Gastrodia elataBL Mediates the Suppression of nNOS and Microglia Activation to Protect Against Neuronal Damage in Kainic Acid-Treated Rats

Abstract

Our previous studies showed that Gastrodia elata (GE), an herb used in traditional Chinese medicine, has both anti-convulsive and free radical-scavenging activities in kainic acid (KA)-treated rats. The aim of the present study was to further investigate possible physiological mechanisms of GE against activities of neuronal nitric oxide synthase (nNOS) and microglia in KA-treated rats; 0.5 g/kg and 1.0 g/kg of GE extract were administered orally, whereas 20 mg/kg of N-nitro-L-arginine methyl ester (L-NAME) was administered intraperitoneally (ip), both at 30 minutes prior to KA (2 microg/2 microl) being injected into the right hippocampus region of rats. ED1-staining, apoptotic, inducible nitric oxide synthase (iNOS), and nNOS-staining cells were observed in the hippocampus region. The results indicated that 1.0 g/kg of GE and 20 mg/kg of L-NAME reduced the counts of ED1-stained cells, and 0.5 g/kg and 1.0 g/kg of GE, and 20 mg/kg of L-NAME reduced the numbers of apoptotic cells and nNOS-staining cells. In addition, 20 mg/kg of L-NAME also reduced the numbers of iNOS-staining cells, but 0.5 g/kg and 1.0 g/kg of GE did not. This study demonstrated that GE was able to reduce nNOS, microglia activation and apoptosis, suggesting that GE has a protective effect against neuronal damage in KA-treated rats.

Anti-inflammatory and anti-angiogenic activities of Gastrodia elata Blume

“…Ether fraction of methanol extract of Gastrodia elata has anticonvulsive and neuroprotective effects against excitotoxicity induced by kainic acid, a powerful excitatory amino acid agonist with excitotoxic and convulsive properties, in the mouse hippocampus (Kim et al, 2003c). Methanol extract of Gastrodia elata reduces neuronal nitric oxide synthase activity, microglia activation and apoptosis in the kainic acid-treated rat hippocampus (Hsieh et al, 2005). It also prevents serum-deprived apoptosis of rat pheochromocytoma cells through activation of the serine/threonine kinase-dependent pathway and suppression of c-Jun NH 2 -terminal kinase (JNK) (Huang et al, 2004).…”

Preventive effect of gastrodin on cognitive decline after cardiac surgery with cardiopulmonary bypass: A double-blind, randomized controlled study

“…Gastrodia elata Blume has shown considerable effects on preventing ischemic brain injury [11] , neuronal cell damage [12][13][14] or apoptosis [12,15] , suppressing inflammatory response [16] , inhibiting glutamine receptors [17] and nNOS [12] , and scavenging free radicals [11,12,18] . Gastrodin (4-[β-D-glucopyranosyloxy] benzyl alcohol, fig.…”

Effect of Gastrodia elata on tumor necrosis factor-alpha-induced matrix metalloproteinase activity in endothelial cells

“…Recently Gastrodia elata was reported as an important medical food to treat vascular diseases [1]. In rat hippocampus, a methanol extract of Gastrodia elata reduced neuronal nitric oxide synthase activity, microglia activation, and apoptosis [2]. However, the effect of ethanol extract of Gastrodia elata rhizome (EGE) on MMP activity associated with atherosclerosis is still unknown.…”