GRP78 acts as a molecular chaperone in endoplasmic reticulum (ER) by associating transiently with incipient proteins as they traverse the ER and aiding in their folding and transport. Furthermore, the GRP78 protein is also induced under various stress condition such as glucose starvation, inhibition of protein glycosylation by tunicamycin, perturbation of ER function and protein movement by brefeldin A, and suppression of ER-calcium-ATPase pump by thapsigargin. The enhancement of ER stress response (also known as the unfolded protein response) takes part in the resistant mechanism against chemotherapy and hypoxic stress in solid tumor. The ER stress response causes an increase in gene expression of a number of ER chaperones such as GRP78 and GRP94. Thus, substances that directly down-regulate grp78 transcription are expected to be useful drugs for the treatment of solid tumor. In the course of our screening for inhibitors of luciferase expression, which is regulated under the control of GRP78 promoter, by the treatment of tunicamycin, we isolated a novel compound designated as prunustatin A from Streptomyces violaceoniger 4521-SVS3 as a down-regulator of the grp78 gene. The structure of prunustain A (C_<34>H_<40>N_2O_<12>) was elucidated on the basis of spectral analyses including 2D NMR (HMQC, DQF-COSY, HMBC). Prunustatin A consisted of a 3-formylamino-2-hydroxybezoic acid moiety as a chromophore and 15-membered macrocycles composed of an L-threonine, an L-lactatic acid, a 2R,3R-4-hydroxy-2,2-dimethyl-3-oxo-5-phenylpentanoic acid and a 2S,3S-2-hydroxy-3-methylpentanoic acid moieties. In the evaluation system we employed, prunustatin A reduced this reporter gene expression at the IC_<50> value of 1.9nM. Prunustatin A also completely inhibited the induction of endogenous GRP78 protein induced by 2-deoxyglucose at the concentration of 100nM. Prunustatin A, glucose starvation and 2-DG treatment alone did not induce cell death in cancer cells. However, prunustatin A specifically elicited global cell death when combined with 2-deoxyglucose. Thus, it is expected that prunustatin A would be a promising cancer chemotherapeutic agent against solid tumor.

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近年，食品成分が免疫系に作用することが示され，これらを利用した新規機能性食品の開発が進められている．腸管には最大級の免疫系が存在し，食品成分の作用を受けるのはこの腸管免疫系である．腸管においては，(1)経口摂取されたタンパク質抗原に対して免疫応答が抑制され，食物アレルギーの抑制機構とされる「経口免疫寛容」，(2)腸管粘膜における感染防御を担い，腸内共生菌を制御するIgA抗体分泌，そして(3)腸管バリアの防御に働くTh17細胞が誘導される，といった特徴的な免疫応答が誘導されることが知られるが，このような応答は，腸管に存在する独特の性質を有する免疫細胞によって担われることが最近の研究で明らかになってきた．本稿では，これら腸管特有の細胞群について紹介する（図1, 概念図で組織的な配置は考慮されていない）．特にIgA抗体産生，および「経口免疫寛容」それぞれに重要な腸管樹状細胞について詳細に解説する．また，IgA抗体産生を増強することを見いだしたCD3^-IL-2R⁺細胞や最近注目されている非血球系細胞として腸管免疫組織を構築するストローマ細胞についても紹介したい．また，これら腸管免疫細胞は，腸内細菌および食品成分の作用が注目される．腸内には，100兆個とも言われる腸内共生菌が生息しており，これらが免疫系の正常な発達，生体の恒常性に重要であることが明らかになってきている．これら腸内共生菌，さらに，プロバイオティクス，プレバイオティクスをはじめ，種々の食品成分は，これら腸管免疫細胞に少なからず作用すると考えられる．

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When the spore of Equisetum is soaked in water and kept at temperature of about 20°to 25℃, it begins to germinate in several hours. The spores of Equisetum arvcnse L. were soaked in 10ml of tap water filtrated through the exchange resin. The first investigation was carried out to determine the relation between the density and the germination of spore. The quantities of spore, which were soaked in 10ml of water, were 10^<-1>, 5×10^<-2>, 10^<-2>, 10^<-3>, 10^<-4>, 10^<-5>and 10^<-6>g. The spores in water sank to the bottom. Therefore, the bottom area of container influences the germination of the spores soaked in water. The optimum density of the spore was from about 4×10^<-3> to 1×10^<-4> g per 10sq. cm. The higher density of spore inhibited remarkably the germination in water, but there was no great difference in the rate of germination among a series of the lower densities. This optimum density(4×10^<-3>g per 10sq. cm)was equivalent to 10g of spore per 10ml of water in the Petri dish with about 5.5cm in diameter. All the following tests were carried out in the optimum density using the Petri dish. The spores did not germinate in 8 hours after soaking in water at about 23℃, but germinate by 24 hours. They did not germinate in water of 5℃. The study on the effect of water-exchange on the germination of spores in water was performed as follows : (1) The water in which the spores were soaked at about 23℃ was exchanged for fresh tap water after 8 hours from the beginning of the experiment. The spores were exposed to scattered light during presoaking process. (2) The water in which the spores were soaked at 5℃ was exchanged for fresh tap water after 24 hours. The spores were placed in the dark. (3)The water in which the spores were soaked at 23℃ was exchanged for fresh tap water after 24 hours. The spores were exposed to scattered light for the first about 10 hours of presoaking process. In (1) and (2), when water was exchanged, the spores did not germinate yet, but in (3) germinated already. After exchange of water, all the sets were placed in the room of about 23℃, and the spores were observed on the germination after 30 hours. The sets in which water was exchanged before the germination of spores showed a decrease in the rate of germination as compared with that of the respective controls in which the water was not exchanged. Exchanging water after germination gave no effect on the subsequent growth of rhizoid.

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The azuki bean weevil which had been reared continuously under constant laboratory conditions for many years using the azuki bean, Phaseolus angularis Wight, for food, was removed to the soy bean, Glycine Max Merrill, The growth form of the weevil population was investigated in the soy beans by counting the adult weevil every week. It was found that the growth of the third generation was greater than that of normal cases (Fig. 1). The reason was analysed experimentally. The results of experiments were analysed concerning with the change of sex ratio, developmental period, mortality, and fecundity with successive generations. The sex ratio and the developmental period did not vary regularly with the progress of generation (Figs. 2,3), but the fecundity increased remarkably (Fig. 4) and the mortality decreased slowly with the advance of generation (Fig. 5). Therefore the rate of increase as represented by the number of progenies per female increased with generations (Fig. 6). It became clear that the reason why the population growth form of the azuki bean weevil removed from azuki beans to soy beans did not show a normal form was partially the increase of reproductivity with generations. In discussion, it was considered that the selection was insufficient to interpret these results.

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