Intermedin: A Skin Peptide that Is Downregulated in Atopic Dermatitis.

Intermedin: A Skin Peptide that Is Downregulated in Atopic Dermatitis.

Kindt F, Wiegand S, Loser C, Nilles M, Niemeier V, Hsu SY, Steinhoff M, Kummer W, Gieler U, Haberberger RV.

[1] 1Institute for Anatomy and Cell Biology, University of Giessen, Giessen, Germany [2] 2Department of Psychosomatic Medicine, University of Giessen, Giessen, Germany.

Intermedin (IMD), also called adrenomedullin-2, is a peptide that belongs to the calcitonin/calcitonin gene-related peptide/amylin peptide family. IMD exerts many effects on the cardiovascular system, gastrointestinal tract, and central nervous system. Here, we analyzed the expression of the IMD peptide in human skin of healthy controls, in biopsies from lesional and non-lesional areas of atopic dermatitis (AD) skin, in cultured human keratinocytes, and in the HaCaT keratinocyte cell line at the transcriptional (quantitative reverse transcription-PCR) and translational (immunohistochemistry) level. IMD messenger RNA (mRNA) and protein could be detected in keratinocytes and human skin. Keratinocytes, nerve fibers, periglandular cells, arterial/arteriolar smooth muscle cells, and pericytes of dermal microvessels were intensely IMD-immunoreactive. The IMD mRNA was, compared to healthy skin, significantly reduced in lesional and non-lesional areas of AD skin. This was accompanied by a reduction of IMD immunoreactivity in pericytes of the upper dermis indicating that skin from AD patients is generally affected, and downregulation of IMD in AD skin is not a secondary phenomenon caused by acute inflammation but is a general characteristic of AD skin. These data further point to a role of IMD expressed by pericytes in conferring higher susceptibility of the skin of AD patients to inflammatory stimuli.Journal of Investigative Dermatology advance online publication, 28 September 2006; doi:10.1038/sj.jid.5700576.

J Invest Dermatol. 2006 Sep 28;