Cellular and Molecular Neurobiology

, Volume 32, Issue 6, pp 979–987 | Cite as

Protective Effect of Bacopa monniera on Methyl Mercury-Induced Oxidative Stress in Cerebellum of Rats

  • Thangarajan Sumathi
  • Chandrasekar Shobana
  • Johnson Christinal
  • Chandran Anusha
Original Research


Methyl mercury (MeHg) is a ubiquitous environmental pollutant leading to neurological and developmental deficits in animals and human beings. Bacopa monniera (BM) is a perennial herb and is used as a nerve tonic in Ayurveda, a traditional medicine system in India. The objective of the present study was to investigate whether Bacopa monniera extract (BME) could potentially inhibit MeHg-induced toxicity in the cerebellum of rat brain. Male Wistar rats were administered with MeHg orally at a dose of 5 mg/kg b.w. for 21 days. Experimental rats were given MeHg and also administered with BME (40 mg/kg, orally) for 21 days. After the treatment period, we observed that MeHg exposure significantly inhibited the activities of superoxide dismutase, catalase, glutathione peroxidase, and increased the glutathione reductase activity in cerebellum. It was also found that the level of thiobarbituric acid-reactive substances was increased with the concomitant decrease in the glutathione level in MeHg-induced rats. These alterations were prevented by the administration of BME. Behavioral interference in the MeHg-exposed animals was evident through a marked deficit in the motor performance in the rotarod task, which was completely recovered to control the levels by BME administration. The total mercury content in the cerebellum of MeHg-induced rats was also increased which was measured by atomic absorption spectrometry. The levels of NO2 and NO3 in the serum were found to be significantly increased in the MeHg-induced rats, whereas treatment with BME significantly decreased their levels in serum to near normal when compared to MeHg-induced rats. These findings strongly implicate that BM has potential to protect brain from oxidative damage resulting from MeHg-induced neurotoxicity in rat.


Methyl mercury Bacopamonniera Cerebellum Neuroprotection 



The work described in this article was supported by Department of Medical Biochemistry, DR. ALMPGIBMS, University of Madras, Taramani Campus, Chennai 113, Tamil Nadu, India.

Conflict of interest

The authors declare that there is no conflict of interests.


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Thangarajan Sumathi
    • 1
  • Chandrasekar Shobana
    • 1
  • Johnson Christinal
    • 1
  • Chandran Anusha
    • 1
  1. 1.Department of Medical BiochemistryDr. ALM Post Graduate Institute of Basic Medical Sciences, University of MadrasChennaiIndia

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