Aging-suppressor Klotho: Prospects in diagnostics and therapeutics

•The aging population in the United States and globally is growing.•Klotho is an anti-aging protein with diverse beneficial clinical implications.•Human serum Klotho levels decrease with age in healthy individuals.•Klotho in serum, CSF, urine and certain tissues is lower under specific disease conditions.•To effectively develop Klotho boosting drugs, baseline levels of Klotho are needed.