Helicobacter pylori infection worsens impaired glucose regulation in high-fat diet mice in association with an altered gut microbiome and metabolome

Association between non-insulin-based insulin resistance surrogate makers and Helicobacter pylori infection: a population-based study

BACKGROUND

Current evidence on the associations between insulin resistance (IR) and Helicobacter pylori (H. pylori) infection remains limited. This study aimed to investigate the association between non-insulin-based surrogate markers of IR, including the triglyceride glucose (TyG) index, triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio, and the metabolic score for IR (METS-IR), and H. pylori infection in U.S.

POPULATIONS

METHODS

This cross-sectional study involving 939 U.S. participants from the National Health and Nutrition Examination Survey (NHANES) 1999-2000. The associations between three IR surrogate markers and H. pylori infection were respectively investigated using logistic regression model, restricted cubic spline (RCS) curve and subgroup analysis.

RESULTS

Three IR surrogate markers levels were significantly elevated in H. pylori infection participants. There was a positive association between three IR surrogate markers and H. pylori infection, even after adjusting for potential confounding variables by three different models. In subgroup analysis, the adjusted association between three IR surrogate markers and H. pylori infection were more likely to be observed in female and Non-Hispanic White. Additionally, the RCS curve revealed a positive linear correlation between TyG index and H. pylori infection across all three models, and between METS-IR and H. pylori infection in Model 3. However, a positive nonlinear correlation was observed between TG/HDL-C ratio and H. pylori infection in all three models.

CONCLUSIONS

These findings suggest that non-insulin-based IR surrogate markers including TyG index, TG/HDL-C ratio, and METS-IR were all positively associated with H. pylori infection. These markers may serve as the potential indicators for identifying the risk of H. pylori infection in U.S.

POPULATIONS

CLINICAL TRIAL NUMBER

Not applicable.

Association of triglyceride-glucose index with Helicobacter pylori infection in the 1999-2000 NHANES cross-sectional study

Helicobacter pylori (H. pylori) infection is linked to metabolic syndrome and insulin resistance, with the triglyceride-glucose (TyG) index serving as a reliable marker for the latter. This study investigates the association between the TyG index and H. pylori infection. The study utilized cross-sectional data from the National Health and Nutrition Examination Survey (NHANES) conducted between 1999 and 2000. Participants underwent serologic testing for H. pylori, and the TyG index was calculated from fasting laboratory measurements. Multivariate logistic regression and restricted cubic spline methods were used to assess the association and explore the dose-response relationship. The analysis included 2984 participants. Elevated TyG index values were associated with an increased likelihood of H. pylori infection. The risk of infection rose with higher TyG index quartiles, with the highest quartile showing the most significant increase (OR = 1.54, 95% CI: 1.15-2.07, P = 0.004). A linear relationship between the TyG index and H. pylori infection was demonstrated. The study findings indicate a significant positive association between the TyG index and H. pylori infection. This association highlights the importance of metabolic health in the context of H. pylori infection and suggests that further research is needed to explore the potential implications for health promotion strategies.

Alzheimer's disease-like pathology induced by Porphyromonas gingivalis in middle-aged mice is mediated by NLRP3 inflammasome via the microbiota-gut-brain axis

BACKGROUND

Porphyromonas gingivalis (P. gingivalis) has been found to enter the brain and induce inflammation, contributing to Alzheimer's disease (AD). P. gingivalis is also closely linked to gut dysbiosis. However, does P. gingivalis induce AD-like pathology through the microbiota-gut-brain axis? There is limited literature on this topic.

OBJECTIVE

To determine the precise causal link among P. gingivalis, intestinal inflammation, and AD-related pathology.

METHODS

12- to 13-month-old female C57BL/6J mice were subjected to ligature placement and oral administration of P. gingivalis over a 24-week period. Then, cognitive performance was evaluated with behavioral tests, while AD neuropathological changes, neuroinflammation, and intestinal inflammation were assessed through qPCR, immunofluorescence, and western blot, and gut microbiota was analyzed by 16S rRNA.

RESULTS

Mice exposed to P. gingivalis showed impaired behavior in open field test, novel object recognition, and Y-maze tests. The bacterium infiltrated their brains, increasing Aβ42, AβPP, and Aβ fragments, promoting tau phosphorylation and microglial activation, and reducing levels of ZO-1, PSD95, SYP, and NeuN proteins. Inflammatory factors like NLRP3, caspase-1, IL-1β, IL-6, and TNF-α were elevated in both brains and intestine, while ZO-1 and occludin levels decreased in intestine. P. gingivalis also altered gut microbial compositions.

CONCLUSIONS

P. gingivalis induced gut dysbiosis and activated the NLRP3 inflammasome in the intestine and brains of mice. This led to impairment of both the intestinal and brain-blood barriers, triggering neuroinflammation and promoting the progression of AD. These findings highlight the critical role of NLRP3 inflammasome activation in the microbiota-gut-brain axis in the AD-like pathology induced by P. gingivalis.

Effect of Helicobacter pylori on sleeve gastrectomy and gastric microbiome differences in patients with obesity and diabetes

BACKGROUND

Obesity and diabetes mellitus (DM) have become public health concerns worldwide. Both conditions have severe consequences and are associated with significant medical costs and productivity loss. Additionally, Helicobacter pylori infection may be a risk factor for the development of these conditions. However, whether eradicating H. pylori infection directly causes weight loss or improves insulin sensitivity is unknown.

METHODS

In this study, we confirmed the effect of sleeve gastrectomy according to the state of the gastric microbiota in 40 patients with obesity, DM, and H. pylori infection. Patients with obesity were divided into four groups: non-DM without H. pylori infection (ND), non-DM with H. pylori infection (ND-HP), DM, and DM with H. pylori infection (DM-HP) using 16S V3-V4 sequencing.

RESULTS

In the DM group, ALT, hemoglobin, HbA1c, blood glucose, and HSI significantly decreased, whereas high-density lipoprotein significantly increased. However, in the H. pylori-positive group, no significant difference was observed. The diversity of gastric microbiota decreased in the order of the ND > DM > ND-HP > DM-HP groups. We also conducted a correlation analysis between the preoperative microbes and clinical data. In the ND-HP group, most of the top 20 gastric microbiota were negatively correlated with glucose metabolism. However, H. pylori infection was positively correlated with pre-insulin levels.

CONCLUSION

Therefore, these findings indicate that patients with obesity and diabetes clearly benefit from surgery, but H. pylori infection may also affect clinical improvement.

Helicobacter pylori seropositivity associates with hyperglycemia, but not obesity, in Danish children and adolescents

BACKGROUND

Helicobacter pylori colonizes the human stomach and may affect the inflammatory response, hormone production related to energy regulation, and gastrointestinal microbiota composition. Previous studies have explored a potential association between H. pylori infection and pediatric obesity with varying results. Considering the immunomodulatory effects of early-life infection with H. pylori that can confer beneficial effects, we hypothesized that we would find an inverse relationship between H. pylori seropositivity and obesity among Danish children and adolescents.

METHODS

We assessed H. pylori seroprevalence in 713 subjects from an obesity clinic cohort and 990 subjects from a population-based cohort, aged 6 to 19 years, and examined its association with obesity and other cardiometabolic risk factors.

RESULTS

No association was found between H. pylori and body mass index standard deviation score (BMI SDS). H. pylori seropositivity was, however, significantly associated with higher fasting plasma glucose levels and the prevalence of hyperglycemia.

CONCLUSION

While we did not find an association between H. pylori seropositivity and BMI SDS, we observed a significant association with higher fasting plasma glucose levels and increased prevalence of hyperglycemia, suggesting that H. pylori infection may contribute to impaired glucose regulation in Danish children and adolescents.

Artemisinin and its derivatives modulate glucose homeostasis and gut microbiota remodeling in a nutritional context

Glucose metabolic disorders, prevalent in numerous metabolic diseases, have become a pressing global public health concern. Artemisinin (ART) and its derivatives, including artesunate (ARTs) and artemether (ARTe), have shown potential as metabolic regulators. However, the specific effects of ART and its derivatives on glucose metabolism under varying nutritional conditions and the associated molecular mechanisms remain largely unexplored. In this study, we examined the impact of ART, ARTs, and ARTe on glucose homeostasis using a mouse model subjected to different dietary regimens. Our findings revealed that ART, ARTs, and ARTe increased blood glucose levels in mice on a normal-chow diet (ND) while mitigating glucose imbalances in high-fat diet (HFD) mice. Notably, treatment with ART, ARTs, and ARTe had contrasting effects on in vivo insulin signaling, impairing it in ND mice and enhancing it in HFD mice. Moreover, the composition of gut microbiota underwent significant alterations following administration of ART and its derivatives. In ND mice, these treatments reduced the populations of bacteria beneficial for improving glucose homeostasis, including Parasutterella, Alloprevotella, Bifidobacterium, Ileibacterium, and Alistipes. In HFD mice, there was an increase in the abundance of beneficial bacteria (Alistipes, Akkermanisia) and a decrease in bacteria known to negatively impact glucose metabolism (Coprobacillus, Helicobacter, Mucispirillum, Enterorhabdus). Altogether, ART, ARTs, and ARTe exhibited distinct effects on the regulation of glucose metabolism, depending on the nutritional context, and these effects were closely associated with modifications in gut microbiota composition.

Helicobacter pylori infection increases the risk of dyslipidemia in Chinese diabetic Population: a retrospective cross-sectional study

BACKGROUND

In contemporary times, increased prevalence of Helicobacter pylori (H. pylori) infection and elevated dyslipidemia levels present substantial public health challenges. However, the relationship between H. pylori and dyslipidemia remains inconclusive. No studies have yet conducted a population-based classification to investigate the impact of H. pylori infection on dyslipidemia in individuals with diabetes.

METHODS

A retrospective cohort study was carried out on a total of 60,535 individuals who underwent health check-ups at the Health Examination Center in Taizhou Hospital from 2017 to 2022. Physical measurements, hematological markers and detection of H. pylori were gathered from all patients. The study population was further stratified into diabetic and non-diabetic groups for analysis.

RESULTS

H. pylori infection was found to be an autonomous risk factor for dyslipidemia based on the results of multivariate logistic regression analysis (OR = 1.13, 95% CI: 1.03-1.24). However, no notable effect on dyslipidemia in the non-diabetic group was observed. Furthermore, at the follow-up, the group with persistent negative showed a significantly lower incidence ratio of dyslipidemia compared to the group with persistent infection (P = 0.006). The persistent negative group exhibited a significantly higher rate of improvement in dyslipidemia compared to the new infection group (P = 0.038).

CONCLUSIONS

In the diabetic population, the presence of H. pylori infection heightens the propensity for developing dyslipidemia. Therefore, the implementation of efficient eradication strategies for H. pylori infection could potentially lead to a decrease in the occurrence of dyslipidemia among individuals with diabetes.

The impact of diet, exercise, and sleep on Helicobacter pylori infection with different occupations: a cross-sectional study

BACKGROUND

Associations between Helicobacter pylori infection and lifestyle factors vary greatly by geographic location. This study aims to evaluate the prevalence of Helicobacter pylori infection in the Hunan cohort of central China and analyze the associations between Helicobacter pylori infection and lifestyle factors in different occupations.

METHODS

This was a cross-sectional study. Participants who received an annual physical examination were invited. Helicobacter pylori infection was detected by the 13 C-urea breath test. Self-reported physical examination questionnaires were used to analyze participants' demographic information, diet, exercise status, and sleep situations.

RESULTS

23254 participants finished this study. The Helicobacter pylori infection rate in the Hunan area was 25.8%, with the lowest prevalence in students (8.5%) and the highest prevalence in business managers (29.9%). The risk factors for Helicobacter pylori infection were marital status (divorced or married) (OR:1.16, 95%CI:1.090-1.234), overeating (OR:1.105, 95%CI: 1.001-1.220), and consumption of eggs (OR:1.047, 95%CI:1.004-1.092), animal viscera (OR: 1.077, 95%CI:1.014-1.144) and coffee (OR:1.074, 95%CI:1.019-1.132). Participants' education level (OR:0.911, 95%CI:0.881-0942), consumption of midnight snack (OR:0.926, 95%CI:0.877-0.977), and vegetable (OR:0.927, 95%CI: 0.884-0.972) were protective factors against Helicobacter pylori infection. Whether participants exercised regularly or had sleep problems had no significant effect on Helicobacter pylori infection. Different professionals showed significant differences in the rates of overeating, eating three meals on time, midnight snack, and consuming coffee, eggs, animal viscera, and vegetables > 3 times/week (P values < 0.05).

CONCLUSIONS

Helicobacter pylori infection showed a significant relationship with dietary factors, but not significantly with sleep and exercise factors. Different occupations showed different dietary tendencies related to Helicobacter pylori infection. The design of an occupation-based Helicobacter pylori screening and prevention program is supported.

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.

Interactions between Helicobacter pylori infection and host metabolic homeostasis: A comprehensive review

The microbiota actively and extensively participates in the regulation of human metabolism, playing a crucial role in the development of metabolic diseases. Helicobacter pylori (H. pylori), when colonizing gastric epithelial cells, not only induces local tissue inflammation or malignant transformation but also leads to systemic and partial changes in host metabolism. These shifts can be mediated through direct contact, toxic components, or indirect immune responses. Consequently, they influence various molecular metabolic events that impact nutritional status and iron absorption in the host. Unraveling the intricate and diverse molecular interaction links between H. pylori and human metabolism modulation is essential for understanding pathogenesis mechanisms and developing targeted treatments for related diseases. However, significant challenges persist in comprehensively understanding the complex association networks among H. pylori itself, the infected host's status, the host microbiome, and the immune response. Previous metabolomics research has indicated that H. pylori infection and eradication may selectively shape the metabolite and microbial profiles of gastric lesions. Yet, it remains largely unknown how these diverse metabolic pathways, including isovaleric acid, cholesterol, fatty acids, and phospholipids, specifically modulate gastric carcinogenesis or affect the host's serum metabolism, consequently leading to the development of metabolic-associated diseases. The direct contribution of H. pylori to metabolisms still lacks conclusive evidence. In this review, we summarize recent advances in clinical evidence highlighting associations between chronic H. pylori infection and metabolic diseases, as well as its potential molecular regulatory patterns.

Persistent Helicobacter pylori infection leads to elevated fasting plasma glucose level: A retrospective cohort study based on a nondiabetes Chinese population

BACKGROUND AND AIM

The relationship between Helicobacter pylori (H. pylori) and fast plasma glucose (FPG) on nondiabetes populations is still inconclusive. Nowadays, not only the high infection rate of H. pylori but also the high FPG level is threatening the Chinese people.

METHODS

A retrospective cohort study has been established to analyze the relationship between H. pylori infection and FPG level, 18 164 individuals performed healthy examination in Taizhou Hospital Health Examination Center from 2017 to 2022 were included, and hematological indicators, body parameters, and H. pylori detection by 13 C-urea breath test were collected from patients. The follow-up intervals were greater than 12 months.

RESULTS

H. pylori infection was regarded as an independent risk factor for elevated FPG after multivariate logistic regression. Additionally, the average interval time were 33.6 ± 13.3 months. Mean changed FPG values in the persistent infection group were higher than in the subgroup of persistent negative (P = 0.029) as well as eradication infection (P = 0.007). The aforementioned changes began to appear after 2 years of follow-up. Similarly, when compared with the subgroup of persistent infection, mean changed triglyceride/high density lipoprotein (TG/HDL) values were much lower in the subgroup of persistent negative (P = 0.008) and eradication infection (P = 0.018), but the differences appeared after 3 years of follow-up.

CONCLUSIONS

H. pylori infection is an independent risk factor for elevated FPG in non-diabetes mellitus (DM) individuals. Persistent H. pylori infection causes an increase in FPG level and TG/HDL, which may be a risk factor for diabetes mellitus.

The Potential Effects of Isoleucine Restricted Diet on Cognitive Impairment in High-Fat-Induced Obese Mice via Gut Microbiota-Brain Axis

SCOPE

Obesity induced by high-fat diet (HFD) can cause lipid metabolism disorders and cognitive impairment. Isoleucine restriction can effectively alleviate lipid metabolism disorders caused by HFD but the underlying mechanisms on cognition are unknown.

METHODS AND RESULTS

Thirty 3-month-old C57BL/6J mice are divided equally into the following groups: the control group, HFD group, and HFD Low Ile group (67% reduction in isoleucine in high fat feeds). Feeding for 11 weeks with behavioral testing, which shows that isoleucine restriction attenuates HFD-induced cognitive dysfunction. As observed by staining, isoleucine restriction inhibits HFD-induced neuronal damage and microglia activation. Furthermore, isoleucine restriction significantly increases the relative abundance of gut microbiota, decreases the proportion of Proteobacteria, and reduces the levels of lipopolysaccharide (LPS) in serum and brain. Isoleucine restriction reduces protein expression of TLR4/MyD88/NF-κB signaling pathway and inhibits upregulation of proinflammatory cytokine genes and protein expression in mice brain. In addition, isoleucine restriction significantly improves insulin resistance in the brain as well as synaptic plasticity impairment.

CONCLUSION

Isoleucine restriction may be a potential intervention to reduce HFD-induced cognitive impairment by altering gut microbiota, reducing neuroinflammation, insulin resistance, and improving synaptic plasticity in mice brain.

FG-4592 relieves diabetic kidney disease severity by influencing metabolic profiles via gut microbiota reconstruction in both human and mouse models

Objective: Diabetic kidney disease (DKD) is one of the most prevalent complications of diabetes mellitus (DM) and is highly associated with devastating outcomes. Hypoxia-inducible factor (HIF), the main transcription factor that regulates cellular responses to hypoxia, plays an important role in regulating erythropoietin (EPO) synthesis. FG-4592 is the HIF stabilizer that is widely used in patients with renal anemia. We investigated the effect of FG-4592 on DKD phenotypes and the pharmacologic mechanism from the perspective of gut microbiota and systemic metabolism. Design: We collected the clinical data of 73 participants, including 40 DKD patients with combined renal anemia treated with FG-4592, and 33 clinical index-matched DKD patients without FG-4592 treatment from The First Affiliated Hospital of Zhengzhou University at the beginning and after a 3-6-month follow-up period. We established DKD mouse models treated by FG-4592 and performed fecal microbiota transplantation from FG-4592-treated DKD mice to investigate the effects of FG-4592 on DKD and to understand this mechanism from a microbial perspective. Untargeted metabolome-microbiome combined analysis was implemented to globally delineate the mechanism of FG-4592 from both microbial and metabolomic aspects. Result: DKD phenotypes significantly improved after 3-6 months of FG-4592 treatment in DKD patients combined with renal anemia, including a decreased level of systolic blood pressure, serum creatinine, and increased estimated glomerular infiltration rate. Such effects were also achieved in the DKD mouse model treated with FG-4592 and can be also induced by FG-4592-influenced gut microbiota. Untargeted plasma metabolomics-gut microbiota analysis showed that FG-4592 dramatically altered both the microbial and metabolic profiles of DKD mice and relieved DKD phenotypes via upregulating beneficial gut microbiota-associated metabolites. Conclusion: FG-4592 can globally relieve the symptoms of DKD patients combined with renal anemia. In the animal experiment, FG-4592 can reconstruct the intestinal microbial profiles of DKD to further upregulate the production of gut-associated beneficial metabolites, subsequently improving DKD phenotypes.

Metabolic alterations in patients with Helicobacter pylori-related gastritis: The H. pylori-gut microbiota-metabolism axis in progression of the chronic inflammation in the gastric mucosa

PURPOSE

To characterize the serum metabolism in patients with Helicobacter pylori-positive and H. pylori-negative gastritis.

METHODS

Clinical data and serum gastric function parameters, PGI (pepsinogen I), PGII, PGR (PGI/II), and G-17 (gastrin-17) of 117 patients with chronic gastritis were collected, including 57 H. pylori positive and 60 H. pylori negative subjects. Twenty cases in each group were randomly selected to collect intestinal mucosa specimens and serum samples. The gut microbiota profiles were generated by 16S rRNA gene sequencing, and the serum metabolites were analyzed by a targeted metabolomics approach based on liquid chromatography-mass spectrometry (LC-MS) technology.

RESULTS

Altered expression of 20 metabolites, including isovaleric acid, was detected in patients with HPAG. Some taxa of Bacteroides, Fusobacterium, and Prevotella in the gut microbiota showed significant correlations with differentially expressed metabolites between H. pylori positive and H. pylori negative individuals. As a result, an H. pylori-gut microbiota-metabolism (HGM) axis was proposed.

CONCLUSION

Helicobacter pylori infection may influence the progression of mucosal diseases and the emergence of other complications in the host by altering the gut microbiota, and thus affecting the host serum metabolism.

DHA-enriched phosphatidylserine alleviates high fat diet-induced jejunum injury in mice by modulating gut microbiota

A long-term high-fat diet (HFD) is one of the high-risk factors for intestinal barrier damage. Docosahexaenoic acid-enriched phosphatidylserine (DHA-PS) has multiple biological activities, while its protective effect on HFD-caused jejunum injury remains unknown. Thus, the present study investigated the protective effect of DHA-PS on HFD-induced jejunum injury in mice. Our results showed that DHA-PS (100 mg per kg per d) could protect against HFD-caused jejunum injury by decreasing the levels of inflammatory factors such as interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) in the serum and jejunum tissues, with histological analysis confirming this injury amelioration. Additionally, DHA-PS alleviated the HFD-caused oxidative stress by decreasing malondialdehyde (MDA) and increasing total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) levels in the jejunum. Moreover, DHA-PS significantly increased the expression of tight junction proteins (ZO-1, occludin, and claudin-4) in the jejunum, and modulated the HFD-induced gut microbiota disorder by decreasing the Firmicutes and Bacteroidetes ratio, and reducing the relative abundance of Lachnoclostridium, Coriobacteriaceae, Desulfovibrionaceae, and Helicobacter, while increasing the relative abundance of Lachnospiraceae_NK4A136_group, Alistipes, norank_f__Muribaculaceae, and Bacteroides. Overall, these results support that DHA-PS can alleviate the HFD-caused jejunum injury.

Depletion of Gut Microbiota Inhibits Hepatic Lipid Accumulation in High-Fat Diet-Fed Mice

Dysregulated lipid metabolism is a key pathology in metabolic diseases and the liver is a critical organ for lipid metabolism. The gut microbiota has been shown to regulate hepatic lipid metabolism in the host. However, the underlying mechanism by which the gut microbiota influences hepatic lipid metabolism has not been elucidated. Here, a gut microbiota depletion mouse model was constructed with an antibiotics cocktail (Abx) to study the mechanism through which intestinal microbiota regulates hepatic lipid metabolism in high-fat diet (HFD)-fed mice. Our results showed that the Abx treatment effectively eradicated the gut microbiota in these mice. Microbiota depletion reduced the body weight and fat deposition both in white adipose tissue and liver. In addition, microbiota depletion reduced serum levels of glucose, total cholesterol (TC), low-density lipoproteins (LDL), insulin, and leptin in HFD-fed mice. Importantly, the depletion of gut microbiota in HFD-fed mice inhibited excessive hepatic lipid accumulation. Mechanistically, RNA-seq results revealed that gut microbiota depletion changed the expression of hepatic genes involved in cholesterol and fatty acid metabolism, such as Cd36, Mogat1, Cyp39a1, Abcc3, and Gpat3. Moreover, gut microbiota depletion reduced the abundance of bacteria associated with abnormal metabolism and inflammation, including Lachnospiraceae, Coriobacteriaceae_UCG-002, Enterorhabdus, Faecalibaculum, and Desulfovibrio. Correlation analysis showed that there was strong association between the altered gut microbiota abundance and the serum cholesterol level. This study indicates that gut microbiota ameliorates HFD-induced hepatic lipid metabolic dysfunction, which might be associated with genes participating in cholesterol and fatty acid metabolism in the liver.

Phenylalanine impairs insulin signaling and inhibits glucose uptake through modification of IRβ

Whether amino acids act on cellular insulin signaling remains unclear, given that increased circulating amino acid levels are associated with the onset of type 2 diabetes (T2D). Here, we report that phenylalanine modifies insulin receptor beta (IRβ) and inactivates insulin signaling and glucose uptake. Mice fed phenylalanine-rich chow or phenylalanine-producing aspartame or overexpressing human phenylalanyl-tRNA synthetase (hFARS) develop insulin resistance and T2D symptoms. Mechanistically, FARS phenylalanylate lysine 1057/1079 of IRβ (F-K1057/1079), inactivating IRβ and preventing insulin from promoting glucose uptake by cells. SIRT1 reverse F-K1057/1079 and counteract the insulin-inactivating effects of hFARS and phenylalanine. F-K1057/1079 and SIRT1 levels in white blood cells from T2D patients are positively and negatively correlated with T2D onset, respectively. Blocking F-K1057/1079 with phenylalaninol sensitizes insulin signaling and relieves T2D symptoms in hFARS-transgenic and db/db mice. These findings shed light on the activation of insulin signaling and T2D progression through inhibition of phenylalanylation.

Whether amino acids act on cellular insulin signaling remains unclear. Here, the authors find that phenylalanine modifies insulin receptor beta (IRβ) and inactivates insulin signaling and glucose uptake and positively correlated with T2D onset.

Altered Gut Microbiota and Short-Chain Fatty Acids After Vonoprazan-Amoxicillin Dual Therapy for Helicobacter pylori Eradication

The combination of vonoprazan (VPZ) and amoxicillin (VA therapy) has been shown to achieve acceptable eradication rates for Helicobacter pylori (H. pylori). Herein, our aim was to explore the short-term effect of VA therapy on the gut microbiota and short-chain fatty acids (SCFAs) using human fecal samples. A total of 119 H. pylori-positive patients were randomized into low- or high-dose VA therapy (i.e., amoxicillin 1 g b.i.d. or t.i.d. and VPZ 20 mg b.i.d.) for 7 or 10 days. Thirteen H. pylori-negative patients served as controls. Fecal samples were collected from H. pylori-positive and H. pylori-negative patients. The gut microbiota and SCFAs were analyzed using 16S rRNA gene sequencing and gas chromatography-mass spectrometry, respectively. The gut microbiota in H. pylori-positive patients exhibited increased richness, diversity, and better evenness than matched patients. Fifty-three patients studied before and after H. pylori eradication were divided into low (L-VA) and high (H-VA) amoxicillin dose groups. The diversity and composition of the gut microbiota among L-VA patients exhibited no differences at the three time points. However, among H-VA patients, diversity was decreased, and the microbial composition was altered immediately after H-VA eradication but was restored by the confirmation time point. The decreased abundance of Anaerostipes, Dialister, and Lachnospira induced by H-VA was associated with altered SCFA levels. VA dual therapy for H. pylori eradication has minimal negative effects on gut microbiota and SCFAs.

The harmful intestinal microbial community accumulates during DKD exacerbation and microbiome-metabolome combined validation in a mouse model

OBJECTIVE

Diabetic kidney disease (DKD) is one of the most prevalent complications of diabetes mellitus (DM) and is associated with gut microbial dysbiosis. We aim to build a diagnostic model to aid clinical practice and uncover a crucial harmful microbial community that contributes to DKD pathogenesis and exacerbation.

DESIGN

A total of 528 fecal samples from 180 DKD patients and 348 non-DKD populations (138 DM and 210 healthy volunteers) from the First Affiliated Hospital of Zhengzhou University were recruited and randomly divided into a discovery phase and a validation phase. The gut microbial composition was compared using 16S rRNA sequencing. Then, the 180 DKD patients were stratified into four groups based on clinical stages and underwent gut microbiota analysis. We established DKD mouse models and a healthy fecal microbiota transplantation (FMT) model to validate the effects of gut microbiota on DKD and select the potential harmful microbial community. Untargeted metabolome-microbiome combined analysis of mouse models helps decipher the pathogenetic mechanism from a metabolic perspective.

RESULTS

The diversity of the gut microbiome was significantly decreased in DKD patients when compared with that of the non-DKD population and was increased in the patients with more advanced DKD stages. The DKD severity in mice was relieved after healthy gut microbiota reconstruction. The common harmful microbial community was accumulated in the subjects with more severe DKD phenotypes (i.e., DKD and DKD5 patients and DKD mice). The harmful microbial community was positively associated with the serum injurious metabolites (e.g., cholic acid and hippuric acid).

CONCLUSION

The fecal microbial community was altered markedly in DKD. Combining the fecal analysis of both human and animal models selected the accumulated harmful pathogens. Partially recovering healthy gut microbiota can relieve DKD phenotypes via influencing pathogens' effect on DKD mice's metabolism.

Impact of Dietary Patterns on H. pylori Infection and the Modulation of Microbiota to Counteract Its Effect. A Narrative Review

Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the stomach and can induce gastric disease and intra-gastric lesions, including chronic gastritis, peptic ulcers, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. This bacterium is responsible for long-term complications of gastric disease. The conjunction of host genetics, immune response, bacterial virulence expression, diet, micronutrient availability, and microbiome structure influence the disease outcomes related to chronic H. pylori infection. In this regard, the consumption of unhealthy and unbalanced diets can induce microbial dysbiosis, which infection with H. pylori may contribute to. However, to date, clinical trials have reported controversial results and current knowledge in this field is inconclusive. Here, we review preclinical studies concerning the changes produced in the microbiota that may be related to H. pylori infection, as well as the involvement of diet. We summarize and discuss the last approaches based on the modulation of the microbiota to improve the negative impact of H. pylori infection and their potential translation from bench to bedside.

The remodel of the "central dogma": a metabolomics interaction perspective

BACKGROUND

In 1957, Francis Crick drew a linear diagram on a blackboard. This diagram is often called the "central dogma." Subsequently, the relationships between different steps of the "central dogma" have been shown to be considerably complex, mostly because of the emerging world of small molecules. It is noteworthy that metabolites can be generated from the diet through gut microbiome metabolism, serve as substrates for epigenetic modifications, destabilize DNA quadruplexes, and follow Lamarckian inheritance. Small molecules were once considered the missing link in the "central dogma"; however, recently they have acquired a central role, and their general perception as downstream products has become reductionist. Metabolomics is a large-scale analysis of metabolites, and this emerging field has been shown to be the closest omics associated with the phenotype and concomitantly, the basis for all omics.

AIM OF REVIEW

Herein, we propose a broad updated perspective for the flux of information diagram centered in metabolomics, including the influence of other factors, such as epigenomics, diet, nutrition, and the gut- microbiome.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Metabolites are the beginning and the end of the flux of information.