Synthesis and characterization of ligustrazine-acylhydrazone derivatives and their inhibitory activity against human lung cancer A549 cells

Abstract: Background: Ligustrazine is a pivotal active component of Ligusticum wallichii Franch; it is used clinically for treating cardiovascular diseases. Derivatization of ligustrazine might promote its biological activities and bioavailability. Objectives: A series of ligustrazine-acylhydrazone derivatives (TMPAD-1–TMPAD-13) were synthesized and their inhibitory activity against A549 cells was investigated. Methods: These derivatives were synthesized by condensing aromatic aldehydes with ligustrazine-based hydrazides to form acylhydrazone bonds and their chemical structures were characterized through a combination of spectral methods, including Fourier transform infrared (FT-IR) spectroscopy, electrospray ionization high resolution mass spectrometry (ESI-HRMS), ¹H and ¹³C nuclear magnetic resonance (NMR) spectra. Results: In-vitro experimental results displayed that TMPAD-2 exhibited marked inhibitory activity against A549 cells as shown by impeding cell proliferation (IC₅₀ = 48.08 μmol/L), colony formation (colony forming efficiency ≤ 1.5 ± 0.02%), invasion and migration, enhancing tumor necrosis factor (TNF)-α and reactive oxygen species (ROS) levels, decreasing interleukin (IL)-6 and mitochondrial membrane potential (MMP) levels, hindering cell cycle progression and inducing apoptosis. RNA-sequencing (RNA-seq) analysis disclosed 17 lung cancer-related differentially expressed genes (DEGs). These results were statistically supported with significant p-value. Conclusion: These results suggest that dysregulation of the cyclin–cyclin-dependent kinase (CDK)–cyclin-dependent kinase inhibitor (CKI) regulatory network is primarily responsible for the inhibitory action of TMPAD-2 on A549 cells. Current findings might provide valuable insights for further development of ligustrazine derivatives as novel anticancer agents.