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Food Research International (Ottawa,... Jul 2024Oral delivery of larger bioactive peptides (>20 amino acids) to the small intestine remains a challenge due to their sensitivity to proteolytic degradation and chemical...
Oral delivery of larger bioactive peptides (>20 amino acids) to the small intestine remains a challenge due to their sensitivity to proteolytic degradation and chemical denaturation during gastrointestinal transit. In this study, we investigated the capacity of crosslinked alginate microcapsules (CLAMs) formed by spray drying to protect Plantaricin EF (PlnEF) (C-EF) in gastric conditions and to dissolve and release PlnEF in the small intestine. PlnEF is an unmodified, two-peptide (PlnE: 33 amino acids; PlnF: 34 amino acids) bacteriocin produced by Lactiplantibacillus plantarum with antimicrobial and gut barrier protective properties. After 2 h incubation in simulated gastric fluid (SGF) (pH 1.5), 43.39 % ± 8.27 % intact PlnEF was liberated from the CLAMs encapsulates, as determined by an antimicrobial activity assay. Transfer of the undissolved fraction to simulated intestinal fluid (SIF) (pH 7) for another 2 h incubation resulted in an additional release of 16.13 % ± 4.33 %. No active PlnEF was found during SGF or sequential SIF incubations when pepsin (2,000 U/ml) was added to the SGF. To test PlnEF release in C-EF contained in a food matrix, C-EF was mixed in peanut butter (PB) (0.15 g C-EF in 1.5 g PB). A total of 12.52 % ± 9.09 % active PlnEF was detected after incubation of PB + C-EF in SGF without pepsin, whereas no activity was found when pepsin was included. Transfer of the remaining PB + C-EF fractions to SIF yielded the recovery of 46.67 % ± 13.09 % and 39.42 % ± 11.53 % active PlnEF in the SIF following exposure to SGF and to SGF with pepsin, respectively. Upon accounting for the undissolved fraction after SIF incubation, PlnEF was fully protected in the CLAMs-PB mixture and there was not a significant reduction in active PlnEF when pepsin was present. These results show that CLAMs alone do not guard PlnEF bacteriocin peptides from gastric conditions, however, mixing them in PB protected against proteolysis and improved intestinal release.
Topics: Alginates; Bacteriocins; Capsules; Peptides; Intestine, Small; Lactobacillus plantarum; Hydrogen-Ion Concentration; Cross-Linking Reagents; Pepsin A
PubMed: 38823837
DOI: 10.1016/j.foodres.2024.114473 -
World Journal of Gastroenterology May 2024Heartburn is a common symptom shared by both gastroesophageal reflux disease (GERD) and functional heartburn (FHB), which can make it challenging to differentiate...
Heartburn is a common symptom shared by both gastroesophageal reflux disease (GERD) and functional heartburn (FHB), which can make it challenging to differentiate between the two conditions. However, examining oral manifestations of GERD can be a cost-effective and readily available method to aid in this differentiation process. It may serve as a valuable tool in distinguishing GERD from FHB.
Topics: Humans; Gastroesophageal Reflux; Saliva; Heartburn; Pepsin A; Diagnosis, Differential; Biomarkers
PubMed: 38817654
DOI: 10.3748/wjg.v30.i19.2612 -
Journal of Nutritional Science and... 2024The Ussing chamber is a tool for analyzing drug absorption. We investigated whether the Ussing chamber can be used to analyze the process from digestion to absorption of...
The Ussing chamber is a tool for analyzing drug absorption. We investigated whether the Ussing chamber can be used to analyze the process from digestion to absorption of protein in the gastrointestinal tract. Mixtures containing infant formula, whole cow's milk, processed soy milk, enteral nutrition, or human breast milk, were placed in the apical membrane side equipped with Caco-2 cells. After the addition of first pepsin then pancreatin, samples from the apical and basal membranes were collected. Infant formula showed the highest digestibility and absorption rate. This may be attributed to the presence of whey protein, which is rapidly digested and absorbed. The digestion and absorption of human breast milk showed different results in each donor, suggesting that digestion and absorption may vary among individuals. We concluded that the Ussing chamber can continuously analyze the process from digestion to absorption of proteins in the gastrointestinal tract.
Topics: Digestion; Humans; Caco-2 Cells; Gastrointestinal Tract; Milk, Human; Infant Formula; Animals; Intestinal Absorption; Whey Proteins; Milk Proteins; Milk; Dietary Proteins; Enteral Nutrition; Soy Milk; Infant; Pepsin A
PubMed: 38684386
DOI: 10.3177/jnsv.70.158 -
Ecotoxicology and Environmental Safety May 2024To study the heavy metal accumulation and its impact on insect exterior and chromosome morphology, and reveal the molecular mechanism of insects adapting to long-term...
To study the heavy metal accumulation and its impact on insect exterior and chromosome morphology, and reveal the molecular mechanism of insects adapting to long-term heavy metal compound pollution habitats, this study, in the Diaojiang river basin, which has been polluted by heavy metals(HMs) for nearly a thousand years, two Eucriotettix oculatus populations was collected from mining and non-mining areas. It was found that the contents of 7 heavy metals (As, Cd, Pb, Zn, Cu, Sn, Sb) in E. oculatus of the mining area were higher than that in the non-mining 1-11 times. The analysis of morphology shows that the external morphology, the hind wing type and the chromosomal morphology of E. oculatus are significant differences between the two populations. Based on the heavy metal accumulation,morphological change, and stable population density, it is inferred that the mining area population has been affected by heavy metals and has adapted to the environment of heavy metals pollution. Then, by analyzing the transcriptome of the two populations, it was found that the digestion, immunity, excretion, endocrine, nerve, circulation, reproductive and other systems and lysosomes, endoplasmic reticulum and other cell structure-related gene expression were suppressed. This shows that the functions of the above-mentioned related systems of E. oculatus are inhibited by heavy metal stress. However, it has also been found that through the significant up-regulation of genes related to the above system, such as ATP2B, pepsin A, ubiquitin, AQP1, ACOX, ATPeV0A, SEC61A, CANX, ALDH7A1, DLD, aceE, Hsp40, and catalase, etc., and the down-regulation of MAPK signalling pathway genes, can enhanced nutrient absorption, improve energy metabolism, repair damaged cells and degrade abnormal proteins, maintain the stability of cells and systems, and resist heavy metal damage so that E. oculatus can adapt to the environment of heavy metal pollution for a long time.
Topics: Animals; Metals, Heavy; Water Pollutants, Chemical; Grasshoppers; Environmental Monitoring; Mining; China; Adaptation, Physiological; Transcriptome; Rivers
PubMed: 38599159
DOI: 10.1016/j.ecoenv.2024.116301 -
Molecules (Basel, Switzerland) Mar 2024Pepsin, trypsin and proteinase K were used in the present study to hydrolyse the proteins from whole eggs, yolks or whites, and the resulting hydrolysates were...
Pepsin, trypsin and proteinase K were used in the present study to hydrolyse the proteins from whole eggs, yolks or whites, and the resulting hydrolysates were characterised in terms of antioxidant and IgE-binding properties, using a combination of in vitro and in silico methods. Based on the degree of hydrolysis (DH) results, the egg yolk proteins are better substrates for all the tested enzymes (DH of 6.2-20.1%) compared to those from egg whites (DH of 2.0-4.4%). The SDS-PAGE analysis indicated that pepsin and proteinase K were more efficient compared to trypsin in breaking the intramolecular peptide bonds of the high molecular weight egg proteins. For all the tested substrates, enzyme-assisted hydrolysis resulted in a significant increase in antioxidant activity, suggesting that many bioactive peptides are encrypted in inactive forms in the parent proteins. The hydrolysates obtained with proteinase K exhibited the highest DPPH radical scavenging activity (124-311 µM Trolox/g protein) and the lowest residual IgE-binding capacity. The bioinformatics tools revealed that proteinase K is able to break the integrity of the main linear IgE-binding epitopes from ovalbumin and ovomucoid. It can be concluded that proteinase K is a promising tool for modulating the intrinsic properties of egg proteins.
Topics: Antioxidants; Pepsin A; Trypsin; Endopeptidase K; Peptides; Egg Proteins; Hydrolysis; Immunoglobulin E; Protein Hydrolysates
PubMed: 38542963
DOI: 10.3390/molecules29061327 -
Biosensors Mar 2024Two fluorescent molecularly imprinted polymers (MIPs) were developed for pepsin enzyme utilising fluorescein and rhodamine b. The main difference between both dyes is...
Two fluorescent molecularly imprinted polymers (MIPs) were developed for pepsin enzyme utilising fluorescein and rhodamine b. The main difference between both dyes is the presence of two (diethylamino) groups in the structure of rhodamine b. Consequently, we wanted to investigate the effect of these functional groups on the selectivity and sensitivity of the resulting MIPs. Therefore, two silica-based MIPs for pepsin enzyme were developed using 3-aminopropyltriethoxysilane as a functional monomer and tetraethyl orthosilicate as a crosslinker to achieve a one-pot synthesis. Results of our study revealed that rhodamine b dyed MIPs (RMIPs) showed stronger binding, indicated by a higher binding capacity value of 256 mg g compared to 217 mg g for fluorescein dyed MIPs (FMIPs). Moreover, RMIPs showed superior sensitivity in the detection and quantitation of pepsin with a linear range from 0.28 to 42.85 µmol L and a limit of detection (LOD) as low as 0.11 µmol L. In contrast, FMIPs covered a narrower range from 0.71 to 35.71 µmol L, and the LOD value reached 0.34 µmol L, which is three times less sensitive than RMIPs. Finally, the developed FMIPs and RMIPs were applied to a separation-free quantification system for pepsin in saliva samples without interference from any cross-reactors.
Topics: Pepsin A; Limit of Detection; Fluorescein; Coloring Agents; Molecular Imprinting
PubMed: 38534258
DOI: 10.3390/bios14030151 -
Frontiers in Cellular and Infection... 2024Oral transmission of is probably the most frequent transmission mechanism in wild animals. This observation led to the hypothesis that consuming raw or undercooked meat...
INTRODUCTION
Oral transmission of is probably the most frequent transmission mechanism in wild animals. This observation led to the hypothesis that consuming raw or undercooked meat from animals infected with may be responsible for transmitting the infection. Therefore, the general objective of this study was to investigate host-pathogen interactions between the parasite and gastric mucosa and the role of meat consumption from infected animals in the oral transmission of
METHODS
Cell infectivity assays were performed on AGS cells in the presence or absence of mucin, and the roles of pepsin and acidic pH were determined. Moreover, groups of five female Balb/c mice were fed with muscle tissue obtained from mice in the acute phase of infection by the clone H510 C8C3 of , and the infection of the fed mice was monitored by a parasitemia curve. Similarly, we assessed the infective capacity of trypomastigotes and amastigotes by infecting groups of five mice Balb/c females, which were infected orally using a nasogastric probe, and the infection was monitored by a parasitemia curve. Finally, different trypomastigote and amastigote inoculums were used to determine their infective capacities. Adhesion assays of proteins to AGS stomach cells were performed, and the adhered proteins were detected by western blotting using monoclonal or polyclonal antibodies and by LC-MS/MS and bioinformatics analysis.
RESULTS
Trypomastigote migration in the presence of mucin was reduced by approximately 30%, whereas in the presence of mucin and pepsin at pH 3.5, only a small proportion of parasites were able to migrate (∼6%). Similarly, the ability of TCTs to infect AGS cells in the presence of mucin is reduced by approximately 20%. In all cases, 60-100% of the animals were fed meat from mice infected in the acute phase or infected with trypomastigotes or amastigotes developed high parasitemia, and 80% died around day 40 post-infection. The adhesion assay showed that cruzipain is a molecule of trypomastigotes and amastigotes that binds to AGS cells. LC-MS/MS and bioinformatics analysis, also confirmed that transialidase, cysteine proteinases, and gp63 may be involved in TCTs attachment or invasion of human stomach cells because they can potentially interact with different proteins in the human stomach mucosa. In addition, several human gastric mucins have cysteine protease cleavage sites.
DISCUSSION
Then, under our experimental conditions, consuming meat from infected animals in the acute phase allows the infection. Similarly, trypomastigotes and amastigotes could infect mice when administered orally, whereas cysteinyl proteinases and trans-sialidase appear to be relevant molecules in this infective process.
Topics: Female; Animals; Mice; Humans; Trypanosoma cruzi; Pepsin A; Parasitemia; Disease Models, Animal; Chromatography, Liquid; Tandem Mass Spectrometry; Chagas Disease; Mucins; Communicable Diseases
PubMed: 38495650
DOI: 10.3389/fcimb.2024.1297099 -
Cytokine Jun 2024Laryngopharyngeal reflux (LPR) is one of the most common disorders in otorhinolaryngology, affecting up to 10% of outpatients visiting otolaryngology departments. In...
BACKGROUND
Laryngopharyngeal reflux (LPR) is one of the most common disorders in otorhinolaryngology, affecting up to 10% of outpatients visiting otolaryngology departments. In addition, 50% of hoarseness cases are related to LPR. Pepsin reflux-induced aseptic inflammation is a major trigger of LPR; however, the underlying mechanisms are unclear. The nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome has become an important bridge between stimulation and sterile inflammation and is activated by intracellular reactive oxygen species (ROS) in response to danger signals, leading to an inflammatory cascade. In this study, we aimed to determine whether pepsin causes LPR-associated inflammatory injury via mediating inflammasome activation and explore the potential mechanism.
METHODS
We evaluated NLRP3 inflammasome expression and ROS in the laryngeal mucosa using immunofluorescence and immunohistochemistry. Laryngeal epithelial cells were exposed to pepsin and analyzed using flow cytometry, western blotting, and real-time quantitative PCR to determine ROS, NLRP3, and pro-inflammatorycytokine levels.
RESULTS
Pepsin expression was positively correlated with ROS as well as caspase-1 and IL-1β levels in laryngeal tissues. Intracellular ROS levels were elevated by increased pepsin concentrations, which were attenuated by apocynin (APO)-a ROS inhibitor-in vitro. Furthermore, pepsin significantly induced the mRNA and protein expression of thioredoxin-interacting protein, NLRP3, caspase-1, and IL-1β in a dose-dependent manner. APO and the NLRP3 inhibitor, MCC950, inhibited NLRP3 inflammasome formation and suppressed laryngeal epithelial cell damage.
CONCLUSION
Our findings verified that pepsin could regulate the NLRP3/IL-1β signaling pathway through ROS activation and further induce inflammatory injury in LPR. Targeting the ROS/NLRP3 inflammasome signaling pathway may help treat patients with LPR disease.
Topics: Humans; NLR Family, Pyrin Domain-Containing 3 Protein; Inflammasomes; Reactive Oxygen Species; Pepsin A; Laryngopharyngeal Reflux; Signal Transduction; Inflammation; Caspase 1; Interleukin-1beta
PubMed: 38471420
DOI: 10.1016/j.cyto.2024.156568 -
Journal of Agricultural and Food... Mar 2024Coffee is one of the most popular beverages around the world and its consumption contributes to the daily intake of dietary melanoidins. Despite the emerging...
Coffee is one of the most popular beverages around the world and its consumption contributes to the daily intake of dietary melanoidins. Despite the emerging physiological role of food melanoidins, their effect on digestive processes has not been studied so far. In this study, the activity of the gastrointestinal enzymes pepsin and trypsin was investigated in the presence of water-soluble coffee melanoidins. The gastric enzyme pepsin is only slightly affected, whereas the intestinal enzyme trypsin is severely inhibited by coffee melanoidins. The intestinal digestibility of casein was significantly inhibited by coffee melanoidins at a concentration achievable by regular coffee consumption. The inhibition of proteolytic enzymes by coffee melanoidins might decrease the nutritional value of dietary proteins.
Topics: Coffee; Pepsin A; Peptide Hydrolases; Trypsin; Dietary Proteins; Polymers
PubMed: 38456211
DOI: 10.1021/acs.jafc.3c09654 -
Marine Drugs Feb 2024The effects of ultrasonic power (0, 150, 300, 450, and 600 W) on the extraction yield and the structure and rheological properties of pepsin-soluble collagen (PSC) from...
The effects of ultrasonic power (0, 150, 300, 450, and 600 W) on the extraction yield and the structure and rheological properties of pepsin-soluble collagen (PSC) from albacore skin were investigated. Compared with the conventional pepsin extraction method, ultrasonic treatment (UPSC) significantly increased the extraction yield of collagen from albacore skin, with a maximum increase of 8.56%. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed that peptides of low molecular weight were produced when the ultrasonic power exceeded 300 W. Meanwhile, secondary structure, tertiary structure, and X-ray diffraction analyses showed that the original triple helix structure of collagen was intact after the ultrasonic treatment. The collagen solutions extracted under different ultrasonic powers had significant effects on the dynamic frequency sweep, but a steady shear test suggested that the collagen extracted at 150 W had the best viscosity. These results indicate that an ultrasonic power between 150 and 300 W can improve not only the extraction yield of natural collagen, but also the rheological properties of the collagen solution without compromising the triple helix structure.
Topics: Animals; Ultrasonics; Pepsin A; Fish Proteins; Collagen; Perciformes; Skin
PubMed: 38393055
DOI: 10.3390/md22020084