Toshiyuki Atsumi

Naringenin suppresses macrophage infiltration into adipose tissue in an early phase of high-fat diet-induced obesity.

Obese adipose tissue is characterized by increased macrophage infiltration, which results in chronic inflammation in adipose tissue and leads to obesity-related diseases such as type 2 diabetes mellitus and atherosclerosis. The regulation of macrophage infiltration into adipose tissue is an important strategy for preventing and treating obesity-related diseases. In this study, we report that naringenin, a citrus flavonoid, suppressed macrophage infiltration into adipose tissue induced by short-term (14 days) feeding of a high-fat diet in mice; although naringenin did not show any differences in high-fat diet-induced changes of serum biochemical parameters in this short administration period. Naringenin suppressed monocyte chemoattractant protein-1 (MCP-1) in adipose tissue, and this effect was mediated in part through inhibition of c-Jun NH2-terminal kinase pathway. Naringenin also inhibited MCP-1 expression in adipocytes, macrophages, and a co-culture of adipocytes and macrophages. Our results suggest a mechanism by which daily consumption of naringenin may exhibit preventive effects on obesity-related diseases.

The relationship between growth of the aerial part and alkaloid content variation in cultivated Aconitum carmichaeli Debeaux

Processed root of aconite, Aconitum carmichaeli Debeaux—known as bushi in Japan—is indispensable for treating diseases among elderly persons in Japanese and Chinese traditional medicine. Its active component is bushi diester alkaloid (BDA), which consists of aconitine (ACO), mesaconitine (MES), hypaconitine (HYP), and jesaconitine (JES). Since an overdose of BDA results in severe side effects, the BDA content should be within safe limits. However, the BDA content of raw aconite root, even that produced by standard cultivation procedures, varies greatly. In this study, to clarify the cause of BDA variation, we examined the weight and BDA content of each part of cultivated A. carmichaeli: the aerial part, the mother tuberous root (MT), the daughter tuberous root (DT), and the rootlet (RL). We found the following positive relationships: between aerial part weight and DT weight, aerial part weight and BDA content in stem of apex, and BDA content in stem of apex and total BDA of DT attached to the plant. Furthermore, DT belonging to a higher weight group showed less BDA content variation. In addition, BDA of DT and those of MT and RL differ in both content and composition. In conclusion, it was suggested that the weight or the size of the aerial part was a good marker for monitoring BDA content and its variation in the tuberous root, and it was found to be desirable to prevent mixing MT and RL at harvest.

Hot Water Extract of Adzuki (Vigna angularis) Suppresses Antigen-Stimulated Degranulation in Rat Basophilic Leukemia RBL-2H3 Cells and Passive Cutaneous Anaphylaxis Reaction in Mice

The hot water extract of adzuki (HWEA), which is produced as a byproduct in the adzuki bean boiling process, has anti‐tumor, antioxidative, and anti‐diabetic activities. In this study, we fractionated HWEA to 4 fractions using stepwise gradient column chromatography with water and ethanol, and demonstrated the effects of each fraction on antigen (Ag)‐stimulated degranulation in rat basophilic leukemia RBL‐2H3 cells. The 40% ethanol eluate extract (EtEx.40) showed the strongest inhibition level of these fractions. To reveal the inhibitory mechanisms underlying degranulation by EtEx.40, we investigated intracellular reactive oxygen species (ROS) production, intracellular free Ca2+ concentration ([Ca2+]i), and early intracellular signaling pathways. Treatment with EtEx.40 markedly inactivated Lyn following Ag stimulation, resulting in the suppressions of intracellular elevation of [Ca2+]i and production of ROS. To identify the active compound in EtEx.40, we isolated 7 flavonoids from EtEx.40 and calculated their inhibition levels on Ag‐stimulated degranulation. These flavonoids inhibited degranulation by about 25–60%. We further examined the in vivo effects of HWEA or EtEx.40 using a passive cutaneous anaphylaxis (PCA) reaction. Both extracts strongly suppressed the PCA reaction. These findings suggest that HWEA and/or EtEx.40 are beneficial for alleviating type I allergic symptoms. Copyright

Difference in cultivation characteristics and genetic polymorphism between Chinese and Japanese strains of Wolfiporia cocos Ryvarden et Gilbertson (Poria cocos Wolf)

Poria, a dried sclerotium of Wolfiporiacocos Ryvarden et Gilbertson (Polyporaceae) has been used as a crude drug in both Chinese and Japanese (Kampo) traditional medicines. Recently, cultivated products of Chinese Poria strains have accounted for most of the market, while the cultivation of Japanese Poria strains has not been successful. Aiming to determine the relationship between the differences in cultivation characteristics and genetic polymorphism, we conducted a field cultivation experiment, a rot test, and rapid amplification of polymorphic DNA (RAPD) analysis of Poria strains collected from China and Japan: 3 Chinese and 7 Japanese strains. In field cultivation, although there was no marked inferiority of Japanese strains to Chinese ones in either mycelium propagation or the rate of sclerotium formation, Chinese strains formed whiter sclerotia with a mean size more than twice that of Japanese ones. Representatives of Chinese and Japanese strains, Yunnan and Kaimondake, respectively, were tested for wood-rotting ability. More wood was utilized and the wood color was darker in trials of the Yunnan strain. Amplifications of total DNA of these 10 fungal strains with 2 primers, PC-6 and PC-11, in RAPD analysis showed a difference in the amplicon profile between Japanese and Chinese strains, suggesting differences in their genetic background.

Novel phenolic glycosides, adenophorasides A–E, from Adenophora roots

Five novel phenolic glycosides, adenophorasides A (1), B (2), C (3), D (4), and E (5), were isolated from commercial Adenophora roots, together with vanilloloside (6), 3,4-dimethoxybenzyl alcohol 7-O-β-d-glucopyranoside (7), and lobetyolin (8). The structures of the new compounds (1–5) were characterized as 4-hydroxy-3-methoxyphenylacetonitrile 4-O-β-d-glucopyranoside (1), 4-hydroxy-3-methoxyphenylacetonitrile 4-O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranoside (2), 4-hydroxy-3-methoxyphenylacetonitrile 4-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (3), 4-hydroxyphenylacetonitrile 4-O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranoside (4), and 4-hydroxy-3-methoxybenzyl alcohol 4-O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranoside (5), respectively, by means of spectroscopic and chemical analyses.

Diversity in aconitine alkaloid profile of Aconitum plants in Hokkaido contrasts with their genetic similarity.

Aconite tuber is a representative crude drug for warming the body internally in Japanese Kampo medicine and Chinese traditional medicine. The crude drug is used in major prescriptions for the aged. Varieties of Aconitum plants are distributed throughout the Japanese Islands, especially Hokkaido. With the aim of identifying the medicinal potential of Aconitum plants from Hokkaido, 107 specimens were collected from 36 sites in the summer of 2011 and 2012. Their nuclear DNA region, internal transcribed spacer (ITS), and aconitine alkaloid contents were analyzed. Phylogenic analysis of ITS by maximum parsimony analysis showed that the majority of the specimens were grouped into one cluster (cluster I), separated from the other cluster (cluster II) consisting of alpine specimens. The aconitine alkaloid content of the tuberous roots of 76 specimens showed 2 aspects—specimens from the same collection site showed similar aconitine alkaloid profiles, and cluster I specimens from different habitats showed various alkaloid profiles. Environmental pressure of each habitat is presumed to have caused the morphology and aconitine alkaloid profile of these genetically similar specimens to diversify.

The development of new molecular tools containing a chemically synthesized carbohydrate ligand for the elucidation of carbohydrate roles via photoaffinity labeling: carbohydrate-protein interactions are affected by the structures of the glycosidic bonds and the reducing-end sugar.

Photoaffinity labeling technology is a highly efficient method for cloning carbohydrate-binding proteins. When the carbohydrate probes are synthesized according to conventional methods, however, the reducing terminus of the sugar is opened to provide an acyclic structure. Our continued efforts to solve this problem led to the development of new molecular tools with an oligosaccharide structure that contains a phenyldiazirine group for the elucidation of carbohydrate-protein interactions. We investigated whether carbohydrate-lectin interactions are affected by differences in the glycosidic formation and synthesized three types of molecular tools containing Galp-GlcpNAc disaccharide ligands and a photoreactive group (1, 2, 3). Photoaffinity labeling validated the recognition of the new ligand by different glycosidic bonds. Photoaffinity labeling also demonstrated that both the reducing end sugar and non-reducing end sugar recognized the Erythrina cristagalli agglutinin.

Survey on the Original Plant Species of Crude Drugs Distributed as Cynanchi Wilfordii Radix and Its Related Crude Drugs in the Korean and Chinese Markets

Cynanchi Wilfordii Radix (CWR) is used in Korea as a substitute for Polygoni Multiflori Radix (PMR), which is a crude drug traditionally used in East Asian countries. Recently, the use of Cynanchi Auriculati Radix (CAR) in place of PMR and CWR has emerged a major concern in the Korean market. In Japan, PMR is permitted to be distributed as a pharmaceutical regulated by the Japanese Pharmacopoeia 17th edition (JP17). Although CWR and CAR have not traditionally been used as medicines, CWR was recently introduced as a health food. The distribution of unfamiliar CWR-containing products could lead to the misuse of original species for PMR and CWR like in Korea. To prevent this situation, the original species of plant products distributed as PMR, CWR, and CAR in the Korean and Chinese markets were surveyed and identified by their genes and components. The results revealed that all two PMR in the Korean market were misapplied as CAR, and that CAR was incorrectly used in eight of thirteen products distributed as CWR in both markets. As PMR is strictly controlled by JP17, the risk of mistaking PMR for CWR and CAR would be low in Japan. In contrast, the less stringent regulation of health food products and the present situation of misidentification of CWR in the Korean and Chinese markets could lead to unexpected health hazards. To ensure the quality and safety of crude drugs, it is important to use the information about the genes and components of these crude drugs.

Synthesis of a new glycosphingolipid, neurosporaside, from Neurospora crassa.

The glycosphingolipid neurosporaside (α-D-Glcp-(1 → 2)-β-D-Galp-(1 → 6)-β-D-Galp-(1 → 6)-β-D-Galp-(1 →)-Cer) occurs in Neurospora crassa. We attempted to synthesize neurosporaside by block synthesis (route A) and linear synthesis (route B). Oligosaccharide derivatives were synthesized using trimethylsilyltrifluoromethanesulfonate and N-iodosuccinimide/trifluoromethane sulfonic acid as promoters. The target tetrasaccharide could not be attained via route A, but route B showed potential: glycosidic bonds (β-D-Galp-(1 → 6)-β-D-Galp-(1 → 6)-β-D-Galp) were formed stereoselectively, leading to the synthesis of glycosphingolipid 2.

A Novel Clerodane Diterpene from Vitex cofassus

New clerodane diterpene, 16-hydroxy-pentandralactone (1) and known diterpene acuminolide (2) were isolated from the methanol extract of Vitex cofassus leaves. The chemical structure and the absolute configuration of 1 were determined by MS, NMR and electron circular dichroism (ECD) experiments. The isolated compounds were evaluated for their antiproliferative activities against a panel of human tumor cell lines, including a multidrug-resistant (MDR) cell line. Both compounds showed potent antiproliferative activities against all the tested cell lines with IC50 values of 5.4-11.4 µM. Their effects on cell viability were also tested using vascular endothelial growth factor (VEGF)-stimulated human umbilical vein endothelial cells (HUVECs). Compound 1 inhibited VEGF-stimulated HUVEC proliferation in a dose-dependent manner. Based on these results, compound 1 could be a candidate for antitumor agent and inhibitor of angiogenesis.