The stimulatory effects of eNOS/F92A-Cav1 on NO production and angiogenesis in BMSCs

Mesenchymal stem cell-derived extracellular vesicles prevent the formation of pulmonary arterial hypertension through a microRNA-200b-dependent mechanism

BACKGROUND

Bone marrow mesenchymal stem cell-derived extracellular vesicles (BMSC-EVs) have been highly studied with their critical roles as carriers of therapeutic targets such as microRNAs (miRNAs) in the treatment of human diseases, including pulmonary arterial hypertension (PAH). Herein, we tried to study the potential of BMSC-EVs to deliver miR-200b for the regulation of macrophage polarization in PAH.

METHODS

Rat models of PAH were induced with monocrotaline treatment, followed by miR-200b expression detection in lung tissues, pulmonary artery smooth muscle cells (PASMCs) and macrophages. miR-200b-containing BMSCs or miR-200b-deficient BMSCs were selected to extract EVs. Then, we assessed the changes in rats with PAH-associated disorders as well as in vitro macrophage polarization and the functions of PASMCs after treatment with BMSC-EVs. Moreover, the interaction between miR-200b, phosphodiesterase 1 A (PDE1A) was identified with a luciferase assay, followed by an exploration of the downstream pathway, cAMP-dependent protein kinase (PKA).

RESULTS

miR-200b was reduced in lung tissues, PASMCs and macrophages of rats with PAH-like pathology. BMSC-EVs transferred miR-200b into macrophages, and subsequently accelerated their switch to the M2 phenotype and reversed the PAH-associated disorders. Furthermore, miR-200b carried by BMSC-EVs induced PKA phosphorylation by targeting PDE1A, thereby expediting macrophage polarization.

CONCLUSION

Our current study highlighted the inhibitory role of BMSC-EV-miR-200b in PAH formation.

DIA proteomics identified the potential targets associated with angiogenesis in the mammary glands of dairy cows with hemorrhagic mastitis

Hemorrhagic mastitis (HM) in dairy cows caused great economic losses in the dairy industry due to decreased milk production and increased costs associated with cattle management and treatment. However, the pathological and molecular mechanisms of HM are not well-understood. The present study aimed to investigate differentially expressed proteins (DEPs) associated with HM according to data-independent acquisition (DIA) proteomics. Compared to the mammary glands of healthylactating Holstein cows (Control, C group), the pathology of the HM group displayed massive alveolar infiltration of hemocytes and neutrophils, and the blood vessels, including arteriole, venules and capillaries were incomplete and damaged, with a loss of endothelial cells. DIA proteomics results showed that a total of 3,739 DEPs and 819 biological process terms were screened in the HM group. We focused on the blood, permeability of blood vessel, vascular and angiogenesis of mammary glands, and a total of 99 candidate DEPs, including 60 up- and 39 down-regulated DEPs, were obtained from the Gene Ontology (GO) and Pathway enrichment analyses. Phenotype prediction and function analysis of the DEPs revealed that three DEPs, particularly Caveolin-1(CAV1), were participated in the regulation of angiogenesis. Immunohistochemical and immunofluorescence staining showed that the CAV1 protein was present mainly in the mammary epithelial cells, vascular endothelial cells and vascular smooth muscle cells. The expression level of CAV1 mRNA and protein in the HM group was significantly down-regulated. The results will be helpful to the further understanding of the pathological and molecular mechanisms of HM in dairy cows.

rBMSC/Cav-1F92A Mediates Oxidative Stress in PAH Rat by Regulating SelW/14-3-3η and CA1/Kininogen Signal Transduction

Background/Objectives

Carbonic anhydrase 1 (CA1)/kininogen and selenoprotein W (SelW)/14-3-3η signal transduction orchestrate oxidative stress, which can also be regulated by nitric oxide (NO). The mutated caveolin-1 (Cav-1^F92A) gene may enhance NO production. This study explored the effect of Cav-1^F92A-modified rat bone marrow mesenchymal stem cells (rBMSC/Cav-1^F92A) on oxidative stress regulation through CA1/kininogen and SelW/14-3-3η signal transduction in a rat model of monocrotaline- (MCT-) induced pulmonary arterial hypertension (PAH).

Method

PAH was induced in rats through the subcutaneous injection of MCT. Next, rBMSC/Vector (negative control), rBMSC/Cav-1, rBMSC/Cav-1^F92A, or rBMSC/Cav-1^F92A+L-NAME were administered to the rats. Changes in pulmonary hemodynamic and vascular morphometry and oxidative stress levels were evaluated. CA1/kininogen and SelW/14-3-3η signal transduction, endothelial nitric oxide synthase (eNOS) dimerization, and eNOS/NO/sGC/cGMP pathway changes were determined through real-time polymerase chain reaction, Western blot, or immunohistochemical analyses.

Results

In MCT-induced PAH rats, rBMSC/Cav-1^F92A treatment reduced right ventricular systolic pressure, vascular stenosis, and oxidative stress; downregulated CA1/kininogen signal transduction; upregulated SelW/14-3-3η signal transduction; and reactivated the NO pathway.

Conclusions

In a rat model of MCT-induced PAH, rBMSC/Cav-1^F92A reduced oxidative stress by regulating CA1/kininogen and SelW/14-3-3η signal transduction.

Inhibition of Obtusifolin on retinal pigment epithelial cell growth under hypoxia

AIM

To explore the effect of Obtusifolin on retinal pigment epithelial cell growth under hypoxia.

METHODS

In vitro chemical hypoxia model of ARPE-19 cells was established using cobalt chloride (CoCl₂). Cell viability was tested by cell counting kit-8 (CCK-8) assay. Western blot and real-time quantitative polymerase chain reaction were applied to detect proteins and mRNAs respectively. Flow cytometry was used to examine the cell cycle. Secretion of vascular endothelial growth factor (VEGF) was tested by using enzyme linked immunosorbent assay (ELISA).

RESULTS

Under the chemical hypoxia model established by CoCl₂, hypoxia inducible factor-1α (HIF-1α) mRNA and protein levels was up-regulated. Cell viability was increased and the proportion of S phase was higher. Obtusifolin could reduce cell viability under hypoxic conditions and arrest cells in G1 phase. Obtusifolin reduced the expression of Cyclin D1 and proliferating cell nuclear antigen (PCNA) in the hypoxic environment and increased the expression of p53 and p21. The levels of VEGF, VEGFR2 and eNOS proteins and mRNA were significantly increased under hypoxia while Obtusifolin inhibited the increasing.

CONCLUSION

Obtusifolin can inhibit cell growth under hypoxic conditions and down-regulate HIF-1/VEGF/eNOS secretions in ARPE-19 cells.

MicroRNA-155 induces protection against cerebral ischemia/reperfusion injury through regulation of the Notch pathway in vivo

microRNA (miR)-155 has been demonstrated to participate in the regulation of endothelium during cerebral ischemia. In the present study, it was aimed to investigate the molecular mechanism of miR-155 in the regulation of cerebral ischemia/reperfusion (I/R) injury with middle cerebral artery occlusion (MCAO) in mice. The MCAO model was established in C57BL/6 mice. Transfection of miR-155 mimics and miR-155 inhibitors was performed to alter the expression of miR-155. The level of miR-155 was measured by RT-qPCR analysis. The western blotting results demonstrated that deletion of miR-155 increased the expression of Notch1, intracellular Notch receptor domain (NICD) and hairy and enhancer of split-1 (Hes1) levels. In addition, the percentage of terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling-positive cells and caspase-3 levels were decreased following treatment with a miR-155 inhibitor compared with the Pre-IR group. Notably, disrupting miR-155 also increased nitric oxide (NO) production and the expression of endothelial NO synthase (eNOS), leading to downregulation of brain water content and Evans blue levels. However, overexpression of miR-155 restored all these changes to similar levels observed in the cerebral I/R injury group. The expressions of Notch1, NICD and Hes1 were also decreased to the cerebral I/R injury condition. In conclusion, a novel mechanism was identified for abrogating normal NO production and eNOS expression via the aberrant expression of the Notch signaling pathway, a mechanism that may be modulated by miR-155. Together, these results reveal important functions of miR-155 in regulating the Notch signaling pathway of the nervous system, and a potential role for miR-155 as a crucial therapy target for cerebral stroke.

rBMSCs/ITGA5B1 Promotes Human Vascular Smooth Muscle Cell Differentiation via Enhancing Nitric Oxide Production

Background and Objectives

Previous studies have shown that integrins alpha5beta1 (ITGA5B1) gene-modified rat bone marrow mesenchymal stem cells (rBMSCs) could prevent cell anoikis and increase the nitric oxide (NO) production. Here we examined the capability of rBMSCs/ITGA5B1 on the phenotype modulation of Human Pulmonary Artery Smooth Muscle Cell (HPASMC) in vitro.

Methods and Results

The synthetic (dedifferentiated) phenotype of HPASMC was induced by monocrotaline (MCT, 1μM) for 24 h and then co-cultured with rBMSCs/ITGA5B1 in a transwell culture system. The activation of NO/cGMP (nitric oxide/Guanosine-3', 5'-cyclic monophosphate) signaling was investigated in HPASMC. The changes of pro-inflammatory factors, oxidative stress, vasodilator, vasoconstrictor, contractile and synthetic genes, and the morphological changes of HPASMC were investigated. The results of this study showed that the NO/cGMP signal, endothelial nitric oxide synthase (eNOS) expression, the expression of the vasoprotective genes heme oxygenase-1 (HMOX1) and prostaglandin-endoperoxide synthase 2 (PTGS2) were increased, but the expression of transforming growth factor-β1 (TGF-β1), CCAAT/enhancer-binding proteins delta (Cebpd), Krüppel-like factor 4 (KLF4), and activating transcription factor 4 (ATF4) were reduced in MCT treated HPASMC co-cultured with rBMSCs/ITGA5B1. The synthetic smooth muscle cells (SMCs) phenotype markers thrombospondin-1, epiregulin and the vasoconstrictor endothelin (ET)-1, thromboxane A2 receptor (TbxA2R) were down-regulated, whereas the contractile SMCs phenotype marker transgelin expression was up-regulated by rBMSCs/ITGA5B1. Furthermore, rBMSCs/ITGA5B1 promoted the morphological restoration from synthetic (dedifferentiation) to contractile (differentiation) phenotype in MCT treated HPASMC.

Conclusions

rBMSCs/ITGA5B1 could inhibit inflammation and oxidative stress related genes to promote the HPASMC cell differentiation by activation NO/cGMP signal.

Integrin alpha5beta1 suppresses rBMSCs anoikis and promotes nitric oxide production

BACKGROUND

Cell based therapy has been heralded as a novel, promising therapeutic strategy for cardiovascular diseases including pulmonary arterial hypertension (PAH). However, the low survival rate after transplantation due to cell death via anoikis is a major obstacle in stem cell therapy. Cells adhesion via Integrin alpha5beta1 (ITGA5B1) has a tendency to exert higher maximum forces. The present study aimed to evaluate the potential protective effect of ITGA5B1 on rat bone marrow mesenchymal stem cells (rBMSCs) from anoikis.

METHODS

Mononuclear cells were isolated by density gradient centrifugation with Ficoll, and rBMSCs cell surface markers were evaluated by flow cytometry. Osteogenic and adipocyte differentiation was determined by Alizarin Red S and Oil Red O staining respectively. The expression of Integrin A5 (ITGA5), Integrin B1 (ITGB1), eNOS and actived-caspase-3 mRNA or protein was confirmed by qPCR and western-blot. Cell adhesion, cell viability, anoikis and the migration of rBMSCs were also evaluated. Nitric oxide (NO) production was detected by the greiss assay.

RESULTS

Co-infected with Integrin A5 and B1 lentivirus to rBMSCs increased ITGA5 and ITGB1 mRNA and protein expression. ITGA5B1 enhanced the cell adhesion, cell viability, cell migration and NO production but reduced the cell anoikis in rBMSCs/ITGA5B1 groups.

CONCLUSION

Transduction of rat rBMSCs with ITGA5B1 lentivirus could prevent cell anoikis and increase NO production.

Pathway-focused PCR array profiling of CAL-27 cell with over-expressed ZNF750

Zinc-finger protein 750 (ZNF750) is the potential anti-cancer gene in oral squamous cell carcinoma (OSCC). The present study was to investigate the expression changes of ZNF750 in OSCC tissue and to reveal the induction of altered mRNA expression profiles caused by over-expressed ZNF750 in CAL-27 cell. The expression level of ZNF750 in tissue specimens from OSCC patients was detected by immunohistochemistry. Gene expression profiling was performed using Human Signal Transduction PathwayFinder RT² Profiler™ PCR Array. The expression changes of 84 key genes representing 10 signal transduction pathways in human following over-expressed ZNF750 in CAL-27 cell was examined. The expression of ZNF750 protein was reduced in OSCC tissues. The R² PCR Array analysis revealed that 39 of the 84 examined genes that changed at least a two-fold between control and ZNF750 groups. These genes related to oxidative stress, WNT, JAK/STAT, TGFβ, NF-kappaB (NFκB), p53, Notch, Hedgehog, PPAR and Hypoxia signaling. ZNF750 could inhibit the candidate genes ATF4, SQSTM1, HMOX1, CCND1, TNF-alpha, TNFSF10 and FOSL1 but activate CDKN1A and EMP1. Our studies suggest that ZNF750 can regulate signaling pathways that related to proliferation, cell cycle, inflammation and oxidative stress in CAL-27 cell.

Gene expression profiling of common signal transduction pathways affected by rBMSCs/F92A-Cav1 in the lungs of rat with pulmonary arterial hypertension

BACKGROUND

Pulmonary arterial hypertension (PAH) is associated with sustained vasoconstriction, inflammation and suppressed apoptosis of smooth muscle cells. Our previous studies have found that rat bone marrow-derived mesenchymal stem cells (rBMSCs) transduced with a mutant caveolin-1(F92A-Cav1) could enhance endothelial nitric oxide synthase (eNOS) activity and improve pulmonary vascular remodeling, but the potential mechanism is not yet fully explored. The present study was to investigate the gene expression profile upon rBMSCs/F92A-Cav1delivered to PAH rat to evaluate the role of F92A-Cav1 in its regulation.

METHODS

PAH was induced with monocrotaline (MCT, 60mg/kg) prior to delivery of lentiviral vector transduced rBMSCs expressing Cav1 or F92A-Cav1. Gene expression profiling was performed using Rat Signal Transduction PathwayFinder array. The expression changes of 84 key genes representing 10 signal transduction pathways in rat following rBMSCs/F92A-Cav1 treatment was examined.

RESULTS

Screening with the Rat Signal Transduction PathwayFinder R² PCR Array system and subsequent western blot, immunohistochemistry or real time PCR analysis revealed that F92A-Cav1 modified rBMSCs can inhibit the inflammation factors (TNF-alpha, Icam1 and C/EBPdelta), pro-proliferation genes (c-Myc, Bcl2a1d, Notch1and Hey2), oxidative stress gene (Hmox1) and activate cell cycle arrested gene Cdkn1a, ameliorating inflammation and inhibiting cell proliferation in PAH rat.

CONCLUSION

rBMSCs/F92A-Cav1 inhibits inflammation and cell proliferation by regulating signaling pathways that related to inflammation, proliferation, cell cycle and oxidative stress.