Toshiaki Amamoto

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15-Lipoxygenase (15-LOX) is one of the key enzymes responsible for the formation of oxidized low-density lipoprotein (ox-LDL), a major causal factor for atherosclerosis. Both enzymatic (15-LOX) and non-enzymatic (Cu(2+)) mechanisms have been proposed for the production of ox-LDL. We have recently reported that cannabidiol-2',6'-dimethyl ether (CBDD) is a(More)
Prolonged dietary restriction has been reported to suppress age-induced phenomena. In order to investigate how prolonged caloric restriction reduces age-related deterioration of hippocampal synaptic transmission, we compared the levels of major hippocampal polyunsaturated fatty acids, arachidonic acid and docosahexaenoic acid between 4- and 26-month-old(More)
Cannabidiol (CBD), a major non-psychotropic constituent of fiber-type cannabis plant, has been reported to possess diverse biological activities, including anti-proliferative effect on cancer cells. Although CBD is obtained from non-enzymatic decarboxylation of its parent molecule, cannabidiolic acid (CBDA), few studies have investigated whether CBDA itself(More)
exo-Methylene lactone group-containing compounds, such as (--)-xanthatin, are present in a large variety of biologically active natural products, including extracts of Xanthium strumarium (Cocklebur). These substances are reported to possess diverse functional activities, exhibiting anti-inflammatory, antimalarial, and anticancer potential. In this study,(More)
Purpose. Insulin-like growth factor 1 (IGF-1) is predominantly bound to its specific binding proteins (IGFBPs) in circulating plasma. In the present study, pharmacokinetic analysis of IGF-1 was performed in healthy volunteers to characterize the effect of interactions with IGFBPs on IGF-1 disposition. Methods. Plasma concentration profiles of both free and(More)
Previously, we reported that (-)-xanthatin, a naturally occurring xanthanolide present in the Cocklebur plant, exhibits potent anti-proliferative effects on human breast cancer cells, accompanied by an induction of the growth arrest and DNA damage-inducible gene 45γ (GADD45γ), recognized recently as a novel tumor suppressor gene. However, the mechanisms(More)
15-Lipoxygenase (15-LOX) is one of the key enzymes responsible for the formation of oxidized low-density lipoprotein, a major causal factor for atherosclerosis. Δ(9)-Tetrahydrocannabinol (Δ(9)-THC), a major component of marijuana, has suggested to suppress atherosclerosis. Although Δ(9)-THC seems to be attractive for the prevention of atherosclerosis, there(More)
To investigate gene(s) being regulated by ∆(9)-tetrahydrocannabinol (∆(9)-THC), we performed DNA microarray analysis of human breast cancer MDA-MB-231 cells, which are poorly differentiated breast cancer cells, treated with ∆(9)-THC for 48 hr at an IC50 concentration of approximately 25 µM. Among the highly up-regulated genes (> 10-fold) observed, fatty(More)
Δ(9)-Tetrahydrocannabinol (Δ(9)-THC) has been reported as possessing antiestrogenic activity, although the mechanisms underlying these effects are poorly delineated. In this study, we used the estrogen receptor α (ERα)-positive human breast cancer cell line, MCF-7, as an experimental model and showed that Δ(9)-THC exposures markedly suppresses 17β-estradiol(More)
We reported that (-)-xanthatin, a xanthanolide sesquiterpene lactone present in the Cocklebur plant, exhibited potent anti-proliferative effects on human breast cancer cells, in which GADD45γ, a novel tumor suppressor gene, was induced. Mechanistically, topoisomerase IIα (Topo IIα) inhibition by (-)-xanthatin was shown to be the upstream trigger that(More)