VEGF attenuates lung injury by inducing homing of CD133+ progenitors via VEGFR1

Expression of Angiopoietin-2 in Lung Tissue of Juvenile SD Rats with Lipopolysaccharide-Induced Acute Lung Injury and the Role of Ulinastatin

This study aimed to observe the expression of angiopoietin-2 (Ang-2) in the lung tissue of juvenile SD rats with lipopolysaccharide (LPS)-induced acute lung injury (ALI) and to clarify the role of ulinastatin (UTI). Ninety 18-21-day-old juvenile SD male rats were randomly divided into five groups (n = 18). ALI rat model was established by intraperitoneal injection of LPS (LPS 10 mg/kg), while the control group was given the same dose of normal saline. The UTI intervention group was given the injection of UTI (5000 U/mL) immediately after the injection of LPS, which was divided into UTI low-dose group (LPS + 5 ml/kg UTI), UTI medium-dose group (LPS + 10 ml/kg UTI), and UTI high-dose group (LPS + 20 ml/kg UTI).The respiratory status of each group of rats was observed, and six rats were randomly selected to be killed in each group at 6, 12, and 24 h, and the lung tissues were dissected and retained. The pathological changes of the lung tissues were observed by hematoxylin-eosin (HE) staining, the expression levels and locations of Ang-2 and vascular endothelial growth factor (VEGF) in lung tissue were observed by immunohistochemical staining, and the expressions of genes and proteins of Ang-2 and VEGF were detected by quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis. Three hours after intraperitoneal injection, rats in the model group developed shortness of breath and the developed respiratory distress progressed over time. The lung pathological changes in the model group were obvious compared with those in the control group, and gradually worsened with time, and the pathological changes of lung in the rats in the UTI intervention group were reduced compared with those in the model group. At different time points, the expressions of Ang-2 and VEGF in the lung tissue of rats in the model group were higher than those in the control group, and were lower in the UTI intervention group than those in the model group. The expressions of Ang-2 and VEGF protein were lower in the low-dose group of UTI group than those in the high-dose group of UTI group at different time points (P < 0.05), and the expressions of Ang-2 and VEGF protein in the low-dose group of UTI were significantly lower than those in the medium-dose group at 12 h and 24 h (P < 0.05). The expression of Ang-2 was increased in the lung tissue of juvenile SD rats with LPS-induced ALI, and was associated with the degree of lung injury. UTI might attenuate LPS-induced ALI by inhibiting the expression of Ang-2 in lung tissue, and the low dose was more obvious than the medium and high dose.

Biomimetic scaffold-based stem cell transplantation promotes lung regeneration

Therapeutic options are limited for severe lung injury and disease as the spontaneous regeneration of functional alveolar is terminated owing to the weakness of the inherent stem cells and the dyscrasia of the niche. Umbilical cord mesenchymal-derived stem cells (UC-MSCs) have been applied to clinical trials to promote lung repair through stem cell niche restruction. However, the application of UC-MSCs is hampered by the effectiveness of cell transplantation with few cells homing to the injury sites and poor retention, survival, and proliferation in vivo. In this study, we constructed an artificial three-dimensional (3D) biomimetic scaffold-based MSCs implant to establish a beneficial regeneration niche for endogenous stem cells in situ lung regeneration. The therapeutic potential of 3D biomimetic scaffold-based MSCs implants was evaluated by 3D culture in vitro. And RNA sequencing (RNA-Seq) was mapped to explore the gene expression involved in the niche improvement. Next, a model of partial lung resection was established in rats, and the implants were implanted into the operative region. Effects of the implants on rat resected lung injury repair were detected. The results revealed that UC-MSCs loaded on biomimetic scaffolds exerted strong paracrine effects and some UC-MSCs migrated to the lung from scaffolds and had long-term retention to suppress inflammation and fibrosis in residual lungs and promoted vascular endothelial cells and alveolar type II epithelial cells to enter the scaffolds. Then, under the guidance of the ECM-mimicking structures of scaffolds and the stimulation of the remaining UC-MSCs, vascular and alveolar-like structures were formed in the scaffold region. Moreover, the general morphology of the operative lung was also restored. Taken together, the artificial 3D biomimetic scaffold-based MSCs implants induce in situ lung regeneration and recovery after lung destruction, providing a promising direction for tissue engineering and stem cell strategies in lung regeneration.

Effects of plasma acid on rat uterine tissue <i>in vitro</i>

The aim of the study was to evaluate the effect of plasma acid on the uterine tissue of laboratory animals in vitro.

Materials and methods. Treatment of dimethyl sulfoxide – water solution and water for injections with a spark discharge in air resulted in a decrease in pH, which contributed to generation of plasma acid in the solutions. We incubated uterine tissues in vitro in plasma acid at room temperature for 30 minutes. The treated tissues were examined histologically and immunohistochemically.

Results. We showed that plasma acid had pronounced biological activity. Immunohistochemistry was used to show that, depending on the type of a solution, plasma acid altered generation of nitrosative damage products (3-NT) and oxidative DNA damage (8-OHdG) and modulated the number of cells with high proliferative potential (including CD133+ cells) and production of vascular endothelial growth factor (VEGF). These effects contributed to the general cytotoxicity of plasma acid solutions.

Conclusion. During 30-minute exposure in vitro, plasma acid prepared from the dimethyl sulfoxide (DMSO) – water mixture exhibits various biological effects in uterine tissue samples obtained from experimental animals. Plasma-treated water exerts cytotoxic effects associated with oxidative DNA damage and promotes induction of pro-angiogenic activity in the uterine tissue. Plasma-treated DMSO does not have a cytotoxic effect. It inhibits cell proliferation, reducing the population of CD133+ cells and VEGF production in the tissue.

Mechanism of Compound Houttuynia Mixture as an Anti-COVID-19 Drug Based on Network Pharmacology and Molecular Docking

Objective

To explore the anti-COVID-19 active components and mechanism of Compound Houttuynia mixture by using network pharmacology and molecular docking.

Methods

First, the main chemical components of Compound Houttuynia mixture were obtained by using the TCMSP database and referring to relevant chemical composition literature. The components were screened for OB ≥30% and DL ≥0.18 as the threshold values. Then Swiss Target Prediction database was used to predict the target of the active components and map the targets of COVID-19 obtained through GeneCards database to obtain the gene pool of the potential target of COVID-19 resistance of the active components of Compound Houttuynia mixture. Next, DAVID database was used for GO enrichment and KEGG pathway annotation of targets function. Cytoscape 3.8.0 software was used to construct a “components-targets-pathways” network. Then String database was used to construct a “protein-protein interaction” network. Finally, the core targets, SARS-COV-2 3 Cl, ACE2 and the core active components of Compound Houttuyna Mixture were imported into the Discovery Studio 2016 Client database for molecular docking verification.

Results

Eighty-two active compounds, including Xylostosidine, Arctiin, ZINC12153652 and ZINC338038, were screened from Compound Houttuyniae mixture. The key targets involved 128 targets, including MAPK1, MAPK3, MAPK8, MAPK14, TP53, TNF, and IL6. The HIF-1 signaling, VEGF signaling, TNF signaling and another 127 signaling pathways associated with COVID-19 were affected ( P < 0.05). From the results of molecular docking, the binding ability between the selected active components and the core targets was strong.

Conclusion

Through the combination of network pharmacology and molecular docking technology, this study revealed that the therapeutic effect of Compound Houttuynia mixture on COVID-19 was realized through multiple components, multiple targets and multiple pathways, which provided a certain scientific basis of the clinical application of Compound Houttuynia mixture.

Premobilization of CD133+ progenitors is associated with attenuated inflammation-induced pulmonary dysfunction following extracorporeal circulation in mice

OBJECTIVES

Progenitor cells mobilized by granulocyte colony-stimulating factor (G-CSF) have been shown to lessen acute kidney injury induced by extracorporeal circulation (ECC). Both acute kidney injury and lung injury are characterized by endothelial dysfunction. Our goal was to examine whether and how G-CSF-mobilized progenitors with endothelial capacity may help mitigate ECC-induced pulmonary dysfunction.

METHODS

G-CSF (10 μg/kg/day) was administered subcutaneously to C57BL/6 mice before or at the initiation of the ECC process, after which lung injury was assessed by measuring neutrophils in the fluid from bronchoalveolar lavage and determining the pathological score in lung tissue. CD133+ progenitors were isolated and injected into C57BL/6 mice before ECC in vivo. We incubated the CD133+ cells with pulmonary monocytes or neutrophils isolated from naïve mice in vitro.

RESULTS

Pretreatment with G-CSF for 2 days significantly decreased the number of neutrophils in the bronchoalveolar lavage fluid, and the pathological score (P < 0.01; n = 5) improved the PaO2/FiO2 ratio [193.4 ± 12.7 (ECC without G-CSF) vs 305.6 ± 22.6 mmHg (ECC with G-CSF); P = 0.03, n = 5] and suppressed neutrophil elastase and tumour necrosis factor-α levels in the circulation; we also observed increases in both circulating and pulmonary populations of CD133+ progenitors. Similar effects were observed in animals pretreated with CD133+ progenitors instead of G-CSF before ECC. The majority of CD133+/CD45- and CD133+/CD45+ progenitors were mobilized in the lung and in the circulation, respectively. Incubating CD133+ progenitors with neutrophils or pulmonary monocytes blocked lipopolysaccharide-induced release of inflammatory factors.

CONCLUSIONS

Our results suggest that pretreatment of G-CSF attenuates ECC-induced pulmonary dysfunction through inhibiting the inflammatory response in lung tissue and in the circulation with associated premobilization of CD133+ progenitors.

A stepwise integrated multi-system to screen quality markers of Chinese classic prescription Qingzao Jiufei decoction on the treatment of acute lung injury by combining 'network pharmacology-metabolomics-PK/PD modeling'

BACKGROUND

Previously, we have investigated the therapeutic mechanism of Qingzao Jiufei Decoction (QZJFD), a Chinese classic prescription, on acute lung injury (ALI), however, which remained to be further clarified together with the underlying efficacy related compounds for quality markers (Q-markers).

HYPOTHESIS/PURPOSE

To explore Q-markers of QZJFD on ALI by integrating a stepwise multi-system with 'network pharmacology-metabolomics- pharmacokinetic (PK)/ pharmacodynamic (PD) modeling'.

METHODS

First, based on in vitro and in vivo component analysis, a network pharmacology strategy was developed to identify active components and potential action mechanism of QZJFD on ALI. Next, studies of poly-pharmacology and non-targeted metabolomics were used to elaborate efficacy and verify network pharmacology results. Then, a comparative PK study on active components in network pharmacology was developed to profile their dynamic laws in vivo under ALI, suggesting Q-marker candidates. Next, quantified analytes with marked PK variations after modeling were fitted with characteristic endogenous metabolites along drug concentration-efficacy-time curve in a PK-PD modeling to verify and select primary effective compounds. Finally, Q-markers were further chosen based on representativeness among analytes through validity analysis of PK quantitation of primary effective compounds.

RESULTS

In virtue of 121 and 33 compounds identified in vitro and in vivo, respectively, 33 absorbed prototype compounds were selected to construct a ternary network of '20 components-47 targets-113 pathways' related to anti-ALI of QZJFD. Predicted mechanism (leukocytes infiltration, cytokines, endogenous metabolism) were successively verified by poly-pharmacology and metabolomics. Next, 18 measurable components were retained from 20 analytes by PK comparison under ALI. Then, 15 primary effective compounds from 18 PK markers were further selected by PK-PD analysis. Finally, 9 representative Q-markers from 15 primary effective compounds attributed to principal (chlorogenic acid), ministerial (methylophiopogonanone A, methylophiopogonanone B), adjuvant (sesamin, ursolic acid, amygdalin), conductant drugs (liquiritin apioside, liquiritigenin and isoliquiritin) in QZJFD, were recognized by substitutability and relevance of plasmatic concentration at various time points.

CONCLUSION

9 Q-markers for QZJFD on ALI were identified by a stepwise integration strategy, moreover, which was a powerful tool for screening Q-makers involved with the therapeutic action of traditional Chinese medicine (TCM) prescription and promoting the process of TCM modernization and scientification.

Genetic variants of VEGFR-1 gene promoter in acute myocardial infarction

BACKGROUND

Coronary artery disease (CAD) including acute myocardial infarction (AMI) is a common complex disease caused by atherosclerosis. Vascular epithelial growth factor receptor-1 (VEGFR-1) stimulates angiogenesis and vascular permeability, and functions as a decoy to sequester VEGF and prevent initiation of intracellular signaling. VEGFR-1 knockout mice exhibit significantly higher mortality due to heart failure, cardiac hypertrophy, and cardiac dysfunction. An evident increase in macrophage infiltration and cardiac fibrosis are also observed after transverse aortic constriction. Therefore, VEGFR-1 gene variants may be involved in CAD. In this study, VEGFR-1 gene promoter was genetically and functionally analyzed in large cohorts of AMI patients and ethnic-matched controls.

RESULTS

A total of 16 DNA sequence variants (DSVs) including six single-nucleotide polymorphisms (SNPs) were found in the VEGFR-1 gene promoter and 5'-untranslated region. Five novel DSVs and one SNP were only identified in AMI patients group. These DSVs and SNP significantly altered the transcriptional activity of the VEGFR-1 gene promoter in both HEK-293 and H9c2 cells (P < 0.05). Further electrophoretic mobility shift assay indicated that the DSVs and SNPs evidently affected the binding of transcription factors.

CONCLUSIONS

The genetic variants in VEGFR-1 gene identified in AMI patients may alter the transcriptional activity of the VEGFR-1 gene promoter and change VEGFR-1 level, contributing to AMI development.