Open Access Highly Accessed Open Badges Research article

Paraquat induces oxidative stress, neuronal loss in substantia nigra region and Parkinsonism in adult rats: Neuroprotection and amelioration of symptoms by water-soluble formulation of Coenzyme Q10

Mallika Somayajulu-Niţu1, Jagdeep K Sandhu3, Jerome Cohen2, Marianna Sikorska3, TS Sridhar14, Anca Matei2, Henryk Borowy-Borowski3 and Siyaram Pandey1*

Author Affiliations

1 Chemistry & Biochemistry, University of Windsor, Windsor, ON, Canada

2 Psychology, University of Windsor, Windsor, ON, Canada

3 Institute for Biological Sciences, National Research Council Canada, Ottawa, ON, Canada

4 St John's Research Institute, Bangalore, India

For all author emails, please log on.

BMC Neuroscience 2009, 10:88  doi:10.1186/1471-2202-10-88

Published: 27 July 2009



Parkinson's disease, for which currently there is no cure, develops as a result of progressive loss of dopamine neurons in the brain; thus, identification of any potential therapeutic intervention for disease management is of a great importance.


Here we report that prophylactic application of water-soluble formulation of coenzyme Q10 could effectively offset the effects of environmental neurotoxin paraquat, believed to be a contributing factor in the development of familial PD. In this study we utilized a model of paraquat-induced dopaminergic neurodegeneration in adult rats that received three weekly intra-peritoneal injections of the herbicide paraquat. Histological and biochemical analyses of rat brains revealed increased levels of oxidative stress markers and a loss of approximately 65% of dopamine neurons in the substantia nigra region. The paraquat-exposed rats also displayed impaired balancing skills on a slowly rotating drum (rotorod) evidenced by their reduced spontaneity in gait performance. In contrast, paraquat exposed rats receiving a water-soluble formulation of coenzyme Q10 in their drinking water prior to and during the paraquat treatment neither developed neurodegeneration nor reduced rotorod performance and were indistinguishable from the control paraquat-untreated rats.


Our data confirmed that paraquat-induced neurotoxicity represents a convenient rat model of Parkinsonian neurodegeneration suitable for mechanistic and neuroprotective studies. This is the first preclinical evaluation of a water-soluble coenzyme Q10 formulation showing the evidence of prophylactic neuroprotection at clinically relevant doses.