PP453 - SEX-SPECIFIC RESPONSES IN MUSCLE AND BRAIN FUNCTION AND AMINO ACID KINETICS TO AGING IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) PATIENTS

PP453

SEX-SPECIFIC RESPONSES IN MUSCLE AND BRAIN FUNCTION AND AMINO ACID KINETICS TO AGING IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) PATIENTS

M. C. Kang^1,*, N. E. Deutz^1,2, L. E. Ruebush¹, K. S. Coyle¹, M. P. Engelen^1,2

¹Center for Translational Research in Aging and Longevity, Texas A&M University, ²Primary Care & Rural Medicine, Texas A&M University, College Station, United States

Rationale: Biological sex plays a role in changes in muscle health and amino acid metabolism in patients with Chronic Obstructive Pulmonary Disease (COPD). Whether the trajectories of decline in muscle and brain health and metabolism with aging are affected by biological sex is unclear.

Methods: In 183 moderate to severe COPD: 99 males (50-70y,n=45 vs 70y+,n=44) and 84 females (50-70y,n=47 vs 70y+,n=37), we assessed body composition by DXA, muscle strength by handgrip and isokinetic dynamometry, and cognitive function by Stroop Color and Word Test. A pulse stable amino acid tracers: IV pulse infusion. Plasma amino acid enrichments: LC-MS/MS. Compartmental analysis: intracellular amino acid production and intra/extracellular pool sizes. Stat: GLM and Tukey post hoc.

Results: Although no age effect was found for lean soft tissue, females 70y+ had lower BMI (P=0.026), whereas males 70y+ had higher visceral adipose tissue (P=0.04), compared to 50-70y counterparts. Worse handgrip and leg strength (P=0.058), and cognition (P=0.02) were found in male 70y+. Intracellular production was lower in the 70y+ group for arginine and phenylalanine (P<0.03). Females had lower intracellular production of ornithine and taurine, while that of males was lower in methionine, tryptophan, and tyrosine (all P<0.04) with aging. With aging, lower extracellular pool sizes for arginine and citrulline were found (P<0.05). The extracellular pool was smaller for taurine and phenylalanine, particularly in female 70y+ (P<0.03). Intracellular pool of tau-methylhistidine was greater in 70y+ males (P=0.007).

Conclusion: The aging induced decline in amino acid metabolism in COPD is sex specific. The decline in tryptophan and tyrosine in male COPD patients during aging might be associated with the observed functional decline. Sex-specific treatment needs to be considered when treating COPD patients.

Disclosure of Interest: None declared