Neuromuscular junction is the main target for snakebites, which venoms act depending on the snake genus for paralyzing the prey （neurotoxicity） or for facilitating the digestion processes of the victim （myotoxicity...Neuromuscular junction is the main target for snakebites, which venoms act depending on the snake genus for paralyzing the prey （neurotoxicity） or for facilitating the digestion processes of the victim （myotoxicity）, and also as a defense mechanism against predators. In the present study, a mouse neuromuscular apparatus was used for testing the hexane fraction of Casearia gossypiosperma plant, that showed the better antiophidian ability than dichloromethane, ethyl acetate and methanol fractions, against the irreversible paralysis induced by two, Bothrops jararacussu （Bjssu, 40 μg/mL） and Crotalus durissus terrificus （Cdt, 10 μg/mL） snake venoms. All fractions were obtained by liquid-liquid partition from the C. gossypiosperma hydroalcoholic lyophilized extract. The preliminary chromatographic profile of this plant showed phenols and flavonols as active constituents, whereas hexane fraction expressed mainly 13-sitosterol and quercetin. In spite of hexane fraction protection （≌95% and 48% against Bjssu and Cdt, respectively）, isolately, only quercetin protected against the blockade-induced by Bjssu venom （65.5%）. This study showed that hexane fraction acts against these snake venoms by a synergistic phytocomplex mechanism.展开更多
Eight novel clerodane diterpenoids(1-8)were isolated from the twigs of Casearia graveolens.Their structures were elucidated through comprehensive nuclear magnetic resonance(NMR),high-resolution electrospray ionization...Eight novel clerodane diterpenoids(1-8)were isolated from the twigs of Casearia graveolens.Their structures were elucidated through comprehensive nuclear magnetic resonance(NMR),high-resolution electrospray ionization mass spectrometry(HRESI-MS),and electronic circular dichroism(ECD)analyses.In addition to structural determination,surface plasmon resonance(SPR)assays were conducted to investigate molecular interactions,revealing that compound 8 exhibited high affinity for vascular endothelial growth factor receptor 2(VEGFR2),a key regulator of tumor angiogenesis.Subsequent in vivo experiments demonstrated that compound 8 effectively inhibited angiogenesis and displayed significant antitumor activity by suppressing tumor proliferation and metastasis in zebrafish xenograft models.These findings suggest that compound 8 holds promise as an anticancer lead compound targeting VEGFR-2 to obstruct tumor angiogenesis.展开更多
To investigate the chemical components from the stems of Casearia velutina Bl.,the constituents were isolated by repeated chromatography with silica gel,Sephadex LH-20,and ODS columns.The structures were elucidated by...To investigate the chemical components from the stems of Casearia velutina Bl.,the constituents were isolated by repeated chromatography with silica gel,Sephadex LH-20,and ODS columns.The structures were elucidated by spectroscopic analysis.Eleven triterpenoids and its glycosides were isolated from the crude extract of C.velutina,and their structures were identified as friedelin-2,3-lactone（1）,friedelane（2）,epifriedelanol（3）,friedelin（4）,2α,3α,19α-trihydroxy-urs-12-en-28-oic acid（5）,2α,3β,19α-trihydroxy-urs-12-en-28-oic acid（6）,2α,3α,23-trihydroxy-urs-12-en-28-oic acid（7）,2α,3α,23-trihydroxy-olean-12-en-28-oic acid（8）,2α,3α,19α,23-tetrahydroxy-urs-12-en-28-oic acid（9）,2α,3α,19α,23-tetrahydroxy-urs-12-en-28-oic acid-28-O-β-D-glucopyranosyl ester（10）,and 3β,19α-dihydroxy-urs-12-en-28-oic acid 3-O-α-L-arabinopyranoside（11）.All the compounds described above were isolated from this species for the first time.Compound 1 is a rarely occurred seco-friedelolactone in Flacourtiaceae.展开更多
文摘Neuromuscular junction is the main target for snakebites, which venoms act depending on the snake genus for paralyzing the prey （neurotoxicity） or for facilitating the digestion processes of the victim （myotoxicity）, and also as a defense mechanism against predators. In the present study, a mouse neuromuscular apparatus was used for testing the hexane fraction of Casearia gossypiosperma plant, that showed the better antiophidian ability than dichloromethane, ethyl acetate and methanol fractions, against the irreversible paralysis induced by two, Bothrops jararacussu （Bjssu, 40 μg/mL） and Crotalus durissus terrificus （Cdt, 10 μg/mL） snake venoms. All fractions were obtained by liquid-liquid partition from the C. gossypiosperma hydroalcoholic lyophilized extract. The preliminary chromatographic profile of this plant showed phenols and flavonols as active constituents, whereas hexane fraction expressed mainly 13-sitosterol and quercetin. In spite of hexane fraction protection （≌95% and 48% against Bjssu and Cdt, respectively）, isolately, only quercetin protected against the blockade-induced by Bjssu venom （65.5%）. This study showed that hexane fraction acts against these snake venoms by a synergistic phytocomplex mechanism.
基金supported by the National Natural Science Foundation of China(No.22077067)the Project of State Key Laboratory of Functions and Applications of Medicinal Plants,Guizhou Medical University[No.QJJ(2022)422]the 111 Project(No.B20016)。
文摘Eight novel clerodane diterpenoids(1-8)were isolated from the twigs of Casearia graveolens.Their structures were elucidated through comprehensive nuclear magnetic resonance(NMR),high-resolution electrospray ionization mass spectrometry(HRESI-MS),and electronic circular dichroism(ECD)analyses.In addition to structural determination,surface plasmon resonance(SPR)assays were conducted to investigate molecular interactions,revealing that compound 8 exhibited high affinity for vascular endothelial growth factor receptor 2(VEGFR2),a key regulator of tumor angiogenesis.Subsequent in vivo experiments demonstrated that compound 8 effectively inhibited angiogenesis and displayed significant antitumor activity by suppressing tumor proliferation and metastasis in zebrafish xenograft models.These findings suggest that compound 8 holds promise as an anticancer lead compound targeting VEGFR-2 to obstruct tumor angiogenesis.
基金Changjiang Scholar and Innovative Team in University (Grant No. 985-2-063-112)
文摘To investigate the chemical components from the stems of Casearia velutina Bl.,the constituents were isolated by repeated chromatography with silica gel,Sephadex LH-20,and ODS columns.The structures were elucidated by spectroscopic analysis.Eleven triterpenoids and its glycosides were isolated from the crude extract of C.velutina,and their structures were identified as friedelin-2,3-lactone（1）,friedelane（2）,epifriedelanol（3）,friedelin（4）,2α,3α,19α-trihydroxy-urs-12-en-28-oic acid（5）,2α,3β,19α-trihydroxy-urs-12-en-28-oic acid（6）,2α,3α,23-trihydroxy-urs-12-en-28-oic acid（7）,2α,3α,23-trihydroxy-olean-12-en-28-oic acid（8）,2α,3α,19α,23-tetrahydroxy-urs-12-en-28-oic acid（9）,2α,3α,19α,23-tetrahydroxy-urs-12-en-28-oic acid-28-O-β-D-glucopyranosyl ester（10）,and 3β,19α-dihydroxy-urs-12-en-28-oic acid 3-O-α-L-arabinopyranoside（11）.All the compounds described above were isolated from this species for the first time.Compound 1 is a rarely occurred seco-friedelolactone in Flacourtiaceae.
