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OBJECTIVE Amyotrophic lateral sclerosis(ALS)is a fetal neurodegenerative disease characterized by the progressive loss of upper and lower motor neu-rons,leading to skeletal muscle atrophy,weakness,and paralysis.Oxidative stress plays a crucial role in ALS pathogenesis,including the familial forms of the disease arising from mutations in the gene coding for superox-ide dismutase(SOD1).Additionally,the abnormal accu-mulation of TAR DNA-binding protein of 43 ku(TDP-43)is a pathological feature present in almost all patients,even though the pathogenesis of ALS is unclear.Current-ly,there is no drug that can cure ALS/FTLD.Tetramethyl-pyrazine nitrone(TBN)is a derivative of tetramethylapyr-azine,derived from traditional Chinese medicine Ligusti-cum chuanxiong,which has been extensively proven to have therapeutic effects on various models of neurode-generative diseases.METHODS We investigated the therapeutic effect of TBN in the SOD1G93A and TDP-43M337V ALS mouse models.In the SOD1G93A trans-genic mouse model,TBN was administered to mice via intraperitoneal or intragastric injection after the onset of motor deficits.We injected the TDP-43M337V virus into the striatum of mice unilaterally and bilaterally,and then administered TBN 30 mg·kg-1 intragastrically to observe changes in behavior and survival rate of mice.RESULTS TBN slowed the progression of motor neuron disease,as evidenced by improved motor performance,reduced spi-nal motor neuron loss and associated glial response,and decreased skeletal muscle fiber denervation and fibrosis.TBN treatment activated mitochondrial antioxidant activity through the PGC-1α/Nrf2/HO-1 pathway and decreased the expression of human SOD1.In the mice with unilateral injection of TDP-43M337V into the striatum,TBN improved motor deficits and cognitive impairment in the early stages of disease progression.In mice with bilateral injection of TDP-43M337V into the striatum,TBN not only improved motor function but also prolonged survival.Moreover,we demonstrate that its therapeutic effect may be through activation of the Akt/mTOR/GSK-3β and AMPK/PGC-1α/Nrf2 signaling pathways.CONCLUSION TBN shows promise as an agent for the treatment of ALS/FTLD.TBN is currently undergoing clinical investigation for several indications,including a Phase Ⅱ trial for ALS.
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OBJECTIVES@#To investigate the role of tetramethylpyrazine(TMP) nitrone in proliferation and differentiation of neural stem cells (NSCs).@*METHODS@#We separated and cultivated the original generation of NSCs from cerebral cortex of 14 days rat embryo, and the phenotype characteristics of the third-generation NSCs was tested by immunofluorescence. The experiment was divided into control group, β-mercaptoethanol positive control group, tetramethylpyrazine nitrone group and tetramethylpyrazine nitrone + ethylene glycol tetraacetic acid(EGTA) group (=4). The third-generation cultivation of NSCs was used in the experiment. The effect of tetramethylpyrazine nitrone on the number of NSCs proliferation was determined by BrdU and MTT, and the differentiation of NSCs was determined by Western blot.@*RESULTS@#The primary NSCs was isolated successfully, neurospheres with typical NSCs morphology and expressing nestin was formed at 3-5 days. As BrdU and MTT assay results shown, compared with the control group andβ-mercaptoethanol positive control group, the NSCs proliferation numbers of tetramethylpyrazine nitrone group increased significantly(<0.05). The results of Western blot showed that the neuronal differentiation rate of NSCs was increased significantly in both the tetramethylpyrazine nitrone group and tetramethylpyrazine nitrone + EGTA group, and the differentiation rate of NSCs in tetramethylpyrazine nitrone + EGTA group increased more significantly(<0.05).@*CONCLUSIONS@#Tetramethylpyrazine nitrone can significantly enhance the proliferation and neuronal differentiation rate of NSCs. Decrease in extracellular Ca can promote the differentiation of NSCs into neurons induced by tetramethylpyrazine nitrone. Ca signaling plays an important role in the differentiation of NSCs into neurons.