Irreversible destruction of bronchi and alveoli can lead to multiple incurable lung diseases. Identifying lung stem/progenitor cells with regenerative capacity and utilizing them to reconstruct functional tissue is one of the biggest hopes to reverse the damage and cure such diseases. Here we showed that a rare population of SOX9 basal cells (BCs) located at airway epithelium rugae can regenerate adult human lung. Human SOX9 BCs can be readily isolated by bronchoscopic brushing and indefinitely expanded in feeder-free condition. Expanded human SOX9 BCs can give rise to alveolar and bronchiolar epithelium after being transplanted into injured mouse lung, with air-blood exchange system reconstructed and recipient's lung function improved. Manipulation of lung microenvironment with Pirfenidone to suppress TGF-β signaling could further boost the transplantation efficiency. Moreover, we conducted the first autologous SOX9 BCs transplantation clinical trial in two bronchiectasis patients. Lung tissue repair and pulmonary function enhancement was observed in patients 3-12 months after cell transplantation. Altogether our current work indicated that functional adult human lung structure can be reconstituted by orthotopic transplantation of tissue-specific stem/progenitor cells, which could be translated into a mature regenerative therapeutic strategy in near future.
Bronchiectasis ; genetics ; metabolism ; Humans ; Pulmonary Alveoli ; cytology ; metabolism ; SOX9 Transcription Factor ; genetics ; metabolism ; Stem Cell Transplantation ; methods ; Stem Cells ; cytology ; metabolism

In the study, the effects of Panax notoginseng saponins (PNS) on alveolar epithelial to mesenchymal transition (EMT) and extracellular matrix degradation were observed in a type of human alveolar epithelial cell, A549 cells, stimulated by TGF-beta1. Firstly, MTT method was applied to evaluation of cellular proliferation and found that PNS from 12.5 mg x L(-1) to 200 mg x L(-1) dosage could not inhibit significantly cellular proliferation. Then, cells were divided into five groups, normal group, TGF-beta1 group, TGF-beta1 + 50 mg x L(-1) PNS group, TGF-beta1 + 100 mg x L(-1) PNS group and TGF-beta1 + 200 mg x L(-1) PNS group. Normal cells were not stimulatec by TGF-beta1; TGF-beta1 cells were only stimulated by TGF-beta1 and the other cells were stimulated by TGF-beta1 with different doses of PNS, respectively. After stimulation, cells and supernatants were collected for assays. Cellular roundness was applied to quantitative evaluation of morphological change. Immunocytochemistry was applied to examine E-cadherion, a-SMA and FN proteins expression in the cells. Enzyme linked-immunosorbent assay was applied to MMP-9 and TIMP-1 levels. The results showed that EMT of A549 cells was induced by TGF-beta1, showing significant change of roundness, E-cadherion, alpha-SMA and FN (P < 0.05, P < 0.01). Compared to TGF-beta1, PNS significantly inhibited the changes of roundness (P < 0.05), FN and alpha-SMA (P < 0.05, P < 0.01) and not significantly inhibited the change of E-cadherion. Furthermore, MMP-9 levels were significantly increased by TGFbeta1 stimulation (P < 0.05), without significant change of TIMP-1. Compared with TGF-beta1, PNS could significantly increase MMP-9 level (P < 0.05) and decrease TIMP-1 levels (P < 0.05, P < 0.01). In conclusion, PNS could inhibit alveolar epithelial cell EMT induced by TGF-beta1, with increase of extracellular matrix degradation ability, which showed anti-fibrosis of lung ability.
Cell Proliferation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Epithelial-Mesenchymal Transition ; drug effects ; Humans ; Matrix Metalloproteinase 9 ; metabolism ; Panax notoginseng ; chemistry ; Pulmonary Alveoli ; cytology ; drug effects ; metabolism ; Saponins ; pharmacology ; Transforming Growth Factor beta1 ; metabolism

OBJECTIVETo explore the roles of PKCβ/P66Shc oxidative stress signal pathway in mediating hyperoxia-induced reactive oxgen species (ROS) production in alveolar epithelial cells (A549) and the protective effects of PKCβ inhibitor on hyperoxia-induced injuries of alveolar epithelial cells.

METHODSA549 cells were cultured in vitro and randomly divided into three groups: control, hyperoxia and PKCβ inhibitor LY333531 treatment. The hyperoxia group was exposed to a mixture of O2 (950 mL/L) and CO2 (50 mL/L) for 10 minutes and then cultured in a closed environment. The LY333531 group was treated with PKCβ inhibitor LY333531 of 10 µmol/L for 24 hours before hyperoxia induction. Cells were collected 24 hours after culture and the levels of PKCβ, Pin1, P66Shc and P66Shc-Ser36 were detected by Western blot. The intracellular translocation of P66Shc, the production of ROS and cellular mitochondria membrane potential were measured using the confocal microscopy.

RESULTSCompared with the control group, the levels of PKCβ, Pin1, P66Shc and P-P66Shc-Ser36 in A549 cells 24 hours after culture increased significantly in the hyperoxia group. These changes in the hyperoxia group were accompanied with an increased translocation rate of P66Shc from cytoplasm into mitochondria, an increased production of mitochondrial ROS, and a reduced mitochondrial membrane potential. Compared with the hyperoxia group, the levels of Pin1, P66Shc and P66Shc-Ser36 in A549 cells, the translocation rate of P66Shc from cytoplasm into mitochondria and the production of mitochondrial ROS decreased significantly, while the mitochondrial membrane potential increased significantly in the LY333531 treatment group. However, there were significant differences in the above mentioned measurements between the LY333531 treatment and control groups.

CONCLUSIONSHyperoxia can increase the expression of PKCβ in alveolar epithelial cells and production of mitochondrial ROS and decrease mitochondrial membrane potential. PKCβ inhibitor LY333531 can partially disrupt these changes and thus alleviate the hyperoxia-induced alveolar epithelial cell injury.

Cell Hypoxia ; Cells, Cultured ; Epithelial Cells ; metabolism ; Humans ; Indoles ; pharmacology ; Maleimides ; pharmacology ; Oxidative Stress ; Protein Kinase C beta ; physiology ; Pulmonary Alveoli ; cytology ; metabolism ; Reactive Oxygen Species ; metabolism ; Shc Signaling Adaptor Proteins ; physiology ; Signal Transduction ; physiology ; Src Homology 2 Domain-Containing, Transforming Protein 1

OBJECTIVETo investigate the protective effect of curcumin (CU) on type II alveolar epithelial cells (A549 cells) during paraquat (PQ)-induced oxidative damage and its underlying mechanism.

METHODSRoutinely cultured A549 cells were divided into blank control group, CU control group, PQ group, and PQ+Cu group to receive respective treatments for 24 h. Cell viability was determined by MTT assay. The NFE2L2 expression in A549 cells was measured by RT-PCR and Western blot. The activities of the heme oxygenase-1 (HO-1) and NAD (P) H: quinone oxidoreductase 1 (NQO-1) in cells and the superoxide dismutase (SOD) and catalase (CAT) in supernatant, as well as malondialdehyde (MDA) content, were measured by enzyme-linked immunosorbent assay. After siRNA depletion of Nrf2, the protective effect of CU on A549 cells during PQ-induced oxidative damage was evaluated.

RESULTSPQ, even at a dose of 0.1 mmol/L, could significantly suppress the viability of A549 cells in a dose-dependent manner. CU showed no significant inhibitory effect on the viability of A549 cells when given at a dose below 160 ümol/L. Compared with the blank control group, the PQ group had significantly decreased SOD activity and significantly increased CAT activity and MDA content after 24-h exposure to 800 ümol/L PQ (P < 0.05 or P < 0.01). Thanks to pretreatment with 80 ümol/L CU, the PQ+CU group had significantly increased SOD and CAT activities and significantly decreased MDA content compared with the PQ group (P < 0.01). Compared with the blank control group, the PQ group had significantly increased expression of NFE2L2 and its downstream factors HO-1 and NQO-1 (P < 0.01), while the PQ+CU group had significantly higher expression of NFE2L2, HO-1,and NQO-1 than the PQ group (P < 0.01).Compared with the PQ+CU group, the CU+PQ+NFE2L2siRNA group had significantly decreased SOD and CAT activities and significantly increased MDA content (P < 0.01).

CONCLUSIONLow-dose CU significantly reduces the PQ-induced oxidative damage in A549 cells in vitro by activation of the Nrf2-ARE pathway.

Cell Line ; Curcumin ; pharmacology ; Humans ; NF-E2-Related Factor 2 ; metabolism ; Oxidation-Reduction ; Oxidative Stress ; Paraquat ; toxicity ; Pulmonary Alveoli ; cytology ; metabolism ; Reactive Oxygen Species ; metabolism ; Superoxide Dismutase ; metabolism

This study is to investigate the effect of artesunate on transforming growth factor-beta1 (TGF-beta1) induced epithelial-mesenchymal transition (EMT) and its possible mechanism. After the in vitro cultured RLE-6TN cells were treated with TGF-beta1 then artesunate intervened on it, after 24 h, expression of the markers of mesenchymal cell was assayed using Western blotting and real-time PCR analysis. Western blotting was also used to detect the effect of TGF-beta1 on the Smad3 and Smad7 expressions of RLE-6TN cells. Morphological alterations were examined by phase-contrast microscope, and ultrastructure changes by electron microscope. Incubation of RLE-6TN cells with TGF-beta1 resulted in the up-regulation of the expression of the mesenchymal cell markers, after artesunate intervened on it, resulted in the down-regulation of the expression. Meanwhile, incubation with artesunate intervened on RLE-6TN cells could lead to the apparent down-regulation of the expression of Smad3 and up-regulation of Samd7 and the transition of RLE-6TN cells to mesenchymal-like by TGF-beta1 induction, after artesunate intervened on it, RLE-6TN cells to epithelial-like. TGF-beta1 induced epithelial-mesenchymal transition process; artesunate can inhibit TGF-beta1-induced epithelial-mesenchymal transition process, the possible mechanism is up-regulation of the expression of Smad7 and down-regulation of the expression of Smad3, meanwhile inhibits phosphorylation of Smad3.
Actins ; genetics ; metabolism ; Animals ; Artemisia ; chemistry ; Artemisinins ; isolation & purification ; pharmacology ; Cell Line ; Cell Proliferation ; drug effects ; Epithelial Cells ; cytology ; metabolism ; Epithelial-Mesenchymal Transition ; drug effects ; Idiopathic Pulmonary Fibrosis ; pathology ; Plants, Medicinal ; chemistry ; Pulmonary Alveoli ; cytology ; RNA, Messenger ; metabolism ; Rats ; Smad3 Protein ; genetics ; metabolism ; Smad7 Protein ; genetics ; metabolism ; Transforming Growth Factor beta1 ; pharmacology ; Vimentin ; genetics ; metabolism

OBJECTIVETo investigate the effects of cysteinyl leukotriene (CysLT) receptor agonist leukotriene D4 (LTD4) on proliferation and migration in lung epithelial A549 cells.

METHODSThe expression of CysLT1 receptor and CysLT2 receptor was determined by immunofluoresence staining in A549 cells. A549 cells were treated with LTD4 (0.01-100 nmol/L) for 24-72 h. Cell viability was detected by MTT reduction assay. Cell migration was determined by modified scratch and healing model.

RESULTSIn A549 cells, CysLT1 receptor and CysLT2 receptor were mainly expressed in the cytoplasm, membrane and few in the nuclei. The treatment of LTD4 (0.01-100 nmol/L) for 24-72 h caused no effect on cell viability (Ps>0.05); when A549 cells were treated with 100 nmol/L LTD4 for 24, 48 and 72 h the cell viability was (103.00±4.46)%，(107.00±9.45)% and (105.00±9.02)% of control, respectively (Ps>0.05). The migration rate of A549 cells after scratching during the first 24 h was markedly greater than that during the second and third 24 h in the same concentration groups; however, no significant difference in migration rate was noticed when the cells were treated with different concentrations of LTD4 (0.01-100 nmol/L)(Ps>0.05). The migration of A549 cells was 1.15-fold, 1.21-fold and 1.06-fold of that of control when the cells were treated with 100 nmol/L LTD4 for 24, 48 and 72 h, respectively (Ps>0.05).

CONCLUSIONThe proliferation and migration of A549 cells are not changed when treated with 0.01-100 nmol LTD4 for up to 72h.

Cell Line ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Epithelial Cells ; cytology ; drug effects ; Humans ; Leukotriene D4 ; pharmacology ; Pulmonary Alveoli ; cytology

Alveolar epithelial type II (AT II) cells are essential for lung development and remodeling, as they are precursors for type I cells and also produce other non-repair cells (fibroblasts). Progenitor cells are believed to possess capability of multi-potent transdifferentiation, which is closely related to the niche, suggesting the importance of establishment of a lung progenitor cell niche model. We hypothesized that pulmonary surfactant-associated protein A (SPA) suicide gene system would cause AT II cell to kill itself through apoptosis and leave its niche. In vitro, the recombinant adeno-associated virus vectors-SPA-thymidine kinase (rAAV-SPA-TK) system was established to get targeted apoptotic AT II cells. The apoptosis of AT II cells was detected by using MTT. The results showed that cloned SPA gene promoter had specific transcriptional activity in SPA high expression cells, and SPA high expression cells (H441) transfected with TK gene had higher sensitivity to ganciclovir (GCV) than SPA low expression cells (A549). In vivo, increased apoptosis of AT II cells induced by GCV in rAAV-SPA-TK system was observed by TUNEL. Finally, the successful packaging and application of rAAV-SPA-TK system provide experimental basis to get specific lung progenitor cell (AT II) niche in vitro and in vivo.
Antiviral Agents ; pharmacology ; Apoptosis ; drug effects ; Cell Line, Tumor ; Cell Survival ; drug effects ; Cells, Cultured ; Dependovirus ; genetics ; Dose-Response Relationship, Drug ; Electrophoresis, Polyacrylamide Gel ; Epithelial Cells ; cytology ; drug effects ; metabolism ; Ganciclovir ; pharmacology ; Gene Expression Regulation, Neoplastic ; Genes, Transgenic, Suicide ; genetics ; Genetic Vectors ; genetics ; Humans ; In Situ Nick-End Labeling ; Luciferases ; genetics ; metabolism ; Promoter Regions, Genetic ; genetics ; Pulmonary Alveoli ; cytology ; metabolism ; Pulmonary Surfactant-Associated Protein A ; genetics ; metabolism ; Thymidine Kinase ; genetics ; metabolism

OBJECTIVETo investigate the protective effect of hydrogen against hyperoxia-induced oxidative stress injury in premature rat type II alveolar epithelial cells (AECs).

METHODSThe type II AECs isolated from premature rats were randomly divided into air (21% oxygen) control group, hyperoxia (95% oxygen) control group, air + hydrogen group, and hyperoxia+ hydrogen group. The cells with hydrogen treatment were cultured in the presence of rich hydrogen. After the corresponding exposure for 24 h, the cell morphology was observed microscopically. MTT assay was used to evaluated the cell proliferation ability, and JC-1 fluorescence probe was used to detect the mitochondrial membrane potential (δφ) changes of the type II AECs. The concentration of maleic dialdehyde (MDA) and superoxide dismutase (SOD) activity in the cell supernatant were detected using colorimetric method.

RESULTSNo significant differences were found in cell growth or measurements between air control and air + hydrogen groups. Compared with air control group, the cells exposed to hyperoxia showed significantly suppressed proliferation, reduced mitochondrial membrane potential, increased MDA content, and decreased SOD activity. Intervention with hydrogen resulted in significantly increased cell proliferation and SOD activity and lowered MDA content, and restored the mitochondrial membrane potential in the cells with hyperoxia exposure (P<0.05).

CONCLUSIONHydrogen can significantly reduce hyperoxia-induced oxidative stress injury in premature rat type II AECs, improve the cellular antioxidant capacity, stabilize the mitochondrial membrane potential, and reduce the inhibitory effect of hyperoxia on cell proliferation.

Animals ; Animals, Newborn ; Antioxidants ; metabolism ; Cell Proliferation ; Cells, Cultured ; Epithelial Cells ; drug effects ; Female ; Hydrogen ; pharmacology ; Male ; Malondialdehyde ; metabolism ; Membrane Potential, Mitochondrial ; Oxidative Stress ; drug effects ; Oxygen ; adverse effects ; Pulmonary Alveoli ; cytology ; Rats ; Rats, Sprague-Dawley ; Superoxide Dismutase ; metabolism

OBJECTIVETo investigate the effects of Matrigel on expression of focal adhesion kinase and on proliferation and apoptosis of alveolar epithelial cell II of premature rat exposed to hyperoxia.

METHODSThe primary premature rat AECII (gestation 19 d) were cultured in vitro. For establishing hyperoxia-exposed cell model, purified AECII were cultured for 12 hours after culture flasks were filled with 95% oxygen-5% CO2 at 5 L/min, and then sealed for 12 hours. DNA content, phosphor and total protein of FAK were detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blotting respectively after 12 hours of air or hyperoxia exposure in the presence or absence of Matrigel. To investigate the relationship between FAK activated and proliferation or apoptosis of type II alveolar epithelial cells, levels of proliferation and apoptosis of AECII were measured by immunohistochemical assay of proliferating cell nuclear antigen (PCNA) and TUNEL method respectively.

RESULTSFAK and FAK-Tyr(397) activity of AECII on Matrigel-coated substrate increased: compared with air group, the expression of PCNA decreased and apoptotic index increased markedly in hyperoxia group (0.1498 ± 0.009 vs. 0.0953 ± 0.006, P < 0.05; 1.232 ± 0.6 vs. 13.40 ± 3.2, P < 0.01), but the expression of PCNA of AECII on Matrigel-coated substrate increased significantly (0.1498 ± 0.009 vs. 0.1921 ± 0.008, P < 0.01) and apoptotic index did not change. The expression of PCNA increased significantly (0.0953 ± 0.006 vs. 0.1125 ± 0.012, P < 0.05) and apoptotic index decreased markedly in hyperoxia + Matrigel group as compared with hyperoxia group (13.40 ± 3.2 vs. 7.641 ± 1.6, P < 0.05).

CONCLUSIONHyperoxia decreased the level of FAK and FAK-Tyr(397) in AECII, which may be a contributory mechanism of impaired proliferation and apoptosis of AECII in hyperoxia induced lung injury in premature rat. Matrigel could inhibit apoptosis and promote proliferation of AECII resulted from hyperoxia in vitro. Matrigel may play a protective role in hyperoxia-induced lung injury partly due to activated FAK.

Alveolar Epithelial Cells ; Animals ; Animals, Newborn ; Apoptosis ; Cell Proliferation ; Cells, Cultured ; Collagen ; pharmacology ; Drug Combinations ; Epithelial Cells ; drug effects ; enzymology ; Focal Adhesion Protein-Tyrosine Kinases ; metabolism ; Hyperoxia ; Laminin ; pharmacology ; Male ; Proteoglycans ; pharmacology ; Pulmonary Alveoli ; cytology ; enzymology ; pathology ; Rats ; Rats, Sprague-Dawley

Idiopathic pulmonary fibrosis (IPF) is a lethal parenchymal lung disease characterized by myofibroblast proliferation. Alveolar epithelial cells (AECs) are thought to produce myofibroblasts through the epithelial to mesenchymal transition (EMT). Receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin superfamily of cell surface receptors whose activation is associated with renal fibrosis during diabetes and liver fibrosis. RAGE is expressed at low basal levels in most adult tissues except the lung. In this study, we evaluated the interaction of ligand advanced glycation end products (AGE) with RAGE during the epithelial to myofibroblast transition in rat AECs. Our results indicate that AGE inhibited the TGF-beta-dependent alveolar EMT by increasing Smad7 expression, and that the effect was abolished by RAGE siRNA treatment. Thus, the induction of Smad7 by the AGE-RAGE interaction limits the development of pulmonary fibrosis by inhibiting TGF-beta-dependent signaling in AECs.
Animals ; Epithelial Cells/cytology ; Epithelial-Mesenchymal Transition/*drug effects ; Glycosylation End Products, Advanced/genetics/*metabolism ; Idiopathic Pulmonary Fibrosis/metabolism ; Pulmonary Alveoli/cytology ; RNA, Small Interfering/genetics ; Rats ; Receptors, Immunologic/genetics/*metabolism ; Smad7 Protein/genetics/*metabolism ; Transforming Growth Factor beta/genetics/metabolism