A long-term high-fat diet (HFD) exerts lipotoxic effects on multiple organs, particularly the liver, leading to metabolic diseases. This study aimed to delineate the dynamic effects of HFD on lipid metabolism, elucidate the mechanisms underlying hepatic lipotoxicity, and investigate the protective effects of Ganoderma lucidum against lipotoxicity both in vitro and in vivo.

C57BL/6 mice were fed either a 45% or 60% HFD, followed by measurements of body composition, serum lipid profile, and liver pathology at four, eight, twelve, and sixteen weeks. Inflammatory responses, the unfolded protein response (UPR), and endoplasmic reticulum (ER)-phagy were examined in the livers of mice at 16 weeks. Male C57BL/6 mice were randomly assigned to four groups (n = 12 per group): normal diet, 45% HFD, and two HFD + Ganoderma lucidum water extract (GLE) groups (1 g/kg/d and 2 g/kg/d of crude drug, orally administered by gavage for eight weeks following a four-week HFD induction).

Body weight, body fat, serum lipids, and hepatic steatosis increased progressively, accompanied by impaired glucose tolerance and liver injury, as indicated by elevated serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. HFD also induced activation of the STING and NF-κB signaling pathways, as well as the PERK and IRE1 branches of the UPR. Similarly, ER-phagy selective receptors, particularly FAM134B, which is primarily expressed in hepatocytes as shown by single-cell sequencing, were upregulated after 16 weeks of HFD feeding. Furthermore, GLE mitigated palmitic acid-induced lipotoxicity in primary hepatocytes, as evidenced by improved cell viability, reduced ALT, AST, and lactate dehydrogenase levels in the culture supernatant, and decreased transferase dUTP nick-end labeling-positive cell counts. In 45% HFD-fed mice, GLE reduced serum total cholesterol, low-density lipoprotein, and hepatic triglyceride levels.

HFD-induced lipotoxicity causes hepatic tissue injury and inflammatory responses, which may be alleviated by coordinated regulation of compensatory UPR and ER-phagy. Ganoderma lucidum shows promise as a dietary supplement for managing metabolic disorders.

Acute-on-chronic liver failure (ACLF) is a life-threatening syndrome characterized by systemic inflammation and immune dysregulation, in which macrophages play a key role in organ injury. This study aimed to investigate the role and mechanism of pyruvate dehydrogenase kinase 4 (PDK4) in ACLF to identify therapeutic targets that modulate macrophage function and mitigate ACLF progression.

Single-cell RNA sequencing data from healthy and ACLF liver tissues were analyzed from the Sequence Read Archive database. Transcriptomic data of peripheral blood mononuclear cells from ACLF patients (GSE168048) were also examined. In vitro experiments assessed PDK4 expression and macrophage polarization, and conditioned-medium studies evaluated effects on LO2 hepatocytes. In vivo validation was performed in ACLF mouse models treated with a PDK4 inhibitor.

Single-cell analysis revealed a predominance of M1-polarized hepatic macrophages in ACLF with marked upregulation of PDK4. Peripheral blood mononuclear cell transcriptomics showed that higher PDK4 expression correlated with 28-day mortality. In vitro, PDK4 expression increased in M1 macrophages; PDK4 inhibition attenuated M1 polarization and reduced cytotoxic effects on LO2 cells. In vivo, pharmacologic inhibition of PDK4 suppressed M1 polarization in macrophages, alleviated liver inflammation, and reduced tissue injury. Mechanistically, PDK4 promoted M1 polarization via activation of signal transducer and activator of transcription 1 signaling.

PDK4 is a key pro-inflammatory regulator in ACLF by promoting M1 macrophage polarization. Targeting PDK4 may be a promising strategy to attenuate inflammation and improve clinical outcomes in ACLF.

Sterol regulatory element-binding protein 1 (SREBP1), a key regulator of lipogenesis, is highly expressed in tumors, but the mechanisms sustaining its elevated levels remain unclear. The role of UFMylation, a posttranslational modification, in modulating SREBP1 stability and tumor progression has not been explored. This study aimed to investigate the role of UFMylation in the progression of liver cancer.

Liquid chromatography-tandem mass spectrometry was employed to investigate the interacting proteins of ubiquitin-fold modifier 1-specific ligase 1 (UFL1). Knockdown of UFL1 and DDRGK domain-containing protein 1 (DDRGK1) was performed to assess SREBP1 stability. In vitro and in vivo models of hepatocellular carcinoma (HCC) were used to evaluate tumor progression. Clinical correlations between UFL1/DDRGK1 and SREBP1 levels were analyzed in HCC patient samples.

SREBP1 undergoes UFMylation, which synergizes with ubiquitination to reduce its stability. Depletion of UFL1 or DDRGK1 increased SREBP1 stability, driving HCC progression. Clinically, UFL1 and DDRGK1 levels were reduced in HCC tissues and inversely correlated with SREBP1 expression. Fatostatin (an SREBP1 inhibitor) enhanced the therapeutic effect of Lenvatinib in HCC models with low UFL1 expression.

UFMylation is a critical posttranslational modification that destabilizes SREBP1, and its dysregulation contributes to HCC progression. Targeting the UFMylation-SREBP1 axis, particularly through Fatostatin and Lenvatinib combination therapy, represents a novel therapeutic strategy for HCC.

Dysphagia, a severe comorbidity of many neurological diseases, often lacks targeted therapies. Electrical stimulation of cranial nerves represents a novel therapeutic class. This critical review assessed the clinical effectiveness and safety of various approaches for electrical stimulation of the cranial nerves for treating dysphagia, categorized as implantable (directly targeting the nerve), minimally invasive (pharyngeal electrical stimulation), and non-invasive (transcutaneous). A critical literature review was conducted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The PubMed database was comprehensively searched, and studies were rigorously assessed for inclusion and exclusion criteria. The Newcastle–Ottawa Scale was used to assess the risk of bias. The analysis included 15 clinical studies: four assessing vagus nerve stimulation (including implantable and transcutaneous approaches) and eleven assessing pharyngeal electrical stimulation. Most evaluated studies, particularly for pharyngeal electrical stimulation and transcutaneous vagus nerve stimulation, demonstrated significant beneficial effects on validated dysphagia outcome measures. Importantly, no long-term severe adverse effects were reported across the evaluated stimulation approaches. Cumulative evidence indicates that vagus nerve stimulation and pharyngeal electrical stimulation approaches can effectively alleviate dysphagia symptoms. The different stimulation approaches appear to be complementary, with distinct profiles rendering them suitable for different therapeutic contexts (e.g., short-term hospital-based vs. long-term at-home treatment). Consequently, they represent distinct and valuable options for individualized dysphagia therapy.

Hepatic metastasis (HM) and lymph node metastasis in pancreatic ductal adenocarcinoma (PDAC) are associated with worse overall survival, largely due to the immunosuppressive microenvironment. However, the key immunosuppressive cells within this microenvironment remain inadequately defined. This study aimed to identify the cells contributing to HM and lymph node metastasis in PDAC and to investigate their regulatory mechanisms.

Single-cell RNA sequencing was used to profile the tumor microenvironment in HM, lymph node-negative, and lymph node-positive (LNP) PDAC tissues. Bioinformatic analyses revealed subtypes of immunosuppressive myeloid-derived suppressor cells (MDSCs). Immunofluorescence and flow cytometry were performed to detect the distribution and proportion of interleukin-1 receptor antagonist (IL1RA+) MDSCs. The immunosuppressive and pro-tumorigenic functions of IL1RA+ MDSCs were analyzed using enzyme-linked immunosorbent assay, quantitative reverse transcription polymerase chain reaction, Western blotting, and Transwell assays. Patient-derived xenograft mouse models were employed to validate the role of IL1RA+ MDSCs in vivo.

Polymorphonuclear-MDSCs were found to be recruited to metastatic PDAC tissues. Among these, IL1RA+ MDSCs were enriched in HM/LNP tissues and correlated with poorer prognosis. IL1RA+ MDSCs promoted M2 macrophage polarization and suppressed the activity of natural killer cells and cytotoxic T cells. Furthermore, IL1RA+ MDSCs accelerated PDAC migration and progression by upregulating epithelial–mesenchymal transition-related proteins in both in vitro and in vivo models.

IL1RA+ MDSCs represent a key immunosuppressive and pro-tumorigenic subtype in HM/LNP PDAC, providing a solid theoretical basis for prognostic prediction and the development of immunotherapeutic strategies targeting these cells in HM/LNP PDAC.

As the leading cause of chronic liver disease globally, metabolic dysfunction-associated steatotic liver disease (MASLD) lacks effective therapies. This study aimed to investigate the therapeutic potential and molecular mechanisms of oxytocin (OXT) in MASLD.

Integrated bioinformatics analysis of MASLD datasets was carried out to identify OXT-related metabolic disturbances. Serum OXT levels were quantified using an enzyme-linked immunosorbent assay in 113 MASLD patients and 63 healthy controls. Mechanistic assays were conducted using oleic acid (OA)-induced, lipid-loaded HepG2 cells and high-fat diet-fed C57BL/6 mice, and OXT was administered intraperitoneally in vivo and supplemented in vitro.

Bioinformatics analysis revealed significant changes in OXT expression levels, particularly in fatty acid metabolism. Elevated OXT expression levels in MASLD patients were identified as an independent prognostic factor. In vitro, OXT significantly reduced OA-induced lipid accumulation in HepG2 cells, while in vivo, it decreased body weight, liver injury, and serum cholesterol levels in high-fat diet-fed mice. Mechanistically, OXT enhanced the expression level of phosphorylated AMP-activated protein kinase (AMPK) and suppressed the levels of sterol regulatory element-binding protein-1c (SREBP1c) and fatty acid synthase (FAS). Blockade of AMPK with the chemical inhibitor Compound C reversed the ability of OXT to suppress the SREBP1c/FAS axis and reduce lipid accumulation in hepatocytes. Additionally, OXT inhibited the nuclear translocation of SREBP1c in OA-treated cells.

The findings demonstrate that OXT may serve as a potential therapeutic agent for MASLD by regulating the AMPK/SREBP1c/FAS pathway in lipid metabolism.