Tauroursodeoxycholic Acid Reverses Dextran Sulfate Sodium-Induced Colitis in Mice via Modulation of Intestinal Barrier Dysfunction and Microbiome Dysregulation.

Ulcerative colitis (UC) is an immune-mediated inflammatory disease that can lead to persistent damage and even cancer without any intervention. Conventional treatments can alleviate UC symptoms but are costly and cause various side effects. Tauroursodeoxycholic acid (TUDCA), a secondary bile acid derivative, possesses anti-inflammatory and cytoprotective properties for various diseases, but its potential therapeutic benefits in UC have not been fully explored. Mice were subjected to colitis induction using 3% dextran sulfate sodium (DSS). The therapeutic effect of TUDCA was evaluated by body weight loss, disease activity index (DAI), colon length, and spleen weight ratio. Tissue pathology was assessed using H&E staining, while the levels of pro-inflammatory and anti-inflammatory cytokines in colonic tissue were quantified via ELISA. Tight junction proteins were detected by immunoblotting and intestinal permeability was assessed using fluorescein isothiocyanate (FITC)-dextran. Moreover, the gut microbiota was profiled using high-throughput sequencing of the 16S rDNA gene. TUDCA alleviated the colitis in mice, involving reduced DAI, attenuated colon and spleen enlargement, ameliorated histopathological lesions, and normalized levels of pro-inflammatory and anti-inflammatory cytokines. Furthermore, TUDCA treatment inhibited the downregulation of intestinal barrier proteins, including zonula occludens-1 and occludin, thus reducing intestinal permeability. The analysis of gut microbiota suggested that TUDCA modulated the dysbiosis in mice with colitis, especially for the remarkable rise in Akkermansia TUDCA exerted a therapeutic efficacy in DSS-induced colitis by reducing intestinal inflammation, protecting intestinal barrier integrity, and restoring gut microbiota balance. SIGNIFICANCE STATEMENT: This study demonstrates the potential therapeutic benefits of Tauroursodeoxycholic acid (TUDCA) in ulcerative colitis. TUDCA effectively alleviated colitis symptoms in mice, including reducing inflammation, restoring intestinal barrier integrity and the dysbiosis of gut microbiota. This work highlights the promising role of TUDCA as a potentially alternative treatment, offering new insights into managing this debilitating condition.

Dihydromyricetin improves DSS-induced colitis in mice via modulation of fecal-bacteria-related bile acid metabolism.

Recent studies show that the nutraceutical supplement dihydromyricetin (DHM) can alleviate IBD in murine models by downregulating the inflammatory pathways. However, the molecular mechanistic link between the therapeutic efficiency of DHM, gut microbiota, and the metabolism of microbial BAs remains elusive. In this study, we explored the improvement of DHM on the dysregulated gut microbiota of mice with dextran sulfate sodium (DSS)-induced colitis. We found that DHM could markedly improve colitis symptoms, gut barrier disruption, and colonic inflammation in DSS-treated mice. In addition, bacterial 16S rDNA sequencing assay demonstrated that DHM could alleviate gut dysbiosis in mice with colitis. Furthermore, antibiotic-mediated depletion of the gut microflora and fecal microbiome transplantation (FMT) demonstrated that the therapeutic efficiency of DHM was closely associated with gut microbiota. BA-targeted metabolomics analysis revealed that DHM restored the metabolism of microbial BAs in the gastrointestinal tract during the development of colitis. DHM significantly enriched the proportion of the beneficial Lactobacillus and Akkermansia genera, which were correlated with increased gastrointestinal levels of unconjugated BAs involving chenodeoxycholic acid and lithocholic acid, enabling the BAs to activate specific receptors, such as FXR and TGR5, and maintaining intestinal integrity. Taken together, DHM could alleviate DSS-induced colitis in mice by restoring the dysregulated gut microbiota and BA metabolism, leading to improvements in intestinal barrier function and colonic inflammation. Increased microbiota-BAs-FXR/TGR5 signaling may be the potential targets of DHM in colitis. Therefore, our findings provide novel insights into the development of novel DHM-derived drugs for the management of IBD.

Berberine improves colitis by triggering AhR activation by microbial tryptophan catabolites.

Inflammatory bowel diseases (IBD) are kind of recurrent inflammatory issues that occur in the gastrointestinal tract, and currently clinical treatment is still unideal due to the complex pathogenesis of IBD. Basically, gut barrier dysfunction is triggered by gut microbiota dysbiosis that is closely associated with the development of IBD, we thus investigated the therapeutic capacity of berberine (BBR) to improve the dysregulated gut microbiota, against IBD in rats, using a combinational strategy of targeted metabolomics and 16 s rDNA amplicon sequencing technology. Expectedly, our data revealed that BBR administration could greatly improve the pathological phenotype, gut barrier disruption, and the colon inflammation in rats with dextran sulfate sodium (DSS)-induced colitis. In addition, 16S rDNA-based microbiota analysis demonstrated that BBR could alleviate gut dysbiosis in rats. Furthermore, our targeted metabolomics analysis illustrated that the levels of microbial tryptophan catabolites in the gastrointestinal tract were significantly changed during the development of the colitis in rats, and BBR treatment can significantly restore such changes of the tryptophan catabolites accordingly. At last, our in vitro mechanism exploration was implemented with a Caco-2 cell monolayer model, which verified that the modulation of the dysregulated gut microbiota to change microbial metabolites coordinated the improvement effect of BBR on gut barrier disruption in the colitis, and we also confirmed that the activation of AhR induced by microbial metabolites is indispensable to the improvement of gut barrier disruption by BBR. Collectively, BBR has the capacity to treat DSS-induced colitis in rats through the regulation of gut microbiota associated tryptophan metabolite to activate AhR, which can greatly improve the disrupted gut barrier function. Importantly, our finding elucidated a novel mechanism of BBR to improve gut barrier function, which holds the expected capacity to promote the BBR derived drug discovery and development against the colitis in clinic setting.

Protective effects and possible molecular mechanism of Hovenia dulcis Thunb. extract on acetaminophen-induced hepatotoxicity.

Hovenia dulcis Thunb. is a traditional hepatoprotective Chinese medicine, and in research, much effort has been focused on the protection against alcoholic liver injury. In this study, the protective effects of a fruit ethanol extract of Hovenia dulcis (FE) against APAP-induced acute hepatotoxicity in mice and the possibly involved molecular mechanisms were investigated. Hepatoprotective activity of FE is clearly indicated by histopathological and biochemical examination. Treatment with FE resulted in inhibition of CYP2E1 activity involved in the transformation of APAP in vivo. Expressions of the altered bile acid metabolism and transport-related genes and relative proteins of apoptosis were normalized by preconditioning with FE before APAP treatment. These results suggested FE to alleviate APAP-induced liver injury in a dose-dependent manner by inhibition of cytochrome P450 activity, hepatocyte apoptosis and regulation of bile acid homeostasis imbalance.

Safety and efficacy of sitagliptin in combination with transient continuous subcutaneous insulin infusion (CSII) therapy in patients with newly diagnosed type 2 diabetes.

Sitagliptin was used as monotherapy or in combination with metformin, thiazolidinedione or sulfonylurea. It is not clear whether effects are enhanced or unique when in combination with transient continuous subcutaneous insulin infusion (CSII) therapy. The aim of this study was to assess the safety and efficacy of sitagliptin in combination with transient CSII therapy in patients with newly diagnosed type 2 diabetes. Eighty patients with newly diagnosed type 2 diabetes from July 2011 to May 2013 were recruited into the study. These patients were randomly divided into a CSII monotherapy group (group A, n = 40) or a sitagliptin in combination with CSII therapy group (group B, n = 40) and received insulin intensive therapy. Treatments were maintained for 2 weeks. 75g oral glucose tolerance test (OGTT) was performed before and after treatments, and the levels of glucose, insulin and C-peptide were examined. The results indicated that, compared with CSII therapy group, the level of plasma glucose significantly decreased, the levels of insulin and C-peptide strikingly increased and homeostasis model assessment for beta-cell function (HOMA-ß) and Insulinogenic index (Ins index) were improved in the group of sitagliptin in combination with CSII therapy. Above all, the incidence of hypoglycemia was lower, insulin doses were less and the rate of recovery to normal glucose tolerance (NGT) or impaired glucose tolerance (IGT) determined by 75gOGTT was higher in the latter. So, Sitagliptin in combination with CSII therapy can be a new safe and effective therapy in patients with newly diagnosed type 2diabetes.

A mannitol-modified emodin nano-drug restores the intestinal barrier function and alleviates inflammation in a mouse model of DSS-induced ulcerative colitis.

BACKGROUND: Ulcerative colitis (UC) is an inflammatory disease of the colon that is characterized by mucosal ulcers. Given its increasing prevalence worldwide, it is imperative to develop safe and effective drugs for treating UC. Emodin, a natural anthraquinone derivative present in various medicinal herbs, has demonstrated therapeutic effects against UC. However, low bioavailability due to poor water solubility limits its clinical applications. METHODS: Emodin-borate nanoparticles (EmB) were synthesized to improve drug solubility, and they modified with oligomeric mannitol into microgels (EmB-MO) for targeted delivery to intestinal macrophages that express mannose receptors. UC was induced in a mouse model using dextran sulfate sodium (DSS), and different drug formulations were administered to the mice via drinking water. The levels of inflammation-related factors in the colon tissues and fecal matter were measured using enzyme-linked immunosorbent assay. Intestinal permeability was evaluated using fluorescein isothiocyanate dextran. HE staining, in vivo imaging, real-time PCR, and western blotting were performed to assess intestinal barrier dysfunction. RESULTS: Both EmB and EmB-MO markedly alleviated the symptoms of UC, including body weight loss, stool inconsistency, and bloody stools and restored the levels of pro- and anti-inflammatory cytokines. However, the therapeutic effects of EmB-MO on the macroscopic and immunological indices were stronger than those of EmB and similar to those of 5-aminosalicylic acid. Furthermore, EmB-MO selectively accumulated in the inflamed colon epithelium and restored the levels of the gut barrier proteins such as ZO-1 and Occludin. CONCLUSIONS: EmB-MO encapsulation significantly improved water solubility, which translated to greater therapeutic effects on the immune balance and gut barrier function in mice with DSS-induced UC. Our findings provide novel insights into developing emodin-derived drugs for the management of UC.

Effects of C-reactive protein on adipokines genes expression in 3T3-L1 adipocytes.

Adipose tissue is now recognized to be an important endocrine organ, secreting a variety of adipokines that are involved in the regulation of energy metabolism, insulin resistance and metabolic syndrome. C-reactive protein (CRP) is considered as one of the most sensitive markers of inflammation. A number of studies have shown that elevation of CRP concentrations is an independent predictive parameter of type 2 diabetes mellitus, which is also strongly associated with various components of the metabolic syndrome. The aim of the present study is to investigate the effects of CRP on adipokines genes expression in 3T3-L1 adipocytes. Quantitative real-time PCR analysis revealed that CRP inhibited adiponectin, leptin and peroxisome proliferator-activated receptor-gamma (PPAR-γ) genes expression and raised tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) mRNA levels in matured 3T3-L1 adipocytes in a dose and time-dependent manner. Pharmacological inhibition of phosphatidylinositol (PI)-3 kinase by wortmannin partially reversed the effects of CRP on adiponectin, TNF-α and leptin genes expression. These results collectively suggest that CRP regulates adiponectin, TNF-α, leptin, IL-6 and PPAR-γ genes expression, and that might represent a mechanism by which CRP regulates insulin resistance, obesity and metabolic syndrome.

Hyaluronic Acid-Melatonin Nanoparticles Improve the Dysregulated Intestinal Barrier, Microbiome and Immune Response in Mice with Dextran Sodium Sulfate-Induced Colitis.

Although the cause of inflammatory bowel disease (IBD) is unclear, current studies have found that the main factors involved in its pathogenesis include imbalance of mucosal immune response, intestinal dysbiosis, and destruction of the intestinal barrier. We synthesized an amphiphilic conjugate of hyaluronic acid (HA) and melatonin (MT), which have established immunomodulatory and antioxidant properties, by stimulating their nano-aggregation. Inducing colitis by dextran sodium sulfate (DSS), HA-MT accumulated in the inflamed colon epithelium of colitis mice, and markedly improved the colitis symptoms, repaired the damaged intestinal barrier and inhibited colon inflammation. In addition, through bacterial 16S rDNA sequencing, it was found that HA-MT can restore the ratio of Firmicutes/Bacteroidetes by increasing the overall microbial richness and diversity, and alleviate the intestinal dysbiosis of mice with colitis. In the analysis of the intestinal flora at the species level, the abundance of Lactobacillus increased in colitis mice treated with HA-MT while that of Bacteroides, Blautia and Streptococcus decreased in the colitis mice treated with HA-MT. Our findings suggest that the HA-MT system is a promising prebiotic, which can relieve the symptoms of IBD by regulating the intestinal microflora and restoring intestinal homeostasis, inhibiting inflammation.

Dihydromyricetin alleviates acetaminophen-induced liver injury via the regulation of transformation, lipid homeostasis, cell death and regeneration.

AIMS: We previously reported that Hovenia dulcis Thunb. extract, a traditional Chinese medicine rich in dihydromyricetin (DHM), exhibited a significant hepatoprotective effect against acetaminophen (APAP)-induced liver injury. However, whether DHM plays a protective role in APAP hepatotoxicity and what mechanisms are involved remain unclear. In this study, we evaluated the hepatoprotective effects of DHM against APAP-induced liver injury. MAIN METHODS: Male C57BL/6 mice were used for the experiment. LC-MS, q-PCR, immunochemistry and western blot analysis were employed to mechanism analysis. KEY FINDINGS: DHM exhibited a protective effect against APAP-induced liver injury. Further mechanistic investigations revealed that the protective effect of DHM against APAP hepatotoxicity had multi-target and multi-pathway characteristics involving APAP metabolism, lipid regulation, and hepatocyte death and regeneration. DHM pretreatment resulted in cytochrome P450 2E1 inhibition and UDP-glucuronosyltransferase 1A1 activation, affecting APAP biotransformation. Moreover, DHM pretreatment significantly ameliorated lipid dysregulation via peroxisome proliferator-activated receptor and sterol regulatory element-binding protein-1c (SREBP-1c) signalling pathways. Furthermore, DHM regulated the expression of cell death- and liver regeneration-associated proteins. SIGNIFICANCE: These results suggested that DHM alleviated APAP-induced liver injury in mice by inhibiting hepatocyte death, promoting p53-related regeneration, and regulating lipid homeostatic imbalance and APAP transformation. Based on these findings, DHM provides a potential and novel approach for preventing and treating APAP-induced liver damage, and SREBP-1c signalling might be a new therapeutic target for APAP hepatotoxicity.

Circulating adiponectin levels and the risk of breast cancer: a meta-analysis.

Adiponectin is an important adipokine exclusively secreted from adipose tissue. Growing evidence suggests that adiponectin inhibits the growth of cancer cells and reduces cancer risk. Many studies have examined the association between circulating adiponectin levels and the risk of breast cancer. However, the results of numerous epidemiological studies have been inconsistent. The aim of the present study was to conduct a systematic review and a meta-analysis on the association between circulating adiponectin levels and the risk of breast cancer. PubMed, MEDLINE, EMBASE, and ISI Web of Science were searched to identify all observational studies that examined the relationship between circulating adiponectin and breast cancer. Standard mean difference (SMD) values and 95% confidence intervals (CIs) were estimated and pooled using the meta-analysis methodology. Summary effect estimates were derived using a random effects meta-analysis model. The analysis included eight studies that met the study criteria and described the relationship between circulating adiponectin levels and breast cancer. A total of 1803 participants and 885 cases of breast cancer were included in this meta-analysis. Serum total adiponectin concentrations were lower in patients with breast cancer, with a pooled SMD of -0.39 µg/ml (95% CI -0.618 to -0.161, P=0.001). However, adiponectin levels were not associated with the risk of breast cancer in premenopausal women [four studies, random effects SMD=0.02 µg/ml (95% CI -0.164 to 0.204, P=0.829)]. These results collectively suggest that lower adiponectin levels are associated with a higher risk of breast cancer in postmenopausal women.

Serum lipids alterations in adenoid hypertrophy or adenotonsillar hypertrophy children with sleep disordered breathing.

OBJECTIVES: We aimed to investigate metabolic parameters in children with adenoid hypertrophy (AH) only or adenotonsillar hypertrophy (ATH) and compare them with healthy controls. METHODS: Forty-four prepubertal children aged 6-12 years who were obstructive symptoms and 16 healthy children were recruited in this study. All children underwent a complete otolaryngologic examination and sleep screening. The patients were divided into three groups according to obstruction type: normal, AH (adenoid grade III or IV, tonsil grade 1 or 2), and ATH (adenoid grade III or IV, tonsil grade 3 or 4). All participants underwent hematologic and biochemical tests including fasting blood glucose, insulin, and plasma lipids. RESULTS: (1) The children with AH and ATH had lower high-density lipoprotein cholesterol (HDL-C), when compared to normal children. (2) The level of HDL-C was negatively correlated with the sum of adenoid and tonsillar size scores and the apnea-hypopnea index (AHI) (r=-0.477, p<0.001 vs. r=-0.548, p<0.001, respectively). There was a modest association between HDL-C and minimal SpO2 (r=0.332, p=0.009). (3) Stepwise multiple regression analysis identified the AHI, triglycerides, and fasting insulin as independent predictors for HDL-C. CONCLUSIONS: Patients with adenoid and tonsil hypertrophy had low HDL-C. HDL-C levels are inversely related to the sum of adenoid and tonsillar size scores and AHI in SDB children. HDL-C may be a sensitive indicator of serum lipids changes in SDB children.