Ferulic acid(FA) is an active component of herbal medicines. One of the best documented activities of FA is its antioxidant property. Moreover, FA exerts antiallergic, anti-inflammatory, and hepatoprotective effects. ...Ferulic acid(FA) is an active component of herbal medicines. One of the best documented activities of FA is its antioxidant property. Moreover, FA exerts antiallergic, anti-inflammatory, and hepatoprotective effects. However, the metabolic pathways of FA in humans remain unclear. To identify whether human CYP or UGT enzymes are involved in the metabolism of FA, reaction phenotyping of FA was conducted using major CYP-selective chemical inhibitors together with individual CYP and UGT Supersomes. The CYPand/or UGT-mediated metabolism kinetics were examined simultaneously or individually. Relative activity factor and total normalized rate approaches were used to assess the relative contributions of each major human CYPs towards the FA metabolism. Incubations of FA with human liver microsomes(HLM) displayed NADPH-and UDPGA-dependent metabolism with multiple CYP and UGT isoforms involved. CYPs and UGTs contributed equally to the metabolism of FA in HLM. Although CYP1 A2 and CYP3 A4 appeared to be the major contributors in the CYP-mediated clearance, their contributions to the overall clearance are still minor(< 25%). As a constitute of many food and herbs, FA poses low drug-drug interaction risk when co-administrated with other herbs or conventional medicines because multiple phase I and phase II enzymes are involved in its metabolism.展开更多
Objective:To relate physiologic changes and presence of illnesses in older adults,with the risk of appearance of adverse reactions and pharmacological interactions as consequence of the use of medicinal plants.Methods...Objective:To relate physiologic changes and presence of illnesses in older adults,with the risk of appearance of adverse reactions and pharmacological interactions as consequence of the use of medicinal plants.Methods:To carry out a search in the last 5 years and to present a general vision about what have been published related to the use of medicinal plants with risk of appearance of adverse reactions and interactions in older adults.Conclusions:Technological prevision based on the search of articles in the Virtual Library in Health(BVS)and using the words key“medicinal plants”,“older adult”,“pharmacokinetics”,“adverse reactions”,“elderly”,“pharmacological interactions”,and the association among them.展开更多
The eme reactions of α-ionones with singlet oxygen were examined to ascertain the effect of secondary Me interaction between the reactants on the reaction regiospecificity. Exclusive formation of 3-hydroxy-γ-ionones...The eme reactions of α-ionones with singlet oxygen were examined to ascertain the effect of secondary Me interaction between the reactants on the reaction regiospecificity. Exclusive formation of 3-hydroxy-γ-ionones found in the reactions reveals favorable interaction of singlet oxygen with the acyclic α-hydrogen atom,On the other hand,no formation of 3-hy- droxy-β-ionones implies that the steric requirement was not met for the bond formation between zwitterionic perepoxide with C_1-hydrogen in the process.The MMP21 and MNDO calculations indicate minus value of the secondary interaction energy for the aeyelie α-hydrogen abstrac- tion and a repulsion between the oxygen with C_1-hydrogen atom.Twisting tilting of the double bond may account for favorable attack of singlet oxygen on C_3.An explanation of the excellent regiospecificity was addressed and placed in proper mechanic prospective.展开更多
As an advanced and new technology in molecular simulation fields, ReaxFF reactive force field has been developed and widely applied during the last two decades. ReaxFF bridges the gap between quantum chemistry （QC） ...As an advanced and new technology in molecular simulation fields, ReaxFF reactive force field has been developed and widely applied during the last two decades. ReaxFF bridges the gap between quantum chemistry （QC） and non-reactive empirical force field based molecular simulation methods, and aims to provide a transferable potential which can describe many chemical reactions with bond formation and breaking. This review presents an overview of the development and applications of ReaxFF reactive force field in the fields of reaction processes, biology and materials, including （1） the mechanism studies of organic reactions under extreme conditions （like high temperatures and pressures） related with high-energy materials, hydrocarbons and coals, （2） the structural properties ofnanomaterials such as graphene oxides, carbon nanotubes, silicon nanowires and metal nanoparticles, （3） interfacial interactions of solid-solid, solid-liquid and biological/inorganic surfaces, （4） the catalytic mechanisms of many types of metals and metal oxides, and （5） electrochemical mechanisms of fuel cells and lithium batteries. The limitations and challenges of ReaxFF reactive force field are also mentioned in this review, which will shed light on its future applications to a wider range of chemical environments.展开更多
基金supported by Chinese National Science & Technology Major Special Project on Major New Drug Innovation(Nos.2008ZXJ09006001 and 2015ZX09J15104)National Natural Science Foundation of China(No.81130067)
文摘Ferulic acid(FA) is an active component of herbal medicines. One of the best documented activities of FA is its antioxidant property. Moreover, FA exerts antiallergic, anti-inflammatory, and hepatoprotective effects. However, the metabolic pathways of FA in humans remain unclear. To identify whether human CYP or UGT enzymes are involved in the metabolism of FA, reaction phenotyping of FA was conducted using major CYP-selective chemical inhibitors together with individual CYP and UGT Supersomes. The CYPand/or UGT-mediated metabolism kinetics were examined simultaneously or individually. Relative activity factor and total normalized rate approaches were used to assess the relative contributions of each major human CYPs towards the FA metabolism. Incubations of FA with human liver microsomes(HLM) displayed NADPH-and UDPGA-dependent metabolism with multiple CYP and UGT isoforms involved. CYPs and UGTs contributed equally to the metabolism of FA in HLM. Although CYP1 A2 and CYP3 A4 appeared to be the major contributors in the CYP-mediated clearance, their contributions to the overall clearance are still minor(< 25%). As a constitute of many food and herbs, FA poses low drug-drug interaction risk when co-administrated with other herbs or conventional medicines because multiple phase I and phase II enzymes are involved in its metabolism.
文摘Objective:To relate physiologic changes and presence of illnesses in older adults,with the risk of appearance of adverse reactions and pharmacological interactions as consequence of the use of medicinal plants.Methods:To carry out a search in the last 5 years and to present a general vision about what have been published related to the use of medicinal plants with risk of appearance of adverse reactions and interactions in older adults.Conclusions:Technological prevision based on the search of articles in the Virtual Library in Health(BVS)and using the words key“medicinal plants”,“older adult”,“pharmacokinetics”,“adverse reactions”,“elderly”,“pharmacological interactions”,and the association among them.
基金project supported by the National Natural Science Foundation of China.
文摘The eme reactions of α-ionones with singlet oxygen were examined to ascertain the effect of secondary Me interaction between the reactants on the reaction regiospecificity. Exclusive formation of 3-hydroxy-γ-ionones found in the reactions reveals favorable interaction of singlet oxygen with the acyclic α-hydrogen atom,On the other hand,no formation of 3-hy- droxy-β-ionones implies that the steric requirement was not met for the bond formation between zwitterionic perepoxide with C_1-hydrogen in the process.The MMP21 and MNDO calculations indicate minus value of the secondary interaction energy for the aeyelie α-hydrogen abstrac- tion and a repulsion between the oxygen with C_1-hydrogen atom.Twisting tilting of the double bond may account for favorable attack of singlet oxygen on C_3.An explanation of the excellent regiospecificity was addressed and placed in proper mechanic prospective.
文摘As an advanced and new technology in molecular simulation fields, ReaxFF reactive force field has been developed and widely applied during the last two decades. ReaxFF bridges the gap between quantum chemistry （QC） and non-reactive empirical force field based molecular simulation methods, and aims to provide a transferable potential which can describe many chemical reactions with bond formation and breaking. This review presents an overview of the development and applications of ReaxFF reactive force field in the fields of reaction processes, biology and materials, including （1） the mechanism studies of organic reactions under extreme conditions （like high temperatures and pressures） related with high-energy materials, hydrocarbons and coals, （2） the structural properties ofnanomaterials such as graphene oxides, carbon nanotubes, silicon nanowires and metal nanoparticles, （3） interfacial interactions of solid-solid, solid-liquid and biological/inorganic surfaces, （4） the catalytic mechanisms of many types of metals and metal oxides, and （5） electrochemical mechanisms of fuel cells and lithium batteries. The limitations and challenges of ReaxFF reactive force field are also mentioned in this review, which will shed light on its future applications to a wider range of chemical environments.
