scholarly journals Absence of TNF-α enhances inflammatory response in the newborn lung undergoing mechanical ventilation

2016 ◽  
Vol 310 (10) ◽  
pp. L909-L918 ◽  
Author(s):  
Harald Ehrhardt ◽  
Tina Pritzke ◽  
Prajakta Oak ◽  
Melina Kossert ◽  
Luisa Biebach ◽  
...  

Bronchopulmonary dysplasia (BPD), characterized by impaired alveolarization and vascularization in association with lung inflammation and apoptosis, often occurs after mechanical ventilation with oxygen-rich gas (MV-O2). As heightened expression of the proinflammatory cytokine TNF-α has been described in infants with BPD, we hypothesized that absence of TNF-α would reduce pulmonary inflammation, and attenuate structural changes in newborn mice undergoing MV-O2. Neonatal TNF-α null (TNF-α−/−) and wild type (TNF-α+/+) mice received MV-O2 for 8 h; controls spontaneously breathed 40% O2. Histologic, mRNA, and protein analysis in vivo were complemented by in vitro studies subjecting primary pulmonary myofibroblasts to mechanical stretch. Finally, TNF-α level in tracheal aspirates from preterm infants were determined by ELISA. Although MV-O2 induced larger and fewer alveoli in both, TNF-α−/− and TNF-α+/+ mice, it caused enhanced lung apoptosis (TUNEL, caspase-3/-6/-8), infiltration of macrophages and neutrophils, and proinflammatory mediator expression (IL-1β, CXCL-1, MCP-1) in TNF-α−/− mice. These differences were associated with increased pulmonary transforming growth factor-β (TGF-β) signaling, decreased TGF-β inhibitor SMAD-7 expression, and reduced pulmonary NF-κB activity in ventilated TNF-α−/− mice. Preterm infants who went on to develop BPD showed significantly lower TNF-α levels at birth. Our results suggest a critical balance between TNF-α and TGF-β signaling in the developing lung, and underscore the critical importance of these key pathways in the pathogenesis of BPD. Future treatment strategies need to weigh the potential benefits of inhibiting pathologic cytokine expression against the potential of altering key developmental pathways.

Molecules ◽  
2019 ◽  
Vol 24 (15) ◽  
pp. 2729 ◽  
Author(s):  
Melo ◽  
Luzo ◽  
Lana ◽  
Santana

Leukocyte and platelet-rich plasma (L-PRP) is an autologous product that when activated forms fibrin nanofibers, which are useful in regenerative medicine. As an important part of the preparation of L-PRP, the centrifugation parameters may affect the release of soluble factors that modulate the behavior of the cells in the nanofibers. In this study, we evaluated the influences of four different centrifugation conditions on the concentration of platelets and leukocytes in L-PRP and on the anabolic/catabolic balance of the nanofiber microenvironment. Human adipose-derived mesenchymal stem cells (h-AdMSCs) were seeded in the nanofibers, and their viability and growth were evaluated. L-PRPs prepared at 100× g and 100 + 400× g released higher levels of transforming growth factor (TGF)-β1 and platelet-derived growth factor (PDGF)-BB due to the increased platelet concentration, while inflammatory cytokines interleukin (IL)-8 and tumor necrosis factor (TNF)-α were more significantly released from L-PRPs prepared via two centrifugation steps (100 + 400× g and 800 + 400× g) due to the increased concentration of leukocytes. Our results showed that with the exception of nanofibers formed from L-PRP prepared at 800 + 400× g, all other microenvironments were favorable for h-AdMSC proliferation. Here, we present a reproducible protocol for the standardization of L-PRP and fibrin nanofibers useful in clinical practices with known platelet/leukocyte ratios and in vitro evaluations that may predict in vivo results.


2020 ◽  
Vol 40 (3) ◽  
pp. 766-782 ◽  
Author(s):  
Jennifer Bordenave ◽  
Ly Tu ◽  
Nihel Berrebeh ◽  
Raphaël Thuillet ◽  
Amélie Cumont ◽  
...  

Objective: Excessive accumulation of resident cells within the pulmonary vascular wall represents the hallmark feature of the remodeling occurring in pulmonary arterial hypertension (PAH). Furthermore, we have previously demonstrated that pulmonary arterioles are excessively covered by pericytes in PAH, but this process is not fully understood. The aim of our study was to investigate the dynamic contribution of pericytes in PAH vascular remodeling. Approach and Results: In this study, we performed in situ, in vivo, and in vitro experiments. We isolated primary cultures of human pericytes from controls and PAH lung specimens then performed functional studies (cell migration, proliferation, and differentiation). In addition, to follow up pericyte number and fate, a genetic fate-mapping approach was used with an NG2CreER;mT/mG transgenic mice in a model of pulmonary arteriole muscularization occurring during chronic hypoxia. We identified phenotypic and functional abnormalities of PAH pericytes in vitro, as they overexpress CXCR (C-X-C motif chemokine receptor)-7 and TGF (transforming growth factor)-βRII and, thereby, display a higher capacity to migrate, proliferate, and differentiate into smooth muscle-like cells than controls. In an in vivo model of chronic hypoxia, we found an early increase in pericyte number in a CXCL (C-X-C motif chemokine ligand)-12-dependent manner whereas later, from day 7, activation of the canonical TGF-β signaling pathway induces pericytes to differentiate into smooth muscle-like cells. Conclusions: Our findings reveal a pivotal role of pulmonary pericytes in PAH and identify CXCR-7 and TGF-βRII as 2 intrinsic abnormalities in these resident progenitor vascular cells that foster the onset and maintenance of PAH structural changes in blood lung vessels.


2021 ◽  
Vol 22 (23) ◽  
pp. 13136
Author(s):  
Han Seok Koh ◽  
SangJoon Lee ◽  
Hyo Jin Lee ◽  
Jae-Woong Min ◽  
Takeshi Iwatsubo ◽  
...  

Alzheimer’s disease (AD) is a form of dementia characterized by progressive memory decline and cognitive dysfunction. With only one FDA-approved therapy, effective treatment strategies for AD are urgently needed. In this study, we found that microRNA-485-3p (miR-485-3p) was overexpressed in the brain tissues, cerebrospinal fluid, and plasma of patients with AD, and its antisense oligonucleotide (ASO) reduced Aβ plaque accumulation, tau pathology development, neuroinflammation, and cognitive decline in a transgenic mouse model of AD. Mechanistically, miR-485-3p ASO enhanced Aβ clearance via CD36-mediated phagocytosis of Aβ in vitro and in vivo. Furthermore, miR-485-3p ASO administration reduced apoptosis, thereby effectively decreasing truncated tau levels. Moreover, miR-485-3p ASO treatment reduced secretion of proinflammatory cytokines, including IL-1β and TNF-α, and eventually relieved cognitive impairment. Collectively, our findings suggest that miR-485-3p is a useful biomarker of the inflammatory pathophysiology of AD and that miR-485-3p ASO represents a potential therapeutic candidate for managing AD pathology and cognitive decline.


2012 ◽  
Vol 80 (8) ◽  
pp. 2835-2846 ◽  
Author(s):  
Cathryn Kurkjian ◽  
Melissa Hollifield ◽  
J. Louise Lines ◽  
Amy Rogosky ◽  
Kerry M. Empey ◽  
...  

ABSTRACTPneumocystispneumonia was first diagnosed in malnourished children and has more recently been found in children with upper respiratory symptoms. We previously reported that there is a significant delay in the immune response in newborn mice infected withPneumocystiscompared to adults (Garvy BA, Harmsen AG, Infect. Immun. 64:3987–3992, 1996, and Garvy BA, Qureshi M, J. Immunol. 165:6480–6486, 2000). This delay is characterized by the failure of neonatal lungs to upregulate proinflammatory cytokines and attract T cells into the alveoli. Here, we report that regardless of the age at which we infected the mice, they failed to mount an inflammatory response in the alveolar spaces until they were 21 days of age or older. Anti-inflammatory cytokines had some role in dampening inflammation, since interleukin-10 (IL-10)-deficient pups clearedPneumocystisfaster than wild-type pups and the neutralization of transforming growth factor beta (TGF-β) with specific antibody enhanced T cell migration into the lungs at later time points. However, the clearance kinetics were similar to those of control pups, suggesting that there is an intrinsic deficiency in the ability of innate immunity to controlPneumocystis. We found, using an adoptive transfer strategy, that the lung environment contributes to association ofPneumocystisorganisms with alveolar macrophages, implying no intrinsic deficiency in the binding ofPneumocystisby neonatal macrophages. Using bothin vivoandin vitroassays, we found thatPneumocystisorganisms were less able to stimulate translocation of NF-κB to the nucleus of alveolar macrophages from neonatal mice. These data indicate that there is an early unresponsiveness of neonatal alveolar macrophages toPneumocystisinfection that is both intrinsic and related to the immunosuppressive environment found in neonatal lungs.


2021 ◽  
pp. 2101470
Author(s):  
Inés López-Alonso ◽  
Cecilia López-Martínez ◽  
Paula Martín-Vicente ◽  
Laura Amado-Rodríguez ◽  
Adrián González-López ◽  
...  

Mechanical stretch of cancer cells can alter their invasiveness. During mechanical ventilation, lungs may be exposed to an increased amount of stretch, but the consequences on lung tumors have not been explored. To characterize the influence of mechanical ventilation on the behavior of lung tumors, invasiveness assays and transcriptomic analyses were performed in cancer cell lines cultured in static conditions or under cyclic stretch. Mice harbouring lung melanoma implants were submitted to mechanical ventilation and metastatic spread was assessed. Additional in vivo experiments were performed to determine the mechano-dependent specificity of the response. Incidence of metastases was studied in a cohort of lung cancer patients that received mechanical ventilation compared with a matched group of non-ventilated patients. Stretch increases invasiveness in melanoma B16F10luc2 and lung adenocarcinoma A549 cells. We identified a mechanosensitive upregulation of pathways involved in cholesterol processing in vitro, leading to an increase in PCSK9 and LDLR expression, a decrease in intracellular cholesterol and preservation of cell stiffness. A course of mechanical ventilation in mice harboring melanoma implants increased brain and kidney metastases two weeks later. Blockade of PCSK9 using a monoclonal antibody increased cell cholesterol and stiffness and decreased cell invasiveness in vitro and metastasis in vivo. In patients, mechanical ventilation increased PCSK9 abundance in lung tumors and the incidence of metastasis, thus decreasing survival. Our results suggest that mechanical stretch promote invasiveness of cancer cells, which may have clinically relevant consequences. Pharmacological manipulation of cholesterol endocytosis could be a novel therapeutic target in this setting.


2005 ◽  
Vol 280 (43) ◽  
pp. 36510-36517 ◽  
Author(s):  
José M. Lora ◽  
Dong Mei Zhang ◽  
Sha Mei Liao ◽  
Timothy Burwell ◽  
Anne Marie King ◽  
...  

Excessive mucus production by airway epithelium is a major characteristic of a number of respiratory diseases, including asthma, chronic bronchitis, and cystic fibrosis. However, the signal transduction pathways leading to mucus production are poorly understood. Here we examined the potential role of IκB kinase β (IKKβ) in mucus synthesis in vitro and in vivo. Tumor necrosis factor-α (TNF-α) or transforming growth factor-α stimulation of human epithelial cells resulted in mucus secretion as measured by MUC5AC mRNA and protein. TNF-α stimulation induced IKKβ-dependent p65 nuclear translocation, mucus synthesis, and production of cytokines from epithelial cells. TNF-α, but not transforming growth factor-α, induced mucus production dependent on IKKβ-mediated NF-κB activation. In vivo, TNF-α induced NF-κB as determined by whole mouse body bioluminescence. This activation was localized to the epithelium as revealed by LacZ staining in NF-κB-LacZ transgenic mice. TNF-α-induced mucus production in vivo could also be inhibited by administration into the epithelium of an IKKβ dominant negative adenovirus. Taken together, our results demonstrated the important role of IKKβ in TNF-α-mediated mucus production in airway epithelium in vitro and in vivo.


2017 ◽  
Vol 95 (5) ◽  
pp. 537-548 ◽  
Author(s):  
Hanan Hosni Ahmed ◽  
Laila Ahmed Rashed ◽  
Sohair Mahfouz ◽  
Rania Elsayed Hussein ◽  
Marwa Alkaffas ◽  
...  

Our aim was to study the effect of platelet-rich plasma (PRP) on the proliferation of bone-marrow-derived mesenchymal stem cells (BM-MSCs) and to investigate their roles in the healing of experimental burn injury and the possible mechanism of action. Our work was divided into in-vitro and in-vivo studies. The in-vitro study included untreated MSCs and MSCs treated with PRP. Levels of TGF-β and cell proliferation were assessed. In the in-vivo study, 72 rats were distributed equally among 6 groups: control, burn, burn with MSCs, burn with PRP, burn with both MSCs and PRP, and burn with MSCs pretreated with PRP. On the 7th and 20th day after injury, the serum levels of transforming growth factor beta (TGF-β) and tumor necrosis factor alpha (TNF-α), as well as interleukin-10 (IL-10) levels in skin tissue were measured by ELISA; histopathology and gene expression of MMP-1, TIMP-2, Ang-1, Ang-2, and vimentin by real-time PCR were performed in all groups. In vitro: proliferation of MSCs and TGF-β increased in the PRP-treated group compared with the control group. In vivo: Ang-1, Ang-2, and vimentin were upregulated, whereas MMP-1 and TIMP-2 were downregulated. TGF-β and IL-10 were increased, whereas TNF-α was decreased in all treated groups with more significance in MSCs and PRP on day 20. Histopathology of burn skin was improved in all treated groups, particularly in MSCs pretreated with PRP 20 days post-burn.


2021 ◽  
Vol 12 (11) ◽  
Author(s):  
Shuang-Qing Liu ◽  
Chao Ren ◽  
Ren-Qi Yao ◽  
Yao Wu ◽  
Ying-Yi Luan ◽  
...  

AbstractTumor necrosis factor (TNF)-α-induced protein 8-like 2 (TIPE2) is a newly discovered negative immunoregulatory protein that is involved in various cellular immune responses to infections. However, the underlying mechanism by which TIPE2 affects the immune function of dendritic cells (DCs) is not yet understood. This study aimed to determine the correlations among DCs TIPE2 expression, autophagic activity and immune function in the context of sepsis. In addition, the signaling pathway by which TIPE2 regulates autophagy in DCs was investigated. We reported for the first time that TIPE2 overexpression (knock-in, KI) exerted an inhibitory effect on autophagy in DCs and markedly suppressed the immune function of DCs upon septic challenge both in vitro and in vivo. In addition, TIPE2 knockout (KO) in DCs significantly enhanced autophagy and improved the immune response of DCs in sepsis. Of note, we found that the transforming growth factor-β (TGF-β)-activated kinase-1 (TAK1)/c-Jun N-terminal kinase (JNK) pathway was inhibited by TIPE2 in DCs, resulting in downregulated autophagic activity. Collectively, these results suggest that TIPE2 can suppress the autophagic activity of DCs by inhibiting the TAK1/JNK signaling pathway and further negatively regulate the immune function of DCs in the development of septic complications.


2017 ◽  
Vol 5 ◽  
Author(s):  
Jianglin Tan ◽  
Jun Wu

Abstract Abnormal wound healing is likely to induce scar formation, leading to dysfunction, deformity, and psychological trauma in burn patients. Despite the advancement of medical care treatment, scar contracture in burn patients remains a challenge. Myofibroblasts play a key role in scar contracture. It has been demonstrated that myofibroblasts, as well as inflammatory cells, fibroblasts, endothelial cells, and epithelial cells, secrete transforming growth factor-β1 (TGF-β1) and other cytokines, which can promote persistent myofibroblast activation via a positive regulation loop. In addition to the cellular contribution, the microenvironments, including the mechanical tension and integrin family, are also involved in scar contracture. Most recently, eukaryotic initiation factor 6 (eIF6), an upstream regulator of TGF-β1, has been demonstrated to be involved in myofibroblast differentiation and contraction in both in vitro fibroblast-populated collagen lattice (FPCL) and in vivo external mechanical stretch models. Moreover, the data showed that P311 could induce the transdifferentiation of epidermal stem cells to myofibroblasts by upregulating TGF-β1 expression, which mediated myofibroblast contraction. In this review, we briefly described the most current progress on the biological function of myofibroblasts in scar contracture and subsequently summarized the molecular events that initiated contracture. This would help us better understand the molecular basis of scar contracture as well as to find a comprehensive strategy for preventing/managing scar contracture.


2021 ◽  
Vol 22 (4) ◽  
pp. 1985
Author(s):  
Xiaohe Li ◽  
Ling Ma ◽  
Kai Huang ◽  
Yuli Wei ◽  
Shida Long ◽  
...  

Idiopathic pulmonary fibrosis (IPF) is a fatal and age-related pulmonary disease. Nintedanib is a receptor tyrosine kinase inhibitor, and one of the only two listed drugs against IPF. Regorafenib is a novel, orally active, multi-kinase inhibitor that has similar targets to nintedanib and is applied to treat colorectal cancer and gastrointestinal stromal tumors in patients. In this study, we first identified that regorafenib could alleviate bleomycin-induced pulmonary fibrosis in mice. The in vivo experiments indicated that regorafenib suppresses collagen accumulation and myofibroblast activation. Further in vitro mechanism studies showed that regorafenib inhibits the activation and migration of myofibroblasts and extracellular matrix production, mainly through suppressing the transforming growth factor (TGF)-β1/Smad and non-Smad signaling pathways. In vitro studies have also indicated that regorafenib could augment autophagy in myofibroblasts by suppressing TGF-β1/mTOR (mechanistic target of rapamycin) signaling, and could promote apoptosis in myofibroblasts. In conclusion, regorafenib attenuates bleomycin-induced pulmonary fibrosis by suppressing the TGF-β1 signaling pathway.


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