title: Neuroprotection by urate on 6-OHDA-lesioned rat model of Parkinson's disease: linking to Akt/GSK3β signaling pathway.
abstract: Higher plasma urate level is reported to be associated with a reduced risk and slower progression of Parkinson's disease (PD). In this study, we explored the effects of urate on dopaminergic neurons in nigrostriatal pathway in the 6-hydroxydopamine (6-OHDA) unilaterally lesioned rats. Uric acid (UA), when given twice daily at 200 mg/kg intraperitoneally for 10 consecutive days, elevated urate (the anionic form of UA) in plasma and striatum by 55% and 36.8%, respectively, as compared with vehicle group. This regimen of UA was found to ameliorate the behavioral deficits, dopaminergic neuron loss as well as dopamine depletion in the nigrostriatal system. Moreover, UA administration was capable of increasing glutathione level and superoxide dismutase activity while decreasing malondialdehyde accumulation in striatum. In addition, the phosphorylation of both protein kinase B (Akt) and glycogen synthase kinase 3 beta (GSK3β) in the lesioned striata of 6-OHDA-lesioned rats was dramatically reduced as compared with sham-operated rats. This reduction was attenuated in the Parkinsonian rats receiving UA treatment. Similarly, in vitro findings showed that UA alleviated the decrease in Akt activation and the increase in GSK3β activity caused by 6-OHDA. Furthermore, neuroprotection by urate and its regulation on GSK3β phosphorylation at Ser9 was found to be abolished in the presence of PI3K inhibitor. Therefore, our findings demonstrated that urate was able to protect dopaminergic neurons in rat nigrostriatal pathway against the neurotoxicity of 6-OHDA, and showed that its beneficial effects may be related to its regulation on Akt/GSK3β signaling.
authors.affiliation: Department of Neurology, The Second Affiliated Hospital of Soochow University, Suzhou, China.
authors.forename: Li
authors.initials: L
authors.lastname: Gong
authors.forename: Qi-Lin
authors.initials: QL
authors.lastname: Zhang
authors.forename: Ning
authors.initials: N
authors.lastname: Zhang
authors.forename: Wen-Yan
authors.initials: WY
authors.lastname: Hua
authors.forename: Yi-Xian
authors.initials: YX
authors.lastname: Huang
authors.forename: Ping-Wei
authors.initials: PW
authors.lastname: Di
authors.forename: Tingting
authors.initials: T
authors.lastname: Huang
authors.forename: Xing-Shun
authors.initials: XS
authors.lastname: Xu
authors.forename: Chun-Feng
authors.initials: CF
authors.lastname: Liu
authors.forename: Li-Fang
authors.initials: LF
authors.lastname: Hu
authors.forename: Wei-Feng
authors.initials: WF
authors.lastname: Luo
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D059290:Dopaminergic Neurons / Q000187:drug effects / Q000378:metabolism; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism*; D000071679:Glycogen Synthase Kinase 3 beta; D007150:Immunohistochemistry; D008297:Male; D018696:Neuroprotective Agents / Q000378:metabolism / Q000494:pharmacology*; D020734:Parkinsonian Disorders / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects*; D014527:Uric Acid / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D018696:Neuroprotective Agents; D014527:Uric Acid; D000071679:Glycogen Synthase Kinase 3 beta; C000605508:Gsk3b protein, rat; D051057:Proto-Oncogene Proteins c-akt; D038362:Glycogen Synthase Kinase 3