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Nonylphenol (NP), an environmental endocrine disruptor mimics estrogen and is a potential toxicant both under in vitro and in vivo conditions. In this study, the effect of melatonin on NP- induced neurotoxicity and cognitive alteration was investigated in adult male Wistar rats. Melatonin supplementation has been known to protect cells from neurotoxic injury. The animals were divided into three groups namely, control (vehicle) which received olive oil orally and treated rats received NP (25 mg/kg, per os ) thrice a week for 45 days while the third group i.e., NP + melatonin, animals were co-administered melatonin (10 mg/kg, i.p. ) along with NP. On the 46th day, rats were assessed for anxiety, motor co-ordination, grip strength and cognitive performance using Morris water maze test and then sacrificed for biochemical and histopathological assays in brain tissues. Melatonin improved the behavioral performance in NP exposed group. The results showed that NP significantly decreased the activity of acetylcholine esterase (AchE), monoamine oxidase (MAO) and Na + /K + -ATPase, in rat brain tissue along with other enzymes of antioxidant milieu. The outcome of the study shows that NP, like other persistent endocrine disrupting pollutants, creates a potential risk of cognitive, neurochemical and histopathological perturbations as a result of environmental exposure. Taken together, our study demonstrates that melatonin is protective against NP-induced neurotoxicity. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA), a well-known xenoestrogen, is ubiquitously utilized in manufacturing of polycarbonated plastics. Convincing evidence suggests that BPA induces neurotoxicity and certain behavioral deficits. α-Lipoic acid (ALA) supplementation has shown protective effect against heart and liver diseases, diabetes, and neurological debility associated with aging. We studied the neuromodulatory effect of ALA against neurotoxicity of BPA in vitro in C8-D1A mouse astrocyte cell line and in vivo in C57BL/6J male mice. In vitro ALA (100 μM) protected cells from BPA (30 μM)-induced reactive oxygen species generation and increased activity of glial fibrillary acidic protein. ALA showed reduction in cell death in astrocytes treated with BPA. In vivo ALA (50 mg/kg) increased the neurospecific acetylcholinesterase activity and decreased the monoamine oxidase activity altered by BPA exposure (10 mg/kg, per os x 30 days). In addition to neuroprotective effects, ALA also showed protective effects against BPA-induced oxidative stress. We observed that ALA significantly replenished the declined neurobehavioral and cognitive performances, decreased muscle coordination and alerted short-term recognition memory in mice exposed to BPA. Our results suggest that ALA has a promising role in modulating BPA-induced neurotoxicity in C8-D1A mouse astrocyte cells as well as neurochemical and neurobehavioral deficits in C57BL/6J male mice and its antioxidant and free radical scavenging activities may in part be responsible for such an effect. [ABSTRACT FROM AUTHOR]

Ischemic stroke (IS) is a rapidly increasing global burden and is associated with severe neurological decline and mortality. There is urgent requirement of the efforts, aimed to identify therapeutic strategies that are effective in clinic to promote significant recovery from IS. Studies have shown that mitochondria mediated neuroprotection can be a competent target against ischemic damage. Therefore, we examined whether mitochondrial impairment is regulated by Piperine (PIP), an alkaloid of Piper Longum , which has neuroprotective activity against ischemic brain injury. In this study, transient middle cerebral artery occlusion (tMCAO) surgery was performed on male Wistar rats for 90 min followed by 22.5 h of reperfusion for mimicking the IS condition. This study consisted of three groups: sham, tMCAO and tMCAO + PIP (10 mg/kg b.wt., p.o/day for 15 days), and studied for behavioral tests, infarct volume, brain pathological changes, mitochondrial dysfunction, inflammation alongwith cell survival status. PIP pre-treatment showed reduction in neurological alterations and infarct volume. In addition, PIP pre-treatment suppressed the mitochondrial dysfunction and might have anti-apoptotic potential by preventing Cytochrome c (Cyt c) release from mitochondria to cytoplasm and caspase 3 activation. It also regulates pro-apoptotic, Bax and anti-apoptotic, Bcl-2 proteins accompanied by glial fibrillary acidic protein (GFAP) positive cells in cortex region. Quantitative Reverse transcription-polymerase chain reaction (qRT-PCR) results also showed that PIP reduced the expression of pro-inflammatory protein, interleukin-1 β (IL-1β) and enhanced cell survival by restoring the activity of brain derived neurotrophic factor (BDNF) and its transcription protein, cAMP response element binding protein (CREB). Taken together, PIP reduced the mitochondrial dysfunction, neurological impairment, and enhanced neuronal survival. In conclusion, our findings reinforce PIP as an effective neuroprotective agent and provide important evidence about its role as a potential target to serve as a promising therapy for treatment of IS. Schematic representation of mitochondria mediated mechanisms of neuroprotection against ischemic stroke provided by Piperine. Piperine can inhibit mitochondrial dysfunction by suppressing inflammation and mitochondrial ROS mediated alterations in ETC and reduced mitochondrial membrane permeability (Δѱm) thereby preserving mitochondrial Cyt c level through blockage of mitochondrial permeability transition pore (mPTP). Finally, it might increase anti-apoptotic (Bcl-2) protein and decrease pro-apoptotic (Bax) protein, and alleviated neuronal cell death. Piperine also involved in cell survival processes and ultimately rescued neuronal morphological alterations and neurobehavioral abnormalities. IL-1β (Interleukin-1β), GFAP (Glial Fibrillary Acidic Protein), LPO (Lipid Peroxidation), GSH (Glutathione), Cyt c (Cytochrome c), Electron transport chain (ETC), Reactive oxygen species (ROS). [Display omitted] • Ischemic animals pre-treated with piperine showed reduced neurological alterations and infarct volume. • Piperine improved mitochondrial dysfunction. • Piperine showed anti-apoptotic potential by preventing cytochrome c release from mitochondria to cytoplasm. • PIP reduced neurological impairment and enhanced cell survival. [ABSTRACT FROM AUTHOR]