The effect of Q10 and vitamin E, separately or in combination, on memory function, and hippocampal oxidative stress and apoptosis of the male miceexposed to heat stress

Abstract

This study aimed to evaluate the effect of coenzyme Q10 and vitamin E administration, alone and in combination, on anxiety- and- depressive-like behaviors and the expression of inflammatory proteins in the hippocampus of adult male mice subjected to heat stress. Methods: Sixty male Balb/c mice were used in this study. One week after acclimation to the laboratory environment, the animals were randomly divided into five groups of 12 mice, including control, heat stress receiving normal saline (NS), heat stress + Q10 (Q10), heat stress + vitamin E (Vit E), and the combined group (Q10 +Vit E). The animals in the heat stress groups were daily subjected to heat stress at 43°C for 15 min for 14 consecutive days, while the animals in the control group were placed in the switched off device. The control and heat stress groups received daily normal saline through gavage. In the 3rd to 5th groups, Q10 (500 mg/kg), vitamin E (250 mg/kg) and a combination of Q10 and vitamin E were administered by gavage for 14 consecutive days. Twenty-four hours after the last exposure to heat stress and receiving the corresponding treatment, anxiety-like behaviors were investigated in elevated plus-maze (EPM) and open field test (OFT). Forced swim test (FST) and tail suspension test (TST) were performed to evaluate depression-like behaviors. At the end, the hippocampus of the animals was removed under deep anesthesia and the expression of inflammatory proteins including NF-kB, NLRP3, Caspase 1, and IL-1β was analyzed by western blot method. In addition, corticosterone serum level was measured by ELISA method and hippocampal hsp70 mRNA expression was measured by Real-time PCR method. Results: The results of EPM test showed that treatment with Q10 and vitamin E, alone and in combination, significantly increased open arms time time (OAT) and the number of open arms entries (OAE) compared to the NS group. Also, these treatments increased the time spent in the center, the number of center entrance, and the number of rearing, while decreased grooming in the OFT test. In addition, Q10 and vitamin E, alone and in combination, decreased immobility time of animals in the FST and TST test compared to the NS group. Moreover, Q10 and vitamin E, alone and in combination, reduced serum corticosterone levels and down-regulated hsp70 expression in heat stress-exposed animals. Furthermore, protein expression of NF-κB, NLRP3, caspase 1, and IL-1β were markedly decreased by Q10and vitamin E, alone and together, in the hippocampus of heat stress-subjected mice.