Lactobacillus plantarum KFY02 (LP-KFY02) was isolated from naturally fermented yoghurt in Xinjiang. We previously demonstrated that LP-KFY02 has good biological activity in vitro. In this study, LP-KFY02 was used to ferment grape skin, and the LP-KFY02 fermented grape skin extract
solution (KFSE) was examined for its
antioxidant ability in a human embryonic kidney (293T) cell oxidative damage model caused by H2O2 and its inhibitory effect on human
hepatoma (HepG2) cells. The results showed that KFSE reduced the degree of oxidative damage in 293T cells, increased the relevant expression levels of
superoxide dismutase (SOD),
catalase (CAT),
glutathione (GSH), and GSH-
peroxidase (GSH-Px), and total
antioxidant capacity (T-AOC), and decreased the expression levels of
lactate dehydrogenase (LDH),
malondialdehyde (MDA), and
nitric oxide (NO). The expression of genes and
proteins of SOD, CAT, GSH, and GSH-Px was up-regulated. In addition, KFSE-induced growth inhibition appeared to be through induction of cell-cycle arrest. This induction was accompanied by a reduction in the expression of cell-cycle genes, such as cyclin-D1 and CDK4. In addition, KFSE induced gene expression of p21, the apoptosis gene wild-type p53 and the
caspase family. At the
protein expression level, Bax and
Caspase-8 were up-regulated, and the inflammatory marker
Nuclear Factor Kappa-B (NF-κB) was down-regulated. The fermentation
solution polyphenols were separated and identified as
epicatechin gallate,
coumarin, new
chlorogenic acid,
rutin,
resveratrol,
chlorogenic acid,
rosmarinic acid, etc. by HPLC. Overall, these results demonstrate that KFSE significantly attenuated oxidative damage in 293T cells and inhibited
tumor growth in HepG2
cancer cells, induces cell-cycle arrest and affects
proteins involved in cell-cycle regulation and proliferation. This suggests that KFSE may also be explored as a neo-adjuvant to expansion of
hepatoma.