Physical decline and survival in the elderly are affected by the genetic variability of amino acid transporter genes

• Published in: Aging (Albany, NY.) Vol. 10; no. 4; pp. 658 - 673
• Main Authors: Crocco, Paolina, Hoxha, Eneida, Dato, Serena, De Rango, Francesco, Montesanto, Alberto, Rose, Giuseppina, Passarino, Giuseppe
• Format: Journal Article
• Language: English
• Published: United States Impact Journals 18.04.2018
• Subjects: Activities of Daily Living; Aged; Aged, 80 and over; Amino Acid Transport Systems - genetics; Cross-Sectional Studies; Female; Genotype; Hand Strength - physiology; Humans; Longevity - genetics; Longitudinal Studies; Male; Middle Aged; Polymorphism, Single Nucleotide; Research Paper; Survival Analysis; Hand grip; ADL; muscle decline; aging; amino acid transporter genes; mTORC1; sarcopenia
• ISSN: 1945-4589; 1945-4589
• DOI: 10.18632/aging.101420

Amino acid (AA) availability is a rate-limiting factor in the regulation of muscle protein metabolism and, consequently, a risk factor for age-related decline in muscle performance. AA transporters are emerging as sensors of AA availability and activators of mTORC1 signalling, acting as transceptors. Here, we evaluated the association of 58 single nucleotide polymorphisms (SNPs) in 10 selected AA transporter genes with parameters of physical performance (Hand Grip, Activity of Daily Living, Walking time). By analysing a sample of 475 subjects aged 50-89 years, we found significant associations with /LAT1, /LAT2, /PAT1, /SNAT2, /CD98, /SNAT7 genes. Further investigation of the SNPs in a cross-sectional study including 290 subjects aged 90-107 years revealed associations of /CD98, /SNAT2, /SNAT3, /SNAT9 variability with longevity. Finally, a longitudinal study examining the survival rate over 10 years showed age-dependent complexity due to possible antagonistic pleiotropic effects for a SNP in /SNAT9, conferring a survival advantage before 90 years of age and a disadvantage later, probably due to the remodelling of AA metabolism. On the whole, our findings support the hypothesis that AA transporters may impact on the age-related physical decline and survival at old age in a complex way, likely through a mechanism involving mTORC1 signalling.