Helicobacter pylori infection might have a potential role in hepatocyte ballooning in nonalcoholic fatty liver disease

Association between Helicobacter pylori infection, MASLD, and liver fibrosis in patients with severe obesity: a single-center experience

BACKGROUND AND METHODS

Our study sought to evaluate if an association exists between Helicobacter pylori (H. pylori), metabolic dysfunction- associated steatotic liver disease (MASLD), and liver fibrosis in patients with severe obesity (BMI > 35). Our retrospective study included 584 patients over the age of 18 years with severe obesity, who underwent preoperative liver transient elastography (VCTE), upper endoscopy, blood work, and intra-operative liver biopsy concurrent with bariatric surgery at a single institution from July 2020 to September 2021. Liver fibrosis scores including FIB-4, APRI, NAFLD fibrosis score, BARD score, AST: ALT ratio, and NAFLD activity score (NAS) were calculated from the laboratory results and liver biopsy findings. The presence or absence of H. pylori was determined based on gastric biopsies obtained during upper endoscopy. Other variables collected included age, gender, mean preoperative weight, BMI, and the presence or absence of comorbidities. Student's t-test and non-parametric testing were used for the analysis of continuous variables and Chi-square analysis was used for categorical data.

RESULTS

Of the 584 patients, 14.7% were H. pylori positive and 85.3% were negative. Liver fibrosis scores including FIB-4, APRI, and NAFLD fibrosis scores were significantly higher in the positive group (p < 0.05), but there was no difference in AST: ALT ratio and BARD score. A significantly higher VCTE steatosis and fibrosis scores were noted in the H. pylori-positive group (p < 0.05). Similarly, a significantly higher NAS (NAFLD activity score) on liver biopsies was noted in the positive group, with all the individual components of NAS (steatosis, lobular inflammation, and hepatocyte ballooning) being significantly higher in the positive group (p < 0.05). A significantly higher incidence of fibrosis on liver biopsies was noted in the positive group overall and across all stages of fibrosis (p < 0.05). There were no significant differences between the groups in relation to gender, mean weight, BMI, presence of comorbidities including Diabetes Mellitus, and laboratory values.

CONCLUSION

Our study demonstrates that H. pylori colonization or infection is associated with a higher risk of development of MASLD and progression to fibrosis. Further, population-based studies are needed to corroborate our findings.

Prevalence and risk factors associated with metabolic dysfunction-associated steatohepatitis in patients with Helicobacter pylori infection: A population-based study

BACKGROUND

Helicobacter pylori (H. pylori) is associated with the development of gastrointestinal disorders ranging from gastritis to gastric cancer. The evidence of the association between metabolic dysfunction-associated steatohepatitis (MASH) and H. pylori infection in the literature is scarce. Therefore, we aim to evaluate the risk of developing MASH in patients who have had a diagnosis of H. pylori infection independently of any confounding variables.

AIM

To evaluate the risk of developing MASH in patients who have had a diagnosis of H. pylori infection.

METHODS

This study used a validated multicenter research database of over 360 hospitals across 26 healthcare systems across the United States from 1999 to 2022. Multivariate regression analysis assessed the risk of developing MASH, adjusting for confounders including H. pylori infection, obesity, type 2 diabetes, hypertension, dyslipidemia, and male gender. A two-sided P value < 0.05 was considered as statistically significant, and all statistical analyses were performed using R version 4.0.2 (R Foundation for Statistical Computing, Vienna, Austria, 2008).

RESULTS

A total of 79476132 individuals were screened in the database and 69232620 were selected in the final analysis after accounting for inclusion and exclusion criteria. Smokers (14.30%), patients with hyperlipidemia (70.35%), hypertension (73.86%), diabetes mellitus type 2 (56.46%), and obese patients (58.15%) were more common in patients with MASH compared to control. Using a multivariate regression analysis, the risk of MASH was increased in diabetics [odds ratio (OR): 3.55; 95%CI: 3.48-3.62], obese (OR: 5.93; 95%CI: 5.81-6.04), males (OR: 1.49; 95%CI: 1.46-1.52), individuals with hyperlipidemia (OR: 2.43; 95%CI: 2.38-2.49) and H. pylori infection (OR: 2.51; 95%CI: 2.31-2.73).

CONCLUSION

This is the largest population-based study in the United States illustrating an increased prevalence and odds of developing MASH in patients with H. pylori infection after adjusting for risk factors.

Relationship between Helicobacter pylori infection and risk of metabolic dysfunction-associated steatotic liver disease: An updated meta-analysis

BACKGROUND

Recent observational studies examining the association between Helicobacter pylori infection and the risk of metabolic dysfunction-associated steatotic liver disease (MASLD) have reported conflicting results. We performed a meta-analysis to quantify the magnitude of the association between H. pylori infection and the risk of MASLD.

METHODS

We systematically searched three large electronic databases to identify eligible observational studies (published up to 30 November 2023) in which liver biopsy, imaging methods or blood-based biomarkers/scores were used for diagnosing MASLD. Data from selected studies were extracted, and meta-analysis was performed using common and random-effects modelling. Statistical heterogeneity among published studies, subgroup analyses, meta-regression analyses and publication bias were assessed.

RESULTS

A total of 28 observational studies (24 cross-sectional and 4 longitudinal studies) were identified, including 231 291 middle-aged individuals of predominantly Asian ethnicity (~95%). Meta-analysis of cross-sectional studies showed that H. pylori infection was significantly associated with a small increase in the risk of prevalent MASLD (n = 24 studies; random-effects odds ratio 1.11, 95% CI 1.05-1.18; I2 = 63%). Meta-analysis of data from longitudinal studies showed that H. pylori infection was significantly associated with an increased risk of developing incident MASLD over a mean 5-year follow-up (n = 4 studies; random-effects odds ratio 1.20, 95%CI 1.08-1.33; I2 = 44%). Sensitivity analyses did not modify these results. The funnel plot did not reveal any significant publication bias.

CONCLUSIONS

H. pylori infection is associated with a mildly increased risk of prevalent and incident MASLD. Further well-designed prospective and mechanistic studies are required to better decipher the complex link between H. pylori infection and the risk of MASLD.

An update: is there a relationship between H. pylori infection and nonalcoholic fatty liver disease? why is this subject of interest?

Helicobacter pylori (H. pylori) infection is thought to impact various extragastric diseases, including nonalcoholic fatty liver disease (NAFLD), the most common chronic liver disease. Meanwhile, the pathogenesis of NAFLD needs further research, and effective treatment for this disease remains elusive. In this mini-review, we enumerate and ponder on the evidence demonstrating an association between H. pylori infection and NAFLD. Primarily, we delve into high-quality meta-analyses and clinical randomized controlled trials focusing on the association studies between the two. We also discuss clinical studies that present opposite conclusions. In addition, we propose a mechanism through which H. pylori infection aggravates NAFLD: inflammatory cytokines and adipocytokines, insulin resistance, lipid metabolism, intestinal barrier and microbiota, H. pylori outer membrane vesicles and H. pylori-infected cell-extracellular vesicles. This mini-review aims to further explore NAFLD pathogenesis and extragastric disease mechanisms caused by H. pylori infection.

Helicobacter pylori-derived outer membrane vesicles suppress liver autophagy: A novel mechanism for H. pylori-mediated hepatic disorder

BACKGROUND

Helicobacter pylori outer membrane vesicles (OMVs) are nano-sized structures, which have been recently suggested to play a crucial role in H. pylori pathogenesis. There are growing evidence indicating the relationship of H. pylori infection with extra-gastroduodenal diseases, especially liver-related disorders. This study was aimed to investigate the effects of H. pylori-derived OMVs on autophagy in hepatic stellate cells (HSCs).

MATERIAL AND METHODS

A selection of five clinical strains of H. pylori with different virulence genotypes were included. The OMVs were isolated by ultracentrifugation and characterized by scanning electron microscopy (SEM) and dynamic light scattering (DLS). The protein concentration of OMVs was measured by BCA assay. MTT assay was used to determine the viability of LX-2 cells (human HSCs) treated with OMVs. The expression level of MTOR, AKT, PI3K, BECN1, ATG16 and LC3B genes was assessed in OMVs-treated LX-2 cells using quantitative real-time PCR. Moreover, immunocytochemistry was performed to evaluate the protein expression of MTOR and LC3B autophagy markers.

RESULTS

H. pylori strains produced round shape nano-vesicles ranging from 50 to 500 nm. Treatment of HSCs with H. pylori-derived OMVs at concentration of 10 μg/mL for 24 h significantly elevated the expression of autophagy inhibitory markers (PI3K, AKT, and MTOR) and suppressed the mRNA expression level of autophagy core proteins (BECN1, ATG16 and LC3B). Immunocytochemistry also presented a substantial reduction in the concentration of LC3B autophagy core protein, and a marked elevation in the amount of MTOR autophagy inhibitory protein.

CONCLUSION

This study revealed that H. pylori-derived OMVs could potentially suppress autophagy flux in HSCs as a novel mechanism for H. pylori-mediated liver autophagy impairment and liver disease development. Further studies are required to elucidate the exact role of OMV-carried contents in liver autophagy, and liver-associated disorders.

Helicobacter pylori infection increases the risk of nonalcoholic fatty liver disease: Possible relationship from an updated meta-analysis

BACKGROUND

The relationship between Helicobacter pylori (H pylori) infection and nonalcoholic fatty liver disease (NAFLD) has long been debated. Although it has been investigated in many observational studies, the results remain controversial. Therefore, we performed an updated meta-analysis to assess the association between H pylori infection and risk of NAFLD by collecting relevant articles.

METHODS

Literature collections were conducted by searching PubMed, EMBASE, Web of Science and Cochrane Library databases. Pooled odds ratios with corresponding 95% confidence intervals were calculated to estimate the strength of the link between H pylori infection and NAFLD using Stata 12.0 software.

RESULTS

28 studies with 68,047 cases of NAFLD patients and 134,866 controls were finally included in the meta-analysis. Overall, The results suggested a 27.5% increased risk of developing NAFLD in patients with H pylori infection (odds ratios 1.275 95% confidence intervals 1.179-1.379), although significant heterogeneity was observed. There is no significant publication bias observed based on the funnel plot and Begg test. Subgroup analysis revealed that variables of the study design, study region, publication year, and the method of diagnosing H pylori and NAFLD all contribute to the high heterogeneity, while the positive correlation was seen in all subgroup analysis.

CONCLUSION

This meta-analysis disclosed 1.275-fold increased risk of the occurrence and development of NAFLD in H pylori (+) group compared with the H pylori (-) group, indicating that H pylori is a serious risk factor in patients susceptible to NAFLD.

The possible role of Helicobacter pylori in liver diseases

According to previous studies, Helicobacter pylori infection is associated with liver disease. In order to better understand the risk of acquiring various liver diseases, we reviewed current knowledge on the impact of H. pylori on the onset, intensification, and progression of various liver diseases caused by the infection of H. pylori. It has been estimated that between 50 and 90% of people worldwide have been infected with H. pylori. The bacterium is mostly responsible for inflamed gastric mucosa, ulcers, and cancers associated with the gastric mucosa. Through the active antioxidant system in H. pylori, the bacteria can neutralize free radicals by synthesizing VacA, a toxin that causes cell damage and apoptosis. Furthermore, there is a possibility that CagA genes may play a role in cancer development. People who have been infected with H. pylori are likely to develop lesions in the skin, the circulation system, and the pancreas. Moreover, transferring blood from the stomach may allow H. pylori to colonize the liver. The bacterium worsened liver function during autoimmune inflammation, toxic injury, chronic HCV infection, chronic HBV infection, and liver cirrhosis. Increasing portal pressure, hyperammonemia, and esophageal varices may be associated with H pylori infection. As a result, it is crucial to diagnose and treat this infection in patients with H. pylori.

Helicobacter pylori infection increases the risk of nonalcoholic fatty liver disease in diabetic population

Background

The effect of Helicobacter pylori (H. pylori) on nonalcoholic fatty liver disease (NAFLD) in the population is still controversial. Diabetes and NAFLD are both metabolically related diseases, and no studies have classified the population to study the effect of H. pylori infection on NAFLD in diabetics.

Methods

A population of people who were examined in the Taizhou Hospital Health Examination Center from 2017 to 2022 was included, and hematological indicators, body parameters, ultrasound data, and H. pylori detection by urea nitrogen test were collected from patients. All physical examination populations were divided into diabetic and non-diabetic populations.

Results

After multivariate logistic regression, H. pylori infection remained an independent risk factor for NAFLD in diabetics, but it had no significant effect on NAFLD in non-diabetic population. Additionally, there was a nonlinear relationship between glycosylated hemoglobin and H. pylori infection in diabetic population. Moreover, the incidence of NAFLD in diabetics increased with persistent H. pylori infection.

Conclusion

In the diabetic population, H. pylori infection does increase the risk of developing NAFLD. Glycemic control and eradication of H. pylori infection may have positive implications for reducing the incidence of NAFLD in diabetic population.

Impact of nonalcoholic fatty liver disease-related metabolic state on depression

Nonalcoholic fatty liver disease (NAFLD), also recently referred as metabolic (dysfunction)-associated fatty liver disease (MAFLD), is characterized by hepatocyte steatosis in the setting of metabolic risk conditions and in the absence of an underlying precursor, for instance alcohol consumption, hepatotropic viruses and hepatotoxic drugs. A possible association between NAFLD and depression has been proposed, owing to intersecting pathophysiological pathways. This narrative review aimed to summarize the current evidence that illustrate the potential pathophysiological and clinical linkage between NAFLD-related metabolic state and depression. Prefrontal cortex lesions are suggested to be a consequence of liver steatosis-associated systematic hyperinflammatory state, a phenomenon also occurring in depression. In addition, depressive symptoms are present in neurotransmitter imbalances. These abnormalities seem to be correlated with NAFLD/MAFLD, in terms of insulin resistance (IR), ammonia and gut dysbiosis' impact on serotonin, dopamine, noradrenaline levels and gamma aminobutyric acid receptors. Furthermore, reduced levels of nesfatin-1 and copine-6-associated BDNF (brain-derived neurotrophic factor) levels have been considered as a probable link between NAFLD and depression. Regarding NAFLD-related gut dysbiosis, it stimulates mediators including lipopolysaccharides, short-chain fatty acids and bile acids, which play significant role in depression. Finally, western diet and IR, which are mainstay components of NAFLD/MAFLD, are, also, substantiated to affect neurotransmitters in hippocampus and produce neurotoxic lipids that contribute to neurologic dysfunction, and thus trigger emotional disturbances, mainly depressive symptoms.

Relationship of Helicobacter pylori Infection with Nonalcoholic Fatty Liver Disease: A Meta-Analysis

Background and Aims

Helicobacter pylori (H. pylori) and nonalcoholic fatty liver disease (NAFLD) have become increasingly recognized, both of which affect human health globally. The association of H. pylori infection with NAFLD remains unclear.

Methods

PubMed, EMBASE, and Cochrane Library databases were searched. Only a random-effects model was used. Odds ratios (ORs) and risk ratios (RRs) with 95% confidence intervals (CIs) were calculated for the combined estimates of raw data. Adjusted ORs (aORs) and hazard ratios (aHRs) with 95% CIs were calculated for the combined estimates of data adjusted for confounders.

Results

Thirty-four studies with 218573 participants were included. Based on unadjusted data from 26 cross-sectional studies and 3 case-control studies, H. pylori infection was significantly associated with the presence of NAFLD (OR = 1.26, 95% CI = 1.17-1.36, P < 0.001). Based on adjusted data from 15 cross-sectional studies and 1 case-control study, H. pylori infection was significantly associated with the presence of NAFLD (aOR = 1.25, 95% CI = 1.08-1.44, P < 0.001). Compared with control subjects without NAFLD, patients with moderate (OR = 1.67, 95% CI = 1.17-2.39, P = 0.005) and severe (OR = 1.71, 95% CI = 1.30-2.24, P < 0.001) NAFLD, but not those with mild NAFLD (OR = 1.14, 95% CI = 0.9-1.45, P = 0.286), had significantly higher proportions of H. pylori infection. The association of H. pylori infection with the occurrence of NAFLD was statistically significant based on adjusted data from 3 cohort studies (aHR = 1.18, 95% CI = 1.05-1.34, P = 0.007), but not based on unadjusted data from 3 cohort studies (RR = 1.41, 95% CI = 0.80-2.48, P = 0.237).

Conclusion

H. pylori infection is associated with NAFLD, especially moderate and severe NAFLD. The impact of H. pylori eradication on the prevention of NAFLD should be further explored.

The Effects of Helicobacter pylori-Derived Outer Membrane Vesicles on Hepatic Stellate Cell Activation and Liver Fibrosis In Vitro

Introduction

Helicobacter pylori is a prevalent pathogenic bacterium that resides in the human stomach. Outer membrane vesicles (OMVs) are known as nanosized cargos released by H. pylori, which have been proposed to have a key role in disease progression, pathogenesis, and modulation of the immune system. There are multiple evidences for the role of H. pylori in extragastroduodenal illnesses especially liver-related disorders. However, the precise mechanism of H. pylori extragastroduodenal pathogenesis still remains unclear. In the current study, we aimed to determine the impact of H. pylori-isolated OMVs on hepatic stellate cell (HSC) activation and expression of liver fibrosis markers.

Materials and Methods

Five H. pylori clinical strains with different genotype profiles were used. Helicobacter pylori OMVs were isolated using ultracentrifugation and were analyzed by scanning electron microscopy (SEM) and dynamic light scattering (DLS). Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis was applied to determine protein components of H. pylori-derived OMVs. Cell viability of LX-2 human hepatic stellate cell line exposed to OMVs was measured by MTT assay. LX-2 cells were treated with OMVs for 24 h. The gene expression of α-SMA, E-cadherin, vimentin, snail, and β-catenin was analyzed using quantitative real-time PCR. The protein expression of α-SMA, as a well-studied profibrotic marker, was evaluated with immunocytochemistry.

Results

Our results showed that H. pylori strains released round shape nanovesicles ranging from 50 to 500 nm. Totally, 112 various proteins were identified in OMVs by proteomic analysis. The isolated OMVs were negative for both CagA and VacA virulence factors. Treatment of HSCs with H. pylori-derived OMVs significantly increased the expression of fibrosis markers.

Conclusions

In conclusion, the present study demonstrated that H. pylori-derived OMVs could promote HSC activation and induce the expression of hepatic fibrosis markers. Further research is required to elucidate the definite role of H. pylori-derived OMVs in liver fibrosis and liver-associated disorders.

Association between Helicobacter pylori infection and non-alcoholic fatty liver disease for Asian and non-Asian population: A systematic review and meta-analysis

Background

Several studies have revealed a positive correlation between a Helicobacter pylori (HP) infection and the risk of non-alcoholic fatty liver disease (NAFLD). This meta-analysis was conducted to explore further the relationship between HP infection and NAFLD in the Asian and non-Asian populations.

Methods

Relevant studies published from inception to July 22, 2021, in the following databases: PubMed, EMBASE, the Cochrane library, and Web of Science were comprehensively searched. The odds ratio (OR) and hazard ratio (HR) with a 95% confidence interval (95%CI) were pooled by the random-effects model or fixed-effects model. Additionally, subgroup and sensitivity analyses were performed. The funnel plot and the Egger test were used to estimate publication bias.

Results

This meta-analysis included 25 studies involving 107,306 participants. Positive associations between HP infection and NAFLD were found both for the Asian (OR = 1.30, 95% CI: 1.13-1.49, P < 0.01; I 2 = 94.30%, P < 0.01) and non-Asian populations (OR = 1.42, 95% CI: 1.04-1.94, P = 0.03; I 2 = 44.90%, P = 0.09). Moreover, similar results were observed in the Asian female group (OR = 1.31, 95% CI: 1.17-1.46, P < 0.01; I 2 = 46.30%, P = 0.07) but not for the Asian male group. Subgroup analyses for the Asian population showed that there were differences in the association among NAFLD diagnosis methods (P < 0.01) and the study design (P < 0.01). However, subgroup and sensitivity analyses results showed that the association for the non-Asian population was not stable enough.

Conclusions

The data obtained in this systematic review and meta-analysis suggested that an HP infection was associated with an increased risk of NAFLD for Asian and non-Asian populations. However, the association was not found for Asian males. Further studies are required to establish the causal association, especially for the non-Asian population.

Systematic review registration

Identifier: CRD42021266871.

Non-alcoholic fatty liver disease is not independently associated with Helicobacter pylori in a central European screening cohort

BACKGROUND

The association between Helicobacter pylori (Hp) infection and non-alcoholic fatty liver disease (NAFLD) is subject of a contentious debate. Data mainly stem from Asian cohorts whereas European data are scarce. We, therefore, investigated an Austrian colorectal cancer screening cohort for an association between Hp and NAFLD.

METHODS

In total, 5338 consecutive participants undergoing screening colonoscopy at a single center in Austria were evaluated in this cross-sectional study. The primary risk factor was being Hp negative or positive. The primary endpoint was the presence of NAFLD defined by ultrasound (NAFLD; primary endpoint). Uni- and multivariable logistic regression models were fitted to obtain odds ratios (OR) and 95% confidence intervals (95%CI). Finally, this association was analyzed in a subgroup of 1128 patients in whom NAFLD was diagnosed by transient elastography (TE, secondary endpoint).

RESULTS

NAFLD prevalence defined by ultrasound did not differ between Hp positive (48%) and negative patients (45%, P=0.097). Accordingly, in uni- (OR 1.12 95% CI 0.98-1.29; P=0.098) and multivariable analysis adjusting for different risk factors (aOR 0.96 95%CI 0.82-1.13; P=0.601) no independent association was found. On subgroup analysis, NAFLD diagnosed by TE was more prevalent in the Hp positive compared to the Hp negative group (49% vs. 38%, P=0.004) and these patients also had higher steatosis grades. However, after adjustment for risk factors, no independent association between Hp positivity and NAFLD diagnosed by TE (aOR 1.26 95%CI 0.89-1.78; P=0.194) was confirmed.

CONCLUSIONS

In this Central European cohort, Hp-positivity was not associated with the diagnosis of NAFLD. Although Hp positive patients seem to be more likely to have a concomitant NAFLD diagnosis, this association might rather relate to a cardiometabolic risk phenotype than causality.

Helicobacter pylori infection eradication for nonalcoholic fatty liver disease: a randomized controlled trial

Previous studies have suggested that Helicobacter pylori (H. pylori) infection is associated with nonalcoholic fatty liver disease (NAFLD). The purpose of the present study was to investigate the effect of H. pylori eradication treatment on NAFLD patients. Two hundred NAFLD patients who tested positive for H. pylori infection were randomized into the H. pylori eradication treatment group or the control group. Metabolic and inflammatory parameters and FibroScan were measured in all subjects at baseline and 1 year after treatment. At 1 year after treatment, the decrease in metabolic indicators, such as fasting blood glucose, glycosylated haemoglobin, homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides, body mass index and controlled attenuation parameter values, were more obvious in the treatment group. Moreover, the inflammatory indicators white blood count and high-sensitivity C-reactive protein (hs-CRP) and the inflammatory factors interleukin 6 (IL-6) and tumour necrosis factor-α (TNF-α) were also significantly decreased. H. pylori eradication can further reduce the metabolic indices of NAFLD and the degree of liver steatosis. H. pylori infection may participate in the occurrence and development of NAFLD through its influence on inflammatory factors. Thus, checking for the presence of H. pylori infection in patients at risk of NAFLD may be beneficial.

Total Flavonoids from Chimonanthus nitens Oliv. Leaves Ameliorate HFD-Induced NAFLD by Regulating the Gut–Liver Axis in Mice

Non-alcoholic fatty liver disease (NAFLD) is one of the chronic liver diseases with high incidence in the world. This study aimed to investigate whether total flavonoids from Chimonanthus nitens Oliv. leaves (TFC) can ameliorate NAFLD. Herein, a high-fat diet (HFD)-induced NAFLD mice model was established, and TFC was administered orally. The results showed that TFC reduced the body weight and liver index and decreased the serum and hepatic levels of triglyceride (TG) and total cholesterol (TC). TFC significantly reduced the activity of liver functional transaminase. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) decreased by 34.61% and 39.57% in serum and 22.46% and 40.86% in the liver, respectively. TFC regulated the activities of oxidative-stress-related enzymes and upregulated the protein expression of nuclear factor E2-related factor (Nrf2)/heme oxygenase (HO-1) pathway in NAFLD mice, and the activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) in serum were increased by 89.76% and 141.77%, respectively. In addition, TFC reduced the levels of free fatty acids (FFA), endotoxin (ET), and related inflammatory factors in mouse liver tissue and downregulated the expression of proteins associated with inflammatory pathways. After TFC treatment, the levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1β in the liver tissues of NAFLD mice were downregulated by 67.10%, 66.56%, and 61.45%, respectively. Finally, TFC reduced liver fat deposition, oxidative stress, and inflammatory response to repair liver damage and alleviate NAFLD. Further studies showed that TFC regulated the expression of intestinal-barrier-related genes and improved the composition of gut microbiota. Therefore, TFC reduced liver inflammation and restored intestinal homeostasis by regulating the gut–liver axis. Overall, our findings revealed a novel function of TFC as a promising prophylactic for the treatment of NAFLD.

The Microbiota and It’s Correlation With Metabolites in the Gut of Mice With Nonalcoholic Fatty Liver Disease

In recent years, nonalcoholic fatty liver disease (NAFLD) has become the most common liver disease in the world. As an important model animal, the characteristics of gut microbiota alteration in mice with NAFLD have been studied but the changes in metabolite abundance in NAFLD mice and how the gut microbiota affects these intestinal metabolites remain unclear. In this experiment, a mouse model for NAFLD was established by a high-fat diet. The use of 16S rDNA technology showed that while there were no significant changes in the alpha diversity in the cecum of NAFLD mice, the beta diversity changed significantly. The abundance of Blautia, Unidentified-Lachnospiraceae, Romboutsia, Faecalibaculum, and Ileibacterium increased significantly in NAFLD mice, while Allobaculum and Enterorhabdus decreased significantly. Amino acids, lipids, bile acids and nucleotide metabolites were among the 167 significantly different metabolites selected. The metabolic pathways of amino acids, SFAs, and bile acids were significantly enhanced, while the metabolic pathways of PUFAs, vitamins, and nucleotides were significantly inhibited. Through correlation and MIMOSA2 analysis, it is suggested that gut microbiota does not affect the changes of lipids and bile acids but can reduce thiamine, pyridoxine, and promote L-phenylalanine and tyramine production. The findings of this study will help us to better understand the relationship between gut microbiota and metabolites in NAFLD.

Helicobacter pylori infection is not an independent risk factor of non-alcoholic fatty liver disease in China

Background

The role of Helicobacter pylori (H. pylori) infection in the development of non-alcoholic fatty liver disease (NAFLD) remains controversial. The exact relationship requires further investigation. This study aimed to determine the association between them in China.

Methods

A retrospective study was conducted on 71,633 participants who underwent physical examinations. ¹³C urea breath test (¹³C-UBT) was conducted to detect H. pylori infection, and ultrasonography was used to detect NAFLD.

Results

Body mass index (BMI), blood pressure (BP), and triglyceride (TG) levels were higher in participants with H. pylori infection than in those without H. pylori infection. While the levels of high-density lipoprotein cholesterol (HDL-C) for participants with H. pylori infection was lower than without H. pylori infection (P < 0.001). After adjusting for confounding factors (age, sex, BMI, BP, Scr, BUN, LDL-C, HDL-C, triglycerides, FBG and HbA1c), multivariate logistic regression analysis indicated that there was no independent relationship between them (P = 0.574). Subgroup analysis (stratified by sex, age, BMI, hypertension, diabetes and dyslipidemia) showed that H. pylori infection was not included as an independent risk factor for NAFLD. Moreover, the different grades of NAFLD were not related to H. pylori infection.

Conclusions

These results indicate that H. pylori infection is not an independent risk factor for NAFLD in China.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02148-6.

Abnormal transaminase and lipid profiles in coexisting diseases in patients with fatty liver: a population study in Sichuan

Among chronic liver diseases, fatty liver has the highest incidence worldwide. Coexistence of fatty liver and other chronic diseases, such as diabetes, hepatitis B virus (HBV) and Helicobacter pylori (Hp) infection, is common in clinical practice. The present study was conducted to analyze the prevalence and association of coexisting diseases in patients with fatty liver and to investigate how coexisting diseases contribute to abnormal transaminase and lipid profiles. We enrolled participants who were diagnosed with fatty liver via ultrasound in the physical examination center of West China Hospital. Multivariable logistic regression was used to determine the adjusted odds ratios (ORs). We found that 23.6% of patients who underwent physical examinations were diagnosed with fatty liver. These patients had higher risks of metabolic syndrome (MetS), type 2 diabetes mellitus (T2DM), and hypertension and a lower risk of HBV infection. The risks of Hp infection and hyperthyroidism did not statistically differ. When fatty liver coexisted with T2DM, MetS and thyroid dysfunction, it conferred a higher risk of elevated transaminase. Fatty liver was positively correlated with triglycerides, cholesterol and low-density lipoprotein cholesterol (LDL-C) and negatively correlated with HBV; thus, HBV had a neutralizing effect on lipid metabolism when coexisting with fatty liver. In conclusion, patients with fatty liver that coexists with T2DM, MetS and thyroid dysfunction are more prone to elevated transaminase levels. Patients with both fatty liver and HBV may experience a neutralizing effect on their lipid metabolism. Thus, lipid alterations should be monitored in these patients during antiviral treatment for HBV.

Relationship between Helicobacter pylori infection and nonalcoholic fatty liver disease: What should we expect from a meta-analysis?

BACKGROUND

The relationship between Helicobacter pylori (H. pylori) infection and nonalcoholic fatty liver disease (NAFLD) is a matter of debate. Although it has been studied in many observational studies, the results remain controversial. Therefore, we performed a meta-analysis to assess the association between H pylori infection and risk of NAFLD.

METHODS

We searched Pubmed, EMBASE, and Web of Science databases, from inception to September 10, 2020. Odds ratio (OR) and 95% confidence interval (CI) were pooled by random-effects model. The statistical heterogeneity among studies (I2-index), subgroup analyses, regression analyses, sensitivity analysis and the possibility of publication bias were assessed.

RESULTS

A total of seventeen studies involving 91,958 individuals were included in our meta-analysis. Meta-analysis of data from cross-sectional and case-control studies showed that H pylori infection was associated with increased risk of prevalent NAFLD (n = 15; involving 74,561 middle-aged individuals; OR1.38, 95% CI 1.23-1.55, I2 = 86.8%, P < .001). The results of meta-regression implicated that the study type and the case-control ratio impacted the total effect size. Funnel plot did not show significant publication bias. Meta-analysis of data from longitudinal studies showed that H pylori infection was also associated with increased NAFLD incidence (n = 2; involving 17397 individuals; OR 1.21, 95% CI 1.01-1.44, I2 = 6.5%, P = .301).

CONCLUSIONS

The results indicated that a positive association between H pylori infection and the risk of NAFLD. Further studies are required to strengthen the association and clarify the mechanism.

Infections at the nexus of metabolic-associated fatty liver disease

Metabolic-associated fatty liver disease (MAFLD) is a chronic liver disease that affects about a quarter of the world population. MAFLD encompasses different disease stadia ranging from isolated liver steatosis to non-alcoholic steatohepatitis (NASH), fibrosis, cirrhosis and hepatocellular carcinoma. Although MAFLD is considered as the hepatic manifestation of the metabolic syndrome, multiple concomitant disease-potentiating factors can accelerate disease progression. Among these risk factors are diet, lifestyle, genetic traits, intake of steatogenic drugs, male gender and particular infections. Although infections often outweigh the development of fatty liver disease, pre-existing MAFLD could be triggered to progress towards more severe disease stadia. These combined disease cases might be underreported because of the high prevalence of both MAFLD and infectious diseases that can promote or exacerbate fatty liver disease development. In this review, we portray the molecular and cellular mechanisms by which the most relevant viral, bacterial and parasitic infections influence the progression of fatty liver disease and steatohepatitis. We focus in particular on how infectious diseases, including coronavirus disease-19, hepatitis C, acquired immunodeficiency syndrome, peptic ulcer and periodontitis, exacerbate MAFLD. We specifically underscore the synergistic effects of these infections with other MAFLD-promoting factors.

Non-invasive diagnosis of nonalcoholic fatty liver disease: impact of age and other risk factors

BACKGROUND AND OBJECTIVES

Little is known regarding the diagnostic performance of fibrosis scoring systems in the diagnosis of nonalcoholic fatty liver disease (NAFLD). We aimed to determine the risk factors of NAFLD and evaluate the diagnostic performance of noninvasive fibrosis scoring systems.

MATERIALS AND METHODS

The study included consecutive patients presented with dyspepsia from January 2017 to January 2019. Clinicodemographic and laboratory parameters including HOMA-IR were recorded. Anthropometric measurements were performed. NAFLD was diagnosed with ultrasonography. The FIB4, NAFLD, BARD, and Nippon scores were calculated.

RESULTS

Totally, 1008 patients were enrolled. The mean age was 52.3 ± 15 years in the NAFLD group (25.8%) and 36.7 ± 15.7 years in the non-NAFLD group (74.2%). The frequency of NAFLD was 25.8%. Age, body mass index (BMI), diabetes mellitus (DM), platelet count, HbA1c, HDL, ALT, and AST/ALT ratio were independent risk factors for NAFLD. The most sensitive and specific tests in diagnosing NAFLD were HOMA-IR and Nippon score, respectively.

CONCLUSIONS

Age, BMI, DM, HbA1c, platelet count, HDL, ALT, and AST/ALT ratio were independent predictors of NAFLD. The most specific and sensitive predictors of the presence of NAFLD were Nippon score and HOMA-IR value, respectively. The place of fibrosis scores in the diagnosis of NAFLD patients requires further scrutinization.

Associations between Helicobacter pylori with nonalcoholic fatty liver disease and other metabolic conditions in Guatemala

BACKGROUND

Previous studies have suggested an association between Helicobacter pylori (H pylori) and nonalcoholic fatty liver disease (NAFLD). The aim of the current study was to examine the association in Guatemala, a region with elevated prevalences of both H pylori and NAFLD. Associations between H pylori and other metabolic conditions were also examined, as were associations between H hepaticus and H bilis and the metabolic conditions.

MATERIALS & METHODS

The analysis included 424 participants from a cross-sectional study in Guatemala. H pylori seropositivity was defined as positivity for ≥ 4 antigens. Seropositivities for H bilis and H hepaticus were defined as positivity for ≥ 2 antigens. NAFLD was estimated using the Fatty Liver Index and the Hepatic Steatosis Index. Other conditions examined were obesity, central obesity, hypercholesterolemia, low HDL, diabetes and metabolic syndrome (MetSyn). Prevalence odds ratios (POR) and 95% confidence intervals (CIs) were estimated.

RESULTS

No overall associations between H pylori,H hepaticus, or H bilis and NAFLD or related metabolic conditions were found. Seropositivity for H pylori antigens CagA and VacA and H hepaticus antigen HH0713 was each significantly associated with NAFLD, however. In addition, associations were observed between the H pylori antigens HyuA, HP1564, and UreA and specified metabolic conditions.

CONCLUSIONS

While no overall associations between H pylori or Helicobacter species with NAFLD or related conditions were observed, some selected Helicobacter spp. antigens were associated with NAFLD. Further research is warranted to examine whether H. species are associated with any metabolic condition.

Helicobacter pylori Related Diseases and Osteoporotic Fractures (Narrative Review)

Osteoporosis (OP) and osteoporotic fractures (OFs) are common multifactorial and heterogenic disorders of increasing incidence. Helicobacter pylori (H.p.) colonizes the stomach approximately in half of the world's population, causes gastroduodenal diseases and is prevalent in numerous extra-digestive diseases known to be associated with OP/OF. The studies regarding relationship between H.p. infection (HPI) and OP/OFs are inconsistent. The current review summarizes the relevant literature on the potential role of HPI in OP, falls and OFs and highlights the reasons for controversies in the publications. In the first section, after a brief overview of HPI biological features, we analyze the studies evaluating the association of HPI and bone status. The second part includes data on the prevalence of OP/OFs in HPI-induced gastroduodenal diseases (peptic ulcer, chronic/atrophic gastritis and cancer) and the effects of acid-suppressive drugs. In the next section, we discuss the possible contribution of HPI-associated extra-digestive diseases and medications to OP/OF, focusing on conditions affecting both bone homeostasis and predisposing to falls. In the last section, we describe clinical implications of accumulated data on HPI as a co-factor of OP/OF and present a feasible five-step algorithm for OP/OF risk assessment and management in regard to HPI, emphasizing the importance of an integrative (but differentiated) holistic approach. Increased awareness about the consequences of HPI linked to OP/OF can aid early detection and management. Further research on the HPI-OP/OF relationship is needed to close current knowledge gaps and improve clinical management of both OP/OF and HPI-related disorders.

Active Helicobacter pylori Infection is Independently Associated with Nonalcoholic Steatohepatitis in Morbidly Obese Patients

Nonalcoholic fatty liver disease (NAFLD) emerges as an important global burden and Helicobacter pylori infection (Hp-I) has been suggested as a risk factor of NAFLD, although controversy exists. This retrospective study aimed to investigate a potential impact of active Hp-I on NAFLD severity in morbidly obese patients, subjected to bariatric surgery and gastric biopsy for documentation of Hp-I. Of 64 eligible participants, 15 (23.4%) were diagnosed with active Hp-I, showing higher rates of nonalcoholic steatohepatitis (NASH) than those without Hp-I (86.7% vs. 26.5%, respectively; p < 0.001). Concerning histological lesions, steatosis grade (p = 0.027), ballooning (p < 0.001), lobular inflammation (p = 0.003), and fibrosis stage (p < 0.001) were also more severe in Hp-I positive patients. Likewise, liver function tests, insulin resistance, dyslipidemia, and arterial hypertension were significantly higher in Hp-I positive patients. Hp-I was independently positively associated with NASH (beta = 3.27; p = 0.002), severe NASH (beta = 2.37; p = 0.018), and the presence of fibrosis (beta = 3.86; p = 0.001) in a binary regression model, after adjustment for potential confounders. In conclusion, active Hp-Ι was independently associated with NASH and fibrosis, findings offering potential clinical implication.

Relationship Between Helicobacter pylori Infection and Nonalcoholic Fatty Liver Disease (NAFLD) in a Developing Country: A Cross-Sectional Study

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a very common disease that affects 25-30% of the population in western countries. Many studies have observed the importance of H. pylori infection in the development of insulin resistance, non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, and liver fibrosis and cirrhosis. However, the evidence from different studies was controversial. The present study aimed to investigate the relationship between H. pylori infection and NAFLD in a developing country.

PATIENTS AND METHODS

This cross-sectional study included all the attending outpatient clinics at four Major University hospitals and two research and clinical institutes in a developing country in the period between June and October 2019. Patients were assessed for the diagnosis of H. pylori infection as detected by H. pylori antigen in stool; they were also assessed for the diagnosis of NAFLD by ultrasound, fibroscan, and CAP.

RESULTS

The study was conducted on 646 patients; H. pylori infection was found to be present in 538 patients (83.3%). NAFLD (diagnosed by both U/S and Fibroscan with CAP), ALT, AST, hepatomegaly, hypertension, fasting blood sugar were significantly higher in H. pylori +ve group than H. pylori -ve group. After performing Linear regression of independent risk factors of NAFLD to prove or to refute the role of Helicobacter; H. pylori positivity, total cholesterol, degree of fatty liver by ultrasound, fasting blood sugar and diastolic blood pressure were independent risk factors for NAFLD.

CONCLUSION

Helicobacter pylori infection was independent risk factors for NAFLD and correlated with increased degree of steatosis.

Association between Helicobacter pylori infection and nonalcoholic fatty liver: A meta-analysis

BACKGROUND

Opinion regarding whether Helicobacter pylori infection can promote the occurrence and development of nonalcoholic fatty liver (NAFLD) is divided. Therefore, we aimed to assess the exact relationship between H pylori infection and NAFLD by integrating all available data.

METHODS

The articles about H pylori infection and NAFLD were collected by searching the databases of PubMed, Embase, Web of Science, Scopus, China National Knowledge Infrastructure, and WanFang. The random-effects model was used for data analysis, followed by subgroup analysis and meta-regression to explore sources of heterogeneity.

RESULTS

Twenty-one articles were included in the study. Pooled analysis showed that H pylori infection indeed promoted NAFLD. Subgroup analysis and regression analysis showed that case-control ratio may be one of the sources of heterogeneity.

CONCLUSIONS

H pylori infection is indeed one of the factors that promotes the progression of NAFLD for the Asian population. This provides new approaches for clinical prevention and treatment for NAFLD.

Helicobacter pylori eradication increases the serum high density lipoprotein cholesterol level in the infected patients with chronic gastritis: A single-center observational study

Background

Extra-gastric manifestation of Helicobacter pylori infection involves systemic inflammation, which results in the production of several cytokines. Only a few clinical trials have investigated the effect of H. pylori eradication therapy on lipid metabolism in the infected patients with chronic gastritis. We aimed to evaluate the effect of H. pylori eradication therapy on lipid metabolism in a Japanese population with chronic gastritis.

Methods

One hundred and sixty-three patients with H. pylori-associated chronic gastritis were enrolled in this study between June 2015 and March 2017. They underwent H. pylori eradication therapy; the effects of the therapy were assessed by the urea breath test performed at least 4 weeks after the therapy. After confirming H. pylori eradication, the health screening examination was repeated between May 2016 and August 2018. The clinical parameters were compared before and after the administration of the eradication therapy.

Results

The mean age of the enrolled patients was 56.7 years, and the mean follow-up duration was 514.7 days. Weight, body mass index, and obesity index were significantly increased post-eradication therapy compared to those pre-eradication therapy. White blood cell and platelet counts were significantly decreased, and high density lipoprotein cholesterol (HDL) level was significantly increased (P = 0.001), while low density lipoprotein cholesterol (LDL), total cholesterol, and triglycerides levels were not altered significantly. Hence, the LDL/HDL ratio was significantly decreased.

Conclusions

This study reported that H. pylori eradication therapy increase the HDL levels in the infected patients with chronic gastritis. Hence, the LDL/HDL ratio, which is used to evaluate the risk of atherosclerosis, was significantly decreased post-eradication therapy compared to that pre-eradication therapy.

Association between Helicobacter pylori infection and nonalcoholic fatty liver disease: a systemic review and meta-analysis

Although clinical studies have shown possible links of Helicobacter pylori infection with the development of nonalcoholic fatty liver disease (NAFLD), the results remain controversial. The aim of this meta-analysis is to investigate the association between H. pylori infection and NAFLD. A comprehensive search of relevant studies was performed up to November 2018. Data on H. pylori infection in NAFLD patients and controls were extracted. Odds ratio (OR) and 95% confidence interval (CI) were calculated using a random-effects model. Twelve studies involving 27 400 NAFLD patients and 60 347 controls were included. The pooled overall OR of H. pylori infection in NAFLD patients compared with controls was 1.36 (95% CI: 1.22-1.53, I=89.6%, P=0.000). Meta-regression and subgroup analysis showed that the sample size and the case-control ratio may have accounted for some of the heterogeneity. When stratified by publication year, the diagnostic method used for H. pylori, and Newcastle-Ottawa Scale scores, the OR remained significant. However, possible publication bias was observed. Of the 12 studies, six had carried out multivariable analysis after adjusting for potential confounders. The pooled results from these studies still indicated a higher risk of NAFLD in patients infected with H. pylori (OR=1.17, 95% CI: 1.01-1.36, I=72.4%, P=0.003). There is a 36% increased risk of NAFLD in patients with H. pylori infection. Further studies are warranted to investigate whether eradication of H. pylori is useful in the prevention and treatment of NAFLD.

Association between Helicobacter pylori infection and risk of nonalcoholic fatty liver disease: An updated meta-analysis

BACKGROUND

Recent studies that have examined the association between Helicobacter pylori infection and risk of nonalcoholic fatty liver disease (NAFLD) have produced conflicting data. We have performed a systematic review and meta-analysis to assess the association between H. pylori infection and risk of NAFLD.

METHODS

We searched PubMed, Web of Science and Scopus databases using predefined keywords to identify observational studies (published up to November 2018), in which NAFLD was diagnosed by histology, imaging or biochemistry. Data from selected studies were extracted and meta-analysis was performed using random-effects modeling. The statistical heterogeneity among studies (I²-index), subgroup analyses and the possibility of publication bias were assessed.

RESULTS

Thirteen observational (11 cross-sectional/case-control and 2 longitudinal) studies involving a total of 81,162 middle-aged individuals of predominantly Asian ethnicity (47.5% of whom had H. pylori infection diagnosed by urea breath test, faecal or serological tests) were included in the final analysis. Meta-analysis of data from cross-sectional and case-control studies showed that H. pylori infection was associated with increased risk of prevalent NAFLD (n = 11 studies; random-effects odds ratio [OR] 1.20, 95% CI 1.07-1.35; I² = 59.6%); this risk remained significant in those studies where analysis was fully adjusted for age, sex, smoking, adiposity measures, diabetes or dyslipidemia (random-effects OR 1.19, 95% CI 1.07-1.32, I² = 0%). Meta-analysis of data from longitudinal studies showed that H. pylori infection was also associated with increased NAFLD incidence (n = 2 studies; random-effects hazard ratio 1.14, 95% CI 1.05-1.23; I² = 0%). Sensitivity analyses did not alter these findings. Funnel plot did not reveal significant publication bias.

CONCLUSIONS

H. pylori infection is associated with mildly increased risk of both prevalent and incident NAFLD in middle-aged individuals. More prospective studies, particularly in non-Asian populations, and mechanistic studies are required to better elucidate the link between chronic H. pylori infection and NAFLD.

Functional Interactions between Gut Microbiota Transplantation, Quercetin, and High-Fat Diet Determine Non-Alcoholic Fatty Liver Disease Development in Germ-Free Mice

SCOPE

Modulation of intestinal microbiota has emerged as a new therapeutic approach for non-alcoholic fatty liver disease (NAFLD). Herein, it is addressed whether gut microbiota modulation by quercetin and intestinal microbiota transplantation can influence NAFLD development.

METHODS AND RESULTS

Gut microbiota donor mice are selected according to their response to high-fat diet (HFD) and quercetin in terms of obesity and NAFLD-related biomarkers. Germ-free recipients displayed metabolic phenotypic differences derived from interactions between microbiota transplanted, diets, and quercetin. Based on the evaluation of hallmark characteristics of NAFLD, it is found that gut microbiota transplantation from the HFD-non-responder donor and the HFD-fed donor with the highest response to quercetin results in a protective phenotype against HFD-induced NAFLD, in a mechanism that involves gut-liver axis alteration blockage in these receivers. Gut microbiota from the HFD-responder donor predisposed transplanted germ-free mice to NAFLD. Divergent protective and deleterious metabolic phenotypes exhibited are related to definite microbial profiles in recipients, highlighting the predominant role of Akkermansia genus in the protection from obesity-associated NAFLD development.

CONCLUSIONS

The results provide scientific support for the prebiotic capacity of quercetin and the transfer of established metabolic profiles through gut microbiota transplantation as a protective strategy against the development of obesity-related NAFLD.

Helicobacter pylori and non-alcoholic fatty liver disease: A new enigma?

BACKGROUND AND AIM

The relationship between Helicobacter pylori (H. pylori) and nonalcoholic fatty liver disease (NAFLD) is a matter of debate. We achieved this prospective work to study whether H. pylori infection is a risk factor for NAFLD.

METHODS

A cohort multicenter pilot study of 369 adults without NAFLD at baseline was followed up for 2 years. Serum leptin, insulin, tumor necrosis factor-α, adiponectin, and interleukin-6 were measured using an enzyme-linked immunosorbent assay (ELISA). Homeostasis model assessment of insulin resistance (HOMA-IR) and leptin/adiponectin ratio (LAR) were calculated. Fecal H. pylori antigen was measured by ELISA. A total of 127 participants with H. pylori positive were treated and then followed up for 3 months.

RESULTS

Helicobacter pylori-positive patients (46.3%) were associated with an increase in IR, proinflammatory cytokines, C-reactive protein (CRP), LAR, NAFLD-liver fat score (NAFLD-LFS), and hepatic steatosis index (HSI) (all P < 0.01). Multivariate analysis of NAFLD according to HSI and NAFLD-LFS reported that presence of H. pylori, LAR, CRP, IL-6, smoking, and age (all P < 0.01) were independent risk factors for the presence of NAFLD. Multiple models adjusted for potential mediators or confounders such as metabolic, inflammatory, and biochemical factors were constructed. After therapy of H. pylori infection, there was a significant reduction in lipogenic profile, IR, leptin, LAR, CRP, proinflammatory cytokines, HSI, and NAFLD-LFS, as well as, increasing HDL.

CONCLUSION

Helicobacter pylori infection was related to an increased risk of NAFLD development, through increased markers of IR, inflammatory mediators, and lipid metabolism. Moreover, its eradication can recover these NAFLD risk factors.

The associations among Helicobacter pylori infection, white blood cell count and nonalcoholic fatty liver disease in a large Chinese population

Reported relationships among Helicobacter pylori infection, white blood cell (WBC) count and nonalcoholic fatty liver disease (NAFLD) are inconsistent and controversial. We, therefore, conducted a cross-sectional study to investigate the associations among the presence of NAFLD, WBC count and H pylori infection, as diagnosed using the C-urea breath test (UBT).This study included 20,389 subjects enrolled at the International Health Care Center of the Second Affiliated Hospital of the Zhejiang University School of Medicine from January 2015 to December 2015. All participants underwent a C-UBT for the diagnosis of H pylori infection and ultrasonography for NAFLD as well as a blood test to determine WBC count. Multivariate logistic regression was then performed to evaluate the relationship among H pylori infection, WBC count and NAFLD.H pylori infection was detected in 38.49% (7,848/20,389) of the subjects via the UBT, and NAFLD was present in 37.24% (7,592/20,389) of the subjects. The prevalence of H pylori infection was higher in the NAFLD group than in the control group (41.25% vs 36.85%, P <.001). Significant differences were found between various WBC quartiles and H pylori infection, age, gender, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), high-sensitivity C-reactive protein (HS-CRP), glycosylated hemoglobin (HbA1c), triglyceride (TG), low-density lipoprotein (LDL-C), fasting blood glucose (FPG), homeostasis model assessment of insulin resistance (HOMA-IR), and smoking. Multivariate logistic regression revealed that the combination of H pylori infection and WBC count (odds ratio [OR] = 1.067, 95% confidence interval [CI]: 1.014, 1.093; P = .007; OR = 1.165, 95% CI: 1.023, 1.488; P <.001; OR = 1.183, 95% CI: 1.085, 1.559; P <.001, respectively) was positively associated with NAFLD.H pylori infection and WBC count may contribute to the pathogenesis of NAFLD.

Helicobacter pylori infection and liver diseases: Epidemiology and insights into pathogenesis

Both Helicobacter pylori (H. pylori) infection and liver diseases, including nonalcoholic fatty liver disease (NAFLD), viral hepatitis, and hepatocellular carcinoma (HCC), have high prevalences worldwide, and the relationship between H. pylori infection and liver disease has been discussed for many years. Although positive correlations between H. pylori and NAFLD have been identified in some clinical and experimental studies, negative correlations have also been obtained in high-quality clinical studies. Associations between H. pylori and the pathogenesis of chronic viral hepatitis, mainly disease progression with fibrosis, have also been suggested in some clinical studies. Concerning HCC, a possible role for H. pylori in hepatocarcinogenesis has been identified since H. pylori genes have frequently been detected in resected HCC specimens. However, no study has revealed the direct involvement of H. pylori in promoting the development of HCC. Although findings regarding the correlations between H. pylori and liver disease pathogenesis have been accumulating, the existing data do not completely lead to an unequivocal conclusion. Further high-quality clinical and experimental analyses are necessary to evaluate the efficacy of H. pylori eradication in ameliorating the histopathological changes observed in each liver disease.

Helicobacter pylori and extragastric diseases: A review

Helicobacter pylori (H. pylori) infection is very common and affects approximately half of the world population. It causes gastric diseases, but some authors have reported an association of H. pylori infection with other systemic manifestations beginning in 1994. The list of potential effects of H. pylori outside the stomach includes a number of extragastric manifestations and we focused on neurological, dermatological, hematologic, ocular, cardiovascular, metabolic, allergic, and hepatobiliary diseases. This review discusses these important reported manifestations that are not related to the gastrointestinal tract.

Diammonium Glycyrrhizinate Protects against Nonalcoholic Fatty Liver Disease in Mice through Modulation of Gut Microbiota and Restoration of Intestinal Barrier

Nonalcoholic fatty liver disease (NAFLD), as a common chronic liver disorder, is prevalent in the world. Recent evidence demonstrates that the "gut-liver axis" is related well to the progression of NAFLD, which regards gut microbiota and the intestinal barrier as two critical factors correlated with NAFLD. Diammonium glycyrrhizinate (DG), a compound of the natural bioactive pentacyclic triterpenoid glycoside, is the main component of licorice root extracts. The anti-inflammatory and liver protection effects of DG have already been reported, but to date, the mechanism has not been fully elucidated. In this research, we observed that DG reduced body weight, liver steatosis, as well as hepatic inflammation in NAFLD model mice induced by a high-fat diet. Illumina sequencing of the 16S rRNA revealed that DG intervention notably altered the composition of the gut microbiota in NAFLD mice. The richness of gut microbiota was significantly increased by DG. Specifically, DG reduced the Firmicutes-to- Bacteroidetes ratio and the endotoxin-producing bacteria such as Desulfovibrio and elevated the abundance of probiotics such as Proteobacteria and Lactobacillus. DG could augment the levels of short-chain fatty acid (SCFA)-producing bacteria such as Ruminococcaceae and Lachnospiraceae and promote SCFA production. In addition, DG supplementation dramatically alleviated the intestinal low-grade inflammation. Meanwhile, DG improved the expression of tight junction proteins, the goblet cell number, and mucin secretion and sequentially enhanced the function of intestinal barrier. Collectively, the prevention of NAFLD by DG might be mediated by modulating gut microbiota and restoring the intestinal barrier.

A Helicobacter pylori-associated insulin resistance in asymptomatic sedentary young men does not correlate with inflammatory markers and urine levels of 8-iso-PGF2-α or 1,4-dihydroxynonane mercapturic acid

A potential contribution of H. pylori contamination to low-grade inflammation, oxidative stress (OS) and insulin resistance as well as correlations between these parameters in asymptomatic sedentary males was analysed. We enrolled 30 apparently healthy asymptomatic young subjects (18 H. pylori negative and 12 positive) and measured whole blood glucose, glycated haemoglobin, insulin, C-peptide, cortisol, aldosterone, testosterone, thyroid stimulating hormone, C-reactive protein, interleukins 6 and 10, TNF-alpha and comet assay. As markers of OS, we used urine levels of iso-PGF₂-α and 1,4-dihydroxynonane mercapturic acid (DHN-MA). Twofold elevation of fasting insulin level and HOMA index in H. pylori-positive subjects (p < .05) was shown. Inflammatory parameters and monocyte DNA damage, urine levels of DHN-MA and iso-PGF2-α did not show significant differences between the groups. The early stage of H. pylori-triggered metabolic derangements in sedentary subjects include development of insulin resistance in H. pylori-positive subjects; however, there is no evidence of systemic inflammatory and OS-related changes.

Helicobacter pylori and Risk of Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

BACKGROUND/OBJECTIVES

Helicobacter pylori (H. pylori) is the most common chronic bacterial infection. Patients with H. pylori infection may be at an increased risk of nonalcoholic fatty liver disease (NAFLD) because of chronic inflammation and insulin resistance. Several epidemiologic studies attempting to determine this risk have yielded inconsistent results. This meta-analysis was conducted with the aims to summarize all available evidence and estimate the risk of NAFLD in patients with H. pylori infection.

METHODS

A literature search was performed using MEDLINE and EMBASE database from inception to June 2016. Studies that reported relative risks, odd ratios, or hazard ratios comparing the risk of NAFLD among patients with H. pylori infection versus without H. pylori infection were included. Pooled odds ratios and 95% confidence intervals were calculated using a random-effect, generic inverse variance method.

RESULTS

Six studies met our eligibility criteria and were included in this analysis. We found a statistically significant increased risk of NAFLD among patients with H. pylori infection with the pooled odds ratios of 1.21 (95% confidence interval, 1.07-1.37). The statistical heterogeneity was low with an I of 49%.

CONCLUSIONS

A significantly increased risk of NAFLD among patients with H. pylori infection was demonstrated in this meta-analysis. Further studies are required to clarify how this risk should be addressed in clinical practice.

Disruptions in gut microbial-host co-metabolism and the development of metabolic disorders

The microbial-mammalian metabolic axis has become recognized as an important component governing the overall homeostatic balance of the mammalian host. Disruption of the state of homeostasis among the gut microbiota has been shown to be causally linked to the development of host metabolic diseases including obesity, cardiovascular, diabetes, and fatty liver disease. This disruption is often referred to as gut dysbiosis. Gut dysbiosis leads to altered metabolic products derived from the microbiota and these in turn, typically shift the homeostatic metabolic balance of the host towards a low-grade chronic inflammation, a hallmark of metabolic syndrome. The primary objective of this review is to examine and discuss some very current research that has been done to study the effect of bacterial metabolites on host metabolism, sometimes referred to as microbiota-host co-metabolism. The metabolic conditions reviewed here include obesity, a known risk factor for all of the other metabolic conditions, as well as, cardiovascular disease, diabetes and nonalcoholic fatty liver disease. Only by further understanding the cause and result of gut dysbiosis will an adequate solution be found for metabolic disease, a viewpoint shared by many.

Association between Helicobacter pylori Infection and Nonalcoholic Fatty Liver Disease: A Single-Center Clinical Study

Objective

To investigate the association between Helicobacter pylori (H. pylori) infection and nonalcoholic fatty liver disease (NAFLD).

Methods

Data from 2051 participants who underwent ¹³C urea breath test and abdominal ultrasound examinations was collected. Participants were allocated to NAFLD risk group and NAFLD nonrisk group based on definite risk factors for NAFLD. The relationship between H. pylori infection and NAFLD was analyzed.

Results

No significant difference was found between rates of H. pylori infection and NAFLD using the chi-square test (P = 0.30) or regression analysis (P = 0.70). There was no significant difference between rates of H. pylori infection with and without NAFLD (P = 0.47) in the NAFLD risk group or in the NAFLD nonrisk group (P = 0.59). There was no significant difference between rates of H. pylori infection in men (P = 0.69) and in women (P = 0.27) or in participants aged 18–40 years (P = 0.43), 41–65 years (P = 0.14), and ≥66 years (P = 0.66) with and without NAFLD in the NAFLD risk group or between the same sex or age groups (P = 0.82, P = 0.66, P = 0.24, P = 0.53, and P = 1.00, resp.) in the NAFLD nonrisk group.

Conclusions

H. pylori infection does not appear to increase the NAFLD prevalence rate or to be associated with, or a risk factor for, NAFLD.

NAFLD, Helicobacter species and the intestinal microbiome

Non-alcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease worldwide. It is well-accepted that gut dysbiosis is associated with NAFLD, however, there is some conflicting evidence regarding the nature of these alterations. Infection with Helicobacter species, mainly H. pylori, has also been associated with increased NAFLD risk, however, some studies have failed to reproduce this finding. Further studies including large study samples and standardised procedures for microbiota analyses, H. pylori detection and NAFLD diagnostic criteria, are required. The mechanisms involving Helicobacter species and the intestinal microbiome in NAFLD pathogenesis appear to be part of the multiple-hit theory, in which increased intestinal permeability, inflammatory responses, altered choline, bile acids and carbohydrate metabolism, production of short-chain fatty acids, urea cycle and urea transport systems, altered maintenance of hepatic γδT-17 cells, insulin resistance, hormones secreted by the adipose tissue, metabolic hormones, bacterial metabolites and Helicobacter toxins, are all implicated.

A cohort study on Helicobacter pylori infection associated with nonalcoholic fatty liver disease

BACKGROUND

Previous studies have suggested a link between Helicobacter pylori (H. pylori) infection and nonalcoholic fatty liver disease (NAFLD), yet large-scale longitudinal studies are lacking to elucidate this association.

METHODS

A cohort study of 17,028 adults without NAFLD at baseline, who participated in a repeated health screening examination including an H. pylori-specific immunoglobulin G antibody test, was conducted to evaluate the association between H. pylori and NAFLD development. Fatty liver was diagnosed by ultrasonography.

RESULTS

During the 83,130 person-years follow-up, participants with H. pylori infection had a higher rate of incident NAFLD than those who were uninfected. In a multivariable model adjusted for age, sex, body mass index, smoking status, alcohol intake, regular exercise, year of screening exam, and education level, the hazard ratio (HR) for NAFLD development in participants with H. pylori infection compared to those without infection was 1.21 [95% confidence interval (CI), 1.10-1.34]. The association persisted after further adjustment for metabolic variables, inflammatory marker, and liver enzymes. The association between H. pylori and NAFLD was still evident in an analysis using fatty liver index as a surrogate marker of NAFLD. In addition, the association between H. pylori infection and incident NAFLD did not differ across clinically relevant subgroups evaluated.

CONCLUSIONS

H. pylori infection was significantly associated with the development of NAFLD, independent of metabolic and inflammatory risk factors. H. pylori infection may play a pathophysiologic role in NAFLD development, indicating that H. pylori eradication might play a role in reducing the risk of NAFLD.

Helicobacter pylori infection among patients with liver cirrhosis

BACKGROUND AND AIM

Inflammatory changes in the stomach caused by Helicobacter pylori indirectly and directly affect liver function. Moreover, the bacteria may worsen the course of the liver cirrhosis. The study aimed at evaluating the incidence of H. pylori infection among patients with liver cirrhosis, depending on the etiology and injury stage, scored according to Child-Pugh classification. Stage of esophageal varices and endoscopic inflammatory lesions in the stomach were evaluated, depending on the presence of H. pylori infection.

PATIENTS AND METHODS

The study included 147 patients with liver cirrhosis: 42 were infected with hepatitis C virus, 31 were infected with hepatitis B virus, 56 had alcoholic liver cirrhosis, and 18 had primary biliary cirrhosis. Diagnosis of H. pylori infection was performed based on the presence of immunoglobulin G antibodies in serum.

RESULTS

H. pylori infection was found in 46.9% of patients. The incidence of H. pylori infection among patients with postinflammatory liver cirrhosis was significantly higher (P=0.001), as compared with patients with alcoholic liver cirrhosis. Ammonia concentration was significantly higher in patients infected with H. pylori, compared with noninfected individuals (129 vs. 112 μmol/l; P=0.002). Incidence of H. pylori infection in patients without esophageal varices was significantly lower compared with patients with esophageal varices (14 vs. 60%; P<0.001).

CONCLUSION

H. pylori infection is significantly more frequent among patients with postinflammatory liver cirrhosis (infected with hepatitis C virus or hepatitis B virus) than in patients with alcoholic liver cirrhosis or primary biliary cirrhosis. H. pylori infection correlates with elevated concentration of blood ammonia and the incidence of esophageal varices.

Helicobacter pylori infection and extragastric diseases in 2017

The huge variety of extragastric diseases linked to Helicobacter pylori infection is widely known, and new studies are conducted every year on this topic. Neurological disorders and metabolic syndrome are some of the main issues debated in the most recent literature. Articles on the association of H. pylori with skin diseases, inflammatory bowel diseases, immunologic impairment, kidney dysfunction, allergic asthma, and respiratory diseases have been published as well. In this perspective, eradication therapy for this infection could become a mandatory measure in prevention strategy.

The Possible Role of Helicobacter pylori Infection in Non-alcoholic Fatty Liver Disease

Helicobacter pylori (H. pylori) which colonizes the stomach can cause a wide array of gastric disorders, including chronic gastritis, peptic ulcer, and gastric cancer. Recently, accumulating evidence has implicated H. pylori infection in extragastrointestinal diseases such as cardiovascular diseases, neurological disorders, and metabolic diseases. At the same time, many scholars have noted the relationship between H. pylori infection and non-alcoholic fatty liver disease (NAFLD). Despite the positive association between H. pylori and NAFLD reported in some researches, there are opposite perspectives denying their relationship. Due to high prevalence, unclear etiology and difficult treatment of NAFLD, confirming the pathogenicity of H. pylori infection in NAFLD will undoubtedly provide insights for novel treatment strategies for NAFLD. This paper will review the relationship between H. pylori infection and NAFLD and the possible pathogenic mechanisms.

The Association Between Helicobacter pylori Infection and Nonalcoholic Fatty Liver Disease

PURPOSE OF REVIEW

Helicobacter pylori (HP) infection is known to be a significant risk factor in the development of certain gastric conditions, such as ulcers, gastritis, and malignancy. Recently, however, the systemic effect of HP infection on other organ systems has come to be appreciated. In this review, we will explore the association between HP infection and nonalcoholic fatty liver disease (NAFLD), the hepatic component of metabolic syndrome.

RECENT FINDINGS

The possible association between HP infection and NAFLD initially stemmed from the isolation of HP bacteria in the livers of patients with NAFLD. Although there have been conflicting results, several subsequent clinical trials have demonstrated a higher rate of fatty liver and NASH in HP-positive patients compared to HP-negative patients; in addition, small trials examining the effect of HP eradication have shown improvement in markers of NAFLD activity, further supporting a link between these two conditions. The pathophysiology behind the possible association between HP infection and NAFLD has yet to be fully elucidated; several possible mechanisms include induction of a pro-inflammatory state that shifts the body toward a more lipogenic profile, and a hormonal shift that favors progression toward insulin resistance and fibrosis. The association between HP infection and NAFLD has been demonstrated in several clinical trials, including small trials evaluating the effect of HP eradication on NAFLD. Future studies examining the pathophysiology behind this association are the next step in characterizing the relationship between these two conditions.