<i>In vitro</i> evaluation of antiproliferative effect of ethyl gallate against human oral squamous carcinoma cell line KB

<div><p>Although some polyphenols are known to possess anticancer activity against different cancer cell lines through induction of apoptosis, the mode of antiproliferative effect of ethyl gallate against human oral squamous carcinoma cell line KB was not studied until now. Therefore, the antiproliferative effect of ethyl gallate was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay in comparison with the reference drug paclitaxel. Generation of reactive oxygen species, mitochondrial membrane potential loss, DNA damage and apoptosis were determined using 2,7-diacetyldichlorofluorescein fluorescence, uptake of rhodamine-123 by mitochondria, comet assay and acridine orange/ethidium bromide dual-dye staining method. Both ethyl gallate and paclitaxel exhibited cytotoxicity in a dose-dependent manner. The 50% inhibitory concentration for ethyl gallate was 30 and 20 μg/mL for paclitaxel. A volume of 50 μg/mL of ethyl gallate was found to be significantly effective (<i>P</i> < 0.05) in controlling the cancer cell proliferation leading to acute apoptosis.</p></div

Neuroprotective effect of Brahmi, an ayurvedic drug against oxidative stress induced by methyl mercury toxicity in rat brain mitochondrial-enriched fractions

<div><p>The present study evaluates the neuroprotective effect of Brahmi against methyl mercury (MeHg) toxicity. The results demonstrated that MeHg-decreased mitochondrial viability in MTT assay and IC₅₀ value was found to be 2.5 μg/mL. However, Brahmi at 250 μg/mL concentration effectively prevented mitochondrial damage caused by MeHg in MTT assay. Our results also demonstrated MeHg significantly inhibited catalase enzyme activity, glutathione content and increased the level of thiobarbituric acid reactive substances in mitochondrial-enriched fractions of rat brain. These alterations were prevented by preincubation with Brahmi. In addition, Brahmi reverted glutathione level to normal that was depleted by MeHg, confirming its chelating effect, one of the molecular mechanisms that underlie protection against oxidative damage. Our study also focused on total phenolic and flavonoid contents of Brahmi, and it was found to contain significant amount of phenols and flavonoids. The presence of saponins was detected by HPLC which might be responsible for neuroprotection against MeHg.</p></div