Stimulated Bronchial Epithelial Cells Release Bioactive Lysophosphatidylcholine 16:0, 18:0, and 18:1

PURPOSE: In human subjects and animal models with acute and chronic lung injury, the bioactive lysophosphatidylcholine (LPC) is elevated in lung lining fluids. The increased LPC can promote an inflammatory microenvironment resulting in lung injury. Furthermore, pathological lung conditions are associated with upregulated phospholipase A2 (PLA2), the predominant enzyme producing LPC in tissues by hydrolysis of phosphatidylcholine. However, the lung cell populations responsible for increases of LPC have yet to be systematically characterized. The goal was to investigate the LPC generation by bronchial epithelial cells in response to pathological mediators and determine the major LPC species produced. METHODS: Primary human bronchial epithelial cells (NHBE) were challenged by vascular endothelial growth factor (VEGF) for 1 or 6 h, and condition medium and cells collected for quantification of predominant LPC species by high performance liquid chromatography-tandem mass spectrometry (LC-MS-MS). The cells were analyzed by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) for PLA2. The direct effects of LPC in inducing inflammatory activities on NHBE were assessed by transepithelial resistance as well as expression of interleukin-8 (IL-8) and matrix metalloproteinase-1 (MMP-1). RESULTS: VEGF stimulation of NHBE for 1 or 6 h, significantly increased concentrations of LPC16:0, LPC18:0, and LPC18:1 in condition medium compared to control. The sPLA2-selective inhibitor (oleyloxyethyl phosphorylcholine) inhibited the VEGF-induced release of LPC16:0 and LPC18:1 and PLA2 activity. In contrast, NHBE stimulated with TNF did not induce LPC release. VEGF did not increase mRNA of PLA2 subtypes sPLA2-X, sPLA2-XIIa, cPLA2-IVa, and iPLA2-VI. Exogenous LPC treatment increased expression of IL-8 and MMP-1, and reduced the transepithelial resistance in NHBE. CONCLUSIONS: Our findings indicate that VEGF-stimulated bronchial epithelial cells are a key source of extracellular LPCs, which can function as an autocrine mediator with potential to induce airway epithelial inflammatory injury.

Evidence-based prevention (EBP): A review of cytochrome P450 expression in the bronchial epithelium and new approach to lung cancer prevention

The number of fatalities in Japan attributable to lung cancer exceeded 50000 in 2001. It is socially desirable that various markers, which can be utilized for the prevention of lung cancer, be established. We believe that smoking or exposure to carcinogens in air induces mutations in bronchial and alveolar epithelia, leading to the development of lung cancer. It would be useful to have markers of individual differences in susceptibility to chemical carcinogen-induced lung cancer 1) to identify genetic polymorphisms of enzymes metabolizing chemical carcinogens and 2) to investigate the expression of enzymes metabolizing chemical carcinogens. In this paper, we review CYP expression in the bronchial epithelium. CYP1, CYP2 and CYP3 are expressed in the bronchial epithelium. We also show the relationship between the genetic polymorphisms of cytochrome P450 (CYP) and a person's susceptibility to chemical carcinogen-induced lung cancer. We demonstrate the relationship between cigarette consumption and the CYP expression profile in the bronchial epithelium. To maintain and promote public health, we must apply evidence, such as CYP polymorphisms and CYP profiles to disease prevention and also to aggressively advance evidence-based prevention (EBP) of lung cancer.

Evidence-Based Prevention (EBP): A Review of Cytochrome P450 Expression in the Bronchial Epithelium and New Approach to Lung Cancer Prevention

The number of fatalities in Japan attributable to lung cancer exceeded 50000 in 2001. It is socially desirable that various markers, which can be utilized for the prevention of lung cancer, be established. We believe that smoking or exposure to carcinogens in air induces mutations in bronchial and alveolar epithelia, leading to the development of lung cancer. It would be useful to have markers of individual differences in susceptibility to chemical carcinogen-induced lung cancer 1) to identify genetic polymorphisms of enzymes metabolizing chemical carcinogens and 2) to investigate the expression of enzymes metabolizing chemical carcinogens. In this paper, we review CYP expression in the bronchial epithelium. CYP1, CYP2 and CYP3 are expressed in the bronchial epithelium. We also show the relationship between the genetic polymorphisms of cytochrome P450 (CYP) and a person’s susceptibility to chemical carcinogen-induced lung cancer. We demonstrate the relationship between cigarette consumption and the CYP expression profile in the bronchial epithelium. To maintain and promote public health, we must apply evidence, such as CYP polymorphisms and CYP profiles to disease prevention and also to aggressively advance evidence-based prevention (EBP) of lung cancer.

DYNAMIC ANALYSIS OF RHODAMINE 123 STAINING OF HUMAN BRONCHIAL EPITHELIUM DURING THE WOUND REPAIR PROCESS INDUCED BY FLUOROURACIL / 解剖学报

Objective To analyze the condition of Rhodamine 123 staining of human bronchial epithelium in vitro during the wound-repair process induced by fluorouracil(5-FU). Methods The bronchial epithelial cells in normal and 5-FU injurious group were obtained by enzymatic digestion and analyzed by flow cytometry.1.PI staining to identify the percentage of cells in different cell phase;2.Rhodamine 123 staining in live cells was to contrast the percentage of negative cells in two groups. Results 1.Analysis of cell cycle:apoptotic cells in injurious group increased,cells in S+G-2/M phase almost disappeared,majority of the remain live cells of injurious group were in G-0/G-1 phase;with the recover of bronchial epithelium,cells in S+G-2/M phase increased;2.The percentage of Rhodamine 123 negative staining live cells in injurious group was higher than that of normal group,and with the recover of bronchial epithelium,this percentage lowered to nearly normal.Conclusion 5-FU can make the cycling cells apoptosis and reserve quiescent phase cells.Among them there were bronchial stem cells which had the capacity to efflux Rhodamine 123.Just the proliferation and differentiation of these stem cells regenerated bronchial epithelium.Rhodamine 123 staining to sort the remain cells after 5-FU treatment by FACS can be used to enrich and purify bronchial stem cells.

Alteration of apoptotic susceptibility and bcl-2 gene in malignant transformation of human bronchial epithelial cells / 中国病理生理杂志

AIM: To demonstrate the susceptibility of cell apoptosis varies during the progress of cell malig- nant transformation from human being in vitro. METHODS: A SV40T - transfected human bronchial epithelial im- mortalized cell line (called M) was selected in this work, which has acquired some characteristics of malignant trans- formation at the later passage. The alterations of apoptosis and bcl- 2, P53 genes between early and later passage of M cells were investigated by means of TDT labeling in situ, chromosome FISH, RNA and protein testing, etc. RE- SULTS: Incidence of apoptosis induced by cis - platin was significantly lower in later than in early passages of M. Levels of bcl - 2 mRNA and protein in later passages were higher than early passages of M, and overxpression of bcl -2 was accumulated following the development of cellular malignancy. P53 protein level was as high in early as in later passages. CONCLUSION: Overexpression of bcl - 2 decreases the cellular sensitivity to apoptotic inductors plays an important role during progress of carcinogenesis in human bronchial epithelial cancers. The inactivation of P53 protein in the SV40 - T transfected M cell line may be one of reasons of bcl - 2 overexpression, but not associated with the accumulation of bcl - 2 expressed level during cell transformation.