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Yuen, C.-W.

Publications and source records attributed to Yuen, C.-W..

2 recordsLinked to original sources

Tocotrienol decreases β-amyloid mediated toxicity in Caenorhabditis elegans model of Alzheimer's disease

Alzheimers disease (AD) is a neurological disease caused by the accumulation of extracellular senile plaques consisting of {beta}-amyloid peptide (A{beta}) in the brain. A transgenic Caenorhabditis elegans which demonstrated paralysis due to the expression of human beta amyloid A{beta}42 gene was used to study the anti-paralysis effect of mixed tocotrienols. The content of the mixed tocotrienols were 12.1% -, 2.7% {beta}-, 18.6% {gamma}-, and 8.1% {delta}-tocotrienols. Mixed tocotrienols significantly delayed the A{beta}-induced paralysis in the transgenic nematode and exhibited anti-oxidant properties towards A{beta}-generated oxidative stress. The mixture also presented potent inhibitory activities against A{beta} aggregation with an IC50 value of 600 ng/ml. It is concluded that mixed tocotrienols could potentially serve as a new therapeutic candidate for AD.

pharmacology and toxicology

Effects of salvianolic acid A on β-amyloid mediated toxicity in Caenorhabditis elegans model of Alzheimer's disease

Alzheimers disease (AD) is a brain disease attributed to the accumulation of extracellular senile plaques comprising {beta}-amyloid peptide (A{beta}). In this study, a transgenic Caenorhabditis elegans containing the human beta amyloid A{beta}42 gene which exhibited paralysis when expressed, was used to study the anti-paralysis effect of salvianolic acid A. Various concentrations ranging from 1 g/ml to 100 g/ml of salvianolic acid A were tested and exhibited the highest effect on the worm at the concentration of 100 g/ml. For anti-aggregation effect, 14 g/ml salvianolic acid A (within 4 mg/ml of Danshen) showed a significant level of inhibition of the formation of A{beta} fibrils. An amount of 100 g/ml of salvianolic acid A had the potential in reducing the ROS but did not totally obliterate the ROS production in the worms. Salvianolic acid A was found to delay the paralysis of the transgenic C. elegans, decrease A{beta}42 aggregation and decreased A{beta}-induced oxidative stress.

pharmacology and toxicology