Angiotensin II–Induced MMP-2 Activity and MMP-14 and Basigin Protein Expression Are Mediated via the Angiotensin II Receptor Type 1–Mitogen-Activated Protein Kinase 1 Pathway in Retinal Pigment Epithelium

Platyphyllenone is a type of diarylheptanoid that exhibits anti-inflammatory and chemoprotective effects. However, its effect on oral cancer remains unclear. In this study, we investigated whether platyphyllenone can promote apoptosis and autophagy in SCC-9 and SCC-47 cells. We found that it dose-dependently promoted the cleavage of PARP; caspase-3, -8, and -9 protein expression; and also led to cell cycle arrest at the G2/M phase. Platyphyllenone up-regulated LC3-II and p62 protein expression in both SCC-9 and SCC-47 cell lines, implying that it can induce autophagy. Furthermore, the results demonstrated that platyphyllenone significantly decreased p-AKT and increased p-JNK1/2 mitogen-activated protein kinase (MAPK) signaling pathway in a dose-dependent manner. The specific inhibitors of p-JNK1/2 also reduced platyphyllenone-induced cleavage of PARP, caspase-3, and caspase -8, LC3-II and p62 protein expression. These findings are the first to demonstrate that platyphyllenone can induce both autophagy and apoptosis in oral cancers, and it is expected to provide a therapeutic option as a chemopreventive agent against oral cancer proliferation.

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Activation of signaling pathways and regulatory mechanisms of mRNA translation following myocardial ischemia-reperfusion

Journal of Applied Physiology ◽

10.1152/japplphysiol.01122.2005 ◽

2006 ◽

Vol 101 (2) ◽

pp. 576-582 ◽

Cited By ~ 14

Author(s):

Stephen J. Crozier ◽

Xueqian Zhang ◽

Jufang Wang ◽

Joseph Cheung ◽

Scot R. Kimball ◽

...

Keyword(s):

Protein Kinase ◽

Myocardial Ischemia ◽

Protein Expression ◽

Signaling Pathways ◽

Mrna Translation ◽

Mitogen Activated Protein Kinase ◽

Regulatory Mechanisms ◽

Ischemia And Reperfusion ◽

Myocardial Ischemia And Reperfusion ◽

Mitogen Activated Protein

Protein expression in the heart is altered following periods of myocardial ischemia. The changes in protein expression are associated with increased cell size that can be maladaptive. There is little information regarding the regulation of protein expression through the process of mRNA translation during ischemia and reperfusion in the heart. Therefore, the purpose of this study was to identify changes in signaling pathways and downstream regulatory mechanisms of mRNA translation in an in vivo model of myocardial ischemia and reperfusion. Hearts were collected from rats whose left main coronary arteries had either been occluded for 25 min or reversibly occluded for 25 min and subsequently reperfused for 15 min. Following reperfusion, both the phosphoinositide 3-kinase and mitogen-activated protein kinase pathways were activated, as evidenced by increased phosphorylation of Akt (PKB), extracellular signal-regulated kinase 1/2, and p38 mitogen-activated protein kinase. Activation of Akt stimulated signaling through the protein kinase mammalian target of rapamycin, as evidenced by increased phosphorylation of two of its effectors, the ribosomal protein S6 kinase and the eukaryotic initiation factor eIF4E binding protein 1. Ischemia and reperfusion also resulted in increased phosphorylation of eIF2 and eIF2B. These changes in protein phosphorylation suggest that control of mRNA translation following ischemia and reperfusion is modulated through a number of signaling pathways and regulatory mechanisms.

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