Pulmonary lipid phosphate phosphohydrolase in plasma membrane signalling platforms

2001 ◽  
Vol 358 (3) ◽  
pp. 637-646 ◽  
Author(s):  
Meera NANJUNDAN ◽  
Fred POSSMAYER
Keyword(s):  
Cell Lines ◽  
Lung Tissue ◽  
Type Ii Cells ◽  
Type Ii ◽  
Rat Lung ◽  
Caveolin 1 ◽  
Type Ii Cell ◽  
Lipid Phosphate ◽  
Lipid Phosphate Phosphohydrolase ◽  
Isolated Rat

Lipid phosphate phosphohydrolase (LPP) has recently been proposed to have roles in signal transduction, acting sequentially to phospholipase D (PLD) and in attenuating the effects of phospholipid growth factors on cellular proliferation. In this study, LPP activity is reported to be enriched in lipid-rich signalling platforms isolated from rat lung tissue, isolated rat type II cells and type II cell-mouse lung epithelial cell lines (MLE12 and MLE15). Lung and cell line caveolin-enriched domains (CEDs), prepared on the basis of their detergent-insolubility in Triton X-100, contain caveolin-1 and protein kinase C isoforms. The LPP3 isoform was predominantly localized to rat lung CEDs. These lipid-rich domains, including those from isolated rat type II cells, were enriched both in phosphatidylcholine plus sphingomyelin (PC+SM) and cholesterol. Saponin treatment of MLE15 cells shifted the LPP activity, cholesterol, PC+SM and caveolin-1 from lipid microdomains to detergent-soluble fractions. Elevated LPP activity and LPP1/1a protein are present in caveolae from MLE15 cells prepared using the cationic-colloidal-silica method. In contrast, total plasma membranes had a higher abundance of LPP1/1a protein with low LPP activity. Phorbol ester treatment caused a 3.8-fold increase in LPP specific activity in MLE12 CEDs. Thus the activated form of LPP1/1a may be recruited into caveolae/rafts. Transdifferentiation of type II cells into a type I-like cell demonstrated enrichment in caveolin-1 levels and LPP activity. These results indicate that LPP is localized in caveolae and/or rafts in lung tissue, isolated type II cells and type II cell lines and is consistent with a role for LPP in both caveolae/raft signalling and caveolar dynamics.

Control of release of surfactant phospholipids in the isolated perfused rat lung

1981 ◽  
Vol 51 (1) ◽  
pp. 90-98 ◽  
Author(s):  
T. E. Nicholas ◽  
H. A. Barr
Keyword(s):  
Tidal Volume ◽  
Type Ii ◽  
Rat Lung ◽  
Cyclic Monophosphate ◽  
Type Ii Cell ◽  
Surfactant Phospholipids ◽  
Isolated Rat Lung ◽  
Isolated Rat

We used the isolated rat lung to investigate surfactant release. The lung was ventilated at 60.min-1 with 5% CO2–95% O2 and perfused at 10 ml.min-1 with Krebs-bicarbonate (4.5% albumin). After 20 min during which antagonist drugs were present, the lungs were either hyperventilated or agonist drugs were added. After another 15 min lungs were lavaged. Peak inspired pressures (PIP) in excess of 12 cmH2O produced progressively greater phospholipid (PL) yields. Whereas ventilating with PIP of 9 cmH2O and end-expired pressure(EEP) of 5 cmH2O produced 5.9 +/- 0.8 (mean +/-SD) (n = 17) mg PL. g dry lung-1, ventilating with PIP of 20 cmH2O and EEP of 0 cmH2O produced 10.1 +/- 1.3 (n = 26). PL release was unaffected by tetrodotoxin, propranolol, atropine, cyproheptadine, or indomethacin. PL was increased by salbutamol and dibutyryl adenosine 3',5'-cyclic monophosphate but not by pilocarpine or dibutyryl guanosine 3',5'-cyclic monophosphate. We conclude, that increasing tidal volume immediately releases surfactant, probably by distorting the type II cell and elevating cAMP. An intrapulmonary neural reflex is not involved in this response of the isolated rat lung, nor is histamine, 5-hydroxytryptamine, or a prostaglandin.

scholarly journals Phospholipid-transfer activities in cytosols from lung, isolated alveolar type II cells and alveolar type II cell-derived adenomas

1983 ◽  
Vol 215 (3) ◽  
pp. 637-642 ◽  
Author(s):  
G L Pool ◽  
D G Bubacz ◽  
R H Lumb ◽  
R J Mason
Keyword(s):  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Alveolar Type Ii Cells ◽  
Transfer Protein ◽  
Alveolar Type Ii Cell ◽  
Phospholipid Transfer ◽  
Type Ii Cell ◽  
Specific Proteins ◽  
Isolated Rat

We have examined phospholipid-transfer activities in cytosols from rat and mouse whole lung, isolated rat alveolar type II cells and alveolar type II cell-derived mouse pulmonary adenomas. We report an enrichment in phosphatidylcholine and phosphatidylglycerol (but not phosphatidylinositol) protein-catalysed transfer in the type II cell and adenoma cytosols compared with the whole-lung cytosols. The activities from these cytosols were resolved using column chromatofocusing, which clearly demonstrated the presence of a phosphatidylcholine-specific transfer protein in each of the four tissues. In addition, two proteins (rat) or three proteins (mouse) catalysing both phosphatidylcholine and phosphatidylglycerol transfer were resolved from whole lung, whereas in both the rat isolated alveolar type II cells and the mouse type II cell-derived adenomas one of these less specific proteins is not present.

Derivation of tumorigenic and non-tumorigenic mouse alveolar type-II cell lines from fetal type-II cells after a combinedin vivo/in vitro carcinogen treatment

1992 ◽  
Vol 52 (2) ◽  
pp. 290-297 ◽  
Author(s):  
L. C. J. M. Oomen ◽  
J. Calafat ◽  
A. A. W. Ten Have-Opbroek ◽  
J. Egberts ◽  
P. Demant
Keyword(s):  
Cell Lines ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Alveolar Type Ii Cell ◽  
Type Ii Cell

An Ultrastructural Comparison of Rat Lung Cells Grown in an Organotypic Culture System with Lung Tissue Found in the Whole Animal

1976 ◽  
Vol 34 ◽  
pp. 172-173
Author(s):  
Peter J. Del Vecchio ◽  
Edward P. Dougherty ◽  
William H. J. Douglas
Keyword(s):  
Lung Tissue ◽  
Organotypic Culture ◽  
Fetal Lung ◽  
Lung Cells ◽  
Type Ii Cells ◽  
Type Ii ◽  
Rat Lung ◽  
Tissue Organization ◽  
Fetal Rat ◽  
Fetal Rat Lung

This study describes the ultrastructure of an organotypic system prepared from rat fetal lung and compares it to lung in rat fetuses. The preparation of the organotypic system has been described elsewhere (1).The organotypic systems in this study are prepared from 18-19 day fetal rat lung and spend two days in culture making the cells a total of 20-21 days old. The fine structure of the type II cells present in this system will be compared to the type II cells in fetal lung at 20-21 days gestation. Because the tissue organization of the organotypic system is more like the organization of fetal lung at an earlier stage (18-19 days gestation) , the cell to cell relationships of the organotypic system are compared to fetal lung tissue at this stage.The histology of the organotypic system is similar to that of the fetal lung in its glandular stage (Fig. 1). The epithelial cells are all columnar and are surrounded by relatively undifferentiated mesenchyme.

Generation and characterization of monoclonal antibodies to alveolar type II cell lamellar body membrane

1998 ◽  
Vol 275 (1) ◽  
pp. L172-L183 ◽  
Author(s):  
K. Zen ◽  
K. Notarfrancesco ◽  
V. Oorschot ◽  
J. W. Slot ◽  
A. B. Fisher ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Membrane Protein ◽  
Lamellar Body ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Rat Lung ◽  
Lamellar Bodies ◽  
Alveolar Type Ii Cell ◽  
Type Ii Cell

Monoclonal antibodies against the limiting membrane of alveolar type II cell lamellar bodies were obtained after immunization of mice with a membrane fraction prepared from lamellar bodies isolated from rat lungs. The specificity of the antibodies was investigated with Western blot analysis, indirect immunofluorescence, and electron-microscopic immunogold studies of freshly isolated or cultured alveolar type II cells, alveolar macrophages, and rat lung tissue. One of the monoclonal antibodies identified, MAb 3C9, recognized a 180-kDa lamellar body membrane (lbm180) protein. Immunogold labeling of rat lung tissue with MAb 3C9 demonstrated that lbm180 protein is primarily localized at the lamellar body limiting membrane and is not found in the lamellar body contents. Most multivesicular bodies of type II cells were also labeled, as were some small cytoplasmic vesicles. Golgi complex labeling and plasma membrane labeling were weak. The appearance of lbm180 protein by immunofluorescence in fetal rat lung cryosections correlated with the biogenesis of lamellar bodies. The lbm180 protein decreased with time in type II cells cultured on plastic. The lbm180 protein is an integral membrane protein of lamellar bodies and was also found in the pancreas and the pancreatic βHC9 cell line but not in the rat brain, liver, kidney, stomach, or intestine. The present study provides evidence that the lbm180 protein is a lung lamellar body and/or multivesicular body membrane protein and that its antibody, MAb 3C9, will be a valuable reagent in further investigations of the biogenesis and trafficking of type II cell organelles.

Phosphatidate phosphohydrolase activity as a marker for surfactant synthesis in organotypic cultures of type II alveolar pneumonocytes

1983 ◽  
Vol 60 (1) ◽  
pp. 199-207
Author(s):  
W.H. Douglas ◽  
S.K. Sommers-Smith ◽  
J.M. Johnston
Keyword(s):  
Pulmonary Surfactant ◽  
Specific Activity ◽  
Type Ii Cells ◽  
Type Ii ◽  
Rat Lung ◽  
Organotypic Cultures ◽  
Foetal Rat ◽  
Phosphatidate Phosphohydrolase ◽  
Type Ii Cell ◽  
Specific Activities

The specific activity of phosphatidate phosphohydrolase (PAPase) (EC 3.1.3.4) has been assayed in organotypic cultures of foetal rat lung type II alveolar pneumonocytes and in L2 cells derived from type II cells of the adult rat lung. This enzyme catalyses a critical step in the synthesis of phosphatidylcholine, the major lipid component of pulmonary surfactant. Surfactant is produced by the mature type II cell in culture as well as in vivo. The specific activity of PAPase in organotypic cultures prepared from foetal rat lung starting at 16 days of gestation increased four- to fivefold during the first 7 days in culture. The specific activity of this enzyme was further increased through the 21 days of culture. In parallel with the increase in PAPase specific activity in the cultures were morphological changes in the type II cells such as the appearance of increased numbers of lamellar bodies. The specific activities of PAPase samples derived from non-type II cell cultures maintained under identical conditions were compared. Organotypic cultures and L2 cells, a culture system that also exhibits type II cell characteristics, show PAPase specific activities five to six times greater than cultures that do not contain type II cells. PAPase activity in the type II cell cultures parallels the development of mature patterns of pulmonary surfactant synthesis storage and secretion.

Changes in gamma-glutamyltransferase activity in rat lung tissue, BAL, and type II cells after hyperoxia

1997 ◽  
Vol 273 (3) ◽  
pp. L537-L547 ◽  
Author(s):  
R. J. Van Klaveren ◽  
D. Dinsdale ◽  
J. L. Pype ◽  
M. Demedts ◽  
B. Nemery
Keyword(s):  
Lung Tissue ◽  
Active Role ◽  
Exposed Group ◽  
Type Ii Cells ◽  
Strongly Correlated ◽  
Type Ii ◽  
Gamma Glutamyltransferase ◽  
Male Wistar Rats ◽  
Type Ii Cell ◽  
Precursor Molecules

The effect of hyperoxia on gamma-glutamyltransferase (gamma-GT), an important enzyme for the uptake of precursor molecules for intracellular synthesis of glutathione (GSH), has not been established. Our aim was to investigate the effects of prolonged subtoxic levels of hyperoxia on gamma-GT activity and GSH levels in lung tissue, epithelial lining fluid (ELF), and isolated rat type II cells immediately after their isolation and 48 h later when kept in culture in normoxia. Seventeen male Wistar rats were divided in three groups (n = 5-7) and were exposed to air or to 60 or 85% O2 for 7 days. Pulmonary gamma-GT activity increased in the 60 and 85% O2-exposed animals (1.6- and 3.2-fold, respectively), and tissue GSH levels increased only in the 60% O2 group (1.3-fold). In isolated type II cells from 60 and 85% O2-exposed animals, gamma-GT activity decreased by -70 and -88%, respectively, which was supported by cytochemical staining. Type II cell gamma-GT mRNA expression tended only to decrease after 85% O2. Type II cell gamma-GT activity strongly correlated with ELF gamma-GT (r = 0.60, P < 0.001), and ELF gamma-GT strongly correlated with ELF GSH (r = 0.75, P < 0.0001). When in culture, type II cell gamma-GT activity and GSH levels remained, respectively, 2.5- and 1.9-fold lower in the 60% O2-exposed group, but, in the 85% O2-exposed group, gamma-GT activity increased 2.1-fold, and GSH levels dropped to the levels of the control cells. Hyperoxia led to a concentration-dependent decrease in gamma-GT activity in rat type II cells, possibly by direct inactivation, but led to an increase in whole lung tissue gamma-GT. There seemed to be a negative feedback between intracellular GSH levels and type II cell gamma-GT activity. gamma-GT levels in the ELF were correlated with type II cell gamma-GT activity, but ELF gamma-GT did not seem to play an active role in the regulation of the ELF GSH pool. Hyperoxia decreased ELF GSH levels, possibly by increased degradation of GSH in the parenchymal lung tissue as a result of the increased gamma-GT activity.

Glutathione transport by type II cells in perfused rat lung

1994 ◽  
Vol 267 (4) ◽  
pp. L447-L455 ◽  
Author(s):  
C. Bai ◽  
L. A. Brown ◽  
D. P. Jones
Keyword(s):  
Fluorescence Microscopy ◽  
High Performance ◽  
Cell Types ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Uptake System ◽  
Type Ii ◽  
Rat Lung ◽  
Perfused Lung ◽  
Type Ii Cell

Glutathione (GSH) is an antioxidant that protects the lung against oxidative-injury. Most cells rely on synthesis of GSH to maintain intracellular supply and only a few cell types take up intact GSH. Although isolated type II cells from rat have a Na(+)-dependent uptake system that transports GSH into the cells against a concentration gradient, it is not known whether this occurs from the vasculature in the intact lung or whether other cell types in the lung also transport GSH. Based on the knowledge that gamma-glutamyl analogues of GSH are also transported by the Na(+)-GSH transporter, a method was developed and used to study the cell specificity of GSH uptake in perfused lung. A stable, fluorescent GSH S-conjugate (GSH-I14) was synthesized and separated from the original dye as analyzed by high-performance liquid chromatography. Studies with isolated alveolar type II cells showed that uptake of GSH-I14 was Na+ dependent and inhibited by GSH. In addition, uptake of GSH by the type II cells was inhibited by GSH-I14. After perfusion of the isolated rat lung with GSH-I14, the conjugate accumulated primarily in the alveolar type II cell as observed by fluorescence microscopy. This was confirmed by isolation of type II cells and measurement of GSH-I14 content. Thus these results show that specificity of GSH transport can be studied with the fluorescent derivative, GSH-I14, and that in the isolated perfused lung type II cells can transport and concentrate GSH-I14 from the perfusate. Quantitative fluorescence microscopy will be required to further determine relative transport activities by other cell types.

P2u purinoceptor stimulation of surfactant secretion coupled to phosphatidylcholine hydrolysis in type II cells

1994 ◽  
Vol 267 (5) ◽  
pp. L625-L633 ◽  
Author(s):  
L. I. Gobran ◽  
Z. X. Xu ◽  
Z. Lu ◽  
S. A. Rooney
Keyword(s):  
Phospholipase D ◽  
Receptor Gene ◽  
Primary Cultures ◽  
Cell Receptor ◽  
Northern Analysis ◽  
Type Ii Cells ◽  
Type Ii ◽  
Type Ii Cell ◽  
Subsequent Activation ◽  
Phosphatidylcholine Secretion

ATP is known to stimulate surfactant phospholipid secretion in type II cells, and there is evidence that this effect is mediated by a P2 purinoceptor. At least five subtypes of the P2 receptor have been reported, but it is not clear which one exists on the type II cell. To determine whether it is the P2u subtype, at which UTP is equipotent with ATP, we have compared the effects of ATP and UTP on phosphatidylcholine secretion and second messenger formation in primary cultures of rat type II cells. ATP and UTP were equally potent in stimulating phosphatidylcholine secretion and phospholipase D activation. The potency order, UTP = ATP > ADP > 2-methylthio-ATP, was the same as that reported for the P2u receptor. UTP stimulated diacylglycerol and phosphatidic acid formation to the same extent as ATP. ATP also increased choline formation. Formation of diacylglycerol was biphasic, and the first peak in response to ATP was previously shown to be associated with inositol trisphosphate formation. Northern analysis showed that the P2u receptor gene was expressed to a greater extent in type II cells than in whole lung. These data suggest that ATP and UTP act via a P2u receptor that is coupled to phosphoinositide-specific phospholipase C with subsequent activation of phospholipase D acting on phosphatidylcholine. ATP has also been reported to act at an additional type II cell receptor coupled to adenylate cyclase. In contrast, UTP did not promote adenosine 3',5'-cyclic monophosphate formation and therefore does not act at that receptor.

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