Combining transcriptomics and network pharmacology to reveal the mechanism of Zuojin capsule improving spasmolytic polypeptide-expressing metaplasia

Spasmolytic polypeptide-expressing metaplasia (SPEM) is a gastric precancerous lesion (GPL). Zuojin capsule (ZJC), consisting of Coptis chinensis Franch. (Ranunculaceae, recorded in the Chinese Pharmacopoeia as Rhizoma Coptidis) and Tetradium ruticarpum (A.Juss.) T.G.Hartley (Rutaceae, recorded in the Chinese Pharmacopoeia as Fructus Evodiae), has long been used for various gastrointestinal diseases. However, the effect and mechanism of ZJC on SPEM remain unclear.To clarify the role of ZJC in improving SPEM and study its mechanism.The study utilized SPEM mice induced by 250 mg/kg body weight of tamoxifen (TAM) to assess the effects of ZJC and investigate its possible mechanisms. A strategy of transcriptomics combined with network pharmacology was conducted to explore the targets and mechanisms of ZJC in improving SPEM. The "ingredients-target-pathway" network was constructed, and the possible connections were verified by RT-qPCR and Western blot assays.ZJC significantly attenuated the abnormal serological indices, destruction of the gastric mucosal structure, hyperplasia of gastric pits, increased gastric mucus, massive secretion of CD44 and TFF2, oxyntic atrophy and massive proliferation of stem/progenitor cells in TAM-induced SPEM mice. Combined transcriptomics and network pharmacology analysis, 50 core targets of ZJC related to SPEM improvement were obtained. KEGG results showed that the core targets were significantly enriched in the cell cycle, and PI3K-AKT signaling pathway. The top-ranked targets according to PPI network analysis were CDK1, CCNB1, and CCNA2, which are also associated with cell cycle. Combined experiments demonstrated that ZJC can induce G2/M phase cycle arrest and inhibit TAM-induced malignant proliferation by regulating abnormal activation of cell cycle-related proteins such as CDK1, CCNB1, CCNA2 and PI3K-AKT signaling pathways.ZJC may improve TAM-induced SPEM by inhibiting abnormal activation of cell cycle-related proteins (CDK1, CCNB1, CCNA2) and PI3K-AKT signaling pathway. This finding supports the use of ZJC, a famous traditional Chinese medicine compound, as a potential treatment for gastric precancerous lesions.