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Ochratoxin A (OTA) is a ubiquitous mycotoxin with potential nephrotoxic, hepatotoxic and immunotoxic effects. The mechanisms underlying the nephrotoxicity of OTA remain obscure. To investigate DNA damage and the changes of the cell cycle distribution induced by OTA, human embryonic kidney cells (HEK 293 cells) were incubated with various concentrations of OTA for 24 h in vitro . The results indicated that OTA treatment led to the production of reactive oxygen species (ROS) and to a decrease of the mitochondrial membrane potential (Δ Ψ m ). OTA-induced DNA damage in HEK 293 cells was evidenced by DNA comet tails formation and increased expression of γ-H2AX. In addition, OTA could induce cell cycle arrest at the S phase in HEK 293 cells. The expression of key cell cycle regulatory factors that were critical to the S phase, including cyclin A2, cyclin E1, and CDK2, were further detected. The expression of cyclin A2, cyclin E1, and CDK2 were significantly decreased by OTA treatment at both the mRNA and protein levels. The apoptosis of HEK 293 cells after OTA treatment was observed using Hoechst 33342 staining. The results confirmed that OTA did induce apoptosis in HEK 293 cells. In conclusion, our results provided new insights into the molecular mechanisms by which OTA might promote nephrotoxicity. [ABSTRACT FROM AUTHOR]

Abstract: This study investigates the anticancer properties of cannabisin B, purified from hempseed hull, in HepG2 human hepatoblastoma cells. The results indicate that cannabisin B significantly inhibited cell proliferation by inducing autophagic cell death rather than typical apoptosis. Cell viability transiently increased upon the addition of a low concentration of cannabisin B but decreased upon the addition of high concentrations. Cannabisin B-induced changes in cell viability were completely inhibited by pre-treatment with 3-methyladenine (3-MA), indicating that the induction of autophagy by cannabisin B caused cell death. Additionally, cannabisin B induced S phase cell cycle arrest in a dose-dependent manner. Moreover, cannabisin B was found to inhibit survival signaling by blocking the activation of AKT and down-stream targets of the mammalian target of rapamycin (mTOR). These findings suggest that cannabisin B possesses considerable antiproliferative activity and that it may be utilised as a promising chemopreventive agent against hepatoblastoma disease. [Copyright &y& Elsevier]

Abstract: Fermentability and contamination level of wine can be assessed through the detection of viable fermentation-related and spoilage-related microorganisms. Ethidium monoazide in combination with quantitative PCR (EMA-qPCR) has been considered as a promising method to enumerate viable cells. Milling for 80 s by Ø 500-μm glass beads is demonstrated to be optimal for DNA extraction from yeasts, lactic acid bacteria (LAB) and acetic acid bacteria (AAB) in wine to be used as a template for PCR. EMA-qPCR results from experiments using DNA extracted by this method correlate well with the results of a plating assay (R 2 > 0.99), and a PCR efficiency between 96% and 105% was obtained. Moreover, for all of these microorganisms, EMA treatment of pure cultures at a low concentration (10 μg/mL) for 20 min photoactivation resulted in effective differentiation between viable and non-viable cells and had no effect on viable cells. Due to sublethal injury to some cells, underestimation of cell counts was found in most of the wine samples tested using the EMA-qPCR method, and a 40-min incubation in recovery medium could completely offset this error. Our results suggest an optimal glass-bead DNA extraction method and EMA treatment suitable for all of the main microorganisms in wine. The EMA-qPCR method was successfully applied to quantify yeasts, Saccharomyces cerevisiae (S. cerevisiae), LAB, non-Oenococcus oeni LAB (non-O. oeni LAB) and AAB in wine samples. [Copyright &y& Elsevier]

Abstract: Drug seeking, craving, and relapse can be triggered by environmental stimuli that acquire motivational salience through repeated associations with the drug''s effects. Previous studies indicated that the dopamine D3 receptor (Drd3) might be involved in the expression of drug-conditioned responses in rats, and brain-derived neurotrophic factor (BDNF) could modulate Drd3 expression in the nucleus accumbens (NAc). However, the involvement of neural regions with Drd3 activation and the underlying interaction between BDNF and Drd3 in the expression of behavioral responses controlled by a drug-associated environment have remained poorly understood. The present study used a conditioning procedure to assess the roles of BDNF, Drd3, and their interactions in the NAc in the expression of morphine-induced context-specific locomotor sensitization. We showed that the expression of locomotor sensitization in the morphine-paired environment was accompanied by significantly increased expression of Drd3 mRNA and BDNF mRNA and protein levels. Both sensitized locomotion in morphine-paired rats and enhanced Drd3 mRNA were suppressed by intra-NAc infusion of anti-tyrosine kinase receptor B (TrkB) IgG. Furthermore, intra-NAc infusion of the Drd3-selective antagonist SB-277011A significantly decreased the expression of context-specific locomotor sensitization and upregulated BDNF mRNA. Altogether, these results suggest that BDNF/TrkB signaling and activation of Drd3 in the NAc are required for the expression of morphine-induced context-specific locomotor sensitization. [Copyright &y& Elsevier]

Abstract: Plant virus-induced gene silencing (VIGS) is currently a powerful tool for the study of gene function in plants. Here we report the silencing of LeACS2 by vacuum-infiltration and the tobacco rattle virus (TRV)-based VIGS method, which leads to a significant delay of the postharvest ripening and senescence of tomato fruit. Harvested mature green tomato fruit were vacuum-infiltrated with Agrobacterium strain GV3101 containing pTRV1 and pTRV2-LeACS2. Because of the silencing of LeACS2, the ethylene climacteric and pigment changes were clearly delayed. The onset of fruit ripening and senescence was significantly postponed, and transcription of LeACS2 and ACC synthase activity were also suppressed in treated tomato fruit during storage. The silencing of LeACS2 by vacuum infiltration, however, did not alter the contents assayed at the end of storage. Our results indicate that vacuum infiltration is a highly efficient TRV-based VIGS method to silence LeACS2 in harvested tomato fruit. It can obviously delay ripening and senescence, and is a potential method for postharvest preservation of tomato fruit. [Copyright &y& Elsevier]

• Neuroinflammation induced depressive-like behavior. • Neuroinflammation upregulated the JNK phosphorylation in three brain areas. • Neuroinflammation upregulated the phosphorylation of GR-Ser246. • Inhibition of JNK ameliorated neuroinflammation-induced depressive-like behavior. • Inhibition of JNK reduced neuroinflammation and phosphorylation of GR-Ser246. Depression is associated with immune dysregulation and the aberrant activity of the hypothalamic-pituitary-adrenal (HPA) axis. However, the neurobiological molecular mechanisms underlying these associations remain unclear. c-Jun amino-terminal kinase (JNK), an important modulator in inflammation and stress responses, is often critically implicated in the development of central nervous system diseases. However, whether and how JNK mediates neuroinflammation-induced depression remains largely unknown. In this study, we investigated the role of JNK in depressive-like behaviors induced by central lipopolysaccharide (LPS) infusion. The results showed that LPS infusion led to depressive-like behaviors, accompanied by increased proinflammatory cytokine expression, increased JNK activation, and upregulated glucocorticoid receptor (GR) phosphorylation at serine 246 (pGR-Ser246) in the habenula (Hb), amygdala (Amyg) and medial prefrontal cortex (mPFC). Treatment with SP600125, a known JNK inhibitor, prevented the LPS-induced hyper-activation of JNK and alleviated depressive-like behaviors. Moreover, LPS-induced increases in the expression levels of TNF-α, IL-1β and pGR-Ser246 in these brain regions were reduced when the rats were treated with SP600125. Our results show, for the first time, that JNK activities in the Hb, Amyg, and mPFC are involved in the modulation of neuroinflammation-induced depression and participate in the regulation of the expression of proinflammatory cytokines and GR phosphorylation, which are pathological factors associated with depression. Our findings provide new insights into the mechanism of neuroinflammation-associated depression and suggest that the JNK pathway may be a potential target for treating inflammation-related depression. [ABSTRACT FROM AUTHOR]