• Journal of Ginseng Research
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• v.34 no.3
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• pp.246-253
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• 2010

Ginsenoside $Rg_3$ ($Rg_3$), one of the active ingredients in Panax ginseng, attenuates NMDA receptor-mediated currents in vitro and antagonizes NMDA receptors through a glycine modulatory site in rat cultured hippocampal neurons. In the present study, we examined the neuroprotective effects of $Rg_3$ on 24-hydroxycholesterol (24-OH-chol)-induced cytotoxicity in vitro. The results showed that $Rg_3$ treatment significantly and dose-dependently inhibited 24-OH-chol-induced cell death in rat cultured cortical neurons, with an $IC_{50}$ value of $28.7{\pm}7.5\;{\mu}m$. Furthermore, the $Rg_3$ treatment not only significantly reduced DNA damage, but also dose-dependently attenuated 24-OH-chol-induced caspase-3 activity. To study the mechanisms underlying the in vitro neuroprotective effects of $Rg_3$ against 25-OH-chol-induced cytotoxicity, we also examined the effect of $Rg_3$ on intracellular $Ca^{2+}$ elevations in cultured neurons and found that $Rg_3$ treatment dose-dependently inhibited increases in intracellular $Ca^{2+}$, with an $IC_{50}$ value of $40.37{\pm}12.88\;{\mu}m$. Additionally, $Rg_3$ treatment dose-dependently inhibited apoptosis with an $IC_{50}$ of $47.3{\pm}14.2\;{\mu}m$. Finally, after confirming the protective effect of $Rg_3$ using a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay, we found that $Rg_3$ is an active component in ginseng-mediated neuroprotection. These results collectively indicate that $Rg_3$-induced neuroprotection against 24-OH-chol in rat cortical neurons might be achieved via inhibition of a 24-OH-chol-mediated $Ca^{2+}$ channel. This is the first report to employ cortical neurons to study the neuroprotective effects of $Rg_3$ against 24-OH-chol. In conclusion, $Rg_3$ was effective for protecting cells against 24-OH-chol-induced cytotoxicity in rat cortical neurons. This protective ability makes $Rg_3$ a promising agent in pathologies implicating neurodegeneration such as apoptosis or neuronal cell death.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.9
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• pp.1131-1138
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• 2009

In this study, the breads with medicinal herbs (MH) composites showing cognitive function were prepared and their characteristics were examined. Fifteen kinds of medicinal herbs were extracted with hot water and divided into 3 groups (MH-1, MH-2, MH-3) based on their contents. All groups showed cognitive function in terms of promoting muscarinic receptor, NMDA receptor and acetylcholinesterase inhibition. In the preparation of breads containing MH extracts of various contents (0, 10, 20, 30, and 50%), there were no significant difference among loaf weight of all groups, but loaf volume of all groups were significantly (p<0.05) decreased with increasing content of MH extracts compared to the control group. The "a" and "b" values of bread crumb increased with the content of MH extracts while "L" value decreased, but these values of bread crust were similar to the control group. The most improvements in hardness, fracturability, cohesiveness, gumminess and chewiness of bread were noticed by the addition of 10$\sim$20% MH extracts, while adhesiveness and springiness of bread were the most by the 30% addition ones. Through the sensory evaluation, it was revealed that appearance, mouth feeling, taste, overall preference and crumb texture of bread were not significantly different (p<0.05) between control and those with the 10% addition ones. Therefore the 10% addition ones, which got similar scores to control, will make the most desirable product.