Abstract Title:

Modulation of the Nrf2 signalling pathway in Hct116 colon carcinoma cells by baicalein and its methylated derivative negletein.

Abstract Source:

Pharm Biol. 2016 May 4:1-12. Epub 2016 May 4. PMID: 27143122

Abstract Author(s):

Susannah Havermann, Yvonni Chovolou, Hans-Ulrich Humpf, Wim Wätjen

Article Affiliation:

Susannah Havermann


CONTEXT: Baicalein is a major compound in extracts derived from Scutellaria baicalensis Georgi (Lamiaceae) which are used in the Traditional Chinese Medicine for the treatment of inflammatory and gastrointestinal diseases. This flavonoid is an activator of the Nrf2 signalling pathway but the molecular mechanism is not clearly established.

OBJECTIVE: We investigated the molecular mode of baicalein-mediated Nrf2-activation in Hct116 cells by the analysis of proteasomal activity, radical-scavenging activity and the comparison with baicalein derivatives.

MATERIALS AND METHODS: The radical-scavenging activity (TEAC, DCF) up to 25 μM, cytotoxicity (MTT assay, 48 h) up to 100 μM, proteasomal activity and the Nrf2-activation (luciferase assay, ubiquitinylation, western blot, Ser40-phosphorylation; incubation for 1 or 4 h) by concentrations up to 40 or 50 μM of the compounds were analysed in Hct116 human colon carcinoma cells.

RESULTS: No change in the ubiquitinylation of Nrf2, proteasomal activity and transcription of the NRF2 gene were detectable. Baicalein decreased the phosphorylation of Nrf2 (IC50-value approximately 20 μM) suggesting an inhibitory effect of the flavonoid on protein kinases. Since the activation of the Nrf2 pathway by baicalein might be also due to redox-activity of the compound, we investigated the effects of methylated baicalein derivatives oroxylin A, negeletein and baicaleintrimethylether.Oroxylin A and negletein showed a comparable redox-active potential, but only negletein (50 μM, 4 h) was able to activate Nrf2.

CONCLUSION: This result confirms the hypothesis that baicalein, a component of extracts derived from Baical Skullcap, causes an activation of Nrf2 independent of a modulation of the cellular redox potential.

Study Type : In Vitro Study

Print Options

Key Research Topics

Sayer Ji
Founder of GreenMedInfo.com

Subscribe to our informative Newsletter & get Nature's Evidence-Based Pharmacy

Our newsletter serves 500,000 with essential news, research & healthy tips, daily.

Download Now

500+ pages of Natural Medicine Alternatives and Information.

This website is for information purposes only. By providing the information contained herein we are not diagnosing, treating, curing, mitigating, or preventing any type of disease or medical condition. Before beginning any type of natural, integrative or conventional treatment regimen, it is advisable to seek the advice of a licensed healthcare professional.

© Copyright 2008-2022 GreenMedInfo.com, Journal Articles copyright of original owners, MeSH copyright NLM.