title: Relationship between transient receptor potential vanilloid-1 expression and the intensity of sensitive skin symptoms.
abstract: BACKGROUND
  Sensitive skin (SS) is a hyper-reactive condition of the skin secondary to external factors, without objective signs of lesion. Its pathogenesis is still under investigation. Transient receptor potential vanilloid-1 (TRPV1) is a cation channel that responds to low pH and is related to nociception, neurogenic inflammation, and pruritus.
  
  
  OBJECTIVE
  To determine the expression of TRPV1 in subjects with SS and correlate it with the degree of symptoms and skin pigmentation.
  
  
  METHODS
  We included 31 subjects self-diagnosed as having SS. Colorimetric values were obtained for assessment of skin phototype, and the lactic acid stinging test (LAST) was performed. Two skin biopsies from the nasolabial fold of each volunteer were obtained. Qualitative analysis of TRPV1 was carried out with immunohistochemistry. Quantitative analysis of TRPV1 was carried out with qRT-PCR.
  
  
  RESULTS
  LAST was positive in 74% of the subjects, 56% of those having tan and brown skin. Immunohistochemistry staining for TRPV1 was greater in positive subjects (P = 0.03), but showed no correlation with the intensity of symptoms. Positive subjects also had higher TRPV1 mRNA expression compared to negative subjects (P < 0.001). This expression showed a positive correlation with the intensity of referred symptoms (R = 0.75, P < 0.001) and skin pigmentation (R = 0.63, P < 0.001).
  
  
  CONCLUSIONS
  TRPV1 expression is upregulated in subjects with sensitive skin, and it correlates with the intensity of the symptoms. Our findings suggest a role for this receptor in the pathogenesis of sensitive skin syndrome.
authors.affiliation: Department of Dermatology, Hospital Central Dr. Ignacio Morones Prieto, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México.
authors.forename: Adriana
authors.initials: A
authors.lastname: Ehnis-Pérez
authors.affiliation: Department of Dermatology, Hospital Central Dr. Ignacio Morones Prieto, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México.
authors.forename: Bertha
authors.initials: B
authors.lastname: Torres-Álvarez
authors.affiliation: Laboratory of Immunology, Cellular and Molecular Biology, Chemical Sciences Faculty, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México.
authors.forename: Diego
authors.initials: D
authors.lastname: Cortés-García
authors.affiliation: Department of Dermatology, Hospital Central Dr. Ignacio Morones Prieto, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México.
authors.forename: Diana
authors.initials: D
authors.lastname: Hernández-Blanco
authors.affiliation: Department of Dermatology, Hospital Central Dr. Ignacio Morones Prieto, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Fuentes-Ahumada
authors.affiliation: Department of Dermatology, Hospital Central Dr. Ignacio Morones Prieto, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México.
authors.forename: Juan Pablo
authors.initials: JP
authors.lastname: Castanedo-Cázares
mesh_terms: D000328:Adult; D005260:Female; D015870:Gene Expression; D006801:Humans; D006941:Hyperesthesia / Q000235:genetics* / Q000378:metabolism; D019344:Lactic Acid; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000378:metabolism*; D012720:Severity of Illness Index; D012871:Skin Diseases / Q000235:genetics* / Q000378:metabolism; D012880:Skin Pigmentation; D050916:TRPV Cation Channels / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D012333:RNA, Messenger; D050916:TRPV Cation Channels; C494482:TRPV1 protein, human; D019344:Lactic Acid
keywords: Sensitive skin; TRPV1; gene expression; lactic acid stinging test; phototype