Helminthic cysteine proteases are well known to play critical roles in tissue invasion, nutrient uptake, and immune evasion of the parasites. In the same manner, the sparganum, the plerocercoid of Spirometra mansoni, is also known to secrete a large amount of cysteine proteases. However, cysteine protease inhibitors regulating the proteolytic activities of the cysteine protease are poorly illustrated. In this regard, we partially purified an endogenous cysteine protease inhibitor from spargana and characterized its biochemical properties. The cysteine protease inhibitor was purified by sequential chromatographies using Resource Q anion exchanger and Superdex 200 HR gel filtration from crude extracts of spargana. The molecular weight of the purified protein was estimated to be about 11 kD on SDS-PAGE. It was able to inhibit papain and 27 kDa cysteine protease of spargana with the ratio of 25.7% and 49.1%, respectively, while did not inhibit chymotrypsin. This finding suggests that the cysteine protease inhibitor of spargana may be involved in regulation of endogenous cysteine proteases of the parasite, rather than interact with cysteine proteases from their hosts.
Animals ; Cystatins/pharmacology ; Cysteine Endopeptidases/metabolism ; Cysteine Proteinase Inhibitors/chemistry/*metabolism/*pharmacology ; Helminth Proteins/*metabolism/*pharmacology ; Spirometra/*metabolism

OBJECTIVETo study the factors influencing the activity of fibrinolytic enzymes from earthworm and to obtain the better way to extract fibrinolytic enzymes as well as keep its optimum activity.

METHOD75% alcohol, 0.9% NaCl and 10% saccharose was used to extract the crude fibrinolytic enzymes from earthworm, the method of urokinase gelose-fibrin plate was used to measure the activity of fibrinolytic enzymes from earthworm. and the method of 3,3'-diaminobezidine tetrahydrochloride colorimetry to was used measure the content of selenium. The method use ts of measuring the content of arsenic was silver diethyldithiocarbamate colorimetry.

RESULTThe fibrinolytin of earthworms reared with cattle soils had higher activity than that reared with garbage. The arsenic in the earthworm's body could improve the activity of earthworm's fibrinolytin. However, the selenium had litter influence on it. Among the three methods of extraction, the 75% alcohol one was the most efficient, the 0.9% NaCl was next, and the 10% saccharose was the lowest. The influence of dialysis on the activity of fibrinolytin was less than that of ultrafiltration, when the earthworm's fibrinolytin enzyme was further sublimated.

CONCLUSIONThe activity of the earthworm's fibrinolytin will be increased earthworm is reared with the fitting baits and when appropriate methods, of extraction and purification are used.

Animal Feed ; Animals ; Endopeptidases ; isolation & purification ; metabolism ; Oligochaeta ; chemistry ; Selenium ; pharmacology

Drug Resistance, Viral ; Endopeptidases ; Hepatitis B virus ; drug effects ; Hepatitis B, Chronic ; virology ; Humans ; Interferons ; pharmacology

In this paper,metabolomics and network pharmacology were used to investigate the bioactive components of Harrisonia perforata and their possible mechanisms of action. Metabolites in the flowers,fruits,branches,leaves and stalks of H. perforata were analyzed by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. Meanwhile,multiple statistical analysis methods including principal component analysis( PCA) and orthogonal partial least squares discriminant analysis( OPLS-DA)were applied to screen and identify differential compounds. With metabolomics method,9 differential compounds were preliminarily identified from leaves and other non-traditional medicinal parts. Subsequently,these compounds were explored by using network pharmacology. With gastrointestinal absorption and drug-likeness as limiting conditions,they were imported into the Swiss ADME,from which 7 compounds with potential medicinal activity were obtained. Then,their targets were predicted by PharmMapper,with Human Protein Targets Only and Normalized Fit Score>0. 9 set as limiting conditions,and 60 standardized potential targets were identified with Uniprot. KEGG( Kyoto encyclopedia of genes and genomes) pathway data was obtained using metascape and the " potential active ingredients-target-pathway" network was constructed with Cytoscape 3. 7. 2. The enrichment analysis of KEGG demonstrated that the 60 targets were enriched in 78 signaling pathways( min overlap: 3,P value cutoff: 0. 01,min enrichment: 1. 5),many of which are related to anti-bacteria,anti-inflammation and anti-virus,such as IL-17 signaling pathway,RIG-I-like receptor signaling pathway and NOD-like receptor signaling pathway. Finally,depending on the clinical activity of H. perforata,the relevant signaling pathways were analyzed through experimental data and literature. Dehydroconiferyl alcohol was reported to have the anti-inflammatory effect and perforamone D to possess the antimycobacterial activity. The KEGG pathway enrichment analysis showed that dehydroconiferyl alcohol could act on the Alzheimer's disease( AD) signaling pathway by targeting CDK5 R1 and BACE1. ACh E inhibitor is the most promising drug to treat AD,while dehydroconiferyl alcohol has been proved to inhibit ACh E according to literature. The experimental results revealed that the extract of leaves of H. perforata can effectively inhibit the growth of Staphylococcus aureus. These are consistent with the enrichment analysis results of KEGG. This study explored the bioactive components and pharmacodynamics of the leaves of the H. perforata,laying a theoretical foundation for its in-depth development and rational application.
Amyloid Precursor Protein Secretases ; Aspartic Acid Endopeptidases ; Drugs, Chinese Herbal/pharmacology* ; Humans ; Metabolomics ; Simaroubaceae

OBJECTIVETo investigate the heterozygous genotype and molecular characteristics of Organophosphorus resistance associated with heterozygous Estbeta2 of esterase B2 gene from natural population of Culex pipiens complex.

METHODSGenomic DNA was extracted from natural populations of Culex pipiens complex in Hangzhou. The PCR-restriction fragment length polymorphism (PCR-RFLP) assay was applied to type the resistance associated esterase gene. Estbeta2 of esterase B2 gene was identified by PCR-RFLP, and the genotyping for heterozygous Estbeta2 was carried out after restriction enzyme digesting by Bfm I endonuclease.

RESULTSThe DNA was isolated from 207 Culex pipiens respectively, while 156 PCR samples showed positive and the positive rate was 75.36% (156/207). The PCR-RFLP assay of esterase B2 gene revealed that the Estbeta2 was accounted about 28.20% (44/156) in 156 positive samples. There were two genotypes identified, namely homozygous Estbeta2 (90.90%, 30/33) and heterozygous Estbeta2 (9%, 3/33), heterozygous Estbeta2 was in existence of a hybrid form as which combined with Estbeta2 and a subtype (Estbeta2/Estbeta2(1)).

CONCLUSIONHeterozygous Estbeta2 of Organophosphorus resistance associated with esterase genotype was determined in natural population of Culex pipiens, and a genotyping method was established.

Animals ; Culex ; enzymology ; genetics ; Genes, Insect ; Genotype ; Heterozygote ; Insecticide Resistance ; genetics ; Insecticides ; pharmacology ; Organophosphorus Compounds ; pharmacology ; Phenotype ; Serine Endopeptidases ; genetics

AS1. 398 neutral protease was immobilized onto carboxymethyl chitosan with glutaraldehyde as cross-linking agent. The effects of pH, time of cross-linking, amount of cross-linking agent and the ratio of enzyme to carrier on the activity of the immobilized enzyme were demonstrated, and the optimum immobilization condition of AS1. 398 neutral protease was established. Also studied was the characterization of immobilized enzyme,including pH, temperature, Km and the stability of storage.
Bacterial Proteins ; chemistry ; Chitosan ; analogs & derivatives ; pharmacology ; Endopeptidases ; chemistry ; Enzymes, Immobilized ; chemical synthesis ; chemistry ; Glutaral ; pharmacology ; Microspheres

In a 5L fermentor the production conditions of alkaline protease gene engineering strain BA071 were investigated. The maximum activity of alkaline protease reached 24,480 u/mL in 40 hours of fermentation by combination of enhancing aeration and changing the agitation rate. The fast purification method of recombinant protease was conducted with FPLC (Fast Protein Liquid Chromatography). The crude enzyme, treated with ammonium sulfate fractionation and decolored with DEAE-A-50 and polyethylene glycol concentration, was purified with CM-Sephadex-C-50 and Sephadex-G-75. The purified enzyme appears homologous on SDS-PAGE. The purity of enzyme was increased 76.2 times. SDS-PAGE analysis showed that the molecular weights of expressed recombinant products were about 28 kD. The optimal reaction pH and temperature of recombinant enzyme were at pH11 and 60 degrees C, respectively. The recombinant enzyme exhibited high temperature tolerance and was stable at a wide range of pH. Ca2+, MG2+ can enhance the stability of the recombinant enzyme. While the protease activity of the enzyme was strongly inhibited by Hg2+, Ag+, PMFS [symbol: see text] DFP, and was not affected by SDS and Urea.
Bacillus ; genetics ; metabolism ; Enzyme Stability ; Fermentation ; Genetic Engineering ; Metals ; pharmacology ; Recombinant Proteins ; biosynthesis ; Serine Endopeptidases ; genetics ; isolation & purification ; metabolism

OBJECTIVETo identify the effect of NEP on Abeta -induced apoptosis in PC12 cells.

METHODSPC12 cells that stably express NEP is generated and the effect of NEP on the process of apoptosis induced by Abeta is analyzed, including the viability of the cells, the production of LDH, ROS and ATP, the activity of Caspase-3.

RESULTSNEP could improve the viability of cells and the production of ATP, inhibit the release of LDH and ROS. In the same time, the activity of caspase-3 descended (P < 0.05). But iNEP had not significant effect on cells apoptosis (P > 0.05).

CONCLUSIONNEP has the protective effect on Abeta-induced apoptosis in PC12 cells.

Amyloid beta-Peptides ; pharmacology ; Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Endopeptidases ; genetics ; metabolism ; PC12 Cells ; Rats ; Transfection

Assisted hatching (AH), which is known to improve the hatching potential of mammalian embryos, has been used to increase the pregnancy rate in in vitro fertilization cycles. However, the effect of AH on a trypsin-like protease, which is known to be associated with the hatching process, has not been studied. In this study, we evaluate whether the intactness of zona pellucida affects the secretion of a trypsin-like protease from mouse blastocyst. Four- to 8-cell stage mouse embryos were collected at 66- to 68 hr after hCG injection and divided into 3 groups according to the manipulation of zona pellucida. The groups are no treatment (control), drilling of zona pellucida (ZD) and thinning of zona pellucida (ZT). The activity of a trypsin-like protease, blastocyst development and hatching rate were compared among the three groups at 110 and 135 hr after hCG injection, respectively. The protease activity and blastocyst development were not significantly different among control, ZD and ZT groups at 110 and 135 hr after hCG injection, respectively. However, the hatching rate of ZD and ZT groups was significantly higher than that of control group at each time, respectively (p>0.001). Even in the zona pellucida removed embryos, the protease activity did not differ from the control group. In conclusion, the secretion of a trypsin-like protease from mouse blastocyst does not seem to be affected by the intactness of zona pellucida.
Animal ; Blastocyst/secretion ; Blastocyst/enzymology* ; Female ; Fertilization in Vitro/methods ; Gonadotropins, Chorionic/pharmacology ; Mice ; Mice, Inbred C57BL ; Mice, Inbred CBA ; Pregnancy ; Serine Endopeptidases/secretion ; Serine Endopeptidases/metabolism* ; Zona Pellucida/physiology* ; Zona Pellucida/drug effects

AIMTo explore the intestinal absorption characteristics of lumbrokinase (YJM-I) in the absence or presence of various absorption enhancers and to find the optimum intestinal site for YJM-I absorption.

METHODSThe absorption kinetics and absorption intestinal sites for YJM-I absorption were investigated with the method of diffusion cell in vitro, duodenum bolus injection, recirculating perfusion and in situ duodenum perfusion in vivo.

RESULTSYJM-I could be transported into blood and kept its biological activity across intestinal endothelial membrane after administration via duodenum site, whereas with lower bioavailability. Some of the absorption enhancers were shown good enhancement effects on intestinal absorption of YJM-I in vitro and in situ experiments. The order of enhanced efficiencies of various enhancers on duodenum, ileum and jejunum in vitro permeation experiments were shown as follows: 1% chitosan > 1% SDCh > 1% Na2EDTA > 1% SDS > 1% sodium caprylate > 1% poloxamer > 1% HP-beta-CD. The order of enhanced efficiencies of various enhancers on duodenum absorption of YJM-I in vivo were as follows: 2.5% SDCh > 2.5% Na2EDTA > 2.0% chitosan > 2.5% SDS > 2.5% sodium caprylate > 2.5% Poloxamer > 2.5% HP-beta-CD.

CONCLUSIONThe results indicated that the absorption of YJM-I could be enhanced by various enhancers, and duodenum was the optimum absorption site of YJM-I. Furthermore, bio-adhesive chitosan might be a potential enhancer of intestinal YJM-I absorption.

Administration, Oral ; Animals ; Area Under Curve ; Caprylates ; pharmacology ; Chitosan ; pharmacology ; Deoxycholic Acid ; pharmacology ; Duodenum ; drug effects ; metabolism ; Edetic Acid ; pharmacology ; Endopeptidases ; administration & dosage ; pharmacokinetics ; Injections, Intravenous ; Intestinal Absorption ; Male ; Metabolic Clearance Rate ; Poloxamer ; pharmacology ; Rats ; Rats, Sprague-Dawley