Endogenous reactive oxygen species are essential for proliferation of neural stem/progenitor cells.

It is widely thought that accumulation of reactive oxygen species (ROS) causes injury to cells. In this study, we investigated the effect of endogenous ROS on the proliferation of neural stem/progenitor cells derived from the hippocampus of embryonic mice. The cells were treated with free radical-scavenging agents [3-methyl-1-phenyl-2-pyrazolin-5-one (edaravone) or 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (tempol)], an NADPH oxidase inhibitor (apocynin), catalase, a nitric oxide synthase inhibitor [N(omega)-nitro-L-arginine methyl ester hydrochloride (L-NAME)] or a peroxynitrite generator (SIN-1) during the culture period.

Repression of activated aryl hydrocarbon receptor-induced transcriptional activation by 5alpha-dihydrotestosterone in human prostate cancer LNCaP and human breast cancer T47D cells.

Polycyclic aromatic hydrocarbons (PAHs) and dioxins are ubiquitous environmental pollutants and activate the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor. It has been reported that testosterone represses 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced transcription of the cytochrome P450 (CYP) 1A1 gene in LNCaP cells. In this study, we investigated the mechanism for the repression of 3-methylcholanthrene (3MC)-induced transcription of AhR-regulated genes, CYP1A1, CYP1A2, CYP1B1, and AhR repressor (AhRR), by 5alpha-dihydroteststerone (DHT) in LNCaP and T47D cells, which are androgen receptor (AR)- and AhR-positive.

Altered expression of DJ-1 in the hippocampal cells following in vivo and in vitro neuronal damage induced by trimethyltin.

Trimethyltin chloride (TMT) is known to produce neuronal damage in the dentate gyrus at least in part via oxidative stress. DJ-1, an oncogene product, is known to act as an anti-oxidant to prevent neuronal damage in dopaminergic neurons. The aim of this study was to determine the alterations in DJ-1 expression in the hippocampal cells of mice after in vivo and in vitro treatment with TMT.