Evaluating the effects of exercise and phellodendron amurense on cardiac function in a prostate cancer mouse model

Cytotoxic treatments pose a significant cardiotoxic risk to men with prostate cancer (PCa). Exercise has been found to prevent cardiotoxicities. Previous work from our group has also identified the chemopreventative effects of phellodendron amurense (PhAm). We therefore aimed to compare the effectiveness of exercise ± PhAm on cardiac function in a transgenic PCa mouse model. A 12-wk, four-arm, randomized controlled study was performed. Twenty-four transgenic adenocarcinoma of the mouse prostate mice were randomly assigned to either the control, exercise, PhAm, or exercise with PhAm (ExPhAm) treatment groups. Mice assigned to exercise were given continuous access to a running wheel. PhAm groups consumed a diet enriched with PhAm at 600 mg/kg. Control animals maintained a normal diet and activity. Pre-post echocardiography was performed to measure heart rate, interventricular septum (IVS) thickness, left ventricle (LV) internal diameter, LV volume, ejection fraction, fractional shortening, and left ventricle mass. Exercise, PhAm, and the combination were able to protect against an increase in end-diastolic and end-systolic LV mass (P = 0.003; P = 0.006, respectively). Although not significant, the LV/body mass was markedly higher in the exercise group (+4.5%) and combination (+1.1%) compared with the PhAm (-4.2%) and control groups (-10.3%). Exercise and ExPhAm also protected against increases in IVS thickening, whereas an increase was found in both the PhAm and control groups (P < 0.05). The results of our study suggest that exercise is the driving factor in promoting cardiac health in PCa and can prevent cardiotoxicities associated with the tumor burden.NEW & NOTEWORTHY Exercise is effective in preventing significant left ventricular hypertrophy (when evaluated using relative wall thickness) and promoting a younger mouse phenotype. Exercise was the driving force in the Ex and ExPhAm groups. This resulted in the prevention of significant left ventricular hypertrophy and promotion of a younger mouse phenotype.