Histological and Physiological Studies of the Effect of Bone Marrow-Derived Mesenchymal Stem Cells on Bleomycin Induced Lung Fibrosis in Adult Albino Rats

Abstract

Background: Lung fibrosis is considered as an end stage for many lung diseases including lung inflammatory disease, autoimmune diseases and malignancy. There are limited therapeutic options with bad prognostic outcome. The aim of this study was to explore the effect of mesenchymal stem cells (MSCs) derived from bone marrow on Bleomycin (BLM) induced lung fibrosis in albino rats. Methods: 30 adult female albino rats were distributed randomly into 4 groups; negative control group, Bleomycin induced lung fibrosis group, lung fibrosis treated with bone marrow-MSCs (BM-MSCs) and lung fibrosis treated with cell free media. Lung fibrosis was induced with a single dose of intratracheal instillation of BLM. BM-MSCs or cell free media were injected intravenously 28 days after induction and rats were sacrificed after another 28 days for assessment. Minute respiratory volume (MRV), forced vital capacity (FVC) and forced expiratory volume 1 (FEV1) were recorded using spirometer (Power lab data acquisition system). Histological assessment was performed by light microscopic examination of H&E, and Masson’s trichrome stained sections and was further supported by morphometric studies. In addition, electron microscopic examination to assess ultra-structural changes was done. Confocal Laser microscopy and PCR were used as tools to ensure MSCs homing in the lung. Results: Induction of lung fibrosis was confirmed by histological examination, which revealed disorganized lung architecture, thickened inter-alveolar septa due excessive collagen deposition together with inflammatory cellular infiltration. Moreover, pneumocytes depicted variable degenerative changes. Reduction in MRV, FVC and FEV1 were recorded. BM-MSCs treatment showed marked structural improvement with minimal cellular infiltration and collagen deposition and hence restored lung architecture, together with lung functions. Conclusion: MSCs are promising potential therapy for lung fibrosis that could restore the normal structure and function of BLM induced lung fibrosis. Electronic supplementary material The online version of this article (10.1007/s13770-020-00294-0) contains supplementary material, which is available to authorized users.

Nintedanib reduces corticosteroid resistance pulmonary fibrosis induced by bleomycin in mice by increasing the expression of β3 & β6 integrins

“…Morphometric measurement after 7 days, the mean thickness of the interalveolar septa in (µm) and the mean alveolar space surface area (µm 2) after 7 days As the same mentioned in morphometric analysis (Zakaria et al, 2021). Blind histological analysis was performed on the lung paraffin sections from mice after 7 days for estimation of parenchymal distortion and airway (peribronchial) inflammation using specific semi-quantitative scores: Analysis of Lung parenchymal distortion: It was assessed by analysis of ten sequential non-overlapping tissue fields using x200 magnification.…”

“…Morphometric analysis after 28 days: measurement of the area percent of collagen fibers in Masson trichrome stain as same mentioned (Zakaria et al, 2021).They were measured by using the NIH Image J (v1.50) program and measurement of subepithelial connective tissue volume density (VVsub) in Masson trichrome stain after 28 days. Airway wall remodeling was evaluated by measurement of VV sub as the difference in the area, delimited by the basement membrane and the outer edge of the airway adventitia, divided by the length of subepithelial basement membrane (Polosukhin et al, 2012).…”

Nintedanib reduces corticosteroid resistance pulmonary fibrosis induced by bleomycin in mice by increasing the expression of β3 & β6 integrins

“…Morphometric measurement after 7 days, the mean thickness of the interalveolar septa in (µm) and the mean alveolar space surface area (µm 2) after 7 days As the same mentioned in morphometric analysis (Zakaria et al, 2021). Blind histological analysis was performed on the lung para n sections from mice after 7 days for estimation of parenchymal distortion and airway (peribronchial) in ammation using speci c semi-quantitative scores: Analysis of Lung parenchymal distortion: It was assessed by analysis of ten sequential non-overlapping tissue elds using x200 magni cation.…”

Dissecting the Role of Mesenchymal Stem Cells in Idiopathic Pulmonary Fibrosis: Cause or Solution

“…More recently, it was demonstrated that chronic Wnt/β-catenin activity in the IPF lung increased AECII senescence, leading to further progenitor cells dysfunction and impaired lung repair (Lehmann et al, 2020). In contrast, previous studies have shown that a particular lineage of Wnt responsive alveolar epithelial progenitor cells within the AECII population acted as a central player in lung regeneration after acute injury, being able to self-renew (Zacharias et al, 2018). Bolanos et al (2012) found that Shh pathway is activated in IPF lungs and might contribute to IPF pathogenesis by increasing fibroblast proliferation, migration and ECM production.…”

“…As IPF is usually diagnosed only after extensive fibrotic changes are present, this raises questions as to whether MSCs administration will be beneficial in IPF. However, in a recent study from Zakaria et al in albino rats BM-MSCs systemically administered 28 days after bleomycin-induction of lung damage; resulted in reversion of established fibrosis, restored lung architecture, and improved lung functions ( Zakaria et al, 2021 ). The mechanisms by which these effects occurred need further study and may open up better understanding that will support use of systemically administered MSCs in IPF.…”