Hacat melanosome transfer

Methyl anthranilate (MA) is a botanical fragrance used in food flavoring with unexplored potential in anti-pigment cosmetics. MA dose-dependently reduced melanin content without affecting cell viability, inhibited dendrite elongation and melanosome transfer in the co-culture system of human melanoma cells (MNT-1) and human keratinocyte cell line (HaCaT), and downregulated melanogenic genes, including tyrosinase, tyrosinase-related protein 1 and 2 (TRP-1, TRP-2). Additionally, MA decreased cyclic adenosine monophosphate (cAMP) production and exhibited a significant anti-pigmentary effect in MelanodermTM ...

Pearl powder is a famous traditional Chinese medicine that has a long history in treating palpitations, insomnia, convulsions, epilepsy, ulcers, and skin lightining. Recently, several studies have demonstrated the effects of pearl extracts on protection of ultraviolet A (UVA) induced irritation on human skin fibroblasts and inhibition of melanin genesis on B16F10 mouse melanoma cells. To further explore the effect we focused on the whitening efficacy of pearl hydrolyzed conchiolin protein (HCP) on human melanoma MNT-1 cells under the irritation of alpha-melanocyte-stimulating hormone ( α -MSH) or endothelin 1 (ET-1) to evaluate the intracellular tyrosinase and melanin contents, as well as the expression levels of tyrosinase ( TYR ), tyrosinase related protein 1 ( TRP-1 ), and dopachrome tautomerase ( DCT ) genes and related proteins...

The melanosome is an organelle that produces melanin for skin pigmentation, which is synthesized by epidermal melanocytes, subsequently transported and internalized by epidermal keratinocytes. Exposure to ultraviolet (UV) from sunlight radiation is a major stimulator of melanosome uptake by keratinocytes. Acetylcholine (ACh) is known to be released by keratinocytes under UV exposure, which regulates melanin production in melanocytes by participating in which has been named as 'skin synapse'. Here, the role of cholinergic molecules, i...

PURPOSE: Ultraviolet radiation (UVR) enhances skin pigmentation, which involves the production of melanin by melanocytes and subsequent transfer to keratinocytes. In the epidermis, keratinocyte phagocytosis plays a pivotal role in the process of melanosome transfer to protect DNA of epidermal cells against damage from UVR. Previous research suggested that transient receptor potential channels ankyrin 1 (TRPA1) was required for UVR-induced early melanin synthesis in melanocytes. Currently, there is no evidence that supports the detailed mechanism of TRPA1 for UVR-induced phagocytosis by keratinocytes...

BACKGROUND: Keratinocytes are recipients of melanosomes. Although the chemical basis of melanogenesis is well documented, the molecular mechanism of melanosome transfer must be elucidated. TRPA1 is a member of the transient receptor potential A subfamily. Previous studies have shown that inhibition of TRPA1 activity reduces melanin synthesis in human epidermal melanocytes; however, the mechanism remains unknown. OBJECTIVE: This study aimed to investigate the roles and mechanism(s) of action of TRPA1 in keratinocytes...

Skin forms a physical barrier that protects the body against outside agents. The deepest layer of the skin, the stratum basale, contains two cell types: agent-sensing keratinocytes, and melanin-producing melanocytes. Keratinocytes can sense both harmless commensal organisms and harmful pathogens via Toll-like receptors (TLRs), and keratinocytes subsequently drive immune responses. Activation of TLR3 is required for barrier repair because it stimulates essential genes, including tight junction genes, and inflammatory cytokines...

Despite the clinical ability of topical tacrolimus (FK506) to effectively promote repigmentation in vitiligo, the underlying mechanism through which FK506 regulates melanogenesis was previously unclear. We found that FK506 treatment increased the melanin contents (especially that of eumelanin) in both melanocytes and melanoma cells. This treatment did not affect the transcription levels of tyrosinase, suggesting that FK506 increases melanin synthesis by regulating cellular levels of tyrosinase. Interestingly, FK506 promoted melanosome maturation by increasing melanosomal pH (a marker of melanosome maturation), thereby enhancing the stability of melanosome-localized tyrosinase...

Skin pigmentation is the result of melanosome transfer from melanocytes to keratinocytes. Protease-activated receptor-2 (PAR-2) is a key mediator of melanosome transfer, which occurs as the melanocyte extends its dendrite toward surrounding keratinocytes that take up melanosomes by phagocytosis. We investigated the effects of macelignan isolated from Myristica fragrans HOUTT. (nutmeg) on melanosome transfer and the regulation of PAR-2 in human keratinocytes (HaCaT). HaCaT cells stimulated by the PAR-2-activating peptide Ser-Leu-Ile-Gly-Arg-Leu-NH₂ (SLIGRL) were treated with macelignan; PAR-2 expression was then determined by reverse transcription-polymerase chain reaction (RT-PCR), Western blot, and immunocytochemistry...

In view of the melanin-binding characteristics of haloperidol and its differential uptake by pigment- and non-pigment-producing cells, a co-culture of HaCaT with Sk-Mel-1 cell lines was performed to investigate whether melanosomes act as carriers for drug molecules associated with the pigments. Initially, HaCaT and Sk-Mel-1 cells were separately cultivated in the presence of 3H-haloperidol (400 pmol/ml medium ) for 28 days followed by subsequent co-cultivation in the absence of 3H-haloperidol for 5 days. The transfer of pigments into the keratinocytes during co-culture was confirmed by transmission electron microscopy...