Colored Potato Extracts Induce Superoxide Dismutase-2 mRNA Via ERK1/2 Pathway in HepG2 Cells

Abstract

Rats fed a diet containing Shadow Queen (SQ), an anthocyanin-rich potato cultivar, previously showed an increase in the hepatic superoxide dismutase (SOD)-2 mRNA level. We investigated whether an extract of SQ would directly increase the hepatic SOD-2 mRNA level in HepG2 cells. Furthermore, we estimated the intracellular signaling pathway for the induction of SOD-2 mRNA expression. HepG2 cells were stimulated using extracts of four crops, including SQ, for 12 h; only extracts of colored potatoes induced SOD-2 mRNA expression significantly. This induction of SOD-2 mRNA expression was blocked by an inhibitor of the extracellular signal-related kinase (ERK) 1/2 pathway. Furthermore, an extract of SQ increased the phosphorylation of ERK1/2 after 15 or 30 min of stimulation. These data indicate that an extract of SQ directly induces hepatic SOD-2 mRNA expression via activation of ERK1/2 pathway in HepG2 cells.

Black Soybean Seed Coat Extract Prevents Hydrogen Peroxide-Mediated Cell Death via Extracellular Signal-Related Kinase Signalling in HepG2 Cells

“…In a preliminary study, however, an anthocyanin-rich fraction separated from BE by a column chromatography was assayed with a cell viability test to determine the influence of the diluent on the antioxidant system, and we found the anthocyanin-rich fraction effective (data not shown). These data did not contradict those of our previous studies (3,16). Meanwhile, contents and compositions of anthocyanins and PACs in BE will differ depending on year, area, race, and other factors, suggesting that repeatability and reproducibility should be assessed in further studies.…”

“…These results suggest that PPs were induced by BE treatment within 1 h in HepG2 cells. In our previous study, an anthocyanin fraction from purple potato activated ERK within 15 min in HepG2 cells (16). Although PPs are known to silence MAPK signalling, activated ERK reportedly induces and activates PPs (13,24).…”

“…In our previous studies, anthocyanin fractions from coloured potatoes induced superoxide dismutase-2 mRNA expression via the ERK 1/2 pathway in HepG2 human hepatoma cells (16), and in other studies, flakes of coloured potatoes prevented hepatic injury following galactosamine injections (3). However, the mechanisms by which black soybean seed coat extract (BE) defends against hepatic injury remain poorly characterised.…”

Fermentative quality of purple rice (Oryza sativa L.) silage and its effects on digestibility, ruminal fermentation and oxidative status markers in sheep: A preliminary study

“…In line with the present findings, an increase in antioxidant enzyme without any change in non-enzymatic antioxidant has been reported in sheep fed anthocyanin from anthocyanin-rich corn (Hosoda et al 2012b). However, not all anthocyanin-rich plants and their extracts have a regulating effect on antioxidant enzyme (Hashimoto et al 2010). Therefore, we suggest that, at least, the anthocyanin in purple rice should ameliorate the antioxidative defense in sheep.…”

“…However, not all anthocyanin‐rich plants and their extracts have a regulating effect on antioxidant enzyme (Hashimoto et al . ). Therefore, we suggest that, at least, the anthocyanin in purple rice should ameliorate the antioxidative defense in sheep.…”