Neuroprotective effect of Tagara, an Ayurvedic drug against methyl mercury induced oxidative stress using rat brain mitochondrial fractions

BMC Complementary and Alternative Medicine

Kalaivani Thiagarajan¹  Rajasekaran Chandrasekaran¹  Dhanoop Manikoth Ayyathan¹ 

[1] School of Biosciences and Technology, VIT University, Tamilnadu, India

关键词: Neuroprotection;    Mitochondrial viability;    Tagara;    Oxidative stress;    Methyl mercury;   

Others  :  1222571
DOI  :  10.1186/s12906-015-0793-2

 received in 2014-06-26, accepted in 2015-07-22,  发布年份 2015

【 摘 要 】

Background

Methyl mercury (MeHg), an important environmental toxicant is implicated in neurological disorders such as Hunter-Russell syndrome and Autism. Therefore, the present work is in search of new drugs that can alleviate MeHg toxicity. In this connection, Tagara, an ayurvedic drug is used for assessing its neuro protective effect against MeHg toxicity.

Methods

In the present study, we assessed the phytochemical contents of Tagara by colorimetric and HPLC analyses. The neuroprotective effect of Tagara on MeHg induced neurotoxicity was measured in terms of viability by MTT assay and oxidative stress in terms of catalase activity, glutathione and thiobarbituric acid reactive substance levels. Further, the chelating effect of Tagara towards MeHg was performed to identify the molecular mechanism. Statistical analysis was done by statistical package for social sciences (SPSS) version 16.0.

Results

The results demonstrated that Tagara contains significant amounts of phenols and flavonoids. Also, HPLC analysis of Tagara revealed the presence of essential oils such as hydroxyvalerenic and valerenic acids. Our results demonstrated that exposure of rat brain mitochondrial fractions to MeHg resulted in a dose dependent death in MTT assay and IC ₅₀value was found to be 10 μM. However, a 250 μg dose of Tagara effectively prevented MeHg induced mitochondrial damage. The oxidative stress caused by MeHg results in elevated levels of reactive oxygen species as evidenced by elevated TBARS (Thiobarbituric acid-reactive substances) levels and diminished catalase enzyme activity and glutathione content. However, Tagara at 250 μg concentration offsets these alterations caused by MeHg. Further, Tagara also diminished GSH oxidation caused by MeHg, confirming its chelating effect, one of the molecular mechanisms that triggers protection against oxidative damage.

Conclusion

Our results revealed that MeHg induced toxicity is predominantly mediated through oxidative stress mechanism and the propensity of Tagara to abolish such reactions. Hence, we propose that Tagara with a source of potential neuroprotectants may be a useful approach to alleviate MeHg associated neurotoxicity.

【 授权许可】

   
2015 Ayyathan et al.

【 图 表 】

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