Acute responses of strength-related gene expressions to maximum strength and force sense acuity

BACKGROUND/AIM: Although high muscle strength worsens the sense of force, it is
unknown whether there is a relationship between this deterioration and the
underlying molecular mechanisms. This study examined the relationship between
decreased force sense (FS) acuity and strength-related gene expressions.
MATERIALS AND METHODS: Maximal voluntary isometric contraction (MVIC) and FS
(50% MVIC) tests were performed on the knee joints of twenty-two subjects. The
expression analyses were evaluated by qRT-PCR in blood samples taken before,
after MVIC, after 50% MVIC, and 15 min after the test.
RESULTS: MVIC and FS error values were significantly correlated with each other
(r = .659, p = .001). The qRT-PCR analyses demonstrated that the expressed mRNAs
of the interleukin 6 (IL-6), alpha-actinin 3 (ACTN3), angiotensin-converting
enzyme (ACE), brain-derived neurotrophic factor (BDNF), and ciliary neurotrophic
factor receptor (CNTFR) genes dramatically increased until 50% MVIC and
subsequently decreased 15 min after the exercise (p < .05). The muscle-specific creatine kinase (CKMM), myosin light chain kinase (MLCK), and G-protein β3 subunit (GNB3) genes reached their peak expression levels 30 min after MVIC (p < .05). ACE and ACTN3 gene expression increased significantly in parallel with the increased FS error (p < .05). These gene expression fluctuations observed at 50% MVIC and after the rest could be related to changes in cellular metabolism leading to fatigue. CONCLUSION: The time points of gene expression levels during exercise need to be considered. The force acuity of those whose maximal force develops too much may deteriorate. © TÜBİTAK. DOI: 10.55730/1300-0144.5775 PMCID: PMC11031174 PMID: 38812641 [Indexed for MEDLINE]