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Diclofenac, a widely used non-steroidal anti-inflammatory drug, can cause liver damage via its metabolic activation by hepatic CYP450s and UGT2B7. Fasting can affect drug-induced liver injury by modulating the hepatic metabolism, but its influence on diclofenac hepatotoxicity is unknown. Thus, we investigated diclofenac-induced liver damage after fasting in mice, and the cellular events were examined. Male ICR mice fasted for 16 h showed the elevation of CYP3A11, but the decreases of UGT2B7, glutathione (GSH), and GSH S-transferase-μ/-π levels in the livers. Diclofenac (200 mg/kg) injection into the mice after 16-h fasting caused more significant liver damage compared to that in the diclofenac-treated fed mice, as shown by the higher serum ALT and AST activities. Diclofenac-promoted hepatic oxidative stress (oxidized proteins, 4-hydroxynonenal, and malondialdehyde), endoplasmic reticulum (ER) stress (BiP, ATF6, and CHOP), and apoptosis (cleaved caspase-3 and cleaved PARP) were enhanced by fasting. Autophagic degradation was inhibited in the diclofenac-treated fasting mice compared to that of the corresponding fed mice. The results suggest that fasting can make the liver more susceptible to diclofenac toxicity by lowering GSH-mediated detoxification; increased oxidative/ER stresses and apoptosis and suppressed autophagic degradation may be the cellular mechanisms of the aggravated diclofenac hepatotoxicity under fasting conditions. [Display omitted] • Fasting potentiated diclofenac-induced liver injury in mice. • Fasting increased diclofenac-promoted oxidative stress, ER stress, and apoptosis. • Fasting aggravated diclofenac-induced suppression of autophagic degradation. • Fasting increased hepatic CYP3A11, but decreased GSH and GST levels. • Fasting decreased GSH-mediated diclofenac detoxification. [ABSTRACT FROM AUTHOR]

Dibutyl phthalate (DBP) is commonly used plasticizer and a known endocrine disruptor that can cause birth defects and developmental disorders. Although several studies have reported that DBP has neurotoxic effects on neurite outgrowth and on learning and memory, its neurotoxic effects on neural progenitor cells (NPCs) have not been investigated. The present study was undertaken to determine the effects of DBP on NPCs and hippocampal neurogenesis. At high concentration DBP (500 μM) retarded NPC proliferation without affecting cell viability by arresting the cell cycle at G1 but did not cause cell death. DNA damage was observed by examining p53 expression and by γH2AX staining. DBP-treated cells had elevated ROS levels and exhibited mitochondrial dysfunction, which can cause DNA damage. Adult hippocampal neurogenesis was investigated using BrdU immunohistochemistry in young C57BL/6 mice intraperitoneally administrated with vehicle or DBP (10 or 50 mg/kg) for 2 weeks. DBP administered mice were found to have significantly fewer newly generated neurons in hippocampi, and the Morris water maze test revealed that DBP (50 mg/kg) impaired spatial learning and memory. Taken together, these findings suggest that DBP has harmful effects on NPCs and hippocampal neurogenesis and that DBP exposure could lead to learning and memory dysfunctions. • DBP caused cell cycle arrest without cell death. • DBP-induced DNA damage and mitochondrial dysfunction are associated with oxidative stress. • DBP impaired hippocampal neurogenesis. • DBP had adverse effects on the hippocampus-dependent learning and memory. [ABSTRACT FROM AUTHOR]

Chronic exposure to cadmium (Cd) causes remarkable damage to the kidneys, a target organ of accumulated Cd after oral administration. The aim of the present study was to investigate the protective effect of curcumin against Cd-induced nephrotoxicity. Sprague–Dawley male rats were divided into the following four treatment groups: control, curcumin (50 mg/kg, oral), CdCl 2 , (25 mg/kg, oral), and pre-treatment with curcumin (50 mg/kg) 1 h prior to the administration of CdCl 2 (25 mg/kg, oral) for 7 days. At 24 h after the final treatment, the animals were killed, and the biomarkers associated with nephrotoxicity were measured. Our data indicated that blood urea nitrogen (BUN) and serum creatinine (sCr) levels were significantly reduced by curcumin pre-treatment in CdCl 2 -treated animals. Histopathological studies showed hydropic swelling and hypertrophy of the proximal tubular cells in the renal cortex after Cd treatment. Pretreatment with curcumin ameliorated the histological alterations induced by Cd. The urinary excretion of kidney injury molecule-1 (Kim-1), osteopontin (OPN), tissue inhibitor of metalloproteinases 1 (TIMP-1), neutrophil gelatinase-associated lipocalin (NGAL), and netrin-1 significantly reduced by curcumin treatment compared to that in the CdCl 2 -treated group. The administration of curcumin provided a significant protective effect against Cd-induced nephrotoxicity. [ABSTRACT FROM AUTHOR]

Tetrabromobisphenol A (TBBPA) is a brominated flame retardant that is commonly used in commercial and household products, such as, computers, televisions, mobile phones, and electronic boards. TBBPA can accumulate in human body fluids, and it has been reported that TBBPA possesses endocrine disruptive activity. However, the neurotoxic effect of TBBPA on hippocampal neurogenesis has not yet been investigated. Accordingly, the present study was undertaken to evaluate the effect of TBBPA on adult hippocampal neurogenesis and cognitive function. Male C57BL/6 mice were orally administrated vehicle or TBBPA (20 mg/kg, 100 mg/kg, or 500 mg/kg daily) for two weeks. TBBPA was observed to significantly and dose-dependently reduce the survival of newly generated cells in the hippocampus but not to affect the proliferation of newly generated cells. Numbers of hippocampal BrdU and NeuN positive cells were dose-dependently reduced by TBBPA, indicating impaired neurogenesis in the hippocampus. Interestingly, glial activation without neuronal death was observed in hippocampi exposed to TBBPA. Furthermore, memory retention was found to be adversely affected by TBBPA exposure by a mechanism involving suppression of the BDNF-CREB signaling pathway. The study suggests high dose TBBPA disrupts hippocampal neurogenesis and induces associated memory deficits. [ABSTRACT FROM AUTHOR]

Abstract: Bisphenol A (BPA) is widely used in the manufacture of plastics and epoxy resins, and is known to affect reproductive organ growth and development. However, the effects of BPA on hippocampal neurogenesis are unclear in young adult mice. Therefore, the present study was conducted to examine the effects of BPA on hippocampal neurogenesis and learning as well as memory performance in young adult mice. BPA (1, 5, and 20mg/kg/day) was administered orally to mice for 2weeks. It was found that high-dose BPA (20mg/kg/day) decreased the number of newly generated cells in hippocampus, but that low-dose BPA (1mg/kg) increased the survival of newly generated cells in hippocampi of young mice. Furthermore, high-dose BPA (20mg/kg/day) was found to impair learning and memory performance significantly. However, no significant differences were observed between high- and low-dose treated mice in terms of levels of brain-derived neurotrophic factor (BDNF) or reactive oxygen species production in hippocampus. In addition, BPA treatment did not induce neuronal loss or damage or astrocyte activation. These data suggest that exposure to BPA causes fluctuations in hippocampal neurogenesis in young adult mice that result in spatial learning and memory impairment via a BDNF-independent pathway. [Copyright &y& Elsevier]