Mastiha (Pistacia lentiscus) Improves Gut Microbiota Diversity, Hepatic Steatosis, and Disease Activity in a Biopsy-Confirmed Mouse Model of Advanced Non-Alcoholic Steatohepatitis and Fibrosis

Dual RNA sequencing of Helicobacter pylori and host cell transcriptomes reveals ontologically distinct host-pathogen interaction

Helicobacter pylori is a highly successful pathogen that poses a substantial threat to human health. However, the dynamic interaction between H. pylori and the human gastric epithelium has not been fully investigated. In this study, using dual RNA sequencing technology, we characterized a cytotoxin-associated gene A (cagA)-modulated bacterial adaption strategy by enhancing the expression of ATP-binding cassette transporter-related genes, metQ and HP_0888, upon coculturing with human gastric epithelial cells. We observed a general repression of electron transport-associated genes by cagA, leading to the activation of oxidative phosphorylation. Temporal profiling of host mRNA signatures revealed the downregulation of multiple splicing regulators due to bacterial infection, resulting in aberrant pre-mRNA splicing of functional genes involved in the cell cycle process in response to H. pylori infection. Moreover, we demonstrated a protective effect of gastric H. pylori colonization against chronic dextran sulfate sodium (DSS)-induced colitis. Mechanistically, we identified a cluster of propionic and butyric acid-producing bacteria, Muribaculaceae, selectively enriched in the colons of H. pylori-pre-colonized mice, which may contribute to the restoration of intestinal barrier function damaged by DSS treatment. Collectively, this study presents the first dual-transcriptome analysis of H. pylori during its dynamic interaction with gastric epithelial cells and provides new insights into strategies through which H. pylori promotes infection and pathogenesis in the human gastric epithelium.

IMPORTANCE

Simultaneous profiling of the dynamic interaction between Helicobacter pylori and the human gastric epithelium represents a novel strategy for identifying regulatory responses that drive pathogenesis. This study presents the first dual-transcriptome analysis of H. pylori when cocultured with gastric epithelial cells, revealing a bacterial adaptation strategy and a general repression of electron transportation-associated genes, both of which were modulated by cytotoxin-associated gene A (cagA). Temporal profiling of host mRNA signatures dissected the aberrant pre-mRNA splicing of functional genes involved in the cell cycle process in response to H. pylori infection. We demonstrated a protective effect of gastric H. pylori colonization against chronic DSS-induced colitis through both in vitro and in vivo experiments. These findings significantly enhance our understanding of how H. pylori promotes infection and pathogenesis in the human gastric epithelium and provide evidence to identify targets for antimicrobial therapies.

Chemical characteristics and biological activity screening of Pistacia lentiscus mastic gum and leaves from Türkiye

BACKGROUND

Mastic gum is a resin that is produced by Pistacia lentiscus. It has many traditional uses, dating from ancient times, such as the treatment of gastrointestinal disorders and as a food additive. In this study, the leaves and mastic gum of trees of different ages from Karaburun and the Cesme peninsula in Türkiye were examined chemically and biologically. Flavonoids, and phenolic and fatty acid components were evaluated by a liquid chromatography system coupled with high resolution mass spectrometry (LC-HRMS) and gas chromatography with flame ionization detection (GC-FID). Cytotoxicity was screened against several cancer and healthy cell lines using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Inducible nitric oxide synthase (iNOS) inhibition was determined on lipopolysaccharide (LPS)-induced murine macrophage cell line (RAW 264.7) cells. Antiviral activity was measured against avian coronavirus using an in ovo virucidal antiviral activity assay.

RESULTS

The main phenolic constituents of the gum were found to be salicylic, rosmarinic, and caffeic acids whereas the most abundant compounds detected were flavonoids in the leaf extracts. The most abundant fatty acids in hexane extracts were palmitic and oleic acids. All gum extracts except 3-year-old gum had significant cytotoxic activity on HeLa (IC50 1.74 ± 0.03-4.76 ± 0.95) and PC-3 (0.64 ± 0.25-6.22 ± 1.40) cells. Moreover, reducing virus activity by fivefold or sixfold logarithmically between the range of 5-10 μg g-1 of 30-year-old gum extracts underscored the biological activity.

CONCLUSION

In ovo antiviral activity studies on the P. lentiscus were conducted for the first time. The mastic gum and leaves obtained from P. lentiscus may have strong potential in terms of their chemical content and antiviral and cytotoxic activity. As a consequence of these properties, it is a sustainable, renewable natural resource that can be used as an additive and flavoring in the food and pharmaceutical industries. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Pancreastatin deteriorates hepatic lipid metabolism via elevating fetuin B in ovariectomized rats

Hepatic steatosis is an important mstetabolic complication in women encountering postmenopausal phase of life. Pancreastatin (PST), has previously been investigated in diabetic and insulin resistant rodents. The present study highlighted the role of PST in ovariectomized rats. Female SD rats were ovariectomized and subsequently fed high fructose diet for 12 weeks. PST inhibitor peptide was intraperitoneally administered for 14 days and further examined for insulin resistance, glucose intolerance development, body mass composition, lipid profile detection and hepatic fibrosis. Gut microbial alterations has also been investigated. Results showed development of glucose intolerance in high fructose fed ovariectomized rats with reduced level of reproductive hormones including estradiol and progesterone. Enhanced lipid production was detected in these rats as they showed increased triglycerides, lipid accumulation in liver tissue (determined by HE staining, Oil Red O staining, Nile Red staining). Sirius Red and Masson's trichome analysis depicted positive results for fibrosis development. We also found gut microbiota alterations in fecal samples of these rats. Furthermore, PST inhibition decreased the expression of hepatic Fetuin B and resumed gut microbial diversity. PST deregulates hepatic lipid metabolism which leads to altered expression of Fetuin B in liver and gut dysbiosis in postmenopausal rats.

Commentary: When applying dietary therapies for gastrointestinal conditions, family values, culture, and social challenges matter

Some gastrointestinal conditions now have diet as a cornerstone to therapy. Three examples include the low-fermentable, oligosaccharide, disaccharide, monosaccharide, and polyol diet for irritable bowel syndrome, a gluten-free diet for celiac disease, and a hypoallergenic diet for eosinophilic esophagitis. All have been shown to be effective in Western or highly industrialized countries. However, these gastrointestinal conditions occur worldwide. Less is known regarding the effectiveness of dietary therapies in cultures and regions of dense religious and traditional practices where food is a central focus. This includes South Asia, the Mediterranean region, Africa, the Middle East, South America, and within Indigenous communities. Hence, there is a need to reproduce dietary intervention studies within cultures of dense traditional dietary practices to understand the applicability and acceptability of dietary therapy to establish generalizability. Furthermore, there is a need for nutrition experts to have a deep understanding of various cultural cuisines, practices, values, and customs. To achieve this, increasing the diversity of students in the sciences and having a diverse workforce of nutrition experts and health professionals that reflects the patient population will allow for more personalized care. In addition, there are social challenges, including a lack of medical insurance coverage, the cost of dietary interventions, and inconsistent nutrition messaging. Although there are many cultural considerations and social challenges to implementing effective dietary interventions around the world, these barriers are addressable through research methodologies that address culture and society challenges, and enhanced training of dietitians.

Antioxidant and anti-inflammatory agents in chronic liver diseases: Molecular mechanisms and therapy

Chronic liver disease (CLD) is a continuous process that causes a reduction of liver function lasting more than six months. CLD includes alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), chronic viral infection, and autoimmune hepatitis, which can lead to liver fibrosis, cirrhosis, and cancer. Liver inflammation and oxidative stress are commonly associated with the development and progression of CLD. Molecular signaling pathways such as AMP-activated protein kinase (AMPK), C-Jun N-terminal kinase, and peroxisome proliferator-activated receptors (PPARs) are implicated in the pathogenesis of CLD. Therefore, antioxidant and anti-inflammatory agents from natural products are new potent therapies for ALD, NAFLD, and hepatocellular carcinoma (HCC). In this review, we summarize some powerful products that can be potential applied in all the stages of CLD, from ALD/NAFLD to HCC. The selected agents such as β-sitosterol, curcumin, genistein, and silymarin can regulate the activation of several important molecules, including AMPK, Farnesoid X receptor, nuclear factor erythroid 2-related factor-2, PPARs, phosphatidylinositol-3-kinase, and lysyl oxidase-like proteins. In addition, clinical trials are undergoing to evaluate their efficacy and safety.

Masticadienonic acid from Chios mastic gum mitigates colitis in mice via modulating inflammatory response, gut barrier integrity and microbiota

BACKGROUND

Chios mastic gum (CMG) is a traditional Greek medicine used to treat a variety of gastrointestinal disorders, including inflammatory bowel disease (IBD). However, the bioactive compounds of CMG and the mechanisms of action for controlling of IBD remain unknown.

PURPOSE

Masticadienonic acid (MDA) is one of the most abundant constituents isolated from CMG. This study aims to investigate the potential effects and underlying mechanisms of MDA in the pathogenesis of colitis.

METHODS

The effects of MDA were evaluated using a dextran sulphate sodium (DSS)-induced acute colitis mouse model. The body and spleen weight and colon length and weight were measured and the clinical symptoms were analysed. Blood samples were collected to analyse the level of serum inflammatory markers. Colon tissues were processed for histopathological examination, evaluation of the epithelial barrier function, and investigation of the probable mechanisms of action. The gut microbiota composition was also studied to determine the mechanism for the beneficial effects of MDA on IBD.

RESULTS

MDA could ameliorate the severity of IBD by increasing the body weight and colon length, reducing spleen weight, disease activity index, and histological score. MDA treatments reduce the release of serum inflammatory cytokines tumour necrosis factor-alpha (TNFα), interleukin 1 beta (IL-1β), and interleukin 6 (IL-6) via inhibiting the MAPK and NF-κB signalling pathways. MDA supplementation could also improve the intestinal barrier function by activating the NF-E2-related factor-2 (Nrf2) signalling pathway and restoring the expression of tight junction proteins zonula occludens-1 (ZO-1) and occludin. In addition, MDA administration modulates the gut microbiota composition in DSS-induced colitis mice.

CONCLUSION

The results indicate that MDA attenuated experimental colitis by restoring intestinal barrier integrity, reducing inflammation, and modulating the gut microbiota. The present study provides novel insights into CMG-mediated remission of IBD and may facilitate the development of preventive and therapeutic strategies for IBD.

Design of Xenopus GLP-1-Based Long-Acting Dual GLP-1/Y2 Receptor Agonists

GLP-1 receptor (GLP-1R) and neuropeptide Y₂ receptor (Y₂R) dual agonists have shown great potential to treat obesity and type 2 diabetes (T2DM). We developed a multitarget strategy to design monomeric agonists based on Xenopus GLP-1 (xGLP-1) and PYY_3-36 analogues with dual activation activities on GLP-1R and Y₂R. A novel peptide, 6q, was obtained via stepwise structure optimization and in vitro receptor screens. In db/db and diet-induced obesity (DIO) mice, 6q produced greater effects on long-term glycemic control and body weight reduction than GLP-1R and Y₂R monoagonist counterparts. Notably, in high-fat diet-induced nonalcoholic steatohepatitis (NASH) mice, 6q treatment significantly reduced hepatic triglyceride and total cholesterol levels and reversed hepatic steatosis compared with GLP-1R monoagonist (liraglutide) treatment. Collectively, these data support the therapeutic potential of our GLP-1R/Y₂R dual agonist 6q as a novel antidiabetic, antiobesity, and antisteatotic agent.

Docosahexaenoic acid-rich fish oil alleviates hepatic steatosis in association with regulation of gut microbiome in ob/ob mice

It remains to study whether docosahexaenoic acid-rich fish oil (DHA-FO) improves hepatic lipid metabolism by leptin-independent mechanisms. We used ob/ob mice as a model to investigate the effects of DHA-FO on hepatic steatosis. DHA-FO inhibited lipid droplets (LD) formation in liver of ob/ob mice. Probably because DHA-FO consumption prevented the accumulation of oleic acid, and suppressed the synthesis of triglycerides and cholesteryl esters. These beneficial effects might be concerned with the promotion of short chain fatty acids (SCFAs) production. Furthermore, DHA-FO could reverse gut bacteria dysbiosis, including increasing the abundance of SCFAs producers (e.g. Akkermansia and unclassified_Muribaculaceae), and suppressing the proliferation of conditional pathogenic bacteria, such as unclassified_Lachnospiraceae. DHA-FO also promoted colonic microbial function ("Glycerolipid metabolism") associated with lipid metabolism. As a potential ingredient for functional food, DHA-FO reduced LD accumulation, which might be associated with modulation of obesity-linked gut microbiome in ob/ob mice.

A GLP-1/glucagon/CCK-2 receptors tri-agonist provides new therapy for obesity and diabetes

BACKGROUND AND PURPOSE

Glucagon-like peptide-1 receptor (GLP-1R) and glucagon receptor (GCGR) dual agonists have exerted promising therapeutic effects for the treatment of obesity and diabetes in clinical development. Moreover, GLP-1R and cholecystokinin 2 receptor (CCK-2R) dual agonists have been shown to restore pancreas function and improve glycemic control in many preclinical studies. In the present study, we describe for the first time that the beneficial effects of GLP-1R/GCGR and GLP-1R/CCK-2R dual agonists can be integrated into one peptide, resulting in significant anti-diabetes and anti-obesity effectiveness.

EXPERIMENTAL APPROACH

The in vitro potency of a novel GLP-1R/GCGR/CCK-2R tri-agonist (xGLP/GCG/gastrin) against GLP-1R, GCGR, CCK-1R and CCK-2R was determined on cells expressing the corresponding receptors by cAMP accumulation or ERK1/2 phosphorylation assays. The in vivo anti-diabetes and anti-obesity effects of xGLP/GCG/gastrin were studied in both db/db and diet induced obesity (DIO) mice.

KEY RESULTS

xGLP/GCG/gastrin was a potent and selective GLP-1R, GCGR, and CCK-2R tri-agonist. In DIO mice, the metabolic benefits of xGLP-1/GCG/gastrin such as reduction of body weight and hepatic lipid contents were significantly better than those of ZP3022 (GLP-1R/CCK-2R dual agonist) and liraglutide. In the short term study in db/db mice, xGLP/GCG/gastrin treatment exerted considerable effects on increasing islet numbers, islet areas, and insulin content. In the long-term treatment study in db/db mice, xGLP-1/GCG/gastrin displayed a significantly sustained improvement in glucose tolerance and glucose control compared with those of liraglutide, ZP3022, cotadutide (GLP-1R/GCGR dual agonist), and xGLP/GCG-15.

CONCLUSIONS AND IMPLICATIONS

These results demonstrate the therapeutic promise of xGLP-1/GCG/gastrin for obesity and diabetes.

Nutraceuticals in the Modulation of the Intestinal Microbiota: Current Status and Future Directions

Pharmaceutical interest in the human intestinal microbiota has increased considerably, because of the increasing number of studies linking the human intestinal microbial ecology to an increasing number of non-communicable diseases. Many efforts at modulating the gut microbiota have been made using probiotics, prebiotics and recently postbiotics. However, there are other, still little-explored opportunities from a pharmaceutical point of view, which appear promising to obtain modifications of the microbiota structure and functions. This review summarizes all in vitro, in vivo and clinical studies demonstrating the possibility to positively modulate the intestinal microbiota by using probiotics, prebiotics, postbiotics, essential oils, fungus and officinal plants. For the future, clinical studies investigating the ability to impact the intestinal microbiota especially by using fungus, officinal and aromatic plants or their extracts are required. This knowledge could lead to effective microbiome modulations that might support the pharmacological therapy of most non-communicable diseases in a near future.

Overview of Chios Mastic Gum (Pistacia lentiscus) Effects on Human Health

Despite the remarkable development of the medical industry in the current era, herbal products with therapeutic potentials arise as attractive alternative treatments. Consequently, Chios mastiha, a natural, aromatic resin obtained from the trunk and brunches of the mastic tree, has recently gained increasing scientific interest due to its multiple beneficial actions. Chios mastiha is being exclusively produced on the southern part of Chios, a Greek island situated in the northern Aegean Sea, and its therapeutic properties have been known since Greek antiquity. There is now substantial evidence to suggest that mastiha demonstrates a plethora of favorable effects, mainly attributed to the anti-inflammatory and anti-oxidative properties of its components. The main use of mastiha nowadays, however, is for the production of natural chewing gum, although an approval by the European Medicines Agency for mild dyspeptic disorders and for inflammations of the skin has been given. The aim of this article is to summarize the most important data about the therapeutic actions of Chios mastiha and discuss future fields for its medical application.

Impact of Genetic Polymorphism on Response to Therapy in Non-Alcoholic Fatty Liver Disease

In the last decades, the global prevalence of non-alcoholic fatty liver disease (NAFLD) has reached pandemic proportions with derived major health and socioeconomic consequences; this tendency is expected to be further aggravated in the coming years. Obesity, insulin resistance/type 2 diabetes mellitus, sedentary lifestyle, increased caloric intake and genetic predisposition constitute the main risk factors associated with the development and progression of the disease. Importantly, the interaction between the inherited genetic background and some unhealthy dietary patterns has been postulated to have an essential role in the pathogenesis of NAFLD. Weight loss through lifestyle modifications is considered the cornerstone of the treatment for NAFLD and the inter-individual variability in the response to some dietary approaches may be conditioned by the presence of different single nucleotide polymorphisms. In this review, we summarize the current evidence on the influence of the association between genetic susceptibility and dietary habits in NAFLD pathophysiology, as well as the role of gene polymorphism in the response to lifestyle interventions and the potential interaction between nutritional genomics and other emerging therapies for NAFLD, such as bariatric surgery and several pharmacologic agents.

Nutrigenetic Interactions Might Modulate the Antioxidant and Anti-Inflammatory Status in Mastiha-Supplemented Patients With NAFLD

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease with no therapeutic consensus. Oxidation and inflammation are hallmarks in the progression of this complex disease, which also involves interactions between the genetic background and the environment. Mastiha is a natural nutritional supplement known to possess antioxidant and anti-inflammatory properties. This study investigated how a 6-month Mastiha supplementation (2.1 g/day) could impact the antioxidant and inflammatory status of patients with NAFLD, and whether genetic variants significantly mediate these effects. We recruited 98 patients with obesity (BMI ≥ 30 kg/m²) and NAFLD and randomly allocated them to either the Mastiha or the placebo group for 6 months. The anti-oxidative and inflammatory status was assessed at baseline and post-treatment. Genome-wide genetic data was also obtained from all participants, to investigate gene-by-Mastiha interactions. NAFLD patients with severe obesity (BMI > 35kg/m²) taking the Mastiha had significantly higher total antioxidant status (TAS) compared to the corresponding placebo group (P value=0.008). We did not observe any other significant change in the investigated biomarkers as a result of Mastiha supplementation alone. We identified several novel gene-by-Mastiha interaction associations with levels of cytokines and antioxidant biomarkers. Some of the identified genetic loci are implicated in the pathological pathways of NAFLD, including the lanosterol synthase gene (LSS) associated with glutathione peroxidase activity (Gpx) levels, the mitochondrial pyruvate carrier-1 gene (MPC1) and the sphingolipid transporter-1 gene (SPNS1) associated with hemoglobin levels, the transforming growth factor‐beta‐induced gene (TGFBI) and the micro-RNA 129-1 (MIR129-1) associated with IL-6 and the granzyme B gene (GZMB) associated with IL-10 levels. Within the MAST4HEALTH randomized clinical trial (NCT03135873, www.clinicaltrials.gov) Mastiha supplementation improved the TAS levels among NAFLD patients with severe obesity. We identified several novel genome-wide significant nutrigenetic interactions, influencing the antioxidant and inflammatory status in NAFLD.

Activation of thyroid hormone receptor-β improved disease activity and metabolism independent of body weight in a mouse model of non-alcoholic steatohepatitis and fibrosis

BACKGROUND AND PURPOSE

Activation of hepatic thyroid hormone receptor β (THR-β) is associated with systemic lipid lowering, increased bile acid synthesis, and fat oxidation. In patients with non-alcoholic steatohepatitis (NASH), treatment with THR-β agonists decreased hepatic steatosis and circulating lipids, and induced resolution of NASH. We chose resmetirom (MGL-3196), a liver-directed, selective THR-β agonist, as a prototype to investigate the effects of THR-β activation in mice with diet-induced obesity (DIO) and biopsy-confirmed advanced NASH with fibrosis.

EXPERIMENTAL APPROACH

C57Bl/6J mice were fed a diet high in fat, fructose, and cholesterol for 34 weeks, and only biopsy-confirmed DIO-NASH mice with fibrosis were included. Resmetirom was administered at a daily dose of 3 mg·kg^-1 p.o., for 8 weeks. Systemic and hepatic metabolic parameters, histological non-alcoholic fatty liver disease (NAFLD) activity and fibrosis scores, and liver RNA expression profiles were determined to assess the effect of THR-β activation.

KEY RESULTS

Treatment with resmetirom did not influence body weight but led to significant reduction in liver weight, hepatic steatosis, plasma alanine aminotransferase activity, liver and plasma cholesterol, and blood glucose. These metabolic effects translated into significant improvement in NAFLD activity score. Moreover, a lower content of α-smooth muscle actin and down-regulation of genes involved in fibrogenesis indicated a decrease in hepatic fibrosis.

CONCLUSION AND IMPLICATIONS

Our model robustly reflected clinical observations of body weight-independent improvements in systemic and hepatic metabolism including anti-steatotic activity.

Hepatic steatosis integrated approach: nutritional guidelines and joined nutraceutical administration

BACKGROUND

The nonalcoholic fat liver disease (NAFLD) progresses in 30% of the patients to not alcoholic steatohepatitis (NASH) and subsequently in liver fibrosis and even primary cancer and death. Due to the complex physiopathology of the liver steatosis, NASH is an area orphan of specific drugs, but many authors suggest an integrated treatment based upon diet, lifestyle change, and pharmacology.

METHODS

Our clinical study selected from a wider patient cohort, 13 subjects, appealing to the Second Opinion Medical Consulting Network, for liver and nutritional problems. The diet was integrated with regular prescription of an herbal derivative based on Chrysanthellum americanum and Pistacia lentiscus L. extracts. Clinical data of the recruited patients including body weight, Body Mass Index, were recorded before and after treatment. Each patient underwent pre-post accurate clinical examination and lab exams. The liver stiffness and liver steatosis were evaluated by a trained hepatologist with FibroScan^®.

RESULTS

A significant reduction of anthropometric parameters was detected in all the patients at the end of the study; liver fibrosis and steatosis were instrumentally decreased in 8 subjects, but not significant changes in lab exams and no adverse effects were reported.

CONCLUSIONS

Chrysanthellum americanum and Pistacia lentiscus L. extracts were absolutely safe and effective and gave a substantial contribution to the life quality benefit, metabolic balance and gut function in patients with hepatic steatosis.

Triantennary GalNAc Molecular Imaging Probes for Monitoring Hepatocyte Function in a Rat Model of Nonalcoholic Steatohepatitis

Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease that can lead to irreversible liver cirrhosis and cancer. Early diagnosis of NASH is vital to detect disease before it becomes life-threatening, yet noninvasively differentiating NASH from simple steatosis is challenging. Herein, bifunctional probes have been developed that target the hepatocyte-specific asialoglycoprotein receptor (ASGPR), the expression of which decreases during NASH progression. The results show that the probes allow longitudinal, noninvasive monitoring of ASGPR levels by positron emission tomography in the newly developed rat model of NASH. The probes open new possibilities for research into early diagnosis of NASH and development of drugs to slow or reverse its progression.

Integrated omics analysis unraveled the microbiome-mediated effects of Yijin-Tang on hepatosteatosis and insulin resistance in obese mouse

BACKGROUND

Gut microbiota play important roles in insulin homeostasis and the pathogenesis of non-alcoholic fatty liver diseases (NAFLD). Yijin-Tang (YJT), a traditional Korean and Chinese medicine, is used in the treatment of gastrointestinal diseases and obesity-related disorders such as insulin resistance (IR) and NAFLD.

PURPOSE

Our aim was to identify the microbiome-mediated effects of YJT on IR and associated NAFLD by integrating metagenomics and hepatic lipid profile.

METHODS

C57BL/6J mice were fed a normal chow diet (NC) or high-fat/high-cholesterol (HFHC) diet with or without YJT treatment. Hepatic lipid profiles were analyzed using liquid chromatography/mass spectrometry, and the composition of gut microbiota was investigated using 16S rRNA sequencing. Then, hepatic lipid profiles, gut microbiome, and inflammatory marker data were integrated using multivariate analysis and bioinformatics tools.

RESULTS

YJT improved NAFLD, and 39 hepatic lipid metabolites were altered by YJT in a dose-dependent manner. YJT also altered the gut microbiome composition in HFHC-fed mice. In particular, Faecalibaculum rodentium and Bacteroides acidifaciens were altered by YJT in a dose-dependent manner. Also, we found significant correlation among hepatic phosphatidylglycerol metabolites, F. rodentium, and γδ-T cells. Moreover, interleukin (IL)-17, which is secreted by the γδ-T cell when it recognizes lipid antigens, were elevated in HFHC mice and decreased by YJT treatment. In addition, YJT increased the relative abundance of B. acidifaciens in NC or HFHC-fed mice, which is a gut microbiota that mediates anti-obesity and anti-diabetic effects by modulating the gut environment. We also confirmed that YJT ameliorated the gut tight junctions and increased short chain fatty acid (SCFA) levels in the intestine, which resulted in improved IR.

CONCLUSION

These data demonstrated that gut microbiome and hepatic lipid profiles are regulated by YJT, which improved the IR and NAFLD in mice with diet-induced obesity.

The Gut Microbiota and Its Metabolites, Novel Targets for Treating and Preventing Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent metabolic disorders worldwide, along with obesity and type 2 diabetes. NAFLD involves a series of liver abnormalities from simple hepatic steatosis to non-alcoholic steatohepatitis, which can ultimately lead to liver cirrhosis and cancer. The gut-liver axis plays an important role in the development of NAFLD, which depends mainly on regulation of the gut microbiota and its bacterial products. These intestinal bacterial species and their metabolites, including bile acids, tryptophan catabolites, and branched-chain amino acids, regulate adipose tissue and intestinal homeostasis and contribute to the pathogenesis of NAFLD/non-alcoholic steatohepatitis. In this review, the current evidence regarding the key role of the gut microbiota and its metabolites in the pathogenesis and development of NAFLD is highlighted, and the advances in the progression and applied prospects of gut microbiota-targeted dietary and exercise therapies is also discussed.

Incretin combination therapy for the treatment of non-alcoholic steatohepatitis

AIMS

To test specific mono-agonists to the glucagon-like peptide-1 receptor (GLP-1R), glucagon receptor (GCGR) and glucose-dependent insulinotropic peptide receptor (GIPR), individually and in combination, in a mouse model of diet-induced non-alcoholic steatohepatitis (NASH) and fibrosis in order to decipher the contribution of their activities and potential additive effects to improving systemic and hepatic metabolism.

MATERIALS AND METHODS

We induced NASH by pre-feeding C57BL/6J mice a diet rich in fat, fructose and cholesterol for 36 weeks. This was followed by 8 weeks of treatment with the receptor-specific agonists 1-GCG (20 μg/kg twice daily), 2-GLP1 (3 μg/kg twice daily) or 3-GIP (30 μg/kg twice daily), or the dual (1 + 2) or triple (1 + 2 + 3) combinations thereof. A dual GLP-1R/GCGR agonistic peptide, 4-dual-GLP1/GCGR (30 μg/kg twice daily), and liraglutide (100 μg/kg twice daily) were included as references.

RESULTS

Whereas low-dose 1-GCG or 3-GIP alone did not influence body weight, liver lipids and histology, their combination with 2-GLP1 provided additional weight loss, reduction in liver triglycerides and improvement in histological disease activity score. Notably, 4-dual-GLP-1R/GCGR and the triple combination of selective mono-agonists led to a significantly stronger reduction in the histological non-alcoholic fatty liver disease activity score compared to high-dose liraglutide, at the same extent of body weight loss.

CONCLUSIONS

GCGR and GIPR agonism provide additional, body weight-independent improvements on top of GLP-1R agonism in a murine model of manifest NASH with fibrosis.

Mastiha (Pistacia lentiscus) Improves Gut Microbiota Diversity, Hepatic Steatosis, and Disease Activity in a Biopsy-Confirmed Mouse Model of Advanced Non-Alcoholic Steatohepatitis and Fibrosis

SCOPE

As a result of the obesity epidemic, the prevalence of non-alcoholic steatohepatitis (NASH) is increasing. No drug is approved for the treatment of NASH. In this study, the effect of a nutritional supplement, Mastiha or Chios mastic gum, on metabolic and histological parameters and on the gut microbiome in mice with NASH and fibrosis was investigated.

METHODS AND RESULTS

Advanced NASH was induced by feeding C57BL/6J mice a diet rich in fat, sucrose, and cholesterol for 41 weeks. After randomization, animals received the NASH-inducing diet with or without 0.2% (w/w) Mastiha for a further 8 weeks. Disease activity was assessed by liver histology and determination of plasma transaminase activities. Fecal microbiota DNA extraction and 16S rRNA amplicon sequencing were used to determine the composition of the gut microbiome. Mastiha supplementation led to a significant reduction in circulating alanine aminotransferase (ALT) activity, improvement in hepatic steatosis and collagen content, and a reduction in NAFLD activity score. Furthermore, it resulted in a partial but significant recovery of gut microbiota diversity and changes in identity and abundance of specific taxa.

CONCLUSION

This is the first study demonstrating an improvement in disease activity in mice with advanced NASH with fibrosis by a diet containing Mastiha.