Related Experiment Video
Updated: Jun 12, 2026
06:53
Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
Circadian Clock Regulates Epidermal Endocrine System in Homeostatic Skin Pigmentation.
Anya Zhu1,2, Lingli Yang1, Sylvia Lai1
1Department of Pigmentation Research and Therapeutics, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan.
Experimental Dermatology
|June 11, 2026
Summary
The skin's circadian clock influences melanin production. Disrupting core clock genes (BMAL1, CLOCK) reduces melanin synthesis and vitamin D metabolism, potentially linking circadian rhythm to pigmentary disorders like vitiligo.
Area of Science:
- Dermatology
- Chronobiology
- Molecular Biology
Background:
- The skin's circadian clock regulates hormone synthesis and pigmentation.
- The interaction between circadian regulation and melanocyte endocrine signaling is not well understood.
Purpose of the Study:
- To investigate how core circadian regulators affect melanogenesis in human melanocytes.
- To explore the link between circadian regulators, epidermal endocrine factors, and pigmentary diseases.
Main Methods:
- siRNA-mediated knockdown of core clock genes basic helix-loop-helix ARNT-like protein 1 (BMAL1) and CLOCK circadian regulator (CLOCK) in human epidermal melanocytes.
- Analysis of melanin synthesis and expression of hormone-related factors.
- Immunohistochemical analysis of CYP27A1 expression in normal skin and vitiligo lesions.
Main Results:
- Silencing BMAL1 or CLOCK significantly reduced melanin synthesis.
- Knockdown of BMAL1 or CLOCK decreased the expression of the vitamin D-metabolizing enzyme CYP27A1.
- Reduced CYP27A1 expression correlated with decreased melanogenic activity and was observed in vitiligo lesions.
Conclusions:
- Disruption of circadian clock regulators impairs melanogenesis in human melanocytes.
- Circadian clock genes influence pigmentation partly through effects on vitamin D metabolism.
- Findings offer new insights into the mechanisms of pigmentary disorders and the role of circadian rhythm.
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