Effects of lettuce glycoside B in ameliorating pulmonary fibrosis induced by irradiation exposure and its anti-oxidative stress mechanism

Prevention of Bleomycin-Induced Pulmonary Inflammation and Fibrosis in Mice by Bilobalide

Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease. Bilobalide (BB) is a sesquiterpene isolated from Ginkgo biloba, and its role in IPF is poorly understood. Mice were intratracheally instilled with 2.5 mg/kg bleomycin (BLM) to induce IPF and then treated with 2.5, 5, and 10 mg/kg BB daily for 21 days. Treatment with BB ameliorated pathological injury and fibrosis of lung tissues in BLM-induced mice. BB suppressed BLM-induced inflammatory response in mice as demonstrated by reduced inflammatory cells counts (leukocytes, neutrophils, macrophages, and lymphocytes) and pro-inflammatory factors (CCL2 and TNF-α), as well as increased CXCL10 levels in BALF. The expression of BLM-induced hydroxyproline, LDH, and pro-fibrotic mediators including fibronectin, collagen I, α-smooth muscle actin (α-SMA), transforming growth factor (TGF)-β1, matrix metalloproteinase (MMP)-2, and MMP-9 in lung tissue was inhibited by BB treatment, and the tissue inhibitor of metalloproteinase-1 (TIMP-1) expression was increased. BB blocked the phosphorylation of JNK and NF-κB, and the nuclear translocation of NF-κB in the lung tissue of mice induced by BLM. Additionally, it abated the activation of NLRP3 inflammasome in lung tissue induced by BLM, which led to the downregulation of IL-18 and IL-1β in BALF. Our present study suggested that BB might ameliorate BLM-induced pulmonary fibrosis by inhibiting the early inflammatory response, which is probably via the inhibition of the JNK/NF-κB/NLRP3 signal pathway. Thus, BB might serve as a therapeutic potential agent for pulmonary inflammation and fibrosis.

The Effect of Ophiopogonin C in Ameliorating Radiation-Induced Pulmonary Fibrosis in C57BL/6 Mice: An Update Study

Background

The aim of this study was to assess and update the protective effects and underlying mechanisms of Ophiopogonin C (OP-C), a biologically active component separated and purified from Ophiopogon japonicus, in ameliorating radiation-induced pulmonary fibrosis in C57BL/6 mice administered thoracic radiation.

Methods and Materials

We randomly divided 75 mice into five groups and administered a dose of 12-Gy whole thoracic radiation to establish a pulmonary fibrosis animal model. Mice were treated with OP-C or dexamethasone combined with or without cephalexin by daily gavage for 4 weeks. All mice were sacrificed after the completion of thoracic irradiation at 28 weeks. Serum levels of interleukin-6 and transforming growth factor-β1 (TGF-β1) were evaluated. Moreover, superoxide dismutase (SOD) levels in lung tissue were measured. The severity of fibrosis was evaluated using the hydroxyproline content of the lung tissue. The pathological changes in the five groups were detected by hematoxylin and eosin and Masson trichrome staining. Smooth muscle actin expression was detected using immunohistochemical staining. Matrix metalloproteinases-2 (MMP-2) and tissue inhibitors of metalloproteases-2 (TIMP-2) were examined by immunohistochemical staining of the lung sections, and semiquantitative analysis was used to calculate the expression of MMP-2 and TIMP-2.

Results

Irradiated mice treated with OP-C or DXE combined with or without cephalexin significantly reduced mortality in mice and fibrosis levels by 1) reducing the deposition of collagen and accumulation of inflammatory cells and fibroblasts, 2) downgrading levels of the promote-fibrosis cytokine TGF-β1, and 3) increasing SOD activity in the lung tissue compared with that of irradiated mice without treatment. However, there were no statistical differences in fibrosis levels among the irradiated mice treated with OP-C or DXE combined with or without cephalexin.

Conclusion

OP-C significantly ameliorates radiation-induced pulmonary fibrosis and may be a promising therapeutic strategy for this disorder.

The role of natural products in the prevention and treatment of pulmonary fibrosis: a review

Pulmonary fibrosis is an incurable end-stage lung disease and remains a global public health problem. Although there have been some breakthroughs in understanding the pathogenesis of pulmonary fibrosis, effective intervention methods are still limited. Natural products have the advantages of multiple biological activities and high levels of safety, which are important factors for preventing and treating pulmonary fibrosis. In this review, we summarized the mechanisms and health benefits of natural products against pulmonary fibrosis. These natural products target oxidative stress, inflammatory injury, epithelial-mesenchymal transition (EMT), fibroblast activation, extracellular matrix accumulation and metabolic regulation, and the mechanisms involve the NF-κB, TGF-β1/Smad, PI3K/Akt, p38 MAPK, Nrf2-Nox4, and AMPK signaling pathways. We hope to provide new ideas for pulmonary fibrosis prevention and treatment strategies.

Pulmonary fibrosis: Therapeutic and mechanistic insights into the role of phytochemicals

Pulmonary fibrosis (PF) is the devastating consequence of various inflammatory diseases of the lung. PF leads to a reduction of lung function, respiratory failure, and death. Several molecular pathways are involved in PF, such as inflammatory cytokines including tumor necrosis factor α (TNFα), tumor necrosis factor β1 (TNFβ1), interleukin 6 (IL-6), and interleukin 4 (IL-4), reactive oxygen species, matrix metalloproteases, and transforming growth factor-beta (TGF-β). Targeting these processes involved in the progression of PF is essential for the treatment of this disease. Natural products, including plant extracts and active compound that directly target the processes involved in PF, could be suitable therapeutic options with less adverse effects. In the present study, we reviewed the protective effects and the therapeutic role of various bioactive compounds from plants in PF management.

Protective effects of Rosavin on bleomycin-induced pulmonary fibrosis via suppressing fibrotic and inflammatory signaling pathways in mice

Idiopathic Pulmonary fibrosis (IPF) is diagnosed as a life-threatening, progressive and incurable lung disease characterized by accumulation of extracellular matrix and myofibroblasts, resulting in the function degradation and structural alterations in normal lung parenchyma. Notably, Pulmonary Fibrosis has been considering as a difficult problem in clinical with high mortality and effective treatment strategies. Rosavin, a benzylPropylene glycoside, is isolated from Rhodiola rosea L., exhibiting nootropic, anti-depressant, anti-cancer, anti-inflammatory and anti-oxidative activities. In this study, we attended to elucidate the pharmacological activity of Rosavin for treatment of pulmonary fibrosis induced by bleomycin in mice. The results indicated that Rosavin could significantly ameliorate the lung index and Pathological structure of mice with Pulmonary fibrosis by bleomycin-induced. Additionally, Rosavin could evidently decreased inflammatory cells infiltration in bronchoalveolar lavage fluid and pro-inflammatory cytokines expression in lung tissue specimens induced by bleomycin. Rosavin could down-regulate the expression of hydroxyproline and malondialdehyde and increased the activities of superoxide dismutase, glutathione peroxidase in lung tissue. The expression of Nrf2 were increased, and the expression of NF-κB p65, TGF-β1 and α-SMA were inhibited. The findings revealed the protective effects and the primary mechanism of rosavin on bleomycin-induced pulmonary fibrosis, which provided a scientific foundation for Rosavin as a promising candidate for Pulmonary fibrosis treatment.

Cytokines and radiation-induced pulmonary injuries

Radiation therapy is one of the most common treatment strategies for thorax malignancies. One of the considerable limitations of this therapy is its toxicity to normal tissue. The lung is the major dose-limiting organ for radiotherapy. That is because ionizing radiation produces reactive oxygen species that induce lesions, and not only is tumor tissue damaged, but overwhelming inflammatory lung damage can occur in the alveolar epithelium and capillary endothelium. This damage may result in radiation-induced pneumonitis and/or fibrosis. While describing the lung response to irradiation generally, the main focus of this review is on cytokines and their roles and functions within the individual stages. We discuss the relationship between radiation and cytokines and their direct and indirect effects on the formation and development of radiation injuries. Although this topic has been intensively studied and discussed for years, we still do not completely understand the roles of cytokines. Experimental data on cytokine involvement are fragmented across a large number of experimental studies; hence, the need for this review of the current knowledge. Cytokines are considered not only as molecular factors involved in the signaling network in pathological processes, but also for their diagnostic potential. A concentrated effort has been made to identify the significant immune system proteins showing positive correlation between serum levels and tissue damages. Elucidating the correlations between the extent and nature of radiation-induced pulmonary injuries and the levels of one or more key cytokines that initiate and control those damages may improve the efficacy of radiotherapy in cancer treatment and ultimately the well-being of patients.