Jian Li1, Zhiqiang Jia2, Wen Xu3, Weidong Guo1, Mingchao Zhang1, Jing Bi4, Yang Cao1, Zhongkai Fan5, Gang Li6. 1. Department of Orthopedics, The First Affiliated Hospital, Jinzhou Medical University, Jinzhou 121000, China. 2. Department of Spinal Surgery, The Second Affiliated Hospital, Henan University of Science and Technology, Luoyang 471003, China. 3. School of Nursing, Jinzhou Medical University, Jinzhou 121000, China. 4. Department of Neurobiology, Key Laboratory of Neurodegenerative Diseases of Liaoning Province, Jinzhou Medical University, Jinzhou 121000, China. 5. Department of Orthopedics, The First Affiliated Hospital, Jinzhou Medical University, Jinzhou 121000, China. Electronic address: fanzk_ln@163.com. 6. Department of Orthopedics, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China. Electronic address: ganglili@126.com.
Abstract
AIMS: Identifying drugs that inhibit edema and glial scar formation and increase neuronal survival is crucial to improving outcomes after spinal cord injury (SCI). Here, we used 2-(nicotinamide)-1,3,4-thiadiazole (TGN-020), a potent selective inhibitor of aquaporin 4 (AQP4), to investigate the effects of TGN-020 on SCI in Sprague-Dawley rats. MAIN METHODS: We compressed the spinal cord at T10 using a sterile impounder (35 g, 5 min), to induce moderate injury. TGN-020 (100 mg/kg) or an equal volume of 10% dimethyl sulfoxide was then administered via intraperitoneal injection. Neurological function was evaluated using the Basso-Beattie-Bresnahan open-field locomotor scale 1, 3, 7, 14, 21, and 28 days after SCI. The degree of edema was assessed via determination of the precise spinal cord water content 3 days after SCI. Expression levels of AQP4, glial fibrillary acidic protein (GFAP), proliferating cell nuclear antigen (PCNA), and growth-associated protein-43 (GAP-43) were determined via western blotting and immunofluorescence staining 3 days after SCI and 4 weeks after SCI. Numbers of surviving neurons and glial scar sizes were determined using Nissl and hematoxylin-eosin staining, respectively. KEY FINDINGS: Our results showed that TGN-020 promoted functional recovery at days 3, 7, 14, 21, and 28, as well as reduced the degree of edema and inhibited the expression of AQP4, GFAP, PCNA at days 3 after SCI. Furthermore, observations 4 weeks after SCI revealed that TGN-020 inhibited the glial scar formation and upregulated GAP-43 expression. SIGNIFICANCE: TGN-020 can alleviate spinal cord edema, inhibit glial scar formation, and promote axonal regeneration, conferring beneficial effects on recovery in rats.
AIMS: Identifying drugs that inhibit edema and glial scar formation and increase neuronal survival is crucial to improving outcomes after spinal cord injury (SCI). Here, we used 2-(nicotinamide)-1,3,4-thiadiazole (TGN-020), a potent selective inhibitor of aquaporin 4 (AQP4), to investigate the effects of TGN-020 on SCI in Sprague-Dawley rats. MAIN METHODS: We compressed the spinal cord at T10 using a sterile impounder (35 g, 5 min), to induce moderate injury. TGN-020 (100 mg/kg) or an equal volume of 10% dimethyl sulfoxide was then administered via intraperitoneal injection. Neurological function was evaluated using the Basso-Beattie-Bresnahan open-field locomotor scale 1, 3, 7, 14, 21, and 28 days after SCI. The degree of edema was assessed via determination of the precise spinal cord water content 3 days after SCI. Expression levels of AQP4, glial fibrillary acidic protein (GFAP), proliferating cell nuclear antigen (PCNA), and growth-associated protein-43 (GAP-43) were determined via western blotting and immunofluorescence staining 3 days after SCI and 4 weeks after SCI. Numbers of surviving neurons and glial scar sizes were determined using Nissl and hematoxylin-eosin staining, respectively. KEY FINDINGS: Our results showed that TGN-020 promoted functional recovery at days 3, 7, 14, 21, and 28, as well as reduced the degree of edema and inhibited the expression of AQP4, GFAP, PCNA at days 3 after SCI. Furthermore, observations 4 weeks after SCI revealed that TGN-020 inhibited the glial scar formation and upregulated GAP-43 expression. SIGNIFICANCE: TGN-020 can alleviate spinal cord edema, inhibit glial scar formation, and promote axonal regeneration, conferring beneficial effects on recovery in rats.
Authors: Kim Wagner; Lucas Unger; Mootaz M Salman; Philip Kitchen; Roslyn M Bill; Andrea J Yool Journal: Int J Mol Sci Date: 2022-01-26 Impact factor: 5.923