Biomedical subjects

Gao-yun Hu

Publications and source records attributed to Gao-yun Hu.

5 recordsLinked to original sources

PubMed2006

[Oxidative stress in nitroglycerin tolerance and treatment with 3,4,5,6-tetrahydroxyxanthone].

OBJECTIVE: To determine the relationship between the nitroglycerin tolerance and the stimulation of radical oxygen species (ROS) production, and the therapeutical effect of 3,4,5,6-tetrahydroxyxanthone. METHODS: Vasodilator responses to nitroglycerin were examined in the isolated thoracic aorta. The contents of ROS,and cGMP were determined in the cultured human umbilical vein endothelial cells. RESULTS: 3,4,5,6-tetrahydroxyxanthone could significantly reduce the inhibition of relaxation by nitroglycerin. 3,4,5,6-tetrahydroxyxanthone could significantly inhibit the ROS increase and increase the cGMP level. CONCLUSION: Nitroglycerin tolerance is associated with the stimulation of ROS production,and the reversal of nitroglycerin tolerance with 3,4,5,6-tetrahydroxyxanthone is related to the reduction of ROS.

Animals↗

PubMed2004

[Water-soluble chemical constituents of Swertia davidi Franch].

AIM: To study the active constituents of Swertia davidi Franch. METHODS: Column chromatographies on silica gel, Sephadex LH-20 and Diaion-201 et al. were used to isolate and purify the chemical components. Their structures were identified by UV, IR, MS, NMR and 2D-NMR. RESULTS: These compounds were elucidated as 8-O-beta-D-glucopyranosyl-1, 3, 5-trihydroxyxanthone (I), 5-O-beta-D-glucopyranosyl-1, 8-dihydroxy-3-methoxyxanthone (II), 5-O-beta-D-glucopyranosyl-1, 3, 8-trihydroxyxanthone (III) and swertamarin (IV). CONCLUSION: Compound III is a new xanthone glucoside. The other compounds were isolated from this plant for the first time.

Glucosides↗

PubMed2004

[A new xanthone from Polygala aureocauda Dunn].

AIM: To study the chemical constituents of Polygala aureocauda Dunn.. METHODS: Chemical compounds were isolated by column chromatography and their structures were determined mainly by spectroscopic means (UV, IR, MS, 1HNMR, 13CNMR, HMQC, HMBC). RESULTS: Three compounds were isolated and identified as 3-hydroxy-1,4-dimethoxyxanthone (I), 1, 7-dihydroxy-2, 3-methylendioxyxanthone (II), 7-hydroxy-1-methoxy-2, 3-methylendioxyxanthone (III). CONCLUSION: Compounds I-III were isolated from Polygala aureocauda Dunn. for the first time, whereas compound I is a new xanthone.

Molecular Conformation↗

PubMed2003

[Daviditin B from Swertia davidi Franch].

AIM: To study the active constituents of Swertia davidi Franch. METHODS: Chemical components were isolated by column chromatography and their structures were established mainly by spectroscopic means (UV, IR, NMR, 2D-NMR, MS). RESULTS: Three substances were identified as 2,5-dimethoxyl-1, 4-dicarboxyl benzene (VIII), 1,5,8-trihydroxyl-3,4-dimethoxyl xanthone (IX) and 1,8-dihydroxyl-3-(3'-hydroxyl-butoxy) xanthone (X). CONCLUSION: Compounds VIII and IX were isolated from Swertia davidi Franch, for the first time, whereas compound X is a new xanthone, named daviditin B with antioxygenated activity in vitro.

Antioxidants↗

PubMed2002

[Studies of the chemical constituents of Swertia davida Franch].

AIM: To study the active constituents of Swertia davidi Franch.. METHODS: Chromatography was used to isolate and purify the chemical components, their structures were identified by spectral analysis. RESULTS: Three compounds were identified as 1,7-dihydroxy-3,8-dimethoxyxanthone (gentiacaulein) (V), 1,8-dihydroxy-3,7-dimethoxyxanthone (methylswertianin) (VI) and 1,8-dihydroxy-3,4,7-trimethoxyxanthone (VII). CONCLUSION: Compound VII is a novel xanthone, named daviditin A, the others were isolated from Swertia davidi Franch. for the first time.

Molecular Structure↗