T-Cell Mineralocorticoid Receptor Deficiency Attenuates Pathologic Ventricular Remodelling After Myocardial Infarction.

BACKGROUND: Mineralocorticoid receptor (MR) antagonists have been widely used to treat heart failure (HF). Studies have shown that MR in T cells plays important roles in hypertension and myocardial hypertrophy. However, the function of T-cell MR in myocardial infarction (MI) has not been elucidated. METHODS: In this study, we used T-cell MR knockout (TMRKO) mouse to investigate the effects of T-cell MR deficiency on MI and to explore the underlying mechanisms. Echocardiography and tissue staining were used to assess cardiac function, fibrosis, and myocardial apoptosis after MI. Flow cytometry and quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect immune cell infiltration and inflammation. RESULTS: T-cell MR deficiency significantly improved cardiac function, promoted myocardial repair, and inhibited myocardial apoptosis, fibrosis, and inflammation after MI. Luminex assays revealed that TMRKO mice had significantly lower levels of interferon-gamma (IFN-γ) and interleukin-6 (IL-6) in serum and infarcted myocardium than littermate control mice. In cultured splenic T cells, MR deficiency suppressed IL-6 expression, whereas MR overexpression enhanced IL-6 expression. Chromatin immunoprecipitation (ChIP) assay demonstrated that MR bound to the MR response element on the promoter of IL-6 gene. Finally, T-cell MR deficiency significantly suppressed accumulation of macrophages in infarcted myocardium and differentiation of proinflammatory macrophages, thereby alleviating the consequences of MI. CONCLUSIONS: T-cell MR deficiency improved pathologic ventricular remodelling after MI, likely through inhibition of accumulation and differentiation of proinflammatory macrophages. At the molecular level, MR may work through IFN-γ and IL-6 in T cells to exert functions in MI.

The combination of experimental periodontitis and oral microbiota from periodontitis patients aggravates liver fibrosis in mice.

AIM: Periodontitis (PD) is the sixth most prevalent disease around the world and is involved in the development and progression of multiple systemic diseases. Previous studies have reported that PD may aggravate liver injuries. The objective of this study was to investigate whether and how PD affects liver fibrosis. MATERIALS AND METHODS: Ligature-induced PD (LIP) was induced in male C57/B6J mice, and sub-gingival plaques (PL) from patients with PD were applied to mouse teeth. Liver fibrosis was induced by carbon tetrachloride (CCl4 ) injection. The mice were randomly divided into six groups: Oil, Oil+LIP, Oil+LIP+PL, CCl4 , CCl4 +LIP, and CCl4 +LIP+PL. Alveolar bone resorption was evaluated by methylene blue staining. Hepatic function was analysed by serum alanine aminotransferase and hepatic hydroxyproline. Picrosirius red and α-smooth muscle actin (SMA) staining were used to evaluate the fibrotic area. RNA sequencing and quantitative RT-PCR were used to measure gene expression. Western blotting was used to measure protein levels. Flow cytometry was used to analyse the accumulation of immune cells. Mouse microbiota were analysed using 16S rRNA gene sequencing. RESULTS: Mice in the CCl4 +LIP+PL group displayed higher serum alanine aminotransferase and hepatic hydroxyproline as well as more Picrosirius red-positive and α-SMA-positive areas in liver samples than those of the CCl4 group, suggesting that PD (LIP+PL) aggravated CCl4 -induced hepatic dysfunction and liver fibrosis. Consistently, the expression of fibro-genic genes and the protein levels of transforming growth factor ß were much higher in the CCl4 +LIP+PL group than in the CCl4 group. Flow cytometry revealed that PD increased the accumulation of immune cells, including Kupffer cells, B cells, and Th17 cells, in the liver of mice with CCl4 treatment. PD also increased the expression of inflammatory genes and activated pro-inflammatory nuclear factor-kappa B pathway in the livers of CCl4 -injected mice. Moreover, PD altered both oral and liver microbiota in CCl4 -injected mice. CONCLUSIONS: PD aggravates CCl4 -induced hepatic dysfunction and fibrosis in mice, likely through the increase of inflammation and alteration of microbiota in the liver.

Sex-based differences in fecal short-chain fatty acid and gut microbiota in irritable bowel syndrome patients.

OBJECTIVE: To explore alterations in fecal short-chain fatty acids (SCFA) and gut microbiota in patients with diarrhea-predominant irritable bowel disease (IBS-D) and their relationships with clinical manifestations. METHODS: We recruited 162 patients with IBS-D and 66 healthy controls (HC). Their manifestations and psychological status were evaluated using the IBS severity scoring system and the Hospital Anxiety and Depression Scale (HADS). Colorectal visceral sensitivity was evaluated using a barostat. Systemic inflammation was evaluated using plasma cytokine levels. Fecal SCFA were quantified using ultra-performance liquid chromatography-tandem mass spectrometry, and fecal microbiota communities were analyzed using 16S rRNA sequencing. RESULTS: More men presented with IBS-D than women in our patient cohort. Patients with IBS-D had more severe manifestations, higher HADS score, and a higher rate of previous infectious enteritis than HC. Notably, female patients had significantly higher HADS scores than male patients. Male patients had significantly higher levels of plasma interleukin (IL)-12, fecal propionate and colorectal visceral sensitivity than male HC, while no differences were observed between female patients and female HC. Fecal acetate, butyrate and valerate correlated with the initial visceral sensory threshold, stressors, and IL-10 and IL-12 levels. The propionate-producing Prevotella 9 genus was significantly increased in male patients and positively correlated with fecal propionate. CONCLUSION: Distinct sex-based differences in clinical manifestations, fecal SCFA and microbiota richness are found in Chinese patients with IBS-D, which may be used to diagnose dysbiosis in these patients.

Berberine alleviates visceral hypersensitivity in rats by altering gut microbiome and suppressing spinal microglial activation.

Accumulating evidence shows that agents targeting gut dysbiosis are effective for improving symptoms of irritable bowel syndrome (IBS). However, the potential mechanisms remain unclear. In this study we investigated the effects of berberine on the microbiota-gut-brain axis in two rat models of visceral hypersensitivity, i.e., specific pathogen-free SD rats subjected to chronic water avoidance stress (WAS) and treated with berberine (200 mg· kg-1 ·d-1, ig, for 10 days) as well as germ-free (GF) rats subjected to fecal microbiota transplantation (FMT) from a patient with IBS (designated IBS-FMT) and treated with berberine (200 mg· kg-1 ·d-1, ig, for 2 weeks). Before the rats were sacrificed, visceral sensation and depressive behaviors were evaluated. Then colonic tryptase was measured and microglial activation in the dorsal lumbar spinal cord was assessed. The fecal microbiota was profiled using 16S rRNA sequencing, and short chain fatty acids (SCFAs) were measured. We showed that berberine treatment significantly alleviated chronic WAS-induced visceral hypersensitivity and activation of colonic mast cells and microglia in the dorsal lumbar spinal cord. Transfer of fecal samples from berberine-treated stressed donors to GF rats protected against acute WAS. FMT from a patient with IBS induced visceral hypersensitivity and pro-inflammatory phenotype in microglia, while berberine treatment reversed the microglial activation and altered microbial composition and function and SCFA profiles in stools of IBS-FMT rats. We demonstrated that berberine did not directly influence LPS-induced microglial activation in vitro. In both models, several SCFA-producing genera were enriched by berberine treatment, and positively correlated to the morphological parameters of microglia. In conclusion, activation of microglia in the dorsal lumbar spinal cord was involved in the pathogenesis of IBS caused by dysregulation of the microbiota-gut-brain axis, and the berberine-altered gut microbiome mediated the modulatory effects of the agent on microglial activation and visceral hypersensitivity, providing a potential option for the treatment of IBS.

Effect of the interleukin 10 polymorphisms on interleukin 10 production and visceral hypersensitivity in Chinese patients with diarrhea-predominant irritable bowel syndrome.

BACKGROUND: Irritable bowel syndrome (IBS), a functional gastrointestinal disorder, is characterized by cytokine imbalance. Previously, decreased plasma interleukin 10 (IL-10) level was reported in patients with IBS, which may be due to genetic polymorphisms. However, there are no reports correlating the IL-10 polymorphisms with IL-10 production in patients with IBS. This study aimed to analyze the effect of IL-10 polymorphisms on IL-10 production and its correlation with the clinical symptoms in Chinese patients with diarrhea-predominant IBS (IBS-D). METHODS: Two IL-10 single nucleotide polymorphisms (rs1800871 and rs1800896) were detected in 120 patients with IBS-D and 144 healthy controls (HC) using SNaPshot. IBS symptom severity score, Bristol scale, hospital anxiety, and depressive scale (HADS) were used to evaluate the clinical symptoms, as well as the psychological status and visceral sensitivity of the subjects. IL-10 levels in the plasma and peripheral blood mononuclear cell (PBMC) culture supernatant were measured using enzyme-linked immunosorbent assay, while those in ileal and colonic mucosal biopsies were measured using immunohistochemistry. RESULTS: The frequency of rs1800896 C allele was significantly lower in the patients with IBS-D than that in the HC (odds ratio: 0.49, 95% confidence interval: 0.27-0.92, P = 0.0240). The IL-10 levels in the plasma (P = 0.0030) and PBMC culture supernatant (P = 0.0500) of the CT genotype subjects were significantly higher than those in the TT genotype subjects. The CT genotype subjects exhibited a higher pain threshold in the rectal distention test than the TT genotype subjects. Moreover, IL-10 rs1800871 GG genotype subjects showed an increase in the HADS score compared to other genotype subjects. CONCLUSIONS: IL-10 rs1800896 C allele is correlated with higher IL-10 levels in the plasma and the PBMC culture supernatant, which is associated with a higher pain threshold in the Chinese patients with IBS-D. This study provides an explicit relationship of IL-10 polymorphisms with IL-10 production, which might help in understanding the pathogenesis of IBS-D.

Characteristic dysbiosis of gut microbiota of Chinese patients with diarrhea-predominant irritable bowel syndrome by an insight into the pan-microbiome.

BACKGROUND: Irritable bowel syndrome (IBS) is reported associated with the alteration of gut microbial composition termed as dysbiosis. However, the pathogenic mechanism of IBS remains unclear, while the studies of Chinese individuals are scarce. This study aimed to understand the concept of dysbiosis among patients with Chinese diarrhea-predominant IBS (IBS-D), as a degree of variance between the gut microbiomes of IBS-D population and that of a healthy population. METHODS: The patients with IBS-D were recruited (assessed according to the Rome III criteria, by IBS symptom severity score) from the Outpatient Department of Gastroenterology of Peking University Third Hospital, and volunteers as healthy controls (HCs) were enrolled, during 2013. The 16S rRNA sequences were extracted from fecal samples. Ribosomal database project resources, basic local alignment search tool, and SparCC software were used to obtain the phylotype composition of samples and the internal interactions of the microbial community. Herein, the non-parametric test, Wilcoxon rank-sum test was carried out to find the statistical significance between HC and IBS-D groups. All the P values were adjusted to q values to decrease the error rate. RESULTS: The study characterized the gut microbiomes of Chinese patients with IBS-D, and demonstrated that the dysbiosis could be characterized as directed alteration of the microbiome composition leading to greater disparity between relative abundance of two phyla, Bacteroidetes (Z = 4.77, q = 1.59 × 10) and Firmicutes (Z = -3.87, q = 5.83 × 10). Moreover, it indicated that the IBS symptom features were associated with the dysbiosis of whole gut microbiome, instead of one or several certain genera even they were dominating. Two genera, Bacteroides and Lachnospiracea incertae sedis, were identified as the core genera, meanwhile, the non-core genera contribute to a larger pan-microbiome of the gut microbiome. Furthermore, the dysbiosis in patients with IBS-D was associated with a reduction of network complexity of the interacted microbial community (HC vs. IBS-D: 639 vs. 154). The disordered metabolic functions of patients with IBS-D were identified as the potential influence of gut microbiome on the host (significant difference with q < 0.01 between HC and IBS-D). CONCLUSIONS: This study supported the view of the potential influence of gut microbiome on the symptom of Chinese patients with IBS-D, and further characterized dysbiosis in Chinese patients with IBS-D, thus provided more pathological evidences for IBS-D with the further understanding of dysbiosis.

[Evaluation on the safety and immunogenicity of Canada split influenza virus vaccine].

OBJECTIVE: To evaluate the safety and immunogenicity of Canada split influenza virus vaccine. METHODS: Cluster samples were by randomly chosen and divided into split vaccination group and homoimported influenza vaccination group. RESULTS: After injection, fever-reaction and local reaction rates of 'trial' group were found as 3.69% and 1.75% respectively, but no statistical significance was found when compared with 'control' group. However the antibody positive rates of 'trail' and 'control' groupsappeared statistically significant (H1N1: 96.8% vs. 92.3%, H3N2: 95.8% vs. 90.2%, B: 52.3% vs. 62.3%). For geometric mean titer (GMT) of type H1N1, H3H2 and B antibody, 'trial' group and 'control' group increased 22.4, 16.8, 8.2 and 21.2, 12.5 and 7.4 times respectively. The antibody protective rates of type H1N1, H3N2 and B were 99%, 99% and 53.9% for 'trial' group, and 96.2%, 98.4% and 62.3% for 'control' but with no statistically significant difference. CONCLUSION: Influenza split vaccine made in Shire company in Canada was safe and with good immunogenicity.