The growth-promoting effects of Chinese medicine Ginkgo biloba leaf extract and its main ingredient quercetin in rat nerve

• Main Authors: Walter Wang, 王金裕
• Other Authors: Yueh-Sheng Chen
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/98733881703563675017

博士 === 中國醫藥大學 === 中醫學系博士班 === 101 === The growth-promoting effects of Chinese medicine Ginkgo biloba leaf extract and its main ingredient quercetin in rat nerve Walter Wang Major professor: Yueh-Sheng Chen Graduate Institute of Chinese Medical, China Medical University According to TCM theory, the traditional Chinese medicine is based on Yiqihuoxue(益氣活血) to treat nerve injury. Ginkgo biloba and its most important bio-active ingredient quercetin have been well known one of their function is to remove the thrombus formation in circulation. The goal of this study is to determine the effects of Ginkgo biloba and quercetin, on nerve regeneration. Using EGb-761(20 mg/kg/day for one week) which is derived from Ginkgo biloba administrated with NMRI mice for a week and investigated whether EGb-761 has function in the regulation of the dopamine receptor D1 expression for nerve growth and development in the frontal cortex of the mouse brain. Moreover, RSC96 cells have been widely used to study cell differentiation and neurite outgrowth. We also applied these cells for study cell morphology, cell survival rate, and nerve growth by difference dose of quercetin (0, 0.1, 1.0 and 10.0 μg∕ml) using MTT and TUNEL assays. To assess quercetin on the recovery of neurological function, we used rat sciatic nerve injury model to fill with quercetin using internal silicone tube and mountings on the truncation of the 15 mm gap. These results of EGb-761-fed mice show more D1A positive cells in the frontal cortex tissue sections, indicating that ginkgo leaf extract is able to modulate nerve growth and development throung increased D1A expression. Moreover, quercetin significantly improves the survival and growth of Schwann cells, RSC96 cells, as well as quercetin is able to promote the number and density of the myelin sheath of axons in rats that were implanted silicone tube in the transected sciatic nerves in rats. These results are consist with electrophysiological examine, quercetin-treated rats have relatively large nerve conduction velocity, the larger action potential duration, amplitude, and CMAP area under the curve. Quercetin can not only improve Schwann cells survival rate, but also can speed up the rat sciatic nerve regeneration and functional recovery. However, high concentrations of quercetin have a negative impact in nerve regeneration. It is still not well understood the role of quercetin in the nerve regeneration. Thus, it is necessary to study it in advance in the future. Keywords: neurotrophic factor;traditional Chinese medicine theory;ginkgo;quercetin;nerve regeneration.