Preparation of Corn Peptides with Anti-Adhesive Activity and Its Functionality to Alleviate Gastric Injury Induced by Helicobacter pylori Infection In Vivo

Plant-derived extracts or compounds for Helicobacter-associated gastritis: a systematic review of their anti-Helicobacter activity and anti-inflammatory effect in animal experiments

BACKGROUND

Helicobacter infection, which is the leading cause of gastritis and stomach cancer, has become common worldwide. Almost all Helicobacter-infected patients have chronic active gastritis, also known as Helicobacter-associated gastritis (HAG). However, the eradication rate of Helicobacter is decreasing due to the poor efficacy of current medications, which causes infection to recur, inflammation to persist, and stomach cancer to develop. Natural components have robust antibacterial activity and anti-inflammatory capacity, as confirmed by many studies of alternative natural medicines.

PURPOSE

This article aimed to conduct a comprehensive search and meta-analysis to evaluate the efficacy of anti-Helicobacter and anti-inflammatory activities of plant-derived extracts or compounds that can treat HAG in animal experiments. We intended to provide detailed preclinical-research foundation including plant and compound information, as well as the mechanisms by which these plant-derived substances inhibit the progression of Helicobacter infection, gastritis and neoplasms for future study.

METHODS

The systematic review is aligned with the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, and the protocol was registered in PROSPERO (CRD42024527889). An extensive search was performed across multiple databases, including PubMed, Scopus, Web of Science, Embase, China National Knowledge Infrastructure (CNKI), the Chinese Scientific Journal database (VIP), the Wanfang database, and the China biomedical literature service system (SinoMed), up until November 2023. Meta-analysis on Review Manager software (RevMan 5.4) estimating anti-Helicobacter and anti-inflammatory activity was performed. We used the Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) risk of bias tool to evaluate the risk of bias of each study included.

RESULTS

Our study encompassed 61 researches, comprised 36 extracts and 37 compounds improving HAG by inhibiting Helicobacter infection, the inflammatory response, oxidative stress, and regulating apoptosis and proliferation. Sixteen families especially Asteraceae, Fabaceae and Rosaceae and nine classes including Terpenoids, Alkaloids, Phenols, and Flavonoids may be promising directions for valuable new drugs. The Meta-analyse demonstrated the plant-base substance treatments possess significant anti-Helicobacter and anti-inflammation activity comparing to control groups. The included plants and compounds confirmed that signaling pathways NF-κB, JAK2/STAT3, MAPK, TLR4/MyD88, PI3K/AKT, NLRP3/Caspase-1 and NRF2/HO-1 play a key role in the progression of HAG.

CONCLUSION

Plant-derived extracts or compounds actively improve HAG by modulating relevant mechanisms and signaling pathways, particularly through the anti-Helicobacter and inflammatory regulation ways. Further researches to apply these treatments in humans are needed, which will provide direction for the future development of therapeutic drugs to increase eradication rate and alleviate gastritis.

Transcriptomic Insights Into Electroacupuncture Using Different Acupoint Combinations to Repair Mucosal Inflammatory Injury Induced in a Rat Model of Gastric Ulcer

Background

Electroacupuncture (EA) is a promising treatment for gastrointestinal disorders, yet the efficacy of different acupoint combinations remains mechanistically undefined. We evaluated the therapeutic effects of different acupoint combinations on mucosal inflammatory injury induced in a rat model of gastric ulcer (GU) and dissected its molecular mechanisms through transcriptomic profiling.

Methods

A GU rat model was established using hypothermic restrained water immersion stress. EA therapy was administered to the He-Mu (ST36-CV12), Shu-Mu (BL21-CV12), and Yuan-Luo (ST42- ST40) acupoint combinations for 5 days. EA therapeutic effects were evaluated by coat score, fecal moisture percentage, pain threshold, body mass, organ index, histopathological changes, serum level of oxidative stress, and inflammatory cytokine levels in gastric tissue. A transcriptome analysis identified the related differentially expressed genes (DEGs) and central signaling pathway. Real-time quantitative PCR and Western blot were performed to verify the mRNA and protein expression levels of the main genes in the central pathway.

Results

EA using different acupoint combinations differentially alleviated gastric mucosal injury in GU rats, with the He-Mu group exhibiting superior tissue damage alleviation, as well as inflammation and oxidative stress reductions. A Venn diagram transcriptome analysis revealed a shared central pathway among the three groups, corresponding to focal adhesion. Quantitative validation confirmed that the mRNA, protein, and phosphorylated protein expression of FAK, VCL, and EGFR-the core signal transduction factors of the focal adhesion pathway activated in gastric tissue after EA treatment-were upregulated, consistent with their therapeutic efficacy.

Conclusion

Our results demonstrated that the He-Mu acupoint combination exhibited superior therapeutic efficacy among the three acupoint combinations. EA using different acupoint combinations improved gastric mucosal injury to varying degrees, and was related to the focal adhesion pathway. The FAK, VCL, and EGFR are promising targets, and further studies are needed to elucidate their functional consequences in GU.

Biologically Active Peptides from Corn Gluten Meal Improve Microbiota Disorders Caused by Helicobacter pylori Infection in Mice

This study investigated the potential effects of corn protein activity peptides (CPAPs) on inflammation response levels and gastrointestinal microbiota in Helicobacter pylori (H. pylori) infection mice. CPAPs significantly up-regulated the mRNA expression of the anti-inflammatory factor IL-10 and down-regulated the mRNA expression of the pro-inflammatory factors TGF-β, TLR4, MyD88, and NF-κB, indicating that CPAPs may antagonize H. pylori-induced inflammatory responses by inhibiting NF-κB signaling pathways. Through the intervention of CPAPs, H. pylori colonization in the stomach was significantly reduced. Additionally, the structural composition of the gastrointestinal microbiota improved, with an increase in abundance and diversity. These changes positively regulate gastrointestinal microbiota disorders in mice. In addition, the PICRUST function prediction of intestinal microbiota revealed that CPAPs may prevent or reduce metabolic disorders brought about by H. pylori, which improve biometabolic pathways by modulating intestinal microbiota composition. In conclusion, these findings suggest that CPAPs may prevent or mitigate metabolic disorders induced by H. pylori, offering theoretical support for the development of corn-protein-based functional foods.

Serum levels of oxidative stress, IL-8, and pepsinogen I/II ratio in Helicobacter pylori and gastric cancer patients: potential diagnostic biomarkers

BACKGROUND AND AIM

Helicobacter pylori (H.pylori), a gram-negative bacterial pathogen associated with an increased risk of gastric cancer. This study investigates potential factors in the incidence of gastric cancer in patients with H.pylori, including oxidative stress, inflammatory biomarkers, serum pepsinogens (PG) of I and II, and PG-I/PG-II ratio.

METHODS

The study comprised individuals with Helicobacter pylori (H.pylori) infection, gastric cancer patients, and healthy individuals. Biochemical parameters such as FBS (fasting blood sugar), lipid profile, and liver and kidney functional factors were evaluated using colorimetric techniques. Oxidative markers such as total oxidant status (TOS) and malondialdehyde (MDA) were quantified through colorimetric methods. IL-8, PG-II, and PG-II levels were also determined using the ELISA technique.

RESULTS

Individuals with H. pylori infection exhibited elevated levels of IL-8 (940.5 ± 249.7 vs. 603.4 ± 89.1 pg/ml, P < 0.0001) and oxidative species (5.47 ± 0.7 vs. 1.64 ± 0.7 nM, P < 0.05) compared to gastric cancer patients, who, despite having lower levels of IL-8 and oxidative species, showed higher levels of MDA. H.pylori patients exhibited significantly higher levels of PG-I (7.28 ± 2.1 vs. 2.61 ± 1.4 ng/ml, P < 0.001), PG-II (3.21 ± 1 vs. 2.6 ± 0.6 ng/ml, P < 0.001), and the PG-I/PG-II ratio (2.27 ± 1.2 vs. 1 ± 0.4, P < 0.001) compared to gastric cancer patients. The findings were substantiated using various data analysis platforms such as Gene Expression Profiling Interactive Analysis (GEPIA), UALCAN (The University of ALabama at Birmingham CANcer data analysis), cBioPortal, and TIMER (Tumor IMmune Estimation Resource). These parameters could serve as potential diagnostic biomarkers for screening and therapeutic interventions based on the cut-off values derived from ROC (receiver operating characteristic) curves for IL-8, PGI, PGII, and PGI/PGII across the three groups.

CONCLUSIONS

IL-8, PGI, PGII, and PGI/PGII parameters could serve as potential diagnostic markers for the screening and treatment of gastric conditions.

Natural anti-adhesive components against pathogenic bacterial adhesion and infection in gastrointestinal tract: case studies of Helicobacter pylori, Salmonella enterica, Clostridium difficile, and diarrheagenic Escherichia coli

Antimicrobial resistance (AMR) poses a global public health concern. Recognizing the critical role of bacterial adhesion in pathogenesis of infection, anti-adhesive therapy emerges as a promising approach to impede initial bacterial attachment, thus preventing pathogenic colonization and infection. Natural anti-adhesive agents derived from food sources are generally safe and have the potential to inhibit the emergence of resistant bacteria. This comprehensive review explored diverse natural dietary components exhibiting anti-adhesive activities against several model enteric pathogens, including Helicobacter pylori, Salmonella enterica, Clostridium difficile, and three key diarrheagenic Escherichia coli (i.e., enterotoxigenic E. coli, enteropathogenic E. coli, and enterohemorrhagic E. coli). Investigating various anti-adhesive products will advance our understanding of current research of the field and inspire further development of these agents as potential nutraceuticals or adjuvants to improve the efficacy of conventional antibiotics.

Four novel anti-adhesive activity peptides against Helicobacter pylori derived from rice bran protein: release, identification and anti-adhesive mechanisms elucidation

H. pylori is a highly pathogenic and prevalent pathogen that is a class I carcinogen. More than 50% of the world's population is infected with H. pylori. An anti-adhesive strategy is an effective way to antagonize H. pylori infection, which does not cause H. pylori resistance and is safer compared to antibiotic therapy. In the present study, to obtain rice bran protein-derived anti-adhesive activity peptides against H. pylori, an efficient enzymatic hydrolysis system was established, and it was found that rice bran protein hydrolysate prepared under specific conditions possessed anti-adhesive activity against H. pylori. The anti-adhesive activity of rice bran protein hydrolysate (RPH) was 43.74 ± 1.12% (4 mg mL-1), and gastric digestion (RPHA) had no significant effect on its activity. Hydrophobic amino acids and aromatic amino acids were important for its anti-adhesive activity. Further, 284 peptide sequences with potential anti-adhesive activity were isolated and identified from RPHA. Combined with molecular docking results, four novel anti-adhesive activity peptides were finally screened, namely LS5 (LSFRL), SN8 (SNTPGMVY), VV7 (VVNFGNL) and PV9 (PVLWGVPKG). Among them, PV9 showed the highest anti-adhesive activity of 59.64 ± 2.00% (4 mg mL-1). These four peptides could bind H. pylori adhesins BabA and SabA, occupying the binding sites of cell receptors and acting as anti-adhesion agents. In conclusion, four rice bran protein-derived anti-adhesive activity peptides against H. pylori can be used for the development of novel functional foods antagonizing H. pylori infection.

Indole-3-Lactic Acid Derived from Lacticaseibacillus paracasei Inhibits Helicobacter pylori Infection via Destruction of Bacteria Cells, Protection of Gastric Mucosa Epithelial Cells, and Alleviation of Inflammation

Indole-3-lactic acid (ILA) has exhibited antimicrobial properties. However, its role in inhibiting Helicobacter pylori infection remains elusive. This study investigated the inhibitory effect of ILA produced by Lacticaseibacillus paracasei on H. pylori, which was further confirmed by cell and animal experiments. 5 mg/mL ILA was sufficient to directly inhibit the growth of H. pylori in vitro, with a urease inhibitory activity reaching 60.94 ± 1.03%, and the cell morphology and structure were destroyed. ILA inhibited 56.5% adhesion of H. pylori to GES-1 and significantly reduced the number of apoptotic cells. Furthermore, ILA suppresses H. pylori colonization by approximately 38% to 63%, reduced inflammation and oxidative stress in H. pylori-infected mice, and enhanced the enrichment and variety of gut microbiota, notably fostering the growth of beneficial bacteria such as Lactobacillus and Bifidobacterium strains. The results support that ILA derived from Lactobacillus can be applicated as a novel prebiotic in anti-H. pylori functional foods.

Purification, identification and molecular docking of dual-functional peptides derived from corn protein hydrolysates with antioxidant and antiadhesive activity against Helicobacter pylori

BACKGROUND

More than 50% of the world's population is infected with Helicobacter pylori, which is classified as a group I carcinogen by the World Health Organization (WHO).

RESULTS

Corn protein dual-functional peptides were identified and functionally analyzed in vitro and in silico. Two novel dual-functional peptides were identified as Cys-Gln-Asp-Val-Pro-Leu-Leu (CQDVPLL, CQ7) and Thr-Ile-Phe-Pro-Gln-Cys (TIFPQC, TI6) using nanoscale liquid chromatography coupled to tandem mass spectrometry (nano-LC-MS/MS). The antiadhesive effects against H. pylori of CQ7 and TI6 were 45.17 ± 2.41% and 48.62 ± 1.84% at 4 mg mL-1 , respectively. In silico prediction showed that CQ7 and TI6 had good physicochemical properties. Molecular docking demonstrated that CQ7 and TI6 could bind to the adhesins BabA and SabA by hydrophobic interactions and hydrogen bonds, preventing H. pylori infection. Moreover, CQ7 showed strong antioxidant activity due to its unique amino acid composition.

CONCLUSION

The present study demonstrated that the identified peptides, CQ7 and TI6, possess antioxidant and antiadhesive effects, preventing H. pylori infection and alleviating oxidative injury to the gastric mucosa. © 2023 Society of Chemical Industry.

Identification of Corn Peptides with Alcohol Dehydrogenase Activating Activity Absorbed by Caco-2 Cell Monolayers

Alcohol dehydrogenase (ADH) plays a pivotal role in constraining alcohol metabolism. Assessing the ADH-activating activity in vitro can provide insight into the capacity to accelerate ethanol metabolism in vivo. In this study, ADH-activating peptides were prepared from corn protein meal (CGM) using enzymatic hydrolysis, and these peptides were subsequently identified following simulated gastrointestinal digestion and their absorption through the Caco-2 cell monolayer membrane. The current investigation revealed that corn protein hydrolysate hydrolyzed using alcalase exhibited the highest ADH activation capability, maintaining an ADH activation rate of 52.93 ± 2.07% following simulated gastrointestinal digestion in vitro. After absorption through the Caco-2 cell monolayer membrane, ADH-activating peptides were identified. Among them, SSNCQPF, TGCPVLQ, and QPQQPW were validated to possess strong ADH activation activity, with EC50 values of 1.35 ± 0.22 mM, 2.26 ± 0.16 mM, and 2.73 ± 0.13 mM, respectively. Molecular Docking revealed that the activation of ADH occurred via the formation of a stable complex between the peptide and the active center of ADH by hydrogen bonds and hydrophobic interactions. The results of this study also suggest that corn protein hydrolysate could be a novel functional dietary element that helps protects the liver from damage caused by alcohol and aids in alcohol metabolism.