Neuroprotective effects of medicinal plants.



As human life expectancy has increased, so too has the incidence of age-related neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, and Huntington's disease (Borgesius et al., 2011[4]). Plant extracts have a wide range of medicinal actions, and throughout history, they have been used to treat many different types of diseases. More recently, however, scientists have begun investigating the biological activities of medicinal plants, including their neuroprotective actions. For example Lycium chinense Miller, which is a traditional herbal medicine used in China, Korea, and Japan, has been shown to have hypotensive, hypoglycemic, and antipyretic effects in animal studies following treatment with the fruit and root bark of the plant (Potterat, 2010[19]; Lee et al., 2004[15]). Furthermore, this plant has been used as an anti-aging therapy and a treatment for neurodegenerative diseases (Ho et al., 2010[6]; Potterat, 2010[19]), and recent research has confirmed neuroprotective effects of the fruit of the plant in a rat model of trimethyltin-induced learning and memory impairment (Park et al., 2011[17]). Other plants have also shown neuroprotective effects. In separate studies, extracts of Camellia sinensis and Erigeron breviscapus demonstrated neuroprotective effects against hydrogen peroxide-induced toxicity in PC12 cells (López and Calvo, 2011[16]; Hong and Liu, 2004[8]), and Smilacis chinae Rhizome exhibited a neuroprotective effect in an in vitro model of N-methyl-d-aspartate-induced neurotoxicity; it showed a similar effect in an in vivo model of focal cerebral ischemia. Studies investigating the neuroprotective actions of various medicinal plants are shown in Table 1(Tab. 1) (References in Table 1: Bastianetto et al., 2000[2]; Koo et al., 2004[13]; Koo et al., 2004[12]; Yu et al., 2005[22]; Jia et al., 2005[9]; Bastianetto et al., 2006[3]; Ho et al., 2007[7]; Yun et al., 2007[23]; Ban et al., 2008[1]; Shim et al., 2009[20]; Kim et al., 2010[11]; Choi et al., 2011[5]; López and Calvo, 2011[16]; Park et al., 2011[18]; Lee et al., 2011[14]; Park et al., 2011[18]; Yao et al., 2011[21]; Keo et al., 2012[10]).

Table 1

Studies investigating the neuroprotective effects of medicinal plants

Notes

Jai-Heon Lee and Sang Un Park (Department of Crop Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon, 305-764, Korea; Phone: +82-42-821-5730, E-mail: supark@cnu.ac.kr) contributed equally as corresponding authors.