• Toxicological Research
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• 제24권4호
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• pp.273-280
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• 2008

The single intratracheal instillation (ITI) of bleomycin (BLM) is a widely used method for inducing experimental pulmonary fibrosis in rat model. In the present study, pulmonary function tests (PFTs) of tidal volume ($V_T$), minute volume ($V_M$), and respiratory frequency ($F_R$) have been applied to study their possibility as a tool to monitor the progress of BLM-induced lung injury in rat model. Rats were treated with a single ITI of BLM (2.5 mg/kg) or saline (control). Animals were euthanized at 3, 7, 14, 21, and 28 days post-ITI. Lung toxicity effects were evaluated by inflammatory cell count, lactate dehydrogenase (LDH) activity in the bronchoalveolar lavage fluid (BALF), and light microscopic examination of lung injury. The PFT parameters were measured immediately before the animals were sacrificed. BLM treatment induced significant cellular changes in BALF-increase in number of total cells, neutrophils, and lymphocytes along with sustained increase in number of macrophages compared to the controls at days 3, 7, and 14. BALF LDH level was significantly increased compared to that in the controls up to day 14. On day 3, infiltration of neutrophils was observed in the alveolar spaces. These changes developed into marked peribronchiolar and interstitial infiltration by inflammatory cells, and extensive thickening of the interalveolar septa on day 7. At 14, 21, and 28 days, mild peribronchiolar fibrosis was observed along with inflammatory cell infiltration. The results of PFT show significant consistencies compared to the results of other toxicity tests. These data demonstrate that the most suitable time point for assessing lung fibrosis in this model is 14 days post-ITI of BLM based on the observation of fibrosis at 14, 21, and 28 days. Further, the progress of lung injury can be traced by monitoring the PFT parameters of $F_R$, $V_T$, and $V_M$.

• Tuberculosis and Respiratory Diseases
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• 제70권6호
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• pp.462-473
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• 2011

Background: Smoking is a risk factor for idiopathic pulmonary fibrosis (IPF), but the mechanism of the association remains obscure. There is evidence demonstrating that plasminogen activator inhibitor-1 (PAI-1) is involved in the progression of pulmonary fibrosis. This study was to determine whether the administration of small interfering RNA (siRNA) targeting PAI-1 or PAI-1 inhibitor to the cigarette smoking extract (CSE)-exposed rat alveolar type II epithelial cells (ATII cells) limits the epithelial-mesenchymal transition (EMT). Methods: ATII cells were isolated from lung of SD-rat using percoll gradient method and cultured with 5% CSE. The EMT was determined from the ATII cells by measuring the real-time RT PCR and western blotting after the PAI-1 siRNA transfection to the cells and after administration of tiplaxtinin, an inhibitor of PAI-1. The effect of PAI-1 inhibitor was also evaluated in the bleomycin-induced rats. Results: PAI-1 was overexpressed in the smoking exposed ATII cells and was directly associated with EMT. The EMT from the ATII cells was suppressed by PAI-1 siRNA transfection or administration of tiplaxtinin. Signaling pathways for EMT by smoking extract were through the phosphorylation of SMAD2 and ERK1/2, and finally Snail expression. Tiplaxtinin also suppressed the pulmonary fibrosis and PAI-1 expression in the bleomycin-induced rats. Conclusion: Our data shows that CSE induces rat ATII cells to undergo EMT by PAI-1 via SMAD2-ERK1/2-Snail activation. This suppression of EMT by PAI-1 siRNA transfection or PAI-1 inhibitor in primary type II alveolar epithelial cells might be involved in the attenuation of bleomycin-induced pulmonary fibrosis in rats.

• Tuberculosis and Respiratory Diseases
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• 제50권4호
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• pp.504-509
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• 2001

There are numerous agents with potential toxic effects on the lung. In particular, cytotoxic drugs constitute the largest and most important group of agents associated with lung toxicity. Bleomycin is commonly used, either alone or in combination with other chemotherapeutic agents, in the treatment of squamous cell carcinoma(head and neck, esophagus, and genitourinary tract), lymphoma, and germ cell tumor. One of the therapeutic advantages of bleomycin is its minimal bone marrow toxicity. However, pulmonary toxicity is one of the most serious adverse side effects. Classically, pulmonary toxicity manifests as a diffuse interstitial process or less commonly as a hypersensitivity reaction. This pulmonary toxicity is generally considered to be dose related and can progress to a fatal fibrosis. It is also possible that bronchiolitis obliterans organizing pneumonia(BOOP) is another manifestation of bleomycin induced toxicity. Bleomycin induced BOOP is less common and has a favorable response to steroid therapy. Here we present a case that demonstrates a BOOP, secondary to a relatively small cumulative dose of bleomycin($225mg/m^2$), may be reversible.

• IMMUNE NETWORK
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• 제23권6호
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• pp.45.1-45.22
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• 2023

Interstitial lung disease (ILD) involves persistent inflammation and fibrosis, leading to respiratory failure and even death. Adult tissue-derived mesenchymal stem cells (MSCs) show potential in ILD therapeutics but obtaining an adequate quantity of cells for drug application is difficult. Daewoong Pharmaceutical's MSCs (DW-MSCs) derived from embryonic stem cells sustain a high proliferative capacity following long-term culture and expansion. The aim of this study was to investigate the therapeutic potential of DW-MSCs in experimental mouse models of ILD. DW-MSCs were expanded up to 12 passages for in vivo application in bleomycin-induced pulmonary fibrosis and collagen-induced connective tissue disease-ILD mouse models. We assessed lung inflammation and fibrosis, lung tissue immune cells, fibrosis-related gene/protein expression, apoptosis and mitochondrial function of alveolar epithelial cells, and mitochondrial transfer ability. Intravenous administration of DWMSCs consistently improved lung fibrosis and reduced inflammatory and fibrotic markers expression in both models across various disease stages. The therapeutic effect of DW-MSCs was comparable to that following daily oral administration of nintedanib or pirfenidone. Mechanistically, DW-MSCs exhibited immunomodulatory effects by reducing the number of B cells during the early phase and increasing the ratio of Tregs to Th17 cells during the late phase of bleomycin-induced pulmonary fibrosis. Furthermore, DW-MSCs exhibited anti-apoptotic effects, increased cell viability, and improved mitochondrial respiration in alveolar epithelial cells by transferring their mitochondria to alveolar epithelial cells. Our findings indicate the strong potential of DW-MSCs in the treatment of ILD owing to their high efficacy and immunomodulatory and anti-apoptotic effects.

• Journal of Applied Biological Chemistry
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• 제65권4호
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• pp.357-365
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• 2022

Flavonoid 골격 중 flavanone과 flavone 골격 화합들의 유용성과 가능성에 대해 여러 연구들이 되어있다. 본 연구의 목적은 폐섬유화에 대한 치료물질로서 효능이 있는 flavanone 및 flavone 골격 유래 화합물들을 탐색하는 것에 있다. Flavanone 및 flavone 골격 유래 화합물들이 폐섬유화 억제 효능이 있는지 탐색하기 위해 폐섬유화 유도 물질인 bleomycin과 TGF-β1으로 자극한 A549 세포에서 flavanone 및 flavone 골격 유래 화합물들에 의해 폐섬유증 마커들을 약화시키는지 여부를 확인하였다. 실험 결과를 종합해보면 7,2',3'-trimethoxyflavanone(ICC no. 3), 7,3'-dimethoxyflavone (ICC no. 5), 2'-hydroxyflavanone (ICC no. 6)은 폐섬유화 유도관련 단백질 마커들의 발현을 감소시킨다는 것을 발견하였다. 본 연구에서는 이러한 결과들을 통해 flavanone과 flavone 골격 화합물 중 3가지가 폐섬유증의 예방과 치료에 대한 가능성이 있음을 제시한다.

• Tuberculosis and Respiratory Diseases
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• 제42권2호
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• pp.184-205
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• 1995

연구배경: Bleomycin(BLM) 투여로 유발되는 폐손상 및 폐섬유화는 특발성 폐섬유증의 실험적 모델로써 BLM의 폐독성 기전은 산소유리기에 의한 직접 독성과 염증세포, 섬유모세포 및 세포외 기질에 의한 간접 독성으로 나누어 설명하고 있다. 이에 저자는 폐손상의 주요 원인이 되는 산소유리기의 생성과 이미 형성된 산소유리기를 보집할 수 있는 산화방지제들을 투여함으로써, BLM에 의한 폐손상 및 폐섬유화의 발생과 그 억제기전을 이해하고자 본 실험을 시행하였다. 방법: 웅성 백서에 폐손상 및 폐섬유화의 대표적인 실험적 방법인 bleomycin (BLM)을 투여함과 동시에 산화방지제로 구리의 킬레이트제인 penicillamine, 철의 킬레이트제인 deferoxamine과 산소유리기의 보집제인 vitamine E를 투여한 후 그 형태학적 변화를 보기 위해 기관지폐포 세척액 검사, 광학현미경 소견과 세포외 기질인 교원섬유 제 I, III, IV형과 비교원성 기질인 fibronectin과 laminin 그리고 근섬유모세포에 대한 NBD phallicidin에 대한 면역형광염색 및 면역조직화학염색소견을 관찰하여 다음과 같은 결과를 얻었다. 결과: 1) 기관지폐포세척액의 검사소견상 총 세포수는 BLM 단독투여군의 경우 제4일에 최고값에 도달한 후 감소하기 시작하여 제28일에 대조군과 비슷해졌지만, penicillamine과 deferoxamine 처치군은 제1일부터 제28일까지 계속 높았으며, vitamin E 처치군은 제3일부터 현저한 차이로 감소하여 제7일부터 대조군과 비슷해졌다. 기관지폐포 세척액의 각 염증세포구성비는 BLM 단독투여군은 초기 즉 제1, 3, 4일에 중성구가 현저히 증가하다가 제7일부터 감소하여 제28일에 대조군과 비슷해졌지만, vitamin E 처치군은 중성구가 제3일부터 BLM 단독투여군의 1/3이하로 현저히 감소하였다. 2) 광학현미경소견은 BLM 단독투여군의 경우 다른 실험군에 비해 섬유화가 가장 심하였고, penicillamine 처치군은 중성구의 침윤이 지속적으로 많았으며, deferoxamine 처치군은 폐포 중격의 림프구 침윤이 뚜렷하였고, vitamin E 처치군은 페포 중격 및 폐포강내 대식세포 증가가 많았다. 이러한 소견은 기관지폐포세척액 소견과 잘 일치하였다. 산화방지제 처치군의 섬유화 소견은 deferoxamine 처치군이 가장 뚜렷하였고, penicillamine 처치군은 적었지만 관찰되었으며, vitamin E 처치군은 거의 없었다. 3) 세포외 기질의 변화로 폐포 간질의 기저막에 양성반응을 나타내는 제 IV형 교원섬유와 laminin 및 Jones' methenamine silver 염색결과는 비슷한 양상이었는데, BLM 단독투여군, penicillamine 처치군과 deferoxamine 처치군은 모두 제28일군에서 음성반응을 나타냈으나, vitamin E 처치군은 제28일까지 대조군과 비슷하게 기저막이 유지되었다. 섬유화 부위에 증가된 세포외 기질은 제 I 형 교원섬유와 fibronectin 이었으며, 제 III 형 교원섬유는 각 국에서 초기에 일시적으로 양성반응을 나타내었다. NBD phallicidin은 BLM 단독투여군에서 특히 제 28일군 육아조직의 방추형세포에 양성반응을 보였다. 결론: Bleomycin 투여에 의한 폐손상 및 폐섬유화 기전은 bleomycin이 구리 또는 철 이온의 존재하에 생성한 산소유리기에 의해 유발될 수도 있으나, 주로 중성구의 활성화로 인한 산소유리기에 의해 유발되고, 폐의 섬유화 제 I 형 교원섬유와 fibronectin의 증가로 초래되었다. 폐손상의 억제는 킬레이트제 보다는 산소유리기의 보집제인 vitamin E 투여시 가장 효과가 있었는데 이것은 초기의 중성구 증가 및 중성구의 활성화 정도에 따라 간질내 폐포의 기저막 유지 및 재생이 가능하고 이것이 폐의 탄력성을 유지시켜 폐손상을 억제할 수 있기 때문으로 사료된다.

• Journal of Ginseng Research
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• 제47권4호
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• pp.543-551
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• 2023

Background: Panax ginseng Meyer is a representative Chinese herbal medicine with antioxidant and anti-inflammatory activity. 20(S)-Protopanaxadiol (PPD) has been isolated from ginseng and shown to have promising pharmacological activities. However, effects of PDD on pulmonary fibrosis (PF) have not been reported. We hypothesize that PDD may reverse inflammation-induced PF and be a novel therapeutic strategy. Methods: Adult male C57BL/6 mice were used to establish a model of PF induced by bleomycin (BLM). The pulmonary index was measured, and histological and immunohistochemical examinations were made. Cell cultures of mouse alveolar epithelial cells were analyzed with Western blotting, coimmunoprecipitation, immunofluorescence, immunohistochemistry, siRNA transfection, cellular thermal shift assay and qRT-PCR. Results: The survival rate of PPD-treated mice was higher than that of untreated BLM-challenged mice. Expression of fibrotic hallmarks, including α-SMA, TGF-β1 and collagen I, was reduced by PPD treatment, indicating attenuation of PF. Mice exposed to BLM had higher STING levels in lung tissue, and this was reduced by phosphorylated AMPK after activation by PPD. The role of phosphorylated AMPK in suppressing STING was confirmed in TGF-b1-incubated cells. Both in vivo and in vitro analyses indicated that PPD treatment attenuated BLM-induced PF by modulating the AMPK/STING signaling pathway. Conclusion: PPD ameliorated BLM-induced PF by multi-target regulation. The current study may help develop new therapeutic strategies for preventing PF.

• Tuberculosis and Respiratory Diseases
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• 제44권4호
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• pp.871-888
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• 1997

연구배경 : 특발성 폐 섬유화확 병인론으로 폐포염과 폐에 침윤한 염증세포 및 폐 조직자체의 실질세포들이 성장인자를 포함한 다양한 cytokine을 분비하여 실질조직을 구성하는 세포에 손상을 야기함으로써 종국에는 섬유화를 초래하는 것으로 이해하고 있다. 그러나 이들에 대한 개괄적인 연구가 부족하고 매개체 각각에 대한 단편적인 논문들뿐이어서 본 연구에서는 BLM유도 폐 손상및 섬유화의 발생기전에 있어서 IL-1, IL-6, TNF-$\alpha$와 TGF-${\beta}_1$, PDGF, bFGF들의 역할을 규명하고자 하였다. 방 법 : Wistar백서를 정상대조군, BLM투여군, BLM과 비타민 E병합투여군으로 나누었고 BLM 투여후 제 1, 2, 3, 4, 5, 7, 14, 21, 28일에 각각 도살한 다음 기관지폐포 세척술을 시행하여 시기별 총 세포수, 세포 구성성분비율을 살펴보았고 TGF-${\beta}_1$, PDGF, bFGF, IL-1, IL-6, TNF-$\alpha$에 대한 면역조직화학 염색, TGF-${\beta}_1$ mRNA에 대한 동소보합결합검사를 시행, 각 매개체의 생성소, 발현분포 및 정도를 분석하였다. 결 과 : BLM 투여후 1~7 일에 중성구와 기관지상피세포에서 생성된 IL-1, IL-6는 폐손상부위로 원하는 것으로 생각되며 7일이내에 기관지상피세포에서의 IL-1, IL-6 의 양성발현은 기관지상피세포가 BLM 유도 폐 섬유화시 기도주변에서 일어나는 염증 및 면역반응을 항진 및 유지시키는 간접증거로 생각된다. TNF-$\alpha$는 BLM투여후 1~5일에는 기관지상피세포, 중성구가 주생성소로 폐손상부위로의 염증세포의 이동에 주요역할을 하는 것으로 생각되며 7~28일에는 대식세포가 주생성소로서 섬유화를 촉진시키는 것으로 생각된다. TGF-${\beta}_1$은 기관지 상피세포, 대식세포가 주생성소로서 섬유모세포가 표적세포로 생각되며 섬유모세포가 세포외 기질을 생성하도록 자극하고 대식세포에서 유리된 PDGF와 함께 섬유모세포의 증식을 자극한다. 대식세포 및 섬유모세포에서 유리된 bFGF는 TGF-${\beta}_1$과 함께 교원질과 같은 세포외기질의 생성을 자극하는 것으로 여겨진다. 비타민 E와 BLM 병합투여군의 경우 6가지 성장인자 및 cytokine의 발현세포는 같았으나 발현세포수는 극히 미미하였고 trichrome염색상 섬유화도 미약하였다. 결 론 : BLM으로 인한 혈관내피 및 폐포상피세포 손상이후 침윤한 중성구 및 기관지 상피세포가 IL-1, IL-6, TNF-$\alpha$를 분비하여 BLM투여 1~7 일에 많은 수의 중성구를 동원하도록 유도하며 이들이 유리하는 다양한 효소 및 산소유리기가 폐의 정상구조를 파괴하여 섬유화를 시작하게 하는 것으로 생각한다. 손상이 진행됨에 따라 BLM투여 7~28 일에 대식세포가 유리하는 TGF-${\beta}_1$, PDGF, bFGF, TNF-$\alpha$는 섬유모세포를 자극, 이들의 증식을 유도하고 또한 세포외기질의 생성증가를 유도하여 폐 섬유화를 진행시키는 것으로 사료되며 TNF-$\alpha$는 BLM투여후 전 기간에 걸쳐 다수의 세포에서 발현된 점으로 미루어 섬유화에 있어서 TGF-${\beta}_1$ 못지않은 중요한 역할을 하는 것으로 여겨진다. 또한 비타민 E가 BLM유도 폐 손상으로 인한 폐 섬유화의 정도를 감소시키는 것으로 생각한다.

• Tuberculosis and Respiratory Diseases
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• 제82권2호
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• pp.133-142
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• 2019

Background: Idiopathic pulmonary fibrosis involves irreversible alveolar destruction. Although alveolar epithelial type II cells are key functional participants within the lung parenchyma, how epithelial cells are affected upon bleomycin (BLM) exposure remains unknown. In this study, we determined whether BLM could induce cell cycle arrest via regulation of Schlafen (SLFN) family genes, a group of cell cycle regulators known to mediate growth-inhibitory responses and apoptosis in alveolar epithelial type II cells. Methods: Mouse AE II cell line MLE-12 were exposed to $1-10{\mu}g/mL$ BLM and $0.01-100{\mu}M$ baicalein (Bai), a G1/G2 cell cycle inhibitor, for 24 hours. Cell viability and levels of pro-inflammatory cytokines were analyzed by MTT and enzyme-linked immunosorbent assay, respectively. Apoptosis-related gene expression was evaluated by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR). Cellular morphology was determined after DAPI and Hoechst 33258 staining. To verify cell cycle arrest, propidium iodide (PI) staining was performed for MLE-12 after exposure to BLM. Results: BLM decreased the proliferation of MLE-12 cells. However, it significantly increased expression levels of interleukin 6, tumor necrosis factor ${\alpha}$, and transforming growth factor ${\beta}1$. Based on Hoechst 33258 staining, BLM induced condensation of nuclear and fragmentation. Based on DAPI and PI staining, BLM significantly increased the size of nuclei and induced G2/M phase cell cycle arrest. Results of qRT-PCR analysis revealed that BLM increased mRNA levels of BAX but decreased those of Bcl2. In addition, BLM/Bai increased mRNA levels of p53, p21, SLFN1, 2, 4 of Schlafen family. Conclusion: BLM exposure affects pulmonary epithelial type II cells, resulting in decreased proliferation possibly through apoptotic and cell cycle arrest associated signaling.

• Toxicological Research
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• 제30권2호
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• pp.83-90
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• 2014

An increasing number of recent studies have focused on the impact of particulate matter on human health. As a model for atmospheric particulate inhalation, we investigated the effects of inhaled carbon black nanoparticles (CBNP) on mice with bleomycin-induced pulmonary fibrosis. The CNBPs were generated by a novel aerosolization process, and the mice were exposed to the aerosol for 4 hours. We found that CBNP inhalation exacerbated lung inflammation, as evidenced by histopathology analysis and by the expression levels of interleukin-6 protein, fibronectin, and interferon-${\gamma}$ mRNAs in lung tissues. Notably, fibronectin mRNA expression showed a statistically significant increase in expression after CBNP exposure. These data suggest that the concentration of CBNPs delivered (calculated to be $12.5{\mu}g/m^3$) can aggravate lung inflammation in mice. Our results also suggest that the inhalation of ultrafine particles like PM 2.5 is an impactful environmental risk factor for humans, particularly in susceptible populations with predisposing lung conditions.