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1.
Life Sci ; 264: 118641, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33148420

RESUMO

Pancreatitis is an inflammatory disease of the pancreas characterized by acinar cell injury and is associated with the abnormal release of trypsin, which results in high mortality due to systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS). The inflammatory response, impaired autophagic flux, endoplasmic reticulum stress (ERS) and their interactions are involved in the development of pancreatitis. Molecular hydrogen (H2) is a novel antioxidant that possesses the features of selective scavenging of oxygen free radicals and nontoxic metabolites and has been shown to be efficacious for treating infection, injury, tumors, ischemia-reperfusion organ injury, metabolic disease and several other diseases. Recent studies have found that H2 is also useful in the treatment of pancreatitis, which may be related to the mechanism of antioxidative stress, anti-inflammation, anti-apoptosis, regulation of immunity and regulation of molecular pathways. This review focuses on the pathogenesis of pancreatitis and the research progress and potential mechanisms of H2 against pancreatitis to provide theoretical bases for future research and clinical application of H2 therapy for pancreatitis.


Assuntos
Hidrogênio/uso terapêutico , Pancreatite/terapia , Animais , Antioxidantes/metabolismo , Apoptose , Autofagia/efeitos dos fármacos , Morte Celular , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Inflamação , Sistema de Sinalização das MAP Quinases , Insuficiência de Múltiplos Órgãos , Estresse Oxidativo , Pâncreas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão , Síndrome de Resposta Inflamatória Sistêmica/metabolismo , Tripsina/química
2.
Food Chem ; 340: 127876, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32871354

RESUMO

Jackfruit is a sweet tropical fruit with very pleasant aroma, and the ripe seeds are edible. In this study, jackfruit seed proteins were isolated and subjected to trypsin digestion. The resultant protein hydrolysate was then subjected to antioxidant assay-guided purification, using centrifugal filtration, C18 reverse-phase and strong cation exchange (SCX) fractionations. The purified SCX fraction was further analyzed by de novo peptide sequencing, and two peptide sequences were identified and synthesized. Peptide JFS-2 (VGPWQK) was detected with antioxidant potential, with EC50 value comparable to that of commercial GSH antioxidant peptide. Additionally, the identified peptides were tested with protein protection potential, in an albumin protein denaturation inhibitory assay. Concurrently, we also investigated the pH, temperature, and gastrointestinal-digestion stability profiles for the identified peptide. With further research efforts, the identified peptides could potentially be developed into preservative agent for protein-rich food systems or as health-promoting diet supplements.


Assuntos
Antioxidantes/análise , Artocarpus/química , Peptídeos/análise , Peptídeos/química , Hidrolisados de Proteína/química , Sementes/química , Antioxidantes/química , Cromatografia por Troca Iônica , Digestão , Conservantes de Alimentos , Concentração de Íons de Hidrogênio , Peptídeos/metabolismo , Temperatura , Tripsina
3.
J Chromatogr A ; 1635: 461742, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33254000

RESUMO

Fast and highly efficient digestion of proteins is essential for high-throughput proteomic analysis. Herein, a facile approach was developed for self-assembly preparation of trypsin-immobilized capillary monolithic column and its application as an immobilized enzyme microreactor (IMER) for fast and highly efficient proteolysis was described. The performance of the trypsin-immobilized monolithic enzyme microreactor was evaluated by in-situ digestion of model proteins. The results showed that the trypsin-immobilized monolithic enzyme microreactor had much higher tryptic digestion efficiency than the free trypsin in solution, where the coverage of peptide sequences by mass spectrometry (MS)-based analysis could bear comparison with the free one, while the digestion time was dramatically shortened from 12 h to 16 s. Furthermore, the trypsin-immobilized monolithic enzyme microreactor also exhibited good practicability to complex human serum sample, in which the total of 45 peptides from human serum albumin (HSA) matched with sequence coverage of 75% were precisely identified. The successful application demonstrated the promising potential of the trypsin-immobilized capillary monolithic column as the IMER in high-throughput proteomic analysis.


Assuntos
Reatores Biológicos , Proteólise , Proteômica/métodos , Tripsina/metabolismo , Proteínas Sanguíneas/metabolismo , Enzimas Imobilizadas/química , Humanos , Espectrometria de Massas , Peptídeos/metabolismo
4.
Food Chem ; 337: 127759, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777568

RESUMO

High-resolution ultrasonic spectroscopy (HR-US) was applied for real-time monitoring of ß-casein hydrolysis by trypsin at various conditions for the first time. The technique is based on the precision measurement of hydration changes proportional to the number of peptide bond hydrolyzed. As HR-US exhibits ultrasonic transparency for most solution, the analysis did not require optical transparency like for 2,4,6-trinitrobenzenesulfonic acid (TNBS) assay. Appropriate enzymatic models were fitted with degree of hydrolysis (dh) profiles to provide kinetic and mechanistic description of proteolysis in terms of initial hydrolysis rate, r0, and rate constant of hydrolysis, kh, and enzyme inactivation, kd. Maximal r0 and dh were obtained at 45 °C and pH 8. The exponential dependence of kinetic parameters allowed determination of the activation (EA = 50.3 ± 7 kJ/mol) and deactivation (ED = 62.23 ± 3 kJ/mol) energies of hydrolysis. The ultrasonic assay provided rapid detection of trypsin activity even at sub-nanomolar concentration.


Assuntos
Caseínas/metabolismo , Ensaios Enzimáticos/métodos , Análise Espectral , Tripsina/metabolismo , Ondas Ultrassônicas , Ativação Enzimática , Hidrólise , Cinética , Proteólise , Soluções
5.
J Vis Exp ; (165)2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33226031

RESUMO

Protein analysis of small numbers of human cells is primarily achieved by targeted proteomics with antibody-based immunoassays, which have inherent limitations (e.g., low multiplex and unavailability of antibodies for new proteins). Mass spectrometry (MS)-based targeted proteomics has emerged as an alternative because it is antibody-free, high multiplex, and has high specificity and quantitation accuracy. Recent advances in MS instrumentation make MS-based targeted proteomics possible for multiplexed quantification of highly abundant proteins in single cells. However, there is a technical challenge for effective processing of single cells with minimal sample loss for MS analysis. To address this issue, we have recently developed a convenient protein carrier-assisted one-pot sample preparation coupled with liquid chromatography (LC) - selected reaction monitoring (SRM) termed cLC-SRM for targeted proteomics analysis of small numbers of human cells. This method capitalizes on using the combined excessive exogenous protein as a carrier and low-volume one-pot processing to greatly reduce surface adsorption losses as well as high-specificity LC-SRM to effectively address the increased dynamic concentration range due to the addition of exogeneous carrier protein. Its utility has been demonstrated by accurate quantification of most moderately abundant proteins in small numbers of cells (e.g., 10-100 cells) and highly abundant proteins in single cells. The easy-to-implement features and no need for specific devices make this method readily accessible to most proteomics laboratories. Herein we have provided a detailed protocol for cLC-SRM analysis of small numbers of human cells including cell sorting, cell lysis and digestion, LC-SRM analysis, and data analysis. Further improvements in detection sensitivity and sample throughput are needed towards targeted single-cell proteomics analysis. We anticipate that cLC-SRM will be broadly applied to biomedical research and systems biology with the potential of facilitating precision medicine.


Assuntos
Proteômica/métodos , Alquilação , Contagem de Células , Fracionamento Celular , Linhagem Celular , Cromatografia Líquida , Análise de Dados , Receptores ErbB/metabolismo , Citometria de Fluxo , Humanos , Sistema de Sinalização das MAP Quinases , Espectrometria de Massas/métodos , Desnaturação Proteica , Tripsina/metabolismo
6.
Sheng Wu Gong Cheng Xue Bao ; 36(11): 2435-2442, 2020 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-33244937

RESUMO

In recent years, mass spectrometry has been widely used to study membrane protein structure and function. However, the application of mass spectrometry to study integral membrane protein is limited because there are many hydrophobic amino acids in the trans-membrane domain of integral membrane protein to cause low sequence coverage detected by LC-MS/MS. Therefore, we used vitamin K epoxide reductase (VKORC1), a human integral membrane protein, as a model to optimize the digestion conditions of chymotrypsin, and developed an in-gel digestion method of chymotrypsin to improve sequence coverage of membrane protein by mass spectrometry. By exploring the effects of calcium concentration, pH value and buffer system on the percentage of sequence coverage, number of total detected and types of unique peptide, and the size of unique peptide, sequence coverage and peptide diversity could be considered under condition of Tris-HCl buffer with 5-10 mmol/L calcium ion concentration and pH value 8.0-8.5. This method could make the sequence coverage of membrane protein to reach more than 80%. It could be widely used in the study of membrane protein structure and function, identification of interaction site between membrane proteins, and identification of binding site between membrane protein and small molecular drug.


Assuntos
Quimotripsina , Proteínas de Membrana , Sequência de Aminoácidos , Cromatografia Líquida , Quimotripsina/metabolismo , Digestão , Humanos , Espectrometria de Massas em Tandem , Tripsina , Vitamina K Epóxido Redutases
7.
Viruses ; 12(10)2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-33003350

RESUMO

The Gammacoronavirus infectious bronchitis virus (IBV) causes a highly contagious and economically important respiratory disease in poultry. In the laboratory, most IBV strains are restricted to replication in ex vivo organ cultures or in ovo and do not replicate in cell culture, making the study of their basic virology difficult. Entry of IBV into cells is facilitated by the large glycoprotein on the surface of the virion, the spike (S) protein, comprised of S1 and S2 subunits. Previous research showed that the S2' cleavage site is responsible for the extended tropism of the IBV Beaudette strain. This study aims to investigate whether protease treatment can extend the tropism of other IBV strains. Here we demonstrate that the addition of exogenous trypsin during IBV propagation in cell culture results in significantly increased viral titres. Using a panel of IBV strains, exhibiting varied tropisms, the effects of spike cleavage on entry and replication were assessed by serial passage cell culture in the presence of trypsin. Replication could be maintained over serial passages, indicating that the addition of exogenous protease is sufficient to overcome the barrier to infection. Mutations were identified in both S1 and S2 subunits following serial passage in cell culture. This work provides a proof of concept that exogenous proteases can remove the barrier to IBV replication in otherwise non-permissive cells, providing a platform for further study of elusive field strains and enabling sustainable vaccine production in vitro.


Assuntos
Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Vírus da Bronquite Infecciosa/efeitos dos fármacos , Vírus da Bronquite Infecciosa/fisiologia , Tripsina/uso terapêutico , Tropismo Viral/efeitos dos fármacos , Animais , Linhagem Celular , Chlorocebus aethiops , Gammacoronavirus/efeitos dos fármacos , Vírus da Bronquite Infecciosa/metabolismo , Cinética , Inoculações Seriadas , Glicoproteína da Espícula de Coronavírus/metabolismo , Células Vero , Proteínas do Envelope Viral/metabolismo , Vírion/efeitos dos fármacos , Vírion/metabolismo , Replicação Viral/efeitos dos fármacos
8.
Infect Genet Evol ; 84: 104498, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32771700

RESUMO

New coronavirus SARS-CoV-2 is capable to infect humans and cause a novel disease COVID-19. Aiming to understand a host genetic component of COVID-19, we focused on variants in genes encoding proteases and genes involved in innate immunity that could be important for susceptibility and resistance to SARS-CoV-2 infection. Analysis of sequence data of coding regions of FURIN, PLG, PRSS1, TMPRSS11a, MBL2 and OAS1 genes in 143 unrelated individuals from Serbian population identified 22 variants with potential functional effect. In silico analyses (PolyPhen-2, SIFT, MutPred2 and Swiss-Pdb Viewer) predicted that 10 variants could impact the structure and/or function of proteins. These protein-altering variants (p.Gly146Ser in FURIN; p.Arg261His and p.Ala494Val in PLG; p.Asn54Lys in PRSS1; p.Arg52Cys, p.Gly54Asp and p.Gly57Glu in MBL2; p.Arg47Gln, p.Ile99Val and p.Arg130His in OAS1) may have predictive value for inter-individual differences in the response to the SARS-CoV-2 infection. Next, we performed comparative population analysis for the same variants using extracted data from the 1000 Genomes project. Population genetic variability was assessed using delta MAF and Fst statistics. Our study pointed to 7 variants in PLG, TMPRSS11a, MBL2 and OAS1 genes with noticeable divergence in allelic frequencies between populations worldwide. Three of them, all in MBL2 gene, were predicted to be damaging, making them the most promising population-specific markers related to SARS-CoV-2 infection. Comparing allelic frequencies between Serbian and other populations, we found that the highest level of genetic divergence related to selected loci was observed with African, followed by East Asian, Central and South American and South Asian populations. When compared with European populations, the highest divergence was observed with Italian population. In conclusion, we identified 4 variants in genes encoding proteases (FURIN, PLG and PRSS1) and 6 in genes involved in the innate immunity (MBL2 and OAS1) that might be relevant for the host response to SARS-CoV-2 infection.


Assuntos
Infecções por Coronavirus/genética , Resistência à Doença/genética , Predisposição Genética para Doença , Interações Hospedeiro-Patógeno/genética , Metagenômica , Peptidil Dipeptidase A/genética , Pneumonia Viral/genética , Glicoproteína da Espícula de Coronavírus/genética , Alelos , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Proteínas do Olho/genética , Proteínas do Olho/imunologia , Furina/genética , Furina/imunologia , Frequência do Gene , Variação Genética , Genoma Humano , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Lectina de Ligação a Manose/genética , Lectina de Ligação a Manose/imunologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Pandemias , Peptidil Dipeptidase A/imunologia , Plasminogênio/genética , Plasminogênio/imunologia , Pneumonia Viral/imunologia , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/imunologia , Tripsina/genética , Tripsina/imunologia
9.
J Biosci Bioeng ; 130(5): 514-519, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32782194

RESUMO

We have investigated the potential of bile acid (BA)-binding short-chain peptides for suppressing cholesterol absorption in the intestine. In our previous report, we have revealed the physicochemical characteristics of high binding peptides using principal component analysis. In this study, we investigated the characteristics of amino acid residues of BA-binding short-chain peptides. We found that short-chain peptides containing lysine (K) and arginine (R) had a higher BA-binding ability than peptides containing other amino acids. Since short-chain tryptic peptides contain K or R residues, we focused on 4-mer, 5-mer, and 6-mer peptides, which were expectedly released from the edible proteins by trypsin. Forty-four short-chain peptides from lactoproteins (Bos taurus) and glutelin (Oryza sativa subsp. Japonica) were synthesized, and their BA micelle disruption activity was evaluated. We could observe such activities in nearly all tested peptides. We found that CEVFR, NGLK, and NSVFR had particularly high disruption activities. We determined that the 50% cholesterol concentration decrease value (DC50) of the micellar solution upon peptide addition was almost the same in case of the aforementioned peptides as that of the VAWWMY as a positive control. In addition, 4-mer and 5-mer peptides had higher BA micelle disruption activity than 6-mer peptides. Our results confirmed that the BA binding and micelle disruption activities were significantly higher if the short-chain peptides contained K and R residues.


Assuntos
Ácidos e Sais Biliares/química , Proteínas na Dieta/metabolismo , Micelas , Fragmentos de Peptídeos/química , Tripsina/metabolismo , Animais , Bovinos , Hidrólise
10.
J Med Chem ; 63(17): 9500-9511, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32787139

RESUMO

Peptidase inhibitors (PIs) have been broadly studied due to their wide therapeutic potential for human diseases. A potent trypsin inhibitor from Tityus obscurus scorpion venom was characterized and named ToPI1, with 33 amino acid residues and three disulfide bonds. The X-ray structure of the ToPI1:trypsin complex, in association with the mass spectrometry data, indicate a sequential set of events: the complex formation with the inhibitor Lys32 in the trypsin S1 pocket, the inhibitor C-terminal residue Ser33 cleavage, and the cyclization of ToPI1 via a peptide bond between residues Ile1 and Lys32. Kinetic and thermodynamic characterization of the complex was obtained. ToPI1 shares no sequence similarity with other PIs characterized to date and is the first PI with CS-α/ß motif described from animal venoms. In its cyclic form, it shares structural similarities with plant cyclotides that also inhibit trypsin. These results bring new insights for studies with venom compounds, PIs, and drug design.


Assuntos
Ciclotídeos/química , Ciclotídeos/metabolismo , Venenos de Escorpião/química , Tripsina/metabolismo , Sequência de Aminoácidos , Animais , Células CHO , Cricetulus , Ciclização , Modelos Moleculares , Ligação Proteica , Conformação Proteica
11.
Ann Surg ; 272(5): 863-870, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32833754

RESUMO

OBJECTIVE: We investigated the activation of pancreatic proenzymes and signs of peripancreatic inflammation in patients with clinically relevant postoperative pancreatic fistulas (POPFs). SUMMARY BACKGROUND DATA: An increase of systemic amylase concentration was associated with POPFs. This suggested parallels in the pathomechanisms between the development of POPFs and pancreatitis. METHODS: Trypsinogen, procathepsin B, and IL-6 concentrations as well as cathepsin B, myeloperoxidase and trypsin activities were determined throughout the first 7 postoperative days in drain fluids of 128 consecutive patients after pancreas resection. Histology and immunohistochemistry were performed in pancreatic specimens after total pancreatectomy due to complications and after placing experimental pancreatic sutures in the pancreatic tail of C57/Bl6 mice. RESULTS: Trypsin activity, cathepsin B activity and myeloperoxidase activity on the first postoperative day were elevated and predictive for clinically relevant pancreatic fistulas. Drain fluid stabilized trypsin activity and prevented the activation of the cascade of digestive enzymes. Leukocytes were the source of cathepsin B in drain fluid. Findings differed between fistulas after distal pancreatectomy and pancreatoduodenectomy. Immunohistochemistry of the pancreatic remnant revealed an inflammatory infiltrate expressing cathepsin B, independent of the presence of pancreatic fistulas. The infiltrate could be reproduced experimentally by sutures placed in the pancreatic tail of C57/Bl6 mice. CONCLUSIONS: Trypsinogen activation, increased cathepsin B activity and inflammation around the pancreato-enteric anastomosis on post operative day 1 are associated with subsequent clinically relevant POPFs after pancreatoduodenectomy. The parenchymal damage seems to be induced by placing sutures in the pancreatic parenchyma during pancreatic surgery.


Assuntos
Pancreatectomia , Fístula Pancreática/enzimologia , Complicações Pós-Operatórias/enzimologia , Amilases/metabolismo , Animais , Catepsina B/metabolismo , Precursores Enzimáticos/metabolismo , Feminino , Humanos , Inflamação/enzimologia , Interleucina-6/metabolismo , Masculino , Camundongos , Peroxidase/metabolismo , Estudos Prospectivos , Tripsina/metabolismo , Tripsinogênio/metabolismo
12.
Nat Commun ; 11(1): 3974, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769995

RESUMO

Bacillus thuringiensis Vip3 (Vegetative Insecticidal Protein 3) toxins are widely used in biotech crops to control Lepidopteran pests. These proteins are produced as inactive protoxins that need to be activated by midgut proteases to trigger cell death. However, little is known about their three-dimensional organization and activation mechanism at the molecular level. Here, we have determined the structures of the protoxin and the protease-activated state of Vip3Aa at 2.9 Å using cryo-electron microscopy. The reconstructions show that the protoxin assembles into a pyramid-shaped tetramer with the C-terminal domains exposed to the solvent and the N-terminal region folded into a spring-loaded apex that, after protease activation, drastically remodels into an extended needle by a mechanism akin to that of influenza haemagglutinin. These results provide the molecular basis for Vip3 activation and function, and serves as a strong foundation for the development of more efficient insecticidal proteins.


Assuntos
Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Motivos de Aminoácidos , Proteínas de Bactérias/ultraestrutura , Modelos Moleculares , Domínios Proteicos , Estrutura Secundária de Proteína , Tripsina/metabolismo
13.
Sci Rep ; 10(1): 11680, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32669617

RESUMO

Bioactive plant peptides have received considerable interest as potential antihypertensive agents with potentially fewer side effects than antihypertensive drugs. Here, the blood pressure-lowering effects of the Bowman-Birk protease inhibitor, BTCI, and its derived peptides, PepChy and PepTry, were investigated using normotensive (Wistar-WR) and spontaneously hypertensive rats (SHR). BTCI inhibited the proteases trypsin and chymotrypsin, respectively, at 6 µM and 40 µM, a 10-fold greater inhibition than observed with PepTry (60 µM) and PepChy (400 µM). These molecules also inhibited angiotensin converting enzyme (ACE) with IC50 values of 54.6 ± 2.9; 24.7 ± 1.1; and 24.4 ± 1.1 µM, respectively, occluding its catalytic site, as indicated by molecular docking simulation, mainly for PepChy and PepTry. Gavage administration of BTCI and the peptides promoted a decrease of systolic and diastolic blood pressure and an increase of renal and aortic vascular conductance. These effects were more expressive in SHR than in WR. Additionally, BTCI, PepChy and PepTry promoted coronary vasodilation and negative inotropic effects in isolated perfused hearts. The nitric oxide synthase inhibitor blunted the BTCI and PepChy, with no cardiac effects on PepTry. The findings of this study indicate a therapeutic potential of BTCI and its related peptides in the treatment of hypertension.


Assuntos
Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Contração Miocárdica/efeitos dos fármacos , Peptídeos/farmacologia , Inibidor da Tripsina de Soja de Bowman-Birk/farmacologia , Animais , Anti-Hipertensivos/química , Sítios de Ligação , Quimotripsina/química , Quimotripsina/metabolismo , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiopatologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Hipertensão/enzimologia , Hipertensão/fisiopatologia , Masculino , Simulação de Acoplamento Molecular , NG-Nitroarginina Metil Éster/química , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/química , Óxido Nítrico Sintase Tipo III/metabolismo , Peptídeos/síntese química , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Tripsina/química , Tripsina/metabolismo , Inibidor da Tripsina de Soja de Bowman-Birk/química , Vasodilatação/efeitos dos fármacos
14.
Sci Rep ; 10(1): 11731, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678161

RESUMO

The digestive enzyme chymotrypsin protects the pancreas against pancreatitis by reducing harmful trypsin activity. Genetic deficiency in chymotrypsin increases pancreatitis risk in humans and pancreatitis severity in mice. Pancreatic chymotrypsin is produced in multiple isoforms including chymotrypsin B1, B2, C and chymotrypsin-like protease (CTRL). Here we investigated the role of CTRL in cerulein-induced pancreatitis in mice. Biochemical experiments with recombinant mouse enzymes demonstrated that CTRL cleaved trypsinogens and suppressed trypsin activation. We generated a novel CTRL-deficient strain (Ctrl-KO) using CRISPR-Cas9 genome engineering. Homozygous Ctrl-KO mice expressed no detectable CTRL protein in the pancreas. Remarkably, the total chymotrypsinogen content in Ctrl-KO mice was barely reduced indicating that CTRL is a low-abundance isoform. When given cerulein, Ctrl-KO mice exhibited lower intrapancreatic chymotrypsin activation and a trend for higher trypsin activation, compared with C57BL/6N mice. Despite the altered protease activation, severity of cerulein-induced acute pancreatitis was similar in Ctrl-KO and C57BL/6N mice. We conclude that CTRL is a minor chymotrypsin isoform that plays no significant role in cerulein-induced pancreatitis in mice.


Assuntos
Pâncreas/enzimologia , Pancreatite/etiologia , Pancreatite/metabolismo , Serina Endopeptidases/deficiência , Doença Aguda , Animais , Biópsia , Linhagem Celular , Quimotripsina/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , Expressão Gênica , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Pancreatite/patologia , Peroxidase/genética , Peroxidase/metabolismo , Índice de Gravidade de Doença , Tripsina/metabolismo
15.
Sci Rep ; 10(1): 11855, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678286

RESUMO

Catheterization is a common medical operation to diagnose and treat cardiovascular diseases. The blood vessel lumen is coated with endothelial glycocalyx layer (EGL), which is important for the permeability and diffusion through the blood vessels wall, blood hemodynamics and mechanotransduction. However EGL's role in catheter-blood vessel friction is not explored. We use a porcine aorta to mimic the blood vessel and a catheter loop was made to rub in reciprocating sliding mode against it to understand the role of catheter loop curvature, stiffness, normal load, sliding speed and EGL on the friction properties. Trypsin treatment was used to cause a degradation of the EGL. Decrease in catheter loop stiffness and EGL degradation were the strongest factors which dramatically increased the coefficient of friction (COF) and frictional energy dissipation at the aorta-catheter interface. Increasing sliding speed caused an increase but increase in normal load first caused a decrease and then an increase in the COF and frictional energy. These results provide the basic data for safety of operation and damage control during catheterization in patients with degraded EGL.


Assuntos
Aorta/química , Endotélio Vascular/química , Glicocálix/química , Mecanotransdução Celular/fisiologia , Animais , Aorta/efeitos dos fármacos , Fenômenos Biomecânicos , Cateterismo/efeitos adversos , Endotélio Vascular/efeitos dos fármacos , Fricção , Glicocálix/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Permeabilidade , Suínos , Técnicas de Cultura de Tecidos , Tripsina/farmacologia , Dispositivos de Acesso Vascular/efeitos adversos
16.
Chem Biol Interact ; 328: 109201, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32717190

RESUMO

The caseinate and glycated caseinate generated from the transglutaminase-catalyzed reaction of caseinate and oligochitosan were digested using pepsin and trypsin, and the activity of the resultant digests was measured in rat intestinal epithelial cell line (IEC-6) using several biological responses as indicators. Compared with the caseinate digest, the glycated caseinate digest had similar contents in 17 amino acids but less reactable -NH2 contents, and 6.57 g glucosamine per kg protein; moreover, it showed higher activity in the cells (P < 0.05) to promote cell growth, accumulate the cell-cycle progression at the S-phase, and prevent the camptothecin-induced cell apoptosis. The glycated caseinate digest also showed higher differentiation activity in the cells than the caseinate digest, resulting in enhanced activities of the three brush-border membrane enzymes (P < 0.05) and increased microvilli on the cell surfaces. The real-time reverse transcription-polymerase chain reaction, Western-blot assay, and Dickkopf-1 (a receptor inhibitor of the Wnt/ß-catenin signaling pathway) were used to determine both gene and protein expression changes in the cells. A Wnt/ß-catenin signaling pathway responsible for these enhanced effects was proposed because the five genes (glycogen synthase kinase 3ß, Wnt3a, ß-catenin, c-Myc, and cyclin D1) and three proteins (nuclear and cytosolic ß-catenin, cyclin D1, and c-Myc) as part of this signaling pathway were regulated in the treated cells. The oligochitosan glycation of caseinate induced by transglutaminase is thus suggested endowing the peptic-tryptic caseinate digest with higher activity in the cells through its effects on the Wnt/ß-catenin signaling pathway.


Assuntos
Caseínas/metabolismo , Quitina/análogos & derivados , Enterócitos/metabolismo , Pepsina A/metabolismo , Tripsina/metabolismo , Via de Sinalização Wnt , Animais , Apoptose , Bovinos , Pontos de Checagem do Ciclo Celular , Diferenciação Celular/genética , Proliferação de Células , Sobrevivência Celular , Quitina/metabolismo , Enterócitos/citologia , Enterócitos/ultraestrutura , Regulação da Expressão Gênica/efeitos dos fármacos , Glicosilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética
17.
PLoS One ; 15(7): e0236740, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32722706

RESUMO

Tryptic digestion of proteins followed by liquid chromatography with tandem mass spectrometry analysis is an extensively used approach in proteomics research and biopharmaceutical product characterization, owing to the high level of cleavage fidelity produced with this technique. However, nonspecific trypsin cleavages have been frequently reported and shown to be related to a number of digestion conditions and predigestion sample treatments. In this work, we reveal that, for a number of commercial trypsins, reconstitution and storage conditions can have a significant impact on the occurrence of trypsin nonspecific cleavages. We analyzed the tryptic digestion of a variety of biotherapeutics, using trypsins reconstituted under different conditions. The results indicate that, for many commercial trypsins, commonly recommended reconstitution/storage conditions (mildly acidic, e.g., 50 mM acetic acid, 1 mM HCl) can actually promote nonspecific trypsin activities, which are time dependent and can be as high as 20% in total relative abundance. In contrast, using water for reconstitution and storage can effectively limit nonspecific cleavages to 1%. Interestingly, the performances of different commercial trypsins were found to be quite distinct in their levels of nonspecific cleavages and responses to the two reconstitution conditions. Our findings demonstrate the importance of choosing the appropriate trypsin for tryptic digestion and the necessity of assessing the impact of trypsin reconstitution and storage on nonspecific cleavages. We advocate for manufacturers of commercial trypsins to reevaluate manufacturing processes and reconstitution/storage conditions to provide good cleavage specificity.


Assuntos
Ácidos/química , Fragmentos de Peptídeos/metabolismo , Proteínas/metabolismo , Proteólise , Proteômica/métodos , Tripsina/metabolismo , Humanos , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/isolamento & purificação
18.
Arch Biochem Biophys ; 690: 108460, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32603715

RESUMO

BACKGROUND: Our previous research revealed that trypsin is abundantly expressed in atherosclerotic plaques and its distribution overlaps with that of matrix metalloproteinase-9 (MMP-9). This study was performed to explore the possible roles of trypsin in vulnerable atherosclerotic plaque formation. METHODS AND RESULTS: Twenty-four rabbits were randomly assigned to a normal (control) group, an atherosclerosis (experimental) group and a trypsin inhibitor (aprotinin) group. In the 13th feeding week, the aprotinin group was treated with 5 mg/kg/day aprotinin via ear vein for 4 weeks. At the end of the 16th week, coronary arterial and aortic expression of trypsin, proteinase-activated receptor-2 (PAR-2), activated MMP-9, and pro-inflammatory cytokines were significantly greater in the experimental group than in the control group. Aprotinin decreased trypsin expression and activation in plaques, blocked PAR-2 and MMP-9 activation, and decreased cytokine expression; it also increased fibrous cap thickness, decreased the intima-media thickness and intimal/medial ratio, thus significantly ameliorating plaque vulnerability. Upregulated trypsin, MMP-9 and PAR-2 were also found in coronary intimal atherosclerotic plaques of patients undergoing coronary artery bypass grafting. CONCLUSIONS: Ectopic trypsin was significantly upregulated in atherosclerotic plaques, which increased pro-inflammatory cytokine levels by activating PAR-2 and promoted plaque instability by activating proMMP-9, thereby promoting atherosclerosis and plaque vulnerability. In addition, the high trypsin expression in human coronary intimal atherosclerotic plaques suggests that targeting trypsin may be a new strategy for acute coronary syndrome prevention.


Assuntos
Aterosclerose/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Placa Aterosclerótica/química , Tripsina/metabolismo , Animais , Aorta/química , Aprotinina/administração & dosagem , Aprotinina/metabolismo , Espessura Intima-Media Carotídea , Citocinas/metabolismo , Regulação da Expressão Gênica , Humanos , Masculino , Coelhos , Receptor PAR-2/metabolismo , Tripsina/genética , Inibidores da Tripsina/administração & dosagem , Inibidores da Tripsina/metabolismo
19.
J Biol Chem ; 295(36): 12686-12696, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32675285

RESUMO

Type II transmembrane serine proteases (TTSPs) are a group of enzymes participating in diverse biological processes. Some members of the TTSP family are implicated in viral infection. TMPRSS11A is a TTSP expressed on the surface of airway epithelial cells, which has been shown to cleave and activate spike proteins of the severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome coronaviruses (CoVs). In this study, we examined the mechanism underlying the activation cleavage of TMPRSS11A that converts the one-chain zymogen to a two-chain enzyme. By expression in human embryonic kidney 293, esophageal EC9706, and lung epithelial A549 and 16HBE cells, Western blotting, and site-directed mutagenesis, we found that the activation cleavage of human TMPRSS11A was mediated by autocatalysis. Moreover, we found that TMPRSS11A activation cleavage occurred before the protein reached the cell surface, as indicated by studies with trypsin digestion to remove cell surface proteins, treatment with cell organelle-disturbing agents to block intracellular protein trafficking, and analysis of a soluble form of TMPRSS11A without the transmembrane domain. We also showed that TMPRSS11A was able to cleave the SARS-CoV-2 spike protein. These results reveal an intracellular autocleavage mechanism in TMPRSS11A zymogen activation, which differs from the extracellular zymogen activation reported in other TTSPs. These findings provide new insights into the diverse mechanisms in regulating TTSP activation.


Assuntos
Células Epiteliais/metabolismo , Proteínas de Membrana/metabolismo , Proteólise , Serina Proteases/metabolismo , Células A549 , Células Cultivadas , Células HEK293 , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/genética , Mutação , Domínios Proteicos , Transporte Proteico , Mucosa Respiratória/citologia , Serina Proteases/química , Serina Proteases/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Tripsina/metabolismo
20.
Res Vet Sci ; 132: 54-56, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32485464

RESUMO

The European eel has recently been included on the Red List of the International Union for Conservation of Nature (IUCN) as a critically endangered species. The rearing of Anguilla larvae is seen as a key bottleneck to the mass production of glass eels since very little ecological information is available regarding their natural nutrition. Studies of digestive physiology and ontogenetic development in eel larvae could provide useful information for solving some of the puzzles regarding larval fish culture. The aim of this study was to characterize the ontogeny of pancreatic enzymes (trypsin, lipase and amylase) and a peptide hormone regulator of pancreatic secretion (cholecystokinin) in terms of gene expression in European eel larvae from day 0 (P0) of hatching to 5, 10, 15 and 20 days post hatching during fasting. The results in the present study showed that all the genes selected were present, with different levels of expression and increasing trends, during larval development. At P0, the increase in the gene expression of lipase and amylase was higher than that of trypsin and cholecystokinin, confirming that enzymatic activity began before mouth opening and that larvae, provided with a complete enzymatic set, might have the capacity of digesting and absorbing various nutrients.


Assuntos
Anguilla/metabolismo , Fenômenos Fisiológicos do Sistema Digestório , Proteínas de Peixes/metabolismo , Privação de Alimentos/fisiologia , Amilases/metabolismo , Anguilla/crescimento & desenvolvimento , Fenômenos Fisiológicos da Nutrição Animal , Animais , Aquicultura , Colecistocinina/metabolismo , Feminino , Lipase/metabolismo , Tripsina/metabolismo
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