References Values of Soluble α-Klotho Serum Levels Using an Enzyme-Linked Immunosorbent Assay in Healthy Adults Aged 18–85 Years

• Main Authors: Amaro-Gahete, F.J (Author), Castillo, M.J (Author), de Haro-Muñoz, T. (Author), de Haro-Romero, T. (Author), Díaz-Alberola, I. (Author), Espuch-Oliver, A. (Author), Jurado-Fasoli, L. (Author), López-Velez, M.S (Author), Vázquez-Lorente, H. (Author)
• Format: Article
• Language: English
• Published: MDPI 2022
• Subjects: aging; ELISA; references values; α-Klotho protein
• Online Access: View Fulltext in Publisher

 α-Klotho protein is a powerful predictor of the aging process and lifespan. Although lowered circulating soluble α-Klotho levels have been observed in aged non-healthy individuals, no specific reference values across a wide range of ages and sex using an enzyme-linked immunosorbent assay (ELISA) are available for larger cohorts of healthy individuals. The present analytical crosssectional study was aimed to establish the reference values of soluble α-Klotho serum levels in healthy adults by age and sex groups. A total of 346 (59% women) healthy individuals aged from 18 to 85 years were recruited. Subjects were divided by sex and age as: (i) young (18–34.9 years), (ii) middleaged (35–54.9 years), and (iii) senior (55–85 years) individuals. The soluble α-Klotho levels were measured in serum using ELISA. Senior adults were the age-group that presented the lowest soluble α-Klotho serum levels (p < 0.01), with age showing a negative association with soluble α-Klotho serum levels (p < 0.001). No differences between sexes were observed. Therefore, soluble α-Klotho levels were especially decreased—regardless of sex—in our cohort of healthy individuals because of the physiological decline derived from the aging process. We recommend routine assessments of soluble α-Klotho levels using ELISA as a simple and cheap detectable marker of aging that improves quality of life in the elderly. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.