Agastache rugosa extract, containing the active component rosmarinic acid, prevents atherosclerosis

Agastache rugosa (FiSCH & C. Meyer) Kuntze [Lamiaceae], commonly known as Korean mint, has traditionally been used for both food and medicine, depending on which part of the plant is used (e.g., sprouts, shoots, or aerial parts). In addition, A. rugosa has been reported to possess a variety of pharmacological and physiological activities [1]. In the present study, we investigated the anti-proliferative activities of A. rugosa extract in vascular smooth muscle cells (VSMCs) and analysed several molecular pathways to determine the active component of the extract. To identify the anti-proliferative effects of A. rugosa extract, we performed several assays in VSMCs stimulated with platelet derived-growth factor (PDGF)-BB. A. rugosa extract inhibited PDGF-BB-stimulated VSMC proliferation and DNA synthesis. A. rugosa extract caused arrest of the cell cycle at the G₀/G₁ transition, which is stimulated by PDGF-BB, and the activity of several relevant cell cycle-related proteins was also suppressed in the presence of A. rugosa extract [2]. Correspondingly, the levels of p21^WAF1/CIP1 and p27^KIP1 were significantly up-regulated according to the immunoblotting and immunofluorescence assays in a concentration-dependent manner [3]. To determine the active component, we used HPLC followed by DNA synthesis and PCNA expression analyses. Among the components of the A. rugosa extract reported in a previous study, including chlorogenic acid, caffeic acid (CA), calycosin-7-O-β-D-glucoside, rosmarinic acid (RA) [4], calycosin, and genistein. However, only CA and RA were detected in the aqueous extract of A. rugosa. Finally, we showed that RA inhibited DNA synthesis and suppressed PCNA expression in a dose-dependent manner. These results indicate that A. rugosa extract, which includes the active component RA, demonstrates anti-proliferative activity by arresting the cell cycle at the G₀/G₁ phase through the upregulation of p21^WAF1/CIP1 and p27^Kip1 expression.

Acknowledgements: This work was supported by a grant (K16281) awarded to the KIOM from the Ministry of Science, ICT and Future Planning (MISP), Republic of Korea.

Keywords: Anti-proliferative activity, Agastache rugosa Kuntze, cell cycle, cyclin-dependent kinase inhibitor, rosmarinic acid.

References:

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