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931.
Jun-ichi Kido Noriyuki Yamauchi Keiji Ohishi Masatoshi Kataoka Seiji Nishikawa Teruo Nakamura Hiroyuki Kadono Dai Ikedo Akemichi Ueno Norio Nonomura Akihiko Okuyama Toshihiko Nagata 《Journal of cellular biochemistry》1997,67(2):248-256
Human prostatic carcinoma frequently metastasizes to bone tissue and activates bone metabolism, especially bone formation, at the site of metastasis. It has been reported that an extract of prostatic carcinoma and conditioned medium (CM) of a human prostatic carcinoma cell line, PC-3, established from a bone metastastic lesion, stimulate osteoblastic cell proliferation. However, there is little information about the effect of PC-3 CM on the differentiation of osteoblastic cells. In this study, we investigated the effect of PC-3 CM on the differentiation of two types of osteoblastic cells, primary fetal rat calvaria (RC) cells containing many undifferentiated osteoprogenitor cells, and ROS 17/2.8, a well-differentiated rat osteosarcoma cell line. PC-3 CM inhibited bone nodule formation and the activity of alkaline phosphatase (ALPase), an osteoblastic marker enzyme, on days 7, 14, and 21 (RC cells) or 3, 6, and 9 (ROS 17/2.8 cells) in a dose-dependent manner (5–30% CM). However, the CM did not affect cell proliferation or cell viability. PC-3 CM was found to markedly block the gene expression of ALPase and osteocalcin (OCN) mRNAs but had no effect on the mRNA expression of osteopontin (OPN), the latter two being noncollagenous proteins related to bone matrix mineralization. These findings suggest that PC-3 CM contains a factor that inhibits osteoblastic cell differentiation and that this factor may be involved in the process of bone metastasis from prostatic carcinoma. J. Cell. Biochem. 67:248–256, 1997. © 1997 Wiley-Liss, Inc. 相似文献
932.
Hiroko Saito Fumiko Matsukawa-Usami Toshihiko Fujimori Toshiya Kimura Takahiro Ide Takaki Yamamoto Tatsuo Shibata Kenta Onoue Satoko Okayama Shigenobu Yonemura Kazuyo Misaki Yurina Soba Yasutaka Kakui Masamitsu Sato Mika Toya Masatoshi Takeichi 《Molecular biology of the cell》2021,32(20)
Motile cilia of multiciliated epithelial cells undergo synchronized beating to produce fluid flow along the luminal surface of various organs. Each motile cilium consists of an axoneme and a basal body (BB), which are linked by a “transition zone” (TZ). The axoneme exhibits a characteristic 9+2 microtubule arrangement important for ciliary motion, but how this microtubule system is generated is not yet fully understood. Here we show that calmodulin-regulated spectrin-associated protein 3 (CAMSAP3), a protein that can stabilize the minus-end of a microtubule, concentrates at multiple sites of the cilium–BB complex, including the upper region of the TZ or the axonemal basal plate (BP) where the central pair of microtubules (CP) initiates. CAMSAP3 dysfunction resulted in loss of the CP and partial distortion of the BP, as well as the failure of multicilia to undergo synchronized beating. These findings suggest that CAMSAP3 plays pivotal roles in the formation or stabilization of the CP by localizing at the basal region of the axoneme and thereby supports the coordinated motion of multicilia in airway epithelial cells. 相似文献
933.
934.
Naoki Nishizawa Yoko Kanematsu-Yamaki Masaaki Funata Hiroaki Nagai Ayako Shimizu Hisashi Fujita Junichi Sakamoto Shiro Takekawa Taiji Asami 《Bioorganic & medicinal chemistry letters》2017,27(20):4626-4629
Neuromedin U (NMU) mediates various physiological functions via NMUR1 and NMUR2 receptors. NMUR2 has been considered a promising treatment option for diabetes and obesity. Although NMU-8, a shorter peptide, has potent agonist activity for both receptors, it is metabolically unstable. Therefore, NMU-8 analogs modified with long-chain alkyl moieties via a linker were synthesized. An octadecanoyl analog (17) with amino acid substitutions [αMePhe19, Nle21, and Arg(Me)24] and a linker [Tra-γGlu-PEG(2)] dramatically increased NMUR2 selectivity, with retention of high agonist activity. Subcutaneous administration of 17 induced anorectic activity in C57BL/6J mice. Owing to its high metabolic stability, 17 would be useful in clarifying the physiological role and therapeutic application of NMU. 相似文献
935.
Kazuki Fujita Takashi Kunito Hitoshi Moro Hideshige Toda Shigeto Otsuka Kazunari Nagaoka 《Biogeochemistry》2017,132(3):325-342
According to the resource allocation model for extracellular enzyme synthesis, microorganisms should preferentially allocate their resources to phosphorus (P)-acquiring enzyme synthesis when P availability is low in soils. However, the validity of this model across different soil types and soils differing in their microbial community composition has not been well demonstrated. Here we investigated whether the resource allocation model for phosphatase synthesis is applicable across different soil types (Andosols, Acrisols, Cambisols, and Fluvisols) and land uses (arable and forest), and we examined which soil test P and/or P fraction microorganisms responded to when investing their resources in phosphatase synthesis in the soils. The ratio of alkaline phosphatase (ALP) to β-d-glucosidase (BG) activities in the arable soils and the ratio of acid phosphatase (ACP) to BG activities in the forest soils were significantly negatively related with the available inorganic P concentration. We also observed significant effects of available inorganic P, pH, soil types, and land uses on the (ACP + ALP)/BG ratio when the data for the arable and forest soils were combined and used in a stepwise multiple regression analysis. These results suggest that microbial resource allocation for phosphatase synthesis is primarily controlled by available inorganic P concentration and soil pH, but the effects of soil types and land uses are also significant. 相似文献
936.
Suzuki Hajime Sakabe Takahiro Hirose Yuu Eki Toshihiko 《Applied microbiology and biotechnology》2017,101(2):659-671
Applied Microbiology and Biotechnology - We aimed to develop the bioassays for genotixicity and/or oxidative damage using the recombinant yeast. A genotoxicity assay was developed using recombinant... 相似文献
937.
Establishment of a new conditionally immortalized human skeletal muscle microvascular endothelial cell line
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938.
The neuroprotective effect of latanoprost acts via klotho‐mediated suppression of calpain activation after optic nerve transection
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939.
Xiaoyu Song Biao Zhou Lingyu Cui Di Lei Pingping Zhang Guodong Yao Mingyu Xia Toshihiko Hayashi Shunji Hattori Yuko Ushiki-Kaku Shin-ichi Tashiro Satoshi Onodera Takashi Ikejima 《Neurochemical research》2017,42(4):1073-1083
Alzheimer’s disease (AD) is a progressive, neurodegenerative disease. Accumulating evidence suggests that inflammatory response, oxidative stress and autophagy are involved in amyloid β (Aβ)-induced memory deficits. Silibinin (silybin), a flavonoid derived from the herb milk thistle, is well known for its hepatoprotective activities. In this study, we investigated the neuroprotective effect of silibinin on Aβ25-35-injected rats. Results demonstrated that silibinin significantly attenuated Aβ25-35-induced memory deficits in Morris water maze and novel object-recognition tests. Silibinin exerted anxiolytic effect in Aβ25-35-injected rats as determined in elevated plus maze test. Silibinin attenuated the inflammatory responses, increased glutathione (GSH) levels and decreased malondialdehyde (MDA) levels, and upregulated autophagy levels in the Aβ25-35-injected rats. In conclusion, silibinin is a potential candidate for AD treatment because of its anti-inflammatory, antioxidant and autophagy regulating activities. 相似文献
940.