Lipoprotein（a） [Lp（a）] is composed of a low density lipoprotein（LDL）-like particle to which apolipoprotein（a）[apo（a）] is linked by a single disulfide bridge. Lp（a） is considered a causal risk factor for is...Lipoprotein（a） [Lp（a）] is composed of a low density lipoprotein（LDL）-like particle to which apolipoprotein（a）[apo（a）] is linked by a single disulfide bridge. Lp（a） is considered a causal risk factor for ischemic cardiovascular disease（CVD） and calcific aortic valve stenosis（CAVS）. The evidence for a causal role of Lp（a） in CVD and CAVS is based on data from large epidemiological databases, mendelian randomization studies, and genome-wide association studies. Despite the well-established role of Lp（a） as a causal risk factor for CVD and CAVS, the underlying mechanisms are not well understood. A key role in the Lp（a） functionality may be played by its oxidized phospholipids（OxPL） content. Importantly, most of circulating OxPL are associated with Lp（a）; however, the underlying mechanisms leading to this preferential sequestration of OxPL on Lp（a） over the other lipoproteins,are mostly unknown. Several studies support the hypothesis that the risk of Lp（a） is primarily driven by its OxPL content.An important role in Lp（a） functionality may be played by the lipoprotein-associated phospholipase A_2（Lp-PLA_2）,an enzyme that catalyzes the degradation of OxPL and is bound to plasma lipoproteins including Lp（a）. The present review article discusses new data on the pathophysiological role of Lp（a） and particularly focuses on the functional role of OxPL and Lp-PLA_2 associated with Lp（a）.展开更多
Acute fulminant pancreatitis was produced in dogs by injection of autobile into the mainpancreatic duct.After injection the phospholipase A<sub>2</sub>（PLA<sub>2</sub>）activities in serum,lun...Acute fulminant pancreatitis was produced in dogs by injection of autobile into the mainpancreatic duct.After injection the phospholipase A<sub>2</sub>（PLA<sub>2</sub>）activities in serum,lung lymph andbronchoalveolar lavage fluid（BAL）were elevated significantly,lung lymph flow and pulmonarytransvascular potein clearance increased progressively,protein content and cell numbers in BAL inthe experimental animals were significantly higher than those in the control animals.Furthermore thelung index,wet to dry lung weight ratio,extravascular lung water to bloodless dry lung weight ra-tio,extravascuar lung water to bloodless dry lung weight ratio increased significantly as comparedto control animals.Pretreatment with PLA<sub>2</sub> inhibitor,chloroquine,blocked the changes mentionedabove.This experiment suggests:1.PLA<sub>2</sub> activity in lung lymph fluid as well as in serum andBAL is elevated in acute hemorrhagic pancreatitis.2.Elevated PLA<sub>2</sub> activity may increase thepulmonary vascular permeability.3.PLA<sub>2</sub> is the major factor leading to pulmonary edema in acutehemorrhagic pancreatitis.4.Phagocytes contribute to the lung injury induced by PLA<sub>2</sub> to some ex-tent.展开更多
Objective: To imastigate the effects of anisodamine on pulmonary α1- adrenergic receptor andphospholipase A, in acute lung injurg. Methods: Change of α1--adrenergic receptor (al AR ) in lung tissllesduring endotoxin...Objective: To imastigate the effects of anisodamine on pulmonary α1- adrenergic receptor andphospholipase A, in acute lung injurg. Methods: Change of α1--adrenergic receptor (al AR ) in lung tissllesduring endotoxin--induced rat acute lung injury was measured with radioligand biding assay. The effects ofanisodamine on pulmonary α1--AR and phospholipase A2 (PLA2 ) were observed. Results: 1. 4 h after theendotoxin injection, there was a significant decrease in the maximal binding capacity of α1--AR by 34% ascompared with the control group. meanwhile elevated activity of PLA2 in rat lung and reduction of thephospholipids content of cell membrane was found. 2. Anisodamine could attenuate endotoxin--induced acutelung injury in rats. Conclusion: This effect might be related to anisodamine’s blockage of α1--AR andsuppression of PLA2, prevention of membranous phospholipids from degradation. and the reduction ofarachidonic acid release.展开更多
Bee venom phospholipase A2(BvPLA2) is a lipolytic enzyme that catalyzes the hydrolysis of the sn-2 acyl bond of glycerophospholipids to liberate free fatty acids and lysophospholipids.In this work,a new BvPLA2(AccPLA2...Bee venom phospholipase A2(BvPLA2) is a lipolytic enzyme that catalyzes the hydrolysis of the sn-2 acyl bond of glycerophospholipids to liberate free fatty acids and lysophospholipids.In this work,a new BvPLA2(AccPLA2) gene from the Chinese honeybee(Apis cerana cerana) venom glands was inserted into bacmid to construct a recombinant transfer vector.Tn-5B-4(Tn) cells were transfected with the recombinant bacmid DNA for expression.Sodium dodecylsulfate-polyacrylamide gel electrophoresis(SDS-PAGE) analysis revealed a double band with molecular weights of 16 and 18 kDa.Products of hexahistidine AccPLA2 fusion protein accumulated up to 5.32% of the total cellular proteins.The AccPLA2 fusion protein was cross reactive with the anti-AmPLA2(BvPLA2 of the European honeybee,Apis mellifera) polyclonal serum.The reaction resulted in a double glycosylation band,which agrees with the band generated by the native AmPLA2 in Western blot analysis.The PLA2 activity of the total extracted cellular protein in the hydrolyzing egg yolk is about 3.16 μmol/(min·mg).In summary,the recombinant AccPLA2 protein,a native BvPLA2-like structure with corresponding biological activities,can be glycosylated in Tn cells.These findings provided fundamental knowledge for potential genetic engineering to produce AccPLA2 in the pharmaceutical industry.展开更多
Basic phospholipase A2 (BPLA2) from the venom of Agkistrodon halys pallas has a strong ability to hemolyze erythrocytes. The asymmetrical unit of P212121 crystal of BPLA2 contains two molecules. Self-rotation function...Basic phospholipase A2 (BPLA2) from the venom of Agkistrodon halys pallas has a strong ability to hemolyze erythrocytes. The asymmetrical unit of P212121 crystal of BPLA2 contains two molecules. Self-rotation function was used to study the orientation relationship of these two molecules. Cross-rotation and translation functions were then used to determine the orientations and positions of the two molecules in the unit cell. The model building and preliminary structure refinement were carried out. The result shows that the two molecules in the asymmetrical unit of orthorhombic crystal are related by a non-crystallographic 2-fold symmetry axis.展开更多
Agkistrodotoxin, a neutral phospholipase A2 with high presynaptic neurotoxicity from the venom of Agkistrodon halys Pallas, has been crystallized by hanging drop vapor diffusion method. The crystal belongs to P21 spac...Agkistrodotoxin, a neutral phospholipase A2 with high presynaptic neurotoxicity from the venom of Agkistrodon halys Pallas, has been crystallized by hanging drop vapor diffusion method. The crystal belongs to P21 space group with the cell dimensions a = 10.836 nm, b=8.486nm, c = 7.082nm, β=109.87$ showing C2 pseu-do-symmetry. Diffraction data to 0. 26 nm resolution have been collected on a Siemens X-200B area detector. C2 pseu-do-symmetry suggests that there exists a non-crystallographic two-fold axis parallel to crystallographic b axis. Self-rotation function calculation with different integrated radius and resolution ranges using the program POLARRFN yields four stable high peaks corresponding to three more non-crystallographic two-fold axis and one special non-crystal-lographic symmetry. The molecules in the asymmetric unit are suggested to be arranged in a manner of "dimer of dimers" by inference.展开更多
Central nervous system(CNS)trauma,including traumatic brain injury and spinal cord injury,has a high rate of disability and mortality,and effective treatment is currently lacking.Previous studies have revealed that ne...Central nervous system(CNS)trauma,including traumatic brain injury and spinal cord injury,has a high rate of disability and mortality,and effective treatment is currently lacking.Previous studies have revealed that neural inflammation plays a vital role in CNS trauma.As the initial enzyme in neuroinflammation,cytosolic phospholipase A_(2)(cPLA2)can hydrolyze membranous phosphatides at the sn-2 position in a preferential way to release lysophospholipids andω3-polyunsaturated fatty acid dominated by arachidonic acid,thereby inducing secondary injuries.Although there is substantial fresh knowledge pertaining to cPLA2,in-depth comprehension of how cPLA2 participates in CNS trauma and the potential methods to amelio rate the clinical res ults after CNS trauma are still insufficient.The present review summarizes the latest understanding of how cPLA2 participates in CNS trauma,highlighting novel findings pertaining to how cPLA2 activation initiates the potential mechanisms specifically,neuroinflammation,lysosome membrane functions,and autophagy activity,that damage the CNS after trauma.Moreover,we focused on testing a variety of drugs capable of inhibiting cPLA2 or the upstream pathway,and we explored how those agents might be utilized as treatments to improve the results following CNS trauma.This review aimed to effectively understand the mechanism of cPLA2 activation and its role in the pathophysiological processes of CNS trauma and provide clarification and a new referential framework for future research.展开更多
文摘Lipoprotein（a） [Lp（a）] is composed of a low density lipoprotein（LDL）-like particle to which apolipoprotein（a）[apo（a）] is linked by a single disulfide bridge. Lp（a） is considered a causal risk factor for ischemic cardiovascular disease（CVD） and calcific aortic valve stenosis（CAVS）. The evidence for a causal role of Lp（a） in CVD and CAVS is based on data from large epidemiological databases, mendelian randomization studies, and genome-wide association studies. Despite the well-established role of Lp（a） as a causal risk factor for CVD and CAVS, the underlying mechanisms are not well understood. A key role in the Lp（a） functionality may be played by its oxidized phospholipids（OxPL） content. Importantly, most of circulating OxPL are associated with Lp（a）; however, the underlying mechanisms leading to this preferential sequestration of OxPL on Lp（a） over the other lipoproteins,are mostly unknown. Several studies support the hypothesis that the risk of Lp（a） is primarily driven by its OxPL content.An important role in Lp（a） functionality may be played by the lipoprotein-associated phospholipase A_2（Lp-PLA_2）,an enzyme that catalyzes the degradation of OxPL and is bound to plasma lipoproteins including Lp（a）. The present review article discusses new data on the pathophysiological role of Lp（a） and particularly focuses on the functional role of OxPL and Lp-PLA_2 associated with Lp（a）.
文摘Acute fulminant pancreatitis was produced in dogs by injection of autobile into the mainpancreatic duct.After injection the phospholipase A<sub>2</sub>（PLA<sub>2</sub>）activities in serum,lung lymph andbronchoalveolar lavage fluid（BAL）were elevated significantly,lung lymph flow and pulmonarytransvascular potein clearance increased progressively,protein content and cell numbers in BAL inthe experimental animals were significantly higher than those in the control animals.Furthermore thelung index,wet to dry lung weight ratio,extravascular lung water to bloodless dry lung weight ra-tio,extravascuar lung water to bloodless dry lung weight ratio increased significantly as comparedto control animals.Pretreatment with PLA<sub>2</sub> inhibitor,chloroquine,blocked the changes mentionedabove.This experiment suggests:1.PLA<sub>2</sub> activity in lung lymph fluid as well as in serum andBAL is elevated in acute hemorrhagic pancreatitis.2.Elevated PLA<sub>2</sub> activity may increase thepulmonary vascular permeability.3.PLA<sub>2</sub> is the major factor leading to pulmonary edema in acutehemorrhagic pancreatitis.4.Phagocytes contribute to the lung injury induced by PLA<sub>2</sub> to some ex-tent.
文摘Objective: To imastigate the effects of anisodamine on pulmonary α1- adrenergic receptor andphospholipase A, in acute lung injurg. Methods: Change of α1--adrenergic receptor (al AR ) in lung tissllesduring endotoxin--induced rat acute lung injury was measured with radioligand biding assay. The effects ofanisodamine on pulmonary α1--AR and phospholipase A2 (PLA2 ) were observed. Results: 1. 4 h after theendotoxin injection, there was a significant decrease in the maximal binding capacity of α1--AR by 34% ascompared with the control group. meanwhile elevated activity of PLA2 in rat lung and reduction of thephospholipids content of cell membrane was found. 2. Anisodamine could attenuate endotoxin--induced acutelung injury in rats. Conclusion: This effect might be related to anisodamine’s blockage of α1--AR andsuppression of PLA2, prevention of membranous phospholipids from degradation. and the reduction ofarachidonic acid release.
基金Project (No 2007AA10Z324) supported by the National High-Tech Research and Development Program (863) of China
文摘Bee venom phospholipase A2(BvPLA2) is a lipolytic enzyme that catalyzes the hydrolysis of the sn-2 acyl bond of glycerophospholipids to liberate free fatty acids and lysophospholipids.In this work,a new BvPLA2(AccPLA2) gene from the Chinese honeybee(Apis cerana cerana) venom glands was inserted into bacmid to construct a recombinant transfer vector.Tn-5B-4(Tn) cells were transfected with the recombinant bacmid DNA for expression.Sodium dodecylsulfate-polyacrylamide gel electrophoresis(SDS-PAGE) analysis revealed a double band with molecular weights of 16 and 18 kDa.Products of hexahistidine AccPLA2 fusion protein accumulated up to 5.32% of the total cellular proteins.The AccPLA2 fusion protein was cross reactive with the anti-AmPLA2(BvPLA2 of the European honeybee,Apis mellifera) polyclonal serum.The reaction resulted in a double glycosylation band,which agrees with the band generated by the native AmPLA2 in Western blot analysis.The PLA2 activity of the total extracted cellular protein in the hydrolyzing egg yolk is about 3.16 μmol/(min·mg).In summary,the recombinant AccPLA2 protein,a native BvPLA2-like structure with corresponding biological activities,can be glycosylated in Tn cells.These findings provided fundamental knowledge for potential genetic engineering to produce AccPLA2 in the pharmaceutical industry.
基金Project supported by Chinese Academy of Sciences.
文摘Basic phospholipase A2 (BPLA2) from the venom of Agkistrodon halys pallas has a strong ability to hemolyze erythrocytes. The asymmetrical unit of P212121 crystal of BPLA2 contains two molecules. Self-rotation function was used to study the orientation relationship of these two molecules. Cross-rotation and translation functions were then used to determine the orientations and positions of the two molecules in the unit cell. The model building and preliminary structure refinement were carried out. The result shows that the two molecules in the asymmetrical unit of orthorhombic crystal are related by a non-crystallographic 2-fold symmetry axis.
基金Project supported by the Chinese Academy of Sciences.
文摘Agkistrodotoxin, a neutral phospholipase A2 with high presynaptic neurotoxicity from the venom of Agkistrodon halys Pallas, has been crystallized by hanging drop vapor diffusion method. The crystal belongs to P21 space group with the cell dimensions a = 10.836 nm, b=8.486nm, c = 7.082nm, β=109.87$ showing C2 pseu-do-symmetry. Diffraction data to 0. 26 nm resolution have been collected on a Siemens X-200B area detector. C2 pseu-do-symmetry suggests that there exists a non-crystallographic two-fold axis parallel to crystallographic b axis. Self-rotation function calculation with different integrated radius and resolution ranges using the program POLARRFN yields four stable high peaks corresponding to three more non-crystallographic two-fold axis and one special non-crystal-lographic symmetry. The molecules in the asymmetric unit are suggested to be arranged in a manner of "dimer of dimers" by inference.
基金supported by the National Natural Science Foundation of China,No.82072192(to KLZ)Public Welfare Technology Research Project of Zhejiang Province,No.LGF20H150003(to KLZ)+1 种基金the Natural Science Foundation of Zhejiang Province,Nos.LY17H060009 and Y21H060050(both to WFN)Wenzhou Science and Technology Bureau Foundation,No.Y20210438(to KLZ)。
文摘Central nervous system(CNS)trauma,including traumatic brain injury and spinal cord injury,has a high rate of disability and mortality,and effective treatment is currently lacking.Previous studies have revealed that neural inflammation plays a vital role in CNS trauma.As the initial enzyme in neuroinflammation,cytosolic phospholipase A_(2)(cPLA2)can hydrolyze membranous phosphatides at the sn-2 position in a preferential way to release lysophospholipids andω3-polyunsaturated fatty acid dominated by arachidonic acid,thereby inducing secondary injuries.Although there is substantial fresh knowledge pertaining to cPLA2,in-depth comprehension of how cPLA2 participates in CNS trauma and the potential methods to amelio rate the clinical res ults after CNS trauma are still insufficient.The present review summarizes the latest understanding of how cPLA2 participates in CNS trauma,highlighting novel findings pertaining to how cPLA2 activation initiates the potential mechanisms specifically,neuroinflammation,lysosome membrane functions,and autophagy activity,that damage the CNS after trauma.Moreover,we focused on testing a variety of drugs capable of inhibiting cPLA2 or the upstream pathway,and we explored how those agents might be utilized as treatments to improve the results following CNS trauma.This review aimed to effectively understand the mechanism of cPLA2 activation and its role in the pathophysiological processes of CNS trauma and provide clarification and a new referential framework for future research.
