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1. The aim of this study was to investigate the inhibitory effect of morusin on Glucuronosyltransferase (UGT) isoforms and cytochrome P450 enzymes (CYP450s). We also investigated the metabolism of morusin in human, rat, dog, monkey, and minipig liver microsomes. 2. 100 μM of morusin exhibited strong inhibition on all UGTs and CYP450s. The half inhibition concentration (IC50) values for CYP3A4, CYP1A2, CYP2C9, CYP2E1, UGT1A6, UGT1A7, and UGT1A8 were 2.13, 1.27, 3.18, 9.28, 4.23, 0.98, and 3.00 μM, and the inhibition kinetic parameters (Ki) were 1.34, 1.16, 2.98, 6.23, 4.09, 0.62, and 2.11 μM, respectively. 3. Metabolism of morusin exhibited significant species differences. The quantities ofM1from minipig, monkey, dog, and rat were 7.8, 11.9, 2.0, and 6.3-fold of human levels. TheKmvalues in HLMs, RLMs, MLMs, DLMs, and PLMs were 7.84, 22.77, 14.32, 9.13, and 22.83 μM, andVmaxfor these species were 0.09, 1.23, 1.43, 0.15, and 0.75 nmol/min/mg, respectively. CLint(intrinsic clearance) values (Vmax/Km) for morusin obeyed the following order: monkey > rat > minipig > dog > human. CLH(hepatic clearance) values for humans, dogs, and rats were calculated to be 8.28, 17.38, and 35.12 mL/min/kg body weight, respectively. 4. This study provided vital information to understand the inhibitory potential and metabolic behavior of morusin among various species. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Increased VGSCs and CaM but decreased CaMKII were found in hippocampus. [•] Decreased VGSCs and CaM but increased CaMKII were observed in temporal lobe cortex. [•] VGSC proteins appeared in CA1, CA3 and DG of hippocampus and temporal lobe cortex. [•] Co-localizations of VGSCs and CaM were found in hippocampus and temporal lobe cortex. [Copyright &y& Elsevier]

Abstract: The two critical forms of dementia are Alzheimer''s disease (AD) and vascular dementia (VD). The alterations of Ca2+/calmodulin/CaMKII/CaV1.2 signaling in AD and VD have not been well elucidated. Here we have demonstrated changes in the levels of CaV1.2, calmodulin, p-CaMKII, p-CREB and BDNF proteins by Western blot analysis and the co-localization of p-CaMKII/CaV1.2 by double-labeling immunofluorescence in the hippocampus of APP/PS1 mice and VD gerbils. Additionally, expression of these proteins and intracellular calcium levels were examined in cultured neurons treated with Aβ1–42. The expression of CaV1.2 protein was increased in VD gerbils and in cultured neurons but decreased in APP/PS1 mice; the expression of calmodulin protein was increased in APP/PS1 mice and VD gerbils; levels of p-CaMKII, p-CREB and BDNF proteins were decreased in AD and VD models. The number of neurons in which p-CaMKII and CaV1.2 were co-localized, was decreased in the CA1 and CA3 regions in two models. Intracellular calcium was increased in the cultured neurons treated with Aβ1–42. Collectively, our results suggest that the alterations in CaV1.2, calmodulin, p-CaMKII, p-CREB and BDNF can be reflective of an involvement in the impairment in memory and cognition in AD and VD models. [Copyright &y& Elsevier]

Abstract: Impaired GABAergic inhibitory neurotransmission plays an essential role in the pathogenesis of epilepsy. GABAA receptor (GABAAR), potassium chloride cotransporter 2 (KCC2) and astrocytes are of particular importance to GABAergic transmission and thus involved in the development of increased seizure susceptibility. The tremor rat (TRM: tm/tm), a genetic mutant discovered in a Kyoto–Wistar colony, can manifest both absence-like seizures and tonic convulsions without any external stimuli. So far, there are no reports that can elucidate the effects of GABAAR (α4, γ2 subunit), KCC2 and astrocytes on TRMs. The present study was undertaken to detect the expressions of GABAAR α4, GABAAR γ2 and KCC2 in TRMs hippocampus at mRNA and protein levels. In this work, mRNA and protein expressions of GABAAR α4 were significantly elevated while GABAAR γ2 and KCC2 were both evidently decreased in TRMs hippocampus by real-time RT-PCR and western blot, respectively. Furthermore, a dramatic elevation of KCC2 protein level was found after cerebroventricular injection with K252a to TRMs than that in the DMSO-treated TRMs. Besides, our present study also demonstrated that GFAP (a major component of astrocyte) immunoreactivity was much more intense in TRMs hippocampal CA1, CA3 and DG regions than that in control group with immnohistochemistry and confocal microscopic analyses. The protein expression of GFAP was also markedly elevated in TRMs hippocampus, suggesting that astrogliosis appeared in the TRM model. These data demonstrate that altered expressions of GABAAR (α4, γ2) and KCC2 and astrogliosis observed in TRMs hippocampus may provide us good therapeutic targets for the treatment of genetic epilepsy. [Copyright &y& Elsevier]

Abstract: The loss of GABAergic neurotransmission has been closely linked with epileptogenesis. The modulation of the synaptic activity occurs both via the removal of GABA from the synaptic cleft and by GABA transporters (GATs) and by modulation of GABA receptors. The tremor rat (TRM; tm/tm) is the parent strain of the spontaneously epileptic rat (SER; zi/zi, tm/tm), which exhibits absence-like seizure after 8 weeks of age. However, there are no reports that can elucidate the effects of GATs and GABAA receptors (GABARs) on TRMs. The present study was conducted to detect GATs and GABAR α1 subunit in TRMs hippocampus at mRNA and protein levels. In this study, total synaptosomal GABA content was significantly decreased in TRMs hippocampus compared with control Wistar rats by high performance liquid chromatography (HPLC); mRNA and protein expressions of GAT-1, GAT-3 and GABAR α1 subunit were all significantly increased in TRMs hippocampus by real time PCR and Western blot, respectively; GAT-1 and GABAR α1 subunit proteins were localized widely in TRMs and control rats hippocampus including CA1, CA3 and dentate gyrus (DG) regions whereas only a wide distribution of GAT-3 was observed in CA1 region by immunohistochemistry. These data demonstrate that excessive expressions of GAT-1 as well as GAT-3 and GABAR α1 subunit in TRMs hippocampus may provide the potential therapeutic targets for genetic epilepsy. [Copyright &y& Elsevier]