ABSTRACT
BACKGROUND: Morphine independently reduces the expression level of Brain-derived Neurotrophic Factor (BDNF) and Cyclic-AMP Response Element Binding protein (CREB). BDNF and CREB play a vital role in protecting and regulating the proper functioning of neurons. There has not been any study on the effect of methadone maintenance treatment and its comparison with morphine. Therefore, this study was conducted to examine the effect of methadone maintenance on the expression of BDNF and CREB genes in brain VTA of male morphine treated rats. METHODS: In this study, 24 Wistar rats (200-250g) were assigned to three experimental groups: 1) Animals without morphine treatment (control); 2) Morphine treated animals (10 mg/kg, twice/day through subcutaneous injection for 21 days); 3) Animals under methadone maintenance after treatment with morphine (maintenance dose of methadone was achieved during 14 days equal to 1 mg per 100 ml at the first week and 2.5 mg per 100 ml at second week). To evaluate the expression of BDNF and CREB genes, real time PCR method was used, and ELISA was applied to measure the serum level of BDNF protein at the end of the experiment. RESULTS: According to the findings of this study, similar to morphine treated group, methadone maintenance in morphine treated animals led to a significant reduction in the expression of BDNF and CREB genes at VTA as well BDNF serum level compared with the control group. CONCLUSION: It was concluded that methadone, like morphine, causes a significant reduction in the expression of BDNF and CREB genes in the brain VTA area of rats as well as BDNF serum level compared with the control group.
Subject(s)
Brain-Derived Neurotrophic Factor , Morphine , Animals , Brain/metabolism , Brain-Derived Neurotrophic Factor/genetics , Brain-Derived Neurotrophic Factor/metabolism , Cyclic AMP Response Element-Binding Protein/genetics , Cyclic AMP Response Element-Binding Protein/metabolism , Male , Methadone/pharmacology , Morphine/pharmacology , Rats , Rats, WistarABSTRACT
Objective: To investigate the effect of crocin carotenoid on BNDF and CREB gene expression in the brain ventral tegmental area (VTA) and the serum level of BDNF in morphine-treated rats compared to control. Methods: In this study, 40 male Wistar rats (200-250 g) were used in 5 experimental groups: 1) non morphine treat rats (control); 2) non morphine-treated rats with 25 mg/kg crocin carotenoid (i.p., for 21 d); 3) morphine treated rats (10 mg/kg twice a day, s.c., 21 d); 4 and 5) morphine-treated rats with 12.5 and 25 mg/kg crocin carotenoid, respectively. By the end of research, BDNF and CREB expression was determined by real-time-PCR method. ELISA analysis was also applied for assessing the serum BDNF level. Results: The data indicated that morphine treatment could cause a significant decrease in BDNF and CREB gene expression (P<0.01 and P<0.001, respectively) in brain VTA as well as serum level of BDNF (P<0.01) in comparison to control group. Treatment with 25 mg/kg crocin carotenoid caused a significant enhancement in BDNF and CREF gene expression (P<0.01 and P<0.05, respectively) and serum level of BDNF (P<0.01) in morphine-treated rats in comparison to morphine-treated group. Conclusions: Regarding to obtained results, crocin carotenoid can inhibit unfavorable effects of morphine on the neural system to some extent through enhancing BDNF and CREB gene expression in brain VTA and serum level of BDNF.
