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Sonia Cheung - One of the best experts on this subject based on the ideXlab platform.
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light might regulate divergently Depside and depsidone accumulation in the lichen parmotrema hypotropum by affecting thallus temperature and water potential
Mycologia, 2008Co-Authors: Daniele Armaleo, Yi Zhang, Sonia CheungAbstract:Depsides and depsidones are the most common secondary products uniquely produced in lichens by the fungal symbiont, and they accumulate on the outer surface of its hyphae. Their biological roles are subject to debate. Quantitatively the compounds typical of a given lichen can vary dramatically from thallus to thallus. Several studies have addressed whether this variability is correlated with the light reaching different thalli, but the conclusions are contradictory. We addressed the question with the lichen Parmotrema hypotropum growing on unshaded, vertical tree trunks, a con- trolled natural environment where the light absorbed by each thallus over its lifetime is the only major position-dependent variable. The exact north-east- south-west orientation of each thallus was used to calculate its yearly light exposure based on astronom- ical and meteorological considerations. The calculat- ed irradiation around the trunk, distributed over a continuous 40-fold intensity range, then was com- pared with the amount of compound per unit thallus weight, determined by quantitative thin layer chro- matography. P. hypotropum accumulates the Depside atranorin in the cortex and the depsidone norstictic acid in the medulla and around the algae. A direct correlation was observed between the yearly amount of light reaching the lichen and the amount of atranorin. In contrast, the amount of norstictic acid decreased with increasing light. Although we did not measure thallus temperature and water potential, a unifying interpretation of these and other published data is that Depside/depsidone accumulation in
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light might regulate divergently Depside and depsidone accumulation in the lichen parmotrema hypotropum by affecting thallus temperature and water potential
Mycologia, 2008Co-Authors: Daniele Armaleo, Yi Zhang, Sonia CheungAbstract:Depsides and depsidones are the most common secondary products uniquely produced in lichens by the fungal symbiont, and they accumulate on the outer surface of its hyphae. Their biological roles are subject to debate. Quantitatively the compounds typical of a given lichen can vary dramatically from thallus to thallus. Several studies have addressed whether this variability is correlated with the light reaching different thalli, but the conclusions are contradictory. We addressed the question with the lichen Parmotrema hypotropum growing on unshaded, vertical tree trunks, a controlled natural environment where the light absorbed by each thallus over its lifetime is the only major position-dependent variable. The exact north-east-south-west orientation of each thallus was used to calculate its yearly light exposure based on astronomical and meteorological considerations. The calculated irradiation around the trunk, distributed over a continuous 40-fold intensity range, then was compared with the amount of compound per unit thallus weight, determined by quantitative thin layer chromatography. P. hypotropum accumulates the Depside atranorin in the cortex and the depsidone norstictic acid in the medulla and around the algae. A direct correlation was observed between the yearly amount of light reaching the lichen and the amount of atranorin. In contrast, the amount of norstictic acid decreased with increasing light. Although we did not measure thallus temperature and water potential, a unifying interpretation of these and other published data is that Depside/depsidone accumulation in lichens is mediated by localized changes in temperature and water potential produced by light absorption within each thallus. This suggests water relations-based functions for Depsides and depsidones.
Daniele Armaleo - One of the best experts on this subject based on the ideXlab platform.
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insights from the first putative biosynthetic gene cluster for a lichen Depside and depsidone
Mycologia, 2011Co-Authors: Daniele Armaleo, Xiameng Sun, Chicita F CulbersonAbstract:The genes for polyketide synthases (PKSs), enzymes that assemble the carbon backbones of many secondary metabolites, often cluster with other sec- ondary pathway genes. We describe here the first lichen PKS cluster likely to be implicated in the biosynthesis of a Depside and a depsidone, compounds in a class almost exclusively produced by lichen fungi (mycobionts). With degenerate PCR with primers biased toward presumed PKS genes for Depsides and depsidones we identified among the many PKS genes in Cladonia grayi four (CgrPKS13-16) potentially responsible for grayanic acid (GRA), the orcinol depsidone characteristic of this lichen. To single out a likely GRA PKS we compared mRNA and GRA induction in mycobiont cultures using the four candi- date PKS genes plus three controls; only CgrPKS16 expression closely matched GRA induction. CgrPKS16 protein domains were compatible with orcinol Depside biosynthesis. Phylogenetically CgrPKS16 fell in a new subclade of fungal PKSs uniquely producing orcinol compounds. In the C. grayi genome CgrPKS16 clus- tered with a CytP450 and an O-methyltransferase gene, appropriately matching the three compounds in the GRA pathway. Induction, domain organization, phylog- eny and cluster pathway correspondence independently indicated that the CgrPKS16 cluster is most likely responsible for GRA biosynthesis. Specifically we propose that (i) a single PKS synthesizes two aromatic rings and links them into a Depside, (ii) the Depside to depsidone transition requires only a cytochrome P450 and (iii) lichen compounds evolved early in the radiation of filamentous fungi.
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light might regulate divergently Depside and depsidone accumulation in the lichen parmotrema hypotropum by affecting thallus temperature and water potential
Mycologia, 2008Co-Authors: Daniele Armaleo, Yi Zhang, Sonia CheungAbstract:Depsides and depsidones are the most common secondary products uniquely produced in lichens by the fungal symbiont, and they accumulate on the outer surface of its hyphae. Their biological roles are subject to debate. Quantitatively the compounds typical of a given lichen can vary dramatically from thallus to thallus. Several studies have addressed whether this variability is correlated with the light reaching different thalli, but the conclusions are contradictory. We addressed the question with the lichen Parmotrema hypotropum growing on unshaded, vertical tree trunks, a con- trolled natural environment where the light absorbed by each thallus over its lifetime is the only major position-dependent variable. The exact north-east- south-west orientation of each thallus was used to calculate its yearly light exposure based on astronom- ical and meteorological considerations. The calculat- ed irradiation around the trunk, distributed over a continuous 40-fold intensity range, then was com- pared with the amount of compound per unit thallus weight, determined by quantitative thin layer chro- matography. P. hypotropum accumulates the Depside atranorin in the cortex and the depsidone norstictic acid in the medulla and around the algae. A direct correlation was observed between the yearly amount of light reaching the lichen and the amount of atranorin. In contrast, the amount of norstictic acid decreased with increasing light. Although we did not measure thallus temperature and water potential, a unifying interpretation of these and other published data is that Depside/depsidone accumulation in
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light might regulate divergently Depside and depsidone accumulation in the lichen parmotrema hypotropum by affecting thallus temperature and water potential
Mycologia, 2008Co-Authors: Daniele Armaleo, Yi Zhang, Sonia CheungAbstract:Depsides and depsidones are the most common secondary products uniquely produced in lichens by the fungal symbiont, and they accumulate on the outer surface of its hyphae. Their biological roles are subject to debate. Quantitatively the compounds typical of a given lichen can vary dramatically from thallus to thallus. Several studies have addressed whether this variability is correlated with the light reaching different thalli, but the conclusions are contradictory. We addressed the question with the lichen Parmotrema hypotropum growing on unshaded, vertical tree trunks, a controlled natural environment where the light absorbed by each thallus over its lifetime is the only major position-dependent variable. The exact north-east-south-west orientation of each thallus was used to calculate its yearly light exposure based on astronomical and meteorological considerations. The calculated irradiation around the trunk, distributed over a continuous 40-fold intensity range, then was compared with the amount of compound per unit thallus weight, determined by quantitative thin layer chromatography. P. hypotropum accumulates the Depside atranorin in the cortex and the depsidone norstictic acid in the medulla and around the algae. A direct correlation was observed between the yearly amount of light reaching the lichen and the amount of atranorin. In contrast, the amount of norstictic acid decreased with increasing light. Although we did not measure thallus temperature and water potential, a unifying interpretation of these and other published data is that Depside/depsidone accumulation in lichens is mediated by localized changes in temperature and water potential produced by light absorption within each thallus. This suggests water relations-based functions for Depsides and depsidones.
Yi Zhang - One of the best experts on this subject based on the ideXlab platform.
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light might regulate divergently Depside and depsidone accumulation in the lichen parmotrema hypotropum by affecting thallus temperature and water potential
Mycologia, 2008Co-Authors: Daniele Armaleo, Yi Zhang, Sonia CheungAbstract:Depsides and depsidones are the most common secondary products uniquely produced in lichens by the fungal symbiont, and they accumulate on the outer surface of its hyphae. Their biological roles are subject to debate. Quantitatively the compounds typical of a given lichen can vary dramatically from thallus to thallus. Several studies have addressed whether this variability is correlated with the light reaching different thalli, but the conclusions are contradictory. We addressed the question with the lichen Parmotrema hypotropum growing on unshaded, vertical tree trunks, a con- trolled natural environment where the light absorbed by each thallus over its lifetime is the only major position-dependent variable. The exact north-east- south-west orientation of each thallus was used to calculate its yearly light exposure based on astronom- ical and meteorological considerations. The calculat- ed irradiation around the trunk, distributed over a continuous 40-fold intensity range, then was com- pared with the amount of compound per unit thallus weight, determined by quantitative thin layer chro- matography. P. hypotropum accumulates the Depside atranorin in the cortex and the depsidone norstictic acid in the medulla and around the algae. A direct correlation was observed between the yearly amount of light reaching the lichen and the amount of atranorin. In contrast, the amount of norstictic acid decreased with increasing light. Although we did not measure thallus temperature and water potential, a unifying interpretation of these and other published data is that Depside/depsidone accumulation in
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light might regulate divergently Depside and depsidone accumulation in the lichen parmotrema hypotropum by affecting thallus temperature and water potential
Mycologia, 2008Co-Authors: Daniele Armaleo, Yi Zhang, Sonia CheungAbstract:Depsides and depsidones are the most common secondary products uniquely produced in lichens by the fungal symbiont, and they accumulate on the outer surface of its hyphae. Their biological roles are subject to debate. Quantitatively the compounds typical of a given lichen can vary dramatically from thallus to thallus. Several studies have addressed whether this variability is correlated with the light reaching different thalli, but the conclusions are contradictory. We addressed the question with the lichen Parmotrema hypotropum growing on unshaded, vertical tree trunks, a controlled natural environment where the light absorbed by each thallus over its lifetime is the only major position-dependent variable. The exact north-east-south-west orientation of each thallus was used to calculate its yearly light exposure based on astronomical and meteorological considerations. The calculated irradiation around the trunk, distributed over a continuous 40-fold intensity range, then was compared with the amount of compound per unit thallus weight, determined by quantitative thin layer chromatography. P. hypotropum accumulates the Depside atranorin in the cortex and the depsidone norstictic acid in the medulla and around the algae. A direct correlation was observed between the yearly amount of light reaching the lichen and the amount of atranorin. In contrast, the amount of norstictic acid decreased with increasing light. Although we did not measure thallus temperature and water potential, a unifying interpretation of these and other published data is that Depside/depsidone accumulation in lichens is mediated by localized changes in temperature and water potential produced by light absorption within each thallus. This suggests water relations-based functions for Depsides and depsidones.
Yiping Wang - One of the best experts on this subject based on the ideXlab platform.
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pharmacological actions and therapeutic applications of salvia miltiorrhiza Depside salt and its active components
Acta Pharmacologica Sinica, 2012Co-Authors: Yiping WangAbstract:Salvia miltiorrhiza, a traditional medical herb known as danshen, has been widely used in China to improve blood circulation, relieve blood stasis, and treat coronary heart disease. S miltiorrhiza Depside salt is a novel drug recently developed at the Shanghai Institute of Materia Medica; it contains magnesium lithospermate B (MLB) and its analogs, rosmarinic acid (RA) and lithospermic acid (LA), as active components. The drug has been used in the clinic to improve blood circulation and treat coronary heart disease. The pharmacological effects of the Depside salt from S miltiorrhiza and its components have been extensively investigated. Experimental studies have demonstrated that magnesium lithospermate B possesses a variety of biological activities, especially protective effects in the cardiovascular system such as attenuation of atherosclerosis and protection against myocardial ischemia-reperfusion injury. Rosmarinic acid and lithospermic acid also show beneficial effects on the cardiovascular system. This paper reviews the recent findings regarding the mechanisms underlying the pharmacological actions of the active components of S miltiorrhiza Depside salt, based on published works and our own observations.
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pharmacokinetics of Depside salts from salvia miltiorrhiza in healthy chinese volunteers a randomized open label single dose study
Current Therapeutic Research-clinical and Experimental, 2010Co-Authors: Jingying Jia, Gangyi Liu, Yun Liu, Yanmei Liu, Yiping WangAbstract:Background: Depside salts from Salvia miltiorrhiza, with active components of lithospermic acid B (LSB), rosmarinic acid (RA), and lithospermic acid (LA), are a multicomponent drug marketed in China for the treatment of coronary heart disease. Objectives: The aims of this study were to determine the concentrations of LSB, RA, and LA in human plasma and urine, and to compare the pharmacokinetic properties of Depside salts from S miltiorrhiza in healthy Chinese volunteers. Methods: A randomized, open-label, single-dose study was conducted in healthy Chinese volunteers. Participants were randomly assigned to receive a single intravenous infusion of 100 or 200 mg of Depside salts from S miltiorrhiza. Blood was collected through a venous cannula prior to study drug administration (0 min) and at 10, 20, 30, 60, 65, 70, 80, and 90 minutes and 2, 3, 4, 6, 8, 12, and 24 hours after study drug administration. Urine samples were taken before study drug administration (0) and at 0 to 12 and 12 to 24 hours after study drug administration. LSB, RA, and LA concentrations in serum and urine were analyzed by an LC-MS/MS method. Tolerability was determined by clinical assessment; vital signs (ie, blood pressure, heart rate, breathing rate, body temperature) monitoring at baseline and at the end of the study, clinical laboratory tests (ie, hematology, blood biochemistry, hepatic function, renal function, urinalysis), 12-lead ECG measurements, and physical examinations at baseline and after completion of the study. Results: Twelve Chinese volunteers (6 males, 6 females; mean [SD] age, 25.2 [3.8] years; mean height, 165.7 [8.9] cm; mean body mass index, 21.6 [2.5] kg/m2) were enrolled in the study. Peak plasma concentrations of LSB, RA and LA were observed at 0.3 to 1 hour following the 1-hour intravenous infusion, with respective mean (SD) Cmax of 4925 (1861), 174 (61), and 361 (101) ng/mL for the 100-mg dose and 10,285 (2259), 308 (77), and 674 (85) ng/mL for the 200-mg dose. The AUClast values for LSB, RA, and LA were 4537 (1265), 129 (28), and 1229 (330) ng/mL/h, respectively, for the 100-mg dose and 10,426 (2589), 260 (53), and 2792 (729) ng/mL/h for the 200-mg dose. No significant difference in pharmacokinetic parameters was observed between male and female subjects. Three metabolites were found in the plasma with low concentrations. The urinary excretion recoveries of LSB, RA, and LA were 0.58% (0.42%), 25.21% (20.61%), and 10.02% (7.72%) for the 100-mg dose and 0.38% (0.18%), 20.11% (10.50%), and 6.34% (3.20%) for the 200-mg dose. No adverse events were reported by the subjects or found by the investigators in the analysis of vital signs, 12-lead ECG measurements, physical examinations, or clinical laboratory tests. Conclusions: Following single intravenous infusion of 100 or 200 mg of Depside salts from S miltiorrhiza to healthy Chinese subjects, no statistical differences in pharmacokinetic parameters were observed between males and females. The 2 doses of Depside salts from S miltiorrhiza were clinically well tolerated during the study.
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Depside salts from salvia miltiorrhiza improve myocardial microperfusion in rats using laser doppler flowmetry
Acta Pharmacologica Sinica, 2007Co-Authors: Yiping WangAbstract:Depside salts from Salvia miltiorrhiza improve myocardial microperfusion in rats using laser Doppler flowmetry
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pharmacokinetics tissue distribution metabolism and excretion of Depside salts from salvia miltiorrhiza in rats
Drug Metabolism and Disposition, 2007Co-Authors: Lijiang Xuan, Yiping WangAbstract:Salviae miltiorrhiza, a traditional Chinese medical herb known as "Danshen," has been widely used in clinics to improve blood circulation, relieve blood stasis, and treat coronary heart disease. Depside salts from S. miltiorrhiza are a novel drug in which magnesium lithospermate B and its analogs are the active components. The pharmacokinetics, tissue distribution, metabolism, and excretion of three of the major components, lithospermic acid B, rosmarinic acid (RA), and lithospermic acid (LA), were studied by liquid chromatography-tandem mass spectrometry following intravenous administration in Sprague-Dawley rats. The elimination half-lives for LSB, RA, and LA were 1.04, 0.75, and 2.0 h, respectively, when 60 mg/kg S. miltiorrhiza Depside salts were administrated. The areas under the curve for LSB, RA, and LA were 51.6, 6.6, and 25.2 mg . h/l, respectively, and the values decreased in the individual tissues in the following order: kidney > lung > liver > heart > spleen > brain for LSB; kidney > lung > heart > liver > spleen > brain for RA; and heart > lung > kidney > liver > spleen > brain for LA. After intravenous administration of 60 mg/kg S. miltiorrhiza Depside salts, 86% of the LSB was excreted in the bile within 6 h. The main metabolites M1 and M2 were found in the serum. Overall, the results show that Depside salts from S. miltiorrhiza are rapidly and widely distributed to tissues after intravenous administration in rats but that they are also rapidly cleared and excreted.
Haijun Zhang - One of the best experts on this subject based on the ideXlab platform.
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salvianolic acid i a new Depside from salvia cavaleriei
Planta Medica, 1994Co-Authors: Haijun ZhangAbstract:Abstract A new Depside named salvianolic acid I was isolated from the aqueous extract of SALVIA CAVALERIEI, along with salvianolic acids A, B, C, H, isosalvianolic acid C, lithospermic acid, and rosmarinic acid. The chemical struktures were determined by spectral analysis. Two methylated caffeic acid dimers were synthesized using ferulic acid as the starting material.