Eriodictyon angustifolium extract, but not Eriodictyon californicum extract, reduces human hair greying.

OBJECTIVE: Yerba Santa (Eriodictyon angustifolium and Eriodictyon californicum) has been used for many years in traditional medicine. However, the effect of Yerba Santa on melanogenesis has not yet been investigated. We aimed to assess the biological effects of Yerba Santa on hair pigmentation. METHODS: Yerba Santa extracts were assessed for their cytological effects following X-ray irradiation treatment and then tested directly for the prevention of human hair greying. Ultra-performance liquid chromatography (UPLC) was utilized to identify the individual extract components. RESULTS: Eriodictyon angustifolium extract significantly increased melanin synthesis in the melanoma cell line through activation of the WNT/MITF/tyrosinase-signalling pathway. In contrast, E. californicum had no effect on melanin synthesis. E. angustifolium extract also demonstrated a protective effect against the damage induced by X-ray irradiation in human keratinocytes. Application of the extracts to subjects who had grey beards demonstrated a reduced number of grey beard hair per year specifically with the E. angustifolium extract. A significant decrease in grey head hair was also observed after application of E. angustifolium extract. Upregulation of gene expression related to melanin production and WNT signalling was observed after the application of E. angustifolium extract. Sterubin was the most abundant flavonoid detected by UPLC in E. angustifolium extract. In addition, sterubin showed the highest difference in terms of quantity, between E. angustifolium and E. californicum extract. CONCLUSION: Eriodictyon angustifolium extract, which is abundant in sterubin, may be suitable as a potential cosmetic and medical agent for the prevention and improvement of hair greying.

OBJECTIF: Yerba Santa (Eriodictyon angustifolium et Eriodictyon californicum) est utilisé depuis de nombreuses années en médecine traditionnelle. Cependant, l'effet de Yerba Santa sur la mélanogenèse n'a pas encore été étudié. Notre objectif était d'évaluer les effets biologiques de Yerba Santa sur la pigmentation des cheveux. MÉTHODES: Les extraits de Yerba Santa ont été évalués pour leurs effets cytologiques après un traitement d'irradiation aux rayons X, puis testés directement pour la prévention du grisonnement des cheveux humains. La chromatographie liquide ultra-performante (UPLC) a été utilisée pour identifier les composants d'extrait individuels. RÉSULTATS: L'extrait d'E. angustifolium a augmenté de manière significative la synthèse de mélanine dans la lignée cellulaire du mélanome par l'activation de la voie de signalisation WNT/MITF/tyrosinase. En revanche, E. californicum n'a eu aucun effet sur la synthèse de mélanine. L'extrait d'E. angustifolium a également démontré un effet protecteur contre les dommages induits par l'irradiation aux rayons X dans les kératinocytes humains. L'application des extraits à des sujets qui avaient une barbe grise a démontré un nombre réduit de poils gris par an spécifiquement avec l'extrait d'E. angustifolium. Une diminution significative des cheveux gris a également été observée après l'application d'extrait d'E. angustifolium. Une régulation à la hausse de l'expression des gènes liée à la production de mélanine et à la signalisation WNT a été observée après l'application d'extrait d'E. angustifolium. La stérubine était le flavonoïde le plus abondant détecté par UPLC dans l'extrait d'E. angustifolium. De plus, la stérubine a montré la plus grande différence en termes de quantité entre E. angustifolium et E. californicum. CONCLUSION: L'extrait d'E. angustifolium, qui est abondant en stérubine, peut convenir comme agent cosmétique et médical potentiel pour la prévention et l'amélioration du grisonnement des cheveux.

Environmental regulation of annual reproductive cycle in the mosquitofish, Gambusia affinis.

To clarify the environmental factors regulating the annual reproductive cycle of the female mosquitofish, Gambusia affinis, a viviparous teleost, histological changes of the ovary in natural population, and laboratory experiments were examined. The results, extending over two years, suggested that ovarian recrudescence is initiated by the rise in temperature during spring and that ovarian regression is caused by the shorter daylength during late summer. The first rearing experiments using four photoperiod-temperature groups to investigate the factors triggering the onset of reproduction revealed that females with regressing ovaries began reproduction with the rise of temperature regardless of the photoperiod during spring. The results of the second experiment using three different temperature groups indicated that vitellogenesis occurred at over 14 degrees C and pregnancy at over 18 degrees C. The third experiment with four photoperiod-temperature groups was arranged to investigate the factors in the cessation of reproduction. Sexually active females ceased vitellogenesis of the next clutch of oocytes due to the shorter daylength regardless of temperatures during late summer; however, temperature seemed to influence the rate of embryo development. The critical photoperiod is estimated at about 12.5 hr. In nature, it is supposed that vitellogenesis starts when the temperature rises to about 14 degrees C, and final maturation of oocytes occurs when the temperature reaches about 18 degrees C during spring. Then, vitellogenesis of the next clutch of oocytes ceases when the daylength becomes shorter than 12.5 hr during late summer; the last gestation proceeds at a rate dependent on the temperature, and finally reproduction ends by the last parturition. J. Exp. Zool. 286:204-211, 2000.

Enhancement of lymphatic transport of 1-(2-tetrahydrofuryl)-5-fluorouracil by polyacrylic acid aqueous gel and emulsion type suppositories in rats.

1-(2-Tetrahydrofuryl)-5-fluorouracil (FT-207) concentrations in lymph and plasma were measured after rectal administration of three types of suppositories containing FT-207. The suppositories used in this study were prepared from polyacrylic acid aqueous gel bases, emulsion type bases and a commercial fat base, witepsol w-35. Both aqueous gel and emulsion type suppositories were superior to the suppositories from witepsol with regard to FT-207 concentration in lymph and plasma. The addition of aqueous gel to the polyacrylic acid aqueous gel was found to be effective for the lymph transport from the aqueous gels. Polyacrylic acid aqueous gel containing 1% glycyrrhizin was better than other suppositories. Solidification of the emulsion type bases are also investigated, and it is suggested that these may be better substitutes of the oily suppository.

Evidence of the directive effect of 17 beta-conjugate group on the enzymatic O-methylation of catechol estrogen.

Incubations of 2-hydroxyestradiol (I), 2-hydroxyestradiol 17 beta-sulfate (II), and 2-hydroxyestradiol 17 beta-glucuronide (III) with purified rat liver catechol O-methyltransferase were carried out at pH 7.2 in the presence of Mg2+ and (3H-Me)-S-adenosyl-L-methionine. The radioactive methylated products, 2-methoxyestradiol (IV) and 2-hydroxyestradiol-3-methyl ether (V), from each substrate were quantificanted by reverse isotope dilution method after their complete separation and acetylation. In the experiments of conjugated substrates, II and III, the analyses of the methylated products were done after their hydrolysis of 17 beta-conjugate groups with acid or beta-glucuronidase. The product ratios (2-methoxy/3-methoxy) of substrates I, II, and III, were 1:1, 4:1, and 45:1, respectively. These results are suggesting that 17 beta-conjugate groups of 2-hydroxyestradiol has directive effect on enzymatic O-methylation of estrogen catechols. Further, it is estimated that following process may be present in the estradiol metabolism in rat and/or humans: estradiol leads to estradiol 17 beta-conjugates leads to 2-hydroxyestradiol 17 beta-conjugates leads to 2-methoxyestradiol 17 beta-conjugates.