Docosahexaenoic acid inhibits 12- O -tetradecanoylphorbol-13- acetate-induced fascin-1-dependent breast cancer cell migration by suppressing the PKCδ- and Wnt-1/β-catenin-mediated pathways

Epigallocatechin-3-gallate (EGCG) is the most abundant polyphenol in green tea. To investigate the effects of dietary EGCG on oxidative stress and the metabolism and toxicity of acetaminophen in the liver, rats were fed diets with (0.54%) or without EGCG supplementation for four weeks and were then injected intraperitoneally with acetaminophen (1 g/kg). The results showed that EGCG lowered hepatic oxidative stress and cytochrome P450 (CYP) 1A2, 2E1, and 3A, and UDP-glucurosyltransferase activities prior to acetaminophen injection. After acetaminophen challenge, the elevations in plasma alanine aminotransferase activity and histological changes in the liver were ameliorated by EGCG treatment. EGCG reduced acetaminophen-induced apoptosis by lowering the Bax/Bcl2 ratio in the liver. EGCG mildly increased autophagy by increasing the LC3B II/I ratio. Lower hepatic acetaminophen–glutathione and acetaminophen–protein adducts contents were observed after EGCG treatment. EGCG increased glutathione peroxidase and NAD(P)H quinone 1 oxidoreductase activities and reduced organic anion-transporting polypeptides 1a1 expression in the liver after acetaminophen treatment. Our results indicate that EGCG may reduce oxidative stress and lower the metabolism and toxicity of acetaminophen. The reductions in CYP-mediated acetaminophen bioactivation and uptake transporter, as well as enhanced antioxidant enzyme activity, may limit the accumulation of toxic products in the liver and thus lower hepatotoxicity.

Spinocerebellar ataxia type 3 (SCA3), caused by the abnormal expansion of polyglutamine (polyQ) in the ataxin-3 protein, is one of the inherited polyQ neurodegenerative diseases that share similar genetic and molecular features. Mutant polyQ-expanded ataxin-3 protein is prone to aggregation in affected neurons and is predominantly degraded by autophagy, which is beneficial for neurodegenerative disease treatment. Not only does mutant polyQ-expanded ataxin-3 increase susceptibility to oxidative cytotoxicity, but it also hampers antioxidant potency in neuronal cells. Nuclear factor erythroid-derived 2-like 2 (Nrf2), a master transcription factor that controls antioxidant and detoxification gene expression, plays a crucial role in neuroprotection in SCA3 and other neurodegenerative diseases. The present data showed that treatment with erinacine A-enriched Hericium erinaceus mycelium ethanol extract (HEME) extended longevity and improved locomotor activity in ELAV-SCA3tr-Q78 transgenic Drosophila. Moreover, HEME treatment enhanced antioxidant potency and autophagy, which, in turn, corrected levels of mutant polyQ-expanded ataxin-3 and restrained protein aggregation in both cell and Drosophila models of SCA3. Markedly, HEME increased the activation of Nrf2. Silencing Nrf2 protein expression negated most of the promising effects of HEME on SK-N-SH-MJD78 cells, highlighting the critical role of increased Nrf2 activation in the efficacy of HEME treatment. These findings suggest that HEME has therapeutic potential in SCA3 by enhancing autophagic and Nrf2-mediated antioxidant pathways, which may also influence neurodegenerative progression in other polyQ diseases.