Concomitant Low Dose Doxorubicin Treatment and Exercise.

Concomitant Low Dose Doxorubicin Treatment and Exercise. Am J Physiol Regul Integr Comp Physiol. 2014 Jul 9; Authors: Sturgeon K, Schadler K, Muthukumaran G, Ding D, Bajulaiye A, Thomas NJ, Ferrari VA, Ryeom S, Libonati JR Abstract Cardiotoxicity is a common side effect for cancer patients treated with doxorubicin (DOX). We tested the hypothesis that low intensity aerobic exercise concomitant with DOX treatment would offset DOX-induced cardiotoxicity while also improving the therapeutic efficacy of DOX on tumor progression. B16F10 melanoma cells (3x10(5)) were injected subcutaneously into the scruff of 6-8 week old male C57BL/6 mice (n= 48). A 4 mg/kg cumulative dose of DOX (IP) was administered over 2 weeks (2 mg/kg, 1 day/week) and exercise (EX) consisted of treadmill walking (10 m/min, 45 min/d, 5 days/week, 2 weeks). Four experimental groups were tested: 1) Sedentary (SED)+Vehicle, 2) SED+DOX, 3) EX+Vehicle, 4) EX+DOX. Tumor volume was attenuated in DOX and lowest in EX+DOX (p<0.05). DOX treated animals also had attenuated body weight gains with reduced heart weights (HW), smaller HW to body weight ratios, and shorter tibial lengths (P<0.05). Despite decreased LV mass with DOX, cardiomyocyte cross sectional area, β myosin heavy chain gene expression, and whole heart systolic (fractional shortening) and diastolic (E/A ratio) function were similar among groups. DOX resulted in increased LV fibrosis (P<0.05) with lower LV ...
Source: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology - Category: Physiology Authors: Tags: Am J Physiol Regul Integr Comp Physiol Source Type: research