Identification of Active Components and Multitarget Mechanism Study of Ephedra and Houttuynia Herb Powder in the Treatment of Mycoplasma Pneumonia in Calves.

Ephedra and Houttuynia Herb Powder (MHYXD) is a traditional Chinese herbal formula widely used in veterinary medicine to treat respiratory infections, such as mycoplasma pneumonia in calves, although its active components and pharmacological mechanisms have remained unclear. To address this, the present study identified the bioactive compounds in MHYXD using LC-MS, which revealed a total of 32 active compounds, with ephedrine, quercetin, and houttuynin being the most prominent. Network pharmacology and molecular docking approaches were employed to predict potential targets and pathways, indicating that MHYXD acts on multiple targets-including TNF-α, IL-6, and TLR4-and regulates the NF-κB and MAPK signaling pathways; molecular docking further confirmed strong binding affinities between key compounds and these target proteins. The antimycoplasma and anti-inflammatory effects of key components were validated through in vitro and in vivo experiments, which demonstrated that MHYXD significantly reduced mycoplasma load and alleviated lung inflammation in calves. In conclusion, this study elucidates the multicomponent, multitarget, and multipathway mechanisms of MHYXD in treating Mycoplasma pneumonia, thereby providing a scientific basis for its clinical application in veterinary medicine.