Inhibitory effects of whisky congeners on IgE-mediated degranulation in rat basophilic leukemia RBL-2H3 cells and passive cutaneous anaphylaxis reaction in mice.

Whisky is matured in oak casks. Many nonvolatile substances (whisky congeners, WC) seep from the oak cask during the maturing process. In this study, three antiallergic agents (syringaldehyde, SA; lyoniresinol, Lyo; and ellagic acid, EA) were isolated from WC. Treatment with SA, Lyo, and EA reduced the elevation of intracellular free Ca(2+) concentration ([Ca(2+)]i) and intracellular ROS production caused by FcepsilonRI activation. The inhibitions of the elevation of [Ca(2+)]i and intracellular ROS production by SA and Lyo were mainly due to the suppression of the NADPH oxidase activity and scavenging of the produced radical, respectively. On the other hand, EA inactivated spleen tyrosine kinase and led to the inhibition of the elevation of [Ca(2+)]i and intracellular ROS production. Furthermore, it was found that WC strongly inhibited IgE binding to the FcepsilonRIalpha chain, whereas SA, Lyo, and EA did not indicate this inhibitory effect. These results suggest that WC inhibits allergic reactions through multiple mechanisms. To disclose the in vivo effects of WC, SA, Lyo, and EA, these compounds were administered to type I allergic model mice, and the passive cutaneous anaphylaxis (PCA) reaction was measured. These compounds remarkably suppressed the PCA reaction. Taken together, these findings suggest that WC seemed to be beneficial to ameliorate allergic reactions.

Ca2+/calmodulin-dependent protein kinase II mediates apoptosis of P19 cells expressing human tau during neural differentiation with retinoic acid treatment.

The involvement of tau phosphorylation in apoptosis resembling Alzheimer's disease (AD) was investigated using a cell model of P19 cells stably expressing human tau441 (tau/P19 cells). Apoptotic cell death was observed specifically in tau/P19 cells during neural differentiation with retinoic acid (RA) treatment. A CaM kinase II inhibitor, KN-93, protected tau/P19 cells from apoptosis, although it stimulated the cell death of wild-type P19 cells (wt/P19 cells). W-7 and calmidazolium, calmodulin antagonists, also specifically inhibited the apoptosis of tau/P19 cells. LiCl, an inhibitor of glycogen synthase 3, a tau kinase, was effective in protecting tau/P19 cells from apoptosis, but the protective effect was less than that of CaM kinase II inhibitor and calmodulin antagonists. Tau in the nuclei of tau/P19 cells was phosphorylated at the sites for CaM kinase II detected by an antibody recognizing a phosphorylated form of tau. These results indicated that CaM kinase II was involved in the apoptosis of tau/P19 cells induced by RA treatment.

Development and specific induction of apoptosis of cultured cell models overexpressing human tau during neural differentiation: Implication in Alzheimer's disease.

Apoptosis or programmed cell death is considered to be involved in neurodegenerative disorders, including Alzheimer's disease (AD). AD is characterized by intracellular aggregates of hyperphosphorylated tau, a microtubule-associated protein. To investigate the induction of apoptosis by abnormal tau resembling AD, cultured cells may be useful tools. We developed a cell culture model and established NG108-15 and P19 cells stably transfected with human tau, naming them tau/NG and tau/P19 cells, respectively. Increased accumulation and phosphorylation of tau were observed during neural differentiation in tau/NG cells. Tau/P19 cells underwent drastic apoptosis during neural differentiation induced by retinoic acid (RA). Tau protein was distributed throughout the cytoplasm and in specific zones of the nucleus. The cytoplasmic tau was associated with microtubules, but the nucleic tau was observed to form clusters and was associated with RA receptor (RAR). The apoptosis induced by RA was inhibited by the treatment of glycogen synthase kinase 3 (GSK3) inhibitor in tau/P19 cells. We propose that translocation of tau into nucleus affects RA signaling in apoptosis via GSK3 in the cells. These cells are useful for monitoring the apoptosis by abundant tau and may be applied to investigate the molecular mechanism of apoptosis resembling AD.

[Analysis of SNPs and enzymatic disorder in the patients of influenza-associated encephalopathy: disorder of fatty acid metabolism in mitochondria induced by high fever].

To assess the etiology of influenza-associated encephalopathy(IAE), a surveillance effort was conducted during 2000-2005 in Japan. Over half of fatal and handicapped IAE patients exhibited a disorder of mitochondrial beta-oxidation and ATP generation evoked by the thermolabile phenotype of carnitine palmitoyltransferase II variations with transiently elevated serum acylcarnitine during high-grade fever. Model mice having impaired mitochondrial beta-oxidation exhibited significant accumulation of mini-plasmin and up-regulation of trypsin in the cerebral capillaries after infection with influenza A virus, resulting in the destruction of blood-brain barrier and increased brain vascular permeability. Trypsin up-regulation was also evident in the neuronal cells in the hippocampus, suggesting a severe neurologic complication of IAE.

Increase in apoptosis with neural differentiation and shortening of the lifespan of P19 cells overexpressing tau.

Apoptosis or programmed cell death is considered to be involved in neurodegenerative disorders including Alzheimer's disease (AD). AD is characterized by intracellular aggregates of hyperphosphorylated tau, a microtubule-associated protein. To investigate the effect of the overexpression of tau in P19 cells, we engineered P19 wild-type cells (P19wt) stably expressing human tau441 (P19tau). When P19tau cells were induced to undergo neural differentiation by treatment with retinoic acid (RA), a remarkable increase in apoptosis was observed. However, in the undifferentiated state, there was no notable difference of phenotype between P19wt and P19tau cells. Additionally, we found that tau dissociated from microtubules, and co-localized with the RA receptor (RAR) at nucleoli. Further, the lifespan of the differentiated P19tau cells was shorter than that of P19wt cells, and the re-treatment of differentiated P19wt cells with RA resulted in a reduction of lifespan. These observations suggested that tau affects RA signaling in apoptosis and lifespan during the neural differentiation induced by RA treatment.

Overexpression of tau leads to the stimulation of neurite outgrowth, the activation of caspase 3 activity, and accumulation and phosphorylation of tau in neuroblastoma cells on cAMP treatment.

To explore changes to the tau molecule in Alzheimer's disease, we studied the effect of tau expression in stably transfected neuroblastoma x glioma hybrid NG108-15 cells (tau cells). Tau cells had a similar shape to, but more neurites than, wild type NG108-15 cells (wild type cells). When treated with cAMP, tau cells began to form neurites within 2h. After that, these neurites became longer and thicker than those of wild type cells. An accumulation and increased phosphorylation of tau were observed after 8 h and caspase 3 activity was increased after 4 h in tau cells, but not in wild type cells, upon treatment with cAMP. Caspase 3 activity was activated after the initiation of morphological change, and before the accumulation of tau in tau cells. Under these conditions, apoptotic cell death was not observed and tau was colocalized with tubulin. However, the accumulated tau molecules did not associate with tubulin and were dislocated around and in the nuclei of tau cells. These observations have implications for the cellular causes of Alzheimer's disease where the accumulation and mislocation of tau occur concomitant with neuronal degeneration.