title: Opioid Receptors in Psoriatic Skin: Relationship with Itch.
abstract: Psoriasis is an inflammatory immunogenetic skin disease, often accompanied by itch. Opioid receptors are known regulators of itch sensation in the central nervous system. In the brain, μ-opioid receptors may potentiate itch, while activation of κ-opioid receptors may reduce or even alleviate itch; however, the role of opioid receptors in itch perception in the skin is poorly understood. To further elucidate the role of opioid receptors in the neurobiology of psoriatic itch, punch biopsies of non-lesional and lesional skin of patients with psoriasis and healthy controls were studied. Real-time polymerase chain reaction and immunofluorescence microscopy were used to detect opioid receptor genes and protein expression, respectively. The OPRK1/κ-opioid receptor pathway was found to be downregulated in lesional skin of psoriasis, correlating positively with itch sensation. In contrast, the OPRM1/μ-opioid receptor system was uniformly expressed by epidermal keratinocytes in all analysed groups. These findings suggest that imbalance of epidermal opioid receptors may result in disordered neuroepidermal homeostasis in psoriasis, which could potentiate transmission of itch.
authors.affiliation: Laboratory of Immunogenetic and Tissues Immunology, Department of Clinical Immunology, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, L. Weigla 12 Street, 53-114 Wroclaw, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Kupczyk
authors.forename: Adam
authors.initials: A
authors.lastname: Reich
authors.forename: Marcin
authors.initials: M
authors.lastname: Hołysz
authors.forename: Mariusz
authors.initials: M
authors.lastname: Gajda
authors.forename: Edyta
authors.initials: E
authors.lastname: Wysokińska
authors.forename: Anna
authors.initials: A
authors.lastname: Kobuszewska
authors.forename: Dmitry
authors.initials: D
authors.lastname: Nevozhay
authors.forename: Beata
authors.initials: B
authors.lastname: Nowakowska
authors.forename: Leon
authors.initials: L
authors.lastname: Strzadała
authors.forename: Paweł Poitr
authors.initials: PP
authors.lastname: Jagodziński
authors.forename: Jacek C
authors.initials: JC
authors.lastname: Szepietowski
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D016022:Case-Control Studies; D004817:Epidermis / Q000737:chemistry* / Q000473:pathology; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D015603:Keratinocytes / Q000737:chemistry; D008297:Male; D008856:Microscopy, Fluorescence; D008875:Middle Aged; D011537:Pruritus / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D011565:Psoriasis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D017473:Receptors, Opioid, kappa / Q000032:analysis* / Q000235:genetics; D017450:Receptors, Opioid, mu / Q000032:analysis* / Q000235:genetics; D012684:Sensory Thresholds; D015398:Signal Transduction; D055815:Young Adult
chemical_list: C515653:OPRK1 protein, human; C485764:OPRM1 protein, human; D012333:RNA, Messenger; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu