• Tuberculosis and Respiratory Diseases
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• v.44 no.5
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• pp.1114-1124
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• 1997

Background : Endothelin(ET) is a very potent vasoconstrictive peptide produced by endothelial cells of pulmonary artery. The endothelin level was increased in plasma of primary pulmonary hypertension and acute pulmonary thromboembolism and it was suggested that the endothelin might do a critical role in the cardiopulmonary dysfunction in these two conditions. But the exact mechanism of increase of ET has not been known. In these two conditions, platelet activation and thrombosis are the main pathophysiologic findings. So there is a possibility that the platelet might stimulate endothelin secretion from endothelial cells. Therefore, we performed this study to evaluate the role of platelet and its mediators on endothelin production in bovine pulmonary artery endothelial(BPAE) cells. Method : Bovine pulmonary artery endothelial cells, ATCC certified cell line 209, were cultured and treated with human platelets($10^6{\sim}10^8/ml$), thrombin (0.1~10u/ml), TGF-${\beta}1$(1~100uM), serotonin(1~100uM), and endotoxin(1ug/ml) in a final volume of 500ul for 18 hours. Levels of ir(immunoreactive)-ET in each conditioned medium were measured by a radioimmunoassay specific for ET. Result : The increase of ir-ET levels was platelet number and time dependent over 18 hours. When washed human platelets were added($10^8/ml$), the ir-ET levels were significantly higher than that of control(p<0.05) at 8 and 18 hours after culture. Subthreshold concentration of platelets($10^7/ml$) coincubated with endotoxin(1ug/ml) or subthreshold dose of thrombin(0.1u/ml) stimulated ir-ET secretion from BPAE cells significantly(p<0.05) compared with control. Thrombin(1ug/ml, 10ug/ml) and TGF-${\beta}1$(100pM, 1000pM) significantly increased ir-ET secretion from BP AE cells(p<0.05) compared with control, but serotoin(1~100uM) and endotoxin(1ug/ml) did not stimulate the ir-ET secretion. Conclusions : Platelets stimulate endothelin secretion from bovine pulmonary artery endothelial cells. The mechanism of increase of endothelin secretion seems to be a stimulation by platelet itself or by mediators, such as TGF-${\beta}1$, secreted from activated platelets. And, in this study, the priming effect of platelets on endothelin secretion from BPAE cells could be another possibility.

• Tuberculosis and Respiratory Diseases
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• v.81 no.2
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• pp.132-137
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• 2018

Background: The pathophysiology of chronic obstructive pulmonary disease (COPD) includes inflammation, oxidative stress, an imbalance of proteases and antiproteases and apoptosis which has been focused on lately. Abnormal apoptotic events have been demonstrated in both epithelial and endothelial cells, as well as in inflammatory cells including neutrophils and lymphocytes in the lungs of COPD patients. An increased propensity of activated T lymphocytes to undergo apoptosis has been observed in the peripheral blood of COPD patients. Therefore, the apoptosis of T lymphocytes without activating them was investigated in this study. Methods: Twelve control subjects, 21 stable COPD patients and 15 exacerbated COPD patients were recruited in the study. The T lymphocytes were isolated from the peripheral blood using magnetically activated cell sorting. Apoptosis of the T lymphocytes was assessed with flow cytometry using Annexin V and 7-aminoactinomycin D. Apoptosis of T lymphocytes at 24 hours after the cell culture was measured so that the T lymphocyte apoptosis among the control and the COPD patients could be compared. Results: Stable COPD patients had increased rates of $CD4^+$ T lymphocyte apoptosis at 24 hours after the cell culture, more than the $CD4^+$ T lymphocyte apoptosis which appeared in the control group, while the COPD patients with acute exacerbation had an amplified response of $CD4^+$ T lymphocyte apoptosis as well as of $CD8^+$ T lymphocyte apoptosis at 24 hours after the cell culture. Conclusion: Stable COPD patients have more apoptosis of $CD4^+$ T lymphocytes, which can be associated with the pathophysiology of COPD in stable conditions.

• Tuberculosis and Respiratory Diseases
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• v.41 no.4
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• pp.319-327
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• 1994

Background: The pathogenetic mechanism of adult respiratory distress syndrome(ARDS) is not clearly defined yet, but it is well known that increased pulmonary capillary permeabilty is characteristic feature of ARDS. The increased alveolar-capillary permeability is usually preceded by damage of pulmonary artery endothelial cells. The released enzymes and oxygen free radicals from the activated neutrophils seem to play a predominant role in endothelial cell cytotoxicity. The activated neutrophils, however, probably are not the sole contributing factor in this type of damage because many cases of ARDS have been reported in severe neutropenia. Bacterial endotoxin perse and/or oxygen free radicals released from endothelial cells are suggested to be possible factors that contribute to the development of ARDS. The purpose of this study is to investigate the direct cytotoxicity of endotoxin and the role of oxygen free radicals released from the endothelial cells in endotoxin-induced endothelial cell cytotoxicity. Methods: First, to investigate whether endotoxin is cytotoxic to HUVE by itself, various doses of endotoxin were added to culture medium and cytotoxicity was measured. Second, to evaluate the possible role of oxygen free radical in endotoxin-induced HUVE cytotoxicity, various antioxidants were added on the endotoxin-induced HUVE cytotoxicity and cytotoxicity was measured. Third, to verify the release of oxygen free radicals from HUVE, the concentrations of hydrogen peroxide in the endotoxin-treated culture supernatant were measured. Finally, to observe the cytotoxic effect of hydrogen peroxide, HUVE cytotoxicity in the presence of various doses of hydrogen peroxide was measured. The fourth generations of subcultured HUVE from primary culture were used. The cell cytotoxicity was quantified by the chromium-51 release assay. Results: 1) Endotoxin alone showed HUVE cytotoxicity in a dose-dependent fashion. 2) Endotoxin-induced HUVE cytotoxicity was significantly attenuated by the pretreatment of catalase and DMTU. 3) Hydrogen peroxide was released from HUVE after endotoxin treatment in a dose-dependent fashion. 4) Exogenous hydrogen peroxide also showed HUVE cytotoxicity in a dose-dependent fashion. Conclusion: These results suggest that endotoxin alone can directly injure HUVE, and, oxygen-free radicals released from HUVE in response to endotoxin may also participate in the endotoxin-induced HUVE cytotoxicity.

• BMB Reports
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• v.37 no.2
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• pp.239-245
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• 2004

We have previously demonstrated that the redox reactant pyruvate prevents apoptosis in the oxidant model of bovine pulmonary artery endothelial cells (BPAEC), and that the anti-apoptotic mechanism of pyruvate is mediated in part via the mitochondrial matrix compartment. However, cytosolic mechanisms for the cytoprotective feature of pyruvate remain to be elucidated. This study investigated the pyruvate protection against endothelial cytotoxicity when the glycolysis inhibitor 2-deoxy-D-glucose (2DG) was applied to BPAEC. Millimolar 2DG blocked the cellular glucose uptake in a concentration- and time-dependent manner with >85% inhibition at $\geq$5 mM within 24 h. The addition of 2DG evoked BPAEC cytotoxicity with a substantial increase in lipid peroxidation and a marked decrease in intracellular total glutathione. Exogenous pyruvate partially prevented the 2DG-induced cell damage with increasing viability of BPAEC by 25-30%, and the total glutathione was also modestly increased. In contrast, 10 mM L-lactate, as a cytosolic reductant, had no effect on the cytotoxicity and lipid peroxidation that are evoked by 2DG. These results suggest that 2DG toxicity may be a consequence of the diminished potential of glutathione antioxidant, which was partially restored by exogenous pyruvate but not L-lactate. Therefore, pyruvate qualifies as a cytoprotective agent for strategies that attenuate the metabolic dysfunction of the endothelium, and cellular glucose oxidation is required for the functioning of the cytosolic glutathione/NADPH redox system.

• KSBB Journal
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• v.18 no.1
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• pp.25-29
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• 2003

In this study, we examined the effects of the methanolic extract(CL-ex) of Codonopsis lanceolata on the angiogenesis stimulated with basic fibroblast growth factor(bFGF) in vitro, using porcine pulmonary arterial endothelial cells(PPAECs). In addition, we investigated the endothelial functions involved in angiogenesis, such as proliferation, migration and secretion of matrix metalloproteinases(MMPs), using human umbilical vein endothelial cells(HUVECS). CL-ex inhibited FGF-induced sprout formation in vitro at concentrations of 0.1-100 ug/ml. Although CL-ex did not affect the proliferation of endothelial cells, CL-ex strongly inhibited the FGF-induced migration of HUVECS at concentrations of 0.1-1 ug/ml; the degree of inhibition of endothelial cells by C-ex was 49.4% at 0.1 ug/ml and 71.9 % at 1.0 ug/ml. Moreover, CL-ex inhibited the secretion of MMPs from HUVECS stimulated with FGF. Therefore, the inhibitory effect of CL-ex on angiogenesis in vitro could be explained by the inhibition of endothelial cell migration. From these results, we suggest that Codonopsis lanceolata is a useful herb for the development of therapeutics or preventive food factors for angiogenesis related diseases, such as tumors.

• YAKHAK HOEJI
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• v.43 no.4
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• pp.487-493
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• 1999

Effects of Ginkgo biloba extract (EGb 761) on the anti-pulmonary hypertensive action of enalapril were evaluated in rats. Pulmonary hypertension was induced by monocrotaline treatment (60mg/kg, i.p.) in normotensive rats. In the systolic pulmonary artery pressure, the control group was 33$\pm$2 mmHg, comparing to the normal group of 19$\pm$1 mmHg. That of enalapril group(20mg/kg/day, p.o.) was 26$\pm$2 mmHg. In the isolated lung preparation, acetylcholine, which was endothelium dependent vasodilator, induced the decrease of pulmonary artery perfusion pressure(-2.0$\pm$0.7 mmHg) in normal group, but the increase of that of 3.4$\pm$0.6 and 3.0$\pm$0.9 mmHg in control and enalapril group, respectively. And that of the combined group was -0.5$\pm$0.2 mmHg. In the isolated pulmonary artery, acetylcholine(10-5M) induced the relaxation of 65$\pm$6% in normal group, but 15 and 8% in control and enalapril group, respectively. And that of the combined group was resulted 55$\pm$2%. These results suggested that co-administration of Ginkgo biloba extract(EGb 761) potentiated the anti-pulmonary hypertensive effects of enalapril through the increase of pulmonary vasodilation due to the protection of endothelial cell by antioxidant action of Ginkgo biloba extract (EGb 761).

• The Korean Journal of Pharmacology
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• v.29 no.2
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• pp.213-223
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• 1993

To investigate the endothelium dependent vascular reactivity of the systemic arterial and the pulmonary arterial system in acute renal hypertensive rats of 2-kidney, 1-ligation type (RHRs), acetylcholine (ACh)-induced vasodilation and depressor effects were evaluated in isolated arteries and in vivo, respectively, in the presence and absence of functional endothelium. ACh $(10^{-5}\;M)$ relaxed the intact thoracic aortas from RHRs and normotensive rats (NRs), but the effect was significantly smaller for those from RHRs (34 and 86%, respectively, p<0.01). ACh-induced vasodilation was completely abolished after removal of endothelial cell or pretreatment with EDRF inhibitors, L-NAME and MB, indicative of its dependence on intact endothelial or EDRF function. ACh also induced vasorelaxation of the intact pulmonary arteries from RHRs and NRs; however, unlike the effects on the thorcic aorta, no significant difference in amplitude was noted between two groups. ACh $(0.1{\sim}10\;{\mu}g/kg,\;i.v.)$ reduced mean systemic arterial pressure in anesthetized RHRs and in NRs to the similar magnitude (% change: 39 and 46% at $10\;{\mu}g/kg$, respectively) and these hypotensive effects were significantly decreased after pretreatment with L-NAME (30 mg/kg, i.v.). Deprssor effects of ACh on mean pulmonary arterial pressure were similar in RHRs and NRs with and without pretreatment of L-NAME. However, in both NRs and RHRs, the depressor effects of ACh on mean pulmonary arterial pressure were significantly reduced compared with those for mean systemic arterial pressure, and the increment of mean pulmonary arterial pressure noted after L-NAME $(0.1{\mu}100\;mg/kg,\;i.v.)$ was significantly smaller than that for mean systemic arterial pressure. These results indicate that in RHRs the endothelial cell function was impaired, at least in part, in systemic arterial system, but not in pulmonary arterial system, and both ACh-evoked and basal release of EDRF was less in the pulmonary arterial system than in systemic arterial system of both NRs and RHRs.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.50-54
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• 2003

Polygonum cuspidatum has been used as a fork medicine for a long time. Emodin was purified from the root of P. cuspidatum by thin layer chromatography (TLC) and preparative high perfomance liquid chromatography (HPLC). The effects of emodin on the migration of endothelial cells and in vitro angiogenesis stimulated with vascular endothelial cell growth factor (VEGF) were examined, using human umbilical vein endothelial cells (HUVECs) and porcine pulmonary arterial endothelial cells (PPAECs). Emodin potently inhibited the VEGF-induced migration of (HUVECs) at relatively low cocentrations $(0.1-10\;{\mu}g/ml)$; the inhibition of endothelial cells by emodin was 75.4% at $0.1\;{\mu}g/ml$ and about 90% at $1\;{\mu}g/ml$. Emodin also inhibited VEGF-induced sprout formation in vitro at concentrations of $0.1-10\;{\mu}g/ml$. Emodin was also evaluated for the inhibitory potential on in vivo angiogenesis in a growing chick embryo chorioallantoic membranes (CAM). At a concentration of $1.0\;{\mu}g/ml$ Per disc, emodin was able to induce avacular zone in the CAMs. These findings suggest that emodin is a potent angiogenesis inhibitor and P. cuspidatum is a useful herb in the development of therapeutics for angiogenesis dependent diseases.

• Journal of Chest Surgery
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• v.37 no.12
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• pp.1025-1028
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• 2004

Epithelioid hemangioendothelioma (HE) is a very rare malignant tumor that is pathologically benign tumor originating from endothelial cell but clinically presents metastasis and recurrence. A 29-year-old asymptomatic man, preoperatively diagnosed as lung cancer in the left lower lung, underwent a lobectomy, a wedge lung resection of left upper lung, and partial resection of diaphragm. Left lower lobar lesion was confirmed as pulmonary epithelioid hemangioendothelioma, but the lesions of the left upper lung and diaphragm were remained calcified by spontaneous regression of HE. We report a case of subcutaneous metastasis that occurred two times at 10 months and 19 months after previous surgical treatment of pulmonary EH.

• Tuberculosis and Respiratory Diseases
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• v.47 no.2
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• pp.150-160
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• 1999

Background: The CREST syndrome is an indolent form of progressive systemic sclerosis. Although its clinical progress is indolent, pulmonary hypertension(PH) associated with CREST syndrome have grave prognosis with over 40 percent mortality rate at 2 year follow-up. But the pathogenesis of pulmonary hypertension in this disease is not known, and classified as either primary or secondary PH. Clonality of endothelial cell proliferation in plexiform lesion is a molecular marker which allows distinction between primary and secondary PH. We performed this study to know whether the PH associated with CREST syndrome is a variant of primary PH or is a secondary PH. Methods: We assessed the X-chromosome inactivation based on the methylation pattern of the human androgen-receptor gene by PCR(HUMARA). Endothelial cells in plexiform lesions from female patients(n=3) with PH associated with CREST syndrome were microdissected from paraffin blocks. Vascular smooth muscle cells and lung parenchyma were also microdissected for clonality studies. Results: The proliferating endothelial cells in 14 plexiform lesions were all polyclonal. Similarly proliferated smooth muscle cells from 5 vessels with medial hypertrophy were also polyclonal. Conclusion: These results suggest that the pulmonary hypertension associated with CREST syndrome has different pathogenesis from primary PH and to be classified as secondary PH.