Dalma Kellermayer1, Attila Oláh1, Csaba Mátyás1, Mihály Ruppert1, Bálint András Barta1, Alex Ali Sayour1, Marianna Török1, Gábor Koncsos2, Zoltán Giricz2, Péter Ferdinándy2, Béla Merkely1, Tamás Radovits1
1 Herat and Vascular Center, Semmelweis University, Budapest
2 Department of Pharmacology and Pharmacotherapy, Semmelweis University, Budapest
Long-term exercise training is associated with characteristic morphological and functional cardiac changes, termed athlete’s heart. Recent studies suggest that sex hormones may be involved in the regulation of exercise-induced left ventricular (LV) hypertrophy. Our aim is to understand the sex-specific alterations in the heart and the underlying signaling pathways following a training period in a rat model.
Male and female rats were divided into control and swimmer groups. Athlete’s heart was induced by a 12-week-long swim training. Following the training period LV hypertrophy was assessed by echocardiography. LV pressure-volume (P-V) analysis was performed to examine in vivo cardiac function. Finally, molecular biological studies (qRT-PCR, Western blot) were performed.
Echocardiography and post-mortem measured LV weights confirmed LV hypertrophy in both genders, nevertheless it was more pronounced in females. Although there is a more significant LV hypertrophy in females, characteristic functional parameters of athletes’s heart did not show notable differences between the genders. P-V analysis showed improved contractility, mechanoenergetics and unaltered LV stiffness in both males and females. Molecular biological measurements showed a more significant induction of Akt signaling in females. There is also a characteristic sex difference in the mitogen-activated protein kinase (MAPK) pathway. The α-myosin heavy chain (MHC)/β-MHC ratio did not differ in males but increased significantly in females.
Our results confirm a more significant exercise-induced LV hypertrophy in females that has no major functional consequences compared to males. The sex-specific response of the LV to exercise is modulated by characteristic molecular pathways.
Doctoral School: Basic Medicine
Program: Cardiovascular Disorders: Physiology and Medicine of Ischaemic Circulatory Diseases
Supervisor: Tamás Radovits
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