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Objective To evaluate the effect of latanoprost on cell proliferation of and melanogenesis in human epidermal melanocytes,and to explore its mechanism.Methods Latanoprost was added into the 254 medium to prepare latanoprost solutions at different concentrations of 10-5,10-6 and 10-7 mol/L.In vitro cultured human epidermal melanocytes were divided into 4 groups to be cultured with media containing no latanoprost (control group) or 10-5,10-6 and 10-7 mol/L latanoprost for 48 hours.Cell counting kit-8 (CCK8) assay was performed to evaluate the proliferative activity of melanocytes,dopa oxidation assay to estimate the activity of tyrosinase.Sodium hydroxide (NaOH)-lysis method was used to determine the content of melanin,and Masson-Fontana staining to observe the number and distribution of melanin granules.Westernblot analysis and real-time fluorescence-based quantitative PCR were performed to determine the protein and mRNA expression of melanogenesis-related genes including microphthalmia-associated transcription factor (MITF),tyrosinase (TYR) and tyrosinase-related protein 1 (TYRP1).Comparison among the 4 groups and multiple comparisons were done by using one-way analysis of variance and least significant difference (LSD)-t test.Results Compared with the control group,the 10-6-,10-5-mol/L latanoprost groups showed significantly increased proliferative activity of melanocytes (1.064 ± 0.172 and 1.078 ± 0.080 vs.0.784 ± 0.015;t =3.289,3.454 respectively,both P ＜ 0.05),increased activity of tyrosinase (0.510 ± 0.017 and 0.454 ± 0.009 vs.0.355 ± 0.041;t =6.139,3.939 respectively,P ＜ 0.01 or 0.05),and increased content of melanin (t =7.232,5.967,both P ＜ 0.01).However,there were no significant differences in the proliferative activity of melanocytes,activity of tyrosinase or content of melanin between the 10-7-mol/L latanoprost group and control group (all P ＞ 0.05).Masson-Fontana staining showed more and darker melanin granules on melanocyte dendrites in the 10-5-,10-6-,10-7-mol/L latanoprost groups than in the control group,and the color of melanin granules changed from light brown to black brown along with the increase in the concentration of latanoprost.The mRNA expression of MITF increased along with the increase in the concentration of latanoprost (P ＜ 0.01),and the protein expression of MITF wassignificantly higher in the 10-6,10-5-mol/L latanoprost groups than in the control group and 10-7-mol/L latanoprost group (all P ＜ 0.01).The 10-6-mol/L latanoprost group showed significantly increased mRNA and protein expression of TYR and TYRP1 compared with the control group,10-7-,10-5-mol/L latanoprost groups (all P ＜ 0.01).Conclusion Latanoprost can increase the proliferation of human epidermal melanocytes,and promote tyrosinase activity and melanogenesis likely by enhancing the mRNA and protein expression of MITF,TYR,TYRP1.
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Objective To study the effect of Corylin on A375 cells melanin synthesis,and explore its mechanism.Methods The cells were randomly divided into the control group, the estradiol group, and corylin group including 10-3μmol/L, 10-2μmol/L, 10-1μmol/L, 1μmol/L, 10μmol/L, 100μmol/L. Estradiol estradiol intervention group were given 10-3 mol/L. Corylin group (10-3μmol/L, 10-2μmol/L, 10-1μmol/L, 1μmol/L, 10μmol/L,100μmol/L) were given 10-3μmol/L, 10-2μmol/L, 10-1μmol/L, 1μmol/L, 10μmol/L, 100μmol/L corylin intervention. The activity of proliferation were detected by MTT, NaOH method, dopa oxidation , both melanin content and tyrosinase activity (tyrosinase, TYR). TYR, yrosinase related protein (tyrosinase related protein, TRP)-1 and TRP-2 expression levels of mRNA were determined by RT-PCR.Results Compared with the control group, 10, 100μmol/L of Corylin group cell proliferation rate significantly decreased (P<0.01). The 1μmol/L, 10-1μmol/L, 10-2μmol/L of Corylin group cell melanin content, TYR significantly decreased (P<0.01 or P<0.05). The 1μmol/L corylin group TYR (0.303 ± 0.003vs. 0.628 ± 0.012), TRP-1 (0.313 ± 0.008 vs. 0.677 ± 0.022), TRP-2 (0.456 ± 0.028vs. 0.687 ± 0.020) mRNA expression level significantly decrease (P<0.01).Conclusions The results showed that Corylin could inhibit melanin synthesis, which worked probably through inhibiting the activity of TYR and cutting the mRNA expressions of TYR,TRP-1/2.
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Objective To investigate relationships between serum levels of anti?tyrosinase IgG antibody(TYR IgG)as well as anti?tyrosinase?related protein?1 IgG antibody(TRP?1 IgG)and vitiligo. Methods Enzyme linked immunosorbent assay(ELISA)was performed to detect serum levels of TYR IgG and TRP?1 IgG in 260 patients with vitiligo and 50 health controls. The threshold for defining a positive test result was set at 3 standard deviations above the mean serum level of TYR IgG or TRP?1 IgG in the healthy controls. Results The positive rate of TYR IgG and/or TRP?1 IgG in the vitiligo group was 57.31%(149/260). The positive rates of TYR IgG and TRP?1 IgG were both significantly higher in the vitiligo group than in the control group(TYR IgG:37.3%[97/260]vs. 0,χ2=25.441, P0.05). Among patients with vitiligo, the positive rate of TRP?1 IgG was significantly higher in females than in males(χ2=5.811, P20 years(χ2=6.498, P 20 years (both P >0.05). Conclusion Detection of TYR IgG and TRP?1 IgG may provide some evidence for the diagnosis and treatment of vitiligo.
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Objective To evaluate the effect of puerarin on melanogenesis in melanocytes,and to explore its possible mechanisms.Methods Third-to fifth-passage melanocytes isolated from human foreskin were treated with different concentrations (1,5,10,20,40,80 and 160 μmol/L) of puerarin for 24 hours,with those receiving no treatment as the normal control group.Methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate the proliferative activity of melanocytes,a sodium hydroxide solubilization method was used to measure melanin content,and reverse transcription PCR (RT-PCR) and Western blot analysis were performed to quantify the mRNA and protein expressions of microphthalmia-associated transcription factor (MITF),tyrosinase (TYR) and tyrosinase-related protein-1 (TRP-1) respectively.Results There were no significant differences in the proliferative activity of melanocytes between the puerarin (1-40 μmol/L) groups and normal control group (P ＞ 0.05),and 40 μmol/L was chosen as the concentration of puerarin for subsequent experiments.Compared with the normal control group,the 40-μmol/L puerarin group showed increased melanin content as well as mRNA and protein expressions of MITF,TYR and TRP-1 (all P ＜ 0.05).Concretely speaking,the protein expressions of MITF,TYR and TRP-1 in the 40-μmol/L puerarin group were increased by 8.69％,10.28％ and 10.58％ compared with the normal control group respectively (all P ＜ 0.05),and their mRNA expressions were 2.48,1.91 and 1.63 times higher in the 40-μmol/L puerarin group than in the normal control group respectively (all P ＜ 0.05).Conclusion Puerarin can increase the mRNA and protein expressions of MITF,TYR and TRP-1,and promote melanogenesis in melanocytes.
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Objective To investigate the effect of ellagic acid on human epidermal melanocyte melanogenesis and melanin transfer, and the mechanism thereof. Methods The human melanocytes and and keratinocytes were co-cultured and purified. After passing the second generation, cells of 1∶10 ratio were inoculated into the small dish (3 cm × 3 cm). The changes of melanin content and tyrosinase activity in melanocytes were detected before and after intervention with ellagic acid (100, 10 and 1 mg/L) for 48 h. The melanin transfer in cultured cells was detected by flow cytometry method. The 10 nmol/L arbutin was used as the positive control. Results The tyrosinase activity was down-regulated by ellagic acid in a dose-dependent manner. The ellagic acid can reduce the melanin content except for the 1 mg/L of ellagic acid. The melanin transfer was also inhibited by ellagic acid in a dose-dependence manner. Conclusion Ellagic acid can be used for skin-whitening cosmetic and the depigmenting effect might be due to the down-regulation of melanogenesis and melanin transfer.
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Objective To investigate the effect of nuclear translocation of E2p45 related factor 2 (Nrf2)on the biological activity of melanocytes.Methods Plasmid vectors containing wild-type nrf2 gene (pcDNA-nrf2) and nls-deleted nrf2 gene (pcDNA-nrf2△nls) were constructed.B10BR normal murine melanocytes were classified into three groups,i.e.,untransfected group,wild-type nrf2 group transfected with pcDNA-nrf2,and mutated nrf2 group transfected with pcDNA-nrf2△nls.Each of the above groups were further divided into three subgroups:control subgroup receiving no treatment,hydrogen peroxide (H2O2) subgroup treated with H2O2 of 200 μmol/L for 24 hours,and combined subgroup pretreated with tert-butyl hydroquinone (TBHQ) followed by treatment with H2O2 of 200 μmol/L for 24 hours.Subsequently,methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate the proliferative activity of cells,dopa oxidation assay to determine tyrosinase activity,Transwell assay to estimate cell migration ability,Western blot to quantify the expressions of Nrf2 and his tag fusion protein.Results TBHQ significantly enhanced the nuclear expression of Nrf2 in B10BR cells transfected with pcDNA-nrf2 or pcDNA-nrf2△nls (both P ＜ 0.01).No significant difference was observed in tyrosinase activity between untreated wild-type nrf2 group,mutated nrf2 group,and untransfected group (P ＞ 0.05).There was a statistical decrease in tyrosinase activity in the two H2O2-treated transfected groups compared with the untreated transfected groups (both P ＜ 0.05),and the decrease was reversed by TBHQ pretreatment in the wildtype nrf2 group (P ＜ 0.05),but not in the mutated nrf2 group (P ＞ 0.05).Further more,the proliferative activity of B10BR cells experienced no obvious changes in the wild-type nrf2 group (P ＞ 0.05),but was significantly reduced in the untransfected group (P ＜ 0.05) and mutated nrf2 group (P ＜ 0.01) after the H2O2 treatment compared with the corresponding untreated groups.TBHQ could protect the pcDNA-nrf2-transfected B10BR cells,but not pcDNA-nrf2△nls-transfected B10BR cells,from H2O2-induced oxidative damage.Transwell assay showed no significant difference in migration ability among these nine groups (P ＞ 0.05).Conclusions Abnormal nuclear translocation of Nrf2 could affect antioxidant activity of,proliferative activity of and tyrosinase activity in melanocytes.TBHQ may enhance the tyrosinase activity in,proliferative activity and antioxidant activity of melanocytes via activating the nuclear expression of wild type Nrf2.
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Objective To study the impact of sodium arsenite(NaAsO2) exposure on melanoma cells A375 (hereinafter referred to as the A375) and G361 (hereinafter referred to as the G361) pigment production and tyrosinase (TYR) activity and the differences of pigment metabolism capacity between the cell lines.Methods A375 and G361 cells were exposed to sodium arsenite at concentrations of 0.0(control),0.1 and 1.0 μmol/L for 72hours.Cell viability was measured by Alamar Blue assay.Melanin levels and TYR activity were measured at the same time.Results After exposure for 72 hours,the cells of 0.1 μmol/L dose groups of both of the two cell lines [A375:(103.32 + 1.26)％; G361:(104.10 + 1.76)％] showed a slightincrease of proliferation without significant differences compared with those of the control[A375:(100.00 ± 1.08)％; G361:(100.00 + 1.79)％,all P ＜ 0.05] ;while cell viability of the 1.0 μmol/L dose group of both of the two cell lines[A375:(75.32 ± 1.59)％; G361:(78.26 ± 2.10)％] were significantly lower than those of the control (all P ＜ 0.05).Melanin levels of G361 cell line [(7.19 ± 0.35),(7.34 ± 0.83),(8.19 ± 0.86)pg/cell] were significantly higher than that of A375[(4.35 ± 0.72),(4.54 ± 0.01),(4.60 + 0.59)pg/cell,all P ＜ 0.05] in all the three groups.TYR activity of G361 cell line [(54.13 ± 1.21),(54.56 ± 0.21),(56.25 ± 0.85)Bq] were also markedly higher than that of A375 cell[(42.00 ±0.21),(42.90 ± 0.54),(42.91 ± 0.01)Bq,all P ＜ 0.05] in all the three groups.The melanin levels and TYR activities of both of the two cells lines showed an increase tendency along with increased doses of arsenic exposure,but without significant differences when compared with those of the three groups (all P ＞ 0.05).Conclusions Arsenic related pigment disorder may be associated with increased melanin levels and TYR activities induced by arsenic exposure; individual difference of pigment metabolism may be associated with different basal melanin levels and TYR activity between different individuals.
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[Objective] To estimate the effects of ginsenoside Rb1 on melanogenesis in human melanocytes and underlying mechanisms.[Methods] Epidermal melanocytes were obtained from circumcision specimens of children,and subjected to primary culture.After 2 to 5 passages,the melanocytes were treated with different concentrations of ginsenoside Rb1,dimethyl sulfoxide (DMSO,vehicle control),forskolin at 10 μmol/L(positive control) or remained untreated (blank control).After additional culture for 72 hours,methyl thiazolyl tetrazolium (MTT) assay and NaOH lysis method were used to evaluate cell viability and melanin content in melanocytes respectively,spectrophotometer to determine dopa oxidase activity of tyrosinase,Western blot to quantify the protein level of tyrosinase,microphthalmia-associated transcription factor (MITF),phosphorylated and total cAMP response element binding protein (p-CREB and t-CREB) in melanocytes.[Results] After treatment with ginsenoside Rbl of 25,50 and 100 μmol/L for 72 hours,the melanocytes experienced no significant changes in viability (P ＞ 0.05 ),but a significant dose-dependent increase in melanin content (112.4％± 5.7％,155.7％ + 6.3％,217.2％ ± 11.7％ vs.100％,P＜ 0.05 or 0.01) and tyrosinase activity(117.9％ ± 5.7％,158.2％ ± 9.6％,182.6％ ± 10.0％ vs.100％,P＜ 0.05 or 0.01 ) compared with the vehicle control melanocytes.The protein expressions of tyrosinase,MITF and p-CREB were statistically higher in melanocytes treated with ginsenoside Rb1 of 100 μmol/L for 72 hours than in the vehicle control melanocytes (225.4％ ± 12.8％ vs.100％ ± 7.9％,313.5％ ± 16.7％ vs.100％ ± 9.8％,322.5％ ± 21.1％ vs.100％ ± 9.1％,all P＜ 0.01).The increase in MITF protein expression was inapparent in melanocytes at 8 hours after the treatment with ginsenoside Rb1 of 100 μmol/L,but statistically significant at 24 hours compared with the melanocytes at baseline (P＜ 0.01).The pretreatment with H-89 (a 8elective inhibitor of PKA) at 10 μmol/L,significantly suppressed the ginsenoside Rb1 (100 μmol/L for 72 hours) -induced phosphorylation of CREB,increase in MITF,tyrosinase expression,as well as tyrosinase activity and melanin content in melanocytes (all P ＜ 0.01 ).[Conclusion]s Ginsenoside Rb1could enhance the melanogenesis and tyrosinase activity in normal human melanocytes.The PKA/CREB/MITF/ tyrosinase signaling pathway may contribute to the pro-melanogenic effect of ginsenoside Rb1.
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ObjectiveTo evaluate the effects of all-trans retinoic acid(ATRA) on melanin content,activity and protein expression of tyrosinase,mRNA expression of Cu/Zn superoxide dismutase(SOD) in A375 cells irradiated with ultraviolet B(UVB).MethodsCultured A375 cells were classified into 6 groups:ATRA+UVB group treated with ATRA after UVB irradiation,hydroquinone+UVB group treated with hydroquinone after UVB irradiation,UVB group and ATRA group treated with UVB irradiation and ATRA respectively,negative control group receiving no treatment.Melanin content and tyrosinase activity were determined by NaOH solubilization assay and dopa-oxidation assay respectively at 24,48 and 72 hours after the addition of ATRA into medium.Western blot was performed to detect the protein expression of tyrosinase,and real-time quantitative PCR to measure the mRNA expressions of tyrosinase and Cu/Zn SOD in A375 cells after 24-hour culture with ATRA.ResultsThe melanin content and tyrosinase activity decreased in UVB-irradiated cells after being treated with ATRA for 24,48 and 72 hours.The protein (gray scale) and mRNA (2-△△Ct value) expression levels of tyrosinase were 0.72 ± 0.070 and 1.400 ± 0.135 respectively at 24 hours after UVB irradiation,decreased to 0.42 ± 0.056(P ＜0.01) and 0.810 ± 0.062(P ＜ 0.01 ) respectively after additional treatment with ATRA.The mRNA expression level of Cu/Zn SOD was 0.323 ± 0.066 in A375 cells at 24 hours after UVB irradiation,and increased to 0.625 ±0.103 (P ＜ 0.01 ) after additional treatment with ATRA.ConclusionATRA can suppress UVB-induced increase in melanin synthesis and elevate Cu/Zn SOD level in A375 cells,likely through tyrosinase pathway.
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Objective To investigate the effect of heat treatment on the proliferation of, melanin synthesis and tyrosinase activity in cultured normal human melanocytes. Methods Normal human foreskin tissue was obtained by sterile circumcision and melanocytes were harvested by using methods for epidermal cell culture. Basic fibroblast growth factor (bFGF) was utilized as the primary mitogen to establish the culture system of normal human epidermal melanocytes. Masson-Fontana staining was proformed to identify melanocytes.Third-passage melanocytes were treated with hyperthermia at various temperatures (39 ℃, 41 ℃, 42 ℃, 43 ℃ and 45℃) for 1 hour a day for consecutive 3 days followed by the measurement of cell viability with MTT assay. The hyperthermia at optimized temperature was used to treat fourth-passage melanocytes for 1 hour a day for consecutive 3 days; subsequently, the tyrosinase activity were detected with L-Dopa as the substrate, and melanin content was determined in heat-treated and untreated (control) melanocytes. Results The hyperthermia at 42 ℃ exhibited the strongest promotive effect on the proliferation of melanocytes among these 5 hyperthermia conditions. After treatment with hyperthermia at 42 ℃ for 1 hour a day for consecutive 3 days, melanocytes showed an increment in tyrosinase activity by 36.4% and melanin synthesis by 78% compared with the untreated melanocytes (both P＜0.05). Conclusions Heat treatment can enhance the proliferation of cultured human melanocytes, promote their melanin synthesis and tyrosinase activity.
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Objective To evaluate the biological effect of endothelin (ET) antagonist on cultured B16 murine melanoma cells. Methods B16 murine melanoma cells were cultured in the presence of various concentrations (31.25, 62.5, 125, 250, 500 μg/mL) of ET antagonist or licoflavone. Then, melanoma cells were harvested for the detection of tyrosinase activity and melanin content. The proliferation rate of melanoma cells was measured with MTT method. The effect of ET antagonist was compared with that of licoflavone. Results Licoflavone had a concentration-dependent inhibition on melanogenesis. The ET antagonist selectively suppressed the ET-induced stimulation of tyrosinase and cell differentiation of B16 cells, but had no direct inhibitory effect on melanogenesis in culture, and little influence on melanocyte viability. The addition of ET antagonist at 200 μg/mL could significantly inhibit ET (0.5 μg/mL)-induced melanogenesis in Bl6 cells. The cytotoxity of the antagonist was relatively lower than that of licoflavone. Conclusions The results suggest that the ET antagonist is a safe skin-whitening ingredient, and may have a wide application perspective in the prevention of endothelin-induced skin pigmentation after UVB irradiation.
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ibits tyrosinase activity and melanogenesis in murine B16 melanoma cells. Hence, N-acetylglucosamine may serve as a skin lightening agent in the future.
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Objective To investigate the effect of calcipotriol on melanin synthesis by human melanocytes and its possible action mechanism.Methods Primary melanocytes were cultured with various concentrations(10~(-5),10~(-6),10~(-7),10~(-8),10~(-9),10~(-10) mol/L)of calcipotriol for 24 or 48 hours.Subsequently,MTT assay,NaoH assay.Dopa-oxidase assay,Western blot and semiquantitative RT-PCR were used to measure the cell proliferation of,melanin synthesis by.tyrosinase activity,protein and mRNA expression levels in the melanocytes.respectively.Those untreated melanocytes served as the control.Results The calcipotriol between 10~(-9) and 10~(-5) mol/L had no significant effect on the proliferation of cultured melanocytes(P＞0.05).while that of 10~(-9) and 10~(-8) mol/L increased tyrosinase activity by 137%and 123%,and enhanced melanin synthesis by 40.63%and 18.75%,respectively,compamd with untreated melanocytes(both P＜0.05).Moreover,the tyrosinase protein level increased by 270.4%(P＜0.05)in melanocytes treated with calcipotriol at 10~(-9) mol/L for 24 hours.The strongest tyrosinase activity and melanin synthesis was observed in melanocytes treated with calcipotriol of 10~(-9) moI/L.Conclusions The proliferation of melanocytes is unaffected by calcipotriol at 10~(-9) to 10~(-5) mol/L,but it can elevate the expression of tyrosinase protein,enhance tyrosinase activity,and promote melanin synthesis in melanocytes.
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In this study, the essential oil from lotus flower extract, including petals and stamens, was assessed with regard to its effects on melanogenesis in human melanocytes. The lotus flower essential oil was shown to stimulate melanin synthesis and tyrosinase activity in a dose-dependent manner. The lotus flower essential oil induced the expression of tyrosinase, microphthalmia-associated transcription factor M (MITF-M), and tyrosinase-related proten-2 (TRP-2) proteins, but not tyrosinase mRNA. Moreover, it increased the phosphorylation of ERK and cAMP response element binding protein (CREB). In order to verify the effective components of the lotus flower oil, its lipid composition was assessed. It was found to be comprised of palmitic acid methyl ester (22.66%), linoleic acid methyl ester (11.16%), palmitoleic acid methyl ester (7.55%) and linolenic acid methyl ester (5.16%). Among these components, palmitic acid methyl ester clearly induced melanogenesis as the result of increased tyrosinase expression, thereby indicating that it may play a role in the regulation of melanin content. Thus, our results indicate that lotus flower oil may prove useful in the development of gray hair prevention agents or tanning reagents.
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Humans , Blotting, Western , Cell Proliferation , Cyclic AMP/metabolism , Cyclic AMP Response Element-Binding Protein/genetics , Flowers/chemistry , Gas Chromatography-Mass Spectrometry , Intramolecular Oxidoreductases/genetics , Lotus/chemistry , Melanins/biosynthesis , Melanocytes/drug effects , Microphthalmia-Associated Transcription Factor/genetics , Monophenol Monooxygenase/genetics , Phosphorylation , Plant Oils/pharmacology , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Skin/cytologyABSTRACT
Xanthohumol (XH), the principal prenylflavonoid of the hop plant (Humulus lupulus L.), dose-dependently inhibited isobutylmethylxanthine (IBMX)-induced melanogenesis in B16 melanoma cells, with little cytotoxicity at the effective concentrations. Decreased melanin content was accompanied by reduced tyrosinase enzyme activity, protein and mRNA expression. The levels of tyrosinase-related protein 1 and 2 mRNAs were decreased by XH. XH also inhibited alpha-melanocyte stimulating hormone- or forskolin-induced increases in melanogenesis, suggesting an action on the cAMP-dependent melanogenic pathway. XH downregulated the protein and mRNA expression of microphthalmia-associated transcription factor (MITF), a master transcriptional regulator of key melanogenic enzymes. These results suggest that XH might act as a hypo-pigmenting agent through the downregulation of MITF in the cAMP-dependent melanogenic pathway.
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Animals , Mice , 1-Methyl-3-isobutylxanthine/pharmacology , Cell Line , Cell Survival/drug effects , Dose-Response Relationship, Drug , Down-Regulation , Drug Antagonism , Colforsin/pharmacology , Humulus , Intramolecular Oxidoreductases/antagonists & inhibitors , Melanins/antagonists & inhibitors , Melanocytes/drug effects , Melanoma, Experimental , Membrane Glycoproteins/antagonists & inhibitors , Microphthalmia-Associated Transcription Factor/antagonists & inhibitors , Monophenol Monooxygenase/antagonists & inhibitors , Oxidoreductases/antagonists & inhibitors , Propiophenones/pharmacology , Signal Transduction/drug effects , alpha-MSH/metabolismABSTRACT
OBJETIVO: Avaliar a possibilidade de identificação de células malignas circulantes nas amostras de sangue periférico de pacientes brasileiros com melanoma maligno de coróide enviadas para análise no exterior. MÉTODOS: Os marcadores melan-A e tirosinase foram usados para detectar a presença de células malignas circulantes, pela transcrição reversa seguida de reação em cadeia da polimerase e análise seqüencial de DNA (RT-nested-PCR), em seis pacientes com melanoma maligno de coróide, diagnosticados no Brasil. RESULTADOS: Cinco pacientes deste grupo (83,33 por cento) foram considerados positivos. A reação de RT-nested-PCR foi positiva para melan-A em quatro (66,7 por cento) e positiva para tirosinase em quatro (66,7 por cento) dos seis pacientes testados. Três (50 por cento) pacientes foram positivos para os dois marcadores. Um (16,7 por cento) paciente foi negativo para ambos marcadores. CONCLUSÃO: A pesquisa de células malignas circulantes usando RT-nested-PCR, foi positiva na maioria dos pacientes estudados. A qualidade das amostras de sangue periférico dos pacientes brasileiros foi mantida no material preservado mesmo após ter sido enviado ao exterior.
PURPOSE: The purpose of our study was to detect circulating malignant cells (CMCs) in oversea-shipped blood samples of patients with uveal melanoma diagnosed in Brazil. METHODOS: Melan-A and tyrosinase were the two markers used for the detection of CMCs, using reverse transcriptase nested polymerase chain reaction (RT-nested-PCR) in 6 patients with uveal melanoma. The expression of beta-actin and GAPDH were used to assess the quality of the material. RESULTS: Five patients (83.33 percent) tested positive for the presence of CMCs. The RT-nested-PCR was positive for melan-A in 4 patients (66.7 percent) and positive for tyrosinase in 4 (66.7 percent) of the 6 patients. Three (50 percent) patients were positive for both markers. One (16.7 percent) patient was negative for both markers. All negative controls were negative. CONCLUSION: The quality of the blood samples shipped overseas, from patients with uveal melanoma, was preserved. The detection of CMCs using RT-nested-PCR was positive in the majority of the patients.
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Adult , Aged , Female , Humans , Male , Middle Aged , Antigens, Neoplasm/blood , Melanoma/secondary , Monophenol Monooxygenase/blood , Neoplastic Cells, Circulating/chemistry , Neoplasm Proteins/blood , Biomarkers, Tumor/blood , Uveal Neoplasms/pathology , Follow-Up Studies , Melanoma/blood , Specimen Handling , Time Factors , Uveal Neoplasms/bloodABSTRACT
0.05). However, this medicine significan tly enhanced c-kit expression in melanocytes in vitro with an increase of 79.41% . Conclusions The efficacy of supplemented four agents decoction formula in th e treatment of vitiligo may be related to the SCF (stem cell factor)/c-kit pathw ay. This Chinese traditional medicine may enhance c-kit expression, but may not be associated with cell proliferation and Tyr expression of melanocytes.
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Objective To study the effects of several Chinese traditional medicines (CTM) on cell proliferation, cell toxicity, gene expression of Tyr and c-kit in normal melanocytes cultured from Caucasians. Methods The TRP and KIT protein expression was detected by Western blotting. The total soluble protein of melanocytes was measured by spectrophotometer by its absorption at 595nm against the standard concertration curre. Results Angelica dahurica, Fructus psoraleae, Spica Prunellae, Ligusticum chuanxiong Hort, and Eclipta Prostrasta stimulated the expression of KIT and the synthesis of total protein. The stimulating effect of Angelica dahurica and and Fructus psoraleae on the KIT expression was 69.44% and 58.43% respectively. However, these medicines only had a limited effect on the expression of Tyr in melanocytes. Conclusions The therapeutic effect of CTM on vitiligo may be related with the SCF/KIT pathway. This study might provide an useful way to screen more Chinese medicine for the treatment of vitiligo.
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Objective To study the effects of glabridin on human melanocytes and B16 murine melanoma cells. Methods After glabridin was added into the two kinds of cultured melanocytes, the cell viability, tyrosinase activity and melanin contents were measured, respectively. The effects of glabridin were compared with those of hydroquinone. Results It was shown that the effects of glabridin and hydroquinone on two kinds of cells were different. Compared with hydroquinone, glabridin had a concentration-dependent inhibition on melanogenesis and little influence on melanocyte viability. Conclusion There is a biological diversity between human melanocytes and murine melanoma cells. It is indicated that glabridin is a safe and active ingredient for depigmentation.
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AIM: To inhibit the expression of tyrosinase gene in murine B16 melanoma cells by antisense nucleotide. METHODS: The antisense recombinant pcDNA3.1(-)-tyr was constructed and was used to infect murine B16 melanoma cells for expression of tyr antisense nucleotide. The effect of antisense nucleotide of tyr on the expression of tyr gene was detected by determination of the activity of tyrosinase and of the production of melanin, Dopa staining and electronic microscope. RESULTS: The tyr antisense recombinant was successfully constructed and injected into murine B16 melanoma cell. The activity of tyrosinase in B16 cells infected with pcDNA3.1 (-)-tyr decreased to 0.0498?0.0036, compared to the tyrosinase activity of 0.0916?0.0132 in the control cells without treatment (P