References Values of Soluble alpha-Klotho Serum Levels Using an Enzyme-Linked Immunosorbent Assay in Healthy Adults Aged 18-85 Years Espuch Oliver, Andrea Vázquez Lorente, Héctor Jurado Fasoli, Lucas Haro Muñoz, Tomás de Díaz Alberola, Irene López Vélez, María del Señor De Haro Romero, Teresa Castillo Garzón, Manuel Amaro Gahete, Francisco José alpha-Klotho protein Aging ELISA References values Hector Vazquez-Lorente (FPU18/03655) and Lucas Jurado-Fasoli (FPU19/01609) are under an FPU fellowship from the Spanish Ministry of Education. This study is part of a Ph.D. thesis conducted in the Biomedicine Doctoral Studies of the University of Granada, Spain. The APC was funded by San Cecilio University Hospital, FIBAO, IBS-Granada, Spain. alpha-Klotho protein is a powerful predictor of the aging process and lifespan. Although lowered circulating soluble alpha-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 cross-sectional study was aimed to establish the reference values of soluble alpha-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) middle-aged (35-54.9 years), and (iii) senior (55-85 years) individuals. The soluble alpha-Klotho levels were measured in serum using ELISA. Senior adults were the age-group that presented the lowest soluble alpha-Klotho serum levels (p < 0.01), with age showing a negative association with soluble alpha-Klotho serum levels (p < 0.001). No differences between sexes were observed. Therefore, soluble alpha-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 alpha-Klotho levels using ELISA as a simple and cheap detectable marker of aging that improves quality of life in the elderly. 2022-06-02T06:13:59Z 2022-06-02T06:13:59Z 2022-04-25 journal article Espuch-Oliver, A... [et al.]. References Values of Soluble alpha-Klotho Serum Levels Using an Enzyme-Linked Immunosorbent Assay in Healthy Adults Aged 18–85 Years. J. Clin. Med. 2022, 11, 2415. [https://doi.org/10.3390/jcm11092415] http://hdl.handle.net/10481/75178 10.3390/jcm11092415 eng http://creativecommons.org/licenses/by/3.0/es/ open access Atribución 3.0 España MDPI