Chinese herbal component, Praeruptorin E, enhances anti-asthma efficacy and prevents toxicity of aminophylline by targeting the NF-κB/PXR/CYP3A4 pathway

Ronghua Xu; Huiming Deng; Lianfang Gan; Lifan Zhong; Yanxi Deng; Qianru Wang; Chuanzhu Lv; Ling Huang

doi:10.21037/atm-22-386

Chinese herbal component, Praeruptorin E, enhances anti-asthma efficacy and prevents toxicity of aminophylline by targeting the NF-κB/PXR/CYP3A4 pathway

Ann Transl Med. 2022 Feb;10(4):225. doi: 10.21037/atm-22-386.

Authors

Ronghua Xu^#^{1

2}, Huiming Deng^#^{1

2}, Lianfang Gan^#¹, Lifan Zhong¹, Yanxi Deng¹, Qianru Wang¹, Chuanzhu Lv^{3

4}, Ling Huang^{1

4

5}

Affiliations

¹ Hainan Province Key Laboratory for Drug Preclinical Study of Pharmacology and Toxicology Research, Hainan Medical University, Haikou, China.
² Department of Gastrointestinal Surgery, Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen, China.
³ Key Laboratory of Emergency and Trauma of Ministry of Education, Hainan Medical University, Haikou, China.
⁴ Research Unit of Island Emergency Medicine, Chinese Academy of Medical Sciences, Hainan Medical University, Haikou, China.
⁵ School of Hainan Provincial Drug Safety Evaluation Research Center, Hainan Medical University, Haikou, China.

^# Contributed equally.

Abstract

Background: Aminophylline is widely used for the treatment of asthma, but the therapeutic dose is very close to the toxic dose, which makes this drug prone to accumulation poisoning. In the present study, we explored whether the Chinese herbal component, Praeruptorin E (PE), enhances anti-asthma efficacy and prevents the toxicity of aminophylline.

Methods: First, an ovalbumin (OVA)-induced mouse model of asthma, immunohistochemistry, pathological staining, and bronchoalveolar lavage fluid (BALF) were used to detect the lung condition of asthmatic mice. The content of Th2 cytokines in serum was measured by enzyme-linked immunosorbent assay (ELISA), and the expression of related proteins was detected by Western blotting and immunofluorescence. Concentrations of theophylline and its metabolites in rat serum were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). siRNA transfection and chromatin immunoprecipitation (ChIP) were used to investigate the mechanism of PE.

Results: PE was found to synergize with aminophylline to reduce the infiltration of inflammatory cells, collagen deposition, and mucus hyperplasia in the lungs of asthmatic mice. It inhibited the expression of Th2 cytokines, interleukin (IL)-4, IL-5, and IL-13; promoted lung tissue repair; and reduced the toxic effect of aminophylline on the heart. Moreover, LC-MS/MS analysis showed that PE reduced the plasma concentration of the parent theophylline and its metabolite 1,3-dimethyluric acid (1,3-DMU). PE facilitated aminophylline's suppression of nuclear factor-κB (NF-κB), and increased the expression of the xenobiotic nuclear receptor pregnane X receptor (PXR) and its primary target gene, CYP3A11 [this is the mouse homolog of cytochrome P450 3A (CYP3A)] in the asthmatic mouse liver and in the L-02 human fetal hepatocyte cell culture model. In addition, the ChIP assay revealed that PE attenuated the binding of NF-κB to the promoter region of the PXR gene and prevented the suppression of PXR gene expression by NF-κB.

Conclusions: PE has a dual function in enhancing the immune regulation and anti-inflammatory effects of theophylline, as well as preventing theophylline toxicity by targeting the NF-κB/PXR/CYP3A4 axis. PE is a promising herbal medicine that will benefit asthmatics taking theophylline.

Keywords: Praeruptorin E (PE); aminophylline; asthma; nuclear factor-κB (NF-κB); pregnane X receptor (PXR).