title: Soluble αKlotho as a candidate for the biomarker of aging.
abstract: Although the Klotho gene has been recognized as an aging-suppressor gene, the significance of its soluble product, soluble αKlotho (sKlotho), in aging remains to be elucidated. To address this issue, we conducted a single-centered cross-sectional study in a region with a high prevalence of aging. We compared sKlotho levels with the patient characteristics from medical records and laboratory measurements, including fibroblast growth factor 23 (FGF23), intact parathyroid hormone, activated vitamin D3 and factors associated with mineral bone metabolism, in 52 outpatients with a mean age of 78.2 years. Serum sKlotho levels significantly decreased with age, but were not associated with the stage of chronic kidney disease (CKD). Serum FGF23 levels increased as CKD stages advanced, but were not associated with aging. Univariate analyses revealed that sKlotho levels positively correlated with glomerular filtration rate, and negatively with age and serum levels of FGF23 and phosphorus. In a multivariable linear regression analysis, sKlotho significantly correlated with aging and lower FGF23 levels. Only osteoporosis affected sKlotho and FGF23 levels among the various complications and patient status including medication. In summary, serum sKlotho levels inversely correlated with age and FGF23, and were significantly reduced in patients with osteoporosis. sKlotho may serve as a biomarker of aging independent of renal function.
authors.affiliation: Department of Internal Medicine, Fukushima Prefectural Miyashita Hospital, 1150 Minajiri, Mishima, Fukushima 969-7511, Japan; Division of Stem Cell Regulation, Center for Molecular Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Koyama
authors.affiliation: Department of Internal Medicine, Fukushima Prefectural Miyashita Hospital, 1150 Minajiri, Mishima, Fukushima 969-7511, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Sato
authors.affiliation: Department of Internal Medicine, Fukushima Prefectural Miyashita Hospital, 1150 Minajiri, Mishima, Fukushima 969-7511, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Aizawa
authors.affiliation: Department of Internal Medicine, Fukushima Prefectural Miyashita Hospital, 1150 Minajiri, Mishima, Fukushima 969-7511, Japan.
authors.forename: Takumi
authors.initials: T
authors.lastname: Maki
authors.affiliation: Department of Internal Medicine, Fukushima Prefectural Miyashita Hospital, 1150 Minajiri, Mishima, Fukushima 969-7511, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Kurosawa
authors.affiliation: Division of Anti-aging Medicine, Center for Molecular Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Kuro-o
authors.affiliation: Division of Stem Cell Regulation, Center for Molecular Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan. Electronic address: furuyu@jichi.ac.jp.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Furukawa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000235:genetics*; D015415:Biomarkers / Q000378:metabolism*; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005966:Glucuronidase / Q000235:genetics*; D006801:Humans; D000090265:Klotho Proteins; D008297:Male; D012995:Solubility
chemical_list: D015415:Biomarkers; C000717427:FGF23 protein, human; D000089703:Fibroblast Growth Factor-23; D005966:Glucuronidase; D000090265:Klotho Proteins
keywords: Aging; Chronic kidney disease; FGF23; Klotho; Osteoporosis; Soluble αKlotho