Probing the expression and adhesion of glycans involved in Helicobacter pylori infection.

Helicobacter pylori infects approximately half the human population and has an unusual infective niche of the human stomach. Helicobacter pylori is a major cause of gastritis and has been classified as a group 1 carcinogen by the WHO. Treatment involves triple or quadruple antibiotic therapy, but antibiotic resistance is becoming increasingly prevalent. Helicobacter pylori expresses certain blood group related antigens (Lewis system) as a part of its lipopolysaccharide (LPS), which is thought to assist in immune evasion. Additionally, H. pylori LPS participates in adhesion to host cells alongside several adhesion proteins. This study profiled the carbohydrates of H. pylori reference strains (SS1 and 26695) using monoclonal antibodies (mAbs) and lectins, identifying interactions between two carbohydrate-targeting mAbs and multiple lectins. Atomic force microscopy (AFM) scans were used to probe lectin and antibody interactions with the bacterial surfaces. The selected mAb and lectins displayed an increased adhesive force over the surface of the curved H. pylori rods. Furthermore, this study demonstrates the ability of anti-carbohydrate antibodies to reduce the adhesion of H. pylori 26695 to human gastric adenocarcinoma cells via AFM. Targeting bacterial carbohydrates to disrupt crucial adhesion and immune evasion mechanisms represents a promising strategy for combating H. pylori infection.

A reconstructed genome-scale metabolic model of Helicobacter pylori for predicting putative drug targets in clarithromycin and rifampicin resistance conditions.

BACKGROUND: Helicobacter pylori is considered a true human pathogen for which rising drug resistance constitutes a drastic concern globally. The present study aimed to reconstruct a genome-scale metabolic model (GSMM) to decipher the metabolic capability of H. pylori strains in response to clarithromycin and rifampicin along with identification of novel drug targets. MATERIALS AND METHODS: The iIT341 model of H. pylori was updated based on genome annotation data, and biochemical knowledge from literature and databases. Context-specific models were generated by integrating the transcriptomic data of clarithromycin and rifampicin resistance into the model. Flux balance analysis was employed for identifying essential genes in each strain, which were further prioritized upon being nonhomologs to humans, virulence factor analysis, druggability, and broad-spectrum analysis. Additionally, metabolic differences between sensitive and resistant strains were also investigated based on flux variability analysis and pathway enrichment analysis of transcriptomic data. RESULTS: The reconstructed GSMM was named as HpM485 model. Pathway enrichment and flux variability analyses demonstrated reduced activity in the ribosomal pathway in both clarithromycin- and rifampicin-resistant strains. Also, a significant decrease was detected in the activity of metabolic pathways of clarithromycin-resistant strain. Moreover, 23 and 16 essential genes were exclusively detected in clarithromycin- and rifampicin-resistant strains, respectively. Based on prioritization analysis, cyclopropane fatty acid synthase and phosphoenolpyruvate synthase were identified as putative drug targets in clarithromycin- and rifampicin-resistant strains, respectively. CONCLUSIONS: We present a robust and reliable metabolic model of H. pylori. This model can predict novel drug targets to combat drug resistance and explore the metabolic capability of H. pylori in various conditions.

Proportion of cancer cases and deaths attributable to potentially modifiable risk factors in Peru.

BACKGROUND: Limited evidence exists on the population attributable fraction (PAF) of cancer cases and deaths in Latin America. In Peru several studies have been published regarding the PAF of various risk factors and their associated diseases. The objective of this study was to estimate the fraction of cancer cases and deaths attributable to potentially modifiable risk factors in Peru in 2018, before the COVID-19 pandemic in the population of 15 years old and older. METHODS: An ecological study was conducted using the prevalence of exposure of the Peruvian population to modifiable risk factors for cancer, the relative risk associated with each factor, and the number of cancer cases and deaths in 2018 as inputs. We used the Parkin formula with a Montecarlo statistical simulation model to calculate the PAF and confidence intervals. The number of new cancer cases and deaths attributed to each risk factor was determined by multiplying the number of cases and deaths in each gender by the PAF of each risk factor. FINDINGS: In Peru, 38.5% of new cases (34.5% in men and 42% in women) and 43.4% of cancer-related deaths (43.4% in men and 43.4% in women) were attributable to modifiable risk factors. The number of cancers attributable was 25,308 (10,439 in men and 14,869 in women) and the number of deaths attributable to cancer was 14,839 (6,953 in men and 7,886 in women). The predominant modifiable risk factors contributing to the highest number of cases and deaths were HPV infection (4,563 cases, 2,409 deaths), current tobacco use (3,348 cases, 2,180 deaths), and helicobacter pylori infection (2,677 cases, 1,873 deaths). Among the risk factors, oncogenic infections constituted the group with the highest PAF (16.6% for cases, 19.2% for deaths) followed by other unhealthy lifestyle factors (14.2% for cases, 16.7% for deaths), tobacco (7.2% for cases, 7.2% for deaths) and ultraviolet radiation (0.5% for cases, 0.3% for deaths). CONCLUSIONS: Prior to the COVID-19 pandemic, 38.5% of cancer cases and 43.4% of cancer-related deaths in Peru were linked to modifiable risk factors in the population of 15 years old and older. Most preventable cancer cases and deaths were related to oncogenic infections, primarily caused by HPV and helicobacter pylori, followed by tobacco and obesity.

SPR and Double Resonance LPG Biosensors for Helicobacter pylori BabA Antigen Detection.

Given the medical and social significance of Helicobacter pylori infection, timely and reliable diagnosis of the disease is required. The traditional invasive and non-invasive conventional diagnostic techniques have several limitations. Recently, opportunities for new diagnostic methods have appeared based on the recent advance in the study of H. pylori outer membrane proteins and their identified receptors. In the present study we assess the way in which outer membrane protein-cell receptor reactions are applicable in establishing a reliable diagnosis. Herein, as well as in other previous studies of ours, we explore the reliability of the binding reaction between the best characterized H. pylori adhesin BabA and its receptor, the blood antigen Leb. For the purpose we developed surface plasmon resonance (SPR) and double resonance long period grating (DR LPG) biosensors based on the BabA-Leb binding reaction for diagnosing H. pylori infection. In SPR detection, the sensitivity was estimated at 3000 CFU/mL-a much higher sensitivity than that of the RUT test. The DR LPG biosensor proved to be superior in terms of accuracy and sensitivity-concentrations as low as 102 CFU/mL were detected.

Helicobacter pylori glycan biosynthesis modulates host immune cell recognition and response.

Introduction: The pathogenic bacterium Helicobacter pylori has evolved glycan-mediated mechanisms to evade host immune defenses. This study tests the hypothesis that genetic disruption of H. pylori glycan biosynthesis alters immune recognition and response by human gastric epithelial cells and monocyte-derived dendritic cells. Methods: To test this hypothesis, human cell lines were challenged with wildtype H. pylori alongside an array of H. pylori glycosylation mutants. The relative levels of immune response were measured via immature dendritic cell maturation and cytokine secretion. Results: Our findings indicate that disruption of lipopolysaccharide biosynthesis diminishes gastric cytokine production, without disrupting dendritic cell recognition and activation. In contrast, variable immune responses were observed in protein glycosylation mutants which prompted us to test the hypothesis that phase variation plays a role in regulating bacterial cell surface glycosylation and subsequent immune recognition. Lewis antigen presentation does not correlate with extent of immune response, while the extent of lipopolysaccharide O-antigen elaboration does. Discussion: The outcomes of this study demonstrate that H. pylori glycans modulate the host immune response. This work provides a foundation to pursue immune-based tailoring of bacterial glycans towards modulating immunogenicity of microbial pathogens.

Continuing Medical Education Questions: April 2024.

Article Title: Effectiveness of Helicobacter pylori treatments according to antibiotic resistance.

Endoscopic findings in children born with oesophageal atresia in an academic unit in South Africa.

BACKGROUND: Oesophageal atresia (OA) is one of the most common congenital gastrointestinal (GI) abnormalities. Due to advances in multidisciplinary care, early prognosis has improved with emphasis shifting to the long-term impact of this disease. Literature suggests a higher incidence of Barrett's and eosinophilic oesophagitis in these children, with an increased risk of oesophageal carcinoma. Guidelines for adults born with OA include routine endoscopy and lifelong screening of the upper gastrointestinal tract (GIT). Despite this, uncertainty remains regarding the necessity and frequency of endoscopic surveillance for children born with OA. We describe our endoscopic findings in children born with OA. METHODS: A prospective analytic cohort study was undertaken, which included all children born with OA, that were followed-up in our unit between 2020 and 2022. History regarding feeding and GI symptoms were documented after which an endoscopy was performed. RESULTS: During the study period, 37 endoscopies were performed in patients born with OA at a median age of 25 months. The most common clinical appearance on endoscopy was anastomotic strictures followed by oesophagitis. Twelve patients had biopsies taken, with abnormal histology in all but one patient. The most common histological finding was oesophagitis with lymphocytes and chronic gastritis. Two patients had Helicobacter Pylori infection, and one had findings suggestive of eosinophilic oesophagitis. CONCLUSION: All patients with a clinical indication for an endoscopy had abnormal clinical or histological findings, thus concurring with the literature in highlighting the need for regular endoscopy. We recommend regular clinical follow-up and endoscopic surveillance if clinically indicated for children born with OA.

Seroprevalence of Helicobacter pylori infection among schoolchildren in southern Taiwan-A 20-year longitudinal follow-up.

BACKGROUND: Helicobacter pylori infection is primarily acquired in childhood and can lead to peptic ulcer diseases and gastric cancer. The prevalence of H. pylori infection varies widely in different countries. The aim of this study was to explore the change of pediatric H. pylori seroprevalence in the past two decades and to investigate the risk factors for pediatric H. pylori seropositivity in southern Taiwan. MATERIALS AND METHODS: This study enrolled children aged 7-12 years in Tainan City in 2018 and compared the result with our previous data in 1998, 2005, and 2010. Parents of the participants were invited to fill out questionnaires, including information of personal history, family history of peptic ulcer diseases, annual household income, and source of drinking water. Blood samples were analyzed for anti-H. pylori IgG by enzyme-linked immunosorbent assay. RESULTS: A total of 391, 629, 618, and 488 elementary school students in Tainan City were enrolled in 1998, 2005, 2010, and 2018, respectively. There was a significant decline in H. pylori seroprevalence from 9.2% in 1998, 7.8% in 2005, 6.2% in 2010 to 4.7% in 2018 (p < 0.001). Neither gender difference nor age difference was found in H. pylori seropositivity in each year of enrollment. Low household income was significantly associated with pediatric H. pylori seropositivity. CONCLUSIONS: The seroprevalence of H. pylori infection among elementary schoolchildren has remarkably declined in southern Taiwan in the past two decades. Low household income was a risk factor for pediatric H. pylori seropositivity.

Differential cytokine expression in gastric tissues highlights helicobacter pylori's role in gastritis.

Helicobacter pylori (H. pylori), known for causing gastric inflammation, gastritis and gastric cancer, prompted our study to investigate the differential expression of cytokines in gastric tissues, which is crucial for understanding H. pylori infection and its potential progression to gastric cancer. Focusing on Il-1ß, IL-6, IL-8, IL-12, IL-18, and TNF-α, we analysed gene and protein levels to differentiate between H. pylori-infected and non-infected gastritis. We utilised real-time quantitative polymerase chain reaction (RT-qPCR) for gene quantification, immunohistochemical staining, and ELISA for protein measurement. Gastric samples from patients with gastritis were divided into three groups: (1) non-gastritis (N-group) group, (2) gastritis without H. pylori infection (G-group), and (3) gastritis with H. pylori infection (GH-group), each consisting of 8 samples. Our findings revealed a statistically significant variation in cytokine expression. Generally, cytokine levels were higher in gastritis, but in H. pylori-infected gastritis, IL-1ß, IL-6, and IL-8 levels were lower compared to H. pylori-independent gastritis, while IL-12, IL-18, and TNF-α levels were higher. This distinct cytokine expression pattern in H. pylori-infected gastritis underscores a unique inflammatory response, providing deeper insights into its pathogenesis.

Application of cefuroxime in the eradication therapy of Helicobacter pylori infection: A review article.

BACKGROUND: Helicobacter pylori infection and its associated diseases represent a significant global health concern. Patients who cannot use amoxicillin pose a therapeutic challenge and necessitate alternative medications. Preliminary research indicates that cefuroxime demonstrates promising potential for eradicating H. pylori infection, and there is a lack of comprehensive review articles on the use of cefuroxime. MATERIALS AND METHODS: This study conducts a thorough systematic literature review and synthesis. A comprehensive systematic search was conducted in PubMed, Web of Science, EMBASE, China National Knowledge Infrastructure, China Biology Medicine disc, and Wanfang Data up to January 13, 2024. The search strategy utilized the following keywords: (Cefuroxime) AND (Helicobacter pylori OR Helicobacter nemestrinae OR Campylobacter pylori OR Campylobacter pylori subsp. pylori OR Campylobacter pyloridis OR H. pylori OR Hp) for both English and Chinese language publications. Sixteen studies from five different countries or regions were included in final literature review. RESULTS: Analysis results indicate that H. pylori is sensitive to cefuroxime, with resistance rates similar to amoxicillin being relatively low. Regimens containing cefuroxime have shown favorable eradication rates, which were comparable to those of the regimens containing amoxicillin. Regarding safety, the incidence of adverse reactions in cefuroxime-containing eradication regimens was comparable to that of amoxicillin-containing regimens or other bismuth quadruple regimens, with no significant increase in allergic reactions in penicillin-allergic patients. Regarding compliance, studies consistently report high compliance rates for regimens containing cefuroxime. CONCLUSION: Cefuroxime can serve as an alternative to amoxicillin for the patients allergic to penicillin with satisfactory efficacies, safety, and compliance.

Therapeutic efficacy and drug safety comparison of one-week Vonoprazan triple therapy with two-weeks Esomeprazole triple therapy in Helicobacter pylori infection: Findings from a single-centre randomized clinical trial in population of Pakistan.

OBJECTIVE: To compare the therapeutic efficacy and drug safety of Vonoprazan and Esomeprazole triple therapies in Helicobacter pylori infection. METHODS: The randomised clinical trial was conducted from December 2022 to January 2023 at the Department of Pharmacology, Army Medical College, National University of Medical Sciences, Rawalpindi, Pakistan, in collaboration with the Gastroenterology Department of Pak Emirates Military Hospital, Rawalpindi, and comprised patients found positive for Helicobacter pylori by stool antigen test. They were randomly distributed into two groups. The EAL group received twoweek triple therapy with Esomeprazole 20mgand Amoxicillin 1000mg twice daily with Levofloxacin 500mg once daily. The VAL group was prescribed one-week triple therapy with Vonoprazan 20mg and Amoxicillin 1000mg twice daily with Levofloxacin 500mg once daily. Eradication success was evaluated by stool antigen test 4 weeks after starting the treatment. Safety of the therapy was assessed by noting adverse effects at days 3 and 14 of the treatment. Data was analysed using SPSS 27. RESULTS: Of the 122 patients, there were 61(50%) in each of the 2 groups; 30(49.2%) males and 31(50.8%) females with mean age 38.40±12.25 years in group EAL, and 35(57.4%) males and 26(42.6%) females with mean age 40.98±12.13 years in VAL group. In the EAL group, 57(93.4%) patients were found to be free of Helicobacter pylori infection compared to 58(95%) in the VAL group. Nausea 14(23%), bitter taste 41(67.2%), abdominal pain 16(26.2%) and headache 20(32.8%) were the adverse effects that were significantly more common in the EAL group compared to the VAL group B. CONCLUSIONS: Vonoprazan-based triple therapy was found to be more effective with less reported adverse effects and potential benefits of better patient compliance due to shorter therapy duration. Clinical Trial Number: Iranian Registry of Clinical Trials: IRCT20221207056738N1.

Vonoprazan-amoxicillin dual regimen with Saccharomyces boulardii as a rescue therapy for Helicobacter pylori: Current perspectives and implications.

Yu et al's study in the World Journal of Gastroenterology (2023) introduced a novel regimen of Vonoprazan-amoxicillin dual therapy combined with Saccharomyces boulardii (S. boulardii) for the rescue therapy against Helicobacter pylori (H. pylori), a pathogen responsible for peptic ulcers and gastric cancer. Vonoprazan is a potassium-competitive acid blocker renowned for its rapid and long-lasting acid suppression, which is minimally affected by mealtime. Compared to proton pump inhibitors, which bind irreversibly to cysteine residues in the H+/K+-ATPase pump, Vonoprazan competes with the K+ ions, prevents the ions from binding to the pump and blocks acid secretion. Concerns with increasing antibiotic resistance, effects on the gut microbiota, patient compliance, and side effects have led to the advent of a dual regimen for H. pylori. Previous studies suggested that S. boulardii plays a role in stabilizing the gut barrier which improves H. pylori eradication rate. With an acceptable safety profile, the dual-adjunct regimen was effective regardless of prior treatment failure and antibiotic resistance profile, thereby strengthening the applicability in clinical settings. Nonetheless, S. boulardii comes in various formulations and dosages, warranting further exploration into the optimal dosage for supplementation in rescue therapy. Additionally, larger, randomized, double-blinded controlled trials are warranted to confirm these promising results.

Quality appraisal of clinical guidelines for Helicobacter pylori infection and systematic analysis of the level of evidence for recommendations.

OBJECTIVES: To systematically assess the quality of clinical practice guidelines (CPGs) for Helicobacter pylori (HP) infection and identify gaps that limit their development. STUDY DESIGN AND SETTING: CPGs for HP infection were systematically collected from PubMed, Embase, the Cochrane Library, the Cumulative Index to Nursing and Allied Health Literature, and six online guideline repositories. Three researchers independently used the AGREE Ⅱ tool to evaluate the methodological quality of the eligible CPGs. In addition, the reporting and recommendation qualities were appraised by using the RIGHT and AGREE-REX tools, respectively. The distribution of the level of evidence and strength of recommendation among evidence-based CPGs was determined. RESULTS: A total of 7,019 records were identified, and 24 CPGs met the eligibility criteria. Of the eligible CPGs, 19 were evidence-based and 5 were consensus-based. The mean overall rating score of AGREE II was 50.7% (SD = 17.2%). Among six domains, the highest mean score was for scope and purpose (74.4%, SD = 17.7%) and the lowest mean score was for applicability (24.3%, SD = 8.9). Only three of 24 CPGs were high-quality. The mean overall score of recommendation quality was 35.5% (SD = 12.2%), and the mean scores in each domain of AGREE-REX and RIGHT were all ≤ 60%, with values and preferences scoring the lowest (16.6%, SD = 11.9%). A total of 505 recommendations were identified. Strong recommendations accounted for 64.1%, and only 34.3% of strong recommendations were based on high-quality evidence. CONCLUSION: The overall quality of CPGs for HP infection is poor, and CPG developers tend to neglect some domains, resulting in a wide variability in the quality of the CPGs. Additionally, CPGs for HP infection lack sufficient high-quality evidence, and the grading of recommendation strength should be based on the quality of evidence. The CPGs for HP infection have much room for improvement and further researches are required to minimize the evidence gap.

Evaluation of the relationship between atherosclerosis and Helicobacter pylori infection with measurement of growth differentiation factor 15 and atherosclerosis indicators in adults with no comorbidity / Evaluación de la relación entre aterosclerosis e infección por Helicobacter pylori con medición del factor de diferenciación de crecimiento 15 e indicadores de aterosclerosis en adultos sin comorbilidad

Background The aim of this study was to investigate presence of subclinical atherosclerosis by measuring carotid intima-media thickness (CIMT) in patients with Helicobacter pylori (HP) and to assess effects of HP on atherosclerosis by evaluating markers of atherosclerosis and blood growth differentiation factor (GDF-15) levels. Materials and methods This cross-sectional study included 59 patients without comorbid disease who had HP and 30 healthy controls without HP in upper endoscopic biopsy. In order to assess atherosclerosis, the CIMT measurement was performed by sonography. Serum GDF-15 level was measured by ELISA method. In all patients, atherosclerosis markers were recorded. Atherogenic indices were calculated, including Castelli risk index I and II (TG/HDL-c and LDL-c/HDL-c, respectively), plasma atherogenic index (PAI; log TG/HDL-c), non-HDL-c (TH-HDL-c) and atherogenic coefficient (AC; non-HDL-HDL-c). Results The GDF-15 level and CIMT were significantly higher in HP-positive group when compared to HP-negative group (p≤0.001). There was a significant correlation between serum GDF-15 level and CIMT (r=0.445; p≤0.001). There was no correlation between other atherosclerosis markers and serum GDF-15 level or CIMT. The bacterial intensity on endoscopic specimen was only correlated with CIMT (p<0.001). Vitamin B12 and D levels were comparable among groups. Conclusion This study suggested that there was a correlation between GDF-15 level and subclinical atherosclerosis development in patients with HP. However, GDF-15 level, which was found to be elevated while atherogenic indices were normal, can be an earlier marker for subclinical atherosclerosis. (AU)

Antecedentes El objetivo de este estudio fue investigar la presencia de aterosclerosis subclínica mediante la medición del grosor íntima-media de la carótida (GIMC) en pacientes con Helicobacter pylori y evaluar los efectos de H.pylori sobre la aterosclerosis mediante la evaluación de marcadores de aterosclerosis y de niveles de factor de diferenciación del crecimiento sanguíneo (growth differentiation factor 15 [GDF-15]). Materiales y métodos Este estudio transversal incluyó 59 pacientes sin enfermedad comórbida que tenían H.pylori y 30 controles sanos sin H.pylori en la biopsia endoscópica superior. Para evaluar la aterosclerosis, la medición de GIMC se realizó mediante ecografía. El nivel de GDF-15 en suero se midió mediante el método ELISA. En todos los pacientes se registraron marcadores de aterosclerosis. Se calcularon los índices aterogénicos, incluyendo el índice de riesgo de Castelli I y II (TG/cHDL y cLDL-cHDL, respectivamente), el índice aterogénico plasmático (PAI; log TG/HDL-c), no-cHDL (TH-cHDL) y el coeficiente aterogénico (no-HDL-cHDL). Resultados Los niveles de GDF-15 y de GIMC fueron significativamente más altos en el grupo H.pylori positivo en comparación con el grupo H.pylori negativo (p≤0,001). Hubo una fuerte correlación entre el nivel sérico de GDF-15 y el GIMC (r=0,445; p≤0,001). No hubo correlación entre otros marcadores de aterosclerosis y el nivel sérico de GDF-15 o GIMC. La intensidad bacteriana en la muestra endoscópica solo se correlacionó con GIMC (p≤0,001). Los niveles de vitaminaB12 y de vitaminaD fueron comparables entre los grupos. Conclusión Este estudio sugirió que había una correlación entre el nivel de GDF-15 y el desarrollo de aterosclerosis subclínica en pacientes con H.pylori. Sin embargo, el nivel de GDF-15, que se encontró elevado mientras que los índices aterogénicos eran normales, puede ser un marcador temprano de aterosclerosis subclínica. (AU)

Chitosan-LeoA-DNA Nanoparticles Promoted the Efficacy of Novel LeoA-DNA Vaccination on Mice Against Helicobacter pylori.

More than half of the world's population is infected with Helicobacter pylori (H. pylori), which may lead to chronic gastritis, peptic ulcers, and stomach cancer. LeoA, a conserved antigen of H. pylori, aids in preventing this infection by triggering specific CD3+ T-cell responses. In this study, recombinant plasmids containing the LeoA gene of H. pylori are created and conjugated with chitosan nanoparticle (CSNP) to immunize BALB/c mice against the H. pylori infection. We used the online Vaxign tool to analyze the genomes of five distinct strains of H. pylori, and we chose the outer membrane as a prospective vaccine candidate. Afterward, the proteins' immunogenicity was evaluated. The DNA vaccine was constructed and then encapsulated in CSNPs. The effectiveness of the vaccine's immunoprotective effects was evaluated in BALB/c mice. Purified activated splenic CD3+ T cells are used to test the anticancer effects in vitro. Nanovaccines had apparent spherical forms, were small (mean size, 150-250 nm), and positively charged (41.3 ± 3.11 mV). A consistently delayed release pattern and an entrapment efficiency (73.35 ± 3.48%) could be established. Compared to the non-encapsulated DNA vaccine, vaccinated BALB/c mice produced higher amounts of LeoA-specific IgG in plasma and TNF-α in splenocyte lysate. Moreover, BALB/c mice inoculated with nanovaccine demonstrated considerable immunity (87.5%) against the H. pylori challenge and reduced stomach injury and bacterial burdens in the stomach. The immunological state in individuals with GC with chronic infection with H. pylori is mimicked by the H. pylori DNA nanovaccines by inducing a shift from Th1 to Th2 in the response. In vitro human GC cell development is inhibited by activated CD3+ T lymphocytes. According to our findings, the H. pylori vaccine-activated CD3+ has potential immunotherapeutic benefits.

The Gut Microbiota in Parkinson Disease: Interactions with Drugs and Potential for Therapeutic Applications.

The concept of a 'microbiota-gut-brain axis' has recently emerged as an important player in the pathophysiology of Parkinson disease (PD), not least because of the reciprocal interaction between gut bacteria and medications. The gut microbiota can influence levodopa kinetics, and conversely, drugs administered for PD can influence gut microbiota composition. Through a two-step enzymatic pathway, gut microbes can decarboxylate levodopa to dopamine in the small intestine and then dehydroxylate it to m-tyramine, thus reducing availability. Inhibition of bacterial decarboxylation pathways could therefore represent a strategy to increase levodopa absorption. Other bacterial perturbations common in PD, such as small intestinal bacterial overgrowth and Helicobacter pylori infection, can also modulate levodopa metabolism, and eradication therapies may improve levodopa absorption. Interventions targeting the gut microbiota offer a novel opportunity to manage disabling motor complications and dopa-unresponsive symptoms. Mediterranean diet-induced changes in gut microbiota composition might improve a range of non-motor symptoms. Prebiotics can increase levels of short-chain fatty acid-producing bacteria and decrease pro-inflammatory species, with positive effects on clinical symptoms and levodopa kinetics. Different formulations of probiotics showed beneficial outcomes on constipation, with some of them improving dopamine levels; however, the most effective dosage and duration and long-term effects of these treatments remain unknown. Data from faecal microbiota transplantation studies are preliminary, but show encouraging trends towards improvement in both motor and non-motor outcomes.This article summarises the most up-to-date knowledge in pharmacomicrobiomics in PD, and discusses how the manipulation of gut microbiota represents a potential new therapeutic avenue for PD.

Evaluating the potency of zoliflodacin against Helicobacter pylori: In vitro activity and conserved GyrB target.

BACKGROUND: The current standard treatment for Helicobacter pylori infection, which involves a combination of two broad-spectrum antibiotics, faces significant challenges due to its detrimental impact on the gut microbiota and the emergence of drug-resistant strains. This underscores the urgent requirement for the development of novel anti-H. pylori drugs. Zoliflodacin, a novel bacterial gyrase inhibitor, is currently undergoing global phase III clinical trials for treating uncomplicated Neisseria gonorrhoeae. However, there is no available data regarding its activity against H. pylori. MATERIALS AND METHODS: We evaluated the in vitro activity of zoliflodacin against H. pylori clinical isolates (n = 123) with diverse multidrug resistance. We performed DNA gyrase supercoiling and microscale thermophoresis assays to identify the target of zoliflodacin in H. pylori. We analyzed 2262 H. pylori whole genome sequences to identify Asp424Asn and Lys445Asn mutations in DNA gyrase subunit B (GyrB) that are associated with zoliflodacin resistance. RESULTS: Zoliflodacin exhibits potent activity against all tested isolates, with minimal inhibitory concentration (MIC) values ranging from 0.008 to 1 µg/mL (MIC50: 0.125 µg/mL; MIC90: 0.25 µg/mL). Importantly, there was no evidence of cross-resistance to any of the four first-line antibiotics commonly used against H. pylori. We identified GyrB as the primary target of zoliflodacin, with Asp424Asn or Lys445Asn substitutions conferring resistance. Screening of 2262 available H. pylori genomes for the two mutations revealed only one clinical isolate carrying Asp424Asn substitution. CONCLUSION: These findings support the potential of zoliflodacin as a promising candidate for H. pylori treatment, warranting further development and evaluation.

Type 2 Diabetes Mellitus and Helicobacter pylori Eradication in a Clinical Population.

OBJECTIVES: Eradication of Helicobacter pylori reduces the risk of gastric cancer (GC). Individuals with type 2 diabetes mellitus (T2DM) are known to be at increased risk for GC. In a cohort of H. pylori-positive individuals, we assessed whether those with T2DM were at risk of persistent infection following H. pylori treatment compared with individuals without T2DM. METHODS: A random subset of all individuals diagnosed as having H. pylori without intestinal metaplasia at endoscopy from 2015 to 2019 were stratified evenly by race (Black and White). After excluding those with T1DM and those without eradication testing after H. pylori treatment, logistic regression analysis was used to determine the association of T2DM with the risk of persistent H. pylori infection following treatment. RESULTS: In 138 patients, H. pylori eradication rates did not differ between the 27% of individuals with T2DM compared to those without (81.1% vs 81.2%). After adjusting for age, race, and insurance status, we found no significant increased risk of persistent H. pylori infection for individuals with T2DM (odds ratio 1.40; 95% confidence interval 0.49-3.99). CONCLUSIONS: H. pylori eradication rates do not differ by T2DM status, providing support for clinical trials of H. pylori eradication to reduce GC incidence among high-risk populations in the United States, such as individuals with T2DM.

Fourteen-day vonoprazan-based bismuth quadruple therapy for H. pylori eradication in an area with high clarithromycin and levofloxacin resistance: a prospective randomized study (VQ-HP trial).

Potassium-competitive acid blockers (P-CABs) provide potent acid inhibition, yet studies on P-CAB-based quadruple therapy for H. pylori eradication are limited. We theorized that integrating bismuth subsalicylate into a quadruple therapy regimen could enhance eradication rates. However, data on the efficacy of vonoprazan bismuth quadruple therapy are notably scarce. Therefore, the aim of this study was to evaluate the efficacy of vonoprazan-based bismuth quadruple therapy in areas with high clarithromycin and levofloxacin resistance. This was a prospective, single-center, randomized trial conducted to compare the efficacy of 7-day and 14-day vonoprazan-based bismuth quadruple therapy for H. pylori eradication between June 1, 2021, and March 31, 2022. Qualified patients were randomly assigned to the 7-day or 14-day regimen (1:1 ratio by computer-generated randomized list as follows: 51 patients for the 7-day regimen and 50 patients for the 14-day regimen). The regimens consisted of vonoprazan (20 mg) twice daily, bismuth subsalicylate (1024 mg) twice daily, metronidazole (400 mg) three times daily, and tetracycline (500 mg) four times daily. CYP3A4/5 genotyping and antibiotic susceptibility tests were also performed. Successful eradication was defined as 13negative C-UBTs 4 weeks after treatment. The primary endpoint was to compare the efficacy of 7-day and 14-day regimens as first-line treatments, which were assessed by intention-to-treat (ITT) and per-protocol (PP) analyses. The secondary endpoints included adverse effects. A total of 337 dyspeptic patients who underwent gastroscopy were included; 105 patients (31.1%) were diagnosed with H. pylori infection, and 101 patients were randomly assigned to each regimen. No dropouts were detected. The antibiotic resistance rate was 33.3% for clarithromycin, 29.4% for metronidazole, and 27.7% for levofloxacin. The CYP3A4 genotype was associated with 100% rapid metabolism. The H. pylori eradication rates for the 7-day and 14-day regimens were 84.4%, 95% CI 74.3-94.2 and 94%, 95% CI 87.4-100, respectively (RR difference 0.25, 95% CI 0.03-0.53, p value = 0.11). Interestingly, the 14-day regimen led to 100% eradication in the clarithromycin-resistant group. Among the patients in the 7-day regimen group, only two exhibited resistance to clarithromycin; unfortunately, neither of them achieved a cure from H. pylori infection. The incidence of adverse events was similar in both treatment groups, occurring in 29.4% (15/51) and 28% (14/50) of patients in the 7-day and 14-day regimens, respectively. No serious adverse reactions were reported. In conclusion, 14 days of vonoprazan-based bismuth quadruple therapy is highly effective for H. pylori eradication in areas with high levels of dual clarithromycin and levofloxacin resistance.