Molecular Neurobiology

, Volume 49, Issue 3, pp 1153–1165 | Cite as

Role and Mechanism of Microglial Activation in Iron-Induced Selective and Progressive Dopaminergic Neurodegeneration

  • Wei ZhangEmail author
  • Zhao-fen Yan
  • Jun-hua Gao
  • Li Sun
  • Xi-yan Huang
  • Zhuo Liu
  • Shu-yang Yu
  • Chen-Jie Cao
  • Li-jun Zuo
  • Ze-Jie Chen
  • Yang Hu
  • Fang Wang
  • Jau-shyong Hong
  • Xiao-min Wang


Parkinson’s disease (PD) patients have excessive iron depositions in substantia nigra (SN). Neuroinflammation characterized by microglial activation is pivotal for dopaminergic neurodegeneration in PD. However, the role and mechanism of microglial activation in iron-induced dopaminergic neurodegeneration in SN remain unclear yet. This study aimed to investigate the role and mechanism of microglial β-nicotinamide adenine dinucleotide phosphate oxidase 2 (NOX2) activation in iron-induced selective and progressive dopaminergic neurodegeneration. Multiple primary midbrain cultures from rat, NOX2+/+ and NOX2−/− mice were used. Dopaminergic neurons, total neurons, and microglia were visualized by immunostainings. Cell viability was measured by MTT assay. Superoxide (O2 ·−) and intracellular reactive oxygen species (iROS) were determined by measuring SOD-inhibitable reduction of tetrazolium salt WST-1 and DCFH-DA assay. mRNA and protein were detected by real-time PCR and Western blot. Iron induces selective and progressive dopaminergic neurotoxicity in rat neuron–microglia–astroglia cultures and microglial activation potentiates the neurotoxicity. Activated microglia produce a magnitude of O2 ·− and iROS, and display morphological alteration. NOX2 inhibitor diphenylene iodonium protects against iron-elicited dopaminergic neurotoxicity through decreasing microglial O2 ·− generation, and NOX2−/− mice are resistant to the neurotoxicity by reducing microglial O2 ·− production, indicating that iron-elicited dopaminergic neurotoxicity is dependent of NOX2, a O2 ·−-generating enzyme. NOX2 activation is indicated by the increased mRNA and protein levels of subunits P47 and gp91. Molecules relevant to NOX2 activation include PKC-σ, P38, ERK1/2, JNK, and NF-КBP65 as their mRNA and protein levels are enhanced by NOX2 activation. Iron causes selective and progressive dopaminergic neurodegeneration, and microglial NOX2 activation potentiates the neurotoxicity. PKC-σ, P38, ERK1/2, JNK, and NF-КBP65 are the potential molecules relevant to microglial NOX2 activation.


Dopaminergic neurodegeneration Iron Microglial activation Neuroinflammation β-nicotinamide adenine dinucleotide phosphate oxidase 2 Parkinson’s disease Mechanism 



This work is supported by the National Basic Research Program of China (2011CB504100); the National Natural Science Foundation of China (81071015, 30770745, and 81030062), the Natural Science Foundation of Beijing, China (7082032), High Level Technical Personnel Training Project of Beijing Health System, China (2009-3-26), Excellent Personnel Training Project of Beijing, China (20071D0300400076), Capital Clinical Characteristic Application Research (Z121107001012161), Important National Science and Technology Specific Projects ( 2011ZX09102-003-01), Key Project of Beijing Natural Science Foundation (kz200910025001), and Basic-Clinical Research Cooperation Funding of Capital Medical University (10JL49). We thank Dr. Yang Du for her efforts of editing the manuscript.

Supplementary material

12035_2013_8586_MOESM1_ESM.doc (58 kb)
ESM 1 (DOC 57.5 KB)


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Wei Zhang
    • 1
    • 2
    • 3
    Email author
  • Zhao-fen Yan
    • 1
  • Jun-hua Gao
    • 1
  • Li Sun
    • 1
  • Xi-yan Huang
    • 1
  • Zhuo Liu
    • 1
  • Shu-yang Yu
    • 1
  • Chen-Jie Cao
    • 1
  • Li-jun Zuo
    • 1
  • Ze-Jie Chen
    • 1
  • Yang Hu
    • 1
  • Fang Wang
    • 1
  • Jau-shyong Hong
    • 4
  • Xiao-min Wang
    • 5
    • 6
    • 7
    • 8
  1. 1.Department of Neurology, Beijing Tiantan HospitalCapital Medical UniversityBeijingChina
  2. 2.Parkinson’s Disease Center of Beijing Institute of Brain DisordersBeijingChina
  3. 3.Beijing Key Laboratory on Parkinson’s DiseaseBeijingChina
  4. 4.Neuropharmacology Section, Laboratory of Pharmacology and ChemistryNational Institute of Environmental Health Sciences/National Institutes of HealthNorth Carolina USA
  5. 5.Department of PhysiologyCapital Medical UniversityBeijingChina
  6. 6.Department of NeurobiologyCapital Medical UniversityBeijingChina
  7. 7.Key Laboratory for Neurodegenerative Disorders of the Ministry of EducationBeijingChina
  8. 8.Beijing Institute for Brain DisordersBeijingChina

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