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The microvascular network plays an important role in providing nutrients to the injured tissue and exchanging various metabolites. However, how to achieve efficient penetration of the injured tissue is an important bottleneck restricting the reconstruction of microvascular network. Herein, the hydrogel precursor solution can efficiently penetrate the damaged tissue area, and ultrasound triggers the release of thrombin from liposomes in the solution to hydrolyze fibrinogen, forming a fibrin solid hydrogel network in situ with calcium ions and transglutaminase as catalysts, effectively solving the penetration impedance bottleneck of damaged tissues and ultimately significantly promoting the formation of microvascular networks within tissues. First, the fibrinogen complex solution is effectively permeated into the injured tissue. Second, ultrasound triggered the release of calcium ions and thrombin, activates transglutaminase, and hydrolyzes fibrinogen. Third, fibrin monomers are catalyzed to form fibrin hydrogels in situ in the damaged tissue area. In vitro studies have shown that the fibrinogen complex solution effectively penetrated the artificial bone tissue within 15 s after ultrasonic triggering, and formed a hydrogel after continuous triggering for 30 s. Overall, this innovative strategy effectively solved the problem of penetration resistance of ultrasound‐triggered hydrogels in the injured tissues, and finally activates in situ microvascular networks regeneration. [ABSTRACT FROM AUTHOR]

With the development of science and technology, data plays an increasingly important role in our daily life. Therefore, much attention has been paid to the field of data mining. Data classification is the premise of data mining, and how well the data is classified directly affects the performance of subsequent models. In particular, in the medical field, data classification can help accurately determine the location of patients' lesions and reduce the workload of doctors in the treatment process. However, medical data has the characteristics of high noise, strong correlation, and high data dimension, which brings great challenges to the traditional classification model. Therefore, it is very important to design an advanced model to improve the effect of medical data classification. In this context, this paper first introduces the structure and characteristics of the convolutional neural network (CNN) model and then demonstrates its unique advantages in medical data processing, especially in data classification. Secondly, we design a new kind of medical data classification model based on the CNN model. Finally, the simulation results show that the proposed method achieves higher classification accuracy with faster model convergence speed and the lower training error when compared with conventional machine leaning methods, which has demonstrated the effectiveness of the new method in respect to medical data classification. [ABSTRACT FROM AUTHOR]

Microvascular lesion in diabetic peripheral arterial disease (PAD) still cannot be resolved by current surgical and interventional technique. Endothelial cells have the therapeutic potential to cure microvascular lesion. To evaluate the efficacy and immune-regulatory impact of intra-arterial infusion of autologous CD133+ cells, we recruited 53 patients with diabetic PAD (27 of CD133+ group and 26 of control group). CD133+ cells enriched from patients’ PB-MNCs were reinfused intra-arterially. The ulcer healing followed up till 18 months was 100% (3/3) in CD133+ group and 60% (3/5) in control group. The amputation rate was 0 (0/27) in CD133+ group and 11.54% (3/26) in control group. Compared with the control group, TcPO2 and ABI showed obvious improvement at 18 months and significant increasing VEGF and decreasing IL-6 level in the CD133+ group within 4 weeks. A reducing trend of proangiogenesis and anti-inflammatory regulation function at 4 weeks after the cells infusion was also found. These results indicated that autologous CD133+ cell treatment can effectively improve the perfusion of morbid limb and exert proangiogenesis and anti-inflammatory immune-regulatory impacts by paracrine on tissue microenvironment. The CD133+ progenitor cell therapy may be repeated at a fixed interval according to cell life span and immune-regulatory function. [ABSTRACT FROM AUTHOR]

Background/Aims: Atherosclerosis is associated with dysfunction of endothelial progenitor cells (EPCs). Tripterine, a chemical compound derived from the Chinese medicinal plant Tripterygium wilfordii Hook, displays anti-inflammatory properties in several animal models. We hypothesized that tripterine can improve EPC function and thus the efficiency of EPC transplantation. Methods and Results: Tripterine preconditioning (2.5 μM, 4 h) improved EPC proliferation, tube formation, migration, and adhesion, and reduced apoptosis in cells cultured in ox-LDL (200 ug/ml). Tripterine restored integrin-linked kinase (ILK) levels downregulated by ox-LDL in EPCs, suggesting the involvement of the ILK/Akt pathway. Small interfering RNA-mediated depletion of ILK and dominant-negative ILK transduction inhibited the phosphorylation of the ILK downstream signaling targets protein kinase B/ Akt and glycogen synthase kinase 3-beta (GSK-3β), and reduced β-catenin and cyclin D1 expression. In atherosclerotic mice injected with green fluorescent protein-labeled EPCs to evaluate EPC function, tripterine decreased aortic lesions and plaque deposition, and injection of tripterine-treated EPCs restored ILK levels. Conclusion: The present results suggest that tripterine improves vascular function in atherosclerosis by enhancing EPC function through a mechanism involving the ILK signaling pathway. [ABSTRACT FROM AUTHOR]

The dysfunction of endothelial progenitor cells (EPCs) limits their potential for the treatment of ischemia and atherosclerosis. Therefore, we investigated the effect of tripterine on EPC function and examined the underlying mechanisms. The effect of tripterine, an active component of Tripterygium wilfordii Hook, on the enhancement of EPC function and the efficiency of EPC transplantation was investigated in vitro and in vivo. Treatment of EPCs with tripterine at 2.5 µM for 4 h inhibited oxidized low-density lipoprotein (ox-LDL) induced ROS production, cell apoptosis, and cell senescence and improved the migration and tube formation capacities of EPCs treated with ox-LDL (200 µg/ml). In vivo studies showed that tripterine conditioning of EPCs administered to ischemic foci improved blood perfusion and microvascular density in a mouse hindlimb ischemia model. Examination of the underlying mechanisms indicated that the effect of tripterine is mediated by the induction of heat shock protein 32 expression and the inhibition of JNK activation. The present results are of clinical significance because they suggest the potential of tripterine as a therapeutic agent to improve the efficacy of EPC transplantation for the treatment of ischemic diseases. J. Cell. Physiol. 230: 1139-1147, 2015. © 2014 Wiley Periodicals, Inc., A Wiley Company [ABSTRACT FROM AUTHOR]

Background: Dysfunction of circulating endothelial progenitor cells (EPCs) is associated with the onset of cardiovascular disorders. Circulating microRNAs (miRNAs) have been recognized as novel biomarkers and potential therapeutic targets. Here, we examined the role of miR-26a overexpression in atherosclerosis and explored the underlying mechanisms. Methods: EPCs were obtained from patients with atherosclerosis and healthy controls. Bone marrow (BM)-derived EPCs were exposed to hypoxia to mimic the atherosclerotic environment and miR-26a, EphA2 and p38 MAPK levels were measured by qRT-PCR and western blotting, and VEGF levels were determined by enzyme linked immunosorbent assay. Cell viability was assessed using the MTT assay, and luciferase activity assays confirmed EphA2 as a target of miR-26a. Results: MiR-26a was overexpressed in patients with atherosclerosis and associated with EPC dysfunction. EphA2 was identified as a direct target of miR-26a. Overexpression of miR-26a downregulated EphA2 and impaired EPC function, whereas knockdown of miR-26a upregulated EphA2 and reversed hypoxia-induced EPC dysfunction. MiR-26a overexpression or knockdown modulated the activity of p38 MAPK and the levels of VEGF in EPCs. Conclusions: The role of miR-26a in atherosclerosis is mediated by its target EphA2 via a mechanism involving the p38 MAPK/VEGF pathway. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Small GTPases (guanosine triphosphate, GTP) are involved in many critical cellular processes, including inflammation, proliferation, and migration. GTP loading and isoprenylation are two important post-translational modifications of small GTPases, and are critical for their normal function. In this study, we investigated the role of post-translational modifications of small GTPases in regulating endothelial cell inflammatory responses and junctional integrity. Methods and Results: Confluent human umbilical vein endothelial cell (HUVECs ) treated with atorvastatin demonstrated significantly decreased lipopolysaccharide (LPS)-mediated IL-6 and IL-8 generation. The inhibitory effect of atorvastatin (Atorva) was attenuated by co-treatment with 100 µM mevalonate (MVA) or 10 µM geranylgeranyl pyrophosphate (GGPP), but not by 10 µM farnesyl pyrophosphate (FPP). Atorvastatin treatment of HUVECs produced a time-dependent increase in GTP loading of all Rho GTPases, and induced the translocation of small Rho GTPases from the cellular membrane to the cytosol, which was reversed by 100 µM MVA and 10 µM GGPP, but not by 10 µM FPP. Atorvastatin significantly attenuated thrombin-induced HUVECs permeability, increased VE-cadherin targeting to cell junctions, and preserved junction integrity. These effects were partially reversed by GGPP but not by FPP, indicating that geranylgeranylation of small GTPases plays a major role in regulating endothelial junction integrity. Silencing of small GTPases showed that Rho and Rac, but not Cdc42, play central role in HUVECs junction integrity. Conclusions: In conclusion, our studies show that post-translational modification of small GTPases plays a vital role in regulating endothelial inflammatory response and endothelial junction integrity. Atorvastatin increased GTP loading and inhibited isoprenylation of small GTPases, accompanied by reduced inflammatory response and preserved cellular junction integrity. [ABSTRACT FROM AUTHOR]

Abstract: Hsp90 interacts with proteins that mediate signaling pathways involved in the regulation of essential processes such as proliferation, cell cycle control, angiogenesis and apoptosis. Hsp90 inhibition is therefore an attractive strategy for blocking abnormal pathways that are crucial for cancer cell growth. In the present study, the role of Hsp90 in human breast cancer MCF-7 cells was examined by stably silencing Hsp90 gene expression with an Hsp90-silencing vector (Hsp90-shRNA). RT-PCR and Western blot analyses showed that Hsp90-shRNA specifically and markedly down-regulated Hsp90 mRNA and protein expression. NF-kB and Akt protein levels were down-regulated in Hsp90-shRNA transfected cells, indicating that Hsp90 knockout caused a reduction of survival factors and induced apoptosis. Treatment with Hsp90-shRNA significantly increased apoptotic cell death and caused cell cycle arrest in the G1/S phase in MCF-7 cells, as shown by flow cytometry. Silencing of Hsp90 also reduced cell viability, as determined by MTT assay. In vivo experiments showed that MCF-7 cells stably transfected with Hsp90-shRNA grew slowly in nude mice as compared with control groups. In summary, the Hsp90-shRNA specifically silenced the Hsp90 gene, and inhibited MCF-7 cell growth in vitro and in vivo. Possible molecular mechanisms underlying the effects of Hsp90-shRNA include the degradation of Hsp90 breast cancer-related client proteins, the inhibition of survival signals and the upregulation of apoptotic pathways. shRNA-mediated interference may have potential therapeutic utility in human breast cancer. [Copyright &y& Elsevier]

Background: Cyclosporine A (CsA) is routinely used to treat patients with steroid-refractory acute severe ulcerative colitis (ASUC). Here, we studied the underlying mechanisms of CsA-mediated alleviation in ASUC patients., Methods: Neutrophil functions including expression of cytokines, apoptosis, and migration were measured by qRT-PCR, flow cytometry, and Transwell assay. Dynamic changes of glycolysis and tricarboxylic acid (TCA) cycle were measured by a Seahorse extracellular flux analyzer. Gene differences were determined and verified by RNA sequencing, qRT-PCR, and Western blotting. Small interfering RNA and inhibitors were used to knock down Sirtuin 6 (SIRT6) in HL-60 cells and block expression of SIRT6, hypoxia-inducible factor-1α (HIF-1α), and pyruvate dehydrogenase lipoamide kinase isozyme 4 (PDK4) in neutrophils., Results: We found that HIF-1α expression and glycolysis significantly increased, while the release of IL-8, myeloperoxidase (MPO) and reactive oxygen species (ROS), the apoptosis, and ability of migration markedly decreased in neutrophils of ASUC patients who responded to CsA (Response group) compared with those who did not respond to CsA (Nonresponse group). We also observed that CsA-induced functional alternation of neutrophils was initiated through suppressing SIRT6 expression, which is responsible for expression of the downstream signaling molecules (e.g., HIF-1α, PFKFB3) and PDK4 ubiquitination, leading to fueling neutrophil glycolysis and TCA cycle. Furthermore, blockage of SIRT6 signaling demonstrated to be the same functional changes as CsA to decrease the migration of neutrophils., Conclusions: The data reveal a novel mechanism of CsA in alleviating ASUC by promoting neutrophil HIF-1α expression and restricting excessive neutrophil activation in a SIRT6-HIF-1α-glycolysis axis, suggesting SIRT6 as a candidate target for maintaining mucosal homeostasis and treating intestinal inflammation., (© 2021 The Authors. Clinical and Translational Medicine published by John Wiley & Sons Australia, Ltd on behalf of Shanghai Institute of Clinical Bioinformatics.)

Microvascular lesion in diabetic peripheral arterial disease (PAD) still cannot be resolved by current surgical and interventional technique. Endothelial cells have the therapeutic potential to cure microvascular lesion. To evaluate the efficacy and immune-regulatory impact of intra-arterial infusion of autologous CD133(+) cells, we recruited 53 patients with diabetic PAD (27 of CD133(+) group and 26 of control group). CD133(+) cells enriched from patients' PB-MNCs were reinfused intra-arterially. The ulcer healing followed up till 18 months was 100% (3/3) in CD133(+) group and 60% (3/5) in control group. The amputation rate was 0 (0/27) in CD133(+) group and 11.54% (3/26) in control group. Compared with the control group, TcPO2 and ABI showed obvious improvement at 18 months and significant increasing VEGF and decreasing IL-6 level in the CD133(+) group within 4 weeks. A reducing trend of proangiogenesis and anti-inflammatory regulation function at 4 weeks after the cells infusion was also found. These results indicated that autologous CD133(+) cell treatment can effectively improve the perfusion of morbid limb and exert proangiogenesis and anti-inflammatory immune-regulatory impacts by paracrine on tissue microenvironment. The CD133(+) progenitor cell therapy may be repeated at a fixed interval according to cell life span and immune-regulatory function.

Endothelial damage is strongly associated with cardiovascular diseases such as atherosclerosis. Bone marrow-derived endothelial progenitor cells (EPCs) play an important role in the maintenance of endothelial homeostasis and contribute to re-endothelialization of injured vessels as well as revascularization of ischemic tissues. MicroRNAs (miRNAs) have been reported to regulate EPC biological functions. In this study, we found that EPCs of atherosclerosis patients and EPCs exposed to hypoxia have increased expression of miRNA-21 (miR-21) as well as diminished ability to proliferate. MiR-21 knockdown rescued hypoxia-induced growth arrest in EPCs. Next, we used a luciferase reporter assay to demonstrate that miR-21 downregulates the expression of WW domain-containing protein 1 (WWP1), a negative regulator of TGFβ signaling, by directly targeting the 3'-UTR of WWP1. Finally, miR-21 overexpression or WWP1 knockdown in EPCs significantly activates the TGFβ signaling pathway and inhibits cell proliferation. Taken together, our results indicate that miR-21 suppresses EPC proliferation by activating the TGFβ signaling pathway via downregulation of WWP1. These findings may help the development of strategies to enhance the vitality of EPCs for therapeutic applications.