Publications by authors named "Ryota Tsuchihashi"

Ipomoea alba L. (Convolvulaceae) is an annual vine native to tropical America that is cultivated primarily for ornamental purposes. Its seeds are used in traditional medicine as a laxative, and young shoots are consumed as food.

View Article and Find Full Text PDF

During the screening of novel chemotherapeutic candidates from plants against adult T-cell leukaemia/lymphoma (ATL), we found that extracts of plants in the Solanaceae, Annonaceae, Apocynaceae, and Rutaceae families showed anti-proliferative activity in the MT-1 and MT-2 cell lines. We have isolated active compounds from these plants in the present research because Cupressaceae plants showed potent anti-proliferative activity in the cell lines. We attempted to isolate the active compounds from the leaves of .

View Article and Find Full Text PDF

Resin glycosides are characteristic of plants of the Convolvulaceae family and are well-known purgative ingredients in crude drugs, such as Rhizoma Jalapae, Orizaba Jalapa Tuber, and Pharbitidis Semen, which are used in traditional medicine and derived from plants belonging to this family. Isolated resin glycosides have demonstrated diverse biological activities, including antibacterial, ionophoric, anti-inflammatory, antiviral, and multidrug-resistance-modulating properties, as well as cytotoxicity against cancer cells. These compounds consist of hydroxyl fatty acid oligoglycosides (glycosidic acids), with portions of the saccharide moieties acylated with some organic acids to form the core structure.

View Article and Find Full Text PDF

Resin glycosides act as laxatives in crude drugs derived from plants of the Convolvulaceae family. These compounds have exhibited antibacterial, ionophoric, anti-inflammatory, antiviral, and multidrug resistance-modulating properties, as well as cytotoxicity against cancer cells. This study investigated the organic acid, hydroxyl fatty acid, monosaccharide, and glycosidic acid components of the crude resin glycoside fraction obtained from the methanol extract of Ipomoea alba L.

View Article and Find Full Text PDF

Ipomoea muricata (L.) Jacq. seeds (Convolvulaceae) are used as a traditional laxative and carminative medicine.

View Article and Find Full Text PDF

Adult T-cell leukemia/lymphoma (ATL) is a malignancy of mature peripheral T-lymphocytes caused by human T-cell leukemia virus type I (HTLV-I). There are an estimated 5-20 million HTLV-1-infected individuals worldwide. Conventional chemotherapeutic regimens used against other malignant lymphomas have been administered to patients with ATL, but the therapeutic outcomes of acute and lymphoma-type ATL remain extremely poor.

View Article and Find Full Text PDF

The alkaline hydrolysis of the crude resin glycoside fraction from the leaves and stems of the plant Calystegia japonica Choisy (Convolvulaceae) yielded organic acid and glycosidic acid fractions. The organic acid fraction was esterified with p-bromophenacyl bromide to obtain p-bromophenacyl 2R-methyl-3R-hydroxybutyrate (1) and p-bromophenacyl (E)-2-methylbut-2-enoate (2). By treating the glycosidic acid fraction with trimethylsilyldiazomethane-hexane, seven new methyl esters of glycosidic acids, namely calyjaponic acid A methyl ester (3) calyjaponic acid B methyl ester (5), calyjaponic acid C methyl ester (6), calyjaponic acid D methyl ester (7), calyjaponic acid E methyl ester (8), calyjaponic acid F methyl ester (9), and calyjaponic acid G methyl ester (10), were isolated along with one known ester (4).

View Article and Find Full Text PDF

Two new resin glycosides, muricatins XII () and XIII (), were isolated from the crude resin glycoside fraction of the seeds of (L.) Jacq. (Convolvulaceae), along with three known ones, muricatins V (), VI (), and IX ().

View Article and Find Full Text PDF
Article Synopsis
  • - The study screened extracts from the Cupressaceae family for anti-cancer properties and found significant anti-proliferative effects on adult T-cell leukemia/lymphoma cells (MT-1 and MT-2).
  • - Researchers isolated 32 compounds, including lignans, terpenoids, and flavonoids, determining their structures using spectroscopic analysis, and discovered that lignans were the most effective in inhibiting cell growth.
  • - Findings suggest that specific structural features, like trans-lactone linkages in lignans and ketone moieties in diterpenes, enhance anti-cancer activity, indicating that these compounds could be potential treatments for adult T-cell leukemia/lymphoma.
View Article and Find Full Text PDF

Four new resin glycosides with macrolactone structures (jalapins), namely, calyhedins VII ()-X (), were isolated from the rhizomes of Wall. (Convolvulaceae). The structures of - were determined based on spectroscopic data.

View Article and Find Full Text PDF

Six previously undescribed resin glycosides, calyhedins I-VI, were isolated from the rhizomes of Calystegia hederacea Wall., which are the first genuine resin glycosides isolated from C. hederacea.

View Article and Find Full Text PDF

In the course of our screening program for novel chemotherapeutic candidates from plants against adult T-cell leukemia/lymphoma, the extracts of Asclepias curassavica L. showed potent activity against MT-1 and MT-2 cells. Therefore, we attempted to isolate their active components.

View Article and Find Full Text PDF

Two new glycosidic acids, calyhedic acids E () and F (), were isolated from the glycosidic acid fraction afforded by alkaline hydrolysis of the crude resin glycoside fraction obtained from whole plants of Wall. Compounds and were characterised as 11-hydroxyhexadecanoic acid 11--β-D-glucopyranosyl-(1→6)--β-D-glucopyranosyl-(1→6)--β-D-glucopyranosyl-(1→3)-[-α-L-rhamnopyranosyl-(1→2)]--β-D-glucopyranosyl-(1→2)-β-D-quinovopyranoside and an isomer of , in which the 11-hydroxyhexadecanoyl residue of was replaced by a 12-hydroxyhexadecanoyl residue, respectively, on the basis of spectroscopic data.

View Article and Find Full Text PDF

Resin glycosides are well known as the purgative ingredients, which are characteristic of convolvulaceous plants. Calystegia hederacea Wall. is a perennial herbaceous vine that is widespread throughout India and East Asia.

View Article and Find Full Text PDF

Two new triterpene glycosides, 24-deoxyoxytrogenin 3-O-α-L-rhamnopyranosyl (1→2)[β-D-glucopyranosyl]-β-D-galactopyranosyl (1→2)-β-D-glucuronopyranoside and sophoradiol 3-O-α-L-rhamnopyranosyl (1→2)-β-D-glucuronopyranosyl (1→2)-β-D-glucuronopyranoside with four known glycosides were isolated from a Chinese natural medicine, the roots of Uraria crinita (L.) DESV. Their structures were determined by chemical and spectral methods.

View Article and Find Full Text PDF

Rationale: Cannabis is a widely used illicit substance. ∆-tetrahydrocannabinol (THC), the major psychoactive component of cannabis, is known to cause catalepsy in rodents. Recent studies have shown that vasopressin V1a and V1b receptors are widely distributed in the central nervous system and are capable of influencing a wide variety of brain functions such as social behavior, emotionality, and learning and memory.

View Article and Find Full Text PDF

During the course of our studies towards the identification of promising chemotherapeutic candidates from plants against two human T-cell lymphotropic virus type I-infected T-cell lines (MT-1 and MT-2), we screened 17 extracts from 9 rutaceous plants against MT-1 and MT-2 cells. The extracts from the aerial parts and roots of Boenninghausenia japonica, as well as the leaves and roots of Ruta graveolens showed potent antiproliferative effects. After activity-guided fractionation, we isolated 44 compounds from two rutaceous plants, including three new compounds (1-3), which were classified into 26 coumarin analogs (13 coumarins, 8 furanocoumarins, 4 dihydrofuranocoumarins and one dihydropyranocoumarin), 15 alkaloid analogs (7 quinolone alkaloids, 4 acridone alkaloids, 3 furanoquinoline alkaloids and one tetrahydroacridone alkaloid) and 3 flavonoid glycosides.

View Article and Find Full Text PDF

Adult T-cell leukemia/lymphoma (ATL) is a malignancy of mature peripheral T lymphocytes caused by human T-cell lymphotropic virus type 1 (HTLV-1). There are an estimated 5 million to 20 million HTLV-1-infected individuals worldwide; their lifetime risk of developing ATL is 3-5 %, and high HTLV-1 proviral loads have been shown to be an independent risk factor. Although conventional chemotherapeutic regimens used against other malignant lymphomas have been administered to ATL patients, the prognosis is often poor.

View Article and Find Full Text PDF

Adult T-cell leukemia/lymphoma (ATL) is a malignancy of mature peripheral T lymphocytes caused by human T-cell lymphotropic virus type I (HTLV-I). In our previous paper, 214 extracts from 162 plants were screened to elucidate the anti-proliferative principles against HTLV-I-infected T-cell lines. In this study, 245 extracts from 182 plants belonging to 61 families were further tested against two HTLV-I-infected T-cell lines (MT-1 and MT-2).

View Article and Find Full Text PDF

Adult T-cell leukemia/lymphoma (ATL) is an incurable peripheral T-cell malignancy caused by human T-cell lymphotropic virus type I. In our preceding paper, 214 extracts from 162 plants were screened to elucidate the antiproliferative principles against ATL cell lines. Several withanolides were isolated and the structure-activity relationships (SAR) examined.

View Article and Find Full Text PDF

Adult T-cell leukemia/lymphoma (ATL) is a peripheral T-cell malignancy caused by human T-cell lymphotropic virus type I (HTLV-1). Clinical manifestations of ATL range from smoldering to chronic, lymphoma and acute subtypes. Patients with acute and lymphoma-type ATL require therapeutic intervention.

View Article and Find Full Text PDF

Plumbagin (PL; 5-hydroxy-2-methyl-1, 4-naphthoquinone) is an important secondary metabolite, mainly produced in the Plumbago zeylanica L. (Plumbaginaceae). A single-chain variable fragment (scFv) antibody, fusion of the variable regions of the heavy chain and light chain of immunoglobulin against PL (PL-scFv) was expressed by Bac-to-Bac Baculovirus Expression System using Spodoptera frugiperda (Sf9) insect cells and characterized to investigate potential use of PL-scFv as a tool for plant immunomodulation.

View Article and Find Full Text PDF

Pueraria candollei (White Kwao Khuer) is a medicinal plant containing puerarin (8-C-glucosyl-4',7-dihydroxyisoflavone) and its aglycone, daidzein, as major isoflavonoids used for its rejuvenating and estrogenic effects. In order to analyze these isoflavonoids, an enzyme-linked immunosorbent assay (ELISA) was developed using polyclonal antibody (PAb) against puerarin. Puerarin was conjugated with bovine serum albumin (BSA) to be used as an immunogen for production of PAb from a rabbit.

View Article and Find Full Text PDF

The Pueraria flowers, Puerariae Flos [Puerariae Lobatae Flos (the flowers of P. lobata) and Puerariae Thomsonii Flos (the flowers of P. thomsonii)], have been used as crude drugs to counteract the overconsumption of alcohol in Japan and China.

View Article and Find Full Text PDF

A fluorescent single-domain antibody (fluobody), a fusion protein of a green fluorescent protein extracted from Aequorea coerulescens (AcGFP), a mutant that has been codon-optimized for mammalian expression, and a single-chain variable fragment antibody (scFv), against plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone; PL) was successfully constructed and expressed in Escherichia coli. The expressed fluobody was purified, refolded, and characterized to develop a speedy, simple, and sensitive fluorescence-linked immunosorbent assay (FLISA) for the determination of PL. In this study, two kinds of fluobody containing PL-scFv at the N-terminus of AcGFP (N fluobody) or the C-terminus of AcGFP (C fluobody) were constructed with flexible amino acid linker (Gly(4)Ser)(2) between PL-scFv and AcGFP for comparative purposes.

View Article and Find Full Text PDF