(+)‑Usnic acid modulates the Nrf2‑ARE pathway in FaDu hypopharyngeal carcinoma cells
- Author:
- Krajka‑Kuźniak V., Paluszczak J., Kleszcz R. & Baer‑Dubowska W.
- Year:
- 2021
- Journal:
- Molecular and Cellular Biochemistry
- Pages:
- 476: 2539–2549
- Url:
- https://doi.org/10.1007/s11010-021-04092-7
Naturally occurring phytochemicals of different origin and structure, arctigenin, bergenin, usnic acid and xanthohumol,
were shown to affect Nrf2 pathway in the context of various diseases, but their effect on this pathway in cancer cells was not
extensively investigated. This study aimed to evaluate the effect of these compounds on Nrf2 expression and activation in
hypopharyngeal FaDu squamous cell carcinoma cells. FaDu cells were treated with 2 or 10 μM arctigenin, bergenin, (+)-
usnic acid or xanthohumol for 24 h. While arctigenin, bergenin, and xanthohumol did not affect either Nrf2 expression or
activation, (+)-usnic acid treatment increased its transcript level and increased the nuclear/cytosol Nrf2 protein ratio—the
measure of Nrf2 pathway activation. Consequently, (+)-usnic acid enhanced the transcription and translation of Nrf2 target
genes: NQO1, SOD, and to a lesser extent, GSTP. The treatment of FaDu cells with (+)-usnic acid decreased both GSK-3β
transcript and protein level, indicating its possible involvement in Nrf2 activation. All the tested compounds decreased Bax
mRNA but did not change the level of Bax protein. (+)-Usnic acid tended to increase the percentage of early apoptotic cells
and LC3 protein, autophagy marker. Significant induction of p53 also was observed after treatment with (+)-usnic acid. In
summary, the results of this study indicate that low concentrations of (+)-usnic acid activate Nrf2 transcription factor, most
probably as a result of ROS accumulation, but do not lead to FaDu hypopharyngeal carcinoma cells death.
Keywords: FaDu cells · Nrf2 · (+)-usnic acid · Arctigenin · Bergenin · Xanthohumol.
- Id:
- 33489
- Submitter:
- zdenek
- Post_time:
- Wednesday, 26 May 2021 17:15