ESL attenuates BLM-induced IPF in mice: Dual mediation of the TLR4/NF-κB and TGF-ß1/PI3K/Akt/FOXO3a pathways.

BACKGROUNDS: Idiopathic pulmonary fibrosis (IPF) is a persistent and advanced pulmonary ailment. The roles of innate immunity and adaptive immunity are pivotal in the evolution of IPF. An ill-adjusted interaction between epithelial cells and immune cells is responsible for initiating the epithelial-mesenchymal transition (EMT) process and sustaining chronic inflammation, thereby fostering fibrosis progression. The intricacy of IPF pathogenesis has hindered the availability of efficacious agents. Elephantopus scaber Linn. (ESL) is a canonical Chinese medicine with significant immunoregulatory effects, and its aqueous extract has been proven to attenuate IPF symptoms in bleomycin (BLM)-induced mice. However, the underlying mechanism through which ESL relieves IPF remains unclear. AIM: To validate whether ESL reverses IPF by mediating the immune response and EMT. METHODS: Ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS) and UPLC were used to identify the components and determine the concentrations of the specific compounds in the ESL. Network pharmacology and molecular docking were applied to predict the potential mechanism underlying the anti-IPF effect of ESL. BLM-induced IPF mice were used to validate the anti-IPF effect of ESL, and lung tissue was collected to test putative pathways involved in inflammation and EMT via immunohistochemistry (ICH), real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting. RESULTS: Sixty-one compounds were identified, and thirteen main ingredients were quantified in the ESL. In silico experiments predicted that the IPF-mediated reversal of adverse effects by ESL would be related to interruption of the Toll-like receptor 4 (TLR4)/nuclear factor-k-gene binding (NF-ĸB) inflammatory pathway and the transforming growth factor-beta l (TGF-ß1)/phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/forkhead box O3 (FOXO3a) fibrosis pathway. In vivo experiments showed that ESL alleviates BLM-induced lung inflammation and fibrosis by reducing neutrophil aggregation and fibroblast foci, similar to the effects of the positive control drug pirfenidone (PFD). ESL markedly inhibited the transcription of TNF-α, IL-1ß, and IL-6, which are downstream genes of the NF-κB signaling pathway. Furthermore, the protein levels of TLR4 and p-NF-κB were correspondingly inhibited in response to ESL treatment. Additionally, ESL reverses BLM-induced changes in the expression of EMT-related biological characteristic indicators (collagen I [COLIA1], E-cadherin, and alpha smooth muscle actin [α-SMA]) at the messenger ribonucleic acid (mRNA) level and markedly inhibits the expression of EMT-related upstream proteins (TGF-ß1, p-PI3K, p-Akt, and p-FOXO3a). CONCLUSION: Our research suggested that ESL attenuates BLM-induced IPF through mediating the EMT process via the TGF-ß1/PI3K/Akt/FOXO3a signaling pathway and inhibiting inflammation through the TLR4/NF-κB signaling pathway, highlighting that ESL can serve as an immunoregulator for relieving the abnormal immune response and reversing the EMT in IPF.

Selection and evaluation of quality markers for the regulation of PXR-CYP3A4/FXR-LXRα by Exocarpium Citri Grandis for the treatment of hyperlipidaemia with dispelling blood stasis and removing phlegm.

Hyperlipidaemia is described as "excessive phlegm" and "blood stasis" in the classic theory of traditional Chinese medicine. Exocarpium Citri Grandis has the effect of dispelling blood stasis and removing phlegm, which can better meet the treatment needs of this disease. However, there is still a lack of focus and depth in the study of the chemical composition of this medicine, and the correlation between the study of relevant medicinal substances and the efficacy of dispelling stasis and removing phlegm is insufficient. To address this issue, this study was carried out to validate the overall efficacy and identify and determine the chemical composition of Exocarpium Citri Grandis. The regulatory mechanism of the PXR-CYP3A4/FXR-LXRα pathway and its active ingredients were screened, and a pharmacokinetic study of active ingredients was performed. The obtained multidimensional data were statistically analysed and comprehensively evaluated. The quality marker of Exocarpium Citri Grandis in the treatment of hyperlipidaemia based on the PXR-CYP3A4/FXR-LXRα mechanism to exert the efficacy of dispelling blood stasis and removing phlegm was finally determined. Based on the above experiments, we identified 27 compounds from the ethanol extract of Exocarpium Citri Grandis. Among them, naringenin, meranzin hydrate, apigenin, caffeic acid phenethyl ester, anacardiin, hesperidin and naringin can significantly regulate all or part of the targets in the PXR-CYP3A4/FXR-LXRα pathway. It also has suitable content and pharmacokinetic characteristics in vivo. In conclusion, this study established quality markers to characterize the efficacy of Exocarpium Citri Grandis in dispelling blood stasis and removing phlegm, which provides a scientific basis for the targeted evaluation of the hypolipidaemic activity of this medicinal plant.