Fraxetin Induces Heme Oxygenase-1 Expression by Activation of Akt/Nrf2 or AMP-activated Protein Kinase α/Nrf2 Pathway in HaCaT Cells.
10.15430/JCP.2016.21.3.135
- Author:
Juthika KUNDU
1
;
In Gyeong CHAE
;
Kyung Soo CHUN
Author Information
1. College of Pharmacy, Keimyung University, Daegu, Korea. chunks@kmu.ac.kr
- Publication Type:Original Article
- Keywords:
Fraxetin;
Keratinocytes;
Heme oxygenase-1;
Nrf2
- MeSH:
AMP-Activated Protein Kinases*;
Blotting, Western;
Carcinogenesis;
Cell Survival;
Heme Oxygenase-1*;
Heme*;
Humans;
Inflammation;
Keratinocytes;
Neuroprotective Agents;
Phosphorylation;
Reactive Oxygen Species;
RNA, Messenger
- From:Journal of Cancer Prevention
2016;21(3):135-143
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND: Fraxetin (7,8-dihydroxy-6-methoxy coumarin), a coumarin derivative, has been reported to possess antioxidative, anti-inflammatory and neuroprotective effects. A number of recent observations suggest that the induction of heme oxygenase-1 (HO-1) inhibits inflammation and tumorigenesis. In the present study, we determined the effect of fraxetin on HO-1 expression in HaCaT human keratinocytes and investigated its underlying molecular mechanisms. METHODS: Reverse transcriptase-PCR and Western blot analysis were performed to detect HO-1 mRNA and protein expression, respectively. Cell viability was measured by the MTS test. The induction of intracellular reactive oxygen species (ROS) by fraxetin was evaluated by 2′,7′-dichlorofluorescin diacetate staining. RESULTS: Fraxetin upregulated mRNA and protein expression of HO-1. Incubation with fraxetin induced the localization of nuclear factor-erythroid-2-related factor-2 (Nrf2) in the nucleus and increased the antioxidant response element-reporter gene activity. Fraxetin also induced the phosphorylation of Akt and AMP-activated protein kinase (AMPK)α and diminished the expression of phosphatase and tensin homolog, a negative regulator of Akt. Pharmacological inhibition of Akt and AMPKα abrogated fraxetin-induced expression of HO-1 and nuclear localization of Nrf2. Furthermore, fraxetin generated ROS in a concentration-dependent manner. CONCLUSIONS: Fraxetin induces HO-1 expression through activation of Akt/Nrf2 or AMPKα/Nrf2 pathway in HaCaT cells.
