Accelerated telomere attrition in children and teenagers with α1-antitrypsin deficiency

Numerous studies have shown that oxidative stress accelerates telomere shortening in several lung pathologies. Since oxidative stress is involved in the pathophysiology of alpha(1)-antitrypsin deficiency (AATD), we hypothesised that telomere shortening would be accelerated in AATD patients. This study aimed to assess telomere length in AATD patients and to study its association with alpha(1)-antitrypsin phenotypes. Telomere length, telomerase activity, telomerase reverse transcriptase (hTERT) expression and biomarkers of oxidative stress were measured in 62 children and teenagers (aged 2-18 years) diagnosed with AATD and 18 controls (aged 3-16 years). Our results show that intermediate-risk (MZ; SZ) and high-risk (ZZ) AATD patients have significantly shorter telomeres and increased oxidative stress than controls. Correlation studies indicate that telomere length was related to oxidative stress markers in AATD patients. Multiple hypothesis testing revealed an association between telomere length, telomerase activity, hTERT expression and AATD phenotypes; high-risk patients showed shorter telomeres, lower hTERT expression and decreased telomerase activity than intermediate-risk and low-risk patients. AATD patients show evidence of increased oxidative stress leading to telomere attrition. An association between telomere and alpha(1)-antitrypsin phenotypes is observed suggesting that telomere length could be a promising biomarker for AATD disease progression.