Exercise preconditioning prevents MCT-induced right ventricle remodeling through the regulation of TNF superfamily cytokines.

BACKGROUND

Exercise training has been recognized as a non-pharmacological therapeutic approach in several chronic diseases; however it remains to be tested if exercise preconditioning can positively interfere with the natural history of pulmonary arterial hypertension (PAH). This is important since the majority of these patients are diagnosed at advanced stages of the disease, when right ventricle (RV) impairment is already present.

OBJECTIVES

In the current study, we evaluated the preventive effect of exercise preconditioning on RV failure secondary to PAH, with a focus on the signaling pathways modulated by pro-inflammatory cytokines from TNF superfamily.

METHODS

We analyzed the RV muscle from adult male Wistar rats exposed to a 4-week treadmill exercise training or sedentary regime, prior to the administration of monocrotaline (MCT) to induce PAH or with saline solution (controls).

RESULTS

Data indicate that exercise preconditioning prevented cardiac hypertrophy and RV diastolic dysfunction. At a molecular level, exercise modulated the TWEAK/NF-κB signaling axis and prevented the shift in MHC isoforms towards an increased expression of beta-MHC. Exercise preconditioning also prevented the increase of atrogin-1 expression, and induced a shift of MMP activity from MMP-9 to MMP-2 activity.

CONCLUSIONS

Altogether, data support exercise as a preventive strategy for the management of PAH, which is of particular relevance for the familial form of PAH that is manifested by greater severity or earlier onset.