High-Intensity Training Represses FXYD5 and Glycosylates Na,K-ATPase in Type II Muscle Fibres, Which Are Linked with Improved Muscle K⁺ Handling and Performance.

ABSTRACT: Na⁺/K⁺ ATPase (NKA) comprises several subunits to provide isozyme heterogeneity in a tissue-specific manner. An abundance of NKA α, β, and FXYD1 subunits is well-described in human skeletal muscle, but not much is known about FXYD5 (dysadherin), a regulator of NKA and β1 subunit glycosylation, especially with regard to fibre-type specificity and influence of sex and exercise training. Here, we investigated muscle fibre-type specific adaptations in FXYD5 and glycosylated NKAβ1 to high-intensity interval training (HIIT), as well as sex differences in FXYD5 abundance. In nine young males (23.8 ± 2.5 years of age) (mean ± SD), 3 weekly sessions of HIIT for 6 weeks enhanced muscle endurance (220 ± 102 vs. 119 ± 99 s, p < 0.01) and lowered leg K⁺ release d

SUBMITTER: Hostrup M 

PROVIDER: S-EPMC10051537 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature