Differential effects of the steaming time and frequency for manufactured             red Liriope platyphylla on nerve growth factor secretion ability, nerve growth             factor receptor signaling pathway and regulation of calcium concentration.
The herb Liriope platyphylla (LP) has been considered to have curative properties             for diabetes, asthma and neurodegenerative disorders. To examine the effects of             steaming time and frequency of manufactured red LP (RLP) on the nerve growth factor             (NGF) secretion ability and NGF receptor signaling pathway, the NGF concentration,             cell differentiation, NGF signaling pathway and calcium concentration were analyzed             in neuronal cells treated with several types of LPs manufactured under different             conditions. The maximum NGF secretion was observed in B35 cells treated with 50             µg/ml LP extract steamed for 9 h (9-SLP) and with two repeated steps (3 h steaming             and 24 h air-dried) carried out 7 times (7-SALP). No significant changes in viability             were detected in any of the cells treated with the various LPs, with the exception             of 0-SLP and 0-SALP. In addition, PC12 cell differentiation was induced by treatment             with the NGF-containing conditional medium (CM) collected from the RLP-treated             cells. The levels of TrkA and extracellular signal-regulated kinase (ERK) phosphorylation             in the high affinity NGF receptor signaling pathway were significantly higher             in the cells treated with 3-SLP or 1-SALP/3-SALP CM compared with those treated             with the vehicle CM. In the low affinity NGF receptor pathway, the expression             levels of most components were higher in the 9-, 15- and 24-SALP CM-treated cells             compared with the vehicle CM-treated cells. However, this level was significantly             altered in cells treated with 3-SALP CM. Furthermore, an examination of the RLP             function on calcium regulation revealed that only the LP- or RLP-treated cells             exhibited changes in intracellular and extracellular calcium levels. RLP induced             a significant decrease in the intracellular calcium levels and an increase in             the extracellular calcium levels. These results suggest the possibility that steaming-processed             LP may aid in the relief of neurodegenerative diseases through the NGF secretion             ability and NGF signaling pathway.
College of Natural Resources and Life Science, Pusan National                     University, Miryang 627-706, Republic of Korea.
Sun Il
SI
Choi
Jun Seo
JS
Goo
Ji Eun
JE
Kim
So Hee
SH
Nam
In Sik
IS
Hwang
Hye Ryun
HR
Lee
Young Ju
YJ
Lee
Hong Joo
HJ
Son
Hee Seob
HS
Lee
Jong Sup
JS
Lee
Hak Jin
HJ
Kim
Dae Youn
DY
Hwang
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D031424:Liriope Plant / Q000737:chemistry*; D020932:Nerve Growth Factor / Q000378:metabolism*; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D016716:PC12 Cells; D010936:Plant Extracts / Q000494:pharmacology; D018517:Plant Roots / Q000737:chemistry; D051381:Rats; D020917:Receptor, trkA / Q000378:metabolism; D017475:Receptors, Nerve Growth Factor / Q000378:metabolism*; D015398:Signal Transduction; D013696:Temperature
D010936:Plant Extracts; D017475:Receptors, Nerve Growth Factor; D020932:Nerve Growth Factor; D020917:Receptor, trkA; D048049:Extracellular Signal-Regulated MAP Kinases; D002118:Calcium