Immune modulation of glycosaminoglycan derived from P. lewisi in TNF-α stimulated cells.

Poecilocoris lewisi (Korean name: "Kwangdaenolinjae") is a red-striped gold stink bug (insect) which has been used as a crude drug in traditional medicine of East Asia and Korea. In this study, ethanol extract and glycosaminoglycan from P. lewisi (Pl GAG), as an active substance among its components, were investigated for their potential anti-inflammatory actions. They were found to be a potent inducer of nitric oxide (NO) production from calf pulmonary artery endothelial (CPAE) cells and a stimulator of endothelial nitric oxide synthase in a dose-dependent manner. The anti-inflammatory activities were also evaluated by determining the level of adhesion molecules related to atherogenesis and pro-inflammatory cytokines, such as vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), secretory phospholipase A2, and prostaglandin E2, stimulated by tumor necrosis factor (TNF)-α in human umbilical vein endothelial cells (HUVEC). They also showed inhibitory effects on vascular endothelial growth factor (VEGF) production in HUVECs. Matrix metalloproteinases (MMP-2 and 9) were also inhibited by treatment with this extract or glycosaminoglycan. Furthermore, this GAG showed cytotoxicity against CT-26 colon cancer cells whereas having no cytotoxicity in CHO normal cells. Monosaccharide (amino, acidic, neutral monosaccharides) composition of used GAG was characterized by trimethylsilylated GC-MS analysis method.

Simvastatin inhibits cigarette smoking-induced emphysema and pulmonary hypertension in rat lungs.

RATIONALE: In cigarette smoking-induced chronic obstructive pulmonary disease, structural and functional derangements are characterized by parenchymal destruction and pulmonary hypertension. Statins are 3-hydroxy-3-methyl-glutaryl-coenzyme-A reductase inhibitors that have been used as lipid-lowering agents. These drugs also have additional pharmacologic properties, including antiinflammation, scavenging reactive oxygen species, restoring endothelial function, and antithrombogenesis, all of which can counteract the harmful effects of cigarette smoking. OBJECTIVE: We performed assays to determine whether simvastatin could attenuate lung damage induced by chronic cigarette smoking in rats. METHODS: In Sprague-Dawley rats exposed to cigarette smoke for 16 weeks, morphologic changes in the lungs and pulmonary arterial pressure were examined. MAIN RESULTS: Simvastatin inhibited lung parenchymal destruction and development of pulmonary hypertension, and also inhibited peribronchial and perivascular infiltration of inflammatory cells and induction of matrix metalloproteinase-9 activity in lung tissue. Simvastatin additionally prevented pulmonary vascular remodeling and the changes in endothelial nitric oxide synthase expression induced by smoking. In human lung microvascular endothelial cells, simvastatin increased expression of endothelial nitric oxide synthase mRNA. CONCLUSIONS: Simvastatin ameliorated the structural and functional derangements of the lungs caused by cigarette smoking, partly by suppressing inflammation and matrix metalloproteinase-9 induction and preventing pulmonary vascular abnormality. These findings indicate that statins may play a role in the treatment of cigarette smoking-induced chronic obstructive pulmonary disease.

Effect of hyperbaric oxygen on intercellular adhesion molecule-1 (ICAM-1) expression in murine lung.

BACKGROUND: The lung is one of the most susceptible organs to the toxic effect of high pressure oxygen. However, the contribution of the cellular adhesion molecules and inflammatory leukocytes in the pulmonary oxygen toxicity, especially in an acute exudative phase, is not well understood. In the present study we have investigated the toxic effect of hyperbaric oxygen (HBO) expressed by the analysis of the intercellular adhesion molecule-1 (ICAM-1) on the pulmonary vascular endothelial cells and leukocyte function. METHODS: Mice were exposed to HBO at 3 ATA of PO2 for 3, 4, or 6 h. Expression of ICAM-1 was serially observed by immunohistochemical analysis. The oxidative metabolic activity of the leukocytes was measured after HBO exposure. RESULTS: After HBO exposure an increase in the number of pulmonary interstitial leukocytes (PIL) and bronchoalveolar lavage (BAL) was observed at 72 h and 48 h, respectively. The expression of ICAM-1 was strongly enhanced immediately after HBO exposure and this enhancement lasted for 24 h. This suggests the importance of enhanced expression of adhesion molecules in the generation of pulmonary oxygen toxicity. However, we could not detect increased chemiluminescence activity in the early phase in the BAL cells and PIL. CONCLUSION: Expression of ICAM-1 was enhanced from the very early stage after HBO, but neither accumulation of leukocytes in the lung nor increase in the chemiluminescence activity were observed in this phase. Therefore, activation of inflammatory leukocytes in the pulmonary oxygen toxicity may occur only after prolonged (more than 4 h) or repetitive exposures to HBO.

Regulation of rat pulmonary endothelial cell interleukin-6 production by bleomycin: effects of cellular fatty acid composition.

Previous studies have shown upregulation of lung cell interleukin-6 (IL-6) production in bleomycin-induced pulmonary fibrosis. To further elucidate the regulatory mechanisms governing this disease, the effects of bleomycin on the production of the pleiotropic cytokine, IL-6, were investigated in lung endothelial cells. Rat pulmonary artery endothelial cells were treated with bleomycin at doses previously shown to be effective in upregulating cytokine production in these cells, and the conditioned media was collected and assayed for IL-6 activity. The results show that these endothelial cells constitutively produced IL-6 and that bleomycin increased the production in a time- and dose-dependent manner. Feeding rats diets deficient in n-6 fatty acids is known to ameliorate bleomycin-induced lung fibrosis. In order to examine if fatty acids could modulate IL-6 production in vitro, cells were lipid depleted and then supplemented with 18:1n-9, 18:2n-6, or 18:3n-3 fatty acids, and the effects of bleomycin on IL-6 production reexamined. This regimen resulted in significant depletion of arachidonate in the 18:1n-9 and 18:3n-3 supplemented cells, which was associated with significantly reduced IL-6 production relative to the 18:2n-6-supplemented cells, both constitutively and when stimulated with bleomycin. Preincubation with indomethacin did not significantly inhibit the production of IL-6 by all three groups of cells, nor did supplementation with a stable prostacyclin analog increase IL-6 production. These results suggest that endothelial cell IL-6 production is not directly dependent on prostacyclin or other cyclooxygenase metabolites but may require or be upregulated by 18:2n-6 and/or metabolites derived from it.(ABSTRACT TRUNCATED AT 250 WORDS)

Studies of myofibrillar ATPase in ragweed-sensitized canine pulmonary smooth muscle.

The maximal shortening velocities of tracheal and pulmonary vascular smooth muscle from ragweed-sensitized dogs were significantly higher than those of muscles from their littermate controls. Myofibrils of tracheal and pulmonary vascular smooth muscle from ragweed-sensitized and control dogs were obtained with use of Triton X-100 homogenizing solution. The myofibrillar adenosinetriphosphatase (ATPase) activities of the sensitized tissues were significantly higher (P less than 0.05) than those of their respective controls.