scholarly journals Adipose Tissue-Derived Stem Cells Have the Ability to Differentiate into Alveolar Epithelial Cells and Ameliorate Lung Injury Caused by Elastase-Induced Emphysema in Mice

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Eriko Fukui ◽  
Soichiro Funaki ◽  
Kenji Kimura ◽  
Toru Momozane ◽  
Atsuomi Kimura ◽  
...  
Keyword(s):  
Stem Cells ◽  
Adipose Tissue ◽  
Epithelial Cells ◽  
Lung Injury ◽  
Alveolar Epithelial Cells ◽  
Chronic Obstructive ◽  
Alveolar Cells ◽  
Alveolar Epithelial

Chronic obstructive pulmonary disease is a leading cause of mortality globally, with no effective therapy yet established. Adipose tissue-derived stem cells (ADSCs) are useful for ameliorating lung injury in animal models. However, whether ADSCs differentiate into functional cells remains uncertain, and no study has reported on the mechanism by which ADSCs improve lung functionality. Thus, in this study, we examined whether ADSCs differentiate into lung alveolar cells and are able to ameliorate lung injury caused by elastase-induced emphysema in model mice. Here, we induced ADSCs to differentiate into type 2 alveolar epithelial cells in vitro. We demonstrated that ADSCs can differentiate into type 2 alveolar epithelial cells in an elastase-induced emphysematous lung and that ADSCs improve pulmonary function of emphysema model mice, as determined with spirometry and 129Xe MRI. These data revealed a novel function for ADSCs in promoting repair of the damaged lung by direct differentiation into alveolar epithelial cells.

CD40 amplifies Fas-mediated apoptosis: a mechanism contributing to emphysema

2012 ◽  
Vol 303 (2) ◽  
pp. L141-L151 ◽  
Author(s):  
Ayako Shigeta ◽  
Yuji Tada ◽  
Ji-Yang Wang ◽  
Shunsuke Ishizaki ◽  
Junichi Tsuyusaki ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Epithelial Cells ◽  
Pulmonary Emphysema ◽  
Alveolar Epithelial Cells ◽  
Alveolar Cells ◽  
Alveolar Epithelial ◽  
Cd40 Stimulation ◽  
Ifn Γ ◽  
Apoptosis And Inflammation

Excessive apoptosis and prolonged inflammation of alveolar cells are associated with the pathogenesis of pulmonary emphysema. We aimed to determine whether CD40 affects alveolar epithelial cells and endothelial cells, with regard to evoking apoptosis and inflammation. Mice were repeatedly treated with agonistic-anti CD40 antibody (Ab), with or without agonistic-anti Fas Ab, and evaluated for apoptosis and inflammation in lungs. Human pulmonary microvascular endothelial cells and alveolar epithelial cells were treated with agonistic anti-CD40 Ab and/or anti-Fas Ab to see their direct effect on apoptosis and secretion of proinflammatory molecules in vitro. Furthermore, plasma soluble CD40 ligand (sCD40L) level was evaluated in patients with chronic obstructive pulmonary disease (COPD). In mice, inhaling agonistic anti-CD40 Ab induced moderate alveolar enlargement. CD40 stimulation, in combination with anti-Fas Ab, induced significant emphysematous changes and increased alveolar cell apoptosis. CD40 stimulation also enhanced IFN-γ-mediated emphysematous changes, not via apoptosis induction, but via inflammation with lymphocyte accumulation. In vitro, Fas-mediated apoptosis was enhanced by CD40 stimulation and IFN-γ in endothelial cells and by CD40 stimulation in epithelial cells. CD40 stimulation induced secretion of CCR5 ligands in endothelial cells, enhanced with IFN-γ. Plasma sCD40L levels were significantly increased in patients with COPD, inversely correlating to the percentage of forced expiratory volume in 1 s and positively correlating to low attenuation area score by CT scan, regardless of smoking history. Collectively CD40 plays a contributing role in the development of pulmonary emphysema by sensitizing Fas-mediated apoptosis in alveolar cells and increasing the secretion of proinflammatory chemokines.

scholarly journals Radiation Induces Pulmonary Fibrosis by Promoting the Fibrogenic Differentiation of Alveolar Stem Cells

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Lu-Kai Wang ◽  
Tsai-Jung Wu ◽  
Ji-Hong Hong ◽  
Fang-Hsin Chen ◽  
John Yu ◽  
...  
Keyword(s):  
Stem Cells ◽  
Epithelial Cells ◽  
Epithelial Mesenchymal Transition ◽  
Tissue Growth ◽  
Alveolar Epithelial Cells ◽  
Type I ◽  
Alveolar Cells ◽  
Mesenchymal Transition ◽  
Alveolar Epithelial ◽  
Radiation Induced

The lung is a radiosensitive organ, which imposes limits on the therapeutic dose in thoracic radiotherapy. Irradiated alveolar epithelial cells promote radiation-related pneumonitis and fibrosis. However, the role of lung stem cells (LSCs) in the development of radiation-induced lung injury is still unclear. In this study, we found that both LSCs and LSC-derived type II alveolar epithelial cells (AECII) can repair radiation-induced DNA double-strand breaks, but the irradiated LSCs underwent growth arrest and cell differentiation faster than the irradiated AECII cells. Moreover, radiation drove LSCs to fibrosis as shown with the elevated levels of markers for epithelial-mesenchymal transition and myofibroblast (α-smooth muscle actin (α-SMA)) differentiation in in vitro and ex vivo studies. Increased gene expressions of connective tissue growth factor and α-SMA were found in both irradiated LSCs and alveolar cells, suggesting that radiation could induce the fibrogenic differentiation of LSCs. Irradiated LSCs showed an increase in the expression of surfactant protein C (SP-C), the AECII cell marker, and α-SMA, and irradiated AECII cells expressed SP-C and α-SMA. These results indicated that radiation induced LSCs to differentiate into myofibroblasts and AECII cells; then, AECII cells differentiated further into either myofibroblasts or type I alveolar epithelial cells (AECI). In conclusion, our results revealed that LSCs are sensitive to radiation-induced cell damage and may be involved in radiation-induced lung fibrosis.

Role Of The Type 2 Alveolar Epithelial Cells In An Experimental Model Of Acute Lung Injury

2012 ◽  
Author(s):  
Sonia Garcia-Hernandez ◽  
Ricardo Gutierrez ◽  
Lucio Diaz-Flores ◽  
Jesus Villar ◽  
Francisco Valladares
Keyword(s):  
Acute Lung Injury ◽  
Epithelial Cells ◽  
Lung Injury ◽  
Experimental Model ◽  
Alveolar Epithelial Cells ◽  
Alveolar Epithelial

Reticulocalbin 3 deficiency in alveolar epithelium attenuated LPS-induced ALI via NF-κB signaling

2021 ◽  
Vol 320 (4) ◽  
pp. L627-L639
Author(s):  
Xiaoqian Shi ◽  
Xiaojie An ◽  
Liu Yang ◽  
Zhipeng Wu ◽  
Danni Zan ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Lung Injury ◽  
Inflammatory Response ◽  
Secretory Pathway ◽  
Alveolar Epithelium ◽  
Repair Process ◽  
Alveolar Epithelial Cells ◽  
Alveolar Epithelial

Acute respiratory distress syndrome (ARDS) is characterized by acute lung injury (ALI) secondary to an excessive alveolar inflammatory response. Reticulocalbin 3 (Rcn3) is an endoplasmic reticulum (ER) lumen protein in the secretory pathway. We previously reported the indispensable role of Rcn3 in type II alveolar epithelial cells (AECIIs) during lung development and the lung injury repair process. In the present study, we further observed a marked induction of Rcn3 in the alveolar epithelium during LPS-induced ALI. In vitro alveolar epithelial (MLE-12) cells consistently exhibited a significant induction of Rcn3 accompanied with NF-κB activation in response to LPS exposure. We examined the role of Rcn3 in the alveolar inflammatory response by using mice with a selective deletion of Rcn3 in alveolar epithelial cells upon doxycycline administration. The Rcn3 deficiency significantly blunted the ALI and alveolar inflammation induced by intratracheal LPS instillation but not that induced by an intraperitoneal LPS injection (secondary insult); the alleviated ALI was accompanied by decreases in NF-κB activation and NLRP3 levels but not in GRP78 and cleaved caspase-3 levels. The studies conducted in MLE-12 cells consistently showed that Rcn3 knockdown blunted the activations of NF-κB signaling and NLRP3-dependent inflammasome upon LPS exposure. Collectively, these findings suggest a novel role for Rcn3 in regulating the alveolar inflammatory response to pulmonary infection via the NF-κB/NLRP3/inflammasome axis and shed additional light on the mechanism of ARDS/ALI.

scholarly journals Exosomes Derived From Alveolar Epithelial Cells Promote Alveolar Macrophage Activation Mediated by miR-92a-3p in Sepsis-Induced Acute Lung Injury

2021 ◽  
Vol 11 ◽  
Author(s):  
Fen Liu ◽  
Wei Peng ◽  
Jiaquan Chen ◽  
Zeyao Xu ◽  
Rong Jiang ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Epithelial Cells ◽  
Lung Injury ◽  
Pulmonary Inflammation ◽  
Cecal Ligation ◽  
Alveolar Epithelial Cells ◽  
Luciferase Reporter ◽  
Alveolar Epithelial

Acute lung injury (ALI) induced by sepsis is characterized by disruption of the epithelial barrier and activation of alveolar macrophages (AMs), which leads to uncontrolled pulmonary inflammation. However, effective treatments for ALI are unavailable. The exact mechanism by which the initial mediator of alveolar epithelial cells (AECs) induces inflammation remains elusive. Here we investigated the roles of AEC-derived exosomes in AM activation and sepsis-induced ALI in vivo and in vitro. Cecal ligation and puncture (CLP) was utilized to establish septic lung injury model in rats. The effect of exosomal inhibition by intratracheal GW4869 administration on lung injury was investigated. To assess the effects of AEC-derived exosomes on ALI, we treated the rat alveolar epithelial cell line RLE-6TN with LPS to induce cell damage. Exosomes from conditioned medium of LPS-treated AECs (LPS-Exos) were isolated by ultracentrifugation. The miRNAs in LPS-Exos were screened by miRNA expression profile analysis. The effects of miR-92a-3p on the function of AMs were studied. We found that intratracheal GW4869 administration ameliorated lung injury following CLP-induced ALI. LPS-Exos were taken up by AMs and activated these cells. Consistently, administration of LPS-Exos in rats significantly aggravated pulmonary inflammation and alveolar permeability. Moreover, miR-92a-3p was enriched in LPS-Exos and could be delivered to AMs. Inhibition of miR-92a-3p in AECs diminished the proinflammatory effects of LPS-Exos in vivo and in vitro. Mechanistically, miR-92a-3p activates AMs along with pulmonary inflammation. This process results in activation of the NF-κB pathway and downregulation of PTEN expression, which was confirmed by a luciferase reporter assay. In conclusion, AEC-derived exosomes activate AMs and induce pulmonary inflammation mediated by miR-92a-3p in ALI. The present findings revealed a previously unidentified role of exosomal miR-92a-3p in mediating the crosstalk between injured AEC and AMs. miR-92a-3p in AEC exosomes might represent a novel diagnostic biomarker for ALI, which may lead to a new therapeutic approach.

Sign in / Sign up

Export Citation Format

Share Document