Induction of apoptosis by Moutan Cortex Radicis in human gastric cancer cells through the activation of caspases and the AMPK signaling pathway

Abstract Moutan Cortex Radicis, the root bark of Paeonia × suffruticosa Andrews, Paeoniaceae, has been widely used in traditional medicine therapy. Although it has been shown to possess many pharmacological activities, the molecular mechanisms of its anti-cancer activity have not been clearly elucidated. In the present study, we investigated the pro-apoptotic effects of the ethanol extract of Moutan Cortex Radicis in human gastric cancer AGS cells. Moutan Cortex Radicis treatment inhibited the cell viability of AGS cells in a concentration-dependent manner, which was associated with apoptotic cell death. Moutan Cortex Radicis's induction of apoptosis was connected with the upregulation of death receptor 4, death receptor 5, tumor necrosis factor-related apoptosis-inducing ligand, Fas ligand, and Bax, and the downregulation of Bcl-2 and Bid. Moutan Cortex Radicis treatment also induced the loss of mitochondrial membrane potential (Δψm), the proteolytic activation of caspases (-3, -8, and -9), and the degradation of poly(ADP-ribose) polymerase, an activated caspase-3 substrate protein. However, the pre-treatment of a caspase-3 inhibitor significantly attenuated Moutan Cortex Radicis-induced apoptosis and cell viability reduction. In addition, Moutan Cortex Radicis treatment effectively activated the adenosine monophosphate-activated protein kinase signaling pathway; however, a specific inhibitor of AMPK significantly reduced Moutan Cortex Radicis-induced apoptosis. Overall, the results suggest that the apoptotic activity of Moutan Cortex Radicis may be associated with a caspase-dependent cascade through the activation of both extrinsic and intrinsic signaling pathways connected with adenosine monophosphate-activated protein kinase activation, and Moutan Cortex Radicis as an activator of adenosine monophosphate-activated protein kinase could be a prospective application to treat human cancers.

Inhibitory effects on the production of inflammatory mediators and reactive oxygen species by Mori folium in lipopolysaccharide-stimulated macrophages and zebrafish

ABSTRACT Mori folium, the leaf of Morus alba L. (Moraceae), has been traditionally used for various medicinal purposes from ancient times to the present. In this study, we examined the effects of water extract of Mori folium (WEMF) on the production of inflammatory mediators, such as nitric oxide (NO) and prostaglandin E2 (PGE2), and reactive oxygen species (ROS) in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages. Our data indicated that WEMF significantly suppressed the secretion of NO and PGE2 in RAW 264.7 macrophages without any significant cytotoxicity. The protective effects were accompanied by a marked reduction in their regulatory gene expression at the transcription level. WEMF attenuated LPS-induced intracellular ROS production in RAW 264.7 macrophages. It inhibited the nuclear translocation of the nuclear factor-kappa B p65 subunit and the activation of mitogen-activated protein kinases in LPS-treated RAW 264.7 macrophages. Furthermore, WEMF reduced LPS-induced NO production and ROS accumulation in zebrafish. Although more efforts are needed to fully understand the critical role of WEMF in the inhibition of inflammation, the findings of the present study may provide insights into the approaches for Mori folium as a potential therapeutic agent for inflammatory and antioxidant disorders.