BACKGROUND Endogenous regeneration of pancreatic isletβ-cells is a path to cure both type 1 and advanced type 2 diabetes.Pancreatic cancer cell line-1(PANC-1),a human pancreatic islet progenitor cell line,can be indu...BACKGROUND Endogenous regeneration of pancreatic isletβ-cells is a path to cure both type 1 and advanced type 2 diabetes.Pancreatic cancer cell line-1(PANC-1),a human pancreatic islet progenitor cell line,can be induced by trypsin to differentiate into insulin-secreting islet-like aggregates(ILAs).However,the underlying mechanism has not been explored.AIM To explore the mechanism and signaling pathway of trypsin-induced differentiation of islet progenitor cells into insulin-secreting cells.METHODS PANC-1 cells were induced by trypsin to form ILAs and differentiate into insulinsecreting cells.Clustered regularly interspaced short palindromic repeats(CRISPR)-associated protein 9 knockout and small interfering RNA knockdown techniques were used to investigate membrane proteins and downstream signaling pathways involved in the process.RESULTS The extracellular domain of membrane receptor E-cadherin hydrolyzed by trypsin induced the aggregation of PANC-1 cells and stimulated E-cadherin-recruited casein kinase-1γ3,which specifically phosphorylated the Ser655/Thr658 site ofα-catenin in the cadherin-catenin complex,participating in the process of PANC-1 differentiation and affecting the maturation of differentiated ILAs.CONCLUSION The current study reveals the mechanism by which trypsin promotes PANC-1 cell differentiation into islet-like cells,providing a novel approach for endogenous isletβ-cell regeneration.展开更多
During postmortem storage,fluoride in Antarctic krill can be enriched in the muscle.Trypsin,as the most important digestive enzyme in Antarctic krill with a high activity in low temperature,plays a potential role in t...During postmortem storage,fluoride in Antarctic krill can be enriched in the muscle.Trypsin,as the most important digestive enzyme in Antarctic krill with a high activity in low temperature,plays a potential role in this process.In this study,endogenous trypsin was purified and its properties were investigated.The involvement of trypsin in the generation of free fluoride from Antarctic krill cuticle was explored.Cuticle microstructure before and after hydrolysis was compared with scanning electron microscopy,and the ash samples of the hydrolyzed Antarctic krill cuticle were analyzed with X-ray diffraction,Fourier transform infrared spectroscopy,and electron dispersive spectroscopy,respectively.Mass spectrometry analysis and inhibition tests confirmed that the purified enzyme was endogenous trypsin.Results of the present study indicated that trypsin digestion caused the increases of the concentrations of both fluoride ions and free amino N simultaneously,while the protein coated on the cuticle surface was dissolved too.However,no compositional change was detected in the cuticle inorganic salts.These findings suggest that trypsin triggered free fluoride release from Antarctic krill cuticle.In addition,the kinetics of free fluoride release could be described by the equation C_(W)=(1-0.97^(-0.006t)-0.03e^(0.0558t))×337.53+10.50.The present study improved the understanding of the role of trypsin in free fluoride release from Antarctic krill cuticle,facilitating future studies aimed at reducing the fluoride content in krill protein during Antarctic krill processing.展开更多
Phlorizin(PHL)is a natural compound with strong antioxidant properties mainly found in apples.In this paper,the interaction mechanism of PHL with pepsin and trypsin was comparatively evaluated by computer simulation,f...Phlorizin(PHL)is a natural compound with strong antioxidant properties mainly found in apples.In this paper,the interaction mechanism of PHL with pepsin and trypsin was comparatively evaluated by computer simulation,fluorescence spectra,circular dichroism(CD),and Fourier transform infrared(FT-IR)spectra at a molecular level.Fluorescence spectra showed that PHL quenches the pepsin/trypsin by static quenching.Thermodynamic parameters indicated that PHL binds to pepsin mainly through hydrogen bonds and van der Waals forces,and that of trypsin was electrostatic forces.The ground state complexes PHL and protease have a moderate affinity of 105 L/mol PHL binds more strongly to trypsin than to pepsin.CD and FT-IR spectra results showed that pepsin/trypsin decreased theβ-sheet content and slightly changed its secondary structure upon PHL.These experimental results are mutually verified with the predicted computer-aid simulation results.Upon PHL and trypsin binding,the antioxidant capacity of PHL was elevated.Nevertheless,the antioxidant capacity of PHL was decreased after binding to pepsin.This work elucidates the binding of PHL binding mechanisms to pepsin/trypsin and provides useful information for the digestion of PHL to improve the application of PHL in food processing.展开更多
AIM:To compare the safety and clinical outcomes of subconjunctival trypsin and dexamethasone(DEX)injections in the treatment of anterior chamber fibrin exudates in eyes with globe rupture following primary wound repai...AIM:To compare the safety and clinical outcomes of subconjunctival trypsin and dexamethasone(DEX)injections in the treatment of anterior chamber fibrin exudates in eyes with globe rupture following primary wound repair and vitrectomy.METHODS:A retrospective analysis included 42 males and 10 females(mean age 46.0±6.0y,range 34 to 58y)who underwent primary wound sutures and vitrectomy for globe rupture.Patients with pupil-covered fibrinous exudate or/and membrane in the anterior chamber were treated.On the first postoperative day,subconjunctival injections of either 5000 units(0.4 mL)of trypsin solution(n=25)or 0.5 mL(1 mg)DEX(n=27)were administered to accelerate exudate absorption.Efficacy was assessed by observing break time and partial absorption of the fibrin exudate membrane.Safety and comfort were evaluated by monitoring intraocular pressure(IOP),allergy,pain,and foreign body sensation.RESULTS:Both groups achieved 1/3 absorption of the anterior chamber fibrin exudate membrane,but the trypsin group exhibited shorter break time and partial absorption time compared to the DEX group(P<0.05).Trypsin treatment was also less irritating to patients.No adverse reactions were reported,and IOP remained stable.Visual acuity improved in both groups without statistical difference.CONCLUSION:Compared to DEX,trypsin demonstrates a shorter absorption time for the fibrin exudate membrane with a more comfortable process in treating pupil-covered fibrinous exudate or/and membrane after vitrectomy for globe rupture.展开更多
Herein,a novel method for fl uorometric detection of soybean trypsin inhibitor(SBTI)activity based on a water-soluble poly(diphenylacetylene)derivative was reported.Fluorescence quenching of the polymer via p-nitroani...Herein,a novel method for fl uorometric detection of soybean trypsin inhibitor(SBTI)activity based on a water-soluble poly(diphenylacetylene)derivative was reported.Fluorescence quenching of the polymer via p-nitroaniline,produced from the trypsin-catalyzed decomposition of N-benzoyl-DL-arginine-4-nitroanilide hydrochloride(L-BAPA),was well described using the Stern-Volmer equation.SBTI activity was quantitatively assessed based on changes in the fl uorescence intensity of the polymer.This strategy has several advantages,such as high sensitivity and ease of operation.Moreover,its applicability to other biochemical analyses is promising.展开更多
During post-harvest storage of Cucumis sativus fruit,the application of trypsin treatment could increaseflavonoid compound levels and reduce oxidative damage.To investigate the mechanism of trypsin-inducedflavonoid bio-...During post-harvest storage of Cucumis sativus fruit,the application of trypsin treatment could increaseflavonoid compound levels and reduce oxidative damage.To investigate the mechanism of trypsin-inducedflavonoid bio-synthesis in C.sativus,we conducted a combined analysis of transcriptomics and widely targeted metabolomics.One hundred and seventy-five significantly different metabolites were obtained from metabolomics data.The kyoto encyclopedia of genes and genomes(KEGG)functional enrichment results indicated that these metabolites were mainly involved in the phenylpropanoid biosynthesis pathway.By combining the results of the weighted gene co-expression network analysis(WGCNA)with the 130 upregulated phenylpropanoid metabolites,22 significantly upregulated phenylpropanoid metabolites were identified.Trilobatin was identified as the most prominent meta-bolite through cluster analysis and variable importance in projection(VIP)analysis.High performance liquid chro-matography(HPLC)experiments confirmed that trilobatin was the key metabolite induced by trypsin.The transcriptomic results showed that 1068 genes in the brown module of WGCNA were highly positively correlated withflavonoid biosynthesis.The gene set enrichment analysis(GSEA)identified leading edges in 4 key KEGG path-ways.Finally,combined with WGCNA and GSEA analysis results,35 core genes were obtained.The co-expression network of transcriptomics and metabolomics suggested that CsWRKY28 and CsMYC2 regulated the biosynthesis of trilobatin.The quantitative real-time polymerase chain reaction(RT-qPCR)and dual luciferase experiments con-firmed the activation effect of CsWRKY28 on CsMYC2 and downstream target genes.This study revealed the key transcription factors involved in the trypsin-controlled biosynthesis of trilobatin in C.sativus and provided a new theoretical basis for elucidating the molecular mechanism of trypsin preservation.展开更多
Trypsin,a novel superoxide scavenger,significantly enhances the storage quality of Hylocereus undatus(H.undatus).To elucidate the preservation mechanism of trypsin on H.undatus,a widely targeted metabolomic analysis,a...Trypsin,a novel superoxide scavenger,significantly enhances the storage quality of Hylocereus undatus(H.undatus).To elucidate the preservation mechanism of trypsin on H.undatus,a widely targeted metabolomic analysis,and transcriptomics analysis were conducted.Firstly,a total of 453 metabolites were identified,with organic acids and their derivatives constituting the largest proportion(25%).Amino acids and their metabolites,prominent among organic acids,were further analyzed.Among them,73 metabolites were associated with amino acids,and 37 exhibited significant differences.The most enriched Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway was arginine biosynthesis(map00220),with polyamine metabolites showing the most pronounced differences,particularly spermine(FC=1.7594).Compared with the control group,4-hydroxy-2-oxoglutaric acid was significantly upregulated(FC=2.117)in the process of spermine biosynthesis.Furthermore,the results of Gene Ontology(GO)and KEGG enrichment analysis of the H.undatus transcriptome profile revealed that trypsin treatment led to 187 differentially expressed genes associated with arginine.Both GO and KEGG analyses exhibited significant enrichment in the spermine biosynthetic process(GO:0006597)(map:00220)within the arginine biosynthesis pathway.Moreover,most enzymes and metabolites within the spermine biosynthesis pathway in H.undatus were upregulated.The results of the PPI network highlighted that ADC,SPDS,and SAMDC,among others,were pivotal proteins involved in trypsin-regulated arginine metabolism and spermine synthesis.This study revealed that trypsin could significantly delay postharvest senescence of H.undatus at room temperature.This effect might be attributed to trypsin triggering the synthesis of 4-hydroxy-2-oxoglutaric acid in the fruit peel,thereby promoting the biosynthesis of spermine and other polyamines.展开更多
A reliable and validated HPLC method was established for the assay of trypsin inhibitors（TI）and it was used in the investigation of the active TI components inMomordica cochinchinensis（Cucurbitaceae family）.The un...A reliable and validated HPLC method was established for the assay of trypsin inhibitors（TI）and it was used in the investigation of the active TI components inMomordica cochinchinensis（Cucurbitaceae family）.The underlying principle of the assay is the measurement of the decrease in trypsin activity due to the presence of TI in analyzed samples,which was achieved by using HPLC separation and quantification of p-nitroanilide that was generated by tryptic hydrolysis of N-α-benzoyl-DL-arginine -4-nitroanilide.The results showed that the HPLC method had higher selectivity than conventional spectrophotometric assay.展开更多
By 30% - 60% (NH4)(2)SO4 fractional precipitation, anion-exchange chromatography on DEAE-Sepharose CL-6B, gel filtration on Sephacryl S-200 and anion-exchange chromatography on Waters AP-1 column (Protein(PM)-Pak DEAE...By 30% - 60% (NH4)(2)SO4 fractional precipitation, anion-exchange chromatography on DEAE-Sepharose CL-6B, gel filtration on Sephacryl S-200 and anion-exchange chromatography on Waters AP-1 column (Protein(PM)-Pak DEAE 15HR), a proteinase which can inactivate soybean trypsin inhibitor (STI) was purified from mung bean ( Vigna rabiata (L.) Wilezek) sprouts. Its molecular weight was estimated to be 29.8 kD by SDS-PAGE, and its K-m and V-max for STI were 769.2 N-alpha -benzoyl-L-arginine ethyl ester BAEE/mL and 115.3 BAEE . mL(-1) . min(-1) respectively. This proteinase was stable at temperatures lower than 50 degreesC and pH 6.5 - 8.5, and 90.91% STI activity of defatted soybean powder was inactivated by this preparation, with proteolytic activity 5 000 BAEE/mL at 50 degreesC and pH 8.0 in 4 h.展开更多
Abstract The digestive enzyme activity and mRNA level of trypsin during the embryonic development of Cherax quadricarinatus were analyzed using biochemical and Fluorogenic Quantitative PCR （FQ-PCR） methods. The resu...Abstract The digestive enzyme activity and mRNA level of trypsin during the embryonic development of Cherax quadricarinatus were analyzed using biochemical and Fluorogenic Quantitative PCR （FQ-PCR） methods. The results show that the activities of trypsin and chymotrypsin had two different change patterns. Trypsin specific activity increased rapidly in the early stages of development and still remained high in preparation for the hatch stage. However, chymotrypsin activity peaked in stage 4 of embryonic development and decreased significantly in the last stage. The mRNA level of trypsin was elevated in all stages and two peak values were observed in stages 2 and 5 respectively. The results indicate that trypsin is very important for the utilization of the yolk during embryonic development and for the assimilation of dietary protein for larvae. The gene of trypsin is probably regulated at transcriptional level. The mRNA levels of trypsin can reflect not only trypsin activity, but also the regulatory mechanism for expression of trypsin gene to a certain degree.展开更多
Macroporous cross-linking chitosan layer coated on silica gel （CTS-SiO2） was prepared by phase inversion and polyethylene glycol （PEG）molecular imprinting methods. Formation of macroporous surtace was investigated...Macroporous cross-linking chitosan layer coated on silica gel （CTS-SiO2） was prepared by phase inversion and polyethylene glycol （PEG）molecular imprinting methods. Formation of macroporous surtace was investigated by scanning electron microscopy （SEM） and BET analysis.The prepared bead was activated by reacting with 1,2-ethylene digiycidyl ether for introducing epoxy groups, and trypsin could be efficiently immobilized on the bead as a biospecific ligand.The bead bearing trypsin was employed to purify trypsin inhibitor （TIs） from egg white as affinity adsorbent.展开更多
SDS-PAGE was applied to determine trypsin activity and inhibition. After the hydrolysis by trypsin to substrate bovine serum albulnin (BSA) under different temperatures and pH, the hydrolysis degree of BSA was conduct...SDS-PAGE was applied to determine trypsin activity and inhibition. After the hydrolysis by trypsin to substrate bovine serum albulnin (BSA) under different temperatures and pH, the hydrolysis degree of BSA was conducted using SDS-PAGE. From the quantitative analysis to the electrophoresis bands of BSA and its hydrolysis products in SDS-PAGE pattern, the change of trypsin activity was determined, and then the optimum temperature at 40°C and the optimum pH at pH 8.5 - 8.7 for trypsin activity were obtained. All the target bonds in BSA molecule could be hydrolyzed at the same time by trypsin. The inhibition was due to the binding of inhibitor to trypsin, which made it impossible for trypsin to touch the substrate protein. SDS-PAGE was demonstrated to be also an effect method for assaying the characteristics of trypsin activity and its inhibition.展开更多
The aim of the present study was to optimize trypsin inhibitor degradation in soybean meal by solid-state fermentation （SSF） with Lactobacillus brevis and Aspergillus oryzae, and to determine the effect of SSF on ph...The aim of the present study was to optimize trypsin inhibitor degradation in soybean meal by solid-state fermentation （SSF） with Lactobacillus brevis and Aspergillus oryzae, and to determine the effect of SSF on phytic acid, crude protein, crude fat, and amino acid profile. Response surface methodology （RSM） with Box-Behnken design was used to optimize SSF. The optimal conditions derived from RSM for L. brevis fermentation were： pH=5. 1; inoculum size=10%; duration=72 h; substrate to water ratio=1.5. The minimum content of trypsin inhibitors was 6.4 mg g^-1 dry matter. The optimal conditions derived from RSM for A. oryzae fermentation were： substrate to water ratio= 0.8 1; inoculum size=4%; duration=120 h. The minimum content of trypsin inhibitors was 1.6 mg g^-1 dry matter. Both L. brevis and A. oryzae decreased trypsin inhibitors dramatically （57.1 and 89.2% respectively）. L. brevis fermentation did not affect phytic acid （0.4%） and crude fat （5.2%） considerably, whereas A. oryzae fermentation degraded phytic acid （34.8%） and crude fat （22.0%） contents to a certain extent. Crude protein content was increased after both fermentation （6.4 and 12.9% for L. brevis and A. oryzae respectively）. Urease activity was reduced greatly （83.3 and 58.3% for L. brevis and A. oryzae respectively）. In conclusion, SSF with A. oryzae and L. brevis reduced trypsin inhibitor content and modified major macronutrients in soybean meal.展开更多
BACKGROUND: Urinary trypsin inhibitor (UTI) inhibits the inflammatory response and protects against ischemia-reperfusion (I/R) injury. The inflammatory response is mediated by nuclear factor-kappa B (NF-kappa B) and i...BACKGROUND: Urinary trypsin inhibitor (UTI) inhibits the inflammatory response and protects against ischemia-reperfusion (I/R) injury. The inflammatory response is mediated by nuclear factor-kappa B (NF-kappa B) and its related target genes and products such as vascular endothelial cell adhesion molecule and CXC chemokines. We aimed to assess the roles of those mediators in a UTI-treated mouse model of hepatic I/R injury. METHODS: Treatment group 1 (UTI given 5 minutes prior to liver ischemia), treatment group 2 (UTI given 5 minutes after the anhepatic phase) and a control group were investigated. Blood and liver samples were obtained and compared at 1, 3, 6 and 24 hours after reperfusion. RESULTS: Attenuation of pathological hepatocellular damage was greater in the treatment groups than in the control group (P < 0.05). Compared with the control group, the UTI treatment groups showed significantly lower serum alanine aminotransferase and aspartate aminotransferase levels, decreased myeloperoxidase activity, and reduced NF-kappa B activation. Also downregulated was the expression of tumor necrosis factor-alpha, cytokine-induced neutrophil chemoattractant, and macrophage inflammatory protein-2 at the mRNA level. P-selectin protein and intercellular adhesion molecule-1 protein expression were also downregulated. In addition, the treatment group I showed a better protective effect against I/R injury than the treatment group 2. CONCLUSIONS: UTI reduces NF-kappa B activation and downregulates the expression of its related mediators, followed by the inhibition of neutrophil aggregation and infiltration in hepatic I/R injury. The protective role of UTI is more effective in prevention than in treatment.展开更多
AIM: To assess the effect of non-selective ETA/B (LU 302872)and selective ETA (LU 302146) antagonist on pancreatic histology and ultrastructure of acinar cells in connection with trypsinogen activation in early caerul...AIM: To assess the effect of non-selective ETA/B (LU 302872)and selective ETA (LU 302146) antagonist on pancreatic histology and ultrastructure of acinar cells in connection with trypsinogen activation in early caerulein-induced AP.METHODS: Male Wistar rats with caerulein-induced AP,lasting 4 h, were treated i.p. with 10 and 20 mg/kg b.w.of each antagonist. Edema, inflammatory infiltration,necrosis and vacuolization of acinar cells in the pancreas were scored at 0-3 scale. Free active trypsin (FAT), total potential trypsin (TPT) after activation with enterokinase,and index of trypsinogen activation (%FAT/TPT) were assayed in pancreatic homogenates.RESULTS: In untreated AP, the edema, inflammatory infiltration, necrosis and vacuolization increased as compared to control healthy rats (P＜0.01). None of the treatment exerted any meaningful effect on the edema and inflammatory infiltration. The selective antagonist increased slightly the necrosis score to 0.82±0.06 at higher dose (P＜0.05) vs 0.58±0.06 in untreated AP. The nonselective antagonist increased slightly the vacuolization score to 2.41±0.07 at higher dose (P＜0.01) vs 1.88±0.08in untreated AP. The decrease in the number of zymogen granules, disorganization of endoplasmic reticulum,autophagosomes and cytoplasmic vacuoles were more prominent in treated AP than in untreated AP groups.%FAT/TPT in untreated AP increased about four times (18.4±3.8 vs4.8±1.3 in control group without AP, P＜0.001).Treatment of AP with both antagonists did not affect significantly augmented trypsinogen activation.CONCLUSION: The treatment with endothelin-1 receptors (non-selective ETA/B and selective ETA) antagonists has essential effect neither on the edema and inflammatory infiltration nor on trypsinogen activation observed in the early course of caerulein-induced AP. Nevertheless a slight increase of the necrosis and vacuolization score and some of the ultrastructural data could suggest the possibility of their undesired effects in caerulein-induced AP at investigated doses.展开更多
In this article, the influence factors of trypsin extracted from crude pancreatin was investigated, and scanning turmeling microscope（STM） was used to observe the image of trypsin in butane-diacid-2-ethyl-hexyl-este...In this article, the influence factors of trypsin extracted from crude pancreatin was investigated, and scanning turmeling microscope（STM） was used to observe the image of trypsin in butane-diacid-2-ethyl-hexyl-ester-sulfonic sodium （AOT）/iso-octane reversed micelles. The STM image showed that trypsins bounded in reversed micelles was rigid, which weakened its conjugative effect and caused maximum ultraviolet absorption and fluorescence emissive absorption moving toward blue waves. AOT concentration, pH and cations were the main influence factors of extraction. Specifically, extraction percentage of trypsin decreased with the increase of AOT concentration from 0.01 to 0.1mol·L^-1. When pH value is from 5.30 to 10.0, i.e. less than pI of trypsin, the extraction percentage is raised with the different increase of pI-pH, but when the pH value is less than 5.20, the extraction percentage is decreased with the acidity added. Besides, the extraction efficiency is negative, related with the concentrations of Ca^2＋, Na^＋, K^＋ which were in the range of 0.2-1.0mol.L^-1, and influence of concentration of Ca^2＋ is greater than that of Na^＋, and K^＋ which has the minimum impact with the same concentration. Finally, optimum conditions to extract trypsin were： AOT reversed micelles 0.05mol·L^-1, trypsin concentration in crude pancreatin solution 3mg·ml^-1, pH 5.2-- 5.3, ratio （by volume） of extraction phase to strip-extraction phase 1 ： 1, and time of 5min. The corresponding percentage of extraction was 22.7% and specific activity was 78.9 N-benzoyl-L-arginlne ethyl ester （BAEE） U·mg^-1 protein, three times than that in crude pancreatin. There was no lipase and amylopsin activity was decreased to 1/5 of crude pancreatin. Partly purifying solution was treated by condition mentioned above with 0.05mol·L^-1 ceryl-trimethyl-ammonium bromide （CTAB）, total extraction percentage of trypsin was 74.18% and specific activity was 3148.3 BAEE U·mg^-1, i.e. 48.16 times purer than that in crude pancreatin. Through sodium dodecyl sulfate-polyacryl amide gel electrophoresis （SDS-PAGE） and image analysis of extracted product, there were only three bands in the trypsin, while seven in crude pancreatin, and electrophoresis location of main bend was almost identical with the standard enzyme.展开更多
The pepsin and trypsin activities and some of the properties of the two enzymes of southern sheatfish larvae were studied. The results were as follows: the highest level of trypsin activity is in the foregut in all...The pepsin and trypsin activities and some of the properties of the two enzymes of southern sheatfish larvae were studied. The results were as follows: the highest level of trypsin activity is in the foregut in all measured tissues; from foregut to hindgut, trypsin activities decrease; the pH optimum of trypsin activity is pH9.0; the strongest pepsin activity is in the stomach; the proper density of haemoglobin for detecting pepsin activity is 1.0%. These data are useful in solving applied nutritional problems, such as the adequacy of artificial food to the digestive abilities of the fish.展开更多
AIM: To investigate whether matrix metalloproteinases-9 (MMP-9) or trypsinogens could serve as histological markers for an aggressive disease course in pediatric ulcerative colitis (UC). METHODS: We identified 24 pati...AIM: To investigate whether matrix metalloproteinases-9 (MMP-9) or trypsinogens could serve as histological markers for an aggressive disease course in pediatric ulcerative colitis (UC). METHODS: We identified 24 patients with pediatric onset (≤ 16 years) UC who had undergone surgery during childhood/adolescence a median of 2.1 years (range 0.1-7.4 years) after the diagnosis (between 1990 and 2008) in Children's Hospital, Helsinki, Finland. We also identified 27 conservatively treated UC patients and matched them based on their age at the time of diagnosis and follow-up at a median of 6 years (range 3-11 years) to serve as disease controls. Twenty children for whom inflammatory bowel disease (IBD) had been excluded as a result of endoscopy served as non-IBD controls. Colon biopsies taken by diagnostic endoscopy before the onset of therapy were stained using immunohistochemistry to study the expression of MMP-9, trypsinogen-1 (Tryp-1), Tryp-2, and a trypsin inhibitor (TATI). The profiles of these proteases and inhibitor at diagnosis were compared between the surgery group, the conservatively treated UC patients and the non-IBD controls. RESULTS: The proportions of Tryp-1 and Tryp-2 positive samples in the colon epithelium and in the inflammatory cells of the colon stroma were comparable between the studied groups at diagnosis. Interestingly, the immunopositivity of Tryp-1 (median 1; range 0-3) was significantly lower in the epithelium of the colon in the pediatric UC patients undergoing surgery when compared to that of the conservatively treated UC patients (median 2; range 0-3; P = 0.03) and non-IBD controls (median 2; range 0-3; P = 0.04). For Tryp-2, there was no such difference. In the inflammatory cells of the colon stroma, the immunopositivities of Tryp-1 and Tryp-2 were comparable between the studied groups at diagnosis. Also, the proportion of samples positive for TATI, as well as the immunopositivity, was comparable between the studied groups in the colon epithelium. In the stromal inflammatory cells of the colon, TATI was not detected. In UC patients, there were significantly more MMP-9 positive samples and a higher immunopositivity in the stromal inflammatory cells of the colon when compared to the samples from the non-IBD patients (P = 0.006 and P = 0.002, respectively); the immunopositivity correlated with the histological grade of inflammation (95%CI: 0.22-0.62; P = 0.0002), but not with the other markers of active disease. There were no differences in the immunopositivity or in the proportions of MMP-9 positive samples when examined by epithelial staining. The staining profiles in the ileal biopsies were comparable between the studied groups for all of the studied markers.CONCLUSION: For pediatric UC patients who require surgery, the immunopositivity of Tryp-1 at diagnosis is lower when compared to that of patients with a more benign disease course.展开更多
Herein,we report a novel sensor to detect trypsin using a purpose-designed fluorescein-labelled peptide with negatively charged carbon nanoparticles(CNPs)modified by acid oxidation.The fluorescence of the fluorescein-...Herein,we report a novel sensor to detect trypsin using a purpose-designed fluorescein-labelled peptide with negatively charged carbon nanoparticles(CNPs)modified by acid oxidation.The fluorescence of the fluorescein-labelled peptide was quenched by CNPs.The sensor reacted with trypsin to cleave the peptide,resulting in the release of the dye moiety and a substantial increase in fluorescence intensity,which was dose-and time-dependent,and trypsin could be quantified accordingly.Correspondingly,the biosensor has led to the development of a convenient and efficient fluorescent method to measure trypsin activity,with a detection limit of 0.7 mg/mL.The method allows rapid determination of trypsin activity in the normal and acute pancreatitis range,suitable for point-of-care testing.Furthermore,the applicability of the method has been demonstrated by detecting trypsin in spiked urine samples.展开更多
基金Supported by the National Natural Science Foundation of China,No.82073908.
文摘BACKGROUND Endogenous regeneration of pancreatic isletβ-cells is a path to cure both type 1 and advanced type 2 diabetes.Pancreatic cancer cell line-1(PANC-1),a human pancreatic islet progenitor cell line,can be induced by trypsin to differentiate into insulin-secreting islet-like aggregates(ILAs).However,the underlying mechanism has not been explored.AIM To explore the mechanism and signaling pathway of trypsin-induced differentiation of islet progenitor cells into insulin-secreting cells.METHODS PANC-1 cells were induced by trypsin to form ILAs and differentiate into insulinsecreting cells.Clustered regularly interspaced short palindromic repeats(CRISPR)-associated protein 9 knockout and small interfering RNA knockdown techniques were used to investigate membrane proteins and downstream signaling pathways involved in the process.RESULTS The extracellular domain of membrane receptor E-cadherin hydrolyzed by trypsin induced the aggregation of PANC-1 cells and stimulated E-cadherin-recruited casein kinase-1γ3,which specifically phosphorylated the Ser655/Thr658 site ofα-catenin in the cadherin-catenin complex,participating in the process of PANC-1 differentiation and affecting the maturation of differentiated ILAs.CONCLUSION The current study reveals the mechanism by which trypsin promotes PANC-1 cell differentiation into islet-like cells,providing a novel approach for endogenous isletβ-cell regeneration.
基金supported by the Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety(No.GDPKLAPPS2005)the School Level Talent Project of Lingnan Normal University(No.ZL2021009)+2 种基金the Science and Technology Planning Project of Zhanjiang(No.2020A01040)the Study on the Preparation of Active Polypeptide from the Processing Waste of White Shrimp and its Fatigue Resistance(No.2021E05022)the Scientific Research Capacity Improvement Project of the Key Construction Discipline of Guangdong Province(No.2022ZD JS079).
文摘During postmortem storage,fluoride in Antarctic krill can be enriched in the muscle.Trypsin,as the most important digestive enzyme in Antarctic krill with a high activity in low temperature,plays a potential role in this process.In this study,endogenous trypsin was purified and its properties were investigated.The involvement of trypsin in the generation of free fluoride from Antarctic krill cuticle was explored.Cuticle microstructure before and after hydrolysis was compared with scanning electron microscopy,and the ash samples of the hydrolyzed Antarctic krill cuticle were analyzed with X-ray diffraction,Fourier transform infrared spectroscopy,and electron dispersive spectroscopy,respectively.Mass spectrometry analysis and inhibition tests confirmed that the purified enzyme was endogenous trypsin.Results of the present study indicated that trypsin digestion caused the increases of the concentrations of both fluoride ions and free amino N simultaneously,while the protein coated on the cuticle surface was dissolved too.However,no compositional change was detected in the cuticle inorganic salts.These findings suggest that trypsin triggered free fluoride release from Antarctic krill cuticle.In addition,the kinetics of free fluoride release could be described by the equation C_(W)=(1-0.97^(-0.006t)-0.03e^(0.0558t))×337.53+10.50.The present study improved the understanding of the role of trypsin in free fluoride release from Antarctic krill cuticle,facilitating future studies aimed at reducing the fluoride content in krill protein during Antarctic krill processing.
基金supported by the National Natural Science Foundation of China(21808020)the Applied Basic Research Program of Science&Technology Department of Sichuan Province(2018JY0151)。
文摘Phlorizin(PHL)is a natural compound with strong antioxidant properties mainly found in apples.In this paper,the interaction mechanism of PHL with pepsin and trypsin was comparatively evaluated by computer simulation,fluorescence spectra,circular dichroism(CD),and Fourier transform infrared(FT-IR)spectra at a molecular level.Fluorescence spectra showed that PHL quenches the pepsin/trypsin by static quenching.Thermodynamic parameters indicated that PHL binds to pepsin mainly through hydrogen bonds and van der Waals forces,and that of trypsin was electrostatic forces.The ground state complexes PHL and protease have a moderate affinity of 105 L/mol PHL binds more strongly to trypsin than to pepsin.CD and FT-IR spectra results showed that pepsin/trypsin decreased theβ-sheet content and slightly changed its secondary structure upon PHL.These experimental results are mutually verified with the predicted computer-aid simulation results.Upon PHL and trypsin binding,the antioxidant capacity of PHL was elevated.Nevertheless,the antioxidant capacity of PHL was decreased after binding to pepsin.This work elucidates the binding of PHL binding mechanisms to pepsin/trypsin and provides useful information for the digestion of PHL to improve the application of PHL in food processing.
基金Supported by the Joint Construction Project of Henan Medical Science and Technology(No.LHGJ20220370)the Natural Science Foundation of Henan Province(No.232300420237).
文摘AIM:To compare the safety and clinical outcomes of subconjunctival trypsin and dexamethasone(DEX)injections in the treatment of anterior chamber fibrin exudates in eyes with globe rupture following primary wound repair and vitrectomy.METHODS:A retrospective analysis included 42 males and 10 females(mean age 46.0±6.0y,range 34 to 58y)who underwent primary wound sutures and vitrectomy for globe rupture.Patients with pupil-covered fibrinous exudate or/and membrane in the anterior chamber were treated.On the first postoperative day,subconjunctival injections of either 5000 units(0.4 mL)of trypsin solution(n=25)or 0.5 mL(1 mg)DEX(n=27)were administered to accelerate exudate absorption.Efficacy was assessed by observing break time and partial absorption of the fibrin exudate membrane.Safety and comfort were evaluated by monitoring intraocular pressure(IOP),allergy,pain,and foreign body sensation.RESULTS:Both groups achieved 1/3 absorption of the anterior chamber fibrin exudate membrane,but the trypsin group exhibited shorter break time and partial absorption time compared to the DEX group(P<0.05).Trypsin treatment was also less irritating to patients.No adverse reactions were reported,and IOP remained stable.Visual acuity improved in both groups without statistical difference.CONCLUSION:Compared to DEX,trypsin demonstrates a shorter absorption time for the fibrin exudate membrane with a more comfortable process in treating pupil-covered fibrinous exudate or/and membrane after vitrectomy for globe rupture.
基金The authors appreciate the support from the Zhe-jiang Province Lingyan Key R&D Project(No.2022C01177)the Zhejiang Administration for Market Regulation Eyas Program Cultiva-tion Project(No.CY2022355).
文摘Herein,a novel method for fl uorometric detection of soybean trypsin inhibitor(SBTI)activity based on a water-soluble poly(diphenylacetylene)derivative was reported.Fluorescence quenching of the polymer via p-nitroaniline,produced from the trypsin-catalyzed decomposition of N-benzoyl-DL-arginine-4-nitroanilide hydrochloride(L-BAPA),was well described using the Stern-Volmer equation.SBTI activity was quantitatively assessed based on changes in the fl uorescence intensity of the polymer.This strategy has several advantages,such as high sensitivity and ease of operation.Moreover,its applicability to other biochemical analyses is promising.
基金This work was supported by the National Key Research and Development Program of China(2017YFC1600802)the National and Local Joint Engineering Laboratory of High Efficiency and Superior-Quality Cultivation and Fruit Deep Processing Technology of Characteristic Fruit Trees in South Xinjiang of China(No.FE202303).
文摘During post-harvest storage of Cucumis sativus fruit,the application of trypsin treatment could increaseflavonoid compound levels and reduce oxidative damage.To investigate the mechanism of trypsin-inducedflavonoid bio-synthesis in C.sativus,we conducted a combined analysis of transcriptomics and widely targeted metabolomics.One hundred and seventy-five significantly different metabolites were obtained from metabolomics data.The kyoto encyclopedia of genes and genomes(KEGG)functional enrichment results indicated that these metabolites were mainly involved in the phenylpropanoid biosynthesis pathway.By combining the results of the weighted gene co-expression network analysis(WGCNA)with the 130 upregulated phenylpropanoid metabolites,22 significantly upregulated phenylpropanoid metabolites were identified.Trilobatin was identified as the most prominent meta-bolite through cluster analysis and variable importance in projection(VIP)analysis.High performance liquid chro-matography(HPLC)experiments confirmed that trilobatin was the key metabolite induced by trypsin.The transcriptomic results showed that 1068 genes in the brown module of WGCNA were highly positively correlated withflavonoid biosynthesis.The gene set enrichment analysis(GSEA)identified leading edges in 4 key KEGG path-ways.Finally,combined with WGCNA and GSEA analysis results,35 core genes were obtained.The co-expression network of transcriptomics and metabolomics suggested that CsWRKY28 and CsMYC2 regulated the biosynthesis of trilobatin.The quantitative real-time polymerase chain reaction(RT-qPCR)and dual luciferase experiments con-firmed the activation effect of CsWRKY28 on CsMYC2 and downstream target genes.This study revealed the key transcription factors involved in the trypsin-controlled biosynthesis of trilobatin in C.sativus and provided a new theoretical basis for elucidating the molecular mechanism of trypsin preservation.
基金the National Key Research and Development Program of China(2017YFC1600802).
文摘Trypsin,a novel superoxide scavenger,significantly enhances the storage quality of Hylocereus undatus(H.undatus).To elucidate the preservation mechanism of trypsin on H.undatus,a widely targeted metabolomic analysis,and transcriptomics analysis were conducted.Firstly,a total of 453 metabolites were identified,with organic acids and their derivatives constituting the largest proportion(25%).Amino acids and their metabolites,prominent among organic acids,were further analyzed.Among them,73 metabolites were associated with amino acids,and 37 exhibited significant differences.The most enriched Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway was arginine biosynthesis(map00220),with polyamine metabolites showing the most pronounced differences,particularly spermine(FC=1.7594).Compared with the control group,4-hydroxy-2-oxoglutaric acid was significantly upregulated(FC=2.117)in the process of spermine biosynthesis.Furthermore,the results of Gene Ontology(GO)and KEGG enrichment analysis of the H.undatus transcriptome profile revealed that trypsin treatment led to 187 differentially expressed genes associated with arginine.Both GO and KEGG analyses exhibited significant enrichment in the spermine biosynthetic process(GO:0006597)(map:00220)within the arginine biosynthesis pathway.Moreover,most enzymes and metabolites within the spermine biosynthesis pathway in H.undatus were upregulated.The results of the PPI network highlighted that ADC,SPDS,and SAMDC,among others,were pivotal proteins involved in trypsin-regulated arginine metabolism and spermine synthesis.This study revealed that trypsin could significantly delay postharvest senescence of H.undatus at room temperature.This effect might be attributed to trypsin triggering the synthesis of 4-hydroxy-2-oxoglutaric acid in the fruit peel,thereby promoting the biosynthesis of spermine and other polyamines.
基金National Natural Science Foundation of China (Grant No 30873405)National Drug Innovation Program(Grant No.2009ZX09301-011)
文摘A reliable and validated HPLC method was established for the assay of trypsin inhibitors（TI）and it was used in the investigation of the active TI components inMomordica cochinchinensis（Cucurbitaceae family）.The underlying principle of the assay is the measurement of the decrease in trypsin activity due to the presence of TI in analyzed samples,which was achieved by using HPLC separation and quantification of p-nitroanilide that was generated by tryptic hydrolysis of N-α-benzoyl-DL-arginine -4-nitroanilide.The results showed that the HPLC method had higher selectivity than conventional spectrophotometric assay.
文摘By 30% - 60% (NH4)(2)SO4 fractional precipitation, anion-exchange chromatography on DEAE-Sepharose CL-6B, gel filtration on Sephacryl S-200 and anion-exchange chromatography on Waters AP-1 column (Protein(PM)-Pak DEAE 15HR), a proteinase which can inactivate soybean trypsin inhibitor (STI) was purified from mung bean ( Vigna rabiata (L.) Wilezek) sprouts. Its molecular weight was estimated to be 29.8 kD by SDS-PAGE, and its K-m and V-max for STI were 769.2 N-alpha -benzoyl-L-arginine ethyl ester BAEE/mL and 115.3 BAEE . mL(-1) . min(-1) respectively. This proteinase was stable at temperatures lower than 50 degreesC and pH 6.5 - 8.5, and 90.91% STI activity of defatted soybean powder was inactivated by this preparation, with proteolytic activity 5 000 BAEE/mL at 50 degreesC and pH 8.0 in 4 h.
基金Supported by the NNSF of China (No.30670227)hanghai Agricultural Science & Technology Key Grant [6-1(2006)].
文摘Abstract The digestive enzyme activity and mRNA level of trypsin during the embryonic development of Cherax quadricarinatus were analyzed using biochemical and Fluorogenic Quantitative PCR （FQ-PCR） methods. The results show that the activities of trypsin and chymotrypsin had two different change patterns. Trypsin specific activity increased rapidly in the early stages of development and still remained high in preparation for the hatch stage. However, chymotrypsin activity peaked in stage 4 of embryonic development and decreased significantly in the last stage. The mRNA level of trypsin was elevated in all stages and two peak values were observed in stages 2 and 5 respectively. The results indicate that trypsin is very important for the utilization of the yolk during embryonic development and for the assimilation of dietary protein for larvae. The gene of trypsin is probably regulated at transcriptional level. The mRNA levels of trypsin can reflect not only trypsin activity, but also the regulatory mechanism for expression of trypsin gene to a certain degree.
基金The work is partially supported by the National Natural Science Foundation of China(20277031).
文摘Macroporous cross-linking chitosan layer coated on silica gel （CTS-SiO2） was prepared by phase inversion and polyethylene glycol （PEG）molecular imprinting methods. Formation of macroporous surtace was investigated by scanning electron microscopy （SEM） and BET analysis.The prepared bead was activated by reacting with 1,2-ethylene digiycidyl ether for introducing epoxy groups, and trypsin could be efficiently immobilized on the bead as a biospecific ligand.The bead bearing trypsin was employed to purify trypsin inhibitor （TIs） from egg white as affinity adsorbent.
文摘SDS-PAGE was applied to determine trypsin activity and inhibition. After the hydrolysis by trypsin to substrate bovine serum albulnin (BSA) under different temperatures and pH, the hydrolysis degree of BSA was conducted using SDS-PAGE. From the quantitative analysis to the electrophoresis bands of BSA and its hydrolysis products in SDS-PAGE pattern, the change of trypsin activity was determined, and then the optimum temperature at 40°C and the optimum pH at pH 8.5 - 8.7 for trypsin activity were obtained. All the target bonds in BSA molecule could be hydrolyzed at the same time by trypsin. The inhibition was due to the binding of inhibitor to trypsin, which made it impossible for trypsin to touch the substrate protein. SDS-PAGE was demonstrated to be also an effect method for assaying the characteristics of trypsin activity and its inhibition.
基金supported by a research project of the Science and Technology Key Group in Zhejiang Provincethe research projects from the Science and Technology Department of Zhejiang Province,China (2009C12068)
文摘The aim of the present study was to optimize trypsin inhibitor degradation in soybean meal by solid-state fermentation （SSF） with Lactobacillus brevis and Aspergillus oryzae, and to determine the effect of SSF on phytic acid, crude protein, crude fat, and amino acid profile. Response surface methodology （RSM） with Box-Behnken design was used to optimize SSF. The optimal conditions derived from RSM for L. brevis fermentation were： pH=5. 1; inoculum size=10%; duration=72 h; substrate to water ratio=1.5. The minimum content of trypsin inhibitors was 6.4 mg g^-1 dry matter. The optimal conditions derived from RSM for A. oryzae fermentation were： substrate to water ratio= 0.8 1; inoculum size=4%; duration=120 h. The minimum content of trypsin inhibitors was 1.6 mg g^-1 dry matter. Both L. brevis and A. oryzae decreased trypsin inhibitors dramatically （57.1 and 89.2% respectively）. L. brevis fermentation did not affect phytic acid （0.4%） and crude fat （5.2%） considerably, whereas A. oryzae fermentation degraded phytic acid （34.8%） and crude fat （22.0%） contents to a certain extent. Crude protein content was increased after both fermentation （6.4 and 12.9% for L. brevis and A. oryzae respectively）. Urease activity was reduced greatly （83.3 and 58.3% for L. brevis and A. oryzae respectively）. In conclusion, SSF with A. oryzae and L. brevis reduced trypsin inhibitor content and modified major macronutrients in soybean meal.
文摘BACKGROUND: Urinary trypsin inhibitor (UTI) inhibits the inflammatory response and protects against ischemia-reperfusion (I/R) injury. The inflammatory response is mediated by nuclear factor-kappa B (NF-kappa B) and its related target genes and products such as vascular endothelial cell adhesion molecule and CXC chemokines. We aimed to assess the roles of those mediators in a UTI-treated mouse model of hepatic I/R injury. METHODS: Treatment group 1 (UTI given 5 minutes prior to liver ischemia), treatment group 2 (UTI given 5 minutes after the anhepatic phase) and a control group were investigated. Blood and liver samples were obtained and compared at 1, 3, 6 and 24 hours after reperfusion. RESULTS: Attenuation of pathological hepatocellular damage was greater in the treatment groups than in the control group (P < 0.05). Compared with the control group, the UTI treatment groups showed significantly lower serum alanine aminotransferase and aspartate aminotransferase levels, decreased myeloperoxidase activity, and reduced NF-kappa B activation. Also downregulated was the expression of tumor necrosis factor-alpha, cytokine-induced neutrophil chemoattractant, and macrophage inflammatory protein-2 at the mRNA level. P-selectin protein and intercellular adhesion molecule-1 protein expression were also downregulated. In addition, the treatment group I showed a better protective effect against I/R injury than the treatment group 2. CONCLUSIONS: UTI reduces NF-kappa B activation and downregulates the expression of its related mediators, followed by the inhibition of neutrophil aggregation and infiltration in hepatic I/R injury. The protective role of UTI is more effective in prevention than in treatment.
基金Supported by the Medical University of Bialystok within the Project #30-12770
文摘AIM: To assess the effect of non-selective ETA/B (LU 302872)and selective ETA (LU 302146) antagonist on pancreatic histology and ultrastructure of acinar cells in connection with trypsinogen activation in early caerulein-induced AP.METHODS: Male Wistar rats with caerulein-induced AP,lasting 4 h, were treated i.p. with 10 and 20 mg/kg b.w.of each antagonist. Edema, inflammatory infiltration,necrosis and vacuolization of acinar cells in the pancreas were scored at 0-3 scale. Free active trypsin (FAT), total potential trypsin (TPT) after activation with enterokinase,and index of trypsinogen activation (%FAT/TPT) were assayed in pancreatic homogenates.RESULTS: In untreated AP, the edema, inflammatory infiltration, necrosis and vacuolization increased as compared to control healthy rats (P＜0.01). None of the treatment exerted any meaningful effect on the edema and inflammatory infiltration. The selective antagonist increased slightly the necrosis score to 0.82±0.06 at higher dose (P＜0.05) vs 0.58±0.06 in untreated AP. The nonselective antagonist increased slightly the vacuolization score to 2.41±0.07 at higher dose (P＜0.01) vs 1.88±0.08in untreated AP. The decrease in the number of zymogen granules, disorganization of endoplasmic reticulum,autophagosomes and cytoplasmic vacuoles were more prominent in treated AP than in untreated AP groups.%FAT/TPT in untreated AP increased about four times (18.4±3.8 vs4.8±1.3 in control group without AP, P＜0.001).Treatment of AP with both antagonists did not affect significantly augmented trypsinogen activation.CONCLUSION: The treatment with endothelin-1 receptors (non-selective ETA/B and selective ETA) antagonists has essential effect neither on the edema and inflammatory infiltration nor on trypsinogen activation observed in the early course of caerulein-induced AP. Nevertheless a slight increase of the necrosis and vacuolization score and some of the ultrastructural data could suggest the possibility of their undesired effects in caerulein-induced AP at investigated doses.
文摘In this article, the influence factors of trypsin extracted from crude pancreatin was investigated, and scanning turmeling microscope（STM） was used to observe the image of trypsin in butane-diacid-2-ethyl-hexyl-ester-sulfonic sodium （AOT）/iso-octane reversed micelles. The STM image showed that trypsins bounded in reversed micelles was rigid, which weakened its conjugative effect and caused maximum ultraviolet absorption and fluorescence emissive absorption moving toward blue waves. AOT concentration, pH and cations were the main influence factors of extraction. Specifically, extraction percentage of trypsin decreased with the increase of AOT concentration from 0.01 to 0.1mol·L^-1. When pH value is from 5.30 to 10.0, i.e. less than pI of trypsin, the extraction percentage is raised with the different increase of pI-pH, but when the pH value is less than 5.20, the extraction percentage is decreased with the acidity added. Besides, the extraction efficiency is negative, related with the concentrations of Ca^2＋, Na^＋, K^＋ which were in the range of 0.2-1.0mol.L^-1, and influence of concentration of Ca^2＋ is greater than that of Na^＋, and K^＋ which has the minimum impact with the same concentration. Finally, optimum conditions to extract trypsin were： AOT reversed micelles 0.05mol·L^-1, trypsin concentration in crude pancreatin solution 3mg·ml^-1, pH 5.2-- 5.3, ratio （by volume） of extraction phase to strip-extraction phase 1 ： 1, and time of 5min. The corresponding percentage of extraction was 22.7% and specific activity was 78.9 N-benzoyl-L-arginlne ethyl ester （BAEE） U·mg^-1 protein, three times than that in crude pancreatin. There was no lipase and amylopsin activity was decreased to 1/5 of crude pancreatin. Partly purifying solution was treated by condition mentioned above with 0.05mol·L^-1 ceryl-trimethyl-ammonium bromide （CTAB）, total extraction percentage of trypsin was 74.18% and specific activity was 3148.3 BAEE U·mg^-1, i.e. 48.16 times purer than that in crude pancreatin. Through sodium dodecyl sulfate-polyacryl amide gel electrophoresis （SDS-PAGE） and image analysis of extracted product, there were only three bands in the trypsin, while seven in crude pancreatin, and electrophoresis location of main bend was almost identical with the standard enzyme.
文摘The pepsin and trypsin activities and some of the properties of the two enzymes of southern sheatfish larvae were studied. The results were as follows: the highest level of trypsin activity is in the foregut in all measured tissues; from foregut to hindgut, trypsin activities decrease; the pH optimum of trypsin activity is pH9.0; the strongest pepsin activity is in the stomach; the proper density of haemoglobin for detecting pepsin activity is 1.0%. These data are useful in solving applied nutritional problems, such as the adequacy of artificial food to the digestive abilities of the fish.
基金Supported by Pivikki and Sakari Sohlberg Foundation, to Piekkala MHelsinki University Central Hospital Grant, to Kolho KLthe Finnish Pediatric Research Foundation, to Kolho KL
文摘AIM: To investigate whether matrix metalloproteinases-9 (MMP-9) or trypsinogens could serve as histological markers for an aggressive disease course in pediatric ulcerative colitis (UC). METHODS: We identified 24 patients with pediatric onset (≤ 16 years) UC who had undergone surgery during childhood/adolescence a median of 2.1 years (range 0.1-7.4 years) after the diagnosis (between 1990 and 2008) in Children's Hospital, Helsinki, Finland. We also identified 27 conservatively treated UC patients and matched them based on their age at the time of diagnosis and follow-up at a median of 6 years (range 3-11 years) to serve as disease controls. Twenty children for whom inflammatory bowel disease (IBD) had been excluded as a result of endoscopy served as non-IBD controls. Colon biopsies taken by diagnostic endoscopy before the onset of therapy were stained using immunohistochemistry to study the expression of MMP-9, trypsinogen-1 (Tryp-1), Tryp-2, and a trypsin inhibitor (TATI). The profiles of these proteases and inhibitor at diagnosis were compared between the surgery group, the conservatively treated UC patients and the non-IBD controls. RESULTS: The proportions of Tryp-1 and Tryp-2 positive samples in the colon epithelium and in the inflammatory cells of the colon stroma were comparable between the studied groups at diagnosis. Interestingly, the immunopositivity of Tryp-1 (median 1; range 0-3) was significantly lower in the epithelium of the colon in the pediatric UC patients undergoing surgery when compared to that of the conservatively treated UC patients (median 2; range 0-3; P = 0.03) and non-IBD controls (median 2; range 0-3; P = 0.04). For Tryp-2, there was no such difference. In the inflammatory cells of the colon stroma, the immunopositivities of Tryp-1 and Tryp-2 were comparable between the studied groups at diagnosis. Also, the proportion of samples positive for TATI, as well as the immunopositivity, was comparable between the studied groups in the colon epithelium. In the stromal inflammatory cells of the colon, TATI was not detected. In UC patients, there were significantly more MMP-9 positive samples and a higher immunopositivity in the stromal inflammatory cells of the colon when compared to the samples from the non-IBD patients (P = 0.006 and P = 0.002, respectively); the immunopositivity correlated with the histological grade of inflammation (95%CI: 0.22-0.62; P = 0.0002), but not with the other markers of active disease. There were no differences in the immunopositivity or in the proportions of MMP-9 positive samples when examined by epithelial staining. The staining profiles in the ileal biopsies were comparable between the studied groups for all of the studied markers.CONCLUSION: For pediatric UC patients who require surgery, the immunopositivity of Tryp-1 at diagnosis is lower when compared to that of patients with a more benign disease course.
文摘Herein,we report a novel sensor to detect trypsin using a purpose-designed fluorescein-labelled peptide with negatively charged carbon nanoparticles(CNPs)modified by acid oxidation.The fluorescence of the fluorescein-labelled peptide was quenched by CNPs.The sensor reacted with trypsin to cleave the peptide,resulting in the release of the dye moiety and a substantial increase in fluorescence intensity,which was dose-and time-dependent,and trypsin could be quantified accordingly.Correspondingly,the biosensor has led to the development of a convenient and efficient fluorescent method to measure trypsin activity,with a detection limit of 0.7 mg/mL.The method allows rapid determination of trypsin activity in the normal and acute pancreatitis range,suitable for point-of-care testing.Furthermore,the applicability of the method has been demonstrated by detecting trypsin in spiked urine samples.
