title: Lipid peroxidation is increased in tears from the elderly.
abstract: We describe a procedure in which tears, obtained from Schirmer strips, are used to measure a marker of lipid peroxidation, malondialdehyde (MDA). We also compared the levels of proteins and MDA in tears from two groups of people: young adults (18-30 years old) and elderly adults (65-85 years old), because the data related to total protein concentration of human tears vary widely and because the majority of people over the age of 65 experience some symptoms of dry eyes and this condition has been recognized as an oxidative stress-induced disease. Our results show a significant difference in the protein concentration of the tears taken from the two age categories, younger adults (18-30 years old) and older adults (65-85 years old). Herein, we report for the first time an increase in MDA concentrations determined by HPLC in human tears based on age. It is possible that alterations in the tear lipid layer may lead to an increase in lipid peroxidation. Further studies are needed to understand the nature and function of tear film and stability in order to obtain new methods to analyze tears in patients with different diseases. In this sense, it would be interesting to compare MDA concentration in tears from control subjects and from people with meibomian gland dysfunction.
authors.affiliation: Departamento de Ciencias Biomédicas, Instituto de Ciencias Biomédicas, Universidad CEU Cardenal Herrera, Avda. Seminario s/n, 46113 Moncada, Valencia, Spain.
authors.forename: Soledad
authors.initials: S
authors.lastname: Benlloch-Navarro
authors.forename: Ilenia
authors.initials: I
authors.lastname: Franco
authors.forename: Violeta
authors.initials: V
authors.lastname: Sánchez-Vallejo
authors.forename: Dolores
authors.initials: D
authors.lastname: Silvestre
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Romero
authors.forename: María
authors.initials: M
authors.lastname: Miranda
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D002851:Chromatography, High Pressure Liquid; D005136:Eye Proteins / Q000378:metabolism*; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation / Q000502:physiology*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism*; D008875:Middle Aged; D017678:Sex Distribution; D013666:Tears / Q000378:metabolism*; D055815:Young Adult
chemical_list: D005136:Eye Proteins; C042434:tear proteins; D008315:Malondialdehyde
keywords: age; lipid peroxidation; malondialdehyde; proteins; tears