Potential effect of chronic Helicobacter pylori infection on glucose metabolism of Mongolian gerbils

Increased Glycated Hemoglobin Levels in Patients With Helicobacter pylori Infection Are Associated With the Grading of Chronic Gastritis

Background

Recent studies have found an association between Helicobacter pylori infection and prediabetes. Whether H. pylori per se or host factors are involved in the disturbance of glycated hemoglobin needs further investigation. The aim of this study was to determine the association of glycated hemoglobin levels with endoscopic diagnosis and the inflammatory response in H. pylori infection.

Methods

A cross-sectional study was carried out in 88 dyspeptic non-diabetic adults who underwent esophagogastroduodenoscopy. The diagnosis of H. pylori infection was performed through urease test and histopathological exam. Cases were initially distributed into two groups: control (without H. pylori infection, n = 22) and HP (patients with H. pylori infection, n = 66). HbA1c was measured to determine prediabetes status according to the American Diabetes Association criteria, and then the groups were subdivided into non-prediabetic (n = 14), prediabetic (n = 8), non-prediabetic HP (n = 26) and prediabetic HP (n = 40) groups. Gastric mucosa was histologically evaluated to determine H. pylori density and inflammatory activity according to Sydney System. To investigate the balance of anti-inflammatory and pro-inflammatory cytokines we measured interleukin 10 (anti-inflammatory) and Tumor Necrosis Factor-a (pro-inflammatory) in the plasma or in the gastric mucosa.

Results

Patients with H. pylori infection had higher mean HbA1c levels than those without H. pylori infection. However, increased HbA1c levels were not associated with H. pylori-related factors but with the bacterial density, the intensity of inflammation and the activity of the chronic gastritis. In addition, H. pylori infection per se did not alter IL-10 and TNF-α neither in the plasma nor in the gastric mucosa, but the bacterial density was negatively correlated with systemic and local IL-10 expression. Although no correlation was found between systemic cytokines and HbA1c levels, local anti-inflammatory cytokine was correlated with HbA1c levels.

Conclusion

Long-term H. pylori infection is associated with prediabetes. This association is not related to the presence of H. pylori per se but depends on the extent of bacterial colonization and the degree of both local inflammation and activity of the chronic gastritis.

Factors influencing breath analysis results in patients with diabetes mellitus

Breath analysis is used to detect the composition of exhaled gas. As a quick and non-invasive detection method, breath analysis provides deep insights into the progression of various kinds of diseases, especially those with metabolism disorders. Abundant information on volatile compounds in diabetic patients has been studied in numerous articles in the literature. However, exhaled gas in diabetic patients can be altered by various complications. So far, little attention has been paid to this alteration. In our paper, we found that under air pollution conditions, diabetic patients exhale more nitric oxide. Diabetic patients with heart failure exhale more acetone than those without heart failure. After ¹³C-labeled glucose intake, patients infected with Helicobacter pylori exhaled more ¹³C and less ¹⁸O than those without infection. Exhalation with chronic kidney disease changes volatile organic compounds on a large scale. Diabetic patients with ketoacidosis exhale more acetone than those without ketoacidosis. Some specific volatile organic compounds also emanate from diabetic feet. By monitoring breath frequency, diabetic patients with obstructive sleep apnea syndrome exhibit a unique breath pattern and rhythm as compared with other diabetic patients, and sleep apnea is prevalent among diabetic patients. In addition to clinical findings, we analyzed the underlying mechanisms at the levels of molecules, cells and whole bodies, and provided suggestions for further studies.

Non-invasive diagnosis of type 2 diabetes in Helicobacter pylori infected patients using isotope-specific infrared absorption measurements

Helicobacter pylori causes several gastrointestinal diseases and may also contribute to the development of type 2 diabetes (T2D). Several studies suggest that there might be a potential link between H. pylori infection and T2D, but it still remains the subject of debate. Here, we first report the cumulative effect of H. pylori infection and T2D by exploiting the excretion kinetics of ¹³C/¹²C and ¹⁸O/¹⁶O isotope ratios of exhaled breath CO₂ in response to an oral dose of ¹³C-enriched glucose in individuals with T2D and non-diabetic controls (NDC) harbouring the H. pylori infection. Using a high-resolution integrated cavity output spectroscopy (ICOS) technique in the infrared region, we observed that the isotopic fractionations of ¹³C and ¹⁸O in breath CO₂ are distinctly altered in H. pylori infected T2D patients as well as in H. pylori infected NDC. Several optimal diagnostic cut-off points of ¹³C and ¹⁸O isotopes of breath CO₂ were also determined which exhibited the diagnostic sensitivity and specificity of ∼97 % and thus suggesting that breath ¹³C and ¹⁸O isotopes might be considered as potential biomarkers for the non-invasive assessment of the gastric pathogen prior to the onset of T2D. This may open a new diagnostic strategy for treating these common diseases in an alternative way.

[New aspects of Helicobacter pylori infection: Association with metabolic disturbances]

The review is devoted to the analysis of the literature on the possible association of Helicobacter pylori infection with type 2 diabetes mellitus, metabolic syndrome and its supposed mechanisms.

Helicobacter pylori Infection Aggravates Diet-induced Insulin Resistance in Association With Gut Microbiota of Mice

Emerging evidence suggests that Helicobacter pylori infection is associated with insulin resistance (IR) yet the underlying mechanisms are still obscure. The vital role of gut microbiota in triggering IR has been increasingly reported, however, no study has explored the correlation of gut microbiota and H. pylori-associated IR. Using H. pylori-infected mice model fed different diet structures, we demonstrated that H. pylori infection significantly aggravated high-fat diet (HFD)-induced metabolic disorders at the early stage, the extent of which was close to the effect of long-term HFD. Interestingly, we observed dynamic alterations in gut microbiota that were consistent with the changes in the metabolic phenotype induced by H. pylori and HFD. There may be an interaction among H. pylori, diet and gut microbiota, which dysregulates the host metabolic homeostasis, and treatment of H. pylori may be beneficial to the patients with impaired glucose tolerance in addition to diet control.

•

H. pylori infection aggravates high-fat diet induced metabolic disorders at the early stage in C57BL/6 mice.

•

H. pylori infection in high-fat diet induces dynamic alterations of gut microbiota consistent with the metabolic phynotype.

H. pylori is one of the most common human bacterial pathogens which causes gastric disorders. Epidemiological studies show that its infection is associated with insulin resistance although the mechanism is obscure. Our study demonstrates that H. pylori infection significantly aggravates high-fat diet induced metabolic disorders at the early stage, accompanied by dramatic alterations of gut microbiota. Moreover, the changes of gut microbiota are consistent with the metabolic phynotype, indicating an interaction among H. pylori, diet and gut microbiota. Thus, the treatment of H. pylori may be beneficial to the patients with impaired glucose tolerance in addition to diet control.