Choline Deficiency

Growth differentiation factor 15 (GDF15) is an endocrine hormone belonging to the TGFβ superfamily member. GDF15 administration or GDF15 overexpression has been reported to have anti-obesity and anti-diabetic effects. Although non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) is frequently associated with obesity and insulin resistance, the functional role of endogenous GDF15 and therapeutic effect of GDF15 overexpression in NASH and related metabolic deterioration have not been evaluated. Here, we found that GDF15 expression was increased in the livers of NASH animal models and human subjects with NASH. Elevated expression of GDF15 was due to diet-induced hepatic endoplasmic reticulum (ER) stress. Gdf15-knockout mice exhibited aggravated NASH phenotypes such as increased steatosis, hepatic inflammation, fibrosis, liver injury, and metabolic deterioration. Furthermore, GDF15 directly suppressed expression of fibrosis-related genes and osteopontin (OPN), contributing factors for NASH-related fibrosis, in hepatic stellate cells in vitro and in the liver of mice in vivo. Finally, we found that GDF15-transgenic mice showed attenuation of NASH phenotypes and metabolic deterioration. Therefore, our results suggest that induction of endogenous GDF15 is a compensatory mechanism to protect against the progression of NASH and that GDF15 could be an attractive therapeutic candidate for treatment of NASH and NASH-related metabolic deterioration.

Hepatocellular carcinoma (HCC) is a common cancer worldwide and represents the outcome of the natural history of chronic liver disease. The growing rates of HCC may be partially attributable to increased numbers of people with non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). However, details of the liver-specific molecular mechanisms responsible for the NAFLD-NASH-HCC progression remain unclear, and mouse models that can be used to explore the exact factors that influence the progression of NAFLD/NASH to the more chronic stages of liver disease and subsequent HCC are not yet fully established. We have previously reported a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) as a dietary NASH model with rapidly progressive liver fibrosis in mice. The current study in C57BL/6J mice fed CDAHFD provided evidence for the chronic persistence of advanced hepatic fibrosis in NASH and disease progression towards HCC in a period of 36 weeks. When mice fed CDAHFD were switched back to a standard diet, hepatic steatosis was normalized and NAFLD activity score improved, but HCC incidence increased and the phenotype of fibrosis-associated HCC development was observed. Moreover, when mice continued to be fed CDAHFD for 60 weeks, HCC further developed without severe body weight loss or carcinogenesis in other organs. The autochthonous tumours showed a variety of histological features and architectural patterns including trabecular, pseudoglandular and solid growth. The CDAHFD mouse model might be a useful tool for studying the development of HCC from NAFLD/NASH, and potentially useful for better understanding pathological changes during hepatocarcinogenesis.

Receptor-interacting protein kinase 3 (RIPK3) mediates necroptosis, a form of programmed cell death that promotes inflammation in various pathological conditions, suggesting that it might be a privileged pharmacological target. However, its function in glucose homeostasis and obesity has been unknown. Here we show that RIPK3 is over expressed in the white adipose tissue (WAT) of obese mice fed with a choline-deficient high-fat diet. Genetic inactivation of Ripk3 promotes increased Caspase-8-dependent adipocyte apoptosis and WAT inflammation, associated with impaired insulin signalling in WAT as the basis for glucose intolerance. Similarly to mice, in visceral WAT of obese humans, RIPK3 is overexpressed and correlates with the body mass index and metabolic serum markers. Together, these findings provide evidence that RIPK3 in WAT maintains tissue homeostasis and suppresses inflammation and adipocyte apoptosis, suggesting that systemic targeting of necroptosis might be associated with the risk of promoting insulin resistance in obese patients.

Background: Choline is an essential nutrient crucial for liver function. It is required for bile and lipoprotein secretion and the synthesis of both phosphatidylcholine (PC) to ensure tissue homeostasis and betaine as a methyl donor. Choline deficiency has been implicated in the pathogenesis of intestinal failure-associated liver disease (IFALD), with the strongest evidence for its contribution to hepatic steatosis in patients with short bowel syndrome (SBS). Contributing factors are (1) an impaired recycling of choline from bile PC, leading to fecal choline losses; (2) small bowel bacterial overgrowth resulting in choline degradation prior to absorption; and (3) parenteral nutrition (PN) insufficient to meet choline requirements. However, data on choline status and its metabolites in pediatric patients with SBS are scarce. Objective: To investigate plasma levels of choline and choline-related metabolites in children with SBS and evaluate differences according to PN dependency and the presence of hepatic steatosis. Methods: Retrospective analysis of data from SBS patients managed at our intestinal rehabilitation program between March 2021 and July 2025. Target parameters in plasma samples were measured using tandem mass spectrometry. Statistical analysis and group comparison of laboratory and clinical data were performed. Results: A total of 127 samples from 80 children with SBS (0.2-17.9 years) were analyzed. Plasma choline, betaine, and PC concentrations were low, with 25% of patients showing markedly reduced choline and betaine levels below 6.4 µmol/L and 16 µmol/L, respectively. TMAO concentrations, indicating bacterial choline degradation, showed extreme variability (0-30 µmol; normal Conclusions: Patients with SBS, with and without PN, are at risk of choline and betaine deficiency, which is associated with IFALD-steatosis. Controlled trials on choline supplementation in pediatric patients with SBS are warranted.