Jing Liu1, Yu Han1, Tao Zhu1, Qing Yang1, Heming Wang2, Hao Zhang2,3. 1. School of Life Science and Bioengineering, Henan University of Urban Construction, Pingdingshan, China. 2. BDAcademic & Research Center, Beidou Life Science Corp. Ltd, Guangzhou, China. 3. Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, China.
Abstract
OBJECTIVE: The traditional Chinese medicine, Dendrobium nobile Lindl. polysaccharides (DNLP), reportedly has neuroprotective effects. However, its effects following ischemic stroke remain unclear. This study aimed to explore the role and mechanism of DNLP in experimental models of inflammation and apoptosis. METHODS: Inflammation and apoptosis were induced by in vivo ischemia/reperfusion and by in vitro oxygen glucose deprivation/reperfusion (OGD/R). In the in vivo model, immediately after the induction of cerebral ischemia, 50, 100, and 200 mg/kg DNLP were injected intraperitoneally. We subsequently detected indicators of neuronal damage. RESULTS: Treatment with Dendrobium nobile Lindl. polysaccharide significantly reduced cerebral ischemic injury. After in vivo and in vitro middle cerebral artery occlusion/reperfusion or OGD/R-induced hypoxia injury, miR-134 expression in neurons was significantly increased. Altering the expression of miR-134 induced changes in myeloid cell leukemia 1 (MCL-1), one of its target proteins. In addition, DNLP significantly downregulated the in vivo and in vitro expression of miR-134 after ischemic injury, and influenced inflammation and apoptotic proteins by altering the level of MCL-1 protein. DNLP also had a protective effect on neurons damaged by OGD/R, which could improve cell survival rates and inhibit lactate dehydrogenase release as well as apoptosis. CONCLUSIONS: DNLP may protect the brain and neurons from hypoxic damage in mice with ischemic stroke by activating MCL-1 and downregulating miR-134, providing a new therapeutic target for ischemic stroke.
OBJECTIVE: The traditional Chinese medicine, Dendrobium nobile Lindl. polysaccharides (DNLP), reportedly has neuroprotective effects. However, its effects following ischemic stroke remain unclear. This study aimed to explore the role and mechanism of DNLP in experimental models of inflammation and apoptosis. METHODS: Inflammation and apoptosis were induced by in vivo ischemia/reperfusion and by in vitro oxygen glucose deprivation/reperfusion (OGD/R). In the in vivo model, immediately after the induction of cerebral ischemia, 50, 100, and 200 mg/kg DNLP were injected intraperitoneally. We subsequently detected indicators of neuronal damage. RESULTS: Treatment with Dendrobium nobile Lindl. polysaccharide significantly reduced cerebral ischemic injury. After in vivo and in vitro middle cerebral artery occlusion/reperfusion or OGD/R-induced hypoxia injury, miR-134 expression in neurons was significantly increased. Altering the expression of miR-134 induced changes in myeloid cell leukemia 1 (MCL-1), one of its target proteins. In addition, DNLP significantly downregulated the in vivo and in vitro expression of miR-134 after ischemic injury, and influenced inflammation and apoptotic proteins by altering the level of MCL-1 protein. DNLP also had a protective effect on neurons damaged by OGD/R, which could improve cell survival rates and inhibit lactate dehydrogenase release as well as apoptosis. CONCLUSIONS: DNLP may protect the brain and neurons from hypoxic damage in mice with ischemic stroke by activating MCL-1 and downregulating miR-134, providing a new therapeutic target for ischemic stroke.