Mechanism of depigmentation by hydroquinone.

  title={Mechanism of depigmentation by hydroquinone.},
  author={Kowichi Jimbow and Hiroto Obata and Madhu A. Pathak and Thomas B. Fitzpatrick},
  journal={The Journal of investigative dermatology},
  volume={62 4},
Histochemical (dopa reaction) and electron microscopic studies were carried out to elucidate the nature of the chemical depigmentation produced by hydroquinone (HQ). Depigmentation was induced by topical application or subcutaneous injection of HQ in black guinea pigs. The present study showed that HQ preferentially affected the nonfollicular and follicular melanocyte system. It caused decreased formation of melanosomes, a marked alteration in the internal structure of melanosomes, an increased… 

Depigmenting action of hydroquinone depends on disruption of fundamental cell processes.

The results suggest that HQ exerts its depigmenting effect by selective action on melanocyte metabolism rather than a specific effect on melanin synthesis.

Exogenous ochronosis and pigmented colloid milium from hydroquinone bleaching creams

The study presented here covers the clinical, histological, histochemical, electron microscopical and pathogenetic features as seen in thirty‐five cases of hydroquinone damage to the dermis in South Africa.

Depigmenting action of phenylhydroquinone, an O-phenylphenol metabolite, on the skin of JY-4 black guinea-pigs.

These morphological and numerical changes in epidermal melanocytes indicate that selective melanocyte toxicity occurred, and confirmed that OPP, which is a reported depigmenter, has little depigmentationing action, while its metabolite, PHQ, is a potent depigmentser preferentially affecting melanocytes.

Chemically Induced Depigmentation of Skin and Hair

The incorporation of melanin pigment into hair is a complex process, involving the multi-stage enzymic synthesis of melanin from tyrosine and its transfer from melanocytes into keratinocytes in the

Reversible Nail Discoloration from Hydroquinone 4 % Cream Thais

It is proposed that hydroquinone inhibits not only the formation, melanization and degradation of melanosomes but also interacts with the membranous structures of melanocytes eventually causing necrosis of whole melanocytes.

Environmentally induced vitiligo (Leucoderma) from depigmenting agents and chemicals

AbstractDepigmentation of the skin due to the melanocytotoxic or melanocytocidal properties of certain chemicals, particularly alkylated phenols and catechols, is now a well recognized and

Glutathione as a depigmenting agent: an overview

In vitro and in vivo studies that show evidence of glutathione involvement in the melanogenic pathway are reviewed and its anti‐melanogenic effect is shed and concepts supported by the various experimental evidence presented form basis for future research in the treatment of pigmentary disorders.

Enhancement of the depigmenting effect of hydroquinone by cystamine and buthionine sulfoximine

The possibility exists that in the future a combination of HQ plus cystamine or BSO could be used to treat disorders such as melasma and post‐Inflammatory hyperpigmentation.

Detection of environmental depigmenting substances

There was no universal solvent or optimal body site, although all tested areas could be depigmented, and a model for screening medicinal and industrial chemicals for depigmenting capacity is proposed.



Topical use of hydroquinone as a depigmenting agent.

Therapy with topically applied hydroquinone did not lead to complete disappearance of pathological hypermelanosis, but results were satisfactory enough to help most patients become less self-conscious about their pigmentary abnormalities.

Selective action of mercaptoethylamines on melanocytes in mammalian skin: experimental depigmentation.

Depigmentation by MEDA appears to result from selective destruction or degeneration of melanocytes, as seen in epidermis from MEDA-treated areas.

Topical use of hydroquinone for depigmentation.

Although the depigmentation produced by topical hydroquinone is limited, it is, in this study, the best available depigmenting agent.

Depigmentation of skin with 4-isopropylcatechol, mercaptoamines, and other compounds.

4-Isopropylcatechol (4-IPC), hitherto unrecognized as a depigmenting agent, appears to be the most potent of all the compounds so far tested and appears to result from a selective action on melanocytes; they are either destroyed or inactivated.

Inhibition of melanin formation by chemical agents.

In this report the inhibition of pigmentation by hydroquinone, monobenzylether of hydroquin one and p-hydroxypropiophenone will be reviewed; and recent studies with these compounds will be presented.

An Electron Microscope Study of Basal Melanocytes and High-Level Clear Cells (Langerhans Cells) in Vitiligo *

It has been established that physiologically active melanocytes, i.e., cells exhibiting dopa or tyrosinase activity on incubation with suitable substrates, are not present in areas of absolute vitiligo, but supra-vital staining of skin from such areas with quinone-imine dyes such as methylene blue, reveals the presence of dendritic cells in the basal layer of the epidermis.

Biochemical basis for depigmentation of skin by phenolic germicides.

It is recommended that chemicals to be included in products that will come into close contact with human skin should be tested for their ability to inhibit tyrosinase.

Depigmentation caused by phenolic detergent germicides.

  • G. Kahn
  • Biology
    Archives of dermatology
  • 1970
From data, it appears that virtually any moderately irritating phenolic compound can depigment skin, but of those tested, paratertiary butyl and amylphenol most often depigmented skin without producing toxic inflammation.

Quantitative and Qualitative Data on the Pigment Cells of Adult Human Epidermis1

The morphology and physiology of the melanocyte have been studied thoroughly by numerous investigators, but conflicting statements concerning several basic points, and insufficient data concerning others were found in recent literature.

The tyrosinases of mouse melanoma. Isolation and molecular properties.

  • J. Burnett
  • Biology
    The Journal of biological chemistry
  • 1971
An effective technique has been developed for isolating and purifying the tyrosinases of mouse melanoma through repeated electrophoresis in urea-containing polyacrylamide gel systems, and it was revealed that enzyme activity was much more sensitive than helical configuration to temperature change.