Objective:To investigate the suitability of citrus-press cakes,by-products of the juice industry as a source for the whitening agents for cosmetic industry.Methods:Ethylacetate extracts of citrus-press cakes(CCE)were ...Objective:To investigate the suitability of citrus-press cakes,by-products of the juice industry as a source for the whitening agents for cosmetic industry.Methods:Ethylacetate extracts of citrus-press cakes(CCE)were examined for their anti-melanogenic potentials in terms of the inhibition of melanin production and mechanisim of melanogenesis by using Western Blot analysis with tyrosinese,tyrosinase-related protein-1(TRP-1),TRP2,and microphthalmia-associated transcription factor(MITF)proteins.To apply the topical agents,citrus-press cakes was investigated the safety in human skin cell line.Finally flavonoid analysis of CCE was also determined by HPLC analysis.Results:Results indicated that CCE were shown to down-regulate melanin content in a dose-dependent pattern.The CCE inhibited tyrosinase,TRP-2,and MITF expressions in a dose-dependent manner.To test the applicability of CCE to human skin,we used MTT assay to assess the cytotoxic effects of CCE on human keratinocyte HaCaT cells.The CCE exhibited low cytotoxicity at 50μg/mL.Characterization of the citrus-press cakes for flavonoid contents using HPLC showed varied quantity of rutin,narirutin,and hesperidin.Conclusions:Considering the anti-melanogenic activity and human safety,CCE is considered as a potential anti-melanogenic agent and may be effective for topical application for treating hyperpigmentation disorders.展开更多
During the last decade, transient receptor potential （TRP） channels emerge as key proteins in central mechanisms of the carcinogenesis such as cell proliferation, apoptosis and migration. Initial studies showed that...During the last decade, transient receptor potential （TRP） channels emerge as key proteins in central mechanisms of the carcinogenesis such as cell proliferation, apoptosis and migration. Initial studies showed that expression profile of some TRP channels, notably TRP melastatin 8 （TRPM8）, TRP vanilloid 6 （TRPV6）,TRP canonical （TRPC6） and TRPV2, is changing during the development and the progression of prostate cancer towards the hormone-refractory stages. The link between the change in expression levels and the functional role of these channels in prostate cancer is step by step being elucidated. These recent advances are here described and discussed.展开更多
Objective: To investigate the antimelanogenesis properties of three sesame compoundssesamol, sesamin and sesamolin via two stages of melanin synthesis vis-à-vis sunscreen function and enzyme inhibition in melanom...Objective: To investigate the antimelanogenesis properties of three sesame compoundssesamol, sesamin and sesamolin via two stages of melanin synthesis vis-à-vis sunscreen function and enzyme inhibition in melanoma cell line in order to search for alternative depigmenting agents.Methods: Antimelanogenic effects of sesame lignans were assessed in SK-MEL2 compared with the reference depigmenting agents, kojic acid and b-arbutin, in order to evaluate:(a) the sunscreen function of sesamol, sesamin and sesamolin by measurement of UV absorbtion property;(b) the inhibition of tyrosinase activity through mushroom and cellular tyrosinase; and(c) the effect on melanin content and melanogenic protein expression(tyrosinase, TRP-1 and TRP-2) by Western blot analysis; and(d) the toxicity of sesamol, sesamin and sesamolin to cells using cell cytotoxicity assay.Results: The results showed that sesamin, sesamolin and sesamol exerted satisfiable sunscreen function by absorbed UVB at 290 nm. Sesamol exhibited the highest inhibition of mushroom tyrosinase activity, but lipophilic sesamolin exhibited the highest cellular tyrosinase inhibition(IC_(50) of 1.6 μM) followed by sesamin, sesamol, and kojic acid,respectively. The order from high to low inhibition of melanin pigment was detected in the SK-MEL2 treated with sesamolin, sesamin, sesamol, kojic acid, and b-arbutin,respectively. Sesamolin and sesamin successfully inhibited cellular tyrosinase activity and respectively decreased TRP-1/TRP-2(36%/15%) and TRP-1 levels(16%), thereby inhibiting melanogenesis via antityrosinase activity. No cytotoxicity to SK-MEL2 or Vero(normal) cell lines was observed at the lignan concentrations that exerted an antimelanogenic effect.Conclusions: Three sesame lignans prevent melanin synthesis through 2 stages:(a) by blocking melanin-induction and(b) by interrupting melanogenic enzyme production. This study provides evidence that sesamol, sesamin and sesamolin are potential for antimelanogenesis agents.展开更多
pH plays a vital role in various cellular activities, and real-time observation of the intracellular p H through a p H indicator is very important for studying many physiological processes. In this paper, we studied t...pH plays a vital role in various cellular activities, and real-time observation of the intracellular p H through a p H indicator is very important for studying many physiological processes. In this paper, we studied the p H response of Trp–Trp dipeptide and its derivatives(NATrp_2Me, NBTrp_2 and Trp_2Me) by steady-state and time-resolved fluorescence spectroscopy. Both the fluorescence intensities and lifetimes of Trp–Trp dipeptide as well as Trp2 Me were functions of p H in the physiological range from 5.5 to 9.0. However, NATrp_2 Me and NBTrp_2 showed no difference. The exposed amino was found to be pivotal for its p H dependence. Moreover, an artificially synthesized tetrapeptide(Trp–Trp–Ala–Ser) confirmed the p H sensitivity of N-terminal Trp–Trp residues. The p H values could be quantitatively determined from the fluorescence intensities and lifetimes of the N-terminal Trp–Trp residue. Thus, the N-terminal Trp–Trp residues may be fused into the polypeptides/proteins to serve as an intrinsic p H indicator in fluorescence spectroscopy and imaging.展开更多
基金Supported by the Next-Generation BioGreen 21 Program,Rural Development Administration,Republic of Korea,Grant No.PJ009583002013
文摘Objective:To investigate the suitability of citrus-press cakes,by-products of the juice industry as a source for the whitening agents for cosmetic industry.Methods:Ethylacetate extracts of citrus-press cakes(CCE)were examined for their anti-melanogenic potentials in terms of the inhibition of melanin production and mechanisim of melanogenesis by using Western Blot analysis with tyrosinese,tyrosinase-related protein-1(TRP-1),TRP2,and microphthalmia-associated transcription factor(MITF)proteins.To apply the topical agents,citrus-press cakes was investigated the safety in human skin cell line.Finally flavonoid analysis of CCE was also determined by HPLC analysis.Results:Results indicated that CCE were shown to down-regulate melanin content in a dose-dependent pattern.The CCE inhibited tyrosinase,TRP-2,and MITF expressions in a dose-dependent manner.To test the applicability of CCE to human skin,we used MTT assay to assess the cytotoxic effects of CCE on human keratinocyte HaCaT cells.The CCE exhibited low cytotoxicity at 50μg/mL.Characterization of the citrus-press cakes for flavonoid contents using HPLC showed varied quantity of rutin,narirutin,and hesperidin.Conclusions:Considering the anti-melanogenic activity and human safety,CCE is considered as a potential anti-melanogenic agent and may be effective for topical application for treating hyperpigmentation disorders.
文摘During the last decade, transient receptor potential （TRP） channels emerge as key proteins in central mechanisms of the carcinogenesis such as cell proliferation, apoptosis and migration. Initial studies showed that expression profile of some TRP channels, notably TRP melastatin 8 （TRPM8）, TRP vanilloid 6 （TRPV6）,TRP canonical （TRPC6） and TRPV2, is changing during the development and the progression of prostate cancer towards the hormone-refractory stages. The link between the change in expression levels and the functional role of these channels in prostate cancer is step by step being elucidated. These recent advances are here described and discussed.
基金2011 (#542800) and 2012 (#552900), Khon Kaen University Research Funding supported this project
文摘Objective: To investigate the antimelanogenesis properties of three sesame compoundssesamol, sesamin and sesamolin via two stages of melanin synthesis vis-à-vis sunscreen function and enzyme inhibition in melanoma cell line in order to search for alternative depigmenting agents.Methods: Antimelanogenic effects of sesame lignans were assessed in SK-MEL2 compared with the reference depigmenting agents, kojic acid and b-arbutin, in order to evaluate:(a) the sunscreen function of sesamol, sesamin and sesamolin by measurement of UV absorbtion property;(b) the inhibition of tyrosinase activity through mushroom and cellular tyrosinase; and(c) the effect on melanin content and melanogenic protein expression(tyrosinase, TRP-1 and TRP-2) by Western blot analysis; and(d) the toxicity of sesamol, sesamin and sesamolin to cells using cell cytotoxicity assay.Results: The results showed that sesamin, sesamolin and sesamol exerted satisfiable sunscreen function by absorbed UVB at 290 nm. Sesamol exhibited the highest inhibition of mushroom tyrosinase activity, but lipophilic sesamolin exhibited the highest cellular tyrosinase inhibition(IC_(50) of 1.6 μM) followed by sesamin, sesamol, and kojic acid,respectively. The order from high to low inhibition of melanin pigment was detected in the SK-MEL2 treated with sesamolin, sesamin, sesamol, kojic acid, and b-arbutin,respectively. Sesamolin and sesamin successfully inhibited cellular tyrosinase activity and respectively decreased TRP-1/TRP-2(36%/15%) and TRP-1 levels(16%), thereby inhibiting melanogenesis via antityrosinase activity. No cytotoxicity to SK-MEL2 or Vero(normal) cell lines was observed at the lignan concentrations that exerted an antimelanogenic effect.Conclusions: Three sesame lignans prevent melanin synthesis through 2 stages:(a) by blocking melanin-induction and(b) by interrupting melanogenic enzyme production. This study provides evidence that sesamol, sesamin and sesamolin are potential for antimelanogenesis agents.
基金supported by the National Natural Science Foundation of China(6110807761178085)+2 种基金the Science and Technology Commission of Shanghai Municipality(1552071150015ZR1411700)the Program of Introducing Talents of Discipline to Universities(B12024)
文摘pH plays a vital role in various cellular activities, and real-time observation of the intracellular p H through a p H indicator is very important for studying many physiological processes. In this paper, we studied the p H response of Trp–Trp dipeptide and its derivatives(NATrp_2Me, NBTrp_2 and Trp_2Me) by steady-state and time-resolved fluorescence spectroscopy. Both the fluorescence intensities and lifetimes of Trp–Trp dipeptide as well as Trp2 Me were functions of p H in the physiological range from 5.5 to 9.0. However, NATrp_2 Me and NBTrp_2 showed no difference. The exposed amino was found to be pivotal for its p H dependence. Moreover, an artificially synthesized tetrapeptide(Trp–Trp–Ala–Ser) confirmed the p H sensitivity of N-terminal Trp–Trp residues. The p H values could be quantitatively determined from the fluorescence intensities and lifetimes of the N-terminal Trp–Trp residue. Thus, the N-terminal Trp–Trp residues may be fused into the polypeptides/proteins to serve as an intrinsic p H indicator in fluorescence spectroscopy and imaging.
