TY - JOUR
T1 - Mechanisms of suppression of nitric oxide production by 3-O-methylquercetin in RAW 264.7 cells
AU - Jiang, Jiunn Song
AU - Shih, Chwen Ming
AU - Wang, Sheng Hao
AU - Chen, Tzu Ting
AU - Lin, Chun Nan
AU - Ko, Wun-Chang
PY - 2006/1/16
Y1 - 2006/1/16
N2 - Rhamnus nakaharai Hayata (Rhamnaceae) is used as a folk medicine in Taiwan for treating constipation, inflammation, tumors, and asthma. 3-O-Methylquercetin (3-MQ), a main constituent of the plant, has been reported to have potential for use in the treatment of asthma. The mechanisms of anti-inflammation of 3-MQ are still unclear. Nitric oxide (NO) production induced by lipopolysaccharide (LPS) through iNOS expression in RAW 264.7 cells, a mouse macrophage cell line, may reflect the degree of inflammation and may provide a measure for assessing the effect of drugs on the inflammatory process. Therefore, we were interested in investigating the mechanisms of suppression of NO production by 3-MQ in RAW 264.7 cells. 3-MQ (1-10 μM) concentration-dependently inhibited LPS (100 ng/mL)-induced NO production in RAW 264.7 cells. The IC50 value was calculated to be 4.23 μM. 3-MQ (1-10 μM) significantly and concentration-dependently inhibited LPS (100 ng/mL)-induced iNOS protein and mRNA expressions in cells. The IC50 values were calculated to be 4.36 and 6.53 μM, respectively. There was no significant difference among these three IC50 values of 3-MQ. In conclusion, 3-MQ may exert its anti-inflammatory effect through the inhibition of iNOS DNA transcription.
AB - Rhamnus nakaharai Hayata (Rhamnaceae) is used as a folk medicine in Taiwan for treating constipation, inflammation, tumors, and asthma. 3-O-Methylquercetin (3-MQ), a main constituent of the plant, has been reported to have potential for use in the treatment of asthma. The mechanisms of anti-inflammation of 3-MQ are still unclear. Nitric oxide (NO) production induced by lipopolysaccharide (LPS) through iNOS expression in RAW 264.7 cells, a mouse macrophage cell line, may reflect the degree of inflammation and may provide a measure for assessing the effect of drugs on the inflammatory process. Therefore, we were interested in investigating the mechanisms of suppression of NO production by 3-MQ in RAW 264.7 cells. 3-MQ (1-10 μM) concentration-dependently inhibited LPS (100 ng/mL)-induced NO production in RAW 264.7 cells. The IC50 value was calculated to be 4.23 μM. 3-MQ (1-10 μM) significantly and concentration-dependently inhibited LPS (100 ng/mL)-induced iNOS protein and mRNA expressions in cells. The IC50 values were calculated to be 4.36 and 6.53 μM, respectively. There was no significant difference among these three IC50 values of 3-MQ. In conclusion, 3-MQ may exert its anti-inflammatory effect through the inhibition of iNOS DNA transcription.
KW - 3-O-Methylquercetin
KW - Anti-inflammation
KW - Rhamnaceae
KW - Rhamnus nakaharai
KW - iNOS mRNA expression
KW - iNOS protein expression
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UR - http://www.scopus.com/inward/citedby.url?scp=29144509817&partnerID=8YFLogxK
U2 - 10.1016/j.jep.2005.08.005
DO - 10.1016/j.jep.2005.08.005
M3 - Article
C2 - 16213685
AN - SCOPUS:29144509817
SN - 0378-8741
VL - 103
SP - 281
EP - 287
JO - Journal of Ethnopharmacology
JF - Journal of Ethnopharmacology
IS - 2
ER -