Study on the anti-atherosclerosis mechanisms of Tanyu Tongzhi formula based on network pharmacology, Mendelian randomization, and experimental verification.

Context: Tanyu Tongzhi Formula (TTF) exhibits potential against atherosclerosis; however, its mechanisms remain unclear.

Objective: This study explores the pharmacological mechanisms of TTF in treating atherosclerosis.

Materials and methods: Network pharmacology, molecular docking, mendelian randomization (MR), and liquid chromatography-mass spectrometry (LC-MS) analyses were utilized to reveal potential targets and compounds of TTF against atherosclerosis. After exploring the appropriate concentration of TTF to treat HCAECs using Cell Counting Kit-8 (CCK-8), the HCAECs were divided into three groups: control, oxidized low-density lipoprotein (ox-LDL, 50 μg/mL), and ox-LDL (50 μg/mL) + TTF (1 mg/mL). After 24-h incubation, the efficacy of TTF was verified by CCK-8, Oil red O staining, and ELISA. The expression of key targets was detected by real-time polymerase chain reaction (qPCR) and western blotting.

Results: A total of 137 active compounds and 127 potential TTF targets against atherosclerosis were identified. MR identified ALB, TNF, PPARα, and PPARγ as key targets. Molecular docking indicated that baicalin, naringenin, and curcumin exhibited suitable binding activities to these targets, further confirming by LC-MS analysis. The IC₅₀ of TTF in HCAECs was 18.25 mg/mL. TTF treatment significantly improved atherosclerosis by enhancing cell viability, reducing lipid accumulation, and inhibiting inflammation factors (IL6, IL1B and TNF-α) in ox-LDL-treated HCAECs. Moreover, qPCR or western blotting indicated that TTF could up-regulate PPARα and PPARγ while down-regulate TNF expression.

Discussion and conclusions: Our results revealed active compounds, key pathways, and core targets of TTF against atherosclerosis, providing experimental support for its application in treating of atherosclerosis.