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Molecules (Basel, Switzerland) Mar 2021As nutrition and a health tonic for both medicine and food, the protein content of is more than 40%, making it an ideal source to produce antioxidant peptides. This...
As nutrition and a health tonic for both medicine and food, the protein content of is more than 40%, making it an ideal source to produce antioxidant peptides. This work evaluated the effects of six different proteases (pepsin, trypsin, papain, flavourzyme, neutral protease and alcalase) on the antioxidant activity of protein, and analyzed the relationship between the hydrolysis time, the degree of hydrolysis (DH) and the antioxidant activity of the enzymatic hydrolysates. The results showed that the antioxidant activity of protein was significantly improved and the optimal hydrolysis time was maintained between 3-4 h under the action of different proteases. Among them, the protein hydrolysate which was hydrolyzed by pepsin for 180 min had the strongest comprehensive antioxidant activity and was most suitable for the production of antioxidant peptides. At this time, the DH, the DPPH radical scavenging activity, the absorbance value of reducing power determination and the hydroxyl radical scavenging activity corresponding to the enzymatic hydrolysate were 13.32 ± 0.24%, 70.63 ± 1.53%, 0.376 ± 0.009 and 31.96 ± 0.78%, respectively. Correlation analysis showed that there was a significant positive correlation between the hydrolysis time, the DH and the antioxidant activity of the enzymatic hydrolysates, further indicating that the hydrolysates of protein had great antioxidant potential. The traditional anti-aging efficacy of is closely related to the scavenging of reactive oxygen species, and its hydrolysates have better antioxidant capacity, which also provides support for further development of its traditional anti-aging efficacy.
Topics: Antioxidants; Free Radical Scavengers; Hydrolysis; Hydroxyl Radical; Materia Medica; Pepsin A; Peptide Hydrolases; Protein Hydrolysates; Reactive Oxygen Species
PubMed: 33804057
DOI: 10.3390/molecules26061625 -
Scientific Reports Jun 2022Studies of microbiota reveal inter-relationships between the microbiomes of the gut and lungs. This relationship may influence the progression of lung disease,...
Studies of microbiota reveal inter-relationships between the microbiomes of the gut and lungs. This relationship may influence the progression of lung disease, particularly in patients with cystic fibrosis (CF), who often experience extraoesophageal reflux (EOR). Despite identifying this relationship, it is not well characterised. Our hypothesis is that the gastric and lung microbiomes in CF are related, with the potential for aerodigestive pathophysiology. We evaluated gastric and sputum bacterial communities by culture and 16S rRNA gene sequencing in 13 CF patients. Impacts of varying levels of bile acids, pepsin and pH on patient isolates of Pseudomonas aeruginosa (Pa) were evaluated. Clonally related strains of Pa and NTM were identified in gastric and sputum samples from patients with symptoms of EOR. Bacterial diversity was more pronounced in sputa compared to gastric juice. Gastric and lung bile and pepsin levels were associated with Pa biofilm formation. Analysis of the aerodigestive microbiomes of CF patients with negative sputa indicates that the gut can be a reservoir of Pa and NTM. This combined with the CF patient's symptoms of reflux and potential aspiration, highlights the possibility of communication between microorganisms of the gut and the lungs. This phenomenon merits further research.
Topics: Bacteria; Bile; Cystic Fibrosis; Gastric Juice; Gastroesophageal Reflux; Humans; Lung; Microbiota; Pepsin A; Pseudomonas aeruginosa; RNA, Ribosomal, 16S; Sputum
PubMed: 35773410
DOI: 10.1038/s41598-022-15375-4 -
PloS One 2020Mycobacterial culture remains the gold standard for the diagnosis of tuberculosis. However, an appropriate digestion and decontamination method (DDM) is essential for...
Papain-cetylpyridinium chloride and pepsin-cetylpyridinium chloride; two novel, highly sensitive, concentration, digestion and decontamination techniques for culturing mycobacteria from clinically suspected pulmonary tuberculosis cases.
Mycobacterial culture remains the gold standard for the diagnosis of tuberculosis. However, an appropriate digestion and decontamination method (DDM) is essential for the effective recovery of tubercle bacilli in culture. Therefore, the current study was designed to compare the performance of papain-cetylpyridinium chloride [papain-CPC] and pepsin-cetylpyridinium chloride [pepsin-CPC] DDMs against N-acetyl L-Cysteine-sodium hydroxide (NALC-NaOH) DDM for recovery of mycobacteria from clinically suspected pulmonary tuberculosis cases. To evaluate papain-CPC, pepsin-CPC and NALC-NaOH DDMs, sputum samples (N = 1381) were cultured on Löwenstein-Jensen medium and the results were compared. The papain-CPC DDM showed sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 93.27%, 71.7%, and 100%, respectively as compared to NALC-NaOH DDM. Similarly, pepsin-CPC DDM demonstrated sensitivity, specificity, positive predictive value and negative predictive value of 98.94%, 94.7%, 76.11%, and 99.81%, respectively. In summary, both papain-CPC and pepsin-CPC DDMs are highly sensitive and specific techniques for recovery of mycobacteria as compared to NALC-NaOH DDM. However, when the overall performances of all DDMs compared, papain-CPC DDM isolated increased number of mycobacterial isolates with comparatively higher numbers of colonies on LJ media than both pepsin-CPC and NALC-NaOH DDMs, indicating its potential to replace the NALC-NaOH DDM for recovery of mycobacteria from sputum samples.
Topics: Acetylcysteine; Bacteriological Techniques; Cetylpyridinium; Culture Media; Humans; Mycobacterium tuberculosis; Papain; Pepsin A; Sensitivity and Specificity; Specimen Handling; Sputum; Tuberculosis, Pulmonary
PubMed: 32750088
DOI: 10.1371/journal.pone.0236700 -
PloS One 2020Pepsin plays an important role in laryngopharyngeal reflux (LPR), a risk factor for the development of hypopharyngeal squamous cell carcinomas (HPSCC). However, the role...
Pepsin plays an important role in laryngopharyngeal reflux (LPR), a risk factor for the development of hypopharyngeal squamous cell carcinomas (HPSCC). However, the role of pepsin in HPSCC is not clear. We show by immunohistochemistry that pepsin positivity occurs in a significant proportion of human primary HPSCC specimens, and in many cases matched adjacent uninvolved epithelia are negative for pepsin. Pepsin positivity is associated with nodal involvement, suggesting that pepsin may have a role in metastasis. Treatment of FaDu cancer cells with pepsin increased cell proliferation, possibly by inducing G1/S transition. We also observed significant changes in expression of genes involved in NF-kappaB, TRAIL and Notch signaling. Our data suggest that pepsin plays an important role in HPSCC and that targeting pepsin could have potential therapeutic benefits.
Topics: Aged; Carcinoma, Squamous Cell; Cell Line, Tumor; Female; G1 Phase; Gene Expression Regulation, Neoplastic; Humans; Laryngeal Neoplasms; Male; Middle Aged; Neoplasm Metastasis; Neoplasm Proteins; Pepsin A; Pharyngeal Neoplasms; S Phase; Signal Transduction
PubMed: 31940393
DOI: 10.1371/journal.pone.0227408 -
European Archives of... Apr 2023The mechanism underlying malignant transformation of vocal fold leukoplakia (VFL) and the precise role of the expression of pepsin in VFL remain unclear. This study...
PURPOSE
The mechanism underlying malignant transformation of vocal fold leukoplakia (VFL) and the precise role of the expression of pepsin in VFL remain unclear. This study aimed to investigate the effects of acidified pepsin on VFL epithelial cell growth and migration, and also identify pertinent molecular mechanisms.
METHODS
Immunochemistry and Western blotting were performed to measure glucose transporter type 1 (GLUT1), monocarboxylate transporters 4 (MCT4), and Hexokinase-II (HK-II) expressions. Cell viability, cell cycle, apoptosis, and migration were investigated by CCK-8 assay, flow cytometry and Transwell chamber assay, respectively. Glycolysis-related contents were determined using the corresponding kits. Mitochondrial HK-II was photographed under a confocal microscope using Mito-Tracker Red.
RESULTS
It was found: the expression of pepsin and proportion of pepsin+ cells in VFL increased with the increased dysplasia grade; acidified pepsin enhanced cell growth and migration capabilities of VFL epithelial cells, reduced mitochondrial respiratory chain complex I activity and oxidative phosphorylation, and enhanced aerobic glycolysis and GLUT1 expression in VFL epithelial cells; along with the transfection of GLUT1 overexpression plasmid, 18FFDG uptake, lactate secretion and growth and migration capabilities of VFL epithelial cell were increased; this effect was partially blocked by the glycolysis inhibitor 2-deoxy-glucose; acidified pepsin increased the expression of HK-II and enhanced its distribution in mitochondria of VFL epithelial cells.
CONCLUSION
It was concluded that acidified pepsin enhances VFL epithelial cell growth and migration abilities by reducing mitochondrial respiratory complex I activity and promoting metabolic reprogramming from oxidative phosphorylation to aerobic glycolysis.
Topics: Humans; Pepsin A; Vocal Cords; Glucose Transporter Type 1; Glycolysis; Epithelial Cells; Leukoplakia
PubMed: 36380093
DOI: 10.1007/s00405-022-07729-5 -
Communications Biology Aug 2021Protein-based targeting reagents, such as antibodies and non-antibody scaffold proteins, are rapidly inactivated in the upper gastrointestinal (GI) tract. Hydrochloric...
Protein-based targeting reagents, such as antibodies and non-antibody scaffold proteins, are rapidly inactivated in the upper gastrointestinal (GI) tract. Hydrochloric acid in gastric juice denatures proteins and activates pepsin, concentrations of which reach 1 mg/mL in the mammalian stomach. Two stable scaffold proteins (nanobody and nanofitin), previously developed to be protease-resistant, were completely digested in less than 10 min at 100-fold lower concentration of pepsin than found in the stomach. Here we present gastrobodies, a protein scaffold derived from Kunitz soybean trypsin inhibitor (SBTI). SBTI is highly resistant to the challenges of the upper GI tract, including digestive proteases, pH 2 and bile acids. Computational prediction of SBTI's evolvability identified two nearby loops for randomization, to create a potential recognition surface which was experimentally validated by alanine scanning. We established display of SBTI on full-length pIII of M13 phage. Phage selection of gastrobody libraries against the glucosyltransferase domain of Clostridium difficile toxin B (GTD) identified hits with nanomolar affinity and enzyme inhibitory activity. Anti-GTD binders retained high stability to acid, digestive proteases and heat. Gastrobodies show resilience to exceptionally harsh conditions, which should provide a foundation for targeting and modulating function within the GI tract.
Topics: Animals; Antibodies; Biomimetic Materials; Chickens; Clostridioides difficile; Female; Hydrochloric Acid; Mice; Mice, Inbred BALB C; Pepsin A; Trypsin Inhibitor, Kunitz Soybean
PubMed: 34381153
DOI: 10.1038/s42003-021-02487-2 -
Pediatric Pulmonology Aug 2021To assess the association between commonly obtained endoscopic and serologic data and bronchoalveolar lavage pepsin assay (BAL) results in children with chronic cough.
OBJECTIVE
To assess the association between commonly obtained endoscopic and serologic data and bronchoalveolar lavage pepsin assay (BAL) results in children with chronic cough.
STUDY DESIGN
We performed a retrospective chart review of 72 children with a BAL pepsin obtained through our Aerodigestive Center over an 18-month period. BAL outcomes include evidence of viral, bacterial, or fungal infection, presence of lipid-laden macrophages, and cytology (eosinophils, neutrophils, and lymphocytes). Gastrointestinal outcomes include esophagogastroduodenoscopy (EGD) and pH impedance probe findings. Other characteristics include serum eosinophils, neutrophils, and lymphocytes; spirometry; FeNO; and IgE.
RESULTS
Seventy-two patients underwent BAL pepsin testing. Median age was 4.9 years, 30.6% had severe persistent asthma, and 59.2% were on reflux medication. There was an association between positive BAL pepsin assay and positive viral panel (p = .002) or fungal culture (p = .027). No significant association found between positive BAL bacterial culture; BAL cytology; the presence of BAL lipid-laden macrophages; IgE; spirometry; FeNO; CBC neutrophil, eosinophil, or lymphocytes; pH impedance testing parameters; or EGD pathology.
CONCLUSIONS
BAL pepsin is associated with a positive BAL viral PCR or fungal culture. Lack of correlation between pepsin-positivity and pH-impedance parameters or EGD pathology suggests microaspiration may be due to an acute event (such as a respiratory infection) rather than chronic gastroesophageal reflux disease. This may be especially true in the presence of a positive viral panel or fungal culture when a BAL pepsin is obtained.
Topics: Bronchoalveolar Lavage; Bronchoalveolar Lavage Fluid; Child; Child, Preschool; Cough; Humans; Mycoses; Pepsin A; Respiratory Tract Infections; Retrospective Studies
PubMed: 33930245
DOI: 10.1002/ppul.25450 -
The Laryngoscope Feb 2021To assess the impact of diet on the saliva pepsin concentration of patients with laryngopharyngeal reflux (LPR).
OBJECTIVES/HYPOTHESIS
To assess the impact of diet on the saliva pepsin concentration of patients with laryngopharyngeal reflux (LPR).
STUDY DESIGN
Non-controlled Prospective Study.
METHODS
Patients with positive LPR regarding hypopharyngeal-esophageal impedance-pH monitoring (HEMII-pH) were enrolled from three European Hospitals. Patients collected three saliva samples, respectively, in the morning (fasting), and 1 to 2 hour after lunch and dinner. Patients carefully detailed foods and beverages consumed during meals and before the pepsin samples. The 3-month treatment was based on the association of diet, proton pump inhibitors, alginate, or magaldrate regarding the HEMII-pH characteristics. Reflux Symptom Score (RSS) and Reflux Sign Assessment (RSA) were used for assessing the pre- to posttreatment clinical evolution. The Refluxogenic Diet Score and the Refluxogenic Score of a Dish (RESDI) were used to assess the refluxogenic potential of foods and beverages. The relationship between saliva pepsin concentration, HEMII-pH, RESDI, RSS, and RSA was investigated through multiple linear regression.
RESULTS
Forty-two patients were included. The saliva pepsin concentration of the 24-hour period of testing was significantly associated with foods and beverages consumed during the testing period and the evening dinner (r = 0.973, P < .001). RSS and RSA significantly improved throughout treatment. The level of saliva pepsin in the morning was a negative predictive factor of the therapeutic response regarding RSA and RSS (P < .036).
CONCLUSIONS
Foods and beverages may significantly impact the saliva pepsin concentration of patients with LPR. Patients with high-level saliva pepsin in the morning had lower therapeutic response compared with those with low-level saliva pepsin.
LEVEL OF EVIDENCE
4 Laryngoscope, 131:350-359, 2021.
Topics: Adult; Aged; Diet; Diet Surveys; Electric Impedance; Esophageal pH Monitoring; Female; Humans; Laryngopharyngeal Reflux; Male; Meals; Middle Aged; Pepsin A; Prospective Studies; Proton Pump Inhibitors; Saliva; Severity of Illness Index; Young Adult
PubMed: 32510588
DOI: 10.1002/lary.28756 -
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 -
Ultrasonics Sonochemistry May 2023Broiler chicken tracheas are a co-product from chicken slaughterhouses which are normally turned into low value animal feed despite their high levels of collagen....
Broiler chicken tracheas are a co-product from chicken slaughterhouses which are normally turned into low value animal feed despite their high levels of collagen. Typical collagen extraction by acid and/or pepsin usually results in relatively low yield. Ultrasound-assisted extraction (UAE) could be a means to improve collagen yield. The objectives of this study were to investigate the effects of ultrasonic parameters on the yield and biochemical properties of trachea collagen (TC). Conventional extraction using acetic acid and pepsin for 48 h resulted in acid-soluble (AS) and pepsin-soluble (PS) collagen with a yield of 0.65% and 3.10%, respectively. When an ultrasound with an intensity of 17.46 W·cm was applied for 20 min, followed by acid extraction for 42 h (U-AS), the collagen yield increased to 1.58%. A yield of 6.28% was obtained when the ultrasound treatment was followed by pepsin for 36 h (U-PS). PS and U-PS contained collagen of 82.84% and 85.70%, respectively. Scanning electron microscopy images revealed that the ultrasound did not affect the collagen microstructure. All collagen samples showed an obvious triple helix structure as measured by circular dichroism spectroscopy. Fourier transform infrared spectroscopy indicated that the ultrasound did not disturb the secondary structure of the protein in which approximately 30% of the α-helix content was a major structure for all collagen samples. Micro-differential scanning calorimetry demonstrated that the denaturation temperature of collagen in the presence of deionized water was higher than collagen solubilized in 0.5 M acetic acid, regardless of the extraction method. All collagen comprised of α and α-units with molecular weights of approximately 135 and 116 kDa, respectively, corresponding to the type I characteristic. PS and U-PS collagen possessed higher imino acids than their AS and U-AS counterparts. Based on LC-MS/MS peptide mapping, PS and U-PS collagen showed a high similarity to type I collagen. These results suggest that chicken tracheas are an alternative source of type I collagen. UAE is a promising technique that could increase collagen yield without damaging its structure.
Topics: Animals; Collagen Type I; Chickens; Trachea; Pepsin A; Chromatography, Liquid; Tandem Mass Spectrometry; Collagen; Acetic Acid
PubMed: 36944278
DOI: 10.1016/j.ultsonch.2023.106372