Korean Red Ginseng Extract Exhibits Neuroprotective Effects through Inhibition of Apoptotic Cell Death

Abstract

Red ginseng has long been used as a traditional medicine in many East Asian countries including Korea. It is known to exhibit various pharmacological effects, including anti-oxidant, anti-cancer, anti-stress and anti-diabetes activities. To further explore its actions, the present study evaluated effects of Korean red ginseng (KRG) extract on neuronal injury induced by various types of insults using primary cultured rat cortical cells. KRG extract inhibited neuronal damage and generation of intracellular reactive oxygen species (ROS) induced by excitatory amino acids, such as glutamate and N-methyl-D-aspartate (NMDA), or by A β(25-35) . To elucidate possible mechanism(s) by which KRG extract exerts neuroprotective action, its effects on apoptosis and apoptosis-related signaling molecules in neurons were assessed. KRG extract markedly increased phosphorylation of Bad at Ser 112 and inhibited Bax expression and caspase 3 activity. It also inhibited DNA fragmentation induced by NMDA or A β(25-35) . These results indicate that KRG extract protects cultured neurons from excitotoxicity and A β(25-35) -induced toxicity through inhibition of ROS generation and apoptotic cell death. In addition, KRG extract inhibited β-secretase activity, implying that it may reduce A β peptide formation. Taken together, these findings suggest that KRG extract may be beneficial for the prevention and/or treatment of neurodegenerative disorders including Alzheimer's disease.

Protection of Cultured Cortical Neurons by Luteolin against Oxidative Damage through Inhibition of Apoptosis and Induction of Heme Oxygenase-1

“…28) Briefly, the cells were washed with HCSS and exposed to 10 µM DCFH-DA in MEM for 30 min. Following this treatment, the cells were washed with HCSS and exposed to either 100 µM H 2 O 2 or X (0.5 mM)/XO (10 mU/mL) for 2 h in MEM in the absence or presence of various concentrations of luteolin.…”

“…For instance, luteolin was shown to exhibit neuroprotection against kainic acid-induced damage in rats and to improve learning and memory. 21) Using cultured cortical neuronal cells, it was reported that luteolin prevented amyloid β (A β ) (25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35) -induced neuronal cell death. 22) In a similar type of cultured cells treated with oxidative insult, luteolin was also found to markedly attenuate cytotoxicity and improve mitochondrial function as well as increase endogenous glutathione level and catalase activity.…”

Implications of red Panax ginseng in oxidative stress associated chronic diseases

“…Red ginseng water extract (0.3–3 mg/mL) blocked ROS generation and neuronal apoptosis, which was stimulated by glutamate, N -methyl- D -aspartate, or β-amyloid in rat cortical cells. These results implied the potential of red ginseng to aid in the prevention of neuronal diseases [29]. Additionally, red ginseng extract (0.01–1 mg/mL; major constituents: Rb1, Rb2, Rc, Rd, Re, Rf, Rg1, and Rg3) was reported to have a neuroprotective effect on primary rat hippocampal neurons, where toxicity was induced by kainite, a glutamate analogue [30].…”

Neuroprotective effect of Korea Red Ginseng extract on 1-methyl-4-phenylpyridinium-induced apoptosis in PC12 Cells

“…Ginsenoside Rg2 reduced glutamate-induced cell death significantly through mechanisms related to anti-apoptosis and anti-oxidation in PC12 cells (Li et al 2007). A few studies also reported that the water extract of KRG protected cultured cortical cells from amyloid-β-induced apoptosis (Kim et al 2014) and repressed apoptosis in SK-N-SH cells by suppressing oxidative stress (Nguyen et al 2015). Therefore, the ginsenosides may play an important role in the observed prevention of apoptotic cell death in response to the KRG extract, but the possibility that other substances are involved in the anti-apoptotic effect still remains.…”