Evaluation of the expression levels of pulmonary HSP70 and HSP90 in response to taper in hypoxic conditions

Despite the recognition of reduced workload in exercise as a model to increase exercise performance in normal conditions, there is no information on the effect of this training pattern on internal organs in hypoxic conditions. The purpose of this study was to investigate the response of HSP70 and HSP90 proteins to taper in hypoxia. The samples were twenty-four healthy male Wistar rats (8 control and 16 experimental rats) with no history of disease (four-weeks old, 72±9 gr weight). The experimental group were participated in an interval training program for six weeks, and then remained in hypoxic conditions for three weeks. Half of the experimental samples performed taper technique during exposure to the hypoxic environment. At the end of experimental period, the lung tissues of all samples were removed and the expression level of HSP70 and HSP90 proteins were evaluated. One-way ANOVA method was used for data analysis and p≤0.05 was considered as significant. The expression levels of HSP70 and HSP90 were significantly increased in the hypoxia group in contrast to the control group (p≤0.05).In the hypoxia-taper group, also, the expression of HSP70 and HSP90 was decreased significantly compared to the hypoxia group (p≤0.05).  The results show that hypoxia can causes biological stress in lung tissue, leading to lung protective response by increasing the expression of heat-shock proteins, and performing of interval exercise training with less intense in hypoxic conditions may help to maintain lung hemostasis.