Premium
Induction of Nrf2 Activity by Ethyl Acetate Extract of Lagenaria Breviflora
Author(s) -
Oridupa Olayinka Ayotunde,
Ritchie Kenneth J
Publication year - 2016
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.30.1_supplement.932.5
Subject(s) - luciferase , antioxidant , in vivo , chemistry , glutathione , biochemistry , curcumin , in vitro , cell culture , western blot , transcription factor , pharmacology , biology , gene , enzyme , transfection , microbiology and biotechnology , genetics
The field of cancer chemoprevention is based upon the ability of chemical compounds from any source (synthetic and natural) to prevent cancer. Phytochemicals with the ability to increase the activity of the transcription factor Nrf2 (NF‐E2‐related factor 2) are central to this field. Nrf2 has been reported to modify the expression of up to 200 genes, many of which are involved in cellular defence against toxic insult including heme‐oxygenase 1 (HO‐1), NAD(P)H:quinone oxidoreductase 1 (NQO1) and glutathione S‐transferases (GSTs) [1]. Interestingly many plant species which are known possess direct antioxidant activity through mechanisms such as free radical scavenging have not been investigated for their ability to modify the expression of such crucial cellular defence genes. This study was consequently designed to investigate the Nrf2 induction capability of the medicinal plant Lagenaria breviflora Roberty (LB) which is documented to possess both in vivo and in vitro antioxidant and anti‐inflammatory activities [2]. Nrf2 induction was investigated using the AREc32 cell line, (Nrf2 luciferase assay reporter cell line) and by activation of the Nrf2 regulated gene NQO1 in HepG2 cells by Western blot. Exposure of AREc32 cells to graded concentrations of LB ethyl acetate extract (4mg/ml, 6mg/ml, 8mg/ml and 12mg/ml) significantly increased luciferase activity by 3 – 7.5 fold relative to control. Higher concentrations (8mg/ml and 12mg/ml) were however toxic to the cells (by MTT assay). Kinetic studies revealed significant induction of luciferase activity in AREc32 cells treated with 6mg/ml of the extract for 24 hours (4 fold) and 72 hours (3 fold). LB extract (6mg/ml) also significantly increased the expression of NQO1 protein in HepG2 cells, relative to control, following 24 hour exposure. These results indicate that the ethyl acetate extract of LB contains Nrf2 modulating activity and as such indicates that LB is worthy of further investigation into its potential to act as a cancer chemopreventative agent. Support or Funding Information This research was supported by TETFund Staff Development Grant (Nigeria) Awarded to Dr. Olayinka A. Oridupa