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Pediatric Gastroenterology, Hepatology... Jan 2024This study aimed to investigate the presence of autoantigens in the gastric juices of children.
PURPOSE
This study aimed to investigate the presence of autoantigens in the gastric juices of children.
METHODS
Gastric juice and serum samples were obtained from 53 children <15 years of age who underwent gastric endoscopy. Among these, 8, 22, and 23 participants were in the age groups 0-5, 6-10, and 11-15 years, respectively. These samples were analyzed using two-dimensional electrophoresis (2-DE), immunoblot analysis, and matrix-assisted laser desorption ionization-time of-flight mass spectrometry. Furthermore, we reviewed the histopathological findings and urease test results and compared them with the results of 2-DE and immunoblot analysis.
RESULTS
There were no statistically significant differences in urease test positivity, grades of chronic gastritis, active gastritis, or infiltration of the antrum and body among the three age groups. Three distinct patterns of gastric juice were observed on 2-DE. Pattern I was the most common, and pattern III was not observed below the age of 5 years. Histopathological findings were significantly different among active gastritis (=0.037) and infiltration (=0.060) in the gastric body. The immunoblots showed large spots at an approximate pH of 3-4 and molecular weights of 31-45 kDa. These distinct, large positive spots were identified as gastric lipase and pepsin A and C.
CONCLUSION
Three enzymes, which are normally secreted under acidic conditions were identified as autoantigens. Further investigation of the pathophysiology and function of autoantigens in the stomach is required.
PubMed: 38249638
DOI: 10.5223/pghn.2024.27.1.15 -
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 -
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 -
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 -
Environmental Pollution (Barking, Essex... Oct 2023Human ingestion of microplastics (MPs) is common and inevitable due to the widespread contamination of food items, but implications on the gastric digestion of food...
Human ingestion of microplastics (MPs) is common and inevitable due to the widespread contamination of food items, but implications on the gastric digestion of food proteins are still unknown. In this study, the interactions between pepsin and polystyrene (PS) MPs were evaluated by investigating enzyme activity and conformation in a simulated human gastric environment in the presence or absence of PS MPs. The impact on food digestion was also assessed by monitoring the kinetics of protein hydrolysis through static in vitro gastric digestion of cow's milk contaminated with PS. The binding of pepsin to PS showed that the surface chemistry of MPs dictates binding affinity. The key contributor to pepsin adsorption seems to be π-π interactions between the aromatic residues and the PS phenyl rings. During quick exposure (10 min) of pepsin to increasing concentrations (222, 2219, 22188 particles/mL) of 10 μm PS (PS10) and 100 μm PS (PS100), total enzymatic activities were not affected remarkably. However, upon prolonged exposure at 1 and 2 h, preferential binding of pepsin to the small, low zeta-potential PS caused structural changes in the protein which led to a significant reduction of its activity. Digestion of cow's milk mixed with PS10 resulted in transient accumulation of larger peptides (10-35 kDa) and reduced bioavailability of short peptides (2-9 kDa) in the gastric phase. This, however, was only observed at extremely high PS10 concentration (0.3 mg/mL or 5.46E+05 particles/mL). The digestion of milk peptides, bound preferentially over pepsin within the hard corona on the PS10 surface, was delayed up to 15 min in comparison to bulk protein digestion. Intact caseins, otherwise rapidly digested, remained bound to PS10 in the hard corona for up to 15 min. This work presents valuable insights regarding the interaction of MPs, food proteins, and pepsin, and their dynamics during gastric digestion.
Topics: Humans; Milk Proteins; Pepsin A; Microplastics; Polystyrenes; Plastics; Peptides; Caseins; Allergens; Digestion
PubMed: 37516294
DOI: 10.1016/j.envpol.2023.122282 -
Scientific Reports Dec 2023To analyze the predictive value of salivary pepsin for treatment outcomes in laryngopharyngeal reflux (LPR) using multivariate analysis that includes various associated...
To analyze the predictive value of salivary pepsin for treatment outcomes in laryngopharyngeal reflux (LPR) using multivariate analysis that includes various associated factors. This prospective cohort study was conducted between August 2020 and August 2022. Patients with LPR who had symptoms lasting more than 1 month and a reflux symptom index (RSI) of 14 or higher were enrolled. The participants received a 2-month regimen of proton pump inhibitors (PPIs) treatment and lifestyle modification. Salivary pepsin was checked using fasting saliva before treatment. Salivary pepsin was detected more frequently in the good treatment response group (61.1%), compared to 14.3% in the poor response group. Similarly, patients with higher compliance to lifestyle modifications (> 90%) had a higher chance of a good response (91.7%) compared to those with lower compliance, who had a 53.8% chance of a good response. Other clinical factors have no significant association with treatment response. In multivariate analysis, both pretreatment salivary pepsin and higher compliance with lifestyle modification were found to be independent factors for treatment response (OR 14.457, CI 1.075 ~ 194.37 for both). This study found that positive salivary pepsin and strict lifestyle modification are independent predictors of treatment outcomes in LPR.
Topics: Humans; Pepsin A; Prospective Studies; Laryngopharyngeal Reflux; Saliva; Multivariate Analysis
PubMed: 38129481
DOI: 10.1038/s41598-023-50014-6 -
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 -
PloS One 2023Today, breast cancer and infectious diseases are very worrying that led to a widespread effort by researchers to discover natural remedies with no side effects to fight...
Today, breast cancer and infectious diseases are very worrying that led to a widespread effort by researchers to discover natural remedies with no side effects to fight them. In the present study, we isolated camel milk protein fractions, casein and whey proteins, and hydrolyzed them using pepsin, trypsin, and both enzymes. Screening of peptides with anti-breast cancer and antibacterial activity against pathogens was performed. Peptides derived from whey protein fraction with the use of both enzymes showed very good activity against MCF-7 breast cancer with cell viability of 7.13%. The separate use of trypsin and pepsin to digest whey protein fraction yielded peptides with high antibacterial activity against S. aureus (inhibition zone of 4.17 ± 0.30 and 4.23 ± 0.32 cm, respectively) and E. coli (inhibition zone of 4.03 ± 0.15 and 4.03 ± 0.05 cm, respectively). Notably, in order to identify the effective peptides in camel milk, its protein sequences were retrieved and enzymatically digested in silico. Peptides that showed both anticancer and antibacterial properties and the highest stability in intestinal conditions were selected for the next step. Molecular interaction analysis was performed on specific receptors associated with breast cancer and/or antibacterial activity using molecular docking. The results showed that P3 (WNHIKRYF) and P5 (WSVGH) peptides had low binding energy and inhibition constant so that they specifically occupied active sites of protein targets. Our results introduced two peptide-drug candidates and new natural food additive that can be delivered to further animal and clinical trials.
Topics: Animals; Camelus; Protein Hydrolysates; Escherichia coli; Molecular Docking Simulation; Pepsin A; Staphylococcus aureus; Trypsin; Whey Proteins; Neoplasms; Peptides; Anti-Bacterial Agents
PubMed: 37437001
DOI: 10.1371/journal.pone.0288260 -
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 -
Biomedical Engineering Online Jul 2023Tube misplacement into the tracheobronchial tract is associated with pneumothorax in 0.5% of cases. NGT verification only detects the position of the tube at the end of...
Preclinical trial of the effectiveness of a safety nasogastric tube to detect the tube position based on tidal volume and pepsin assay results in the gastrointestinal tract of Macaca fascicularis.
BACKGROUND
Tube misplacement into the tracheobronchial tract is associated with pneumothorax in 0.5% of cases. NGT verification only detects the position of the tube at the end of the procedure. Therefore, a safe nasogastric tube (SNGT) was created to detect the NGT position in real time in a simple and inexpensive way. This study aimed to prove the effectiveness of the SNGT prototype in Macaca fascicularis.
RESULT
An SNGT producing 50% of the TV had 100% sensitivity and specificity in detecting the position of the tube at 100% of the TV, with a sensitivity of 100% and a specificity of 87.5%. There was a significant difference between the movement of the SNGT 50% TV and SNGT 100% TV airbags (p ≤ 0.05). However, there was no significant difference between the accuracy of placement of the 50% TV SNGT, 100% TV SNGT, and conventional NGT (p > 0.05). The pepsin enzyme had better sensitivity (100%) than pH paper (91.66%) in detecting the end-of-procedure tube position. This research has the potential to advance into human clinical trials.
CONCLUSION
SNGTs are highly effective in detecting the NGT position inside the respiratory and digestive tracts to prevent misplacement.
Topics: Animals; Gastrointestinal Tract; Intubation, Gastrointestinal; Macaca fascicularis; Pepsin A; Tidal Volume; Clinical Trials as Topic
PubMed: 37443035
DOI: 10.1186/s12938-023-01128-5