title: Parkinson disease and progressive supranuclear palsy: protein expression in skin.
abstract: This study characterizes the expression of tau (p-tau) and α-synuclein (α-syn) by immunohistochemistry in the skin of three different populations: healthy control (HC), Parkinson disease (PD), and progressive supranuclear paralysis (PSP) subjects, with the purpose of finding a biomarker that could differentiate between subjects with PD and PSP.
  
  
  
  We evaluated the presence of p-tau and α-syn in a pilot study in the skin of three distinct groups of patients: 17 healthy subjects, 17 patients with PD, and 10 patients with PSP. Four millimeters punch biopsies were obtained from the occipital area and analyzed by immunohistochemistry using antibodies against α-syn and phosphorylated species of tau. PHF (paired helical filaments) antibody identifies p-tau in both normal and pathological conditions and AT8 recognizes p-tau characteristic of pathological conditions. Differences between the three groups were assessed by quantification of immunopositive areas in the epidermis.
  
  
  
  The immunopositivity pattern of p-tau and α-syn was significantly different among the three groups. Healthy subjects showed minimal staining using AT8 and α-syn. The PD group showed significantly higher α-syn and AT8 immunopositivity, while the PSP group only expressed higher AT8 immunopositivity than HCs.
  
  
  
  These data suggest that the skin reflects brain pathology. Therefore, immunohistochemical analysis of p-tau and α-syn in the skin can be useful for further characterization of PD and PSP.
authors.affiliation: Servicio de Neurología Hospital Central "Ignacio Morones Prieto"San Luis Potosí México; Doctorado en Ciencias Aplicadas Universidad Autónoma de San Luis Potosí San Luis Potosí México.
authors.forename: Ildefonso
authors.initials: I
authors.lastname: Rodríguez-Leyva
authors.affiliation: Departamento de Bioquímica Facultad de Medicina Universidad Autónoma de San Luis Potosí San Luis Potosí México.
authors.forename: Erika G
authors.initials: EG
authors.lastname: Chi-Ahumada
authors.affiliation: Departamento de Bioquímica Facultad de Medicina Universidad Autónoma de San Luis Potosí San Luis Potosí México.
authors.forename: Juan
authors.initials: J
authors.lastname: Carrizales
authors.affiliation: Instituto Nacional de Neurología y Neurocirugía "Manuel Velasco Suárez" México.
authors.forename: Mayela
authors.initials: M
authors.lastname: Rodríguez-Violante
authors.affiliation: Instituto Nacional de Neurología y Neurocirugía "Manuel Velasco Suárez" México.
authors.forename: Salvador
authors.initials: S
authors.lastname: Velázquez-Osuna
authors.affiliation: Servicio de Neurología Hospital Central "Ignacio Morones Prieto" San Luis Potosí México.
authors.forename: Verónica
authors.initials: V
authors.lastname: Medina-Mier
authors.affiliation: Laboratorio de Neurotoxicología Facultad de Ciencias Químicas Universidad Autónoma de San Luis Potosí San Luis Potosí México.
authors.forename: María G
authors.initials: MG
authors.lastname: Martel-Gallegos
authors.affiliation: Laboratorio de Neurotoxicología Facultad de Ciencias Químicas Universidad Autónoma de San Luis Potosí San Luis Potosí México.
authors.forename: Sergio
authors.initials: S
authors.lastname: Zarazúa
authors.affiliation: Departamento de Bioquímica Facultad de Medicina Universidad Autónoma de San Luis Potosí San Luis Potosí México.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Enríquez-Macías
authors.affiliation: Departamento de Bioquímica Facultad de Medicina Universidad Autónoma de San Luis Potosí San Luis Potosí México.
authors.forename: Adriana
authors.initials: A
authors.lastname: Castro
authors.affiliation: Instituto de Medicina Forense Universidad Veracruzana Boca del Río México.
authors.forename: Ana Laura
authors.initials: AL
authors.lastname: Calderón-Garcidueñas
authors.affiliation: Departamento de Bioquímica Facultad de Medicina Universidad Autónoma de San Luis Potosí San Luis Potosí México.
authors.forename: María E
authors.initials: ME
authors.lastname: Jiménez-Capdeville