, PKCα and/or p53.

PEP-1-CAT-transduced mesenchymal stem cells acquire an enhanced viability and promote ischemia-induced angiogenesis.

OBJECTIVE: Poor survival of mesenchymal stem cells (MSC) compromised the efficacy of stem cell therapy for ischemic diseases. The aim of this study is to investigate the role of PEP-1-CAT transduction in MSC survival and its effect on ischemia-induced angiogenesis. METHODS: MSC apoptosis was evaluated by DAPI staining and quantified by Annexin V and PI double staining and Flow Cytometry. Malondialdehyde (MDA) content, lactate dehydrogenase (LDH) release, and Superoxide Dismutase (SOD) activities were simultaneously measured. MSC mitochondrial membrane potential was analyzed with JC-1 staining. MSC survival in rat muscles with gender-mismatched transplantation of the MSC after lower limb ischemia was assessed by detecting SRY expression. MSC apoptosis in ischemic area was determined by TUNEL assay. The effect of PEP-1-CAT-transduced MSC on angiogenesis in vivo was determined in the lower limb ischemia model. RESULTS: PEP-1-CAT transduction decreased MSC apoptosis rate while down-regulating MDA content and blocking LDH release as compared to the treatment with H(2)O(2) or CAT. However, SOD activity was up-regulated in PEP-1-CAT-transduced cells. Consistent with its effect on MSC apoptosis, PEP-1-CAT restored H(2)O(2)-attenuated mitochondrial membrane potential. Mechanistically, PEP-1-CAT blocked H(2)O(2)-induced down-regulation of PI3K/Akt activity, an essential signaling pathway regulating MSC apoptosis. In vivo, the viability of MSC implanted into ischemic area in lower limb ischemia rat model was increased by four-fold when transduced with PEP-1-CAT. Importantly, PEP-1-CAT-transduced MSC significantly enhanced ischemia-induced angiogenesis by up-regulating VEGF expression. CONCLUSIONS: PEP-1-CAT-transduction was able to increase MSC viability by regulating PI3K/Akt activity, which stimulated ischemia-induced angiogenesis.

[Effect of vascular endothelial growth factor on bone marrow-derived mesenchymal stem cell proliferation and the signaling mechanism].

OBJECTIVE: To observe the effect of vascular endothelial growth factor (VEGF) on bone marrow-derived mesenchymal stem cell (MSC) proliferation and explore the signaling mechanism involved. METHODS: MSC culture was performed following the classical whole bone marrow adhering method. The characteristics of MSC were identified by induction of multi-lineage differentiation and flow cytometry for surface marker analysis (CD34, CD45, CD29, and CD90). Following the addition of 50 nmol/L wortmannin, 50 µmol/L PD98059, 30 µmol/L SB203580, 10 µmol/L H89, 20 µmol/L Y27632, 1 µmol/L rapamycin, 10 µmol/L straurosporine, 6 nmol/L Go6976, or 50 µmol/L Pseudo Z inhibitors in the cell culture, the MSC were treated with 20 ng/ml VEGF and the changes of the cell proliferation rate was measured with MTT assay. RESULTS: Cultured MSC were capable of multi-linage differentiation and did not express VEGF-R, CD29 or CD90. Treatment with 20 ng/ml VEGF obviously promoted MSC proliferation, and this effect was inhibited partially by p38 mitogen-activated protein kinase (MAPK) inhibitor rapamycin, PD98059, SB203580, Go6976, and straurosporine. CONCLUSIONS: VEGF promotes MSC proliferation in close relation to the AKT-PKC pathway, in which PKC signal pathway may play the central role.