Jun Ma1, Xuan Yuan2, Hengyi Qu3, Juan Zhang2, Dong Wang4, Xiling Sun5, Qiusheng Zheng6. 1. Binzhou Medical University, Yantai 264000, Shandong, China; Life Science School, Yantai University, Yantai 264000, Shandong, China. 2. Key Laboratory of Xinjiang Endemic Phytomedicine Resources, Ministry of Education, School of Pharmacy, Shihezi University, Shihezi 832002, Xinjiang, China. 3. Binzhou Medical University, Yantai 264000, Shandong, China. 4. Qianfoshan Hospital of Shandong Province, Jinan 250014, China. 5. Binzhou Medical University, Yantai 264000, Shandong, China. Electronic address: Sunxiling@sohu.com. 6. Binzhou Medical University, Yantai 264000, Shandong, China; Life Science School, Yantai University, Yantai 264000, Shandong, China. Electronic address: zqsyt@sohu.com.
Abstract
AIMS: The alteration of ROS level is frequently observed in the course of morphine addiction, and ROS is proverbially involved in this process. This study aims to explore the relationship among morphine addiction, reactive oxygen species (ROS) and expression of μ-opioid receptor (MOR) in differentiated SH-SY5Y cells. MAIN METHODS: SH-SY5Y cells were induced to differentiation by treatment with retinoic acid (RA); the activity of lactate dehydrogenase (LDH) and the nitro blue tetrazolium (NBT) reduction were assessed by spectrophotometry. Intracellular reactive oxygen species (ROS) was measured with the 2,7-dichlorofluorescin diacetate (DCFH-DA) assay. Cellular cAMP was determined by using a competitive protein binding kit. The mRNA expression of μ-opioid receptor (MOR) was evaluated by qRT-PCR. KEY FINDINGS: Morphine-induced ROS are generated in a concentration- and time-dependent manner and inhibited by naloxone. Exogenous oxidants increase the level of ROS and aggravate morphine addiction, while the exogenous antioxidants efficiently reverse these effects. Morphine decreases the mRNA level of MOR in a concentration-dependent manner. And the mRNA level of MOR is remarkably reduced in the presence of exogenous oxidants and effectively promoted by antioxidants. SIGNIFICANCE: This study indicates that ROS can affect morphine addiction through involving MOR. Treatment with ROS scavenging can serve as a medical therapy for morphine addiction.
AIMS: The alteration of ROS level is frequently observed in the course of morphine addiction, and ROS is proverbially involved in this process. This study aims to explore the relationship among morphine addiction, reactive oxygen species (ROS) and expression of μ-opioid receptor (MOR) in differentiated SH-SY5Y cells. MAIN METHODS: SH-SY5Y cells were induced to differentiation by treatment with retinoic acid (RA); the activity of lactate dehydrogenase (LDH) and the nitro blue tetrazolium (NBT) reduction were assessed by spectrophotometry. Intracellular reactive oxygen species (ROS) was measured with the 2,7-dichlorofluorescin diacetate (DCFH-DA) assay. Cellular cAMP was determined by using a competitive protein binding kit. The mRNA expression of μ-opioid receptor (MOR) was evaluated by qRT-PCR. KEY FINDINGS:Morphine-induced ROS are generated in a concentration- and time-dependent manner and inhibited by naloxone. Exogenous oxidants increase the level of ROS and aggravate morphine addiction, while the exogenous antioxidants efficiently reverse these effects. Morphine decreases the mRNA level of MOR in a concentration-dependent manner. And the mRNA level of MOR is remarkably reduced in the presence of exogenous oxidants and effectively promoted by antioxidants. SIGNIFICANCE: This study indicates that ROS can affect morphine addiction through involving MOR. Treatment with ROS scavenging can serve as a medical therapy for morphine addiction.
Authors: Thangavel Samikkannu; Deepa Ranjith; Kurapati V K Rao; Venkata S R Atluri; Emely Pimentel; Nazira El-Hage; Madhavan P N Nair Journal: Front Microbiol Date: 2015-06-23 Impact factor: 5.640