Takeaki Okamoto

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We evaluated the effect of cis-9, trans-11 (9c,11t) and trans-10, cis-12 (10t,12c) conjugated linoleic acid (CLA) on the immune system in C57BL/6J mice. Mice were fed experimental diets containing 0% CLA (controls), 1% 9c,11t-CLA, 1% 10t,12c-CLA or a 1:1 mixture (0.5% + 0.5%) of these two CLA isomers for 3 wk. Relative spleen weights of all CLA fed mice(More)
BACKGROUND Although the importance of monocyte trans-endothelial migration in early atherogenesis is well recognized, it is unclear whether and how one transmigration event affects endothelium to facilitate subsequent ones. In this study, we tested the hypothesis that monocyte transmigration alters endothelial junctional organization to facilitate(More)
Indoleamine 2,3-dioxygenase (IDO; EC is a rate-limiting enzyme involved in the catabolism of tryptophan, which is an essential amino acid. It is induced under pathological conditions, such as the presence of viral infections or tumour cells. This enzyme is induced by IFN-gamma in the mouse rectal carcinoma cell line CMT-93. It is known that both(More)
Alpha-lipoic acid has been shown to possess cancer-cell-killing activity via activation of the apoptosis pathway. In this study, the cytotoxic activities of alpha-lipoic and dihydro-alpha-lipoic acid were compared in HL-60 cells. The cell-killing activity of dihydro-alpha-lipoic acid was higher than that of alpha-lipoic acid. Both alpha-lipoic and(More)
Epidemiological studies have indicated a correlation between homocysteinemia and dementia, including Alzheimer's disease. However, the mechanism by which homocysteine (Hcy) induces neuronal cell death remains unknown. We found that micromolar concentrations of Hcy induced neuroblastoma SH-SY5Y cell death only when co-cultured with glioblastoma U251MG cells.(More)
We previously identified perchloric acid-soluble protein (PSP) in the rat liver, kidney, brain and lung, and reported that it appeared to be related to repression of cell proliferation. In the present study, we clarified that PSP was expressed in the intestine, and found that the amino acid sequence of the intestinal PSP was consistent with those of other(More)
In response to atherogenic stimuli, blood monocytes transmigrate across the vascular endothelium not only through endothelial cell–cell junctions (para-cellular) but also through endothelial cells themselves (trans-cellular). The molecular mechanism of the latter is mostly unknown, because it rarely happens, especially in vitro. Although many reports have(More)
The water-soluble fraction of kale (Brassica oleracea L. var. acephala DC.) had immunoglobulin (Ig) production stimulating activity in human hybridoma HB4C5 cells and human peripheral blood lymphocytes. The biochemical and physical properties of the main active substance in kale were found to be a heat-stable protein with a molecular weight higher than 50(More)
A histone mixture (H1, H2A, H2B, H3, and H4) derived from calf thymus stimulated IgM production by human-human hybridoma HB4C5 cells. On the contrary, the histone mixture did not increase IgM production by the human Burkitt's lymphoma cell line NAT-30, IgG production by the human B lymphoblastoid cell line HMy-2, and IgE production by the human myeloma cell(More)
The effects of four ellagitannin metabolites (M1-M4) and ellagic acid on immunoglobulin E-mediated allergic responses in rat basophilic leukemia-2H3 cells were investigated. M1-M4 inhibited the antigen-induced degranulation and secretion of interleukin-4 and tumor necrosis factor-α, but ellagic acid only slightly did so under the same experimental(More)