Related Experiment Videos
Curcumin attenuates ethanol-induced toxicity in HT22 hippocampal cells by activating mitogen-activated protein kinase
Hyun-Ock Pae1, Sun-Oh Jeong, Min Zheng
1Department of Microbiology and Immunology, Wonkwang University School of Medicine, 344-2 Shinyong-dong, Iksan, Jeonbuk 570-749, Republic of Korea.
Abstract:
Ethanol causes neurotoxicity through formation of reactive oxygen species and activation of mitogen-activated protein kinase (MAPK) pathways. MAPK phosphatase-1 (MKP-1) is one of the phosphatases responsible for dephosphorylation/deactivation of MAPKs. In this report, we examined the potential involvement of MKP-1 in cytoprotective effects of the well-known antioxidant curcumin. In HT22 hippocampal cells, ethanol caused cell death and activation of p38 MAPK and other two kinases. Blockage of p38 MAPK by its inhibitor protected HT22 cells against ethanol-induced toxicity. Curcumin attenuated ethanol-induced cell death, inhibited activation of p38 MAPK, and activated MKP-1. In HT22 cells transiently transfected with small interfering RNA against MKP-1, curcumin failed to inhibit ethanol-induced activation of p38 MAPK and to protect HT22 cells from ethanol-induced toxicity. Our results suggest that curcumin can attenuate ethanol-induced neurotoxicity by activating MKP-1 which acts as the negative regulator of p38 MAPK. This novel pathway may contribute to and explain at least one of the cytoprotective actions of curcumin.
Insights
Curcumin protects against ethanol neurotoxicity by activating MAPK phosphatase-1 (MKP-1), which inhibits harmful p38 MAPK pathways. This research reveals a novel cytoprotective mechanism for curcumin.
Area of Science:
- Neuroscience
- Cell Biology
- Pharmacology
Background:
- Ethanol exposure induces neurotoxicity via reactive oxygen species and mitogen-activated protein kinase (MAPK) pathways.
- MAPK phosphatase-1 (MKP-1) is crucial for deactivating MAPKs, but its role in ethanol neurotoxicity is unclear.
Purpose of the Study:
- To investigate the involvement of MKP-1 in the cytoprotective effects of curcumin against ethanol-induced neurotoxicity.
- To elucidate the molecular mechanism by which curcumin exerts its protective effects.
Main Methods:
- Utilized HT22 hippocampal cells exposed to ethanol.
- Assessed cell viability, MAPK activation, and MKP-1 activity.
- Employed p38 MAPK inhibitors and small interfering RNA (siRNA) targeting MKP-1.
Main Results:
- Ethanol induced cell death and activated p38 MAPK; p38 MAPK inhibition offered protection.
- Curcumin reduced ethanol-induced cell death, inhibited p38 MAPK activation, and upregulated MKP-1.
- MKP-1 knockdown abolished curcumin's ability to inhibit p38 MAPK activation and protect cells from ethanol.
Conclusions:
- Curcumin attenuates ethanol neurotoxicity by activating MKP-1, a negative regulator of p38 MAPK.
- This MKP-1-mediated pathway represents a novel mechanism for curcumin's cytoprotective actions.
