bims-faldev 2024-06-16 papers

Issue of 2024‒06‒16
six papers selected by
Stepheny Carneiro de Campos Zani, Universidade Estadual de Campinas

Genes Cells. 2024 Jun 12.

Antibiotic effects on gut microbiota modulate diet-induced metabolic dysfunction-associated steatohepatitis development in C57BL/6 mice.

Shun Takano, Koudai Kani, Kaichi Kasai, Naoya Igarashi, Miyuna Kato, Kana Goto, Yudai Matsuura, Mayuko Ichimura-Shimizu, Shiro Watanabe, Koichi Tsuneyama, Yukihiro Furusawa, Yoshinori Nagai.

The potential involvement of the gut microbiota in metabolic dysfunction-associated steatohepatitis (MASH) pathogenesis has garnered increasing attention. In this study, we elucidated the link between high-fat/cholesterol/cholate-based (iHFC)#2 diet-induced MASH progression and gut microbiota in C57BL/6 mice using antibiotic treatments. Treatment with vancomycin (VCM), which targets gram-positive bacteria, exacerbated the progression of liver damage, steatosis, and fibrosis in iHFC#2-fed C57BL/6 mice. The expression levels of inflammation- and fibrosis-related genes in the liver significantly increased after VCM treatment for 8 weeks. F4/80+ macrophage abundance increased in the livers of VCM-treated mice. These changes were rarely observed in the iHFC#2-fed C57BL/6 mice treated with metronidazole, which targets anaerobic bacteria. A16S rRNA sequence analysis revealed a significant decrease in α-diversity in VCM-treated mice compared with that in placebo-treated mice, with Bacteroidetes and Firmicutes significantly decreased, while Proteobacteria and Verrucomicrobia increased markedly. Finally, VCM treatment dramatically altered the level and balance of bile acid (BA) composition in iHFC#2-fed C57BL/6 mice. Thus, the VCM-mediated exacerbation of MASH progression depends on the interaction between the gut microbiota, BA metabolism, and inflammatory responses in the livers of iHFC#2-fed C57BL/6 mice.

Keywords: antibiotics; bile acid; fibrosis; gut microbiota; macrophage; metabolic dysfunction associated steatohepatitis

DOI: https://doi.org/10.1111/gtc.13134

Cell Metab. 2024 Jun 04. pii: S1550-4131(24)00184-0. [Epub ahead of print]

Reactive oxygen species regulation by NCF1 governs ferroptosis susceptibility of Kupffer cells to MASH.

Impaired self-renewal of Kupffer cells (KCs) leads to inflammation in metabolic dysfunction-associated steatohepatitis (MASH). Here, we identify neutrophil cytosolic factor 1 (NCF1) as a critical regulator of iron homeostasis in KCs. NCF1 is upregulated in liver macrophages and dendritic cells in humans with metabolic dysfunction-associated steatotic liver disease and in MASH mice. Macrophage NCF1, but not dendritic cell NCF1, triggers KC iron overload, ferroptosis, and monocyte-derived macrophage infiltration, thus aggravating MASH progression. Mechanistically, elevated oxidized phospholipids induced by macrophage NCF1 promote Toll-like receptor (TLR4)-dependent hepatocyte hepcidin production, leading to increased KC iron deposition and subsequent KC ferroptosis. Importantly, the human low-functional polymorphic variant NCF190H alleviates KC ferroptosis and MASH in mice. In conclusion, macrophage NCF1 impairs iron homeostasis in KCs by oxidizing phospholipids, triggering hepatocyte hepcidin release and KC ferroptosis in MASH, highlighting NCF1 as a therapeutic target for improving KC fate and limiting MASH progression.

Keywords: Kupffer cells; NCF1; ferroptosis; hepatocytes; iron deposition; lipid peroxidation; macrophages; metabolic dysfunction-associated steatohepatitis; oxidized phospholipids; reactive oxygen species

DOI: https://doi.org/10.1016/j.cmet.2024.05.008

Trends Pharmacol Sci. 2024 Jun 08. pii: S0165-6147(24)00096-8. [Epub ahead of print]

Implications of innate immune sexual dimorphism for MASLD pathogenesis and treatment.

Richell Booijink, Prakash Ramachandran, Ruchi Bansal.

Growing evidence suggests that metabolic dysfunction-associated steatotic liver disease (MASLD) is significantly higher in men versus women. Increased prevalence is observed in postmenopausal women, suggesting that age and sex (hormones) influence MASLD development and progression. Molecular data further reveal that sex regulates the innate immune responses with an essential role in MASLD progression. To date, there has been limited focus on the role of innate immune sexual dimorphism in MASLD, and differences between men and women are not considered in the current drug discovery landscape. In this review, we summarize the sex disparities and innate immune sexual dimorphism in MASLD pathogenesis. We further highlight the importance of harnessing sexual dimorphism in identifying therapeutic targets, developing pharmacological therapies, and designing (pre-) clinical studies for the personalized treatment for MASLD.

Keywords: innate immune system; metabolic dysfunction-associated steatotic liver disease (MASLD); myeloid cells; sex hormones; sexual dimorphism

DOI: https://doi.org/10.1016/j.tips.2024.05.004

J Hepatol. 2024 Jun 07. pii: S0168-8278(24)02303-1. [Epub ahead of print]

Efficacy, tolerability and pharmacokinetics of survodutide, a glucagon/glucagon-like peptide-1 receptor dual agonist, in cirrhosis.

NCT05296733 Investigators

BACKGROUND & AIMS: Survodutide is a glucagon/glucagon-like peptide-1 receptor dual agonist in development for treatment of metabolic dysfunction-associated steatohepatitis (MASH). We investigated survodutide in people with cirrhosis.METHODS: This multinational, non-randomized, open-label, phase 1 clinical trial initially evaluated a single subcutaneous (s.c.) dose of survodutide 0.3 mg in people with Child-Pugh class A, B or C cirrhosis and healthy individuals with or without overweight/obesity matched for age, sex, and weight; the primary endpoints were the area under the plasma concentration-time curve from 0 to infinity (AUC0-∞) and maximal plasma concentration (Cmax). Subsequently, people with overweight/obesity with or without cirrhosis and Child-Pugh class A or B received once-weekly s.c. doses escalated from 0.3 mg to 6.0 mg over 24 weeks then maintained for 4 weeks; the primary endpoint was drug-related treatment-emergent adverse events, with MASH/cirrhosis-related endpoints explored.
RESULTS: In the single-dose cohorts (n = 41), mean AUC0-∞ and Cmax were similar in those with cirrhosis compared with healthy individuals (90% confidence intervals for adjusted geometric mean ratios spanned 1). Drug-related adverse events occurred in 25.0% of healthy individuals and ≤25.0% of those with cirrhosis after single doses, and 82.4% and 87.5%, respectively, of the multiple-dose cohorts (n = 41) over 28 weeks. Liver fat content, liver stiffness, liver volume, body weight, and other hepatic and metabolic disease markers were generally reduced after 28 weeks of survodutide treatment.
CONCLUSIONS: Survodutide is generally tolerable in people with compensated or decompensated cirrhosis, does not require pharmacokinetic-related dose adjustment, and may improve liver-related non-invasive tests, supporting its investigation for MASH-related cirrhosis. Clinical trial number; ClinicalTrials.gov identifier: NCT05296733.
IMPACT AND IMPLICATIONS: Survodutide is a glucagon receptor/glucagon-like peptide-1 receptor dual agonist in development for treatment of metabolic dysfunction-associated steatohepatitis (MASH), which causes cirrhosis in ∼20% of cases. This trial delineates the pharmacokinetic and safety profile of survodutide in people with compensated or decompensated cirrhosis, and revealed associated reductions in liver fat content, markers of liver fibrosis and body weight. These findings have potential relevance for people with MASH-including those with decompensated cirrhosis, who are usually excluded from clinical trials of investigational drugs. Based on this study, further investigation of survodutide for MASH-related cirrhosis is warranted.

Keywords: glucagon; glucagon-like peptide-1; liver cirrhosis; metabolic diseases; non-alcoholic fatty liver disease

DOI: https://doi.org/10.1016/j.jhep.2024.06.003

Biomed Pharmacother. 2024 Jun 10. pii: S0753-3322(24)00772-8. [Epub ahead of print]176 116888

Chronic treatment with glucagon-like peptide-1 and glucagon receptor co-agonist causes weight loss-independent improvements in hepatic steatosis in mice with diet-induced obesity.

Emma Rose McGlone, David C D Hope, Iona Davies, Marian Dore, Rob Goldin, Ben Jones, Zhigang Liu, Jia V Li, Panagiotis A Vorkas, Bernard Khoo, David Carling, James Minnion, Stephen R Bloom, Tricia M-M Tan.

OBJECTIVES: Co-agonists at the glucagon-like peptide-1 and glucagon receptors (GLP1R/GCGR) show promise as treatments for metabolic dysfunction-associated steatotic liver disease (MASLD). Although most co-agonists to date have been heavily GLP1R-biased, glucagon directly acts on the liver to reduce fat content. The aims of this study were to investigate a GCGR-biased co-agonist as treatment for hepatic steatosis in mice.METHODS: Mice with diet-induced obesity (DIO) were treated with Dicretin, a GLP1/GCGR co-agonist with high potency at the GCGR, Semaglutide (GLP1R monoagonist) or food restriction over 24 days, such that their weight loss was matched. Hepatic steatosis, glucose tolerance, hepatic transcriptomics, metabolomics and lipidomics at the end of the study were compared with Vehicle-treated mice.
RESULTS: Dicretin lead to superior reduction of hepatic lipid content when compared to Semaglutide or equivalent weight loss by calorie restriction. Markers of glucose tolerance and insulin resistance improved in all treatment groups. Hepatic transcriptomic and metabolomic profiling demonstrated many changes that were unique to Dicretin-treated mice. These include some known targets of glucagon signaling and others with as yet unclear physiological significance.
CONCLUSIONS: Our study supports the development of GCGR-biased GLP1/GCGR co-agonists for treatment of MASLD and related conditions.

Keywords: Metabolic dysfunction-associated steatotic liver disease (MASLD); glucagon; glucagon-like peptide-1; non-alcoholic Fatty Liver Disease (NAFLD); type 2 diabetes mellitus; weight loss

DOI: https://doi.org/10.1016/j.biopha.2024.116888

Bio Protoc. 2024 Jun 05. 14(11): e5011

Isolation and Characterization of Extracellular Vesicles Derived from Ex Vivo Culture of Visceral Adipose Tissue.

Ankita Arora, Vinit Sharma, Rajesh Gupta, Anjali Aggarwal.

Extracellular vesicles (EVs) are a heterogeneous group of nanoparticles possessing a lipid bilayer membrane that plays a significant role in intercellular communication by transferring their cargoes, consisting of peptides, proteins, fatty acids, DNA, and RNA, to receiver cells. Isolation of EVs is cumbersome and time-consuming due to their nano size and the co-isolation of small molecules along with EVs. This is why current protocols for the isolation of EVs are unable to provide high purity. So far, studies have focused on EVs derived from cell supernatants or body fluids but are associated with a number of limitations. Cell lines with a high passage number cannot be considered as representative of the original cell type, and EVs isolated from those can present distinct properties and characteristics. Additionally, cultured cells only have a single cell type and do not possess any cellular interactions with other types of cells, which normally exist in the tissue microenvironment. Therefore, studies involving the direct EVs isolation from whole tissues can provide a better understanding of intercellular communication in vivo. This underscores the critical need to standardize and optimize protocols for isolating and characterizing EVs from tissues. We have developed a differential centrifugation-based technique to isolate and characterize EVs from whole adipose tissue, which can be potentially applied to other types of tissues. This may help us to better understand the role of EVs in the tissue microenvironment in both diseased and normal conditions. Key features • Isolation of tissue-derived extracellular vesicles from ex vivo culture of visceral adipose tissue or any whole tissue. • Microscopic visualization of extracellular vesicles' morphology without dehydration steps, with minimum effect on their shape. • Flow cytometry approach to characterize the extracellular vesicles using specific protein markers, as an alternative to the time-consuming western blot.

Keywords: Extracellular vesicles; Flow cytometry; Tissue-derived EVs; Transmission electron microscopy; Visceral adipose tissue; Western blotting

DOI: https://doi.org/10.21769/BioProtoc.5011