Aging-Related Kidney Diseases
Yuichiro Kitai, Masaomi Nangaku, Motoko Yanagita
Abstract
Clinical Background: Older age has been associated with higher prevalence and progression of chronic kidney disease (CKD). The presence of CKD leads to an increased risk of end-stage renal disease, cardiovascular diseases, and death. Epidemiology: Progressive aging of the population is accompanied by an increase in the prevalence of CKD worldwide. The high prevalence of CKD in the aged population would result in a considerably greater social burden. Challenges: Structural and functional changes are often observed in the aged kidney. The main pathological feature of the aged kidney is nephrosclerosis such as arteriosclerosis, glomerulosclerosis, tubular atrophy, and interstitial fibrosis. As a consequence of renal aging, the nephron number decreases. A lower nephron number approximately parallels with the decline in glomerular filtration rate (GFR), and GFR declines with aging. Recent studies have highlighted several pathological mechanisms involved in renal aging, that can serve as targets for intervention. Decreased renal oxygen levels, mitochondrial dysfunction, and inflammation drive renal fibrosis, one of the hallmarks of renal aging. Prevention and Treatment: Novel therapeutic approaches that target these functional changes are now being developed to prevent an aging-associated inevitable loss of renal function. For example, calorie restriction, Sirtuin 1 activator and peroxisome proliferator-activated receptor-γ agonists have the potential to ameliorate renal deterioration. This chapter provides an overview of the aged kidney and summarizes the current knowledge on therapeutic strategies to attenuate renal aging.