The enzymatic oxidation of (+)-catechin (Cat) with copper-containing oxidase, tyrosinase, was applied to hair colouring in the study. The Cat is oxidised to be o-benzoquinone form, the catechinone, which works as the ...The enzymatic oxidation of (+)-catechin (Cat) with copper-containing oxidase, tyrosinase, was applied to hair colouring in the study. The Cat is oxidised to be o-benzoquinone form, the catechinone, which works as the hair dyestuff. Four kinds of hair colouring techniques using Cat were examined and each of their dyeability was compared in order to improve it. The first dyeing method is dyeing hair by the redissolved catechinone, which is preliminarily obtained by the oxidation of Cat (Redissolution Dyeing Method). The second one is dyeing hair in the dye solution just after the dye being formed by the enzymatic reaction (Sequential Dyeing Method). The third one is dyeing hair in solution containing Cat and the dyeing process is accompanied by the oxidation of Cat (Simultaneous Oxidation Dyeing Method). The fourth one is two-step dyeing that the hair immersed in Cat solution at the first step and then it is oxidised enzymatically to colour at the second step (Post-Oxidation Dyeing Method). The hair is dyed pale yellow by Redissolution Method, deeper yellowish brown by Sequential and Simultaneous Oxidation Dyeing Method and slightly reddish brown by Post-Oxidation Method with Cat. The order of their dyeability is the Simultaneous Oxidation ≈ Post-Oxidation > Sequential > Redissolution Dyeing Method at 30°C. The dyeability of Redissolution Method increases with an increase in dyeing temperature (T) between 20°C - 60°C. In Simultaneous Oxidation Method, the T increment also provides higher dyeability, and the colour of dyed hair becomes duller over 50°C. The Post-Oxidation Method shows higher dyeability at the lower oxidation temperature (20 °C - 40°C).展开更多
In the study, hair colouring by utilising enzymatic oxidation of nine species of bio-catechols, which are biobased materials having the catechol (o-dihydroxybenzene) group, was examined. The bio-catechols used are (+)...In the study, hair colouring by utilising enzymatic oxidation of nine species of bio-catechols, which are biobased materials having the catechol (o-dihydroxybenzene) group, was examined. The bio-catechols used are (+)-catechin (Cat), (-)-epicatechin (EC), L-3,4-dihydroxyphenylalanine (DOPA), hematoxylin (HX), brazilin (BZ), rosmarinic acid (RA), caffeic acid (CA), chlorogenic acid (ChA) or ellagic acid (EA). The dyeability of human white hair samples dyed by two kinds of dyeing methods using the bio-catechols was compared. First one is dyeing hair during the enzymatic oxidation of a bio-catechol dye precursor in a dye solution (simultaneous oxidation dyeing method). Second one is dyeing hair by oxidising enzymatically the precursor on hair, which is pre-treated with a bio-catechol solution (post-oxidation dyeing method). The results show that the bio-catechols except EA are oxidised to give colourants and Cat, EC, DOPA, HX and BZ are available for hair dyeing. Overall, the dyeability of simultaneous oxidation dyeing method is higher than that of post-oxidation one. The colour of the hair dyed by simultaneous method is yellowish brown for Cat or EC, grey for DOPA, dark yellowish brown for HX or reddish brown for BZ, respectively. The most vivid or deepest colour of dyed hair is obtained by dyeing with Cat or HX, respectively, in the simultaneous technique. It was found that the bio-catechols having chroman (3, 4-dihydro-2H-1-benzopyran) structure in the molecule such as Cat, EC, HX and BZ are useful for hair colouring.展开更多
Oxidative stress is the key determinant in the pathogenesis of noise-induced hearing loss(NIHL). Given that cellular defense against oxidative stress is an energyconsuming process, the aim of the present study was to ...Oxidative stress is the key determinant in the pathogenesis of noise-induced hearing loss(NIHL). Given that cellular defense against oxidative stress is an energyconsuming process, the aim of the present study was to investigate whether increasing energy availability by glucose supplementation protects cochlear hair cells against oxidative stress and attenuates NIHL. Our results revealed that glucose supplementation reduced the noiseinduced formation of reactive oxygen species(ROS) and consequently attenuated noise-induced loss of outer hair cells, inner hair cell synaptic ribbons, and NIHL in CBA/J mice. In cochlear explants, glucose supplementation increased the levels of ATP and NADPH, as well as attenuating H_2O_2-induced ROS production and cytotoxicity. Moreover, pharmacological inhibition of glucose transporter type 1 activity abolished the protective effects of glucose against oxidative stress in HEI-OC1 cells. These findings suggest that energy availability is crucial for oxidative stress resistance and glucose supplementation offers a simple and effective approach for the protection of cochlear hair cells against oxidative stress and NIHL.展开更多
Oxidative hair dyes containingρ-phenylenediamine(PPD)are reported to induce an allergic reaction by promoting oxidative stress when absorbed through the skin.Despite the associated risk,these hair dyes remain popular...Oxidative hair dyes containingρ-phenylenediamine(PPD)are reported to induce an allergic reaction by promoting oxidative stress when absorbed through the skin.Despite the associated risk,these hair dyes remain popular owing to their convenience and sharpness of color.This makes it important to minimize the cytotoxicity and oxidative stress induced by PPD-containing hair dyes.Ecklonia cava extract has been evaluated in different studies for its protective effects against external stress in fibroblasts and keratinocytes.Our study was aimed at using in-vitro and in-vivo models to investigate the extract’s effects on cytotoxicity of and oxidative stress induced by PPD-containing hair dyes.Analysis of CIEL*a*b*Color space was first used to determine the range of E.cava extract that would not interfere with the coloring ability of the dye upon addition.Subsequently,the set ranges of E.cava extract(5% and 7%)were added to the hair dye and their toxicity assessed by evaluating the viability of fibroblasts and keratinocytes.The effects on developmental phenotypes and induction of oxidative stress by hair dye were evaluated and compared with those of hair dyes containing different contents of E.cava extract using an in-vivo zebrafish model.Our results showed that E.cava extract in hair dye could significantly decrease the cytotoxicity and levels of oxidative stress caused by hair dyes containing PPD in both in-vitro and in-vivo models.These results suggest that the addition of 7% E.cava extract to 250μg/mL hair dye does not interfere with the coloring ability of the dye while showing significant protective eff ects against the hair dye.The study proposes that the use of E.cava extract as an adduct to hair dyes containing PPD reduces the cytotoxicity and oxidative stress induced by these hair dyes.展开更多
Background:Cochlear hair cell injury is a common pathological feature of hearing loss.The basic helix-loop-helix family,member e40(Bhlhe40),a gene belonging to the basic helix-loop-helix(bHLH)family,exhibits strong tr...Background:Cochlear hair cell injury is a common pathological feature of hearing loss.The basic helix-loop-helix family,member e40(Bhlhe40),a gene belonging to the basic helix-loop-helix(bHLH)family,exhibits strong transcriptional repression activity.Methods:Oxidative damage,in House Ear Institute-Organ of Corti 1(HEI-OC1)cells,was caused using hydrogen peroxide(H2O2).The Ad-Bhlhe40 particles were constructed to overexpress Bhlhe40 in HEI-OC1 cells.Various assays including cell counting kit-8(CCK-8),terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay(TUNEL),flow cytometry,immunofluorescence,and corresponding commercial kits were employed to investigate the impacts of Bhlhe40 on cell viability,apoptosis,oxidative stress levels,mitochondrial membrane potential and cellular senescence.Additionally,a dual-luciferase reporter assay was performed to confirm the targeting of the histone deacetylases 2(Hdac2)by Bhlhe40.Results:The results revealed that Bhlhe40 was downregulated in H_(2)O_(2)-treated HEI-OC1 cells,but its overexpression improved cell viability and mitigated H_(2)O_(2)-induced oxidative injury in HEI-OC1 cells with increase of superoxide dismutase(SOD),catalase(CAT)and glutathione peroxidase(GPx)activities and decrease of reactive oxygen species(ROS)levels.Besides,overexpression of Bhlhe40 suppressed H_(2)O_(2)-triggered cell senescence,as evidenced by the fact that the upregulation of P53,P21,and P16 in HEI-OC1 cells treated with H2O2 were all alleviated by Bhlhe40 overexpression.And we further verified that overexpression of Bhlhe40 could inhibit the expression of Hdac2,which may be related to the repression of Hdac2 transcription.Conclusion:This study suggests that Bhlhe40 plays a protective role against senescence and oxidative damage in cochlear hair cells exposed to H2O2.展开更多
文摘The enzymatic oxidation of (+)-catechin (Cat) with copper-containing oxidase, tyrosinase, was applied to hair colouring in the study. The Cat is oxidised to be o-benzoquinone form, the catechinone, which works as the hair dyestuff. Four kinds of hair colouring techniques using Cat were examined and each of their dyeability was compared in order to improve it. The first dyeing method is dyeing hair by the redissolved catechinone, which is preliminarily obtained by the oxidation of Cat (Redissolution Dyeing Method). The second one is dyeing hair in the dye solution just after the dye being formed by the enzymatic reaction (Sequential Dyeing Method). The third one is dyeing hair in solution containing Cat and the dyeing process is accompanied by the oxidation of Cat (Simultaneous Oxidation Dyeing Method). The fourth one is two-step dyeing that the hair immersed in Cat solution at the first step and then it is oxidised enzymatically to colour at the second step (Post-Oxidation Dyeing Method). The hair is dyed pale yellow by Redissolution Method, deeper yellowish brown by Sequential and Simultaneous Oxidation Dyeing Method and slightly reddish brown by Post-Oxidation Method with Cat. The order of their dyeability is the Simultaneous Oxidation ≈ Post-Oxidation > Sequential > Redissolution Dyeing Method at 30°C. The dyeability of Redissolution Method increases with an increase in dyeing temperature (T) between 20°C - 60°C. In Simultaneous Oxidation Method, the T increment also provides higher dyeability, and the colour of dyed hair becomes duller over 50°C. The Post-Oxidation Method shows higher dyeability at the lower oxidation temperature (20 °C - 40°C).
文摘In the study, hair colouring by utilising enzymatic oxidation of nine species of bio-catechols, which are biobased materials having the catechol (o-dihydroxybenzene) group, was examined. The bio-catechols used are (+)-catechin (Cat), (-)-epicatechin (EC), L-3,4-dihydroxyphenylalanine (DOPA), hematoxylin (HX), brazilin (BZ), rosmarinic acid (RA), caffeic acid (CA), chlorogenic acid (ChA) or ellagic acid (EA). The dyeability of human white hair samples dyed by two kinds of dyeing methods using the bio-catechols was compared. First one is dyeing hair during the enzymatic oxidation of a bio-catechol dye precursor in a dye solution (simultaneous oxidation dyeing method). Second one is dyeing hair by oxidising enzymatically the precursor on hair, which is pre-treated with a bio-catechol solution (post-oxidation dyeing method). The results show that the bio-catechols except EA are oxidised to give colourants and Cat, EC, DOPA, HX and BZ are available for hair dyeing. Overall, the dyeability of simultaneous oxidation dyeing method is higher than that of post-oxidation one. The colour of the hair dyed by simultaneous method is yellowish brown for Cat or EC, grey for DOPA, dark yellowish brown for HX or reddish brown for BZ, respectively. The most vivid or deepest colour of dyed hair is obtained by dyeing with Cat or HX, respectively, in the simultaneous technique. It was found that the bio-catechols having chroman (3, 4-dihydro-2H-1-benzopyran) structure in the molecule such as Cat, EC, HX and BZ are useful for hair colouring.
基金supported by the National Natural Science Foundation of China (81570916, 81771018, and 81873699)。
文摘Oxidative stress is the key determinant in the pathogenesis of noise-induced hearing loss(NIHL). Given that cellular defense against oxidative stress is an energyconsuming process, the aim of the present study was to investigate whether increasing energy availability by glucose supplementation protects cochlear hair cells against oxidative stress and attenuates NIHL. Our results revealed that glucose supplementation reduced the noiseinduced formation of reactive oxygen species(ROS) and consequently attenuated noise-induced loss of outer hair cells, inner hair cell synaptic ribbons, and NIHL in CBA/J mice. In cochlear explants, glucose supplementation increased the levels of ATP and NADPH, as well as attenuating H_2O_2-induced ROS production and cytotoxicity. Moreover, pharmacological inhibition of glucose transporter type 1 activity abolished the protective effects of glucose against oxidative stress in HEI-OC1 cells. These findings suggest that energy availability is crucial for oxidative stress resistance and glucose supplementation offers a simple and effective approach for the protection of cochlear hair cells against oxidative stress and NIHL.
文摘Oxidative hair dyes containingρ-phenylenediamine(PPD)are reported to induce an allergic reaction by promoting oxidative stress when absorbed through the skin.Despite the associated risk,these hair dyes remain popular owing to their convenience and sharpness of color.This makes it important to minimize the cytotoxicity and oxidative stress induced by PPD-containing hair dyes.Ecklonia cava extract has been evaluated in different studies for its protective effects against external stress in fibroblasts and keratinocytes.Our study was aimed at using in-vitro and in-vivo models to investigate the extract’s effects on cytotoxicity of and oxidative stress induced by PPD-containing hair dyes.Analysis of CIEL*a*b*Color space was first used to determine the range of E.cava extract that would not interfere with the coloring ability of the dye upon addition.Subsequently,the set ranges of E.cava extract(5% and 7%)were added to the hair dye and their toxicity assessed by evaluating the viability of fibroblasts and keratinocytes.The effects on developmental phenotypes and induction of oxidative stress by hair dye were evaluated and compared with those of hair dyes containing different contents of E.cava extract using an in-vivo zebrafish model.Our results showed that E.cava extract in hair dye could significantly decrease the cytotoxicity and levels of oxidative stress caused by hair dyes containing PPD in both in-vitro and in-vivo models.These results suggest that the addition of 7% E.cava extract to 250μg/mL hair dye does not interfere with the coloring ability of the dye while showing significant protective eff ects against the hair dye.The study proposes that the use of E.cava extract as an adduct to hair dyes containing PPD reduces the cytotoxicity and oxidative stress induced by these hair dyes.
基金This research was supported by the Special Fund for Economic and Technological Development of Longgang District,Shenzhen(LGKCYLWS2021000030).
文摘Background:Cochlear hair cell injury is a common pathological feature of hearing loss.The basic helix-loop-helix family,member e40(Bhlhe40),a gene belonging to the basic helix-loop-helix(bHLH)family,exhibits strong transcriptional repression activity.Methods:Oxidative damage,in House Ear Institute-Organ of Corti 1(HEI-OC1)cells,was caused using hydrogen peroxide(H2O2).The Ad-Bhlhe40 particles were constructed to overexpress Bhlhe40 in HEI-OC1 cells.Various assays including cell counting kit-8(CCK-8),terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay(TUNEL),flow cytometry,immunofluorescence,and corresponding commercial kits were employed to investigate the impacts of Bhlhe40 on cell viability,apoptosis,oxidative stress levels,mitochondrial membrane potential and cellular senescence.Additionally,a dual-luciferase reporter assay was performed to confirm the targeting of the histone deacetylases 2(Hdac2)by Bhlhe40.Results:The results revealed that Bhlhe40 was downregulated in H_(2)O_(2)-treated HEI-OC1 cells,but its overexpression improved cell viability and mitigated H_(2)O_(2)-induced oxidative injury in HEI-OC1 cells with increase of superoxide dismutase(SOD),catalase(CAT)and glutathione peroxidase(GPx)activities and decrease of reactive oxygen species(ROS)levels.Besides,overexpression of Bhlhe40 suppressed H_(2)O_(2)-triggered cell senescence,as evidenced by the fact that the upregulation of P53,P21,and P16 in HEI-OC1 cells treated with H2O2 were all alleviated by Bhlhe40 overexpression.And we further verified that overexpression of Bhlhe40 could inhibit the expression of Hdac2,which may be related to the repression of Hdac2 transcription.Conclusion:This study suggests that Bhlhe40 plays a protective role against senescence and oxidative damage in cochlear hair cells exposed to H2O2.
