Tsuneo Namba

Active-oxygen scavenging activity of traditional nourishing-tonic herbal medicines and active constituents of Rhodiola sacra.

The active-oxygen scavenging activity of 70 traditional herbal medicines used in China and Japan as nourishing tonics were evaluated by electron spin resonance (ESR) technique, in order to evaluate their effectiveness for anti-aging and to search for new active-oxygen scavengers from natural resources. Most of the 70 herbal medicines showed scavenging activity with various intensities. Areca catechu (methanol extract), Dendrobium plicatile (methanol extract), Juglans regia (water extract), Paeonia lactiflora (methanol extract), Psychotria serpens (water and methanol extracts), Rhodiola sacra (water and methanol extracts) and Uncaria rhynchophylla (water extract) especially showed strong scavenging activity against superoxide anion radical (*O2-), while J. regia (water and methanol extracts), Morus alba (water extract) and Schisandra chinensis (water extract) revealed strong scavenging activity against hydroxyl radical (HO*). In addition, the active-oxygen scavenging activities of 19 compounds isolated from R. sacra were also examined, and hydroquinone (1), caffeic acid (3), protocatechuic acid (6), gallic acid (7), (-)-epigallocatechin 3-O-gallate (8), 3-O-galloylepigallocatechin-(4beta-->8)-epigallocatechin+ ++ 3-O-gallate (10), heterodendrin (17) and gallic acid 4-O-beta-D-glucopyranoside (19) were found to show mild or strong inhibitory activity against superoxide anion radical (*O2-), while 4-hydroxybenzoic acid (2), 3, 4-hydroxycinnamic acid (4), 6-8 and 19 inhibited hydroxyl radical (OH*). These active-oxygen scavengers may contribute, to different extents, to their anti-aging action.

Antiviral traditional medicines against herpes simplex virus (HSV-1), poliovirus, and measles virus in vitro and their therapeutic efficacies for HSV-1 infection in mice.

One hundred forty-two kinds of traditional medicines, which have been historically used in China, Indonesia, and Japan, were examined for the antiviral activity of their hot water (HW) extracts against herpes simplex virus type 1 (HSV-1), poliovirus type 1, and measles virus by plaque reduction assay. Thirty-two, 55, and 30 HW-extracts of them showed anti-HSV-1, antipoliovirus, and anti-measles virus activities, respectively. Among the 32 HW-extracts with anti-HSV-1 activity, 3 HW-extracts had anti-HSV-1 activity alone and the others showed anti-HSV-1 activity with anti-poliovirus and/or anti-measles virus activities. The 32 HW-extracts were further examined for their therapeutic efficacies of HSV-1 infection in mice. The mice were infected cutaneously with HSV-1 and HW-extracts were orally administered three times daily. Twelve HW-extracts, currently used for the treatment of various diseases other than viral infection, were found to be significantly effective in limiting the development of skin lesions and/or in prolonging the mean survival times of HSV-1-infected mice. These results suggested that 12 of 142 HW-extracts that exhibited therapeutic efficacy in an animal infection model were possible candidates for anti-HSV-1 traditional medicine.

Efficacy of traditional herbal medicines in combination with acyclovir against herpes simplex virus type 1 infection in vitro and in vivo

Traditional herbal medicines have been safely used for the treatment of various human diseases since ancient China. We selected 10 herbal extracts with therapeutic antiherpes simplex virus type 1 (HSV-1) activity. Among these, Geum japonicum Thunb., Rhus javanica L., Syzygium aromaticum (L.) Merr. et Perry, or Terminalia chebula Retzus showed a stronger anti-HSV-1 activity in combination with acyclovir than the other herbal extracts in vitro. When acyclovir and/or a herbal extract were orally administered at doses corresponding to human use, each of the 4 combinations significantly limited the development of skin lesions and/or prolonged the mean survival times of infected mice compared with both acyclovir and the herbal extract alone (P < 0.01 or 0.05). These combinations were not toxic to mice. They reduced virus yields in the brain and skin more strongly than acyclovir alone and exhibited stronger anti-HSV-1 activity in the brain than in the skin, in contrast to acyclovir treatment by itself. Combinations of acyclovir with historically used herbal medicines showed strong combined therapeutic anti-HSV-1 activity in mice, especially reduction of virus yield in the brain.

Anti-inflammatory effects of emodin from ventilago leiocarpa.

Emodin, a major component of the AcOEt and CHCl3 fractions from Ventilago leiocarpa Bunge (Rhamnaceae), was isolated. It exhibited apti-inflammatory effect on carrageenan-induced edema in rats.

Acteoside inhibits apoptosis in D-Galactosamine and lipopolysaccharide-induced liver injury

We assessed the effect of acteoside, a naturally occurring antioxidative phenylethanoid, on hepatic apoptosis and the subsequent liver failure induced by D-Galactosamine (D-GalN) and lipopolysaccharide (LPS). A co-administration of D-GalN (700 mg/kg) and LPS (35 microg/kg) to mice evoked typical hepatic apoptosis characterized by DNA fragmentation and apoptotic body formation, resulting in fulminant hepatitis and lethality of mice. Pre-administration of acteoside at 10 or 50 mg/kg subcutaneously at 12 and 1 h prior to D-GalN/LPS intoxication significantly inhibited hepatic apoptosis, hepatitis and lethality. Tumor necrosis factor-alpha (TNF-alpha) secreted from LPS-stimulated macrophages is an important mediator of apoptosis in this model. Acteoside showed no apparent effect on the marked elevation of serum TNF-alpha, but it partially prevented in vitro TNF-alpha (100 ng/ml)-induced cell death in D-GalN (0.5 mM)-sensitized hepatocytes at the concentrations of 50, 100 and 200 microM. These results indicated that D-GalN/LPS-induced hepatic apoptosis can be blocked by an exogenous antioxidant, suggesting the involvement of reactive oxygen intermediates (ROIs) in TNF-alpha-dependent hepatic apoptosis.

Biochemical changes related to aging in the senescence-accelerated mouse

Several biochemical parameters reflecting the degree of senescence were compared between senile-prone (P) and resistant (R) strains of male senescence-accelerated mouse (SAM) at 11 to 12 months of age. Plasma testosterone in SAM-P amounted to half the concentration in SAM-R. In the liver and brain of SAM-P, the content of malondialdehyde (MDA) and the activity of monoamine oxidase B (MAO-B) were significantly higher than those in SAM-R. Moreover, large amounts of fluorescent lipofuscin were detected in the SAM-P liver. Compared with SAM-R, both membrane and cytosolic fractions from the SAM-P liver contained small amounts of protein and showed less activity of superoxide dismutase (SOD). The present findings suggest that the male SAM-P rapidly acquires biochemical changes which are considered to be part of the normal aging process.

Hepatoprotective effects of emodin from Ventilago leiocarpa

A major component of ethyl acetate (EtOAc) and chloroform (CHCl3) fractions of Ventilago leiocarpa Bunge (Rhamnaceae), emodin, was isolated and exhibited hepatoprotective effects on carbon tetrachloride (CCl4) as well as D-galactosamine (D-GalN)-induced liver damage. The histopathological examination also clearly showed that emodin reduced lymphocyte cells, Kupffer cells, ballooning degeneration, cell necrosis and hyaline degeneration on CCl4 and D-galactosamine-induced tests.

Constituents of cimicifugae rhizoma II. Isolation and structures of new cycloartenol triterpenoids and related compounds from Cimicifuga foetida L

Abstract Neutral constituents of Cimicifuga foetida L. were examined. Eight new triterpenoids and three new trinor-triterpenoids were isolated from the rhizoma of C. foetida L. (Ranunculaceae) along with six known compounds and their structures were determined by the use of 2D NMR techniques and chemical methods.

Hydrolysis of glycyrrhizin to 18β-glycyrrhetyl monoglucuronide by lysosomal β-D-glucuronidase of animal livers

Abstract Glycyrrhizin (GL), a main constituent of liquorice, was hydrolysed to 18β-glycyrrhetic acid mono-β- d -glucuronide (GAMG, glycyrrhetyl monoglucuronide) by rat liver homogenate, and the hydrolytic activity was localized in the lysosomes among the same subcellular fractions as acid β- d -glucuronidase activity (p-nitrophenyl β- d -glucuronide (pNPG)-hydrolysing activity). Rat liver lysosomeshydrolysed GAMG to 18β-glycyrrhetic acid (GA) at only 30% rate compared with the rate of GL to GAMG. GA was also produced slowly from GL after time lag by the lysosomes. Thus, GL seems to be first hydrolysed to GAMG, which was successively hydrolysed slowly to GA. GL-hydrolysing activity was released together with acid β- d -glucuronidase activity from the lysosomes by sonication. Both activities from the sonicated lysosomes were eluted coincidentally on Sephacryl S-300 and butyl-Toyopearl 650M column chromatography, indicating that both activities are exhibited by the same enzyme. Moreover, GL-hydrolysing activity was inhibited strongly with d -saccharic acid 1,4-lactone, a specific inhibitor of β- d -glucuronidases of various origins. pH optimum of GL-hydrolysing activity was found to be 5.6, different from that (less than 4.0) of pNPG-hydrolysing activity. Km for GL was found to be 2 × 10−5 M. Although hepatic lysosomes from mouse and cattle hydrolysed GAMG to GA similarly to those from rat, the hydrolysis of GAMG was not detected in lysosomes of human and porcine livers. Accordingly, lysosomal β- d -glucuronidases from human and porcine livers converted GL to GAMG only.

New neolignans and lignans from the aril of Myristica fragrans

Abstract Eight neolignans and five lignans were isolated from mace, the aril of Myristica fragrans , and their structures were determined by spectroscopic methods as erythro -2-(4″-allyl-2″,6″-dimethoxyphenoxy)-1-(3′,4′,5′-trimethoxyphenyl)propan-1,3-diol ( 1b ), threo -2-(4″-allyl-2″-methoxyphenoxy)-1-(4′-hydroxy-3′-methoxyphenyl) propan-1-ol ( 2a ), threo -1-(4′-hydroxy-3′-methoxyphenyl)-2-(2″-methoxy-4″-(1‴ ( E )-propenyl) phenoxy) propan-1-ol ( 3a ), its erythro form ( 3b ), threo -1-(4′-hydroxy-3′-methoxyphenyl)-1-methoxy-2-(2″-methoxy-4″-(1‴-( E )-propenyl)phenoxy)-propane ( 4a ), its erythro form ( 4b ), fragransol-A ( 5 ), fragransol-B ( 6 ), fragransin D 1 ( 7 ), fragransin D 2 ( 8 ), fragransin D 3 ( 9 ), fragransin E 1 ( 10 ) and the known compound austrobailignan-7 ( 11 ).