Mitochondrial superoxide dismutase induction does not protect epithelial cells during oxidant exposure in vitro

1995 ◽  
Vol 268 (1) ◽  
pp. L71-L77 ◽  
Author(s):  
V. L. Kinnula ◽  
P. Pietarinen ◽  
K. Aalto ◽  
I. Virtanen ◽  
K. O. Raivio

The significance of manganese superoxide dismutase (MnSOD) induction in cells and tissues during oxidant stress is still poorly understood. In this study, transformed human bronchial epithelial cells (BEAS 2B) were treated with interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), or with combination of these cytokines (10 ng/ml concentrations) for 48 or 72 h and exposed to selected oxidants. TNF-alpha and IFN-gamma + TNF-alpha combination resulted in a marked increase of MnSOD protein and MnSOD activity. When cells pretreated with the cytokines were exposed to hyperoxia (95% O2, 72 h), menadione (5-50 microM, 4 h), or H2O2 (0.5 and 5 mM, 4 h), in all cases IFN-gamma and TNF-alpha enhanced oxidant-related cell injury. The effect was most significant with cells pretreated with a combination of IFN-gamma and TNF-alpha. Antioxidant enzymes such as total SOD, glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase did not change significantly during the cytokine treatment. Catalase activity was not changed by IFN-gamma or TNF-alpha but it decreased significantly (34%) in IFN-gamma + TNF-alpha-treated cells. Free radical generation was not changed by these cytokines in acute (30 min) experimental conditions or after 48-h treatment. These results suggest that cytokine-induced MnSOD does not protect bronchial epithelial cells against endogenously or exogenously generated oxidants in vitro. In fact, cells that contained the highest MnSOD activity were the most sensitive to subsequent oxidant damage.

1996 ◽  
Vol 270 (1) ◽  
pp. L80-L87 ◽  
Author(s):  
P. G. Bloemen ◽  
M. C. Van den Tweel ◽  
P. A. Henricks ◽  
F. Engels ◽  
M. J. Van de Velde ◽  
...  

It has become clear that the bronchial epithelium is not just a passive barrier but plays an active role in inflammation. It can produce several inflammatory mediators and does express cell adhesion molecules of which intercellular adhesion molecule (ICAM)-1 can be upregulated by cytokines like interferon (IFN)-gamma. In the present study, we analyzed in detail the interaction of neutrophils with human bronchial epithelial cells, both primary cultured cells and the bronchial epithelial cell line BEAS-2B. Confluent monolayers of epithelial cells were incubated with freshly isolated 51Cr-labeled neutrophils for 30 min at 37 degrees C; then the nonadherent cells were removed by washing gently. Stimulation of the epithelial cells with IFN-gamma or the combination of IFN-gamma and tumor necrosis factor-alpha (TNF-alpha) (which doubles the ICAM-1 expression) increased neutrophil adhesion. Activation of the neutrophils themselves with N-formylmethionyl-leucyl-phenylalanine (fMLP), platelet-activating factor, or TNF-alpha also caused a profound enhancement of the adhesion. A significant additional increase was found when the epithelial cells had been exposed to IFN-gamma and the neutrophils were stimulated with fMLP simultaneously. This effect was even more pronounced with epithelium preincubated with IFN-gamma and TNF-alpha. With the use of monoclonal antibodies against CD18 and ICAM-1, it was demonstrated that the increased adhesion was mainly mediated by the ICAM-1/beta 2-integrin interaction. This study highlights that both the activation state of the bronchial epithelial cells and the activation state of the neutrophils are critical for their interactive adhesion.


2021 ◽  
Author(s):  
Maysa A R Brandao-Rangel ◽  
Dobroslav Melamed ◽  
Anamei Silva-Reis ◽  
Boris Brill ◽  
Lucas dos Santos Zamarioli ◽  
...  

Coronavirus disease 2019 (COVID-19), which is currently a global public health emergency and beyond vaccines as a prophylactic treatment, no specific and effective therapeutical treatments are available. COVID-19 induces a massive release of proinflammatory cytokines, which drives COVID-19 progression, severity, and mortality. In addition, bronchial epithelial cells are the first pulmonary cells activated by coronavirus-2 (SARS-Cov-2) leading to massive cytokine release, which can hyperactivate lung fibroblasts, resulting in pulmonary fibrosis, a phenomenon observed even in moderate COVID-19 survivors. This in vitro study tested the hypothesis that Virlaza, a herbal medicine, could inhibit the hyperactivation of human bronchial epithelial cells (BEAS-2B) and pulmonary fibroblasts (MRC-5) induced by SARS-Cov-2. BEAS-2B (5x104/mL/well) and MRC-5 (5x104/mL/well) cells were co-cultivated with 1ml of blood of a Sars-Cov-2 infected patient for 4 hours and Virlaza (1ug/mL) was added in the first minute of the co-culture. After 4 hours, the cells were recovered and used for analysis of cytotoxicity by MTT and for mRNA expression of P2X7 receptor E iNOS. The supernatant was used to measure ATP and cytokines. Sars-Cov-2 incubation resulted in increased release of ATP, IL-1beta, IL-6, IL-8, and TNF-alpha by BEAS-2B and MRC-5 cells (p<0.001). Treatment with Virlaza resulted in reduction of ATP, IL-1beta, IL-6, IL-8, and TNF-alpha release (p<0.001). In addition, Sars-Cov-2 incubation resulted in increased expression of P2X7 receptor and iNOS (p<0.001), which has been reversed by Virlaza (p<0.001). In conclusion, Virlaza presents important anti-inflammatory effects in the context of Sars-Cov-2 infection.


2012 ◽  
Vol 130 (6) ◽  
pp. 1375-1383 ◽  
Author(s):  
Jin-Ah Park ◽  
Asma S. Sharif ◽  
Daniel J. Tschumperlin ◽  
Laurie Lau ◽  
Rachel Limbrey ◽  
...  

Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 631
Author(s):  
Luis Soriano ◽  
Tehreem Khalid ◽  
Fergal J. O'Brien ◽  
Cian O'Leary ◽  
Sally-Ann Cryan

Translation of novel inhalable therapies for respiratory diseases is hampered due to the lack of in vitro cell models that reflect the complexity of native tissue, resulting in many novel drugs and formulations failing to progress beyond preclinical assessments. The development of physiologically-representative tracheobronchial tissue analogues has the potential to improve the translation of new treatments by more accurately reflecting in vivo respiratory pharmacological and toxicological responses. Herein, advanced tissue-engineered collagen hyaluronic acid bilayered scaffolds (CHyA-B) previously developed within our group were used to evaluate bacterial and drug-induced toxicity and inflammation for the first time. Calu-3 bronchial epithelial cells and Wi38 lung fibroblasts were grown on either CHyA-B scaffolds (3D) or Transwell® inserts (2D) under air liquid interface (ALI) conditions. Toxicological and inflammatory responses from epithelial monocultures and co-cultures grown in 2D or 3D were compared, using lipopolysaccharide (LPS) and bleomycin challenges to induce bacterial and drug responses in vitro. The 3D in vitro model exhibited significant epithelial barrier formation that was maintained upon introduction of co-culture conditions. Barrier integrity showed differential recovery in CHyA-B and Transwell® epithelial cultures. Basolateral secretion of pro-inflammatory cytokines to bacterial challenge was found to be higher from cells grown in 3D compared to 2D. In addition, higher cytotoxicity and increased basolateral levels of cytokines were detected when epithelial cultures grown in 3D were challenged with bleomycin. CHyA-B scaffolds support the growth and differentiation of bronchial epithelial cells in a 3D co-culture model with different transepithelial resistance in comparison to the same co-cultures grown on Transwell® inserts. Epithelial cultures in an extracellular matrix like environment show distinct responses in cytokine release and metabolic activity compared to 2D polarised models, which better mimic in vivo response to toxic and inflammatory stimuli offering an innovative in vitro platform for respiratory drug development.


Sign in / Sign up

Export Citation Format

Share Document