Helicobacter pylori and neurological diseases: Married by the laws of inflammation

Co-Occurrence of Helicobacter pylori and Candida spp. Infections in the Pathogenesis of Gastrointestinal Diseases

Helicobacter pylori and Candida spp. are widespread microorganisms found in the human gastrointestinal tract, often coexisting in the same ecological niche. H. pylori, a Gram-negative bacterium, is a well-known pathogen responsible for gastritis, peptic ulcers, and gastric cancer. In contrast, Candida fungi, often detected in food, particularly Candida albicans, are generally considered commensal organisms, but can become opportunistic pathogens under certain conditions. Recent studies suggest a possible link between these microorganisms, highlighting a new survival strategy of H. pylori, that is, its ability to internalize in Candida vacuoles. This phenomenon, confirmed by various microscopic and molecular techniques, may provide H. pylori with protection against adverse environmental conditions, especially clinically important antibiotic therapy. The basic premise of this theory is the ability of H. pylori to penetrate vacuoles in fungal cells, which then become a reservoir of infection, allowing the infection to recur. Understanding the interaction between H. pylori and Candida may offer new insights into the pathogenesis of gastrointestinal diseases and may lead to the development of treatments targeting both organisms simultaneously. The purpose of this article is to review the literature, considering the first observations on this problem in the literature and the current state of knowledge, and to suggest a direction for further research.

Untargeted metabolomic profiling for identifying systemic signatures of helicobacter pylori infection in a guinea pig model

Infections caused by the Gram-negative bacterium Helicobacter pylori (H. pylori) can lead to gastritis, gastric or duodenal ulcers, and even gastric cancer in humans. Investigating quantitative changes in soluble biomarkers associated with H. pylori infection offers a promising method for monitoring the progression of the infection, inflammatory response and potentially systemic consequences. This study aimed to identify, using an experimental model of H. pylori infection in guinea pigs, the specific metabolomic biomarkers in the serum of H. pylori-infected (32) versus uninfected (32) animals. The H. pylori status was confirmed through histological, molecular, and serological examinations. Metabolomic profiling was conducted using UPLC-QTOF/MS methods. The metabolomic biomarkers significantly associated with H. pylori infection were selected based on volcano plots and traditional univariate receiver operating characteristics (ROC). This study identified 12 unique metabolites significantly differentiating H. pylori-infected guinea pigs from uninfected ones. In summary, the metabolomic profiling of serum samples, in combination with ROC characteristics of the data, enhances the monitoring of H. pylori infection and related inflammatory responses in guinea pigs experimentally infected with these bacteria, with potential applications in humans for prediction the infection course and its systemic effects.

Extracellular vesicles in Helicobacter pylori-mediated diseases: mechanisms and therapeutic potential

Extracellular vesicles (EVs) are relevant elements for cell-to-cell communication and are considered crucial in host-pathogen interactions by transferring molecules between the pathogen and the host during infections. These structures participate in various physiological and pathological processes and are considered promising candidates as disease markers, therapeutic reagents, and drug carriers. Both H. pylori and the host epithelial cells infected by H. pylori secrete EVs, which contribute to inflammation and the development of disease phenotypes. However, many aspects of the cellular and molecular biology of EV functions remain incompletely understood due to methodological challenges in studying these small structures. This review also highlights the roles of EVs derived from H. pylori-infected cells in the pathogenesis of gastric and extragastric diseases. Understanding the specific functions of these EVs during H. pylori infections, whether are advantageous to the host or the pathogen, may help the development new therapeutic approaches to prevent disease.

Microbial Trojan Horses: Virulence Factors as Key Players in Neurodegenerative Diseases

Changes in population demographics indicate that the elderly population will reach 2.1 billion worldwide by 2050. In parallel, there will be an increase in neurodegenerative diseases such as Alzheimer's and Parkinson's. This review explores dysbiosis occurring in these pathologies and how virulence factors contribute to the worsening or development of clinical conditions, and it summarizes existing and potential ways to combat microorganisms related to these diseases. Microbiota imbalances can contribute to the progression of neurodegenerative diseases by increasing intestinal permeability, exchanging information through innervation, and even acting as a Trojan horse affecting immune cells. The microorganisms of the microbiota produce virulence factors to protect themselves from host defenses, many of which contribute to neurodegenerative diseases. These virulence factors are expressed according to the genetic composition of each microorganism, leading to a wide range of factors to be considered. Among the main virulence factors are LPS, urease, curli proteins, amyloidogenic proteins, VacA, and CagA. These factors can also be packed into bacterial outer membrane vesicles, which transport proteins, RNA, and DNA, enabling distal communication that impacts various diseases, including Alzheimer's and Parkinson's.

Natural products: Harnessing the power of gut microbiota for neurological health

BACKGROUND

Neurological diseases are the primary cause of disability and death and impose substantial financial burdens. However, existing treatments only relieve symptoms and may cause many adverse effects. Natural products are a promising source of neurological therapeutic agents due to their excellent neuroprotective effect and safety. The gut microbiota has an essential impact on maintaining brain homeostasis via the gut-brain axis. Multiple investigations show that natural products offer neuroprotective effects by regulating gut microbiota-driven signaling networks.

OBJECTIVES

This review aims to provide a systematic review of how natural products promote neurological health by harnessing the power of gut microbiota.

METHODS

The pre-January 1, 2024 literature was gathered from several databases, including Scopus, PubMed, Google Scholar, and Web of Science, utilizing appropriate keywords. The gathered publications underwent a review process and were classified based on their study content, specifically focusing on the impact of natural products on gut microbiota and neurological health.

RESULTS

Here, we review how natural products promote neurological health by regulating the gut microbiota-brain axis. Specifically, we focus on the following areas. (1) Altering microorganism community structure, including increasing α-diversity and altering β-diversity. (2) Regulating the population of certain bacteria, including enriching beneficial microorganisms Akkermansia and Bifidobacterium, and inhibiting potentially hazardous microorganisms Bilophila, Klebsiella, and Helicobacter. (3) Regulating microbial neuroactive metabolites levels, including short-chain fatty acids, tryptophan and its derivatives, trimethylamine N-oxide, dopa/dopamine, γ-aminobutyric acid, and lipopolysaccharide. Furthermore, we review how natural products promote neurological health by regulating intestinal barrier homeostasis.

CONCLUSION

Natural products promote neurological health by harnessing the power of gut microbiota. This review will contribute to understanding how natural products promote neurological health by orchestrating the gut microbiota-brain axis.

Fecal microbiota transplantation for glaucoma; a potential emerging treatment strategy

Glaucoma is the primary cause of irreversible blindness globally. Different glaucoma subtypes are identified by their underlying mechanisms, and treatment options differ by its pathogenesis. Current management includes topical medications to lower intraocular pressure and surgical procedures like trabeculoplasty and glaucoma drainage implants. Fecal microbiota transplantation (FMT) is an almost effective and safe treatment option for recurrent Clostridium difficile infection. The relationship between bacterial populations, metabolites, and inflammatory pathways in retinal diseases indicates possible therapeutic strategies. Thus, incorporating host microbiota-based therapies could offer an additional treatment option for glaucoma patients. Here, we propose that combining FMT with standard glaucoma treatments may benefit those affected by this condition. Also, the potential safety, efficacy, cost-effectiveness and clinical applications are discussed.

MAD-microbial (origin of) Alzheimer's disease hypothesis: from infection and the antimicrobial response to disruption of key copper-based systems

Microbes have been suspected to cause Alzheimer's disease since at least 1908, but this has generally remained unpopular in comparison to the amyloid hypothesis and the dominance of Aβ and Tau. However, evidence has been accumulating to suggest that these earlier theories are but a manifestation of a common cause that can trigger and interact with all the major molecular players recognized in AD. Aβ, Tau and ApoE, in particular appear to be molecules with normal homeostatic functions but also with alternative antimicrobial functions. Their alternative functions confer the non-immune specialized neuron with some innate intracellular defenses that appear to be re-appropriated from their normal functions in times of need. Indeed, signs of infection of the neurons by biofilm-forming microbial colonies, in synergy with herpes viruses, are evident from the clinical and preclinical studies we discuss. Furthermore, we attempt to provide a mechanistic understanding of the AD landscape by discussing the antimicrobial effect of Aβ, Tau and ApoE and Lactoferrin in AD, and a possible mechanistic link with deficiency of vital copper-based systems. In particular, we focus on mitochondrial oxidative respiration via complex 4 and ceruloplasmin for iron homeostasis, and how this is similar and possibly central to neurodegenerative diseases in general. In the case of AD, we provide evidence for the microbial Alzheimer's disease (MAD) theory, namely that AD could in fact be caused by a long-term microbial exposure or even long-term infection of the neurons themselves that results in a costly prolonged antimicrobial response that disrupts copper-based systems that govern neurotransmission, iron homeostasis and respiration. Finally, we discuss potential treatment modalities based on this holistic understanding of AD that incorporates the many separate and seemingly conflicting theories. If the MAD theory is correct, then the reduction of microbial exposure through use of broad antimicrobial and anti-inflammatory treatments could potentially alleviate AD although this requires further clinical investigation.

Bacterial Insights: Unraveling the Ocular Microbiome in Glaucoma Pathogenesis

This review explores the connection between the ocular surface microbiome and glaucoma, highlighting its impact on disease progression. Beginning with an overview of global glaucoma significance, it emphasizes the importance of understanding the cellular characteristics and microbiology of the ocular microbiome. A search was conducted on the PubMed and Cochrane Library databases using the phrase "ocular microbiome glaucoma". 0 records were returned from the Cochrane Library while 21 were returned from PubMed. A total of 21 results were retrieved from 2017 to 2024. This comprised one opinion paper, four original research articles, and 16 reviews. This review covered the anatomy of the ocular surface, advanced analysis methods, and the ocular microbiome. It also delved into dysbiosis in glaucoma, addressing altered microbial communities and their potential role in disease progression. The intricate interplay between the ocular microbiome and the host's immune system is explored, emphasizing crosstalk and inflammatory responses. The review concludes by discussing therapeutic implications, including modulating ocular microbiota and potential future treatment strategies. Understanding the microbiome in healthy and glaucomatous eyes can help researchers and clinicians in innovative approaches to ocular health.

Cardiovascular and Neurological Diseases and Association with Helicobacter Pylori Infection-An Overview

This article investigates the link between Helicobacter pylori (H. pylori) infection and cardiovascular and neurological disorders. Recent research suggests that H. pylori may play a role in cardiovascular diseases like atherosclerosis, myocardial infarction, and stroke, as well as neurological diseases including Alzheimer's disease, multiple sclerosis, and Parkinson's disease. Cardiovascular Diseases: H. pylori induces endothelial dysfunction and chronic inflammation, promoting atherosclerotic plaque formation and other cardiac complications. High infection prevalence in cardiovascular patients implies that systemic inflammation from H. pylori accelerates disease progression. Eradication therapies combined with anti-inflammatory and lipid-lowering treatments may reduce cardiovascular risk. Neurological Diseases: H. pylori may contribute to Alzheimer's, multiple sclerosis, and Parkinson's through systemic inflammation, neuroinflammation, and autoimmune responses. Increased infection prevalence in these patients suggests bacterial involvement in disease pathogenesis. The eradication of H. pylori could reduce neuroinflammation and improve outcomes. Discussions and Future Research: Managing H. pylori infection in clinical practice could impact public health and treatment approaches. Further research is needed to clarify these relationships. Longitudinal and mechanistic studies are essential to fully understand H. pylori's role in these conditions. Conclusions: H. pylori infection is a potential risk factor for various cardiovascular and neurological conditions. Additional research is critical for developing effective prevention and treatment strategies. Targeted therapies, including H. pylori eradication combined with anti-inflammatory treatments, could improve clinical outcomes. These findings highlight the need for an integrated clinical approach to include H. pylori evaluation and treatment.

Research progress on Helicobacter pylori infection related neurological diseases

Helicobacter pylori, a type of gram-negative bacterium, infects roughly half of the global population. It is strongly associated with gastrointestinal disorders like gastric cancer, peptic ulcers, and chronic gastritis. Moreover, numerous studies have linked this bacterium to various extra-gastric conditions, including hematologic, cardiovascular, and neurological issues. Specifically, research has shown that Helicobacter pylori interacts with the brain through the microbiota-gut-brain axis, thereby increasing the risk of neurological disorders. The inflammatory mediators released by Helicobacter pylori-induced chronic gastritis may disrupt the function of the blood-brain barrier by interfering with the transmission or direct action of neurotransmitters. This article examines the correlation between Helicobacter pylori and a range of conditions, such as hyperhomocysteinemia, schizophrenia, Alzheimer's disease, Parkinson's disease, ischemic stroke, multiple sclerosis, migraine, and Guillain-Barré syndrome.

The role of digestive system diseases in cerebrovascular disease: a comprehensive Mendelian randomization study

Background

Cerebrovascular disease, among the most prevalent neurological disorders, poses a substantial threat to human health with its elevated mortality and disability rates, placing considerable strain on healthcare systems. Although several studies in recent years have suggested a potential association between digestive system diseases and cerebrovascular diseases, the findings remain inconsistent.

Methods

Genome-wide association study (GWAS) summary data for 12 digestive diseases and cerebrovascular diseases were used to conduct Mendelian randomization (MR) analysis. In this investigation, we endeavored to elucidate the causal relationship between digestive system diseases and cerebrovascular diseases. Employing a comprehensive approach, including two-sample MR (TSMR), multivariate MR (MVMR), and two-step MR analysis, we leveraged summary statistics data obtained from published GWAS. The primary analysis method employed was inverse variance weighted (IVW), with MR-Egger and weighted median (WM) as secondary methods. Sensitivity analysis included heterogeneity testing, horizontal multivariate testing, MR-PRESSO, and a "leave-one-out" method. Additionally, the F-statistic was utilized to assess the strength of instrumental variables, ensuring robust results.

Results

In the TSMR analysis, this study found a significant causal relationship between genetically predicted gastroesophageal reflux disease (GERD) and any stroke (AS), any ischemic stroke (AIS), large-artery atherosclerotic stroke (LAS), intracranial aneurysm (IA), and subarachnoid hemorrhage (SAH). In MVMR analysis, this study found that even after adjusting for systolic blood pressure (SBP), body mass index (BMI) and type 2 diabetes (T2D), the causal relationship remains exist. In the two-step MR mediation analysis, it was found that BMI, SBP and T2D play mediating role in the causal relationship between GERD and cerebrovascular diseases.

Conclusion

This study indicates a clear positive causal relationship between GERD and cerebrovascular diseases, and this causal association remains significant even after adjusting for BMI, SBP and T2D. The mediation MR analysis suggests that BMI, SBP and T2D may mediate the causal relationship between GERD and the risk of cerebrovascular diseases.

Gut microbiota compositional profile in patients with posner-schlossman syndrome

The cause of Posner-Schlossman syndrome (PSS) remains unknown and its frequent recurrence may eventually lead to irreversible damage of the optic nerve. The influence of immune factors in the pathophysiology of PSS is gaining more and more interest. Increasing evidence suggests that gut dysbiosis plays vital roles in a variety of neurodegenerative and immune-related diseases. However, alterations of the gut microbiota in PSS patients have not been well defined yet. In this study, 16S rRNA sequencing was used to explore the difference of gut microbiota between PSS patients and healthy controls, and the correlation between the microbiota profile and clinical features was also analyzed. Our data demonstrated a significant increase of Prevotella and Prevotellaceae, and a significant reduction of Bacteroides and Bacteroidaceae in PSS patients, and KEGG analysis showed dysfunction of gut microbiota between PSS patients and healthy controls. Interestingly, further analysis showed that the alteration of gut microbiota was correlated with the PSS attack frequency of PSS. This study demonstrated the gut microbiota compositional profile of PSS patients and speculated the risk microbiota of PSS, which is expected to provide new insights for the diagnosis and treatment of PSS.

The first Helicobacter pylori-induced Guillain-Barré syndrome in Sudan

Key Clinical Message

This case report highlights the role of Helicobacter pylori infection in the development of GBS. Healthcare providers should consider H. pylori in their differential diagnosis for patients with neurological syndromes.

Astract

We report the first known case of Guillain-Barré syndrome (GBS) associated with Helicobacter pylori infection in Sudan. This case highlights the role of H. pylori infection in the development of GBS. It also emphasizes the importance of wide screening of different endemic infections for patients with neurological syndromes for early detection and improves the case management in resource-limited settings like Sudan. Further research is needed to better understand the underlying mechanisms of H. pylori-inducing neurological disorders.

Could the Urease of the Gut Bacterium Proteus mirabilis Play a Role in the Altered Gut-Brain Talk Associated with Parkinson's Disease?

Intestinal dysbiosis seems to play a role in neurodegenerative pathologies. Parkinson's disease (PD) patients have an altered gut microbiota. Moreover, mice treated orally with the gut microbe Proteus mirabilis developed Parkinson's-like symptoms. Here, the possible involvement of P. mirabilis urease (PMU) and its B subunit (PmUreβ) in the pathogenesis of PD was assessed. Purified proteins were given to mice intraperitoneally (20 μg/animal/day) for one week. Behavioral tests were conducted, and brain homogenates of the treated animals were subjected to immunoassays. After treatment with PMU, the levels of TNF-α and IL-1β were measured in Caco2 cells and cellular permeability was assayed in Hek 293. The proteins were incubated in vitro with α-synuclein and examined via transmission electron microscopy. Our results showed that PMU treatment induced depressive-like behavior in mice. No motor deficits were observed. The brain homogenates had an increased content of caspase-9, while the levels of α-synuclein and tyrosine hydroxylase decreased. PMU increased the pro-inflammatory cytokines and altered the cellular permeability in cultured cells. The urease, but not the PmUreβ, altered the morphology of α-synuclein aggregates in vitro, forming fragmented aggregates. We concluded that PMU promotes pro-inflammatory effects in cultured cells. In vivo, PMU induces neuroinflammation and a depressive-like phenotype compatible with the first stages of PD development.

Gasdermin D kills bacteria

The recognition of pathogen- or damage- associated molecular patterns (PAMPs/DAMPs) signals a series of coordinated responses as part of innate immunity or host cell defense during infection. The inflammasome is an assemblage of multiprotein complexes in the cytosol that activate inflammatory caspases and release pro-inflammatory mediators. This review examines the two-edged sword activity of gasdermin D (GSDMD). Since its discovery in 2015, GSDMD has played a crucial role in the programmed necrotic type of cell death called pyroptosis. Pyroptosis is an important response in host self-protection against danger signals and infection. Although excessive pyroptosis has a deleterious effect on the host, it proves to have a game-changing therapeutic application against pathogenic invasion when controlled. Here, we explore the mechanism utilized by GSDMD, the best studied member of the gasdermin protein family, in host immune defense against many bacteria. While the protein contributes to the clearance of some bacteria, we also discussed results from previous studies and research, that its presence might hinder effective immunity against other pathogens, thus aiding pathogenic invasion and spread.

The Endotoxin Hypothesis of Parkinson's Disease

The endotoxin hypothesis of Parkinson's disease (PD) is the idea that lipopolysaccharide (LPS) endotoxins contribute to the pathogenesis of this disorder. LPS endotoxins are found in, and released from, the outer membrane of Gram-negative bacteria, for example in the gut. It is proposed that gut dysfunction in early PD leads to elevated LPS levels in the gut wall and blood, which promotes both α-synuclein aggregation in the enteric neurons and a peripheral inflammatory response. Communication to the brain via circulating LPS and cytokines in the blood and/or the gut-brain axis leads to neuroinflammation and spreading of α-synuclein pathology, exacerbating neurodegeneration in brainstem nuclei and loss of dopaminergic neurons in the substantia nigra, and manifesting in the clinical symptoms of PD. The evidence supporting this hypothesis includes: (1) gut dysfunction, permeability, and bacterial changes occur early in PD, (2) serum levels of LPS are increased in a proportion of PD patients, (3) LPS induces α-synuclein expression, aggregation, and neurotoxicity, (4) LPS causes activation of peripheral monocytes leading to inflammatory cytokine production, and (5) blood LPS causes brain inflammation and specific loss of midbrain dopaminergic neurons, mediated by microglia. If the hypothesis is correct, then treatment options might include: (1) changing the gut microbiome, (2) reducing gut permeability, (3) reducing circulating LPS levels, or (4) blocking the response of immune cells and microglia to LPS. However, the hypothesis has a number of limitations and requires further testing, in particular whether reducing LPS levels can reduce PD incidence, progression, or severity. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Preventive effect of Helicobacter pylori eradication on the coronary heart diseases depending on age and sex with a median follow-up of 51 months

BACKGROUND

The association between Helicobacter pylori (HP) infection and coronary heart disease (CHD) is controversial. This study aimed to investigate the effect of H. pylori eradication on CHD, especially in terms of age and sex.

MATERIALS AND METHODS

From May 2003 to March 2022, 4765 subjects with H. pylori infection and without CHD (median follow-up: 51 months) were prospectively enrolled. The participants were categorized into two groups: H. pylori eradication and H. pylori non-eradication. After propensity-score matching (PSM), the effect of H. pylori eradication on CHD was analyzed using Cox proportional hazards.

RESULTS

There were no significant differences in age, sex, alcohol consumption, smoking habits, history of diabetes, hypertension, and dyslipidemia, and aspirin intake between the eradication and non-eradication groups (3783 vs. 982) before and after PSM. Multivariate analysis after PSM showed that H. pylori eradication (HR: 0.489, CI: 0.314-0.761, p = .002), age (HR: 1.027, CI: 1.007-1.047, p = .007), hypertension (HR: 2.133, CI: 1.337-3.404, p = 001), dyslipidemia (HR: 1.758, CI: 1.086-2.848, p = .022), and aspirin intake (HR: 2.508, CI: 1.566-4.017, p < .001) were associated with CHD development. H. pylori eradication prevented CHD in males ≤65 years (HR: 0.133, CI: 0.039-0.455, p = .001), but not in those aged >65 years (p = .078) (p for interaction = .022). In contrast, females aged >65 years (HR: 0.260, CI: 0.110-0.615, p = .002) were protected by H. pylori eradication and not those ≤65 years (p = .485) (p for interaction = .003). This preventive effect increased more after PSM, particularly in males ≤65 years and females >65 years.

CONCLUSIONS

H. pylori eradication prevented CHD and this effect was different depending on age and sex.

Long-term Effects of the Eradication of Helicobacter pylori on Metabolic Parameters, Depending on Sex, in South Korea

Background/Aims

Helicobacter pylori (HP) infection is positively associated with metabolic syndrome (MS). However, the long-term effects of eradication therapy on MS and sex differences have not been thoroughly studied. We aimed to investigate the long-term effects of HP eradication on MS and sex differences.

Methods

This study included 2,267 subjects who visited a tertiary referral center between May 2003 and May 2019. HP was diagnosed by histology, a Campylobacter-like organism test, and culture, and the subjects were prospectively followed up. The participants were categorized into three groups: HP uninfected, HP infected but non-eradicated, and HP eradicated. The baseline characteristics and changes in metabolic parameters after HP eradication were compared over a 5-year follow-up period.

Results

Among 1,521 subjects, there was no difference in baseline metabolic parameters between the HP-uninfected (n=509) and HP-infected (n=1,012) groups, regardless of sex. Analysis of the metabolic parameters during follow-up among HP-uninfected (n=509), HP-non-eradicated (n=346), and HP-eradicated (n=666) groups showed that high-density lipoprotein (HDL) and the body mass index (BMI) increased after eradication, with a significant difference at 1-year of follow-up. In females, HDL increased after eradication (p=0.023), and the BMI increased after eradication in male subjects (p=0.010). After propensity score matching, the HDL change in female remained significant, but the statistical significance of the change in BMI in the male group became marginally significant (p=0.089).

Conclusions

HP eradication affected metabolic parameters differently depending on sex. HDL significantly increased only in females over time, especially at 1-year of follow-up. In contrast, BMI showed an increasing tendency over time in males, especially at the 1-year follow-up.

Helicobacter pylori infection: is there circulating vacuolating cytotoxin A or cytotoxin-associated gene A protein?

BACKGROUND

Helicobacter pylori infection is a well-recognized cause of gastric diseases, including chronic gastritis, peptic ulcer, and gastric cancer. Vacuolating cytotoxin-A (VacA) and cytotoxin-associated gene A protein (CagA) play a role in the pathogenesis of H. pylori-related gastric diseases. Also, extragastric disorders are frequent morbid complications in patients with H. pylori infection. However, the direct pathologic implication of these virulence factors in extragastric manifestations remains unclear. Our hypothesis in the present study is that VacA and CagA released by H. pylori in the gastric mucosa leak into the systemic circulation, and therefore they can be measured in serum.

RESULTS

Sixty-two subjects were enrolled. They were allocated into the H. pylori-positive and H. pylori-negative groups. VacA and CagA were measured by immunoassays. The serum levels of VacA and CagA above an upper limit cut-off (mean plus two standard deviations of the mean in patients without H. pylori infection) were considered positive for antigen circulating level. Five out of 25 H. pylori-positive patients were positive for both serum VacA and serum CagA. The serum levels of VacA and CagA were significantly correlated with the serum levels of anti- H. pylori antibody and interleukin-12p70 among all H. pylori-positive and H. pylori-negative patients.

CONCLUSIONS

This study suggests that spill-over of VacA and CagA antigens in the systemic circulation may occur in some patients with H. pylori infection.

Differential Proteomics of Helicobacter pylori Isolates from Gastritis, Ulcer, and Cancer Patients: First Study from Northwest Pakistan

Background and Objective: Helicobacter pylori is a human-stomach-dwelling organism that causes many gastric illnesses, including gastritis, ulcer, and gastric cancer. The purpose of the study was to perform differential proteomic analysis on H. pylori isolates from gastritis, ulcer, and gastric cancer patients. Materials and Methods: H. pylori was isolated from antrum and fundus biopsies obtained from patients who visited the Department of Gastroenterology. Using nano-LC-QTOF MS/MS analysis, differentially regulated proteins were identified through proteome profiling of pooled samples of H. pylori isolated from gastritis, ulcer, and gastric cancer patients. Antigenic scores and cellular localization of proteins were determined using additional prediction tools. Results: A total of 14 significantly regulated proteins were identified in H. pylori isolated from patients with either gastritis, ulcer, or gastric cancer. Comparative analysis of groups revealed that in the case of cancer vs. gastritis, six proteins were overexpressed, out of which two proteins, including hydrogenase maturation factor (hypA) and nucleoside diphosphate kinase (ndk) involved in bacterial colonization, were only upregulated in isolates from cancer patients. Similarly, in cancer vs. ulcer, a total of nine proteins were expressed. Sec-independent protein translocase protein (tatB), involved in protein translocation, and pseudaminic acid synthase I (pseI), involved in the synthesis of functional flagella, were upregulated in cancer, while hypA and ndk were downregulated. In ulcer vs. gastritis, eight proteins were expressed. In this group, tatB was overexpressed. A reduction in thioredoxin peroxidase (bacterioferritin co-migratory protein (bcp)) was observed in ulcer vs. gastritis and cancer vs. ulcer. Conclusion: Our study suggested three discrete protein signatures, hypA, tatB, and bcp, with differential expression in gastritis, ulcer, and cancer. Protein expression profiles of H. pylori isolated from patients with these gastric diseases will help to understand the virulence and pathogenesis of H. pylori.

Management of Helicobacter pylori infection: the Maastricht VI/Florence consensus report

Helicobacter pyloriInfection is formally recognised as an infectious disease, an entity that is now included in the International Classification of Diseases 11th Revision. This in principle leads to the recommendation that all infected patients should receive treatment. In the context of the wide clinical spectrum associated with Helicobacter pylori gastritis, specific issues persist and require regular updates for optimised management.The identification of distinct clinical scenarios, proper testing and adoption of effective strategies for prevention of gastric cancer and other complications are addressed. H. pylori treatment is challenged by the continuously rising antibiotic resistance and demands for susceptibility testing with consideration of novel molecular technologies and careful selection of first line and rescue therapies. The role of H. pylori and antibiotic therapies and their impact on the gut microbiota are also considered.Progress made in the management of H. pylori infection is covered in the present sixth edition of the Maastricht/Florence 2021 Consensus Report, key aspects related to the clinical role of H. pylori infection were re-evaluated and updated. Forty-one experts from 29 countries representing a global community, examined the new data related to H. pylori infection in five working groups: (1) indications/associations, (2) diagnosis, (3) treatment, (4) prevention/gastric cancer and (5) H. pylori and the gut microbiota. The results of the individual working groups were presented for a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in various clinical fields.

Helicobacter Pylori-Induced Gastric Infections: From Pathogenesis to Novel Therapeutic Approaches Using Silver Nanoparticles

Helicobacter pylori is the first formally recognized bacterial carcinogen and the most important single digestive pathogen responsible for the induction of gastroduodenal diseases such as gastritis, peptic ulcer, and, finally, gastric neoplasia. The recently reported high rates of antimicrobial drug resistance hamper the current therapies of H. pylori, with therapeutic failure reaching up to 40% of patients. In this context, new treatment options and strategies are urgently needed, but the successful development of these new therapeutic tools is conditioned by the understanding of the high adaptability of H. pylori to the gastric acidic environment and the complex pathogenic mechanism. Due to several advantages, including good antibacterial efficiency, possible targeted delivery, and long tissular persistence, silver nanoparticles (AgNPs) offer the opportunity of exploring new strategies to improve the H. pylori therapy. A new paradigm in the therapy of H. pylori gastric infections using AgNPs has the potential to overcome the current medical limitations imposed by the H. pylori drug resistance, which is reported for most of the current organic antibiotics employed in the classical therapies. This manuscript provides an extensive overview of the pathology of H. pylori-induced gastritis, gastric cancer, and extradigestive diseases and highlights the possible benefits and limitations of employing AgNPs in the therapeutic strategies against H. pylori infections.

Rapamycin Attenuates Anxiety and Depressive Behavior Induced by Helicobacter pylori in Association with Reduced Circulating Levels of Ghrelin

Background. Helicobacter pylori (H. pylori) infection is closely associated with depression and development of neuroinflammation. The aim of this study is to explore the relationship between H. pylori, depression, and circulating levels of ghrelin. Methods. Mice were randomly divided into three groups: healthy control group (gavaged sterile saline and injected with saline, $n=8$ ); H. pylori+saline group (gavaged H. pylori and injected with saline, $n=8$ ); and H. pylori+rapa group (gavaged H. pylori and injected with rapamycin, $n=8$ ). Open field test (OFT), sucrose preference test (SPT), forced swim test (FST), and tail suspension test (TST) were used for anxiety and depressive behavior test. Western blotting was utilized to assess mTOR, p-mTOR, and GSMD expression, and serum ghrelin levels were estimated using ELISA. Results. In the OFT, the control mice moved more and exhibited a increase in crossing number relative to the H. pylori+saline mice (all $P<0.05$ ). Increased quantity of fecal boli can be indicative of increased anxiety and emotionality of the subject animal. H. pylori+saline mice exhibited an increase in fecal boli when compared to control mice and H. pylori+rapa mice ( $P<0.05$ ). H. pylori infected mice decreasing the expression of ghrelin. The protein levels of p-mTOR/mTOR in the gastric antrum mTOR signaling activation and low-level ghrelin in H. pylori-infect mice compared to those in control mice (all P <0.001). Compared with single H. pylori infection, mTOR inhibitors increased the ghrelin secretion of H. pylori infection to a certain extent ( $P<0.05$ ). The protein levels of GSDMD expression significantly increase in hippocampus of H. pylori-infected mice ( $P<0.001$ ). Rapamycin treatment inhibited expression of GSDMD in H. pylori-infected mice ( $P<0.05$ ). Conclusions. H. pylori infection is associated with increased expression of mTOR and decreased circulating levels of ghrelin. Elevated pyroptosis in the brain and anxiety- and depressed-like behaviors occur when ghrelin levels are suppressed.

Relationship between Helicobacter pylori infection and white matter lesions in patients with migraine

Background/aim

White matter lesions (WML) are more frequently observed in migraine patients than in the average population. Associations between Helicobacter pylori (H. pylori) infection and different extraintestinal pathologies have been identified. Here, we aimed to investigate the association between H. pylori infection and WML in patients diagnosed with episodic migraine.

Materials and methods

A retrospective study was conducted with 526 subjects with a diagnosis of episodic migraine. Hyperintensity of WML had been previously evaluated in these patients with brain magnetic resonance imaging (MRI) examinations. Previous endoscopic gastric biopsy histopathological examination of the same patients and reports on H. pylori findings were recorded. The demographic characteristics of the patients, such as age, gender and chronic systemic diseases such as hypertension and diabetes mellitus (DM) were recorded. Statistical evaluation was made.

Results

Evaluation was made among 526 migraine patients who met the inclusion criteria, comprising 397 (75.5%) females and 129 (24.5%) males with a mean age of 45.57 ± 13.46 years (range, 18–69 years). WML was detected on brain MRI in 178 (33.8%) patients who were also positive for H. pylori (p <  0.05). Subjects who are H. pylori-positive with migraine, WML were observed at a 2.5-fold higher incidence on brain MRI (odds ratio: 2.562, 95% CI 1.784–3.680). WML was found to be more significant in patients with hypertension and migraine than those without (p <  0.001). Older age was also found to be associated with WML (OR = 1.07, 95% CI: 0.01–0.04, p <  0.001). The age (p <  0.001), H. pylori (p <  0.001), hypertension (p <  0.001), and hypertension + DM (p <  0.05), had significant associations in predicting WML according to the multivariate logistic regression analysis. The presence of hypertension had a higher odds ratio value than the other variables.

Conclusion

It was concluded that H. pylori infection, as a chronic infection, can be considered a risk factor in developing WML in subjects with migraine.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02715-0.

The Effects of Vitamins and Micronutrients on Helicobacter pylori Pathogenicity, Survival, and Eradication: A Crosstalk between Micronutrients and Immune System

Helicobacter pylori as a class I carcinogen is correlated with a variety of severe gastroduodenal diseases; therefore, H. pylori eradication has become a priority to prevent gastric carcinogenesis. However, due to the emergence and spread of multidrug and single drug resistance mechanisms in H. pylori, as well as serious side effects of currently used antibiotic interventions, achieving successful H. pylori eradication has become exceedingly difficult. Recent studies expressed the intention of seeking novel strategies to improve H. pylori management and reduce the risk of H. pylori-associated intestinal and extragastrointestinal disorders. For which, vitamin supplementation has been demonstrated in many studies to have a tight interaction with H. pylori infection, either directly through the regulation of the host inflammatory pathways or indirectly by promoting the host immune response. On the other hand, H. pylori infection is reported to result in micronutrient malabsorption or deficiency. Furthermore, serum levels of particular micronutrients, especially vitamin D, are inversely correlated to the risk of H. pylori infection and eradication failure. Accordingly, vitamin supplementation might increase the efficiency of H. pylori eradication and reduce the risk of drug-related adverse effects. Therefore, this review aims at highlighting the regulatory role of micronutrients in H. pylori-induced host immune response and their potential capacity, as intrinsic antioxidants, for reducing oxidative stress and inflammation. We also discuss the uncovered mechanisms underlying the molecular and serological interactions between micronutrients and H. pylori infection to present a perspective for innovative in vitro investigations, as well as novel clinical implications.

Effect of Helicobacter pylori-Associated Chronic Gastritis on Autonomous Activity and Sleep Quality in Mice

Many reports have shown that patients with Hp-associated chronic gastritis exhibit anxiety and poor sleep quality. However, less is known about the effects and specific manifestations of Hp-associated chronic gastritis on autonomous activity and sleep quality in animals. Here, we investigated the effect of Helicobacter pylori (Hp)-associated chronic gastritis on autonomous activity and sleep quality in mice. To do this, a Hp-associated chronic gastritis mouse model was first established, then analyzed for autonomous activity, relative to controls, for 15 min using an autonomous activity tester. Next, sleep quality of mice was detected by sodium pentobarbital-induced sleep experiment and results compared between groups. The results showed that male mice in the model group exhibited higher activity counts but lower forelimb lift counts, relative to those in the control group, although there were no significant differences (all p &gt; .05). Conversely, female mice in the model group recorded lower activity counts, albeit at no significant difference (p &gt; .05), and significantly lower counts of forelimb lift (p &lt; .05), relative to those in the control group. Notably, male mice in the model group had longer sleep latency and shorter sleep duration than those in the control group, albeit at no significant differences (all p &gt; .05). On the other hand, female mice in the model group recorded significantly longer sleep latency as well as shorter sleep duration compared to those in the control group (all p &lt; .01). We conclude that Hp-associated chronic gastritis exerts certain effects on autonomous activity and sleep quality of mice in a gender-dependent manner. Notably, female mice with Hp-associated chronic gastritis had lower activity and forelimb lift counts, as well as prolonged sleep latency, and shortened sleep duration. These effects were all statistically significant except for activity counts.

Are We What We Eat? Impact of Diet on the Gut-Brain Axis in Parkinson's Disease

Parkinson’s disease is characterized by motor and non-motor symptoms, such as defects in the gut function, which may occur before the motor symptoms. To date, there are therapies that can improve these symptoms, but there is no cure to avoid the development or exacerbation of this disorder. Dysbiosis of gut microbiota could have a crucial role in the gut–brain axis, which is a bidirectional communication between the central nervous system and the enteric nervous system. Diet can affect the microbiota composition, impacting gut–brain axis functionality. Gut microbiome restoration through probiotics, prebiotics, synbiotics or other dietary means could have the potential to slow PD progression. In this review, we will discuss the influence of diet on the bidirectional communication between gut and brain, thus supporting the hypothesis that this disorder could begin in the gut. We also focus on how food-based therapies might then have an influence on PD and could ameliorate non-motor as well as motor symptoms.

Risk of Psoriasis in Postgastrectomy Gastric Cancer Survivors: A Nationwide Population-Based Cohort Study

Background

Although patients with psoriasis have an increased risk of cancers, little is known about the risk of psoriasis in cancer patients.

Objective

We aimed to comparatively analyze the incidence and risk factors of psoriasis in gastric cancer patients who underwent gastrectomy and in the general population.

Methods

A nationwide retrospective cohort of 52,608 gastric cancer survivors (2007~2015) was compared to 123,438 matched controls from the general population to estimate the incidence and hazard ratio (HR) of new-onset psoriasis. We also calculated the HRs for psoriasis according to adjuvant cancer treatment, obesity, and vitamin B₁₂ supplementation in gastric cancer survivors.

Results

During a mean follow-up of 6.85 years, 645 of the 52,608 gastric cancer patients developed psoriasis, while 1,806 in the 123,438 matched control group developed psoriasis. Gastric cancer patients had a decreased risk of psoriasis (HR, 0.86; 95% confidence interval, 0.79~0.94), especially those who underwent subtotal gastrectomy. We found that vitamin B₁₂ supplementation for more than 3 years had an additive effect on decreasing the risk of psoriasis in gastric cancer patients who underwent subtotal gastrectomy. Total gastrectomy, radio/chemotherapy, and obesity did not affect the risk of psoriasis in gastric cancer survivors.

Conclusion

The incidence of psoriasis is slightly lower in gastric cancer survivors than in the general population. Our results suggest that the development of psoriasis may be reduced by removing the source of systemic inflammation caused by Helicobacter pylori infection through subtotal gastrectomy in gastric cancer survivors.

Association between microbiological risk factors and neurodegenerative disorders: An umbrella review of systematic reviews and meta-analyses

The role of microbiological factors in the development of neurodegenerative diseases is attracting increasing attention, while the relationship remains debated. This study aimed to comprehensively summarize and evaluate the associations between microbiological factors and the risk of neurodegenerative disorders with an umbrella review. PubMed, Embase, and the Cochrane library were used to search for papers from the earliest to March 2021 for identifying meta-analyses and systematic reviews that examined associations between microbiological factors and neurodegenerative diseases. AMSTAR2 tool was employed to evaluate the methodical quality of systematic reviews and meta-analyses. The effect size and 95% confidence interval (95% CI) were recalculated with a random effect model after the overlap was recognized by the corrected covered area (CCA) method. The heterogeneity of each meta-analysis was measured by the I ² statistic and 95% prediction interval (95% PI). Additionally, publication bias and the quality of evidence were evaluated for all 37 unique associations. Only 4 associations had above the medium level of evidence, and the rest associations presented a low level of evidence. Among them, helicobacter pylori (HP), infection, and bacteria are associated with Parkinson's disease (PD), and the other one verifies that periodontal disease is a risk factor for all types of dementia. Following the evidence of our study, eradication of HP and aggressive treatment of periodontitis are beneficial for the prevention of PD and dementia, respectively. This umbrella review provides comprehensive quality-grade evidence on the relationship between microbial factors and neurodegenerative disease. Regardless of much evidence linking microbial factors to neurodegenerative diseases, these associations are not necessarily causal, and the evidence level is generally low. Thus, more effective studies are required.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/#searchadvanced, PROSPERO, identifier: CRD42021239512.

Gastrointestinal Changes and Alzheimer's Disease

BACKGROUND

There is a well-described mechanism of communication between the brain and gastrointestinal system in which both organs influence the function of the other. This bi-directional communication suggests that disease in either organ may affect function in the other.

OBJECTIVE

To assess whether the evidence supports gastrointestinal system inflammatory or degenerative pathophysiology as a characteristic of Alzheimer's disease (AD).

METHODS

A review of both rodent and human studies implicating gastrointestinal changes in AD was performed.

RESULTS

Numerous studies indicate that AD changes are not unique to the brain but also occur at various levels of the gastrointestinal tract involving both immune and neuronal changes. In addition, it appears that numerous conditions and diseases affecting regions of the tract may communicate to the brain to influence disease.

CONCLUSION

Gastrointestinal changes represent an overlooked aspect of AD, representing a more system influence of this disease.

Influence of gut microbiota on eye diseases: an overview

The microbiota is a dynamic ecosystem that plays a major role in the host health. Numerous studies have reported that alterations in the intestinal microbiota (dysbiosis) may contribute to the pathogenesis of various common diseases such as diabetes, neuropsychiatric diseases, and cancer. However, emerging findings also suggest the existence of a gut-eye axis, wherein gut dysbiosis may be a crucial factor influencing the onset and progression of multiple ocular diseases, including uveitis, dry eye, macular degeneration, and glaucoma. Currently, supplementation with pre- and probiotics appears is the most feasible and cost-effective approach to restore the gut microbiota to a eubiotic state and prevent eye pathologies. In this review, we discuss the current knowledge on how gut microbiota may be linked to the pathogenesis of common eye diseases, providing therapeutic perspectives for future translational investigations within this promising research field.

Helicobacter pylori infection and risk for developing dementia: an evidence-based meta-analysis of case-control and cohort studies

BACKGROUND

Infection with multiple pathogens may play a key role in the pathogenesis of dementia. Whether Helicobacter pylori (H. pylori) infection is associated causally with dementia is controversial.

OBJECTIVE

We conduct a meta-analysis of case-control and cohort studies on the association between H. pylori infection and the risk for all-cause and Alzheimer's disease (AD) dementia.

METHODS

Two independent reviewers searched the PubMed, Cochrane Library, and Embase databases with English language restrictions from the date of conception to September 18, 2020. The primary analysis was as follows: the exposure variable was H. pylori infection, and the outcome was incident all-cause and AD dementia. Pooled odds ratios (OR), relative risk (RR), and corresponding 95% confidence intervals (CI) were obtained using the fixed-or random-effect model. Forest plots were generated to summarize the results.

RESULTS

Ten studies involving 96,561 participants were included in the meta-analysis: 5 case-control studies and 5 cohort studies. The overall pooled cohort studies showed a significant positive association between H. pylori infection and all-cause dementia with pooled RR of 1.36 (95% CI, 1.11-1.67). There was no association between H. pylori infection and risk for developing AD: RR of 1.33 (95% CI, 0.86-2.05) in cohort studies, and OR of 1.72 (95% CI, 0.97-3.04) in case-control studies. Significant heterogeneity was showed in each comparison group.

CONCLUSION

This meta-analysis supports a positive association between H. pylori infection and the risk of all-cause dementia, but not AD dementia. Due to the interference of confounding factors, randomized controlled trials are needed to prove their causality.

Helicobacter pylori Infection and Extragastric Diseases-A Focus on the Central Nervous System

Helicobacter pylori (H. pylori) is most known to cause a wide spectrum of gastrointestinal impairments; however, an increasing number of studies indicates that H. pylori infection might be involved in numerous extragastric diseases such as neurological, dermatological, hematologic, ocular, cardiovascular, metabolic, hepatobiliary, or even allergic diseases. In this review, we focused on the nervous system and aimed to summarize the findings regarding H. pylori infection and its involvement in the induction/progression of neurological disorders. Neurological impairments induced by H. pylori infection are primarily due to impairments in the gut-brain axis (GBA) and to an altered gut microbiota facilitated by H. pylori colonization. Currently, regarding a potential relationship between Helicobacter infection and neurological disorders, most of the studies are mainly focused on H. pylori.

Modulation of Neuroinflammation by the Gut Microbiota in Prion and Prion-Like Diseases

The process of neuroinflammation contributes to the pathogenic mechanism of many neurodegenerative diseases. The deleterious attributes of neuroinflammation involve aberrant and uncontrolled activation of glia, which can result in damage to proximal brain parenchyma. Failure to distinguish self from non-self, as well as leukocyte reaction to aggregation and accumulation of proteins in the CNS, are the primary mechanisms by which neuroinflammation is initiated. While processes local to the CNS may instigate neurodegenerative disease, the existence or dysregulation of systemic homeostasis can also serve to improve or worsen CNS pathologies, respectively. One fundamental component of systemic homeostasis is the gut microbiota, which communicates with the CNS via microbial metabolite production, the peripheral nervous system, and regulation of tryptophan metabolism. Over the past 10-15 years, research focused on the microbiota-gut-brain axis has culminated in the discovery that dysbiosis, or an imbalance between commensal and pathogenic gut bacteria, can promote CNS pathologies. Conversely, a properly regulated and well-balanced microbiome supports CNS homeostasis and reduces the incidence and extent of pathogenic neuroinflammation. This review will discuss the role of the gut microbiota in exacerbating or alleviating neuroinflammation in neurodegenerative diseases, and potential microbiota-based therapeutic approaches to reduce pathology in diseased states.

The trimebutine effect on Helicobacter pylori-related gastrointestinal tract and brain disorders: A hypothesis

The localization of bacterial components and/or metabolites in the central nervous system may elicit neuroinflammation and/or neurodegeneration. Helicobacter pylori (a non-commensal symbiotic gastrointestinal pathogen) infection and its related metabolic syndrome have been implicated in the pathogenesis of gastrointestinal tract and central nervous system disorders, thus medications affecting the nervous system - gastrointestinal tract may shape the potential of Helicobacter pylori infection to trigger these pathologies. Helicobacter pylori associated metabolic syndrome, by impairing gut motility and promoting bacterial overgrowth and translocation, might lead to brain pathologies. Trimebutine maleate is a prokinetic drug that hastens gastric emptying, by inducing the release of gastrointestinal agents such as motilin and gastrin. Likewise, it appears to protect against inflammatory signal pathways, involved in inflammatory disorders including brain pathologies. Trimebutine maleate also acts as an antimicrobial agent and exerts opioid agonist effect. This study aimed to investigate a hypothesis regarding the recent advances in exploring the potential role of gastrointestinal tract microbiota dysbiosis-related metabolic syndrome and Helicobacter pylori in the pathogenesis of gastrointestinal tract and brain diseases. We hereby proposed a possible neuroprotective role for trimebutine maleate by altering the dynamics of the gut-brain axis interaction, thus suggesting an additional effect of trimebutine maleate on Helicobacter pylori eradication regimens against these pathologies.

Helicobacter and the Potential Role in Neurological Disorders: There Is More Than Helicobacter pylori

Trillions of symbiotic microbial cells colonize our body, of which the larger part is present in the human gut. These microbes play an essential role in our health and a shift in the microbiome is linked to several diseases. Recent studies also suggest a link between changes in gut microbiota and neurological disorders. Gut microbiota can communicate with the brain via several routes, together called the microbiome–gut–brain axis: the neuronal route, the endocrine route, the metabolic route and the immunological route. Helicobacter is a genus of Gram-negative bacteria colonizing the stomach, intestine and liver. Several papers show the role of H. pylori in the development and progression of neurological disorders, while hardly anything is known about other Helicobacter species and the brain. We recently reported a high prevalence of H. suis in patients with Parkinson’s disease and showed an effect of a gastric H. suis infection on the mouse brain homeostasis. Here, we discuss the potential role of H. suis in neurological disorders and how it may affect the brain via the microbiome–gut–brain axis.

Helicobacter pylori Subdues Cytokine Signaling to Alter Mucosal Inflammation via Hypermethylation of Suppressor of Cytokine Signaling 1 Gene During Gastric Carcinogenesis

Helicobacter pylori infection has been associated with the onset of gastric mucosal inflammation and is known to perturb the balance between T-regulatory (Treg) and T-helper 17 (Th17) cells which causes a spurt of interleukin 17 (IL17) and transforming growth factor-β (TGF-β) from Th17 and Treg cells within the gastric milieu. IL17 instigates a surge of interleukin 6 (IL6) from T-helper 1 (Th1) and T-helper 2 (Th2) cells. Further, H. pylori infection is known to stimulate the atypical DNA methylation in gastric mucosa. However, the precise role of cytokine signaling in induction of epigenetic modifications during gastric carcinogenesis is vaguely understood. In this study, patient samples from were examined using real-time polymerase chain reaction (qPCR), PCR, methylation-specific (MS)-PCR, and enzyme-linked immunosorbent assays. We found that H. pylori infection augments the production of interleukin 10 (IL10), IL6, and TGF-β in the gastric milieu and systemic circulation. Together with the IL6/IL10 mediated hyperactivation of the JAK/STAT pathway, H. pylori infection causes the inactivation of suppressor of cytokine signaling 1 (SOCS1) gene through the hypermethylation of the promoter region. This study signifies that H. pylori-mediated epigenetic silencing of SOCS1 in concert with inflammatory cytokines miffs hyperactivation of the JAK/STAT cascade during gastric carcinogenesis.

Herpes Labialis, Chlamydophila pneumoniae, Helicobacter pylori, and Cytomegalovirus Infections and Risk of Dementia: The Framingham Heart Study

BACKGROUND

An association between chronic infectious diseases and development of dementia has been suspected for decades, based on the finding of pathogens in postmortem brain tissue and on serological evidence. However, questions remain regarding confounders, reverse causality, and how accurate, reproducible and generalizable those findings are.

OBJECTIVE

Investigate whether exposure to Herpes simplex (manifested as herpes labialis), Chlamydophila pneumoniae (C. pneumoniae), Helicobacter pylori (H. pylori), and cytomegalovirus (CMV) modifies the risk of dementia in a populational cohort.

METHODS

Questionnaires regarding incidence of herpes infections were administered to Original Framingham Study participants (n = 2,632). Serologies for C. pneumoniae, H. pylori, and CMV were obtained in Original (n = 2,351) and Offspring cohort (n = 3,687) participants. Participants are under continuous dementia surveillance. Brain MRI and neuropsychological batteries were administered to Offspring participants from 1999-2005. The association between each infection and incident dementia was tested with Cox models. Linear models were used to investigate associations between MRI or neuropsychological parameters and serologies.

RESULTS

There was no association between infection serologies and dementia incidence, total brain volume, and white matter hyperintensities. Herpes labialis was associated with reduced 10-year dementia risk (HR 0.66, CI 0.46-0.97), but not for the duration of follow-up. H. pylori antibodies were associated with worse global cognition (β -0.14, CI -0.22, -0.05).

CONCLUSION

We found no association between measures of chronic infection and incident dementia, except for a reduction in 10-year dementia risk for patients with herpes labialis. This unexpected result requires confirmation and further characterization, concerning antiviral treatment effects and capture of episodes.

Broader Insights into Understanding Tumor Necrosis Factor and Neurodegenerative Disease Pathogenesis Infer New Therapeutic Approaches

Proinflammatory cytokines such as tumor necrosis factor (TNF), with its now appreciated key roles in neurophysiology as well as neuropathophysiology, are sufficiently well-documented to be useful tools for enquiry into the natural history of neurodegenerative diseases. We review the broader literature on TNF to rationalize why abruptly-acquired neurodegenerative states do not exhibit the remorseless clinical progression seen in those states with gradual onsets. We propose that the three typically non-worsening neurodegenerative syndromes, post-stroke, post-traumatic brain injury (TBI), and post cardiac arrest, usually become and remain static because of excess cerebral TNF induced by the initial dramatic peak keeping microglia chronically activated through an autocrine loop of microglial activation through excess cerebral TNF. The existence of this autocrine loop rationalizes post-damage repair with perispinal etanercept and proposes a treatment for cerebral aspects of COVID-19 chronicity. Another insufficiently considered aspect of cerebral proinflammatory cytokines is the fitness of the endogenous cerebral anti-TNF system provided by norepinephrine (NE), generated and distributed throughout the brain from the locus coeruleus (LC). We propose that an intact LC, and therefore an intact NE-mediated endogenous anti-cerebral TNF system, plus the DAMP (damage or danger-associated molecular pattern) input having diminished, is what allows post-stroke, post-TBI, and post cardiac arrest patients a strong long-term survival advantage over Alzheimer's disease and Parkinson's disease sufferers. In contrast, Alzheimer's disease and Parkinson's disease patients remorselessly worsen, being handicapped by sustained, accumulating, DAMP and PAMP (pathogen-associated molecular patterns) input, as well as loss of the LC-origin, NE-mediated, endogenous anti-cerebral TNF system. Adrenergic receptor agonists may counter this.

Extra-Gastric Manifestations of Helicobacter pylori Infection

Helicobacter Pylori (H. pylori) is a Gram-negative flagellated microorganism that has been extensively studied since its first isolation due to its widespread diffusion and association with numerous diseases. While the bacterium is proved to be a causative factor for a number of gastric diseases such as gastritis, gastric adenocarcinoma, and MALT-lymphoma, its role at other gastrointestinal levels and in other systems is being thoroughly studied. In this article, we reviewed the latest published clinical and laboratory studies that investigated associations of H. pylori with hematologic diseases such as Vitamin B12- and iron-deficiency anemia, primary immune thrombocytopenia, and with a number of dermatologic and ophthalmic diseases. In addition, the putative role of the bacterium in inflammatory bowel diseases, esophageal disorders, metabolic, diseases, neurologic diseases and allergy were outlined.

Polymannuronic acid prevents dopaminergic neuronal loss via brain-gut-microbiota axis in Parkinson's disease model

The study aims to investigate the potentially neuroprotective effects and underlying mechanisms for brown seaweed polysaccharide of polymannuronic acid (PM) against Parkinson's disease (PD) pathogenesis. PD model mice were pretreated with PM via oral gavage once per day for 4 weeks and the preventative effects of PM against neuronal loss together with its modulation on brain-gut-microbiota axis were systematically explored. The results showed PM administration improved motor functions by preventing dopaminergic neuronal loss in the substantia nigra pars compacta (SNpc) and enhanced contents of striatal homovanillic acid (HVA), serotonin (5-HT), 5-hydroxyindole acetic acid (5-HIAA) and γ-aminobutyric acid (GABA) in PD mice. PM significantly alleviated inflammation in gut, brain and systemic circulation as shown by reduced levels or expressions of pro-inflammatory cytokines concurrently and inhibited mitogen-activated protein kinases (MAPK) signaling pathway in mice colon. Meanwhile, PM greatly improved integrity of intestinal barrier and blood brain barrier (BBB) as indicated by increased expressions of tight junction associated proteins in both mice colon and SNpc. Further studies indicated PM treatment resulted in changes of gut microbial compositions, together with great alterations of digestion and metabolism of dietary proteins and fats, which led to surge increase of fecal short chain fatty acids (SCFAs) in the colon of PD mice. In conclusion, pre-administration of PM could provide neuroprotective effects against PD pathogenesis by suppressing inflammation in gut, brain and systemic circulation, and by improving integrity of intestinal barrier and BBB. PM might modulate brain-gut-microbiota axis, at least in part, via gut microbiota derived SCFAs as mediators.

Parkinson's Disease and the Gut: Future Perspectives for Early Diagnosis

Parkinson's disease (PD) is a neurodegenerative disease characterized by progressive degeneration of dopaminergic neurons, and at the cellular level by the formation of Lewy bodies in the central nervous system (CNS). However, the onset of the disease is believed to be localized to peripheral organs, particularly the gastrointestinal tract (GIT) and the olfactory bulb sooner before neuropathological changes occur in the CNS. Patients already in the pre-motor stage of PD suffer from various digestive problems and/or due to significant changes in the composition of the intestinal microbiome in this early stage of the disease. Detailed analyses of patient biopsies and autopsies as well as animal models of neuropathological changes characteristic of PD provided important information on the pathology or treatment of PD symptoms. However, presently is not clarified (i) the specific tissue in the GIT where the pathological processes associated with PD is initiated; (ii) the mechanism by which these processes are disseminated to the CNS or other tissues within the GIT; and (iii) which neuropathological changes could also serve as a reliable diagnostic marker of the premotor stages of PD, or (iv) which type of GIT tissue would be the most appropriate choice for routine examination of patient biopsies.

LRRK2 at the Interface Between Peripheral and Central Immune Function in Parkinson's

It is becoming increasingly accepted that there is an interplay between the peripheral immune response and neuroinflammation in the pathophysiology of Parkinson's disease (PD). Mutations in the leucine-rich-repeat kinase 2 (LRRK2) gene are associated with familial and sporadic cases of PD but are also found in immune-related disorders, such as inflammatory bowel disease (IBD) and leprosy. Furthermore, LRRK2 has been associated with bacterial infections such as Mycobacterium tuberculosis and Salmonella typhimurium. Recent evidence suggests a role of LRRK2 in the regulation of the immune system and modulation of inflammatory responses, at a systemic level, with LRRK2 functionally implicated in both the immune system of the central nervous system (CNS) and the periphery. It has therefore been suggested that peripheral immune signaling may play an important role in the regulation of neurodegeneration in LRRK2 as well as non-LRRK2-associated PD. This review will discuss the current evidence for this hypothesis and will provide compelling rationale for placing LRRK2 at the interface between peripheral immune responses and neuroinflammation.

Association between Helicobacter pylori infection and Guillain-Barré Syndrome: A meta-analysis

BACKGROUND

Helicobacter pylori (H pylori) is a Gram-negative bacterium, considered to trigger autoimmune gastrointestinal disorders. This pathogen has also been linked to the autoimmune sequelae in extra-gastrointestinal diseases and peripheral neuropathies. Guillain-Barré syndrome (GBS) is a serious autoimmune demyelinating disorder of peripheral nerves, usually with a post-infectious onset. About 30% of cases of GBS attributed to by Campylobacter jejuni, so, H pylori, could be also involved. Growing evidence suggests the likely involvement of H pylori infection in the development of GBS. The aim of the current study was to therefore estimate the prevalence of H pylori antibodies in GBS.

METHODS

A search of the literature was performed, using the PUBMED database, until December 2018. Data were extracted from six case-control studies, and a stratification analysis was conducted according to cerebrospinal fluid (CSF) or serum detection material.

RESULTS

Among 29 records found, 6 studies met in the inclusion criteria for the meta-analysis. In the CSF subgroup, 105 participants were involved (40 GBS patients and 65 controls), while the serum subgroup included 325 participants (152 GBS and 173 controls). Data were combined using a fixed-effects model. Anti-H pylori IgG were significantly more prevalent in GBS patients compared to controls, in both CSF (95% CI: 9.66-186.56, OR: 42.45, Pz < .00001) and serum (95% CI: 1.30-4.11, OR: 2.31, Pz: .004) subgroups.

CONCLUSION

The present meta-analysis showed a strong association between GBS and the presence of H pylori antibodies, especially in CSF, thereby suggesting a role of H pylori infection in the pathophysiology of GBS.

Do epigenetic changes caused by commensal microbiota contribute to development of ocular disease? A review of evidence

There is evidence that genetic polymorphisms and environmentally induced epigenetic changes play an important role in modifying disease risk. The commensal microbiota has the ability to affect the cellular environment throughout the body without requiring direct contact; for example, through the generation of a pro-inflammatory state. In this review, we discuss evidence that dysbiosis in intestinal, pharyngeal, oral, and ocular microbiome can lead to epigenetic reprogramming and inflammation making the host more susceptible to ocular disease such as autoimmune uveitis, age-related macular degeneration, and open angle glaucoma. Several mechanisms of action have been proposed to explain how changes to commensal microbiota contribute to these diseases. This is an evolving field that has potentially significant implications in the management of these conditions especially from a public health perspective.

Interventional Influence of the Intestinal Microbiome Through Dietary Intervention and Bowel Cleansing Might Improve Motor Symptoms in Parkinson's Disease

The impact of the gut microbiome is being increasingly appreciated in health and in various chronic diseases, among them neurodegenerative disorders such as Parkinson’s disease (PD). In the pathogenesis of PD, the role of the gut has been previously established. In conjunction with a better understanding of the intestinal microbiome, a link to the misfolding and spread of alpha-synuclein via inflammatory processes within the gut is discussed. In a case-control study, we assessed the gut microbiome of 54 PD patients and 32 healthy controls (HC). Additionally, we tested in this proof-of-concept study whether dietary intervention alone or additional physical colon cleaning may lead to changes of the gut microbiome in PD. 16 PD patients underwent a well-controlled balanced, ovo-lacto vegetarian diet intervention including short fatty acids for 14 days. 10 of those patients received additional treatment with daily fecal enema over 8 days. Stool samples were collected before and after 14 days of intervention. In comparison to HC, we could confirm previously reported PD associated microbiome changes. The UDPRS III significantly improved and the levodopa-equivalent daily dose decreased after vegetarian diet and fecal enema in a one-year follow-up. Additionally, we observed a significant association between the gut microbiome diversity and the UPDRS III and the abundance of Ruminococcaceae. Additionally, the abundance of Clostridiaceae was significantly reduced after enema. Dietary intervention and bowel cleansing may provide an additional non-pharmacologic therapeutic option for PD patients.