Metabolism-associated fatty liver disease (MAFLD) is a multifaceted disease that involves complex interactions between various organs, including the gut and heart. It is defined by hepatic lipid ...accumulation and is related to metabolic dysfunction, obesity, and diabetes. Understanding the intricate interplay of the gut–liver–heart crosstalk is crucial for unraveling the complexities of MAFLD and developing effective treatment and prevention strategies. The gut–liver crosstalk participates in the regulation of the metabolic and inflammatory processes through host–microbiome interactions. Gut microbiota have been associated with the development and progression of MAFLD, and its dysbiosis contributes to insulin resistance, inflammation, and oxidative stress. Metabolites derived from the gut microbiota enter the systemic circulation and influence both the liver and heart, resulting in the gut–liver–heart axis playing an important role in MAFLD. Furthermore, growing evidence suggests that insulin resistance, endothelial dysfunction, and systemic inflammation in MAFLD may contribute to an increased risk of cardiovascular disease (CVD). Additionally, the dysregulation of lipid metabolism in MAFLD may also lead to cardiac dysfunction and heart failure. Overall, the crosstalk between the liver and heart involves a complex interplay of molecular pathways that contribute to the development of CVD in patients with MAFLD. This review emphasizes the current understanding of the gut–liver–heart crosstalk as a foundation for optimizing patient outcomes with MAFLD.
Introduction: Excessive alcohol intake often results in hangovers and inflammatory liver damage, posing a significant health concern. Current treatment options for hangovers are still insufficient, ...highlighting the urgent need for new therapeutic approaches. Psyllium fiber (PF) is well-known for its gastrointestinal benefits, but its effect on hangovers is less explored. Methods: We utilized a mouse model with a single binge drinking (4 g/kg) to induce hangover and inflammatory liver injury. Intestine and liver injury were serologically and histologically estimated. Hangover symptoms were assessed using cylinder and footprint tests to objectively quantify hangover symptoms in mice. Results: Binge drinking significantly activated alcohol-metabolizing enzymes in the small intestine and liver, leading to inflammatory damage. Concurrently, there was a rise in alcohol metabolites such as acetaldehyde and acetone, which exhibited a positive correlation with hangover symptoms in mice. Interestingly, the oral administration of PF (100 mg/kg) alongside alcohol consumption significantly reduced the activity of these enzymes and lowered the levels of alcohol metabolites. Mice treated with PF exhibited a considerable improvement in hangover symptoms and a reduction in hepatic inflammation, compared to control groups. Furthermore, in vitro experiments using HepG2 cell lines and semipermeable membranes demonstrated that PF effectively inhibits alcohol absorption into the body. Discussion: In conclusion, PF demonstrates a potential protective effect against alcohol-induced hangover and liver injury by inhibiting the absorption of alcohol and lowering hangover-related alcohol metabolites. This study suggests that PF could serve as an effective therapeutic option for mitigating the adverse effects of excessive alcohol consumption.
Background and Aims
Mitochondrial double‐stranded RNA (mtdsRNA) and its innate immune responses have been reported previously; however, mtdsRNA generation and its effects on alcohol‐associated liver ...disease (ALD) remain unclear. Here, we report that hepatic mtdsRNA stimulates toll‐like receptor 3 (TLR3) in Kupffer cells through the exosome (Exo) to enhance interleukin (IL)‐17A (IL‐17A) production in ALD.
Approach and Results
Following binge ethanol (EtOH) drinking, IL‐17A production primarily increased in γδ T cells of wild‐type (WT) mice, whereas the production of IL‐17A was mainly facilitated by CD4+ T cells in acute‐on‐chronic EtOH consumption. These were not observed in TLR3 knockout (KO) or Kupffer cell–depleted WT mice. The expression of polynucleotide phosphorylase, an mtdsRNA‐restricting enzyme, was significantly decreased in EtOH‐exposed livers and hepatocytes of WT mice. Immunostaining revealed that mtdsRNA colocalized with the mitochondria in EtOH‐treated hepatocytes from WT mice and healthy humans. Bioanalyzer analysis revealed that small‐sized RNAs were enriched in EtOH‐treated Exos (EtOH‐Exos) rather than EtOH‐treated microvesicles in hepatocytes of WT mice and humans. Quantitative real‐time PCR and RNA sequencing analyses indicated that mRNA expression of mitochondrial genes encoded by heavy and light strands was robustly increased in EtOH‐Exos from mice and humans. After direct treatment with EtOH‐Exos, IL‐1β expression was significantly increased in WT Kupffer cells but not in TLR3 KO Kupffer cells, augmenting IL‐17A production of γδ T cells in mice and humans.
Conclusions
EtOH‐mediated generation of mtdsRNA contributes to TLR3 activation in Kupffer cells through exosomal delivery. Consequently, increased IL‐1β expression in Kupffer cells triggers IL‐17A production in γδ T cells at the early stage that may accelerate IL‐17A expression in CD4+ T cells in the later stage of ALD. Therefore, mtdsRNA and TLR3 may function as therapeutic targets in ALD.
The concept of "intestinal drinking" in this study refers to the continued absorption of alcohol in the gastrointestinal tract until adequate defecation occurs.
A longitudinal observation of hangover ...symptoms and alcohol metabolites in healthy humans following binge drinking was conducted.
The hangover symptoms resulting from binge alcohol consumption were relieved by defecation. Following the defecation process, not only the blood ethanol levels, but also the concentrations of blood acetaldehyde, methanol, and iso-propanol, exhibited significant reductions.
This pilot study provides a different perspective for addressing hangovers and potentially mitigating the risks of alcoholic liver diseases.
Alcohol-associated liver disease (ALD) has become a major global concern, but the development of effective drugs remains a challenge despite numerous preclinical and clinical pieces of research on ...the effects of natural compounds. To address this, a meta-analysis was conducted on the efficacy of
for ALD based on preclinical studies. We identified 18 relevant studies from PubMed, Web of Science, and Cochrane Library database and evaluated their methodological quality using the Systematic Review Centre for Laboratory animal Experimentation tool. We analyzed the data using
,
-values, and fixed effects models to assess overall efficacy and heterogeneity. The results of the meta-analysis suggested that
treatment is effective in reducing the levels of inflammatory markers associated with hepatic injury caused by ALD in animal experiments. Additionally, the administration of
was found to down-regulate inflammatory cytokines and attenuate lipid metabolism in ALD. Moreover,
markedly improved the antioxidant systems in ALD. Therefore, we concluded that
has the potential to be a promising therapeutic agent for ALD. Further research is needed to confirm these findings and to determine the optimal dosage and duration of treatment for patients with ALD.
Although tremendous research has reported the protective effects of natural compounds in nonalcoholic fatty liver disease (NAFLD), there is still no approved drug. This study aimed to examine the ...efficacy of
in NAFLD in preclinical studies. A total of 41 studies were identified by searching the PubMed, Web of Science, and Cochrane Library databases. The methodological quality was assessed by the risk of bias tool from the Systematic Review Center for Laboratory Animal Experimentation. The standardized mean difference (SMD) with a 95% confidence interval was calculated, and the random effects model was used to examine overall efficacy or heterogeneity. The publication bias was analyzed by Egger's test. The results showed that
treatment significantly reduced the systemic levels of alanine aminotransferase (SMD: -2.15 IU/L;
< 0.0001), aspartate aminotransferase (SMD: -2.86 IU/L;
< 0.0001), triglyceride (SMD: -2.86 mg/dL;
< 0.0001), total cholesterol (SMD: -1.69 mg/dL;
< 0.0001), low-density lipoprotein (SMD: -1.46 mg/dL;
< 0.0001), and fasting glucose (SMD: -1.45 mg/dL;
< 0.0001) while increasing high-density lipoprotein (SMD: 1.22 mg/dL;
= 0.0002) in NAFLD regardless of animal models or species. These findings may suggest that
is a promising therapeutic agent for NAFLD treatment.
The continuous rise in the prevalence of nonalcoholic fatty liver disease (NAFLD) is emerging as a global health issue. Although the protective effects of N-acetylcysteine (NAC), an antioxidant, ...against various diseases have been reported, it is still unclear whether NAC has therapeutic potential in NAFLD. Thus, the present meta-analysis aimed to investigate the efficacy of NAC on NAFLD in preclinical studies.
By searching PubMed, Web of Science, and Cochrane Library, 13 studies were included. The methodological quality was assessed based on the SYstematic Review Centre for Laboratory animal Experimentation guideline, and heterogeneity was evaluated with
and
values. Publication bias was assessed by Egger's test and sensitivity analysis was performed.
The results showed that NAC treatment significantly improved systemic and hepatic lipid metabolism (
< 0.01), inflammation-related liver injury (
< 0.01), glucose intolerance (
< 0.05), and hepatic steatosis (
< 0.01) by restoring hepatic glutathione (GSH) (
< 0.05) and GSH reductase (
< 0.05) levels compared to controls in NAFLD-induced animals. Consistently, in bulk, single-cell, and spatial transcriptomics data, the abovementioned target pathways of NAC were strongly associated with NAFLD development in mice and patients.
Our study suggests that NAC has therapeutic potential for NAFLD and should be considered for future clinical trials.
Obesity-mediated hypoxic stress underlies inflammation, including interferon (IFN)-γ production by natural killer (NK) cells in white adipose tissue. However, the effects of obesity on NK cell IFN-γ ...production remain obscure. Here, we show that hypoxia promotes xCT-mediated glutamate excretion and C-X-C motif chemokine ligand 12 (CXCL12) expression in white adipocytes, resulting in CXCR4+ NK cell recruitment. Interestingly, this spatial proximity between adipocytes and NK cells induces IFN-γ production in NK cells by stimulating metabotropic glutamate receptor 5 (mGluR5). IFN-γ then triggers inflammatory activation of macrophages and augments xCT and CXCL12 expression in adipocytes, forming a bidirectional pathway. Genetic or pharmacological inhibition of xCT, mGluR5, or IFN-γ receptor in adipocytes or NK cells alleviates obesity-related metabolic disorders in mice. Consistently, patients with obesity showed elevated levels of glutamate/mGluR5 and CXCL12/CXCR4 axes, suggesting that a bidirectional pathway between adipocytes and NK cells could be a viable therapeutic target in obesity-related metabolic disorders.
Display omitted
•Hypoxic adipocytes recruit NK cells through CXCL12 and excrete glutamate by xCT•mGluR5 activation in CXCR4+ NK cells exerts IFN-γ production and inflammation•NK cell-derived IFN-γ augments the glutamate and CXCL12 production by adipocytes•Bidirectional crosstalk between adipocytes and NK cells mediates obesity and NAFLD
Kim et al. show that hypoxia induces xCT-mediated glutamate excretion and CXCL12 expression in adipocytes, recruiting CXCR4+ NK cells. This spatial proximity provokes IFN-γ production by NK cells via mGluR5 activation, reinforcing glutamate and CXCL12 production by adipocytes. Consequently, this bidirectional interaction between adipocytes and NK cells instigates obesity.
Chronic alcohol consumption often induces hepatic steatosis but rarely causes severe inflammation in Kupffer cells (KCs) despite the increased hepatic influx of lipopolysaccharide (LPS), suggesting ...the presence of a veiled tolerance mechanism. In addition to LPS, the liver is affected by several gut-derived neurotransmitters through the portal blood, but the effects of catecholamines on KCs have not been clearly explored in alcohol-associated liver disease (ALD). Hence, we investigated the regulatory roles of catecholamine on inflammatory KCs under chronic alcohol exposure. We discovered that catecholamine levels were significantly elevated in the cecum, portal blood, and liver tissues of chronic ethanol-fed mice. Increased catecholamines induced mitochondrial translocation of cytochrome P450 2E1 in perivenous hepatocytes expressing the β2-adrenergic receptor (ADRB2), leading to the enhanced production of growth differentiation factor 15 (GDF15). Subsequently, GDF15 profoundly increased ADRB2 expression in adjacent inflammatory KCs to facilitate catecholamine/ADRB2-mediated apoptosis. Single-cell RNA sequencing of KCs confirmed the elevated expression of Adrb2 and apoptotic genes after chronic ethanol intake. Genetic ablation of Adrb2 or hepatic Gdf15 robustly decreased the number of apoptotic KCs near perivenous areas, exacerbating alcohol-associated inflammation. Consistently, we found that blood and stool catecholamine levels and perivenous GDF15 expression were increased in patients with early-stage ALD along with an increase in apoptotic KCs. Our findings reveal a novel protective mechanism against ALD, in which the catecholamine/GDF15 axis plays a critical role in KC apoptosis, and identify a unique neuro-metabo-immune axis between the gut and liver that elicits hepatoprotection against alcohol-mediated pathogenic challenges.
We identified the predictive factors and prognostic significance of transarterial chemoembolization (TACE) for achieving pathologic complete response (pCR) before curative surgery for hepatocellular ...carcinoma (HCC) in hepatitis B–endemic areas.
Among 753 HCC patients treated with surgery, 124 patients underwent preoperative TACE before liver resection (LR), and 166 before liver transplantation (LT) between 2005 and 2016. Overall survival (OS) and recurrence-free survival (RFS) were analyzed. Pathologic response (PR) was defined as the mean percentage of necrotic area, and pCR was defined as the absence of viable tumor.
A total of 34 (27%) and 38 (23%) patients had pCR before LR and LT, respectively. Alpha-fetoprotein (AFP) < 100 ng/mL and single tumor were significant preoperative predictors of pCR. OS and RFS were significantly improved in patients with pCR or a PR ≥ 90%, but not in patients with PR ≥ 50% after LR and LT. On multivariate analyses, PR ≥ 90% remained an independent predictor of better OS and RFS in LR and LT groups.
Overall, our data clearly demonstrate that pCR predicts favorable prognosis after curative surgery for HCC, and predictors of pCR are AFP <100 ng/mL and single tumor.