Biomedical subjects

Shuichi Takeda

Publications and source records attributed to Shuichi Takeda.

At least 19 recordsLinked to original sources

PubMed2006

Changes in serum cytokine concentrations during the menopausal transition.

OBJECTIVE: The purpose of the present study was to clarify the changes in serum concentrations of 17 cytokines in healthy women during the menopausal transition by using a multiplexed cytokine assay and to clarify the associations of these cytokines with serum estradiol concentration. METHODS: Sixteen premenopausal, 54 perimenopausal and 52 postmenopausal women were enrolled in this study. Seventeen cytokines in serum samples were measured simultaneously using a Bio-Plex human cytokine 17-Plex assay. RESULTS: Serum IL-6 concentration showed a weak positive correlation with age (r=0.196, p<0.05). Postmenopausal women for whom less than 5 years had passed since menopause showed significant (p<0.05) increase in serum concentrations of IL-2, GM-CSF and G-CSF, while serum IL-4 concentration was significantly (p<0.05) increased in postmenopausal women for whom more than 5 years had passed since menopause. Serum estradiol concentration showed a significant negative correlation with serum IL-6 concentration and weak negative correlations with serum concentrations of IL-2, IL-8 and GM-CSF. CONCLUSION: We were able to simultaneously measure the levels of 17 cytokines using a highly sensitive cytokine assay, and we found that the changes in serum cytokine concentrations during the menopausal transition differed. We also found that serum IL-6 concentration during the menopausal transition was negatively correlated with serum estradiol concentration.

Adult↗

PubMed2006

Structural basis of actin filament capping at the barbed-end: a cryo-electron microscopy study.

The intracellular distribution and migration of many protein complexes and organelles is regulated by the dynamics of the actin filament. Many actin filament end-binding proteins play crucial roles in actin dynamics, since polymerization and depolymerization of actin protomers occur only at the filament ends. We present here an EM structure of the complex of the actin filament and hetero-dimeric capping protein (CP) bound to the barbed-end at 23 A resolution, by applying a newly developed methods of image analysis to cryo-electron micrographs. This structure was fitted by the crystal structure of CP and the proposed actin filament structure, allowing us to construct a model that depicts two major binding regions between CP and the barbed-end. This binding scheme accounted for the results of newly performed and previously published mutation experiments, and led us to propose a two-step binding model. This is the first determination of an actin filament end structure.

Actin Cytoskeleton↗

PubMed2006

Association of interleukin-8 with hot flashes in premenopausal, perimenopausal, and postmenopausal women and bilateral oophorectomized women.

OBJECTIVE: The purpose of this study was to identify serum cytokine concentrations in premenopausal, perimenopausal, and postmenopausal women and bilateral oophorectomized women with hot flashes. METHODS: Serum concentrations of 17 cytokines were simultaneously measured using a multiplexed human cytokine assay in 129 premenopausal, perimenopausal, and postmenopausal women and 50 bilateral oophorectomized women. RESULTS: Serum IL-8 concentrations in midlife women and bilateral oophorectomized women with severe hot flashes were significantly higher than the concentrations in women without hot flashes and women with mild and moderate hot flashes. Serum macrophage inflammatory protein-1beta concentration in women with severe hot flashes was significantly higher than those in women without hot flashes and women with mild and moderate hot flashes. CONCLUSION: Serum IL-8 concentrations in premenopausal, perimenopausal, and postmenopausal women and bilateral oophorectomized women with hot flashes were significantly higher than those in women without hot flashes. IL-8 may be associated with peripheral vasodilation in women with hot flashes.

Adult↗

PubMed2006

Antinociceptive effect of methyleugenol on formalin-induced hyperalgesia in mice.

The effects of methyleugenol, an essential oil isolated from Asiasari radix, on antinociception were examined using the formalin test in mice. Oral administration of 10 mg/kg methyleugenol significantly decreased the duration of licking and biting behavior in the second phase without affecting that of the first phase, as did diclofenac, a non-steroidal anti-inflammatory drug. Methyleugenol also inhibited pain-related behaviors induced by intrathecal injection of N-methyl-d-aspartic acid (NMDA), while diclofenac did not affect these behaviors. These effects of methyleugenol were suppressed by bicuculline, a gamma-aminobutyric acid(A) (GABA(A)) antagonist. Muscimol, a GABA(A) agonist, displays the same action as methyleugenol with respect to the formalin test and NMDA-induced behaviors. Methyleugenol did not affect cyclooxygenase-1 and -2 activities. These results suggest that the antinociceptive effect of methyleugenol on the second phase of formalin-induced pain may be due to the inhibition of NMDA receptor-mediated hyperalgesia via GABA(A) receptors.

Anesthetics↗

PubMed2006

Opening of holes in liposomal membranes is induced by proteins possessing the FERM domain.

The destabilization of vesicles caused by interactions between lipid bilayers and proteins was studied by direct, real-time observation using high-intensity dark-field microscopy. We previously reported that talin, a cytoskeletal submembranous protein, can reversibly open stable large holes in giant liposomes made of neutral and acidic phospholipids. Talin and other proteins belonging to the band 4.1 superfamily have the FERM domain at their N-terminal and interact with lipid membranes via that domain. Here, we observed that band 4.1, ezrin and moesin, members of the band 4.1 superfamily, are also able to open stable holes in liposomes. However, truncation of their C-terminal domains, which can interact with the N-terminal FERM domain, impaired their hole opening activities. Oligomeric states of ezrin affected the capability of the membrane hole formation. Phosphatidylinositol bisphosphate (PIP2), which binds to the FERM domain and disrupts the interaction between the N and C termini of the band 4.1 superfamily, down-regulates their membrane opening activity. These results suggest that the intermolecular interaction plays a key role in the observed membrane hole formation.

Animals↗

PubMed2006

Intestinal anastomosis surgery with no septic shock primes for a dysregulatory response to a second stimulus.

BACKGROUND: Major surgery is believed to contribute to immune dysregulation and high susceptibility to microbes. Recently, the inflammatory "two-hit" model has been accepted to elucidate development of multiple organ failure in surgical patients. Our purpose was to examine whether intestinal surgery, which causes a minor insult with no septic shock, may modify the immune response to exogenous LPS as a second stimulus. MATERIALS AND METHODS: Using a rat intestinal transection and anastomosis surgery model, we sequentially examined blood cell counts, body temperatures, and plasma cytokines. Rats were administered with LPS intravenously or intratracheally various days after surgery. Phagocytic activity and TNFalpha production in bronchoalveolar lavage (BAL) cells, plasma cytokines, and survival rates were evaluated. RESULTS: The surgery itself caused no severe shock or circulating cytokine elevation, whereas the number of granulocytes in the blood was significantly elevated after surgery. LPS-induced elevation of circulating IFNgamma attenuated 3 days after surgery. In contrast, IL-10 was enhanced 3-10 days after surgery. Hyporesponsiveness of BAL cells to LPS was observed 3 days after surgery but not the next day after surgery. However, rats intratracheally exposed to LPS 10-13 days after surgery exhibited higher mortality. CONCLUSIONS: Although our surgical procedure was not supposed to be a severe insult, it sufficiently primed rats for an altered response to a second stimulus (endotoxin), which included enhanced mortality. This study provided an improved understanding of pathophysiological changes following surgery and described a useful model for developing preventive and therapeutic strategies for complications after surgery.

Anastomosis, Surgical↗

PubMed2006

Effects of Saireito, a Japanese herbal medicine, on edema via antagonistic actions against aldosterone in anti-GBM nephritic rats.

BACKGROUND: In order to clarify the diuretic mechanisms of Saireito, a Japanese herbal medicine, the mineralcorticoid receptor antagonistic action of Saireito was evaluated in anti-glomerular basement membrane (GBM) nephritic rats. METHODS: Anti-GBM nephritis was induced in rats by the intravenous, injection of anti-GBM serum, and test drugs were administered 5 days after the induction of nephritis. In addition, we also investigated aldosterone-loaded mice to clarify the effects of test drugs on aldosterone signal transduction. In an in vitro study, a mineralocorticoid receptor binding assay of the components of Saireito was performed. RESULTS: Saireito and spironolactone inhibited the development of proteinuria and abdominal ascites in anti-GBM nephritic rats. Saireito and spironolactone increased the urine volume and decreased the abdominal saline content in aldosterone-loaded mice. Saikosaponin H, a component of Saireito, inhibited the receptor binding of aldosterone in the in vitro assay 50% inhibitory concentration ([IC(50)], 22 micromol/l). Saikosaponin H also inihibited the decrease in urine volume in aldosterone-loaded mice. CONCLUSIONS: These results suggest that the diuretic action of Saireito may be partly due to an antagonistic action on the mineralocorticoid receptor, exerted by saikosaponin H.

Aldosterone↗

PubMed2006

Insulin resistance and low sympathetic nerve activity in the Tsumura Suzuki obese diabetic mouse: a new model of spontaneous type 2 diabetes mellitus and obesity.

Tsumura Suzuki obese diabetic (TSOD) mouse is a new model of type 2 diabetes mellitus and obesity. The TSOD mice had hypoadiponectinemia. To assess the glucose utilization and insulin sensitivity, we examined the effect of insulin (1U/kg) on peripheral tissue glucose uptake in vivo in the TSOD and Tsumura Suzuki nonobese mouse using 2-deoxy-d-[(3)H]glucose. The rates constant of glucose uptake in basal condition without insulin were similar in the peripheral tissues in both strains. Insulin-stimulated glucose uptake by skeletal muscles and adipose tissues in vivo was diminished in the TSOD mice. In addition, we assessed norepinephrine turnover in brown adipose tissue and adrenal epinephrine (E) content and E turnover because disturbances in the sympathetic activities relate to many features in obese and diabetic syndrome. In these mice, the rate of norepinephrine turnover was decreased, and adrenal E content was at most one half of the Tsumura Suzuki nonobese mice and E turnover had extremely low rates. The TSOD mice showed hypercorticosteronemia. These results suggest that TSOD mice have insulin resistance and both low sympathetic nervous activities and low adrenomedullary activity, and have high adrenocortical activity, which are significant features of the TSOD mouse.

Adiponectin↗

PubMed2006

Indoor cultivation and cultural characteristics of Wolfiporia cocos sclerotia using mushroom culture bottles.

We newly developed an indoor cultivation technique for Wolfiporia cocos (Wolf) Ryvarden et Gilbertson (Syn. Poria cocos Wolf), not with soil, but using mushroom culture bottles with pine logs, and clarified some cultural characteristics of sclerotia in the laboratory. To determine the optimum conditions for sclerotia growth, the weight of sclerotia and concentration of CO2 in three different air filters; cloth, paper and urethane resin, and closed bottles were tested. When the cloth air filter was used, the growth rate was the fastest and the yield was maximal. These results suggested that the aeration was an important environmental factor for cultivation. To clarify the characteristics of culture in the cloth air filtered and closed bottles, the weight of sclerotia, the compositions of pine logs and the contents of pachymic acid and dehydropachymic acid were examined during 24 weeks. The growth of scleroia and the wood decaying efficiency in the cloth air filtered bottles were better than those in the closed bottles. Also, it was found that W. cocos was a brown rot fungus due to the alkaline solubility of pine logs in the wood decay process. In addition, the contents of pachymic acid and dehydropachymic acid and the TLC pattern between the cultivated and commercial sclerotia did not differ remarkably.

Aerobiosis↗

PubMed2006

Identification of medicinal Atractylodes based on ITS sequences of nrDNA.

Dried rhizomes of five species of Atractylodes (A. japonica, A. macrocephala, A. lancea, A. chinensis, and A. koreana), Compositae, have been used as crude drugs mainly for the treatment of stomach disorders and for their diuretic properties in Chinese and Japanese traditional medicines. The identification of the botanical origins of these crude drugs is generally difficult from their morphological and chemical features only. In this study, for identification with more reliable, nuclear ribosomal DNA (nrDNA), internal transcribed spacer (ITS) regions of five species of medicinal Atractylodes were sequenced. As a result, specific ITS genotypes were recognized by each species. The four species (A. japonica, A. macrocephala, A. lancea, and A. chinensis) prescribed in Chinese and Japanese Pharmacopoeias as botanical origins of crude Atractylodes drugs could be distinguished by their ITS sequences because they had difference genotypes on the ITS sequences. However, the genotype of A. koreana was the same as that of A. chinensis. Additionally, hybrids between A. lancea and A. chinensis were also recognized as nucleotide additives on their ITS sequences. In this study, several morphological characteristics were researched by their genotype, too. As this result, the hybrids recognized from the genetic analysis had intermediate morphological characteristics between A. lancea and A. chinensis. It was also recognized that A. lancea and A. chinensis except for their hybrids were significant differences. It is therefore suggested that ITS sequences of nrDNA would be useful for the identification of the crude drugs derived from Atractylodes species and their interspecific hybridizations.

Atractylodes↗

PubMed2006

Type 2 diabetes mellitus in obese mouse model induced by monosodium glutamate.

The number of diabetic patients is increasing every year, and new model animals are required to study the diverse aspects of this disease. An experimental obese animal model has reportedly been obtained by injecting monosodium glutamate (MSG) to a mouse. We found that ICR-MSG mice on which the same method was used developed glycosuria. Both female and male mice were observed to be obese but had no polyphagia, and were glycosuric by 29 weeks of age, with males having an especially high rate of incidence (70.0%). Their blood concentrations of glucose, insulin, total cholesterol, and triglycerides were higher than in the control mice at 29 weeks. These high concentrations appeared in younger males more often than in females, and were severe in adult males. Also, the mice at 54 weeks of age showed obvious obesity and increased concentrations of glucose, insulin, and total cholesterol in the blood. The pathological study of ICR-MSG female and male mice at 29 weeks of age showed hypertrophy of the pancreatic islet. This was also observed in most of these mice at 54 weeks. It was recognized as a continuation of the condition of diabetes mellitus. From the above results, these mice are considered to be useful as new experimental model animals developing a high rate of obese type 2 (non-insulin dependent) diabetes mellitus without polyphagia.

Animals↗

PubMed2005

Antinociceptive effect of shakuyakukanzoto, a Kampo medicine, in diabetic mice.

In this study, the antinociceptive effect of shakuyakukanzoto was investigated using streptozotocin-induced diabetic mice to certify its analgesic effect on diabetic patients. Shakuyakukanzoto (0.5 and 1.0 g/kg, p.o.) significantly increased the nociceptive threshold in diabetic mice. The antinociceptive activity of shakuyakukanzoto in diabetic mice was not antagonized by beta-funaltrexamine, naltrindole, or nor-binaltorphimine. The increased antinociceptive activity of (1.0 g/kg, p.o.) in diabetic mice was abolished by yohimbine (15 microg, i.t.), but not by NAN-190 (1 microg, i.t.), methysergide (15 microg, i.t.), or MDL-72222 (15 microg, i.t.). In shakuyakukanzoto diabetic mice treated with 6-hydroxydopamine (20 microg, i.t.) chemically lesioned noradrenergic pathways, shakuyakukanzoto (1.0 g/kg, p.o.) failed to exhibit an antinociceptive effect. Furthermore, the antinociceptive activity induced by norepinephrine (0.06 - 2 microg, i.t.) was markedly more potent in diabetic mice than in non-diabetic mice at the same dose. These results suggest that the antinociceptive effect of shakuyakukanzoto in diabetic mice is not mediated by the opioid systems and that this effect appears via selective activation of the spinal descending inhibitory alpha2-adrenergic systems without activating the serotonergic systems. The spinal alpha2-adrenoceptor-mediated analgesic mechanism was enhanced in diabetic mice, suggesting that shakuyakukanzoto exhibits its effect by activating the descending noradrenergic neurons.

Adrenergic alpha-Antagonists↗

PubMed2005

Effects of Byakko-ka-ninjin-to on salivary secretion and bladder function in rats.

Byakko-ka-ninjin-to (BN) is a Kampo medicine (traditional Japanese medicine) that is frequently used to treat xerostomia, which is also a side effect of anticholinergic agents such as oxybutynin and propiverine widely used for the treatment of patients with urinary incontinence or frequency. We investigated the effects of BN on salivation and bladder function in rats, in the presence and absence of oxybutynin. Treatment with BN alone resulted in a slight increase in salivary secretions. In contrast, pilocarpine, a known muscarinic agonist, produced a significant increase in salivary secretions that could be blocked by pretreatment with oxybutynin. A single oral dose of BN at 200mg/kg body weight just before oxybutynin treatment resulted in less inhibition by oxybutynin of pilocarpine-induced salivation. However, BN had no effect on the decreased amplitude of bladder contractions that result from oxybutynin administration. These results suggest that BN might be useful for the xerostomia induced by anticholinergic agents, without influencing their beneficial effect on micturition.

Animals↗

PubMed2005

The effect of herbal medicine Toki-shakuyaku-san on blood pressure in an Nomega-nitro-L-arginine methyl ester-induced pre-eclampsia rat model during pregnancy and the postpartum period.

The chronic inhibition of nitric oxide (NO) synthesis with N(omega)-nitro-L-arginine methyl ester (L-NAME) in pregnant rats induces a pre-eclampsia-like syndrome, including hypertension. We have previously reported the beneficial effects of Toki-shakuyaku-san (TS) in this model. In the present study we demonstrated the anti-hypertensive effect of TS in pre-eclampsia produced by prolonged L-NAME-infusion during the postpartum period. Analysis of blood sex steroids suggested that the level of progesterone differs between the TS-effective (gestational day 19 and postpartum day 7) and TS-ineffective (postpartum day 1) periods. Co-administration of TS and progesterone inhibited L-NAME-induced hypertension on postpartum day 1. Furthermore, the anti-hypertensive effect of TS on postpartum day 6 disappeared in the presence of a co-administered progesterone antagonist mifepristone. These data suggest that a certain level of progesterone may be an indispensable prerequisite for an anti-hypertensive effect of TS. Finally, the effects of TS are apparently unrelated to blood levels of NO, calcitonin gene-related peptide, and endothelin-1, which have been reported to modulate systolic blood pressure in the L-NAME-induced pre-eclampsia model. Thus, the use of TS may provide a new therapeutic strategy for pre-eclampsia, although elucidation of the mechanism of action of TS would be necessary to optimize treatment protocols.

Animals↗

PubMed2005

Effects of rikkunshi-to, a traditional Japanese medicine, on the delay of gastric emptying induced by N(G)-nitro-L-arginine.

We evaluated the effects of Rikkunshi-to and several of its ingredients on the delay of gastric emptying induced by a nitric oxide (NO) synthase inhibitor, N(G)-nitro-L-arginine (L-NNA). After oral administration of L-NNA to rats, the gastric emptying rate at 24 h was decreased from 82.8 +/- 2.4% to 53.3 +/- 5.7%. The decrease of the gastric emptying rate induced by L-NNA treatment was markedly ameliorated by administration of Rikkunshi-to (250 and 500 mg/kg, p.o.) in a dose-dependent manner. To identify the active ingredient of Rikkunshi-to, the components were separated according to polarity, and the effects of the respective fractions on gastric emptying were evaluated. Significant efficacy was found in the water and methanol fractions, but not in the 50% aqueous-methanol fraction. Furthermore, hesperidin (1 - 4.29 mg/kg, p.o.) contained in the methanol fraction and L-arginine (4.5 mg/kg, p.o.) contained in the water fraction ameliorated the decrease in the gastric emptying rate induced by L-NNA treatment. These results suggest that Rikkunshi-to ameliorated abnormalities of NO-mediated gastric functions such as delayed gastric emptying, and hesperidin and L-arginine were identified as two of the active ingredients contributing to the ability of Rikkunshi-to to facilitate gastric emptying.

Administration, Oral↗

PubMed2005

Skin temperature rise induced by calcitonin gene-related peptide in gonadotropin-releasing hormone analogue-treated female rats and alleviation by Keishi-bukuryo-gan, a Japanese herbal medicine.

The effects of Keishi-bukuryo-gan on calcitonin gene-related peptide (CGRP)-induced elevation of skin temperature were investigated in gonadotropin-releasing hormone (GnRH) analogue-treated female rats. Leupline (1.0 mg/kg) as the GnRH analogue was subcutaneously (s.c.) injected into female rats. After Keishi-bukuryo-gan (100-1,000 mg/kg, p.o.) or 17beta-estradiol (0.010 mg/kg, s.c.) was administered to GnRH analogue-treated rats for 14 days, CGRP-induced skin temperature elevation, concentration of plasma 17beta-estradiol and pituitary gonadotropin (luteinizing hormone; LH, and follicle stimulating hormone; FSH) were measured. In addition, effects of 17beta-estradiol and Keishi-bukuryo-gan on the proliferation of estrogen-dependent human breast cancer (MCF-7) cells were investigated under in vitro conditions. GnRH analogue significantly lowered the concentrations of plasma 17beta-estradiol and pituitary gonadotropins. Tissue weights of the ovaries and uterus were also decreased by the analogue. Under the condition of estrogen deficiency, intravenous (i.v.) injection of exogenous CGRP (10 microg/kg) elevated the skin temperature of the hind paws more significantly than it did in sham-treated control rats. Estrogen supplementation inhibited this elevation of skin temperature with restoration of both the lowered plasma estrogen level and the decreased uterine weight in GnRH analogue-treated rats. On the other hand, Keishi-bukuryo-gan inhibited the elevation of skin temperature in a dose-dependent manner without restoring the plasma estrogen level and uterine weight. In addition, in an in vitro study, MCF-7 cells proliferated in a dose-dependent manner by the addition of 17beta-estradiol (10(-13)-10(-8) M) to the medium. However, Keishi-bukuryo-gan (10(-6)-10(-4) mg/ml) did not activate the MCF-7 cell proliferation. These results suggest that Keishi-bukuryo-gan, which does not exhibit estrogen activity, may be useful for the treatment of hot flashes in women who are undergoing medical ovariectomy with a GnRH analogue.

Animals↗

PubMed2005

The herbal medicine Sho-saiko-to selectively inhibits CD8+ T-cell proliferation.

Sho-saiko-to (SST), a Chinese/Japanese traditional herbal medicine, has been widely used to treat chronic hepatitis in Japan, and the immunomodulatory properties of SST are likely to mediate its beneficial effect. In the present study, we examined the effects of SST and its various ingredients on the count and proliferation of T-cell subsets in cultured splenocytes and hepatic mononuclear cells. SST, wogonin-7-O-glucuronoside (a major SST ingredient), and wogonin (an intestinal metabolite of wogonin-7-O-glucuronoside) increased CD4/CD8 ratio via a decrease of CD8+ T-cell counts with no effect on CD4+ T-cell counts. Flow cytometric analyses of viability, proliferation, and cell cycle revealed that wogonin suppressed CD8+ T-cell proliferation without inducing cell death. SST and wogonin administered to mice increased the CD4/CD8 ratio in hepatic mononuclear cells but not in splenocytes. These findings suggest that SST may modulate the CD4/CD8 ratio via the selective inhibition of CD8+ T-cell proliferation by the SST ingredient wogonin-7-O-glucuronoside or its metabolite wogonin.

Animals↗

PubMed2005

The influence of the sennosides on absorption of glycyrrhetic acid in rats.

In the course of our clinical studies of Kampo medicine (traditional Japanese medicines), we observed the pharmacokinetic interactions between two herbs. When Onpito (TJ-8117, Kampo medicine) containing licorice and rhubarb was administered orally to human subjects, we observed that the AUC(0-lim) and Cmax of glycyrrhetic acid (GA) in plasma were lower than those treated with other Kampo medicines containing licorice. In this study, we demonstrate the pharmacokinetic interactions of GA derived from glycyrrhizinic acid (GL) in licorice and anthraquinones derived from rhubarb. To our knowledge, this is the first report to investigate the pharmacokinetic interactions between two herbs. When GL was orally co-administrated to rats with a non-effective dose of sennoside A having purgative activity, the AUC(0-lim) and Cmax of GA decreased. In addition, sennoside A did not affect the metabolism of GL by the intestinal bacteria in vitro. In the examination using an in situ loop of rat colon, the remaining ratio of GA rose drastically by the co-administration of sennoside A, sennidin A and rhein. Observed inhibition activity of these anthraquinones on GA absorption depended on the concentration of the components added. The maximum inhibition ratio was approximately 75% by rhein, 60% by sennoside A and 25% by sennidin A. We conclude that the decrease of the pharmacokinetic parameters of GA in human plasma observed in the clinical study of TJ-8117 is attributable to an interactive action of absorption from the intestinal tract by anthraquinones contained in or derived from rhubarb.

Animals↗