Exp Neurobiol.  2017 Jun;26(3):132-140. 10.5607/en.2017.26.3.132.

High-Fat Diet and Voluntary Chronic Aerobic Exercise Recover Altered Levels of Aging-Related Tryptophan Metabolites along the Kynurenine Pathway

• Lee KJ
• Jung KH
• Cho JY
• Lee ST
• Kim HS
• Shim JH
• Lee SK
• Kim M
• Chu K

• KMID: 2383782
• DOI: http://doi.org/10.5607/en.2017.26.3.132

Abstract

Tryptophan metabolites regulate a variety of physiological processes, and their downstream metabolites enter the kynurenine pathway. Age-related changes of metabolites and activities of associated enzymes in this pathway are suggestable and would be potential intervention targets. Blood levels of serum tryptophan metabolites in C57BL/6 mice of different ages, ranging from 6 weeks to 10 months, were assessed using high-performance liquid chromatography, and the enzyme activities for each metabolic step were estimated using the ratio of appropriate metabolite levels. Mice were subjected to voluntary chronic aerobic exercise or high-fat diet to assess their ability to rescue age-related alterations in the kynurenine pathway. The ratio of serum kynurenic acid (KYNA) to 3-hydroxylkynurenine (3-HK) decreased with advancing age. Voluntary chronic aerobic exercise and high-fat diet rescued the decreased KYNA/3-HK ratio in the 6-month-old and 8-month-old mice groups. Tryptophan metabolites and their associated enzyme activities were significantly altered during aging, and the KYNA/3-HK ratio was a meaningful indicator of aging. Exercise and high-fat diet could potentially recover the reduction of the KYNA/3-HK ratio in the elderly.

Keyword

tryptophan metabolites; kynurenine pathway; aging; voluntary chronic aerobic exercise; high-fat diet

MeSH Terms

Aged
Aging
Animals
Chromatography, Liquid
Diet, High-Fat*
Exercise*
Humans
Infant
Kynurenic Acid
Kynurenine*
Mice
Physiological Processes
Tryptophan*
Kynurenic Acid
Kynurenine
Tryptophan