Melanogenesis stimulation in murine B16 melanoma cells by Kava (Piper methysticum) rhizome extract and kavalactones.

Melanogenesis stimulation activity of aqueous ethanolic extracts obtained from several different parts of five Piper species, namely Piper longum, P. kadsura, P. methysticum, P. betle, and P. cubeba, were examined by using cultured murine B16 melanoma cells. Among them, the extract of P. methysticum rhizome (Kava) showed potent stimulatory effect on melanogenesis as well as P. nigrum leaf extract. Activity-guided fractionation of Kava extract led to the isolation of two active kavalactones, yangonin (2) and 7,8-epoxyyangonin (5), along with three inactive kavalactones, 5,6-dehydrokawain (1), (+)-kawain (3) and (+)-methysticin (4), and a glucosylsterol, daucosterin (6). 7,8-Epoxyyangonin (5) showed a significant stimulatory effect on melanogenesis in B16 melanoma cells. Yangonin (2) exhibited a weak melanogenesis stimulation activity.

Melanogenesis stimulation in murine b16 melanoma cells by umberiferae plant extracts and their coumarin constituents.

Melanogenesis stimulation activities of seven ethanolic extracts obtained from Umbelliferae plants used as Chinese crude drugs, namely the roots of Angelica dahurica BENTH. et HOOK., A. biserrata SHEN et YUAN, Notopterygium incisum TING, Heracleum lanatum MICHX., and H. candicans WALL., and the fruits of Cinidium monnieri (L.) CUSSON and C. formosanum YABE, were examined by using cultured murine B16 melanoma cells. Among them, the extract (5, 25 microg/ml) of H. lanatum showed a potent stimulatory effect on melanogenesis with significant enhancement of cell proliferation in a dose-dependent manner. The melanogenesis stimulatory effects of sixteen coumarins (1-16) isolated from the seven Umbelliferae crude drugs were also examined. Among them, linear-furocoumarins [psoralen (1), xanthotoxin (2), bergapten (3), and isopimpinellin (4)] and angular-furocoumarin [sphondin (13)] exhibited potent melanogenesis stimulation activity. From the view point of structure-activity relationships, it may be assumed that a linear-furocoumarin ring having a hydrogen and/or methoxyl group at 5 and 8 positions such as 1, 2, 3 and 4 was preferable for the melanogenesis stimulation activity. The introduction of a prenyl group into the furocoumarin ring was disadvantageous. Coumarin derivatives having a simple coumarin ring were inactive.

Studies on palauan medicinal herbs. II. Activation of mouse macrophages RAW 264.7 by Ongael, leaves of Phaleria cumingii (Meisn.) F. Vill. and its acylglucosylsterols.

The extract of Ongael [leaves of Phaleria cumingii (MEISN.) F. VILL.], a Palauan medicinal herb, enhanced an in vitro phagocytic activity of mouse macrophages RAW 264.7 cells (RAW 264.7). Activity-guided fractionation of the Ongael extract by the in vitro phagocytosis assay using RAW 264.7 led to the isolation of a mixture of acylglucosylsterols (1) as an active constituent along with other inactive constituents, tetracosanol and mangiferin. On the basis of chemical modifications and spectral analyses, the compound 1 was deduced to be a mixture of the known 3-O-(6-O-acyl-beta-D-glucosyl)-beta-sitosterols, the acyl moiety being mainly palmitoyl (57%), oleoyl (12%) and alpha-linolenoyl (12%) with small amount of stearoyl (7%) and linoleoyl (4%).

Melanogenesis stimulation in murine B16 melanoma cells by Piper nigrum leaf extract and its lignan constituents.

A methanolic extract from the leaves of Piper nigrum L. showed a significant stimulatory effect on melanogenesis in cultured murine B16 melanoma cells. Activity-guided fractionation of the methanolic extract led to the isolation of two known lignans, (-)-cubebin (1) and (-)-3,4-dimethoxy-3,4-desmethylenedioxycubebin (2), together with a new lignan, (-)-3-desmethoxycubebinin (3). Among these lignans, 1 and 2 showed a significant stimulatory activity of melanogenesis without any significant effects on cell proliferation.

[History and therapeutic evaluation of Citrus hassaku HORT. Tanaka].

The original plant of Citrus hassaku HORT. Tanaka was found at Jyoudo-Temple in Inno-shima, Hiroshima Prefecture, Japan by Ekei Shounin in the Edo Era. Today, the fresh raw fruits of C. hassaku are cultivated as a seasonal food, and the most famous producing district of the C. hassaku fruit is Wakayama Prefecture, representing about 60% of the Japanese output. The immature fruits of C. hassaku and its three main flavanone glycosides (naringin, neohesperidin and narirutin) have shown inhibitory activities on a compound 48/80-induced histamine release from mast cells, and anti-allergic effects on dinitrofluorobenzen (DNFB)-induced triphasic skin reaction in mice. The contents of the three flavanone glycosides in the immature fruits were higher than those in mature fruits of C. hassaku to skin care for patients with atopitic dermatitis showed improving effects in 76% of the patients. Similar efficacy was obtained for patients with pollinosis.

Promotion of hair growth by ginseng radix on cultured mouse vibrissal hair follicles.

A 70% methanol extract from red ginseng (steamed and dried roots of Panax ginseng C. A. Meyer, a kind of Ginseng Radix) had superior activity to that of white ginseng (peeled and dried root of P. ginseng, another kind of Ginseng Radix) in a hair growth promoting assay using mouse vibrissal follicles in organ culture. Of the major constituents of P. ginseng, ginsenoside-Rb(1) (G-Rb(1)) exhibited activity, but ginsenoside-Rg(1) (G-Rg(1)) and -Ro (G-Ro) were ineffective. Additionally, 20(S)-ginsenoside-Rg(3) (20(S)-G-Rg(3)) formed by the processing of red ginseng from the crude root of P. ginseng also showed hair growth promoting activity. These results indicate that Ginseng Radix possesses hair growth promoting activity, and its bioactive components are partially attributable to the ginseng saponin components mentioned above.

Antipruritic and antiinflammatory effects of aqueous extract from Si-Wu-Tang.

Si-Wu-Tang (SWT), a traditional Chinese formula, has been clinically used in the treatment of cutaneous pruritus, chronic inflammation, and other diseases. The present study was carried out to observe the antipruritic and antiinflammatory effects of SWT aqueous extract using compound 48/80 and picryl chloride (PC) models in mice. SWT (500, 1000 mg/kg p.o.) clearly reduced the scratching responses elicited by compound 48/80 in normal mice. At doses of 250 and 500 mg/kg, it inhibited the scratching responses induced by PC in mice actively sensitized with 2,4-dinitrophenol (DNP)-ovalbumin (OVA) plus alum. Furthermore, SWT (250, 500, 1000 mg/kg) significantly inhibited the footpad swelling caused by compound 48/80 in mice. In the biphasic ear skin reactions induced by PC in actively sensitized mice, SWT (250, 500 mg/kg) reduced the immediate-phase reaction, but did not affect the late-phase reaction. In vitro, SWT (50-500 microg/ml) showed a concentration-dependent inhibition of the histamine release induced by compound 48/80 from rat peritoneal mast cells. The crude drugs contained in SWT, Paeoniae Radix (25, 100 microg/ml), Rehmanniae Radix, and Chuanxiong Rhizoma (100 microg/ml), also showed a clear inhibition, but Angelica Radix did not at the concentrations examined. These findings indicate that SWT aqueous extract has antipruritic and antiinflammatory effects in mice. SWT inhibits histamine release from rat mast cells, and Paeoniae Radix probably plays a crucial role in the formula.

Anti-allergic effects of cnidii monnieri fructus (dried fruits of Cnidium monnieri) and its major component, osthol.

Anti-allergic effects (types I and IV) of the 70% ethanol extract (CM-ext) obtained from Cnidii Monnieri Fructus (dried fruits of Cnidium monnieri) were investigated on 48 h homologous passive cutaneous anaphylaxis (PCA), 2, 4-dinitrofluorobenzene (DNFB)-induced contact dermatitis and picryl chloride (PC)-induced contact dermatitis in experimental animals. CM-ext showed inhibitory effects on these allergic models. Osthol isolated from CM-ext also had the inhibitory effects. These results suggested that Cnidii Monnieri Fructus might be useful as an agent for allergic diseases and that its anti-allergic effect was partially attributable to a coumarin derivative, osthol.

Anti-androgenic and hair growth promoting activities of Lygodii spora (spore of Lygodium japonicum) I. Active constituents inhibiting testosterone 5alpha-reductase.

The aqueous ethanol extract of Lygodii Spora (spore of Lygodium japonicum (Thunb.) Sw.) showed in vitro testosterone 5alpha-reductase inhibitory activity and in vivo anti-androgenic activity using growth of flank organ in castrated Syrian hamsters and hair regrowth after shaving in testosterone-treated C57Black/6CrSlc mice. From the lipophilic constituents of Lygodii Spora, oleic, linoleic and palmitic acids were identified as the main active principles inhibiting testosterone 5alpha-reductase.

Antipruritic effect of Cnidii Monnieri Fructus (fruits of Cnidium monnieri CUSSON).

Antipruritic effects of 70% ethanol extract (CM-ext) of Cnidii Monnieri Fructus (dried fruits of Cnidium monnieri CUSSON, Umberifferae) were investigated. In mice, an oral administration of CM-ext (200 and 500 mg/kg) inhibited compound 48/80-induced scratching behavior without influence on spontaneous locomotion. Isopimpinellin (3) and osthol (1), coumarin derivatives isolated from CM-ext, showed an inhibitory effect on compound 48/80-induced scratching behavior.