scholarly journals Polysaccharides from the Edible Mushroom Agaricus bitorquis (Quél.) Sacc. Chaidam Show Anti-hypoxia Activities in Pulmonary Artery Smooth Muscle Cells

2019 ◽  
Vol 20 (3) ◽  
pp. 637 ◽  
Author(s):  
Yingchun Jiao ◽  
Hui Kuang ◽  
Jianan Wu ◽  
Qihe Chen

Three kinds of new water-soluble polysaccharides (FA, FB and FC) were isolated from wild mushroom Agaricus bitorquis (Quél.) Sacc. Chaidam by the classical method “water extraction and alcohol precipitation” and purified by column chromatography. The Mw of FA, FB and FC ranged from 5690 Da to 38,340 Da. The three polysaccharide fractions in the fruiting body were mainly composed of 4 kinds of monosaccharides, including glucose, galactose, mannose, and arabinose, among which glucose and galactose were the major monosaccharides. The FTIR and NMR spectroscopy indicated that the skeleton of three fractions composed of a (1→4)-α-D-glycosidic backbone containing α-D-mannopyranose. In vitro anti-hypoxia activity data showed that three polysaccharide fractions possessed a significant effect on inhibiting PASM cells apoptosis under hypoxia. Among them, FC at the concentration of 200 µg/mL revealed a significant anti-hypoxia effect. These results revealed that the intracellular polysaccharides possessed potent anti-hypoxic activity, which might be related to inhibiting LDH and NADPH oxidase expression and promoting the formation of 5-hydroxytryptamine, dopamine, endothelins, acetylcholine. More importantly, FC showed good performance inducing KV1.5 expression and prohibiting KIR6.2 formation at protein level.

2019 ◽  
Vol 17 (1) ◽  
Author(s):  
Fernando de la Cuesta ◽  
Ilaria Passalacqua ◽  
Julie Rodor ◽  
Raghu Bhushan ◽  
Laura Denby ◽  
...  

Abstract Background Excessive TGF-β signalling has been shown to underlie pulmonary hypertension (PAH). Human pulmonary artery smooth muscle cells (HPASMCs) can release extracellular vesicles (EVs) but their contents and significance have not yet been studied. Here, we aimed to analyse the contents and biological relevance of HPASMC-EVs and their transport to human pulmonary arterial endothelial cells (HPAECs), as well as the potential alteration of these under pathological conditions. Methods We used low-input RNA-Seq to analyse the RNA cargoes sorted into released HPASMC-EVs under basal conditions. We additionally analysed the effects of excessive TGF-β signalling, using TGF-β1 and BMP4, in the transcriptome of HPASMCs and their EVs. We then, for the first time, optimised Cre-loxP technology for its use with primary cells in vitro, directly visualising HPASMC-to-HPAEC communication and protein markers on cells taking up EVs. Furthermore we could analyse alteration of this transport with excessive TGF-β signalling, as well as by other cytokines involved in PAH: IL-1β, TNF-α and VEGFA. Results We were able to detect transcripts from 2417 genes in HPASMC-EVs. Surprisingly, among the 759 enriched in HPASMC-EVs compared to their donor cells, we found Zeb1 and 2 TGF-β superfamily ligands, GDF11 and TGF-β3. Moreover, we identified 90 genes differentially expressed in EVs from cells treated with TGF-β1 compared to EVs in basal conditions, including a subset involved in actin and ECM remodelling, among which were bHLHE40 and palladin. Finally, using Cre-loxP technology we showed cell-to-cell transfer and translation of HPASMC-EV Cre mRNA from HPASMC to HPAECs, effectively evidencing communication via EVs. Furthermore, we found increased number of smooth-muscle actin positive cells on HPAECs that took up HPASMC-EVs. The uptake and translation of mRNA was also higher in activated HPAECs, when stimulated with TGF-β1 or IL-1β. Conclusions HPASMC-EVs are enriched in RNA transcripts that encode genes that could contribute to vascular remodelling and EndoMT during development and PAH, and TGF-β1 up-regulates some that could enhance this effects. These EVs are functionally transported, increasingly taken up by activated HPAECs and contribute to EndoMT, suggesting a potential effect of HPASMC-EVs in TGF-β signalling and other related processes during PAH development.


2003 ◽  
Vol 81 (7) ◽  
pp. 711-719 ◽  
Author(s):  
Eric Dubuis ◽  
Mathieu Gautier ◽  
Alexandre Melin ◽  
Manuel Rebocho ◽  
Catherine Girardin ◽  
...  

Exogenous carbon monoxide (CO) induces pulmonary vasodilation by acting directly on pulmonary artery (PA) smooth muscle cells. We investigated the contribution of K+ channels and soluble guanylyl cyclase to the regulation of PA tone by acute CO in chronic hypoxic rats (3 weeks at 0.5 atm (1 atm = 101.325 kPa); hypoxic) and in chronic hypoxic rats exposed to exogenous CO (3 weeks at 0.5 atm + 50 ppm CO; hypoxic-CO). Acute CO induced relaxation in PA rings from all animals. However, the amplitude of CO relaxation was significantly decreased in hypoxic rings and increased in hypoxic-CO rings. This different effect occurred with a decrease and an increase of pD2, respectively, in hypoxic and hypoxic-CO rings. We showed a positive relation between the percentage of inhibition of CO relaxation by a blocker of K+ channels and the increase of CO sensitivity. Thus, we showed for the first time that chronic hypoxia decreases acute CO sensitivity, which in contrast, increases in the presence of chronic CO. The present study provides initial evidence of a link between increased K+-channel activity and CO sensitivity.Key words: K+-channel blocker, tetraethylammonium, soluble guanylyl cyclase, gasotransmitter.


Toxicology ◽  
2017 ◽  
Vol 375 ◽  
pp. 37-47 ◽  
Author(s):  
Virginie Dubes ◽  
Thibaud Parpaite ◽  
Thomas Ducret ◽  
Jean-François Quignard ◽  
Stéphane Mornet ◽  
...  

2016 ◽  
Vol 311 (4) ◽  
pp. H944-H957 ◽  
Author(s):  
Jason Boehme ◽  
Xutong Sun ◽  
Kathryn V. Tormos ◽  
Wenhui Gong ◽  
Manuela Kellner ◽  
...  

Vascular cell hyperproliferation and metabolic reprogramming contribute to the pathophysiology of pulmonary arterial hypertension (PAH). An important cause of PAH in children with congenital heart disease (CHD) is increased pulmonary blood flow (PBF). To better characterize this disease course we studied early changes in pulmonary artery smooth muscle cell (PASMC) proliferation and metabolism using a unique ovine model of pulmonary overcirculation. Consistent with PAH in adults, PASMCs derived from 4-wk-old lambs exposed to increased PBF (shunt) exhibited increased rates of proliferation. While shunt PASMCs also exhibited significant decreases in mitochondrial oxygen consumption, membrane potential, and tricarboxylic acid (TCA) cycle function, suggesting a switch to Warburg metabolism as observed in advanced PAH in adults, they unexpectedly demonstrated decreased glycolytic lactate production, likely due to enhanced flux through the pentose phosphate pathway (PPP). This may be a response to the marked increase in NADPH oxidase (Nox) activity and decreased NADPH/NADP+ ratios observed in shunt PASMCs. Consistent with these findings, pharmacological inhibition of Nox activity preferentially slowed the growth of shunt PASMCs in vitro. Our results therefore indicate that PASMC hyperproliferation is observed early in the setting of pulmonary overcirculation and is accompanied by a unique metabolic profile that is independent of HIF-1α, PDHK1, or increased glycolytic flux. Our results also suggest that Nox inhibition may help prevent pulmonary overcirculation-induced PAH in children born with CHD.


2012 ◽  
Vol 303 (8) ◽  
pp. L682-L691 ◽  
Author(s):  
Deming Gou ◽  
Ramaswamy Ramchandran ◽  
Xiao Peng ◽  
Lijun Yao ◽  
Kang Kang ◽  
...  

MicroRNAs (miRNAs) were recently reported to play an important role in the pathogenesis of pulmonary arterial hypertension (PAH), but it is not clear which miRNAs are important or what pathways are involved in the process. Because hypoxia is an important stimulus for human pulmonary artery smooth muscle cell (HPASMC) proliferation and PAH, we performed miRNA microarray assays in hypoxia-treated and control HPASMC. We found that miR-210 is the predominant miRNA induced by hypoxia in HPASMC. Induction of miR-210 was also observed in whole lungs of mice with chronic hypoxia-induced PAH. We found that transcriptional induction of miR-210 in HPASMC is hypoxia-inducible factor-1α dependent. Inhibition of miR-210 in HPASMC caused a significant decrease in cell number due to increased apoptosis. We found that miR-210 appears to mediate its antiapoptotic effects via the regulation of transcription factor E2F3, a direct target of miR-210. Our results have identified miR-210 as a hypoxia-inducible miRNA both in vitro and in vivo, which inhibits pulmonary vascular smooth muscle cell apoptosis in hypoxia by specifically repressing E2F3 expression.


2021 ◽  
Vol 12 ◽  
Author(s):  
Yali Wang ◽  
Xiaoming Tan ◽  
Yunjiang Wu ◽  
Sipei Cao ◽  
Yueyan Lou ◽  
...  

Currently, new strategies for the diagnosis and treatment of hypoxia-induced pulmonary hypertension (HPH) are urgently required. The unique features of circRNAs have unveiled a novel perspective for understanding the biological mechanisms underlying HPH and the possibility for innovative strategies for treatment of HPH. CircRNAs function as competing endogenous RNAs (CeRNA) to sequester miRNAs and regulate the expression of target genes. This study aimed to explore the roles of hsa_circ_0002062 on the biological behaviors of pulmonary artery smooth muscle cells (PASMCs) in hypoxic conditions. A number of in vitro assays, such as RNA-binding protein immunoprecipitation (RIP), RNA pull-down, and dual-luciferase assays were performed to evaluate the interrelationship between hsa_circ_0002062, hsa-miR-942-5P, and CDK6. The potential physiological functions of hsa_circ_0002062, hsa-miR-942-5P, and CDK6 in hypoxic PASMCs were investigated through expression modulation. Our experiments demonstrated that hsa_circ_0002062 functions as a ceRNA, acts as a sponge for hsa-miR-942-5P, and consequently activates CDK6, which further promotes pulmonary vascular remodeling. Therefore, we speculate that hsa_circ_0002062 could serve as a candidate diagnostic biomarker and potential therapeutic target for HPH.


Sign in / Sign up

Export Citation Format

Share Document