Early-Life Exposure to Paraquat Aggravates Sex-Specific and Progressive Abnormal Non-Motor Neurobehavior in Aged Mice.

Early-life exposure to environmental neurotoxicants is known to have lasting effects on organisms. In this study, we aim to investigate the impacts of PQ exposure during early developmental stages and adult re-challenge in aged mice on non-motor neurobehavior. Two mouse models, which were exposed once during early life stage and re-exposure at adulthood, were created to explore the long-term effects of PQ on non-motor neurobehavior.

[Combined cytotoxicity mechanism of chlorpyrifos and carbofuran pesticides in vitro].

Objective: To evaluate the single and combined effects of chlorpyrifos( CPF) and carbofuran( CF) pesticides on cell lines cultured in vitro, and clarify the pattern of joint action.

Methods: Rat pheochromocytoma( PC12 cells) were treated with different concentrations of CPF( 0, 50, 100, 200 and 400 μmol/L) and CF( 0, 25, 50, 100 and 200 μmol/L) for 12 h separately, the combined effects of two kinds of pesticides should be studied respectively in the low dose( CPF 50 μmol/L, CF 25 μmol/L) and high dose( CPF 200 μmol/L, CF 100 μmol/L) levels. After exposure, detectingacetylcholinesterase( ACh E) activity and using fluorescent probe 2', 7'-dichlorfluorescin diacetate( DCFH-DA), thiobarbituric acid( TBA) method, xanthine oxidation, 5, 5 '-dithio-bis-2-nitrobenzoic acid( DTNB) coloration to detect the intracellular reactive oxygen species( ROS) production, lipid peroxidation production malondialdehyde( MDA), activity of antioxidant enzymes superoxide dismutase( SOD) and glutathione peroxidase( GPx), respectively.

Cyclovirobuxine D inhibits the currents of HERG potassium channels stably expressed in HEK293 cells.

Cyclovirobuxine D (CVB-D) has been widely used for treatment of cardiac insufficiency and arrhythmias in China. The antiarrhythmic and proarrhythmic potential of this drug might be concerned with prolongation of action potential duration and QT interval. Human-ether-a-go-go-related gene (HERG) has an important role in the repolarization of the cardiac action potential.

Chlorpyrifos induces delayed cytotoxicity after withdrawal in primary hippocampal neurons through extracellular signal-regulated kinase inhibition.

In this study, the delayed effect and related mechanism after chlorpyrifos (CPF) withdrawal was studied in primary rat hippocampal neurons. The results showed that 10 muM CPF induced no detectable cytotoxicity during 96 h continuous exposure while its withdrawal after 48 h exposure induced evident cytotoxicity, as indexed by decreased methyl thiazolyl tetrazolium (MTT) metabolism, increased loss of neurons immunostained by neuron-specific enolase (NSE) antibody, and the increased terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) positive cell rate in the following 24 h and 48 h incubation in the absence of CPF. Extracellular signal-related kinase (ERK)1/2 activation by phosphorylation was observed and persisted during CPF exposure.

Combined effects of repeated administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin and polychlorinated biphenyls on kidneys of male rats.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) are persistent environmental contaminants that exist as complex mixtures in the environment, but the possible interactions of TCDD and PCBs have not been systematically investigated. The main objective of this study was to investigate the combined nephrotoxic effects of TCDD and PCBs on rats and to reveal the potential interactions between TCDD and PCBs. Male Sprague-Dawley rats were intragastrically administered TCDD (10 microg/kg), PCBs (Aroclor 1254, 10 mg/kg), or the combination (10 microg/kg TCDD + 10 mg/kg Aroclor 1254).