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UVB-inhibited H19 activates melanogenesis by paracrine effects
Shiyao Pei1, Jinhua Huang1, Jing Chen1
1Department of Dermatology, Third Xiangya Hospital, Central South University, Changsha, China.
Experimental Dermatology
|July 26, 2018
Summary
UVB irradiation decreases H19 long noncoding RNA in keratinocytes, promoting melanogenesis via paracrine signaling. This study reveals H19
Area of Science:
- Molecular Biology
- Dermatology
- Genetics
Background:
- The long noncoding RNA H19 is implicated in melanogenesis.
- The effect of UVB irradiation on H19 expression and its role in melanocyte regulation via paracrine signaling remain unclear.
Purpose of the Study:
- To investigate UVB-induced changes in H19 expression in keratinocytes.
- To explore the mechanism by which H19 influences melanocyte melanogenesis through paracrine effects.
Main Methods:
- Keratinocytes were exposed to UVB irradiation, and H19, pro-opiomelanocortin (POMC), and α-melanocyte-stimulating hormone (α-MSH) expression were analyzed.
- H19 was silenced using siRNAs in keratinocytes, and subsequent changes in POMC, α-MSH, and p53 expression were assessed.
- Supernatants from H19-silenced keratinocytes were co-cultured with melanocytes (PIG1) to evaluate effects on melanogenesis-related gene expression (MiTF, TYR, Rab27A, TYRP2, FSCN1, MYO5A).
Main Results:
- UVB irradiation decreased H19 expression in keratinocytes but increased POMC, α-MSH, and p53 levels.
- Silencing H19 in keratinocytes significantly upregulated POMC, α-MSH, and p53.
- Co-culture with supernatants from H19-silenced keratinocytes led to increased expression of MiTF, TYR, and Rab27A in melanocytes.
Conclusions:
- UVB-induced downregulation of H19 in keratinocytes may enhance α-MSH secretion, potentially mediated by p53.
- This paracrine signaling pathway involving H19 and α-MSH influences melanocyte melanogenesis.
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