Effects of Resistance and Endurance Training on HIF-1α and VEGF in Heart Tissues of Pregnant Rats with Cadmium Toxicity

Abstract

Background: Exposure to cadmium can cause cardiovascular disorders, including possible risks of angiogenesis abnormalities associated with Hypoxia Inducible Factor (HIF), in pregnancy period. Objectives: This study aimed to investigate the effects of resistance and endurance training on HIF-1α and vascular endothelial growth factor (VEGF) levels in heart tissue of pregnant rats with cadmium toxicity. Methods: In this study, 48 female rats were selected and divided into 6 groups of 8 rats, including (1) cadmium, (2) resistance training, (3) resistance training with cadmium consumption, (4) endurance training, (5) endurance training with cadmium consumption, and (6) control. Groups 2, 3, 4, and 5 performed three weeks of resistance and endurance training, five sessions per week. Also, groups 1, 3, and 5 received cadmium as cadmium chloride dissolved in water as 400 mg per liter through drinking water. To analyze the data, Kolmogorov-Smirnov, One-way ANOVA, and Tukey’s post hoc tests were used and P ≤ 0.05 was considered statistically significant. Results: Cadmium had a significant effect on the increase of HIF1-α and VEGF (P = 0.001); resistance training had a significant effect on the increase of HIF1-α (P = 0.03), resistance training (P = 0.02) and endurance training (P = 0.001) had a significant effect on the increase of VEGF. Also, resistance training with cadmium consumption as well as endurance training with cadmium consumption significantly decreased HIF1-α (P = 0.001) and VEGF (P = 0.001), compared with cadmium consumption. Conclusions: Cadmium appears to lead to an abnormal increase in HIF-1α and VEGF in the heart tissues of pregnant rats, which can stimulate abnormal angiogenesis of tumors; however, resistance and endurance training can reduce the severity of cadmium effects on abnormal angiogenesis of the heart tissue of pregnant rats.