Abietane-type diterpenoids from the roots of Caryopteris mongolica and their cholinesterase inhibitory activities.

Eleven abietane-type diterpenoids and two known abietanes were isolated from the roots of Caryopteris mongolica, and their structures were characterized. The absolute configurations at C-5 and C-10 were determined from the NMR data, including from the nuclear Overhauser effect and CD spectra, and the absolute configuration of C-16 in the hydroxypropyl group was determined via a modified Mosher's method. Furthermore, the previously unknown absolute configuration of the C-15 of cyrtophyllone B was determined to be in an R-configuration using X-ray crystallography. To estimate the preventive effects of the isolates for neurodegenerative disease development, their inhibitory activities against acetylcholinesterase (AChE) from human erythrocytes and butyrylcholinesterase (BChE) from horse serum were evaluated.

Investigation into hippocampal nerve cell damage through the mineralocorticoid receptor in mice.

Stress­associated neuropsychiatric disease is associated with glucocorticoid levels; however, the behavior of mineralocorticoid receptors (MR) under conditions of stress remain to be elucidated. Steroid receptors in the brain are classified into glucocorticoid receptors (GR) and/or MR, exhibiting a difference in affinity for corticosteroids. The hippocampus is one of the most stress­susceptible regions in the brain. In the present study, it was investigated whether the two steroid receptors affect hippocampal neuron damage. The effect of fludrocortisones (FD) on hippocampal neurons caused by FD­containing cholesterol pellets subcutaneously embedded in the backs of mice (FD pellet group, 80 mg cholesterol and 20 mg FD) was investigated. A significant extension of the tail length by ~2.22 fold was observed in the FD pellet group compared with that in the control group as elucidated via the comet assay. Cytotoxicity (pyknosis and degranulation) and DNA fragmentation due to the death of nerve cells were observed using Kluver­Barrera staining and terminal deoxynucleotidyl transferase dUTP nick end labeling. Compared with the sham group mice, hippocampal neuron damage was observed in the adrenalectomized mice and the damage was suppressed by the combinatorial use of spironolactone, which suggested MR­induced hippocampal neuron damage. In conclusion, the present study clearly indicated a regional difference in vulnerability and/or sensitivity to corticosteroids. MR sensitivity to corticosteroids was high in the CA3 region and pyramidal cells of the hippocampus, which may therefore be vulnerable to corticosteroids. Thus, it is clearly suggested that MR function is important in the stress response.

An antibacterial ortho-quinone diterpenoid and its derivatives from Caryopteris mongolica.

To identify antibacterial components in traditional Mongolian medicinal plant Caryopteris mongolica, an ortho-quinone abietane caryopteron A (1) and three its derivatives caryopteron B-D (2-4) were isolated from the roots of the plant together with three known abietanes demethylcryptojaponol (5), 6α-hydroxydemethyl cryptojaponol (6), and 14-deoxycoleon U (7). The chemical structures of these abietane derivatives were elucidated on the basis of spectroscopic data. Compounds 1-4 had C-13 methylcyclopropane substructures, and 2-4 had a hexanedioic anhydride ring C instead of ortho-quinone in 1. The stereochemistry of these compound was assumed from NOE spectra and ECD Cotton effects. Compounds 1 and 5-7 showed antibacterial activities against the Gram-positive bacteria Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, and Micrococcus luteus, being 1 the more potent.

Cholinesterase-inhibitory diterpenoids and chemical constituents from aerial parts of Caryopteris mongolica.

A diterpenoid diglucoside (12,19-di-O-ß-D-glucopyranosyl-11-hydroxyabieta-8,11,13-triene-19-one), isoscutellarein 7-O-[ß-D-xylopyranosyl-(1→2)]-ß-D-glucopyranoside, isoscutellarein 7-O-[α-L-rhamnopyranosyl-(1→2)]-ß-D-glucopyranoside, hypolaetin 7-O-[6″-O-(p-E-coumaroyl)]-ß-D-glucopyranoside, hypolaetin 7-O-[6″-O-(E-caffeoyl)]-ß-D-glucopyranoside, and 15 known compounds were isolated from aerial parts of the Mongolian medicinal plant Caryopteris mongolica. The cholinesterase-inhibitory activities of the constituents were estimated. The abietane diterpenoids (12-O-demethylcryptojaponol and 6α-hydroxydemethylcryptojaponol) showed potent inhibitory activity against acetylcholinesterase from human erythrocytes and electric eel, and against butyrylcholinesterase from horse serum.

Effect of natural flavonoids, stilbenes and caffeic acid oligomers on protein glycation.

The aim of the present study was to identify the inhibitory activity of natural flavonoids, stilbenes and caffeic acid oligomers on protein glycation. Antioxidant activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity. The production of 3-deoxyglucosone (3-DG) and advanced glycation end products (AGEs) by glycation reactions were determined by high-performance liquid chromatography and fluorescence, respectively. Certain flavonoids, stilbenes and caffeic acid oligomers prevented AGE production and the IC50 values of the compounds were compared. These examined compounds are assumed to suppress AGE generation by inhibiting the increase in 3-DG production through a specific unknown mechanism in the early phase of the Maillard reaction, by inhibiting the generation of active oxygen in the later phase and by suppressing the progression of the reaction. Regular, daily consumption of these compounds in the form of a food or extract is expected to aid in the prevention or inhibition of non-enzymatic amino acid glycation in the living body, which is possibly associated with aging, diabetic complications, arteriosclerotic diseases and Alzheimer's disease, and they may also be effective agents in cosmetics promoting anti-aging.

Chemical constituents of aerial parts and roots of Pycnanthemum flexuosum.

An extract of whole plants of Pycnanthemum flexuosum showed an inhibitory effect on hyaluronidase activity. From an 80% acetone extract of aerial parts, 3-[(3E)-4-phenylbut-3-enoylamino]propionic acid, 3-O-ß-D-glucuronopyranosyl-echinocystic acid 28-O-ß-D-xylopyranosyl-(1→3)-[3,4-diacetyl-ß-D-xylopyranosyl-(1→4)]-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl ester, vanillic acid 1-O-[(5-O-syringoyl)-ß-D-apiofuranosyl]-(1→2)-ß-D-glucopyranoside, and (4S,5R)-4-hydroxy-5-phenyl-tetrahydrofuran-2-one were isolated together with 30 known compounds. Six known compounds were isolated from an 80% acetone extract of roots, and eritrichin was revealed as a hyaluronidase inhibitor in P. flexuosum.

Monoterpene glycosides, phenylpropanoids, and acacetin glycosides from Dracocephalum foetidum.

Chemical investigation of the acetone extract from the aerial parts of the Mongolian medicinal plant Dracocephalum foetidum resulted in the isolation of three limonene glycosides, a caffeic acid trimer, four rosmarinic acid glucosides, and five acacetin acyl glycosides, together with 13 known natural products. The chemical structures of all of the compounds were determined by spectroscopic analyses. Among these compounds three showed hyaluronidase inhibitory activity. In addition, one other compound showed stronger 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity than the positive control Trolox, whereas three other compounds demonstrated a similar activity to that of Trolox.

Diastereomers of lithospermic acid and lithospermic acid B from Monarda fistulosa and Lithospermum erythrorhizon.

Monardic acids A (1) and B (2), which are (7R,8R) diastereomers of lithospermic acid (LA) and lithospermic acid B, respectively, were isolated from Monarda fistulosa. A (7S,8R) isomer (3) of LA was also isolated from this plant, and a (7R,8S) isomer (7) of LA was obtained from Lithospermum erythrorhizon. The absolute configuration of 1 was confirmed by analysis of its hydrolysates, 7-epiblechnic acid and 2R-3-(3,4-dihydroxyphenyl)-2-hydroxypropanoic acid. The configuration in the dihydrobenzofuran moieties of 2, 3, and 7 was extrapolated by using the phenylglycine methyl ester method and a Cotton effect at approximately 250-260 nm in their electronic circular dichroism spectra. Diastereomers (1-3 and 7) displayed moderate hyaluronidase inhibitory and histamine release inhibitory activities.

Phytochemical constituents of Mongolian traditional medicinal plants, Chamaerhodos erecta and C. altaica, and its constituents prevents the extracellular matrix degradation factors.

Activity-guided isolation of the n-butanol fraction of Chamaerhodos erecta and water soluble fraction of C. altaica resulted in the isolation of 39 compounds, including new compounds identified as 4,5-dihydroxybenzaldehyde-3-O-ß-D-glucopyranoside (1) from C. erecta and quercetin-3-O-ß-D-glucuronopyranosyl-4'-O-ß-D-glucopyranoside (2) from C. altaica. A total of 37 other compounds were identified based on physico-chemical properties and spectroscopic data. Antioxidative activity was evaluated using a DPPH radical-scavenging method, hyaluronidase inhibitory activity, and advanced glycation end products production inhibitory activity of isolated compounds. Some flavonols (4, 6, 9-11, 14, 15), catechins (18, 19), an amino acid (20), a lignan glucoside (23), and tannins (29-39) exhibited potential a free radical scavenging activity while the new compound (1) showed weak activity. A catechin (18) and some of the tannins (32, 33, 35, 36, 38) had moderate hyaluronidase inhibitory activity. Some of flavonoids and tannins prevented advanced glycation end products production, and the IC50 of compounds 3, 9, 14-16, 33, 34, 36, 38, and 39 were determined.

Flavone tetraglycosides and benzyl alcohol glycosides from the Mongolian medicinal plant Dracocephalum ruyschiana.

From an extract of the aerial parts of Dracocephalum ruyschiana, five new flavone tetraglycosides, five new benzyl alcohol glycosides, and 19 known compounds were isolated. The tetraglycosides contain a 7-O-ß-d-glucopyranosyl-(1→2)-ß-d-glucopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→6)]-ß-d-glucopyranosyl moiety. The benzyl alcohol glycosides had acyl groups on their glycosyl or aglycone moieties. The compounds were tested for antioxidant activity using DPPH. Although the new compounds were not active, phenylpropanoylquinic acid derivatives were revealed as radical scavengers in D. ruyschiana.

Lipase inhibitory and LDL anti-oxidative triterpenes from Abies sibirica.

A methanol extract of Abies sibirica Ladeb, a Mongolian medicinal plant, had an inhibitory effect on both lipase activity in mouse plasma and LDL anti-oxidative activity, which are preventative factors for arteriosclerosis. The extract was fractionated by silica gel column chromatography and its active constituents were sought. From lipid soluble fractions, 20 terpenoids including seven hitherto unknown triterpenes were isolated. The latter triterpenes had either a γ-lactone ring with a lactol or a derivative thereof. Their chemical structures were determined by spectroscopic methods. The lipase inhibitory activity and LDL anti-oxidative activity of these compounds were evaluated. Some constituents (either lipase inhibitory or LDL anti-oxidative activities) had moderate inhibitory activities.

Triterpene saponins from Clethra barbinervis and their hyaluronidase inhibitory activities.

An extract of Clethra barbinervis with an inhibitory effect on hyaluronidase activity was fractionated guided by the results of an assay. From the active fractions, seven new triterpene saponins (1-4, 6-8) and a new lignan glycoside (14) were isolated together with 14 known compounds (5, 9-13, 15-22). Some of the saponins (2, 3, 9) were revealed as hyaluronidase inhibitors similar to epicatechin (17).

Hyaluronidase inhibitors from Keiskea japonica.

An extract of Keiskea japonica MIQ. showed an inhibitory effect on hyaluronidase activity. From the extract, four new phenylpropanoids, two new maltol glycosides, two new monoterpene glycosides, and two new phenolic compounds were isolated together with 19 known compounds. Among these constituents, two phenylpropanoids and a flavone glucuronide were revealed as hyaluronidase inhibitors.

Extensive screening for herbal extracts with potent antioxidant properties.

This paper summarizes our research for herbal extracts with potent antioxidant activity obtained from a large scale screening based on superoxide radical (O(2) (•-)) scavenging activity followed by characterization of antioxidant properties. Firstly, scavenging activity against O(2) (•-) was extensively screened from ethanol extracts of approximately 1000 kinds of herbs by applying an electron spin resonance (ESR)-spin trapping method, and we chose four edible herbal extracts with prominently potent ability to scavenge O(2) (•-). They are the extracts from Punica granatum (Peel), Syzygium aromaticum (Bud), Mangifera indica (Kernel), and Phyllanthus emblica (Fruit). These extracts were further examined to determine if they also scavenge hydroxyl radical ((•)OH), by applying the ESR spin-trapping method, and if they have heat resistance as a desirable characteristic feature. Experiments with the Fenton reaction and photolysis of H(2)O(2) induced by UV irradiation demonstrated that all four extracts have potent ability to directly scavenge (•)OH. Furthermore, the scavenging activities against O(2) (•-) and (•)OH of the extracts of P. granatum (peel), M. indica (kernel) and P. emblica (fruit) proved to be heat-resistant.The results of the review might give useful information when choosing a potent antioxidant as a foodstuff. For instance, the four herbal extracts chosen from extensive screening possess desirable antioxidant properties. In particular, the extracts of the aforementioned three herbs are expected to be suitable for food processing in which thermal devices are used, because of their heat resistance.

Hyaluronidase inhibitory rosmarinic acid derivatives from Meehania urticifolia.

Nine new phenylpropanoids, rashomonic acids A-D (1-4) and meehaniosides A-E (5-9), along with four known compounds were isolated from Meehania urticifolia. The structure of each new compound was elucidated based on the results of spectroscopic analyses. Compounds 3-8 showed moderate hyaluronidase inhibitory activity with IC(50) values of 183-1049 µM.

New phenolic compounds from Meehania urticifolia.

A new phenylethanoid glycoside, rashomoside A (1), a new phenolic glucoside, rashomoside B (2), and a new shikimic acid derivative (3) were isolated from Meehania urticifolia together with 12 known flavones (4-15), three known phenylethanoid glycosides (16-18), and 13 other compounds (19-31). The structure of each of these compounds was elucidated based on the results of spectroscopic analysis.

A lipase inhibitor monoterpene and monoterpene glycosides from Monarda punctata.

An 80% acetone extract of Monarda punctata showed an inhibitory effect on lipase activity in isolated mouse plasma in vitro and carvacrol was obtained as the active constituent. It had an IC50 value of 4.07 mM invitro and suppressed elevations in blood triacylglycerol levels in olive oil-loaded mice. Furthermore, from the whole plant, 22 compounds were isolated. Six monoterpene glycosides, a flavone glucuronide, and other known compounds were identified based on the results of spectroscopic analyses.

Cyclic spermidine alkaloids and flavone glycosides from Meehania fargesii.

The dried whole plant of Meehania fargesii (H. LéV.) C. Y. WU is utilized as an antipyretic and antidote for poison in China. Water soluble fractions, obtained from an 80% acetone extract of the whole plant, showed hyaluronidase inhibitory activity. From these fractions, hyaluronidase inhibitors were isolated along with two new spermidine alkaloids (meefarnines A and B), four new flavone glycosides (fargenins A-D), and 10 known compounds. The structure of each was elucidated by spectroscopic methods.

Hyaluronidase inhibitors from Takuran, Lycopus lucidus.

Takuran is a traditional herbal medicine that is produced from the herbal plant Lycopus lucidas TURCZ. (Lamiaceae). Takuran is used as a treatment for diseases in women. From Takuran, four new phenylpropanoids along with 18 known compounds were isolated, and their structures were elucidated by spectroscopic analyses. Five phenylpropanoids isolated from the plant showed hyaluronidase inhibitory activity comparable to that of rosmarinic acid.

A Kampo Medicine, Boi-ogi-to, Inhibits Obesity in Ovariectomized Rats.

In women facing menopause, end of menstrual activity is accompanied by lower levels of estrogen and gradual weight gain. Postmenopausal weight gain sounds an alarm for women's health and may lead to hyperlipidemia, a lipid increase and glucose intolerance. These phenomena are connected to lifestyle-related diseases such as hypertension, type II diabetes mellitus, arteriosclerosis and metabolic syndrome, making it essential to prevent weight gain in women. A Kampo medicine, Boi-ogi-to, is traditionally used to treat obese conditions, but the mechanism has not yet been investigated. In this experiment, we tested the antiobesity properties of Boi-ogi-to in ovariectomized rats by measuring changes of serum cytokine levels and adipocytokines in fat cells. After treatment with this extract for 6 weeks (20-week-old rats), we found that there was a significant weight decrease in rats treated with Boi-ogi-to as compared with that in the control group. Serum tumor necrosis factor (TNF)-α levels increased significantly in a dose-dependent manner. Gene expression of adipose tissue in uterus also dose dependently showed a significant increase of TNF-α levels, suggesting that secretion of TNF-α by fat cells might play a role in the ability of Boi-ogi-to to inhibit weight gain. While peroxisome proliferators-activated receptor-γ and adiponectin levels did not show a significant difference as compared with those in the control, levels of mRNA expression showed a tendency to increase dose dependently. Resistin did not show any significant change. These results suggest that Boi-ogi-to might be useful for the prevention of obesity that occurs in women with reduction of estrogen.