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61.
Shibayama Y Kawachi A Onimaru S Tokunaga J Ikeda R Nishida K Kuchiiwa S Nakagawa S Takamura N Motoya T Takeda Y Yamada K 《Life sciences》2007,81(2):103-108
An herbal health care supplement, St John's Wort (SJW, Hypericum perforatum) has become widely used in the treatment of depression, and is known to interact with therapeutic drugs. Here we report a preventive effect of SJW on cisplatin nephrotoxicity in rats. Rats were given SJW (400 mg/kg/day, p.o.) for 10 consecutive days, and were injected with cisplatin (5 mg/kg, i.v.) on the day after the final SJW treatment. Cisplatin treatment increased the serum creatinine level, which is an index of nephrotoxicity, to 1.51+/-0.22 mg/dl (mean+/-SE) from 0.28+/-0.05 mg/dl (control) on day 5 after the cisplatin injection. This increase fell significantly to 0.86+/-0.13 mg/dl by pre-treatment with SJW. Cisplatin-induced histological abnormality of the kidney was blocked by pre-treatment with SJW. When SJW was administered for 10 days, the amounts of renal metallothionein (MT) and hepatic multidrug resistance protein 2 (Mrp2) were increased to 164.8+/-13.0% and 220.8+/-39.3% (mean+/-SE) of controls, respectively. GSH levels in the kidney and liver were not changed. Total and free cisplatin concentration in serum was not influenced by SJW treatment. In conclusion, the results suggest that pre-treatment with SJW may diminish cisplatin nephrotoxicity. 相似文献
62.
Tsubaki M Kato C Manno M Ogaki M Satou T Itoh T Kusunoki T Tanimori Y Fujiwara K Matsuoka H Nishida S 《Molecular and cellular biochemistry》2007,304(1-2):53-60
Osteolytic lesions are rapidly progressive during the terminal stages of myeloma, and the bone pain or bone fracture that
occurs at these lesions decreases the patients’ quality of life to a notable degree. In relation to the etiology of this bone
destruction, it has been reported recently that MIP-1α, produced in large amounts in myeloma patients, acts indirectly on
osteoclastic precursor cells, and activates osteoclasts by way of bone-marrow stromal cells or osteoblasts, although the details
of this process remain obscure. In the present study, our group investigated the mechanism by which RANKL expression is induced
by MIP-1α and the effects of MIP-1α on the activation of osteoclasts. RANKL mRNA and RANKL protein expressions increased in
both ST2 cells and MC3T3–E1 cells in a MIP-1α concentration-dependent manner. RANKL mRNA expression began to increase at 1 h
after the addition of MIP-1α; the increase became remarkable at 2 h, and continuous expression was observed subsequently.
Both ST2 and MC3T3-E1 cells showed similar levels of increased RANKL protein expression at 1, 2, and 3 days after the addition
of MIP-1α. After the addition of MIP-1α, the amount of phosphorylated ERK1/2 and Akt protein expressions showed an increase,
as compared to the corresponding amount in the control group. On the other hand, the amount of phosphorylated p38MAPK protein
expression showed a decrease from the amount in the control group after the addition of MIP-1α. U0126 (a MEK1/2 inhibitor)
or LY294002 (a PI3K inhibitor) was added to ST2 and MC3T3-E1 cells, and was found to inhibit RANKL mRNA and RANKL protein
expression in these cells. When SB203580, a p38MAPK inhibitor, was added, RANKL mRNA and RANKL protein expression were increased
in these cells. MIP-1α was found to promote osteoclastic differentiation of C7 cells, an osteoclastic precursor cell line,
in a MIP-1α concentration-dependent manner. MIP-1α promoted differentiation into osteoclasts more extensively in C7 cells
incubated together with ST2 and MC3T3-E1 cells than in C7 cells incubated alone. These results suggested that MIP-1α directly
acts on the osteoclastic precursor cells and induces osteoclastic differentiation. This substance also indirectly induces
osteoclastic differentiation through the promotion of RANKL expression in bone-marrow stromal cells and osteoblasts. The findings
of this investigation suggested that activation of the MEK/ERK and the PI3K/Akt pathways and inhibition of p38MAPK pathway
were involved in RANKL expression induced by MIP-1α in bone-marrow stromal cells and osteoblasts. This finding may be useful
in the development of an osteoclastic inhibitor that targets intracellular signaling factors. 相似文献
63.
Kano Y Soda K Nakamura T Saitoh M Kawakami M Konishi F 《Cancer immunology, immunotherapy : CII》2007,56(6):771-781
Increased blood polyamine levels, often observed in cancer patients, have negative impacts on patient prognosis and are associated
with tumor progression. The purpose of our study was to examine the effects of polyamines on cellular immune function. Peripheral
blood mononuclear cells (PBMCs) from healthy volunteers were cultured with the human natural polyamines spermine, spermidine,
or putrescine, and the effects on immune cell function were examined. The correlation between post-operative changes in blood
polyamine levels and lymphokine-activated killer (LAK) activity was also examined in cancer patients. Spermine decreased the
adhesion of non-stimulated PBMCs to tissue culture plastic in a dose- and a time-dependent manner without affecting cell viability
or activity. This decrease in adhesion capacity was accompanied by a decrease in the number of CD11a bright-positive and CD56
bright-positive cells. Upon stimulation with interleukin 2 to activate LAK cytotoxicity, PBMCs cultured overnight with 100
or 500 μM spermine showed decreased cytotoxic activity against Daudi cells (91.5 ± 1.7 and 84.9 ± 3.0%, respectively (n = 6) compared to PBMC cultured without polyamines). In a group of 25 cancer patients, changes in blood spermine levels after
surgery were negatively correlated with changes in LAK cytotoxicity after surgery (r = −0.510, P = 0.008: n = 25). Increased blood spermine levels may be an important factor in the suppression of anti-tumor immune cell function. 相似文献
64.
Endogenous cannabinoids (endocannabinoids) serve as retrograde messengers at synapses in various regions of the brain. They are released from postsynaptic neurons and cause transient and long-lasting reduction of neurotransmitter release through activation of presynaptic cannabinoid receptors. Endocannabinoid release is induced either by increased postsynaptic Ca(2+) levels or by activation of G(q/11)-coupled receptors. When these two stimuli coincide, endocannabinoid release is markedly enhanced, which is attributed to the Ca(2+) dependency of phospholipase Cbeta (PLCbeta). This Ca(2+)-assisted receptor-driven endocannabinoid release is suggested to participate in various forms of synaptic plasticity, including short-term associative plasticity in the cerebellum and spike-timing-dependent long-term depression in the somatosensory cortex. In these forms of plasticity, PLCbeta seems to function as a coincident detector of presynaptic and postsynaptic activities. 相似文献
65.
Sumino H Takahashi M Yamaguchi T Abe K Araki N Yamazaki S Shimozaki S Nagano A Nishio N 《Bioresource technology》2007,98(1):177-182
A feasibility test of a 17 m3-pilot-scale sewage treatment system was carried out by continuous feeding of raw municipal sewage under ambient temperature conditions. The system consisted of a UASB and an aerated fixed bed reactor. Some of the effluent from the fixed bed reactor was returned to the UASB influent in order to provide a sulfate source. The total BOD of 148-162 mg l(-1) in the influent was reduced to a more desirable 11-25 mg l(-1) in the final effluent. The levels of methane-producing activity from acetate and H2/CO2 gas at 10 degrees C were only 2% and 0% of those at 35 degrees C, respectively. On the other hand, the sulfate-reducing activity levels of the UASB sludge were relatively high at 10 degrees C, for example, 18% for acetate and 9% for H2/CO2 gas, compared to the activity levels at 35 degrees C. Therefore, BOD oxidization by sulfate reduction in the UASB was greater than that by methane production under low temperature conditions. This sulfate-reducing activity tended to be proportional to the copy number of adenosine-5'-phosphosulfate (APS) reductase genes in DNA extracted from the sludge. 相似文献
66.
Komatsu T Hirano T Songkram C Kawachi E Kagechika H 《Bioorganic & medicinal chemistry》2007,15(9):3115-3126
Thyroid hormones play important roles in growth, development and homeostasis, and disruption of their functions induces serious disease, so novel synthetic thyroid hormone analogues are candidates for clinical application. We designed and synthesized novel diphenylamine derivatives with a thiazolidinedione moiety as the terminal polar group as thyroid hormone receptor (TR) antagonists. Compounds bearing an appropriately sized N-alkyl group showed antagonistic activities towards both the hTRalpha1 and hTRbeta1 subtypes. 相似文献
67.
Effects of dietary soybean peptides on hepatic production of ketone bodies and secretion of triglyceride by perfused rat liver 总被引:2,自引:0,他引:2
Tamaru S Kurayama T Sakono M Fukuda N Nakamori T Furuta H Tanaka K Sugano M 《Bioscience, biotechnology, and biochemistry》2007,71(10):2451-2457
Soybean protein isolate (SPI) was digested with protease to produce a peptides containing the low-molecular fraction (LD3) or a mixture of high- and low-molecular fractions (HD1). Rats were fed a diets containing SPI, LD3, or HD1 at a protein level equivalent to the 20% casein diet for 4 weeks. The serum triglyceride concentration was lower in rats fed SPI, LD3, and HD1 diets than in rats fed the casein diet, and the differences were significant for the cholesterol-enriched diet. The value for the LD3 group was the lowest among all groups for both the cholesterol-free and -enriched diets. The level of triglyceride in the post-perfused liver was significantly lower in the LD3 and HD1 groups and the SPI group than in the casein group irrespective of the presence of cholesterol in the diet. In the cholesterol-free diet, LD3 feeding as compared to casein feeding caused a reduction in triglyceride secretion from the liver to perfusate and an increment of hepatic ketone body production. The addition of cholesterol to the diets somewhat attenuated these effects of LD3. These results suggest that the low-molecular fraction in soybean peptides causes triglyceride-lowering activity through a reduction in triglyceride secretion from the liver to the blood circulation and the stimulation of fatty acid oxidation in the liver. There is a possibility that soybean peptides modulate triglyceride metabolism by changes in the hepatic contribution. 相似文献
68.
Yamamoto M Kamata T DO ND Adachi Y Kinjo M Ando T 《Bioscience, biotechnology, and biochemistry》2007,71(11):2860-2863
Female moths of Lyclene dharma dharma (Arctiidae, Lithosiinae) produced three pheromone components (I-III), which strongly stimulated male antennae. Using GC-MS analysis and chemical derivatizations, the following structures were estimated: 6-methyl-2-octadecanone (I), 14-methyl-2-octadecanone (II), and 6,14-dimethyl-2-octadecanone (III). While the stereochemistry of the chiral centers could not be determined because it was difficult to collect a sufficient amount of the natural pheromone, the plain structures of I and II were confirmed by synthesis of the racemic mixtures starting from diols. These methyl-branched ketones have not been identified as a natural product, indicating that they constitute a new chemical group of lepidopteran female sex pheromones. 相似文献
69.
Miyazawa Atsuhiro Kanahara Nobuhisa Kogure Masanobu Otsuka Ikuo Okazaki Satoshi Watanabe Yoshinori Yamasaki Fumiaki Nakata Yusuke Oda Yasunori Hishimoto Akitoyo Iyo Masaomi 《Molecular biology reports》2022,49(3):2015-2024
Molecular Biology Reports - GABAergic system dysfunction has been implicated in the etiology of schizophrenia and of cognitive impairments in particular. Patients with treatment-resistant... 相似文献
70.
We investigated ultrastructural changes in the yeast Saccharomyces cerevisiae when exposed to compressed ethylene gas. Transmission electron microscopy (TEM) revealed that intracellular organelles in yeast cells treated with compressed ethylene at up to 0.640 MPa (6.4 atm), especially the nuclear and plasma membranes, were seriously damaged. 相似文献