Biomedical subjects

Katsuko Komatsu

Publications and source records attributed to Katsuko Komatsu.

At least 19 recordsLinked to original sources

PubMed2006

Comparison of Anti-inflammatory Activities of Six Curcuma Rhizomes: A Possible Curcuminoid-independent Pathway Mediated by Curcuma phaeocaulis Extract.

We aimed to compare the anti-inflammatory activities of six species of Curcuma drugs using adjuvant arthritis model mice. When orally administered 1 day before the injection of adjuvant, the methanol extract of Curcuma phaeocaulis significantly inhibited paw swelling and the serum haptoglobin concentration in adjuvant arthritis mice. Also when orally administered 1 day after the injection of adjuvant, the methanol extract of Curcuma phaeocaulis significantly inhibited paw swelling. Other Curcuma species (Curcuma longa, Curcuma wenyujin, Curcuma kwangsiensis, Curcuma zedoaria and Curcuma aromatica) had no significant inhibitory effects on adjuvant-induced paw swelling. Cyclooxygenase (COX)-2 activity was significantly inhibited by the methanol extract of C. phaeocaulis. Curcuminoids' (curcumin, bis-demethoxycurcumin and demethoxycurcumin) were rich in C. longa, but less in C. phaeocaulis and C. aromatica, not in C. wenyujin, C. kwangsiensis and C. zedoaria, suggesting that curcuminoids' contents do not relate to inhibition of arthritis swelling. Therefore, C. phaeocaulis may be a useful drug among Curcuma species for acute inflammation, and the active constituents of C. phaeocaulis are not curcuminoids.

Journal Article↗

PubMed2006

Metabolite 1 of protopanaxadiol-type saponins, an axonal regenerative factor, stimulates teneurin-2 linked by PI3-kinase cascade.

We previously showed that 20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol (M1), a metabolite of protopanaxadiol-type ginseng saponins by intestinal bacteria had axonal extension activity in degenerated neurons, and improved memory disorder and synaptic loss induced by an active fragment of amyloid beta, Abeta(25-35). It is unknown how M1 shows these effects in neurons. To clarify the signal transduction mechanism of M1-induced axonal extension, phosphorylated proteins by M1 stimulation were identified because most cellular signal pathways are regulated by phosphorylation/dephosphorylation. The combination of immunoprecipitation and MALDI-TOF-MS revealed that teneurin-2 and mPar3 were specifically phosphorylated by M1 stimulation. Because mPar3 is known as an axonal specifying molecule and to be regulated by phosphatidylinositol 3-kinase (PI3-kinase), the involvement of teneurin-2 and PI3-kinase in the M1 signal was studied. In teneurin-2-deficient cortical neurons, M1-induced axonal extension and PI3-kinase activation were significantly inhibited. In addition, treatment with PI3-kinase inhibitor also reduced M1-induced axonal extension. These results suggest that M1 induces axonal outgrowth through the teneurin-2-PI3-kinase cascade.

Amyloid beta-Peptides↗

PubMed2006

Withanoside IV and its active metabolite, sominone, attenuate Abeta(25-35)-induced neurodegeneration.

At the present, medication of dementia is limited to symptomatic treatments such as the use of cholinesterase inhibitors. To cure dementia completely, that is regaining neuronal function, reconstruction of neuronal networks is necessary. Therefore, we have been exploring antidementia drugs based on reconstructing neuronal networks in the damaged brain and found that withanoside IV (a constituent of Ashwagandha; the root of Withania somnifera) induced neurite outgrowth in cultured rat cortical neurons. Oral administration of withanoside IV (10 micromol/kg/day) significantly improved memory deficits in Abeta(25-35)-injected (25 nmol, i.c.v.) mice and prevented loss of axons, dendrites, and synapses. Sominone, an aglycone of withanoside IV, was identified as the main metabolite after oral administration of withanoside IV. Sominone (1 microM) induced axonal and dendritic regeneration and synaptic reconstruction significantly in cultured rat cortical neurons damaged by 10 microM Abeta(25-35). These data suggest that orally administrated withanoside IV may ameliorate neuronal dysfunction in Alzheimer's disease and that the active principle after metabolism is sominone.

Amyloid beta-Peptides↗

PubMed2006

Comparative study of chemical constituents of rhubarb from different origins.

A comparative study of the pharmacologically active constituents of 24 rhubarb samples, which were identified genetically as Rheum tanguticum, 3 intraspecies groups of R. palmatum and R. officinale, was conducted using reversed-phase high performance liquid chromatography (HPLC) methods. Thirty compounds belonging to anthraquinones, anthraquinone glucosides, dianthrones, phenylbutanones, stilbenes, flavan-3-ols, procyanidins, galloylglucoses, acylglucoses, gallic acid, and polymeric procyanidins were analyzed quantitatively. The drug samples derived from the same botanical source showed similar chromatographic profiles, and the comparable specific shape that appeared in the 10-directed radar graphs constructed on the basis of the results of quantitative analysis indicated the relationship between chemical constituent patterns and genetic varieties of rhubarb samples.

Anthracenes↗

PubMed2006

Development of a high performance liquid chromatographic method for systematic quantitative analysis of chemical constituents in rhubarb.

HPLC methods for the systematic determination of 30 compounds in Rhei Rhizoma (rhubarb) were developed. Using a combination of mobile phase gradient conditions and UV detection at 280 nm, all 30 compounds were separated satisfactorily with low detection limits (0.05-2 microg/ml). The developed methods provided a reliable calibration curve for each compound. By adopting these methods, the determination of 30 compounds in three kinds of rhubarb samples, derived from Rheum tanguticum, R. palmatum and R. officinale, was achieved. The constituent pattern of each rhubarb was clearly characterized through the quantitative composition of 30 major constituents of rhubarb.

Calibration↗

PubMed2005

Neuritic regeneration and synaptic reconstruction induced by withanolide A.

We investigated whether withanolide A (WL-A), isolated from the Indian herbal drug Ashwagandha (root of Withania somnifera), could regenerate neurites and reconstruct synapses in severely damaged neurons. We also investigated the effect of WL-A on memory-deficient mice showing neuronal atrophy and synaptic loss in the brain. Axons, dendrites, presynapses, and postsynapses were visualized by immunostaining for phosphorylated neurofilament-H (NF-H), microtubule-associated protein 2 (MAP2), synaptophysin, and postsynaptic density-95 (PSD-95), respectively. Treatment with A beta(25-35) (10 microM) induced axonal and dendritic atrophy, and pre- and postsynaptic loss in cultured rat cortical neurons. Subsequent treatment with WL-A (1 microM) induced significant regeneration of both axons and dendrites, in addition to the reconstruction of pre- and postsynapses in the neurons. WL-A (10 micromol kg(-1) day(-1), for 13 days, p.o.) recovered A beta(25-35)-induced memory deficit in mice. At that time, the decline of axons, dendrites, and synapses in the cerebral cortex and hippocampus was almost recovered. WL-A is therefore an important candidate for the therapeutic treatment of neurodegenerative diseases, as it is able to reconstruct neuronal networks.

Animals↗

PubMed2005

Effect of curcuma herbs on vasomotion and hemorheology in spontaneously hypertensive rat.

Curcuma herbs have a vasodilator effect. The effects of C. longa, which induces only endothelium-independent vasodilatation, and C. zedoaria, which induces both endothelium-dependent and -independent vasodilatation, were studied on vasomotion and hemorheology in spontaneously hypertensive rats. Spontaneously hypertensive eight-week-old male rats were assigned to five groups. For 12 weeks, the control group received standard chow. The 3%CL (C. longa) group received standard chow containing 3% (wt/wt) C. longa. The 1%CZ and 3%CZ (C. zedoaria) groups received standard chow containing 1% and 3% (wt/wt) C. zedoaria, respectively. The captoril group received standard chow and 100 mg/kg/day of captoril in drinking water. Blood pressure, vasomotion, hemorheology, etc. were examined. Systolic blood pressure of the 3%CZ and captoril groups decreased significantly as compared to the control group. Acetylcholine-induced endothelium-dependent relaxations of the 3%CZ and captoril groups were increased to a greater degree, significantly, than the control group. When testing xanthine oxidase-induced contraction, the 3%CZ group was significantly decreased as compared to the control group. Low shear stress of whole blood viscosity showed the 3%CL and 3%CZ groups to be decreased significantly compared to the control group. Thus, Curcuma herbs have hypotensive and protective effect on the endothelium in spontaneously hypertensive rats. Especially, C. zedoaria is more effective than C. longa, and its mechanism is thought to be related to a radical scavenging effect and improvement of hemorheology.

Animals↗

PubMed2005

Search for natural products related to regeneration of the neuronal network.

The reconstruction of neuronal networks in the damaged brain is necessary for the therapeutic treatment of neurodegenerative diseases. We have screened the neurite outgrowth activity of herbal drugs, and identified several active constituents. In each compound, neurite outgrowth activity was investigated under amyloid-beta-induced neuritic atrophy. Most of the compounds with neurite regenerative activity also demonstrated memory improvement activity in Alzheimer's disease-model mice. Protopanaxadiol-type saponins in Ginseng drugs and their metabolite, M1 (20-O-beta-D-glucopyranosyl-(20S)-protopanaxadiol), showed potent regeneration activity for axons and synapses, and amelioration of memory impairment. Withanolide derivatives (withanolide A, withanoside IV, and withanoside VI) isolated from the Indian herbal drug Ashwagandha, also showed neurite extension in normal and damaged cortical neurons. Trigonelline, a constituent of coffee beans, demonstrated the regeneration of dendrites and axons, in addition to memory improvement.

Alzheimer Disease↗

PubMed2004

Abeta(25-35)-induced memory impairment, axonal atrophy, and synaptic loss are ameliorated by M1, A metabolite of protopanaxadiol-type saponins.

We previously screened neurite outgrowth activities of several Ginseng drugs in human neuroblastoma, and demonstrated that protopanaxadiol (ppd)-type saponins were active constituents. Since ppd-type saponins are known to be completely metabolized to 20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol (M1) by intestinal bacteria when taken orally, M1 and ginsenoside Rb1, as a representative of ppd-type saponins, were examined for cognitive disorder. In a mouse model of Alzheimer's disease (AD) by Abeta(25-35) i.c.v. injection, impaired spatial memory was recovered by p.o. administration of ginsenoside Rb1 or M1. Although the expression levels of phosphorylated NF-H and synaptophysin were reduced in the cerebral cortex and the hippocampus of Abeta(25-35)-injected mice, their levels in ginsenoside Rb1- and M1-treated mice were almost completely recovered up to control levels. Potencies of the effects were not different between ginsenoside Rb1 and M1 when given orally, suggesting that most of the ginsenoside Rb1 may be metabolized to M1, and M1 is an active principal of ppd-type saponins for the memory improvement. In cultured rat cortical neurons, M1 showed extension activity of axons, but not dendrites. The axon-specific outgrowth was seen even when neuritic atrophy had already progressed in response to administration of Abeta(25-35) as well as in the normal condition. These results suggest that M1 has axonal extension activity in degenerated neurons, and improve memory disorder and synaptic loss induced by Abeta(25-35). M1 was shown to be effective in vitro and in vivo, indicating that Ginseng drugs containing ppd-type saponins may reactivate neuronal function in AD by p.o. administration.

Amyloid beta-Peptides↗

PubMed2004

Species identification from Ginseng drugs by multiplex amplification refractory mutation system (MARMS).

The multiplex amplification refractory mutation system (MARMS) was applied to the identification of 5 Panax species ( P. ginseng, P. japonicus, P. quinquefolius, P. notoginseng and P. vietnamensis). A set of specific primers, including 2-pair primers on chloroplast trnK gene and nuclear 18S rRNA gene regions, respectively, was designed and synthesized for each species on the basis of species-specific sequences of the 2 genes. By using 5 sets of specific primers, in turn, PCR amplifications were performed with total DNA extracted from 5 Panax species as template under appropriate condition, and each resulting product was detected by agarose gel electrophoresis. The results showed that two expected fragments, one from trnK gene and another from 18S rRNA gene regions, were observed simultaneously only when the set of species-specific primers encountered template DNA of the corresponding species. This assay could give more reliable results for identification of not only 5 Panax species but also corresponding Ginseng drugs by simultaneous detection of 4-site nucleotide differences on 2 completely different genes.

DNA Mutational Analysis↗

PubMed2004

Comparative study on triterpene saponins of Ginseng drugs.

A comparative study on the triterpene saponins of 47 samples of Ginseng drugs derived from 12 Panax taxa was conducted using a reverse-phase high-performance liquid chromatography (HPLC)method. Eleven ginsenosides, which represent 4 types of typical sapogenins, were chosen as standards for quantitative determination in order to characterize the chemical constituent pattern of each Ginseng drug and investigate the relationship between genetic varieties and chemical constituent pattern. The results showed that the ginsenoside compositions in Ginseng drugs of different origins were of considerable variability. Total saponin contents varied by 10-fold from the highest drug to the lowest one. Chikusetsu-ninjin derived from P. japonicus (Japan) was found to have the highest content (192.80 - 296.18 mg/g) and Ginseng from P. ginseng to be the lowest (5.78 - 15.63 mg/g). Two main groups (I and II) suggested by phytochemical data were clearly observed; group I mainly containing dammarane saponins consisted of P. ginseng, P. quinquefolius, P. notoginseng, P. vietnamensis and P. vietnamensis var. fuscidiscus; and group II containing a large amount of oleanolic acid saponins was com-posed of P.japonicus (apan), P. zingiberensis, P.japonicus (China),P. japonicus var. angustifolius, P. japonicus var. major, P. japonicus var. bipinnatifidus and P. stipuleanatus. The ratios of the subtotal of dammarane saponins to that of oleanolic acid saponins (D/0) were found to be > 1.9 and < 0.25 for groups I and II, respectively. The drug samples derived from the same botanical origin revealed similar constituent patterns, in other words, each Panaxtaxon showed its own characteristic chromatographic profile,which appeared in the specific shape of an 11-direction radar graph constructed on the basis of the result of quantitative analysis. Similarities of chemical constitution were seen among the closely phylogenetically-related taxa, including P. ginseng and P.quinquefolius, P. vietnamensis and P. vietnamensis var.fuscidiscus,P. japonicus (China) and its varieties were demonstrated, except P. japonicus (Japan) and P. zingiberensis.

Chromatography, High Pressure Liquid↗

PubMed2004

Phylogenetic analysis of the DNA sequence of the non-coding region of nuclear ribosomal DNA and chloroplast of Ephedra plants in China.

Twenty-four Ephedra plants belonging to 8 species grown in the northern and western parts of China were phylogenetically analyzed for their non-coding DNA sequences, internal transcribed spacers (ITSs) of nuclear ribosomal DNA as well as trnL intron and intergenic spacers between trnL and trnF (trnL/ trnF) of the chloroplast. Based on the ITS sequences, the 8 species could be divided into 3 groups: Group 1 (Ephedra intermedia, E. sinica, E. przewalskii), Group 2 (E. equisetina, E. monosperma, E. gerardiana), and Group 3 (E. likiangensis, E. minuta). The species classified into Group 1 grow mainly in the north, Group 3 in the south and Group 2 in the center, suggesting their genetic and geographic relationships. A specific primer set was designed to classify the 3 groups by routine PCR. Combined analysis of ITS and trnL/ trnF differentiated the 8 Ephedra species.

Cell Nucleus↗

PubMed2004

Application of single-nucleotide polymorphism analysis of the trnK gene to the identification of Curcuma plants.

We previously found that Curcuma plants and drugs derived from Curcuma longa, C. phaeocaulis, C. zedoaria, and C. aromatica could be identified by the nucleotide differences at two sites and the existence of a 4-base indel on trnK gene. In this paper, based on species-specific nucleotide sequences, the application of a new method, single-nucleotide polymorphism (SNP) analysis was investigated to identify Curcuma plants more conveniently. First, three types of reverse primer were synthesized in different lengths, 34 mer, 26 mer, and 30 mer, to anneal the template DNAs from each species at sites immediately upstream from substitution positions 177 and 645, and at the site including the 4-base insertion from 728 to 731, respectively. After single-base extension reaction of these primers using fluorescent-labeled ddNTPs and PCR products of the trnK gene region as template, the resulting products were detected using an ABI PRISM 310 Genetic Analyzer. The electrophoretogram showed three or two peaks at different positions depending on the 27 mer, 31 mer, and 35 mer product lengths. Each peak was derived from the incorporated fluorescent-labeled ddNMPs complementary to template nucleotides at positions 645, 724, and 177, respectively. C. phaeocaulis showed three peaks of ddCMP, ddAMP, and ddAMP. The other three species showed two peaks derived from 27 mer and 35 mer products: peaks of ddCMP and ddAMP in C. longa, those of ddCMP and ddTMP in C. zedoaria, and those of ddTMP and ddAMP in C. aromatica. Thus SNP analysis to identify four Curcuma plants was newly developed.

Curcuma↗

PubMed2004

Molecular analysis of Rheum species used as Rhei Rhizoma based on the chloroplast matK gene sequence and its application for identification.

Rhei Rhizoma (Dahuang in Chinese) is widely known as a purgative and antiinflammatory agent. In the Japanese Pharmacopoeia, Rhei Rhizoma is prescribed for four Rheum species, Rheum palmatum, R. tanguticum, R. officinale, and R. coreanum, while the first three species are prescribed for Dahuang in the Chinese Pharmacopoeia. Due to the morphologic similarity of the aerial parts and frequent occurrence of intermediate forms, the taxonomy of this genus and the correct identification of Rheum species and their derivative drugs are very difficult. To resolve taxonomic problems of the genus Rheum and develop an ultimate identification method for plants and drugs, molecular analysis of the chloroplast matK gene and nuclear 18S ribosomal RNA gene were performed on nine species. The sequence comparison of the matK gene revealed that most species had variable sequences not only inter- but also intraspecies. However, the specimens of the same species belonged to the same subclade in the phylogenetic tree constructed based on matK gene sequences, except for R. palmatum, in which specimens belonged to three subclades related to their production areas. The nucleotide differences at positions 587, 707, and 838 distinguished official species from others, while specific nucleotides at positions 367 and 937 became identification markers for R. palmatum, R. tanguticum, and R. officinale (or R. coreanum). Moreover, three groups of R. palmatum, each belonging to three subclades, were characterized by the nucleotides at positions 619, 769, 883, and 1061. By detecting marker nucleotides, the botanical origins of Rhei Rhizoma were determined.

Amino Acid Sequence↗

PubMed2004

Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and amplification refractory mutation system (ARMS) analyses of medicinally used Rheum species and their application for identification of Rhei Rhizoma.

Previously, we have determined marker nucleotides on the chloroplast matK gene to identify Rheum palmatum, R. tanguticum and R. officinale used as Rhei Rhizoma officially. In the present study, we further developed a convenient and efficient identification method on the basis of marker nucleotides with Amplification Refractory Mutation System analysis. On the basis of the nucleotide substitutions at positions 367 and 937 among the three species on the matK gene, at each position two kinds of reverse primers with complementary 3'-terminal nucleotides were designed. Upon PCR amplification using three sets of primers and template DNA from each species, one or two fragments (202 bp or/and 770 bp) were detected. As the resultant three fragment profiles were species-specific, the procedure enabled us to classify the botanic origins of 22 drug samples of Rhei Rhizoma.

Base Sequence↗

PubMed2004

New triterpenoid saponins from the roots of Sinocrassula asclepiadea.

Five new triterpenoid monodesmosides (sinocrassulosides I-V, 1-5) and six bisdesmosides (sinocrassulosides VI-XI, 6-11), in which 2-11 possess different acyl groups in the glycosidic moieties, were isolated from the roots of Sinocrassula asclepiadea FRANCH. Sinocrassulosides VI (4) and V (5) also contained a novel A-seco aglycone in their structures. All of the structures were determined on the basis of spectroscopic and physicochemical evidence.

Caryophyllaceae↗

PubMed2004

Simultaneous determination of triterpene saponins in ginseng drugs by high-performance liquid chromatography.

A HPLC method for the simultaneous determination of 11 triterpene saponins with four-type aglycones (protopanaxadiol, protopanaxatriol, ocotillol and oleanolic acid types) in Ginseng drugs was developed and validated. Using a gradient of acetonitrile and 10 mM K-phosphate buffer (pH 5.80) as the mobile phase and UV detection at 196 nm, more than 18 ginsenosides with different aglycones were separated satisfactorily within 60 min. The detection limits (signal/noise> or =3) were 0.1 microg for ginsenosides Rb1, Rc, Rd, Re and Rg1, chikusetsusaponin III, and notoginsenoside R2, 0.2 microg for gisenoside Ro and chikusetsusaponin IVa, 0.3 microg for chikusetsusaponin IV, and 3 microg for majonoside R2. The calibration curve of each saponin had a correlation coefficient close to 1. Intra- and interday precisions were less than 2.1% (n=5) and 3.3% (n=15), respectively. The recovery rates of extraction were in the range of 96.4-102.7% for all ginsenosides. By adopting this method, the determinations of 11 ginsenosides in three Ginseng drugs derived from Panax ginseng, Panax vietnamensis var. fuscidiscus and Panax japonicus (Japan) were achieved.

Calibration↗

PubMed2004

[Research of ginsenosides in kou zi qi using HPLC-MS-MS].

AIM: To analyze the ginsenosides in Kou zi qi (rhizomes of Panax japonicus C. A. Mey. var. major (Burkill) C. Y. Wu et K. M. Feng), and to supply evidences for chemotaxanology of Panax species and clinical uses of Kou zi qi. METHODS: The ginsenosides were isolated by HPLC, then the positive- and negative-ion API-MS/MS of constituents collected from HPLC were measured. RESULTS: Eight ginsenosides were identified as ginsenoside Re, ginsenoside Ro, chikuseksusaponins IV, IVa, notoginsenoside R2, ginsenosides Rb1, Rc and Rd, respectively, based on comparison of retention time with those of standards by HPLC, and analysis on their API-MS/MS data. Ginsenoside Ro and chikuseksusaponin IVa are the major components of Kou zi qi. CONCLUSION: This plant had a close relationship to P. stipuleanatus, P. zinginensis and P. japonicus var major; a relatively remote relationship to P. ginseng and P. quinquefolius, in a view of chemotaxanology. Ginsenoside Ro and chikuseksusaponin IVa might be the anti-inflammatory constituents of Kou zi qi.

Chromatography, High Pressure Liquid↗