Association between diabetes mellitus and primary restenosis following endovascular treatment: a comprehensive meta-analysis of randomized controlled trials.

IMPORTANCE: Diabetes mellitus (DM) is thought to be closely related to arterial stenotic or occlusive disease caused by atherosclerosis. However, there is still no definitive clinical evidence to confirm that patients with diabetes have a higher risk of restenosis. OBJECTIVE: This meta-analysis was conducted to determine the effect of DM on restenosis among patients undergoing endovascular treatment, such as percutaneous transluminal angioplasty (PTA) or stenting. DATA SOURCES AND STUDY SELECTION: The PubMed/Medline, EMBASE and Cochrane Library electronic databases were searched from 01/1990 to 12/2022, without language restrictions. Trials were included if they satisfied the following eligibility criteria: (1) RCTs of patients with or without DM; (2) lesions confined to the coronary arteries or femoral popliteal artery; (3) endovascular treatment via PTA or stenting; and (4) an outcome of restenosis at the target lesion site. The exclusion criteria included the following: (1) greater than 20% of patients lost to follow-up and (2) a secondary restenosis operation. DATA EXTRACTION AND SYNTHESIS: Two researchers independently screened the titles and abstracts for relevance, obtained full texts of potentially eligible studies, and assessed suitability based on inclusion and exclusion criteria.. Disagreements were resolved through consultation with a third researcher. Treatment effects were measured by relative ratios (RRs) with 95% confidence intervals (CIs) using random effects models. The quality of the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria. MAIN OUTCOMES AND MEASURES: The main observation endpoint was restenosis, including > 50% stenosis at angiography, or TLR of the primary operation lesion during the follow-up period. RESULTS: A total of 31,066 patients from 20 RCTs were included. Patients with DM had a higher risk of primary restenosis after endovascular treatment (RR = 1.43, 95% CI: 1.25-1.62; p = 0.001). CONCLUSIONS AND RELEVANCE: This meta-analysis of all currently available RCTs showed that patients with DM are more prone to primary restenosis after endovascular treatment.

Built-In Positive Valence Space Shifting the Chemical Equilibrium Forward for Nitrate Reduction to Ammonia.

The electrochemical conversion of nitrate pollutants into value-added ammonia (NH3) is an appealing alternative synthetic route for sustainable NH3 production. However, the development of the electrocatalytic nitrate-to-ammonia reduction reaction (NO3RR) has been hampered by unruly reactants and products at the interface and the accompanied sluggish kinetic rate. In this work, a built-in positive valence space is successfully constructed over FeCu nanocrystals to rationally regulate interfacial component concentrations and positively shift the chemical equilibrium. With positive valence Cu optimizing the active surface, the space between the stern and shear layers becomes positive, which is able to continuously attract the negatively charged NO3- reactant and repulse the positively charged NH4+ product even under high current density, thus significantly boosting the NO3RR kinetics. The system with a built-in positive valence space affords an ampere-level NO3RR performance with the highest NH3 yield rate of 150.27 mg h-1 mg-1 at -1.3 V versus RHE with an outstanding NH3 current density of 189.53 mA cm-2, as well as a superior Faradaic efficiency (FE) of 97.26% at -1.2 V versus RHE. The strategy proposed here underscores the importance of interfacial concentration regulation and can find wider applicability in other electrochemical syntheses suffering from sluggish kinetics.

Eliminating Concentration Polarization with Cationic Covalent Organic Polymer to Promote Effective Overpotential of Nitrogen Fixation.

Electrocatalytic nitrogen reduction reaction offers a sustainable alternative to the conventional Haber-Bosch process. However, it is currently restricted by low effective overpotential due to the concentration polarization, which arises from accumulated products, ammonium, at the reaction interface. Here, a novel covalent organic polymer with ordered periodic cationic sites is proposed to tackle this challenge. The whole network exhibits strong positive charge and effectively repels the positively charged ammonium, enabling an ultra-low interfacial product concentration, and successfully driving the reaction equilibrium to the forward direction. With the given potential unchanged, the suppressed overpotential can be much liberated, ultimately leading to a continuous high-level reaction rate. As expected, when this tailored microenvironment is coupled with a transition metal-based catalyst, a 24-fold improvement is generated in the Faradaic efficiency (73.74 %) as compared with the bare one. The proposed strategy underscores the importance of optimizing dynamic processes as a means of improving overall performance in electrochemical syntheses.

MiR-146a protects small intestine against ischemia/reperfusion injury by down-regulating TLR4/TRAF6/NF-κB pathway.

Previous studies reported that miR-146a was involved in small intestine ischemia-reperfusion (I/R) injury, but the mechanism is largely vague. Here, we aimed to identify the change of miR-146a in patients with mesenteric ischemia and explore the potential regulatory mechanism of miR-146a in intestine epithelial cells survival under ischemia and I/R injury. The plasma of 20 patients with mesenteric ischemia and 25 controls was collected to examine the miR-146a expression by qPCR. Rat intestinal epithelial cells (IEC-6) and 24 male Sprague-Dawley rats were included to build ischemia and I/R model in vitro and in vivo. The qPCR results showed that miR-146a decreased both in the plasma of patients with mesenteric ischemia and in IEC-6 cells and rat small intestine tissues in ischemia and I/R model compared to controls. Both the in vitro and in vivo results showed that I/R resulted in more severe apoptotic injury than ischemia. Cleaved-caspase 3, TLR4, TRAF6, and nuclear NF-κB p65 were up-regulated accompanying reduced XIAP and SOCS3 expression in intestinal ischemia and I/R injury. After up-regulation of miR-146a in IEC-6 cells, increased cell survival and decreased cell apoptosis were observed, concomitant with decreased cleaved-caspase 3 and down-regulated TLR4/TRAF6/NF-κB pathway. What is more, this protective effect was blocked by TRAF6 overexpression and increased nuclear NF-κB p65 nuclear. Taken together, this study revealed that miR-146a expression was decreased in small intestine ischemia and I/R injury. And miR-146a improves intestine epithelial cells survival under ischemia and I/R injury through inhibition TLR4, TRAF6, and p-IκBα, subsequently leading to decreased NF-κB p65 nuclear translocation.

Downregulation of MicroRNA-4463 Attenuates High-Glucose- and Hypoxia-Induced Endothelial Cell Injury by Targeting PNUTS.

BACKGROUND/AIMS: Vascular complications are the main reasons for disability and mortality associated with type 2 diabetes mellitus (T2DM) and numerous microRNAs (miRNAs) are involved in this process. Our previous study demonstrated that miR-4463 was increased in the plasma of T2DM patients combined with arteriosclerosis of low extremity artery (ASO). However, the role of miR-4463 remains unclear. METHODS: miR-4463 expression in the vascular tissues of patients with ASO and T2DM and in human umbilical vein endothelial cells (HUVECs) was detected by qPCR. Cell survival and apoptosis was analyzed via Cell Counting Kit-8 and flow cytometry assays, respectively. Protein expression was determined by Western blot and protein subcellular localization was detected with immunofluorescence. A dual-luciferase assay was used to elucidate the target gene of miR-4463. RESULTS: miR-4463 was elevated in the vascular tissues of patients with T2DM and ASO. In HUVECs, both 25 mmol/L glucose (high glucose, HG) and hypoxia induced miR-4463 expression. Downregulation of miR-4463 promoted HUVEC survival and reduced cell apoptosis under HG and/or hypoxic conditions by facilitating the expression of protein phosphatase-1 nuclear targeting subunit (PNUTS), X-linked inhibitor of apoptosis protein (XIAP), p-AKT, p-Bad, increased the Bcl-2/Bax ratio, as well as downregulated cleaved caspase 3 expression. Mechanistically, we identified PNUTS as a direct target gene of miR-4463. Both the inhibition of AKT phosphorylation and silencing of PNUTS diminished the effect of miR-4463 on HUVEC apoptosis. Moreover, downregulation of miR-4463 enhanced PNUTS to enable PTEN nuclear localization, which resulted in AKT phosphorylation. CONCLUSION: Our results suggest that downregulation of miR-4463 attenuates cell apoptosis by directly enhancing PNUTS expression to promote PTEN nuclear localization, subsequently activating AKT signaling pathway in HUVECs under HG and/ or hypoxic conditions.

A Single-Center Retrospective Analysis of the Efficacy of a New Balloon Catheter in Autogenous Arteriovenous Fistula Dysfunction Resistant to Conventional Balloon Angioplasty.

PURPOSE: The purpose of the study was to present a new alternative balloon catheter option for autogenous arteriovenous fistula (AVF) dysfunction with a stiff constriction resistant to conventional balloon angioplasty. METHODS: Our first series of 51 patients with autogenous AVF dysfunction who were simultaneously treated with VascuTrak™ balloon catheter, following failed conventional balloon therapy (failure was defined as residual stenosis of >30%), were retrospectively observed and analyzed. The indices that were used to evaluate the clinical efficacy of VascuTrak balloon catheter included the immediate technical success rate, residual stenosis, successful dilation times, degree of pain assessed using the Visual Analog Scale, complications, and follow-up patency rate. RESULTS: The stenotic or occlusive lesions of all 51 cases resistant to conventional balloon angioplasty were promptly eliminated or alleviated (residual stenosis rate ≤ 30%), with a 100% immediate technical success rate. VascuTrak balloon catheters were successful in achieving full dilation under working pressure, of which 44 cases required a 1-time dilation (86.3%) and 7 cases required 2 dilations, which differed significantly from the average of 2.4 dilations required by the preceding conventional balloon therapy (P < 0.0001). A statistically significant improvement in the degree of pain experienced by patients who received VascuTrak balloon dilation was observed compared to that of the preceding conventional balloon dilation (P < 0.0001). One case of a brachial artery pseudoaneurysm complication occurred in the perioperative period. The primary patency rate was 88.2% at 6 months and 74.5% at 12 months. CONCLUSION: The use of VascuTrak balloon catheter to treat autogenous AVF dysfunction resistant to conventional balloon angioplasty appears to be safe and effective, although further, large randomized controlled trials are necessary.

Endothelial Cells Inhibit the Angiotensin II Induced Phenotypic Modulation of Rat Vascular Adventitial Fibroblasts.

The phenotypic modulation of vascular adventitial fibroblasts plays an important role in vascular remodeling. Evidence have shown that endothelial cells and adventitial fibroblasts interact under certain conditions. In this study, we investigated the influence of endothelial cells on the phenotypic modulation of adventitial fibroblasts. Endothelial cells and adventitial fibroblasts from rat thoracic aorta were cultivated in a co-culture system and adventitial fibroblasts were induced with angiotensin II (Ang II). Collagen I and alpha smooth muscle actin (α-SMA) expression and migration of adventitial fibroblasts were analyzed. Ang II upregulated the expression of collagen I and α-SMA and the migration of adventitial fibroblasts. Adventitial fibroblasts-endothelial cells co-culturing attenuated the effects of Ang II. Homocysteine-treated endothelial cells, which are functionally impaired, were less inhibitory of the phenotypic modulation of adventitial fibroblasts. Supplementation of endothelial cells with L-arginine (L-Arg) or 8-bromoguanosine 3',5'-cyclic monophosphate (8-BrcGMP) enhanced the trends, while with L-NG-nitroarginine methyl ester (L-NAME) or 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) the opposite effect was observed. Under the influence of Ang II, adventitial fibroblasts were prone to undergo phenotypic modulation, which was closely related to vascular remodeling. Our study showed that endothelial cells influenced fibroblast phenotypic transformation and such effect would be mediated through the nitric oxide (NO)/cGMP signaling pathway. J. Cell. Biochem. 118: 1921-1927, 2017. © 2017 Wiley Periodicals, Inc.

Trimethylamine N-oxide induces inflammation and endothelial dysfunction in human umbilical vein endothelial cells via activating ROS-TXNIP-NLRP3 inflammasome.

Recent research demonstrates that the choline-derived metabolite trimethylamine-N-oxide (TMAO) levels are strongly associated with atherosclerosis and cardiovascular risks. The NLRP3 inflammasome responds to exogenous and endogenous danger signals involved in the development of atherosclerosis. Moreover, thioredoxin-interactive protein (TXNIP) activation is a key event linked to NLRP3 inflammasome via reactive oxygen species (ROS). Whether TMAO prime NLRP3 inflammasome via ROS-TXNIP pathway remains unclear. This study observed the expression of TXNIP-NLRP3 inflammasome stimulated by TMAO in human umbilical vein endothelial cells (HUVECs), aiming to elucidate the mechanism by which the TMAO may contribute to inflammation and endothelial dysfunction. Our data showed that TMAO significantly triggered oxidative stress and activated TXNIP-NLRP3 inflammasome whereat inflammatory cytokines interleukin (IL)-1ß and IL-18 were released in a dose- and time-dependent manner, but endothelial nitric oxide synthase (eNOS) and production of nitric oxide (NO) were inhibited. Moreover, TMAO-mediated effects were observably reversed by ROS inhibitor N-acetylcysteine (NAC) treatment or siRNA-mediated knockdown TXPIN and NLRP3. Taken together, our results firstly reveal that TMAO induces inflammation and endothelial dysfunction via activating ROS-TXNIP-NLRP3 inflammasome, suggest a likely mechanism for TMAO-dependent enhancement in atherosclerosis and cardiovascular risks.

Hyperuricemia Is an Independent Risk Factor for Erectile Dysfunction.

INTRODUCTION: Hyperuricemia may be related to the development of endothelial dysfunction and cardiovascular diseases. However, the association between hyperuricemia and erectile dysfunction (ED) is not currently clear. AIM: The goal of this study is to investigate the effect of hyperuricemia on erectile function and possible mechanisms. METHODS: Twenty-four 8-week-old male SD rats were randomly divided into 4 groups. Group A (control): Rats received normal saline and served as controls. Group B (hyperuricemia): rats were given oxonic acid 250 mg/kg bw/day through gastric gavage for 4 weeks. Group C (febuxostat): normal rats were treated with 5 mg/kg febuxostat through gastric gavage for 4 weeks. Group D (hyperuricemia + Febuxostat): normal rats were treated with 250 mg/kg bw/day oxonic acid and 5 mg/kg bw/day febuxostat with 1 hour interval for 4 weeks. MEASUREMENTS: The level of serum uric acid, the maximum intracavernosal pressure (ICPmax), mean arterial pressure (MAP), and the expression of endothelial nitric oxide synthase (eNOS), phospho-eNOS, neuronal NOS, Rho-associated protein kinaise (ROCK)1 and ROCK2 and the level of nitric oxide (NO) and reactive oxygen species (ROS) in cavernous tissue were determined. RESULTS: The level of serum uric acid and ROS in hyperuricemic rats was significantly higher than that in the other 3 groups (P < .05). After electrostimulation with 3 and 5 voltage, the ratio of ICPmax/MAP in hyperuricemic rats was significantly less than that in other 3 groups (P < .05), respectively. eNOS, p-eNOS, and nNOS expression in hyperuricemic rats were significantly decreased compared to the other 3 groups (P < .05), respectively. CONCLUSION: Erectile function is impaired by hyperuricemia. The decrease of eNOS, p-eNOS, and nNOS protein expression and increase of ROS in cavernous tissue may be one of the key mechanisms of ED caused by hyperuricemia.

Ketamine Inhalation Ameliorates Ovalbumin-Induced Murine Asthma by Suppressing the Epithelial-Mesenchymal Transition.

BACKGROUND Asthma accounts for 0.4% of all deaths worldwide, a figure that increases annually. Ketamine induces bronchial smooth muscle relaxation, and increasing evidence suggests that its anti-inflammatory properties might protect against lung injury and ameliorate asthma. However, there is a lack of evidence of the usefulness and mechanism of ketamine in acute asthma exacerbation. This study aimed to analyze the therapeutic effects and mechanism of action of ketamine on acute ovalbumin (OVA)-induced murine asthma. MATERIAL AND METHODS In vivo, BALB/c mice with OVA-induced asthma were treated with or without ketamine (25 or 50 mg/mL). Serum, lung sections, and mononuclear cell suspensions from the lung were collected for histological, morphometric, immunofluorescence, microRNA, quantitative polymerase chain reaction, regulatory T cell identification, cytokine, and Western blotting analyses. In vitro, bronchial epithelial cells were cultured to analyze the effect and mechanism of ketamine on epithelial-mesenchymal transition (EMT) and transforming growth factor-ß (TGF-ß) signaling. RESULTS The inhalation of ketamine 25 or 50 mg/mL markedly suppressed OVA-induced airway hyper-responsiveness and airway inflammation, significantly increased the percentage of CD4+CD25+ T cells, and significantly decreased OVA-induced up-regulation of TGF-ß1 and the EMT. MiR-106a was present at higher amounts in OVA-induced lung samples and was suppressed by ketamine treatment. The in vitro results showed that TGF-ß1-induced EMT was suppressed by ketamine via miR-106a level regulation. CONCLUSIONS Ketamine ameliorates lung fibrosis in OVA-induced asthmatic mice by suppressing EMT and regulating miR-106a level, while ketamine inhalation might be a new therapeutic approach to the treatment of allergic asthma.

Icariin combined with breviscapine improves the erectile function of spontaneously hypertensive rats.

INTRODUCTION: The impaired erectile response in spontaneously hypertensive rats (SHR) is caused by increased signaling of RhoA/Rho-kinase and decreased signaling of nitric oxide (NO). Icariin improves erectile function via upregulating multitargets in NO/cyclic guanosine monophosphate (NO/cGMP) pathway, which breviscapine accomplishes by downregulating RhoA/Rho-kinase pathway. AIM: To investigate the effect and mechanism of icariin combined with breviscapine on the erectile function of SHR. METHODS: Five 12-week-old male Wistar-Kyoto (WKY) rats and 20 age-matched male SHR were evenly randomized into WKY rats control group, SHR control group, icariin-treated group, breviscapine-treated group, and combined treatment group treated by vehicle, icariin, breviscapine, and icariin plus breviscapine, respectively, by gavage for four successive weeks. Maximum intracavernosal pressure/mean arterial pressure (ICPmax/MAP) and the expression of endothelial nitric oxide synthase (eNOS), neuronal nitric oxide synthase (nNOS), phosphodiesterase type 5 inhibitors (PDE5), and Rho-associated, coiled-coil containing protein kinase 1 and 2 (ROCK1 and ROCK2) in the cavernous tissues were determined. RESULTS: The ICPmax/MAP in the combined treatment group was significantly increased compared with SHR control group, icariin-treated group, and breviscapine-treated group. The expression of eNOS and nNOS was significantly higher in the combined treatment group than in SHR control group, icariin-treated group, and breviscapine-treated group (P < 0.05). The expression of PDE5 was significantly lower in the icariin-treated group than in SHR control group (P < 0.05). The expression of ROCK1 was significantly lower in the combined treatment group than in other groups (P < 0.05). The expression of ROCK2 was significantly higher in SHR control group than in WKY rats control group, icariin-treated group, and combined treatment group (P < 0.05). Among these groups, the expression of eNOS and nNOS was the strongest, and ROCK1 was the lowest in WKY rats control group. CONCLUSION: Icariin combined with breviscapine has synergistic effects on erectile function of SHR through different signal pathways.

Rare-Earth Lanthanum-Evoked Amorphization and Optimization to Boost Ambient Nitrogen Fixation over Single-Atom Catalysts.

Single-atom catalysts (SACs) have been widely studied in a variety of electrocatalysis. However, its application in the electrocatalytic nitrogen reduction reaction (NRR) field still suffers from unsatisfactory performance, due to the sluggish mass transfer and significant kinetic barriers. Herein, a novel rare-earth-lanthanum-evoked optimization strategy is proposed to boost ambient NRR over SACs. The incorporation of La with a large atomic radius tends to break the atomic long-range order and trigger the amorphization of SACs, endowing a greater density of dangling bonds that could modify affinity for reactants and adsorbates. Moreover, with unique 5d16s2 valence-electron configurations, its presence could further enrich the electron density and enhance the intrinsic activity of single-metal center via the valence orbital coupling. As expected, the La-modified catalyst presents excellent activity toward the electrochemical NRR, delivering a maximum ammonia yield rate of 33.91 µg h-1 mg-1 and a remarkable Faradaic efficiency of 53.82%.

Ischemia‒Reperfusion accelerates neointimal hyperplasia via IL-1ß-mediated pyroptosis after balloon injury in the rat carotid artery.

Background: Ischemia‒reperfusion (IR) is a pathological process that causes secondary damage to blood vessels. However, whether IR can further worsen neointima formation after balloon injury and the detailed mechanism are unclear. Methods: An in vivo model of balloon injury to the rat carotid artery was established to study the effect of IR following balloon injury on neointima formation. Smooth muscle cells (SMCs) were isolated from rat aortas and exposed to hypoxia-reoxygenation to mimic the IR process in vitro. The in vitro cell model was used to investigate the mechanism of IR-mediated neointima formation after balloon injury, which was further confirmed in an in vivo rat model. Results: IR aggravated neointima formation in the rat carotid artery 2 weeks after balloon injury compared with that observed in the absence of balloon injury (P < 0.001). Compared with that of normal SMCs in the rat carotid artery, the expression of IL-1ß, a key proinflammatory cytokine associated with pyroptosis, was increased more than 3-fold in the IR-induced neointima (P < 0.0001) and contributed to the proliferation and migration of rat primary aortic SMCs (P < 0.0001). This process was alleviated by the antioxidant acetylcysteine (NAC), suggesting its partial dependence on intracellular ROS. In the rat model of IR following balloon injury in the carotid artery, the carotid artery that was locally transfected with AAV carrying sh-IL-1ß or sh-caspase-1, which alleviated neointima formation, as indicated by a reduction in intima-media thickness in the rat carotid artery (P < 0.0001). Conclusion: Our results suggested that IR could promote IL-1ß production in SMCs in the carotid artery after balloon injury and aggravate neointimal hyperplasia, which was alleviated by silencing caspase-1/IL-1ß signaling in SMCs in the carotid artery. These results suggest that IL-1ß may be an effective target to combat IR-related neointima formation.

Molecular Imprinting Technology Enables Proactive Capture of Nitrogen for Boosted Ammonia Synthesis under Ambient Conditions.

Electrochemical nitrogen reduction reaction (NRR) is a burgeoning field for green and sustainable ammonia production, in which numerous potential catalysts emerge endlessly. However, satisfactory performances are still not realized under practical applications due to the limited solubility and sluggish diffusion of nitrogen at the interface. Herein, molecular imprinting technology is adopted to construct an adlayer with abundant nitrogen imprints on the electrocatalyst, which is capable of selectively recognizing and proactively aggregating high-concentrated nitrogen at the interface while hindering the access of overwhelming water simultaneously. With this favorable microenvironment, nitrogen can preferentially occupy the active surface, and the NRR equilibrium can be positively shifted to facilitate the reaction kinetics. Approximately threefold improvements in both ammonia production rate (185.7 µg h-1 mg-1 ) and Faradaic efficiency (72.9%) are achieved by a metal-free catalyst compared with the bare one. It is believed that the molecular imprinting strategy should be a general method to find further applicability in numerous catalysts or even other reactions facing similar challenges.

Turning Waste into Wealth: Sustainable Production of High-Value-Added Chemicals from Catalytic Coupling of Carbon Dioxide and Nitrogenous Small Molecules.

Carbon neutrality is one of the central topics of not only the scientific community but also the majority of human society. The development of highly efficient carbon dioxide (CO2) capture and utilization (CCU) techniques is expected to stimulate routes and concepts to go beyond fossil fuels and provide more economic benefits for a carbon-neutral economy. While various single-carbon (C1) and multi-carbon (C2+) products have been selectively produced to date, the scope of CCU can be further expanded to more valuable chemicals beyond simple carbon species by integration of nitrogenous reactants into CO2 reduction. In this Review, research progress toward sustainable production of high-value-added chemicals (urea, methylamine, ethylamine, formamide, acetamide, and glycine) from catalytic coupling of CO2 and nitrogenous small molecules (NH3, N2, NO3-, and NO2-) is highlighted. C-N bond formation is a key mechanistic step in N-integrated CO2 reduction, so we focus on the possible pathways of C-N coupling starting from the CO2 reduction and nitrogenous small molecules reduction processes as well as the catalytic attributes that enable the C-N coupling. We also propose research directions and prospects in the field, aiming to inspire future investigations and achieve comprehensive improvement of the performance and product scope of C-N coupling systems.

Development of a Hepatic VX2 carcinoma model in rabbits using an improved minimally invasive method and evaluation with imaging examinations.

Context: The hepatic VX2 carcinoma model in rabbits has been widely used in interventional diagnosis and treatment research for hepatocellular carcinoma (HCC). However, traditional methods for developing this model all have their shortcomings. Aims: To develop an improved method to construct an animal model of hepatic VX2 carcinoma. Settings and Design: The puncture technique was used to obtain the VX2 tumor tissue. A tumor puncture-inoculation kit was designed and modified to implant the tumor tissue into the recipient rabbit's liver. Methods and Material: 18 New Zealand white rabbits were implanted with VX2 tumor tissue using the improved tumor puncture-inoculation kit under ultrasound guidance. Ultrasonography, contrast-enhanced computerized tomography, magnetic resonance imaging, and digital subtraction angiography were performed to evaluate tumor formation and imaging characteristics. Statistical Analysis: Statistical analysis was performed using SPSS software. Two groups were compared using Student's t-test analysis. Results: All rabbits tolerated VX2 tumor tissue implantation successfully. 17 out of the 18 experimental rabbits developed liver tumors, and one rabbit had abdominal tumor metastasis. The average volume of tumors was 39.47 mm3 and 460.1 mm3 (P < 0.001) on the 7th and 14th days after modeling, respectively. Imageological diagnosis showed that all tumors had abundant blood supply and typical imaging characteristics. Conclusions: This improved modeling method is easy to operate and less traumatic, with a high tumor formation rate, low metastasis rate, prominent tumor imaging characteristics, and high detection rate, which is expected to become a promising method for constructing rabbit liver tumor model.

AGEs/RAGE Promote Osteogenic Differentiation in Rat Bone Marrow-Derived Endothelial Progenitor Cells via MAPK Signaling.

Systemic vascular impairment is the most common complication of diabetes. Advanced glycation end products (AGEs) can exacerbate diabetes-related vascular damage by affecting the intima and media through a variety of mechanisms. In the study, we demonstrated that AGEs and their membrane receptor RAGE could induce the differentiation of EPCs into osteoblasts under certain circumstances, thereby promoting accelerated atherosclerosis. Differentiation into osteoblasts was confirmed by positive staining for DiI-acetylated fluorescently labeled low-density lipoprotein and FITC-conjugated Ulex europaeus agglutinin. During differentiation, expression of receptor for AGE (RAGE) was significantly upregulated. This upregulation was attenuated by transfection with RAGE-targeting small interfering (si)RNA. siRNA-mediated knockdown of RAGE expression significantly inhibited the upregulation of AGE-induced calcification-related proteins, such as runt-related transcription factor 2 (RUNX2) and osteoprotegerin (OPG). Additional experiments showed that AGE induction of EPCs significantly induced ERK, p38MAPK, and JNK activation. The AGE-induced upregulation of osteoblast proteins (RUNX2 and OPG) was suppressed by treatment with a p38MAPK inhibitor (SB203580) or JNK inhibitor (SP600125), but not by treatment with an ERK inhibitor (PD98059), which indicated that AGE-induced osteoblast differentiation from EPCs may be mediated by p38MAPK and JNK signaling, but not by ERK signaling. These data suggested that AGEs may bind to RAGE on the EPC membrane to trigger differentiation into osteoblasts. The underlying mechanism appears to involve the p38MAPK and JNK1/2 pathways, but not the ERK1/2 pathway.

Involvement of endothelial progenitor cells in blood flow recovery through activation of the Wnt/ß-catenin signaling pathway and inhibition of high oxidative stress in diabetic hindlimb ischemic rats.

BACKGROUND: Diabetes mellitus (DM) often causes stenosis and occlusion of hindlimb blood vessels, which are also the main cause for hindlimb ischemia in elderly people. OBJECTIVES: To investigate the therapeutic effect of endothelial progenitor cell (EPC) transplantation on diabetic hindlimb ischemia. MATERIAL AND METHODS: Endothelial progenitor cells were separated, labeled with PKH-26 and transplanted into rat models (107 cells/100 g). Dichlorodihydrofluorescein diacetate (DCFH-DA) was used to detect any oxidative stress. Streptozotocin (STZ) was injected to establish a diabetic rat model and hindlimb ischemia model was established via operation. Western blotting was used to detect total ß-catenin (T-ß-catenin) and non-phospho-ß-catenin (NP-ß-catenin) levels. The malondialdehyde (MDA), superoxide dismutase (SOD), Wnt3a, Wnt5a and Wnt7a levels were detected using enzyme-linked immunosorbent assay (ELISA). Oxidative stress was measured using DCFH-DA and dihydroethidium (DHE). The endothelial biomarker CD31 was observed to highlight vessels, and PKH-26 to trace migration/adhesion of EPCs. RESULTS: Endothelial progenitor cells were successfully isolated and identified, and diabetic hindlimb ischemic rat models were created. Tempol remarkably improved blood flow in diabetic hindlimb ischemic rats compared to DM+EPCs rats at 14 days (p < 0.001) and 28 days post-operation (p < 0.001). High oxidative stress was observed in diabetic hindlimb ischemic rats. Tempol significantly inhibited oxidative stress levels in diabetic hindlimb ischemic rats. Furthermore, Tempol significantly promoted angiogenesis in diabetic hindlimb ischemic rats compared to DM+EPCs rats. The ß-catenin inhibitor, XAV (DM+EPCs+Tempol+XAV group), significantly suppressed blood flow recovery and angiogenesis in diabetic hindlimb ischemic rats when compared to the DM+EPCs+Tempol group at 14 days (p = 0.026) and 28 days (p < 0.001). The XAV remarkably reduced T-ß-catenin (p < 0.001) and N-ß-catenin (p = 0.030) levels in Tempol-treated diabetic hindlimb ischemic rats, as compared to the DM+EPCs+Tempol group. The Wnt5a participated in the pathology of diabetic hindlimb ischemia. CONCLUSIONS: There are high oxidative stress levels in both EPCs in high-glucose environments and diabetic hindlimb ischemia, which can lead to limited blood flow recovery. The high oxidative stress caused the inhibition of Wnt/ß-catenin signaling pathway, leading to limited blood flow recovery in diabetic hindlimb ischemia. At the same time, Wnt5a participated in the EPC-mediated blood flow recovery.

[Role of Rac1 activation in platelet derived growth factor-BB induced proliferation and migration in rat aortic smooth muscle cells].

OBJECTIVE: To explore the impact of Rac1 activation on the proliferation and migration under the stimulation of PDGF-BB (platelet derived growth factor-BB). METHODS: The inhibitory effects of Rac1 inhibitor (NSC23766) and Rac1siRNA on the proliferation and migration of vascular smooth muscle cell under the stimulation of PDGF-BB were measured by CCK8 assay and Transwell chamber. The time characteristics of Rac1 activity and pi-JNK expression under the stimulation of PDGF-BB was detected by GST pulldown assay and Western blot. And the inhibitory effects of NSC23766 and Rac1siRNA on the Rac1 activation and pi-JNK expression were also measured. RESULTS: Migration and proliferation of vascular smooth muscle cell increased significantly after the stimulation of PDGF-BB (50 µg/L). Migration and proliferation was inhibited significantly after a pretreatment of Rac1siRNA and various concentrations of NSC23766 (25, 50, 100 µg/L). After the stimulation of PDGF-BB, the expression of pi-JNK and Rac1 activity increased over time. Rac1-GTP peaked at 5 minutes and pi-JNK at 15 minute. The expressions of pi-JNK at 15 minutes and Rac1-GTP at 5 minutes were inhibited significantly by Rac1siRNA and NSC23766 in a concentration-dependent manner. CONCLUSION: JNK phosphorylation is controlled by Rac1 activation. And Rac1 activation play a pivotal role in the migration and proliferation of aortic smooth muscle cell under the stimulation of PDGF-BB.

AGEs-Induced Calcification and Apoptosis in Human Vascular Smooth Muscle Cells Is Reversed by Inhibition of Autophagy.

Vascular calcification (VC) in macrovascular and peripheral blood vessels is one of the main factors leading to diabetes mellitus (DM) and death. Apart from the induction of vascular calcification, advanced glycation end products (AGEs) have also been reported to modulate autophagy and apoptosis in DM. Autophagy plays a role in maintaining the stabilization of the external and internal microenvironment. This process is vital for regulating arteriosclerosis. However, the internal mechanisms of this pathogenic process are still unclear. Besides, the relationship among autophagy, apoptosis, and calcification in HASMCs upon AGEs exposure has not been reported in detail. In this study, we established a calcification model of SMC through the intervention of AGEs. It was found that the calcification was upregulated in AGEs treated HASMCs when autophagy and apoptosis were activated. In the country, AGEs-activated calcification and apoptosis were suppressed in Atg7 knockout cells or pretreated with wortmannin (WM), an autophagy inhibitor. These results provide new insights to conduct further investigations on the potential clinical applications for autophagy inhibitors in the treatment of diabetes-related vascular calcification.