NMDA Receptor-Mediated Neuroprotective Effect of theScutellaria baicalensisGeorgi Extract on the Excitotoxic Neuronal Cell Death in Primary Rat Cortical Cell Cultures

Abstract

The objective of the current research work was to evaluate the neuroprotective effect of the ethanol extract of Scutellaria baicalensis (S.B.) on the excitotoxic neuronal cell death in primary rat cortical cell cultures. The inhibitory effects of the extract were qualitatively and quantitatively estimated by phase-contrast microscopy and lactate dehydrogenase (LDH) assays. The extract exhibited a potent and dose-dependent inhibition of the glutamate-induced excitotoxicity in the culture media. Further, using radioligand binding assays, it was observed that the inhibitory effect of the extract was more potent and selective for the N-methyl-D-aspartate (NMDA) receptor-mediated toxicity. The S.B. ethanol extract competed with [3H] MDL 105,519 for the specific binding to the NMDA receptor glycine site with 50% inhibition occurring at 35.1 μg/mL. Further, NMDA receptor inactivation by the S.B. ethanol extract was concluded from the decreasing binding capability of [3H]MK-801 in the presence of the extract. Thus, S.B. extract exhibited neuroprotection against excitotoxic cell death, and this neuroprotection was mediated through the inhibition of NMDA receptor function by interacting with the glycine binding site of the NMDA receptor. Phytochemical analysis of the bioactive extract revealed the presence of six phytochemical constituents including baicalein, baicalin, wogonin, wogonoside, scutellarin, and Oroxylin A.

[Retracted] Natural Products for Neurodegeneration: Regulating Neurotrophic Signals

“…The ethanol extract of Scutellaria baicalensis Georgi. protects cell cultures of primary rat cortical neurons against glutamate toxicity by binding with the glycine-binding site of the N-methyl-D-aspartate receptor [ 83 ]. Estrogen and insulin-like growth factor-1 (IGF-1) receptors facilitate NTF stimulation and neuronal protection by various flavonoids (i.e., calycosin, luteolin, ginsenoside Rg1, genistein) in the PD rat model [ 84 , 85 ].…”

A comprehensive review on phytochemistry, pharmacology, and flavonoid biosynthesis ofScutellaria baicalensis

“…The extact could also protect animals from global cerebral ischemia and MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-induced Parkinson's disease, and protect cortical and neuronal cells from glutamate, NMDA ( N -methyl-D-aspartic acid), and H 2 O 2 induced toxicity in vitro (Yang et al. 2014; Cao et al. 2016; Li et al.…”

Therapeutic Potential of Baicalein in Alzheimer’s Disease and Parkinson’s Disease

“…In rat primary mesencephalic cultures, baicalein inhibited the glutamate -induced intracellular calcium ion increase. Baicalein also showed neuroprotective effects on excitotoxic neuronal cell death in primary rat cortical cell cultures (Yang et al, 2014). Interestingly, an improved drugs screening system revealed that baicalein not only ameliorates the Aβ-induced depolarization of neurons, but also possibly functions as an antagonist of AMPA and NMDA receptors (Lin et al, 2017).…”