title: The secreted Klotho protein restores phosphate retention and suppresses accelerated aging in Klotho mutant mice.
abstract: Klotho was identified as the responsible gene in a mutant mouse line whose disruption results in a variety of premature aging-related phenotypes. Nonetheless, the related mechanisms were still unknown. Many studies report that dietary phosphate restriction and genetic ablation of vitamin D pathways indirectly reverse premature aging processes in these mice. Furthermore, transgenic overexpression of klotho in mice extends their life span through inhibition of insulin and IGF1 signaling. We found that intraperitoneal injection of recombinant soluble Klotho protein at dose of 0.02 mg/kg every other day effectively extends the life span of kl/kl mice by 17.4%. Soluble Klotho administration also ameliorated premature aging-related phenotype, such as growth retardation, premature thymus involution and vascular calcification, and effectively enhanced urinary phosphate excretion in kl/kl mice. Klotho treatment attenuated renal fibrosis through down-regulation of transforming growth factor-β signaling as well as reduced cellular senescence through down-regulation of p21-cip1 mRNA levels. In addition, soluble Klotho treatment significantly reduced both renal and aorta calcium deposits. In conclusion, our study shows the therapeutic potential of soluble Klotho protein to treat age-related disorders in mice.
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, No 111, Section 3 Hsin-Long Road, Wen-Shang District, Taipei, Taiwan.
authors.forename: Tso-Hsiao
authors.initials: TH
authors.lastname: Chen
authors.forename: Makoto
authors.initials: M
authors.lastname: Kuro-O
authors.forename: Cheng-Hsien
authors.initials: CH
authors.lastname: Chen
authors.forename: Yuh-Mou
authors.initials: YM
authors.lastname: Sue
authors.forename: Yen-Cheng
authors.initials: YC
authors.lastname: Chen
authors.forename: Ho-Han
authors.initials: HH
authors.lastname: Wu
authors.forename: Chung-Yi
authors.initials: CY
authors.lastname: Cheng
mesh_terms: D000054:Acceleration; D000375:Aging / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D000595:Amino Acid Sequence; D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D016466:CHO Cells; D002113:Calcification, Physiologic / Q000187:drug effects; D016922:Cellular Senescence / Q000187:drug effects; D006224:Cricetinae; D003412:Cricetulus; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism; D005355:Fibrosis; D005966:Glucuronidase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology*; D007668:Kidney / Q000166:cytology / Q000378:metabolism / Q000473:pathology / Q000502:physiology; D000090265:Klotho Proteins; D008136:Longevity / Q000187:drug effects; D051379:Mice; D009154:Mutation; D010641:Phenotype; D010710:Phosphates / Q000378:metabolism*; D051381:Rats; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism
chemical_list: D050759:Cyclin-Dependent Kinase Inhibitor p21; D010710:Phosphates; D016212:Transforming Growth Factor beta; D005966:Glucuronidase; D000090265:Klotho Proteins