Pretreatment with Rhodiola rosea extract reduces cognitive impairment induced by intracerebroventricular streptozotocin in rats: implication of anti-oxidative and neuroprotective effects.
OBJECTIVE
To investigate the pretreatment effects of Rhodiola rosea (R. rosea) extract on cognitive dysfunction, oxidative stress in hippocampus and hippocampal neuron injury in a rat model of Alzheimer's disease (AD).


METHODS
Male Sprague-Dawley rats were pretreated with R. rosea extract at doses of 1.5, 3.0, and 6.0 g/kg for 3 weeks, followed by bilateral intracerebroventricular injection with streptozotocin (1.5 mg/kg) on days 1 and 3. Behavioral alterations were monitored after 2 weeks from the lesion using Morris water maze task. Three weeks after the lesion, the rats were sacrificed for measuring the malondialdehyde (MDA), glutathione reductase (GR) and reduced glutathione (GSH) levels in hippocampus and histopathology of hippocampal neurons.


RESULTS
The MDA level was significantly increased while the GR and GSH levels were significantly decreased with striking impairments in spatial learning and memory and severe damage to hippocampal neurons in the model rat induced by intracerebroventricular injection of streptozotocin. These abnormalities were significantly improved by pretreatment with R. rosea extract (3.0 g/kg).


CONCLUSIONS
R. rosea extract can protect rats against cognitive deficits, neuronal injury and oxidative stress induced by intracerebroventricular injection of streptozotocin, and may be used as a potential agent in treatment of neurodegenerative diseases such as AD.
Qu
Ze-Qiang
ZQ
Division of Neuroscience, Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou 510080, Guangdong, China.
Zhou
Yan
Y
Zeng
Yuan-Shan
YS
Li
Yan
Y
Chung
Peter
P
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D015415:Biomarkers / Q000378:metabolism; D002452:Cell Count; D003072:Cognition Disorders / Q000139:chemically induced / Q000188:drug therapy* / Q000503:physiopathology; D006624:Hippocampus / Q000187:drug effects / Q000473:pathology; D007276:Injections, Intraventricular; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000473:pathology; D018696:Neuroprotective Agents / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D029771:Rhodiola / Q000378:metabolism*; D013311:Streptozocin / Q000008:administration & dosage; D013550:Swimming / Q000502:physiology
D015415:Biomarkers; D018696:Neuroprotective Agents; D010936:Plant Extracts; D013311:Streptozocin