Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra compacta.Ferroptosis,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidati...Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra compacta.Ferroptosis,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic neurons.However,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely elucidated.NADPH oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains unknown.The aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what mechanism.We found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease model.NADPH oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic neurons.Moreover,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model animals.Mechanistically,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic neurons.Furthermore,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced neuroinflammation.These findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.展开更多
Objective: To evaluate the antioxidation of dihydrobiopterin reductase and to explore the effect of A278C mutation of the quinoid dihydropteridine reductase(QDPR) gene on its antioxidant activity. Methods: First, plas...Objective: To evaluate the antioxidation of dihydrobiopterin reductase and to explore the effect of A278C mutation of the quinoid dihydropteridine reductase(QDPR) gene on its antioxidant activity. Methods: First, plasmids with different genes(wild and mutant QDPR) were constructed. After gene sequencing, they were transfected into human kidney cells(HEK293T). Then, the intracellular production of reactive oxygen species(ROS) and tetrahydrobiopterin(BH4) was detected after cells were harvested. Activations of nicotinamide adenine dinucleotide phosphate oxidase 4(NOX4), glutathione peroxidase 3(GPX3), and superoxide dismutase 1(SOD1) were analyzed to observe the oxidative stress after transfection. The expression of the neuronal nitric oxide synthase(n NOS) gene was analyzed by semiquantitative reverse-transcription polymerase chain reaction(RT-PCR). We also detected the activation of transforming growth factor β1(TGF-β1) by enzyme-linked immunosorbent assay(ELISA) to observe the connection of TGF-β1 and oxidative stress. Results: The exogenous wild-type QDPR significantly decreased the expression of n NOS, NOX4, and TGF-β1 and induced the expression of SOD1 and GPX3, but the mutated QDPR lost this function and resulted in excessive ROS production. Our data also suggested that the influence on the level of BH4 had no significant difference between mutated and the wild-type QDPR transfection. Conclusions: Wild-type QDPR played an important role in protecting against oxidative stress, but mutant QDPR failed to have these beneficial effects.展开更多
基金supported by the National Natural Science Foundation of China,Nos.82271444(to JP),82271268(to BZ),and 82001346(to YL)the National Key Research and Development Program of China,No.2022YFE0210100(to BZ)。
文摘Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra compacta.Ferroptosis,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic neurons.However,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely elucidated.NADPH oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains unknown.The aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what mechanism.We found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease model.NADPH oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic neurons.Moreover,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model animals.Mechanistically,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic neurons.Furthermore,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced neuroinflammation.These findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.
基金supported by the National Natural Science Foundation of China(No.81130066)the International Cooperation and Exchanges of the National Natural Science Foundation of China(No.81620108031)
文摘Objective: To evaluate the antioxidation of dihydrobiopterin reductase and to explore the effect of A278C mutation of the quinoid dihydropteridine reductase(QDPR) gene on its antioxidant activity. Methods: First, plasmids with different genes(wild and mutant QDPR) were constructed. After gene sequencing, they were transfected into human kidney cells(HEK293T). Then, the intracellular production of reactive oxygen species(ROS) and tetrahydrobiopterin(BH4) was detected after cells were harvested. Activations of nicotinamide adenine dinucleotide phosphate oxidase 4(NOX4), glutathione peroxidase 3(GPX3), and superoxide dismutase 1(SOD1) were analyzed to observe the oxidative stress after transfection. The expression of the neuronal nitric oxide synthase(n NOS) gene was analyzed by semiquantitative reverse-transcription polymerase chain reaction(RT-PCR). We also detected the activation of transforming growth factor β1(TGF-β1) by enzyme-linked immunosorbent assay(ELISA) to observe the connection of TGF-β1 and oxidative stress. Results: The exogenous wild-type QDPR significantly decreased the expression of n NOS, NOX4, and TGF-β1 and induced the expression of SOD1 and GPX3, but the mutated QDPR lost this function and resulted in excessive ROS production. Our data also suggested that the influence on the level of BH4 had no significant difference between mutated and the wild-type QDPR transfection. Conclusions: Wild-type QDPR played an important role in protecting against oxidative stress, but mutant QDPR failed to have these beneficial effects.
