http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Differential Functions of Ras for Malignant Phenotypic Conversion
Moon Aree The Pharmaceutical Society of Korea 2006 Archives of Pharmacal Research Vol.29 No.2
Among the effector molecules connected with the group of cell surface receptors, Ras proteins have essential roles in transducing extracellular signals to diverse intracellular events, by controlling the activities of multiple signaling pathways. For over 20 years since the discovery of Ras proteins, an enormous amount of knowledge has been accumulated as to how the proteins function in overlapping or distinct fashions. The signaling networks they regulate are very complex due to their multiple functions and cross-talks. Much attention has been paid to the pathological role of Ras in tumorigenesis. In particular, human tumors very frequently express Ras proteins constitutively activated by point mutations. Up to date, three members of the Ras family have been identified, namely H-Ras, K-Ras (A and B), and N-Ras. Although these Ras isoforms function in similar ways, many evidences also support the distinct molecular function of each Ras protein. This review summarizes differential functions of Ras and highlights the current view of the distinct signaling network regulated by each Ras for its contribution to the malignant phenotypic conversion of breast epithelial cells. Four issues are addressed in this review: (1) Ras proteins, (2) membrane localization of Ras, (3) effector molecules downstream of Ras, (4) Ras signaling in invasion. In spite of the accumulation of information on the differential functions of Ras, much more remains to be elucidated to understand the Ras-mediated molecular events of malignant phenotypic conversion of cells in a greater detail.
Effect of Glycyrrhiza glabra Roots and Glycyrrhizin on the Glucuronidation in Rats
Moon, Aree,Kim, Seung Hee 德成女子大學校 藥學硏究所 1997 藥學論文誌 Vol.8 No.1
As an approach to elucidate the possible in vivo interaction of synthetic drugs and herbs which are frequently used in combination in Asia, the effect of Glycyrthiza glabra on the metabolism of acetaminophen (AAP) was examined in male Sprague-Dawley rats. The pretreatment of the methanol extract of Glycyrrhiza glabra roots (Glycyrrhizae Radix, GR, 1g/kg, p.o.) for 6 days significantly increased the cumulative biliary(156%) and urinary (132%) excretions of AAP-glucuronide conjugate within 120 min after the administration of AAP-glucuronide confugate wihtin 120 min after the administration of AAP(150 mg/kg, i.v.) without affecting thioether and sulfate conjugates. These findings suggest that GR might enhance the glucuronidation pathway of AAP. In order to study the effect of GR on the glucuronidation in rat liver, we examined enzymatic activity of p-nitrophenol UDP-glucuronosyltransferase (UGT), which is also called UGT1A, and intracellular concentrations of hepatic UDP-glucuronic acid, upon the administration of GR(1g/lkg,p.o.) or glycyrrhizin (23 mg/kg, p.o.), a major component of GR, for 6 days. GR and glycyrrhizin caused increases in specific activities of UGT1A by 111% and 96%, respectively. Concentration of UDP-glucuronic acid was increased 257% by GR and 484% by glycyrrhizin. These data indicate that GR and glycyrrhizin activated glucuronidation and thus suggest the possibility that GR may influence detoxification of xenobiotics in rat liver. Using the p-nitrophenol UGT1A1 cDNA as a probe, we found that the activation of UGT1A by GR was not due to the induction of mRNAs for the enzyme.