1: Pharmacol Biochem Behav. 2006 Jan;83(1):150-60. Epub 2006 Feb 28.
Attenuation by Nardostachys jatamansi of 6-hydroxydopamine-induced parkinsonism
in rats: behavioral, neurochemical, and immunohistochemical studies.
Ahmad M, Yousuf S, Khan MB, Hoda MN, Ahmad AS, Ansari MA, Ishrat T, Agrawal AK,
Islam F.
Neurotoxicology Laboratory, Department of Medical Elementology and Toxicology,
Jamia Hamdard (Hamdard University), Hamdard Nagar, New Delhi 110062, India.
mahmad7@jhmi.edu
Parkinson's disease (PD) is one of the commonest neurodegenerative diseases, and
oxidative stress has been evidenced to play a vital role in its causation. In
the present study, we evaluated whether ethanolic extract of Nardostachys
jatamansi roots (ENj), an antioxidant and enhancer of biogenic amines, can slow
the neuronal injury in a 6-OHDA-rat model of Parkinson's. Rats were treated with
200, 400, and 600 mg/kg body weight of ENj for 3 weeks. On day 21, 2 microl of
6-OHDA (12 microg in 0.01% in ascorbic acid-saline) was infused into the right
striatum, while the sham-operated group received 2 microl of vehicle. Three
weeks after the 6-OHDA injection, the rats were tested for neurobehavioural
activity and were sacrificed after 6 weeks for the estimation of lipid
peroxidation, reduced glutathione content, the activities of
glutathione-S-transferase, glutathione reductase, glutathione peroxidase,
superoxide dismutase and catalase, quantification of catecholamines,
dopaminergic D2 receptor binding and tyrosine hydroxylase expression. The
increase in drug-induced rotations and deficits in locomotor activity and
muscular coordination due to 6-OHDA injections were significantly and
dose-dependently restored by ENj. Lesioning was followed by an increased lipid
peroxidation and significant depletion of reduced glutathione content in the
substantia nigra, which was prevented with ENj pretreatment. The activities of
glutathione-dependent enzymes, catalase and superoxide dismutase in striatum,
which were reduced significantly by lesioning, were dose-dependently restored by
ENj. A significant decrease in the level of dopamine and its metabolites and an
increase in the number of dopaminergic D2 receptors in striatum were observed
after 6-OHDA injection, and both were significantly recovered following ENj
treatment. All of these results were exhibited by an increased density of
tyrosine hydroxylase immunoreactive (TH-IR) fibers in the ipsilateral striatum
of the lesioned rats following treatment with ENj; 6-OHDA injection had induced
almost a complete loss of TH-IR fibers. This study indicates that the extract of
Jatamansi might be helpful in attenuating Parkinsonism.
PMID: 16500697 [PubMed - indexed for MEDLINE]