Effect of high-intensity interval training on expression of microRNA-149 and genes regulating mitochondrial biogenesis in doxorubicin-cardiotoxicity in rats

Effect of troxerutin on the expression of genes regulating mitochondrial biogenesis and microRNA-140 in doxorubicin-induced testicular toxicity

Background

Application of doxorubicin (DOX) in cancer patients is limited due to its dose-dependent toxicity to nontarget tissues such as testis and subsequent infertility. Due to limitation of our knowledge about the mechanisms of DOX toxicity in the reproductive system, reduction of DOX-induced testicular toxicity remains an actual and primary clinical challenge. Considering the potentials of troxerutin (TXR) in generating a protective phenotype in many tissues, we aimed to examine the effect of TXR on DOX-induced testicular toxicity by evaluating the histological changes and the expression of mitochondrial biogenesis genes and microRNA-140 (miR-140).

Materials and Methods

Twenty-four adult male Wistar rats (250-300 g) were divided in groups with/without DOX and/or TXR. DOX was injected intraperitoneally at 6 consecutive doses over 12 days (cumulative dose: 12 mg/kg). TXR (150 mg/kg/day; orally) was administered for 4 weeks before DOX challenge. One week after the last injection of DOX, testicular histopathological changes, spermatogenesis activity, and expression of mitochondrial biogenesis genes and miR-140 were determined.

Results

DOX challenge significantly increased testicular histopathological changes, decreased testicular expression profiles of sirtuin 1 (SIRT-1) and nuclear respiratory factor-2 (NRF-2), and increased expression of miR-140 (P < 0.05 to P < 0.01). Pretreatment of DOX-received rats with TXR significantly reversed testicular histopathological changes, spermatogenesis activity index, and the expression levels of SIRT-1, peroxisome proliferator-activated receptor-γ coactivator 1-alpha (PGC-1α), NRF-2, and miR-140 (P < 0.05 to P < 0.01).

Conclusion

Reduction of DOX-induced testicular toxicity following TXR pretreatment was associated with upregulation of SIRT-1/PGC-1α/NRF-2 profiles and better regulation of miR-140 expression. It seems that improving microRNA-mitochondrial biogenesis network can play a role in the beneficial effect of TXR on DOX-induced testicular toxicity.

Effect of troxerutin on oxidative stress and expression of genes regulating mitochondrial biogenesis in doxorubicin-induced myocardial injury in rats

Because of limitation of doxorubicin (DOX) clinical application in chemotherapy due to its cardiotoxicity, finding new strategies to reduce DOX challenge and improve patients' outcomes is crucial. Due to positive cardiovascular impacts of troxerutin (TXR), here we have investigated the effect of TXR on DOX-induced cardiotoxicity by evaluating the myocardial oxidative stress and expression of genes regulating mitochondrial biogenesis. Male Wistar rats (250-300 g) were randomly allocated into four groups: control, TXR, DOX, and TXR + DOX. Troxerutin (150 mg/kg) was orally administrated once a day through a gavage tube for 4 weeks before DOX challenge. The TXR-treated and time-matched control rats received intraperitoneal injection of DOX (20 mg/kg). Three days after DOX challenge, the left ventricular samples were obtained to determine the expression of genes regulating mitochondrial biogenesis via real-time PCR. Myocardial creatine kinase (CK-mB), oxidative stress markers, and mitochondrial function (generation of reactive oxygen species or ROS and ATP levels) were also evaluated using commercial kits and spectrophotometric and fluorometric methods. DOX administration significantly increased the levels of CK-mB, malondialdehyde (MDA), and mitochondrial ROS levels, while reduced the cellular ATP production and expression levels of SIRT-1, PGC-1α, and NRF-2 as well as superoxide dismutase, glutathione peroxidase, and catalase activity in comparison to control group (P < 0.05 to P < 0.01). Pretreatment of DOX-received rats with TXR significantly upregulated the expression of all biogenesis genes and antioxidant enzymes with non-significant effect on catalase activity, and significantly reduced CK-mB and MDA levels toward control values (P < 0.05 to P < 0.01). Mitochondrial ROS and ATP levels were also restored significantly by pretreatment with TXR (P < 0.05). The data suggested that preconditioning of rats with TXR had protective effect on DOX-induced cardiotoxicity through inducing antioxidative properties and restoring the mitochondrial function and the expression profiles of myocardial SIRT-1/PGC-1α/NRF-2 network.