Biomedical subjects

Katsuko Komatsu

Publications and source records attributed to Katsuko Komatsu.

33 records · Page 2Linked to original sources

PubMed2003

Repair of amyloid beta(25-35)-induced memory impairment and synaptic loss by a Kampo formula, Zokumei-to.

Although Zokumei-to (ZMT), a Kampo formula, has been used for postapopletic sequelae such as paralysis and logopathy, only few studies of this drug have been carried out. We hypothesized that ZMT may affect neuronal plasticity and investigated whether or not this drug is capable of improving learning impairment and synaptic loss observed in patients with Alzheimer's disease (AD). Amyloid beta(25-35) [Abeta(25-35)] (4.7 nmol) was intracerebroventricularly injected into ddY mice (male, 6 weeks old). Fourteen days after the injection, mice were given ZMT extract (500 mg/kg/day) per os for 15 days. In a memory acquisition test, the Abeta(25-35)-injected mice required more time to master this task than did mice in the saline- or reverse peptide Abeta(35-25)-treated groups. ZMT-treated mice shortened escape latencies during trial days 3-5, but not significantly. Three days after the last drug treatment, a retention test was performed. Following ZMT, the number of crossings over a platform was significantly decreased in Abeta(25-35)-injected mice compared with those in the control groups. However, ZMT-treated mice showed complete recovery of this number. Although Abeta(25-35) injection decreased synaptophysin expression in the cerebral cortex and the hippocampus, ZMT treatment significantly increased the level of expression of synaptophysin up to the control level. Donepezil hydrochloride (DNP, 0.5 mg/kg/day, p.o.) clinically used for AD had no effect on memory retention and synaptophysin levels. Abeta(25-35)-induced neuronal loss was not observed in any region of the brain. The present results suggest that memory impairment and synaptic loss in AD patients may be improved by treatment with ZMT, even after such impairment has already progressed.

Alzheimer Disease↗

PubMed2003

Prenylated flavonoids from Moghania philippinensis.

Five prenylated flavonoids, 8-(1,1-dimethylallyl)genistein (1), 5,7,3',4'-tetrahydroxy-2',5'-di(3-methylbut-2-enyl)isoflavone (2), 5,7,3'-trihydroxy-2'-(3-methylbut-2-enyl)-4',5'-(3,3-dimethylpyrano)isoflavone (3), (2R)-5,2',4'-trihydroxy-8,5'-di(3-methylbut-2-enyl)-6,7-(3,3-dimethylpyrano)flavanone (4a) and (2S)-5, 2', 4'-trihydroxy-8,5'-di(3-methylbut-2-enyl)-6,7-(3,3-dimethylpyrano)flavanone (4b), were isolated from the roots of Moghania philippinensis. The structures of these compounds were determined on the basis of spectroscopic and chemical means.

Fabaceae↗

PubMed2003

Phylogenetic relationship in the genus Panax: inferred from chloroplast trnK gene and nuclear 18S rRNA gene sequences.

Chloroplast trnK gene and nuclear 18S rRNA gene sequences of 13 Panax taxa, collected mainly from Sino-Japanese floristic region, were investigated in order to construct phylogenetic relationship and to assist taxonomic delimitation within this genus. The length of trnK gene sequence varied from 2537 bp to 2573 bp according to the taxa, whereas matK gene sequences, embedded in the intron of trnK gene, were of 1512 bp in all taxa. Species-specific trnK/ matK sequence provided much insight into phylogeny and taxonomy of this genus. 18S rRNA gene sequences were of 1808 or 1809 bps in length, only 9 types of 18S rRNA sequences were observed among 13 taxa. Parsimony and neighbor-joining analyses of the combined data sets of trnK-18S rRNA gene sequences yielded a well-resolved phylogeny within genus Panax, where three main clades were indicated. P. pseudoginseng and P. stipuleanatus formed a sister group located at a basal position in the phylogenetic tree, which suggested the relatively primitive position of these two species. Monophyly of P. ginseng, P. japonicus (Japan) and P. quinquefolius, which are distributed in northern parts of Asia or America, was well supported (Northern Clade). The remaining taxa distributed in southern parts of Asia formed a relatively large clade (Southern Clade). The taxonomic debated taxa traditionally treated as subspecies or varieties of P. japonicus or P. pseudoginseng showed various nucleotide sequences, but all fell into one cluster. It might suggest these taxa are differentiated from a common ancestor and are in a period of high variation, which is revealed not only on morphological appearance, but also on molecular divergence. By comparing trnK and 18S rRNA gene sequences among 13 Panax taxa, a set of valuable molecular evidences for identification of Ginseng drugs was obtained.

Cell Nucleus↗

PubMed2003

Effects of curcuma drugs on vasomotion in isolated rat aorta.

The effectiveness of Curcuma drugs against "Oketsu" and the differences in their efficacy were evaluated by examining their vasomotional effects as one index. Since nitric oxide (NO) is the relaxation factor of vascular smooth muscle and also an inhibitor of platelet aggregation in blood vessels, substances showing NO-dependent relaxation are thought to be effective in improving Oketsu. In this study, five Curcuma drugs derived from Curcuma longa, C. kwangsiensis, C. phaeocaulis, C. wenyujin, and C. zedoaria were used. Methanol extracts exhibited intense effects on relaxation in rings precontracted by prostaglandin F(2alpha) (PGF(2alpha)) despite pretreatment with and without N(G)-nitro-l-arginine methyl ester (L-NAME) as an inhibitor of NO synthesis. The maximal activities were approximately 80% at 10(-3) g/ml. From these methanol extracts, curcumin and eight sesquiterpenes were isolated. Since all these compounds showed NO-independent relaxation effects with almost the same intensities, the relaxation effects of Curcuma drugs can be estimated by the total amounts of curcumin and sesquiterpenes. Polysaccharides, the main constituents of methanol-insoluble compounds of water extracts, in contrast, showed contraction effects; only polysaccharides in C. zedoaria showed NO-dependent relaxation as well as contraction. All water extracts showed relaxation effects as sum of the methanol-soluble compounds-induced relaxation and polysaccharides-induced contraction. Therefore, all Curcuma drugs tested in the present study can be effective for vasodilation. Moreover, the drug derived from C. zedoaria has potential to cure Oketsu with its various acting points.

Animals↗

PubMed2003

Wild ginseng grows in Myanmar.

Ginseng, the underground parts of plants of Panax species, has been used in oriental traditional medicine for centuries. Unfortunately, because of extensive exploitation over thousands of years, the natural source of these species has been almost exhausted. Recently, we have found a wild ginseng growing in Myanmar. Here, by a combination of chemical composition study and gene sequence analysis, we unambiguously demonstrate that the wild ginseng is actually P. zingiberensis, commonly known as ginger ginseng. This ginseng was an indigenous to the southwestern China. However, now it is seriously threatened to brink of extinction and is put on the highest level of protection in China. Therefore, an appropriate protection measure is highly recommended to preserve this valuable resource, since this Myanmar ginseng might turn out to be the last P. zingiberensis, which could ever be seen in the planet.

Base Sequence↗

PubMed2003

Molecular identification of six medicinal Curcuma plants produced in Sichuan: evidence from plastid trnK gene sequences.

AIM: To establish a rapid and simple molecular identification method for six medicinals: Curcuma: C. longa, C. phaeocaulis, C. sichuanensis, C. chuanyujin, C. chuanhuangjiang, and C. chuanezhu in Sichuan Province. METHODS: A molecular approach (trnK nucleotide sequencing) was used in this study. RESULTS: The sequenced entire chloroplast trnK gene region spanned 2,699-2,705 bp. The matK gene (an intron embodied in trnK gene) sequence and the intron spacer region of the trnK gene have great diversity within these six medicinal Curcuma species. There were six single bases substitutions between trnK coding region and matK region, the 9-bp deletion and 4-bp or 14-bp insertion repeat at some sites of matK region in each taxon. CONCLUSION: These relatively variable sequences were potentially informative in the identification for these six Curcuma species at the DNA level.

Base Sequence↗

PubMed2002

Axon- or dendrite-predominant outgrowth induced by constituents from Ashwagandha.

We previously reported that the methanol extract of Ashwagandha (roots of Dunal) induced dendrite extension in a human neuroblastoma cell line. In this study, we found that six of the 18 compounds isolated from the methanol extract enhanced neurite outgrowth in human neuroblastoma SH-SY5Y cells. Double immunostaining was performed in rat cortical neurons using antibodies to phosphorylated NF-H as an axonal marker, and to MAP2 as a dendritic marker. In withanolide A-treated cells, the length of NF-H-positive processes was significantly increased compared with vehicle-treated cells, whereas, the length of MAP2-positive processes was increased by withanosides IV and VI. These results suggest that axons are predominantly extended by withanolide A, and dendrites by withanosides IV and VI.

Animals↗

PubMed2002

Sodium tanshinone IIA sulfonate derived from Danshen (Salvia miltiorrhiza) attenuates hypertrophy induced by angiotensin II in cultured neonatal rat cardiac cells.

Sodium tanshinone IIA sulfonate (STS), a derivative of tanshinone IIA, is isolated from the root of Salvia miltiorrhiza known as "Danshen." Although injection of S. miltiorrhiza extract and STS is used widely and successfully in clinics in China for treating cardiovascular diseases, the exact mechanism for its therapeutic basis is poorly understood. The present study was undertaken to characterize the effect of STS on angiotensin II-induced hypertrophy on cultured myocytes and cardiac fibroblasts (nonmyocytes) prepared from neonatal rat hearts. Angiotensin II (1nM) increased protein synthesis and surface area in myocytes, and DNA synthesis and cell number in nonmyocytes, respectively. Exposure of the myocytes to STS (5-80 microM) for 24hr produced no cytotoxicity as evaluated by the 3-[4,5-dimethylthiazol-2-yl]-3,5-diphenylformazan (MTT) assay. Although STS (10 microM) alone showed no effect on the growth of cultured cardiac cells, it markedly suppressed angiotensin II-induced enlargement of cells and [3H]phenylalanine incorporation, proceeding from the induction of immediate early gene (c-jun) expression in myocytes. Furthermore, STS prevented the rise in [Ca(2+)](i) mediated by angiotensin II in myocytes. In contrast, STS (10 microM) was without effect on hyperplasia and c-jun expression induced by angiotensin II in nonmyocytes. The present in vitro findings support the interpretation that STS is a substance that may be beneficial in protecting the myocardium against hypertrophy.

Angiotensin II↗

PubMed2002

Screening of Chinese and Mongolian herbal drugs for anti-human immunodeficiency virus type 1 (HIV-1) activity.

Water and methanol extracts of 30 Chinese and Mongolian medicinal plants were tested for their human immunodeficiency virus type-1 (HIV-1) inhibitory activity. Of the 60 extracts, 23 showed anti-HIV activity. Bioassay-guided fractionation of one of the most active extracts, the methanol extract of the root tuber of Stephania cepharantha, led to the isolation of two alkaloids, aromoline and FK-3000 as potent inhibitory substances. They completely inhibited the cytopathic effects of HIV-1 on MT-4 cells at 31.3 and 7.8 microg/mL, respectively.

Alkaloids↗

PubMed2002

Dammarane-type triterpene saponins from Panax japonicus.

Six new dammarane-type saponins (1-6), together with 11 known saponins (7-17), were isolated from Ye-Sanchi, the underground part of Panax japonicus collected in the South of Yunnan Province, China. Their structures were elucidated by chemical and spectroscopic means.

China↗

PubMed2002

Dammarane-type Saponins from Panax japonicus and their neurite outgrowth activity in SK-N-SH cells.

Four new dammarane-type saponins (1-4), named yesanchinosides G-J, together with nine ginsenosides (5-13) were isolated from Ye-Sanchi, the underground part of Panax japonicus collected in the south of Yunnan Province, China. Their structures were elucidated on the basis of spectroscopic and chemical methods. Ginsenosides Rb(1) and Rb(3) and notoginsenosides R(4) (6) and Fa (7) showed significant neurite outgrowth enhancing activities in human neuroblastoma SK-N-SH cells.

Drugs, Chinese Herbal↗

PubMed2002

Sequence analysis of Chinese and Japanese Curcuma drugs on the 18S rRNA gene and trnK gene and the application of amplification-refractory mutation system analysis for their authentication.

The botanical origins of Chinese and Japanese Curcuma drugs were determined to be Curcuma longa, C. phaeocaulis, the Japanese population of C. zedoaria, C. kwangsiensis, C. wenyujin, and C. aromatica based on a comparison of their 18S rRNA gene and trnK gene sequences with those of six Curcuma species reported previously. Moreover, to develop a more convenient identification method, amplification-refractory mutation system (ARMS) analysis of both gene regions was performed on plants. The ARMS method for the 18S rRNA gene was established using two types of forward primers designed based on the nucleotide difference at position 234. When DNAs of four Curcuma species were used as templates, PCR amplification with either of the two primers only generated a fragment of 912 base pairs (bp). However, when DNAs of the purple-cloud type of C. kwangsiensis and C. wenyujin were used, PCR amplifications with both primers unexpectedly generated the fragment, suggesting that these two were heterozygotes. The ARMS method for the trnK gene was also established using a mixture of four types of specific reverse primers designed on the basis of base substitutions and indels among six species, and common reverse and forward primers. C. phaeocaulis or the Chinese population of C. zedoaria, the Japanese population of C. zedoaria or the purple-cloud type of C. kwangsiensis, the pubescent type of C. kwangsiensis or C. wenyujin, and C. aromatica were found to show specific fragments of 730, 185, 527 or 528, and 641 or 642 bp, respectively. All species including C. longa also showed a common fragment of 897-904 bp. Using both ARMS methods, together with information on producing areas, the identification of Curcuma plants was achieved. Moreover, the ARMS method for the trnK gene was also useful for authentication of Curcuma drugs.

Curcuma↗

PubMed2002

Withanolide derivatives from the roots of Withania somnifera and their neurite outgrowth activities.

Five new withanolide derivatives (1, 9-12) were isolated from the roots of Withania somnifera together with fourteen known compounds (2-8, 13-19). On the basis of spectroscopic and physiochemical evidence, compounds 1 and 9-12 were determined to be (20S,22R)-3 alpha,6 alpha-epoxy-4 beta,5 beta,27-trihydroxy-1-oxowitha-24-enolide (1), 27-O-beta-D-glucopyranosylpubesenolide 3-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside (withanoside VIII, 9), 27-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosylpubesenolide 3-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside (withanoside IX, 10), 27-O-beta-D-glucopyranosylpubesenolide 3-O-beta-D-glucopyranoside (withanoside X, 11), and (20R,22R)-1 alpha,3 beta,20,27-tetrahydroxywitha-5,24-dienolide 3-O-beta-D-glucopyranoside (withanoside XI, 12). Of the isolated compounds, 1, withanolide A (2), (20S,22R)-4 beta,5 beta,6 alpha,27-tetrahydroxy-1-oxowitha-2,24-dienolide (6), withanoside IV (14), withanoside VI (15) and coagulin Q (16) showed significant neurite outgrowth activity at a concentration of 1 microM on a human neuroblastoma SH-SY5Y cell line.

Disaccharides↗

PubMed2002

Axonal and dendritic extension by protopanaxadiol-type saponins from ginseng drugs in SK-N-SH cells.

Extension of axons and dendrites in neurons may compensate for and repair damaged neuronal networks in the dementia brain. To find out drugs capable of regenerating the neuronal network, we focused on several herbal drugs belonging to the genus Panax, kinds of Ginseng, and investigated neurite outgrowth activity of their extracts and compounds. We found that the methanol extracts of Ginseng (root of P. ginseng), Notoginseng (root of P. notoginseng) and Ye-Sanchi in Chinese (rhizome of a relative to P. vietnamensis) increased neurite outgrowth in SK-N-SH cells. The protopanaxadiol-type saponins, ginsenosides Rb(1) and Rb(3), and notoginsenosides R(4) and Fa isolated from Ye-Sanchi extract extended neurites, while protopanaxatriol-, ocotillol- and oleanane-type saponins had no effect on the neurite outgrowth. The percentage of cells with multipolar neurites and number of varicosities were intensely high in cells treated with the methanol extract of Ye-Sanchi as well as ginsenosides Rb(1) and Rb(3), and notoginsenosides R(4) and Fa. Both phosphorylated NF-H-expressing neurites and MAP2-expressing ones were extended by treatment with those saponins and the extract. Especially, longer neurites were mainly positive for phosphorylated NF-H. These results suggest that protopanaxadiol-type saponins enhance axonal and dendritic formation activity.

Axons↗

PubMed2002

[A novel approach to quality evaluation of root of Scutellaria baicalensis by DPPH free radical scavenging].

OBJECTIVE: To develop a simple, reliable approach for evaluating the quality of Huangqin (Scutellaria baicalensis). METHOD: To determine the DPPH free radical scavenging activity and assay of four bioactive components: baicalin, baicalein, wogonin and wogonin-7-O-glucuronide by HPLC. RESULT: The correlative relationship between DPPH free radical scavenging activity and baicalin content was obtained. CONCLUSION: Bioassay of DPPH free radical scavenging activity could be used as one of the methods for quality evaluation of Chinese drug Huangqin.

Biphenyl Compounds↗