title: Regulation of lipid production by acetylcholine signalling in human sebaceous glands.
abstract: BACKGROUND
  The extraneuronal cholinergic system has been implicated in numerous functions in the skin, such as terminal differentiation, barrier formation, sweat secretion and the microcirculation. However, the evidence for cholinergic signalling in sebaceous glands is lacking, and its role needs to be clarified.
  
  
  OBJECTIVE
  We investigated the role of acetylcholine signalling in sebaceous glands using human sebocytes and a clinical study using botulinum toxin.
  
  
  METHODS
  Immunohistochemistry and immunocytofluorescence were performed to evaluate cholinergic receptor levels in sebaceous glands. Lipid levels were assessed by Oil Red O staining and signalling pathways by Western blotting. To evaluate the clinical relevance, we also assessed the effect of botulinum toxin on sebum production in healthy volunteers.
  
  
  RESULTS
  We demonstrated that human skin sebaceous glands in vivo and sebocytes in vitro express nicotinic acetylcholine receptor α7 (nAchRα7), and that acetylcholine increased lipid synthesis in a dose-dependent manner. When sebocytes were incubated with α-bungarotoxin, a competitive nAchR antagonist, acetylcholine failed to up-regulate lipid synthesis. Twenty healthy volunteers were enrolled in a double-blind, placebo-controlled, split-face study. A marked decrease in sebum production on the botulinum-treated side was found in volunteers with oily skin.
  
  
  CONCLUSIONS
  These results provide evidence that acetylcholine signalling plays a significant role in human sebaceous gland biology and identify acetylcholine signalling as a promising target in the clinical management of disorders in which sebum production is increased, such as acne vulgaris.
authors.affiliation: Department of Dermatology, College of Medicine, Chungnam National University, Daejeon, Republic of Korea.
authors.forename: Zheng Jun
authors.initials: ZJ
authors.lastname: Li
authors.forename: Seung Bae
authors.initials: SB
authors.lastname: Park
authors.forename: Kyung Cheol
authors.initials: KC
authors.lastname: Sohn
authors.forename: Young
authors.initials: Y
authors.lastname: Lee
authors.forename: Young Joon
authors.initials: YJ
authors.lastname: Seo
authors.forename: Chang Deok
authors.initials: CD
authors.lastname: Kim
authors.forename: Youn Sung
authors.initials: YS
authors.lastname: Kim
authors.forename: Jeung Hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Myung
authors.initials: M
authors.lastname: Im
mesh_terms: D000109:Acetylcholine / Q000378:metabolism*; D000328:Adult; D001905:Botulinum Toxins / Q000737:chemistry; D002038:Bungarotoxins / Q000737:chemistry; D002454:Cell Differentiation; D004305:Dose-Response Relationship, Drug; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008055:Lipids / Q000096:biosynthesis*; D008297:Male; D008833:Microcirculation; D011950:Receptors, Cholinergic / Q000378:metabolism; D012627:Sebaceous Glands / Q000378:metabolism*; D012629:Sebum / Q000166:cytology; D015398:Signal Transduction; D012867:Skin / Q000378:metabolism; D013997:Time Factors; D055815:Young Adult; D064569:alpha7 Nicotinic Acetylcholine Receptor / Q000378:metabolism
chemical_list: D002038:Bungarotoxins; D008055:Lipids; D011950:Receptors, Cholinergic; D064569:alpha7 Nicotinic Acetylcholine Receptor; D048049:Extracellular Signal-Regulated MAP Kinases; D001905:Botulinum Toxins; D000109:Acetylcholine
keywords: Acetylcholine; Botulinum toxin; Lipid; Sebaceous gland; Sebocyte