Modulation and roles of the endothelins in the pathophysiology of pulmonary embolism

2003 ◽  
Vol 81 (6) ◽  
pp. 555-569 ◽  
Author(s):  
Bruno Battistini

Recent research on the endothelins (ETs) and their pathways in acute pulmonary embolism (APE) has led to significant advances in the understanding of this disease. ETs are potent vasoconstrictors and bronchoconstrictors found abundantly in the lung and can be released by stimuli such as endothelial injury, hypoxia, or thrombin, a key product in the coagulation cascade. Many studies using different approaches and methods of inducing pulmonary embolization, both in vitro and in vivo in various species, have mostly shown that ETs play an important role in the pathophysiology of APE. These results were obtained by comparing the hemodynamic data in the presence or absence of various ETs inhibitors, but also by assessing the modulation of the ET-related elements of this system by molecular, cell biology, and pharmacological methods. Based on the current understanding, a mechanism involving the ET pathway in the pathophysiology of APE is proposed for the reader's considerations. We postulate that ETs are primary mediators in APE based on the following: (i) their source from pulmonary endothelial cells where the primary injury takes place; (ii) their direct vasconstrictive, bronchoconstrictive, and promitogenic effects via distinct ET receptors; and (iii) their indirect effects associated with the secondary release of thromboxane and other mediators, which are released from inflammatory cells and platelets, which together can potentiate the overall hemodynamic response, most specifically the pulmonary vascular bed. Such combined effects of ETs on bronchomotor and vasomotor tone in the lung can adversely affect ventilation perfusion matching and lead to severe hypoxemia without causing significant changes in the chest X-ray of these patients. Thus, we may consider ET inhibitors as future current therapeutic agents in patients with PE.Key words: pulmonary embolism, thrombus, air, pulmonary hypertension, blood gas, hypoxia, endothelin, endothelin receptor, antagonists.

2020 ◽  
Author(s):  
Hongyu Mao ◽  
Lina Liu ◽  
Yamin Hu

Abstract Background Pulmonary embolism (PE) is a primary clinical manifestation of venous thromboembolism (VTE). It has been demonstrated that pulmonary endothelial cells (PECs) are apoptotic-resistance in PE. In this study, PECs were collected from PE patients and mouse models. Western blot, RT-PCR, flow cytometry, H&E and TUNEL assay, confocal and TEM microscopy, and luciferase reporter assay were performed to determine the effects of miR-28-3p on PECs apoptosis and if exosomes can act as the shuttle to transport miR-28-3p to PECs. Material and Methods The results revealed that apoptosis and miR-28-3p were downregulated in PECs of PE. The miR-28-3p mimics and inhibitor enhanced and further inhibited apoptosis in PECs, respectively. Results Both miR-28-3p-modified adipose tissue-derived mesenchymal stem cells (AMSCs) and AMSC-derived exosomes upregulated miR-28-3p expression in PECs, leading to elevated apoptosis of PECs. Apoptosis inhibitor 5 (API5) was a direct target gene of miR-28-3p, and the overexpression of API5 in miR-28-3p-modified PECs further suppressed apoptosis. Conclusions Furthermore, the administration of miR-28-3p-modified exosomes to PE mouse model promoted apoptosis in PECs. In conclusion, exosomal miR-28-3p could ameliorate PE-associated apoptosis-resistance in PECs through targeting API5 in vitro and in vivo. Therefore, AMSCs-derived exosome is a promising way to deliver functioning miRNA to PECs, providing insight into novel therapy of PE.


2020 ◽  
Vol 18 ◽  
Author(s):  
Zirui Zhang ◽  
Shangcong Han ◽  
Panpan Liu ◽  
Xu Yang ◽  
Jing Han ◽  
...  

Background: Chronic inflammation and lack of angiogenesis are the important pathological mechanisms in deep tissue injury (DTI). Curcumin is a well-known anti-inflammatory and antioxidant agent. However, curcumin is unstable under acidic and alkaline conditions, and can be rapidly metabolized and excreted in the bile, which shortens its bioactivity and efficacy. Objective: This study aimed to prepare curcumin-loaded poly (lactic-co-glycolic acid) nanoparticles (CPNPs) and to elucidate the protective effects and underlying mechanisms of wound healing in DTI models. Methods: CPNPs were evaluated for particle size, biocompatibility, in vitro drug release and their effect on in vivo wound healing. Results : The results of in vivo wound closure analysis revealed that CPNP treatments significantly improved wound contraction rates (p<0.01) at a faster rate than other three treatment groups. H&E staining revealed that CPNP treatments resulted in complete epithelialization and thick granulation tissue formation, whereas control groups resulted in a lack of compact epithelialization and persistence of inflammatory cells within the wound sites. Quantitative real-time PCR analysis showed that treatment with CPNPs suppressed IL-6 and TNF-α mRNA expression, and up-regulated TGF-β, VEGF-A and IL-10 mRNA expression. Western blot analysis showed up-regulated protein expression of TGF-β, VEGF-A and phosphorylatedSTAT3. Conclusion: Our results showed that CPNPs enhanced wound healing in DTI models, through modulation of the JAK2/STAT3 signalling pathway and subsequent upregulation of pro-healing factors.


Parasitology ◽  
2006 ◽  
Vol 133 (3) ◽  
pp. 261-278 ◽  
Author(s):  
A. HEMPHILL ◽  
N. VONLAUFEN ◽  
A. NAGULESWARAN

Neospora caninumis an apicomplexan parasite that is closely related toToxoplasma gondii, the causative agent of toxoplasmosis in humans and domestic animals. However, in contrast toT. gondii, N. caninumrepresents a major cause of abortion in cattle, pointing towards distinct differences in the biology of these two species. There are 3 distinct key features that represent potential targets for prevention of infection or intervention against disease caused byN. caninum. Firstly, tachyzoites are capable of infecting a large variety of host cellsin vitroandin vivo. Secondly, the parasite exploits its ability to respond to alterations in living conditions by converting into another stage (tachyzoite-to-bradyzoite orvice versa). Thirdly, by analogy withT. gondii, this parasite has evolved mechanisms that modulate its host cells according to its own requirements, and these must, especially in the case of the bradyzoite stage, involve mechanisms that ensure long-term survival of not only the parasite but also of the host cell. In order to elucidate the molecular and cellular bases of these important features ofN. caninum, cell culture-based approaches and laboratory animal models are being exploited. In this review, we will summarize the current achievements related to host cell and parasite cell biology, and will discuss potential applications for prevention of infection and/or disease by reviewing corresponding work performed in murine laboratory infection models and in cattle.


Blood ◽  
2012 ◽  
Vol 119 (11) ◽  
pp. 2443-2451 ◽  
Author(s):  
Tatiana Akimova ◽  
Ulf H. Beier ◽  
Yujie Liu ◽  
Liqing Wang ◽  
Wayne W. Hancock

Abstract Clinical and experimental studies show that inhibition of histone/protein deacetylases (HDAC) can have important anti-neoplastic effects through cytotoxic and proapoptotic mechanisms. There are also increasing data from nononcologic settings that HDAC inhibitors (HDACi) can exhibit useful anti-inflammatory effects in vitro and in vivo, unrelated to cytotoxicity or apoptosis. These effects can be cell-, tissue-, or context-dependent and can involve modulation of specific inflammatory signaling pathways as well as epigenetic mechanisms. We review recent advances in the understanding of how HDACi alter immune and inflammatory processes, with a particular focus on the effects of HDACi on T-cell biology, including the activation and functions of conventional T cells and the unique T-cell subset, composed of Foxp3+ T-regulatory cells. Although studies are still needed to tease out details of the various biologic roles of individual HDAC isoforms and their corresponding selective inhibitors, the anti-inflammatory effects of HDACi are already promising and may lead to new therapeutic avenues in transplantation and autoimmune diseases.


Pharmaceutics ◽  
2018 ◽  
Vol 10 (4) ◽  
pp. 227 ◽  
Author(s):  
Bayan Darwesh ◽  
Hibah Aldawsari ◽  
Shaimaa Badr-Eldin

(1) Background: Fluconazole, used orally for vaginal candidiasis, has reported gastrointestinal side effects. Therefore, researchers directed towards the drug vaginal delivery. However, vaginal delivery is limited by poor retention and leakage. Thus, this work aimed at exploring chitosan/anion polyelectrolyte complex (PEC) for the formulation of fluconazole vaginal inserts with controlled release and appreciable mucoadhesion. (2) Methods: PECs were prepared and assessed for interactions. Fluconazole PEC based vaginal inserts were prepared by lyophilization using mannitol. 3151 factorial design was applied to investigate the effect of the anion type and Chitosan/anion ratio on the inserts mucoadhesion and release properties. The optimized insert [based on 5:5 chitosan: anionic polymer (sodium alginate)] release was modulated by the release retardant; Compritol® 888. The selected formulation was subjected to microbiological and histological evaluation. (3) Results: Fluconazole inserts showed satisfactory drug content, acceptable friability percentages and highest swelling indices at six hours. Statistical analysis showed significant effect of the studied factors on detachment force and release properties. Microbiological assays revealed significantly higher antifungal activity of inserts compared to fluconazole solution. Reduced inflammatory cells were confirmed by histological evaluation. (4) Conclusion: CH/Alg based vaginal insert could be a promising platform for vaginal delivery of antifungal drugs used for vaginal candidiasis treatment.


2020 ◽  
Vol 295 (30) ◽  
pp. 10293-10306 ◽  
Author(s):  
Qiquan Wang ◽  
Xianling Bian ◽  
Lin Zeng ◽  
Fei Pan ◽  
Lingzhen Liu ◽  
...  

Endolysosomes are key players in cell physiology, including molecular exchange, immunity, and environmental adaptation. They are the molecular targets of some pore-forming aerolysin-like proteins (ALPs) that are widely distributed in animals and plants and are functionally related to bacterial toxin aerolysins. βγ-CAT is a complex of an ALP (BmALP1) and a trefoil factor (BmTFF3) in the firebelly toad (Bombina maxima). It is the first example of a secreted endogenous pore-forming protein that modulates the biochemical properties of endolysosomes by inducing pore formation in these intracellular vesicles. Here, using a large array of biochemical and cell biology methods, we report the identification of BmALP3, a paralog of BmALP1 that lacks membrane pore-forming capacity. We noted that both BmALP3 and BmALP1 contain a conserved cysteine in their C-terminal regions. BmALP3 was readily oxidized to a disulfide bond-linked homodimer, and this homodimer then oxidized BmALP1 via disulfide bond exchange, resulting in the dissociation of βγ-CAT subunits and the elimination of biological activity. Consistent with its behavior in vitro, BmALP3 sensed environmental oxygen tension in vivo, leading to modulation of βγ-CAT activity. Interestingly, we found that this C-terminal cysteine site is well conserved in numerous vertebrate ALPs. These findings uncover the existence of a regulatory ALP (BmALP3) that modulates the activity of an active ALP (BmALP1) in a redox-dependent manner, a property that differs from those of bacterial toxin aerolysins.


1994 ◽  
Vol 266 (6) ◽  
pp. L593-L611 ◽  
Author(s):  
M. D. Evans ◽  
W. A. Pryor

The proteinase-antiproteinase theory for the pathogenesis of emphysema proposes that the connective tissue destruction associated with emphysema arises from excessive proteinase activity in the lower respiratory tract. For this reason, the relative activities of neutrophil elastase and alpha 1-proteinase inhibitor (alpha 1-PI) are considered important. Most emphysema is observed in smokers; therefore, alpha 1-PI has been studied as a target for smoke-induced damage. Damage to alpha 1-PI in lung fluid could occur by several mechanisms involving species delivered to the lung by cigarette smoke and/or stimulated inflammatory cells. Oxidative damage to alpha 1-PI has received particular attention, since both cigarette smoke and inflammatory cells are rich sources of oxidants. In this article we review almost two decades of research on mechanistic studies of damage to alpha 1-PI by cigarette smoke and phagocytic cells in vitro, studies emphasizing the importance of elastinolytic activity in the pathogenesis of emphysema in vivo and studies of human lung lavage fluid to detect defects in alpha 1-PI at the molecular and functional levels.


1993 ◽  
Vol 121 (3) ◽  
pp. 513-519 ◽  
Author(s):  
W Jiang ◽  
J Lechner ◽  
J Carbon

We have cloned and determined the nucleotide sequence of the gene (CBF2) specifying the large (110 kD) subunit of the 240-kD multisubunit yeast centromere binding factor CBF3, which binds selectively in vitro to yeast centromere DNA and contains a minus end-directed microtubule motor activity. The deduced amino acid sequence of CBF2p shows no sequence homologies with known molecular motors, although a consensus nucleotide binding site is present. The CBF2 gene is essential for viability of yeast and is identical to NDC10, in which a conditional mutation leads to a defect in chromosome segregation (Goh, P.-Y., and J. V. Kilmartin, in this issue of The Journal of Cell Biology). The combined in vitro and in vivo evidence indicate that CBF2p is a key component of the budding yeast kinetochore.


2022 ◽  
Vol 12 ◽  
Author(s):  
Xiangbing Mao ◽  
Rui Sun ◽  
Qingxiang Wang ◽  
Daiwen Chen ◽  
Bing Yu ◽  
...  

Inflammatory bowel disease (namely, colitis) severely impairs human health. Isoleucine is reported to regulate immune function (such as the production of immunoreactive substances). The aim of this study was to investigate whether l-isoleucine administration might alleviate dextran sulfate sodium (DSS)-induced colitis in rats. In the in vitro trial, IEC-18 cells were treated by 4 mmol/L l-isoleucine for 12 h, which relieved the decrease of cell viability that was induced by TNF-α (10 ng/ml) challenge for 24 h (P &lt;0.05). Then, in the in vivo experiment, a total of 44 Wistar rats were allotted into 2 groups that were fed l-isoleucine-supplemented diet and control diet for 35 d. From 15 to 35 d, half of the rats in the 2 groups drank the 4% DSS-adding water. Average daily gain, average daily feed intake and feed conversion of rats were impaired by DSS challenge (P &lt;0.05). Drinking the DSS-supplementing water also increased disease activity index (DAI) and serum urea nitrogen level (P &lt;0.05), shortened colonic length (P &lt;0.05), impaired colonic enterocyte apoptosis, cell cycle, and the ZO-1 mRNA expression (P &lt;0.05), increased the ratio of CD11c-, CD64-, and CD169-positive cells in colon (P &lt;0.05), and induced extensive ulcer, infiltration of inflammatory cells, and collagenous fiber hyperplasia in colon. However, dietary l-isoleucine supplementation attenuated the negative effect of DSS challenge on growth performance (P &lt;0.05), DAI (P &lt;0.05), colonic length and enterocyte apoptosis (P &lt;0.05), and dysfunction of colonic histology, and downregulated the ratio of CD11c-, CD64-, and CD169-positive cells, pro-inflammation cytokines and the mRNA expression of TLR4, MyD88, and NF-κB in the colon of rats (P &lt;0.05). These results suggest that supplementing l-isoleucine in diet improved the DSS-induced growth stunting and colonic damage in rats, which could be associated with the downregulation of inflammation via regulating TLR4/MyD88/NF-κB pathway in colon.


2019 ◽  
Vol 39 (11) ◽  
Author(s):  
Hua Chen ◽  
Dongxia Liu ◽  
Lan Ge ◽  
Tao Wang ◽  
Zhenzhen Ma ◽  
...  

AbstractCatestatin (CTS), a catecholamine-release inhibitory peptide, exerts pleiotropic cardiac protective effects. Pulmonary embolism caused by deep vein thrombosis involving vascular dysfunction. The present study aims to investigate the effects of CTS on thrombus formation that may inhibit the development of pulmonary embolism and its potential pathway. Acute pulmonary embolism (APE) model was developed as an in vivo model. The effects of CTS on mice with APE were examined. Human pulmonary artery endothelial cells (HPAECs) were pretreated with CTS before thrombin stimulation, and endothelial inflammation and underlying mechanisms were evaluated in vitro. That plasma CTS level was decreased in APE mice, while the number of platelets was significantly increased. The decreased circulating CTS level negatively associated with the number of platelets. CTS administration increased the survival rate of APE mice and protected against microvascular thrombosis in lung. APE-induced the increase in platelets number and plasma von Willebrand factor (VWF) were inhibited by CTS. Platelets from CTS-treated APE mice showed impaired agonist-induced platelets aggregation and spreading. CTS also ameliorated APE-induced the systemic inflammatory response. In in vivo study, thrombin-induced the increase in inflammation, TLR-4 expression and p38 phosphorylation were abrogated by CTS in HPAECs. Furthermore, TLR-4 overexpression inhibited the effect of CTS on VWF release and inflammation in HPAECs. Collectively, CTS increases thrombus resolution by attenuating endothelial inflammation at partially via inhibiting TLR-4-p38 pathway. The present study may provide a novel approach for anti-thrombosis.


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