Search Results (217)

Alcohol-associated hepatitis (AH) is the most severe clinical manifestation of alcohol-associated liver disease. Corticosteroids are the only disease-specific therapy shown to improve short-term survival. Currently, no non-invasive markers are available to predict patient response to corticosteroids or long-term survival in AH. This study investigates whether surface antigens on plasma extracellular vesicles (EVs), key mediators of intercellular communication, can reflect the underlying immune dysregulation in AH and serve as prognostic markers. Patients with AH were prospectively enrolled between 2020 and 2024. Blood samples were collected before corticosteroid initiation during the first 24 h of hospitalization. EVs were characterized using nanoparticle tracking analysis, cryo-electron microscopy, and flow cytometry. Interleukin-6 (IL-6), soluble (s)CD62p, Circulating Vascular Cell Adhesion Molecule-1 (sVCAM), tumor necrosis factor receptor superfamily member 1 (TNRFS1a), and Intercellular Adhesion Molecule 1 (ICAM-1) were quantified by ELISA. Key outcome variables included response to corticosteroids and mortality. A total of 46 patients with AH and 28 healthy donors (HD) were included. EV concentration was significantly higher in AH patients than in HD (9.3 × 10¹¹ [IQR 4–24] versus 2.4 × 10¹¹ [IQR 2–4], p = 0.03). Specific EV antigens were associated with key clinical outcomes: CD20 and CD2 levels differed between patients with or without infections (bacterial, viral, and fungal) developed during hospitalization; CD40 and CD146 were elevated in patients who developed acute kidney injury. EVs enriched in monocyte (CD14) and T-reg (CD25) markers were associated with plasma IL-6 levels, while endothelial markers CD105 and CD146 correlated with sVCAM and sCD62p. EVs enriched in platelet (CD49e) and endothelial (CD31) markers were associated with corticosteroid response, whereas EVs enriched with endothelial (CD105 and CD146) and B lymphocyte (CD19) markers were associated with mortality. Overall, EVs enriched in endothelial and monocyte markers may represent a candidate non-invasive tool for predicting corticosteroid response and mortality in AH, aiding risk stratification and early identification of non-responders for timely transplant evaluation. Full article

Background: Non-alcoholic fatty liver disease (NAFLD) is a prevalent chronic liver disorder associated with impaired lipid metabolism and oxidative stress. As a natural antioxidant and dithiol compound, α-lipoic acid (ALA) may play a beneficial role in modulating hepatic metabolism. This study investigates the potential mechanisms through which ALA may alleviate NAFLD. Methods: To construct an NAFLD model, NCTC 1469 cells were exposed to oleic acid and palmitic acid (OA/PA) and glucose for 24 h. RT-qPCR, Western blotting, and siRNA analyses were used to examine the effects and mechanisms of ALA. In vivo, C57BL/6J mice were fed a high-fat diet for 11 weeks and treated with ALA (200 mg/kg/day, intragastrical) for 4 weeks to evaluate its impact on NAFLD. Results: In NCTC 1469 cells exposed to OA/PA and glucose, ALA markedly reduced lipid accumulation by activating TFEB, which in turn promoted fatty acid β-oxidation and chaperone-mediated autophagy (CMA). Furthermore, ALA activated NRF2-dependent CMA and mitigated oxidative stress. Inhibition of AMPK or silencing of TFEB/NRF2 abolished these effects, indicating the key role of the AMPK–TFEB/NRF2 axis. In HFD-fed mice, ALA alleviated hepatic steatosis, serum lipid abnormalities, and liver injury, consistent with its activation of CMA and β-oxidation and reduction in oxidative stress via this pathway. Conclusions: ALA synchronously activates CMA, β-oxidation, and antioxidant responses via a unified AMPK pathway to reduce lipid accumulation and oxidative stress, providing a mechanistically integrated therapeutic strategy for NAFLD. Full article

Background: Chemokine CCL5 may drive inflammation and vascular risk in advanced liver disease, but its cardiovascular implications are unclear. Secreted by hepatic, endothelial, macrophage, and lymphocytic cells, CCL5 is involved in cytokine regulation. Its serum levels rise in acute liver injury and hepatocellular carcinoma (HCC), but decline with fibrosis progression in end-stage liver disease (ESLD). CCL5 has also been linked to atherosclerosis. This study aimed to evaluate serum CCL5 levels in ESLD patients listed for liver transplantation (LT) and to assess their potential role as markers of cardiovascular (CV) risk and portal hypertension. Methods: We conducted an observational cohort study. Between 2019 and 2022, patients with ESLD evaluated for LT were enrolled. Data on liver pathology, CV risk, and laboratory parameters were collected. Serum CCL5 concentrations were measured using Sigma Aldrich^® CCL5 ELISA kits (MilliporeSigma, St. Louis, MO, USA). The database was analyzed with IBM^® SPSS^® Statistics version 20 (Chicago, IL, USA). Results: Overall, 46 patients were included, 50% with viral hepatitis and 28.3% with alcohol-related liver disease. HCC was present in 37% of cases. The median CV risk scores (CAD_LT = 7, mCAD_LT = 7, CAR_OLT = 18) placed the population at moderate CV risk. Serum CCL5 levels did not vary significantly between viral vs. non-viral cirrhosis (5511.8 vs. 6272.5 pg/mL, p = 0.15) and were not influenced by the presence of HCC (6098.4 vs. 5771.3 pg/mL, p = 0.55). We did not detect a correlation with MELD score (p = 0.21) or CV risk scores (CAD_LT: p = 0.58; mCAD_LT: p = 0.70; CAR_OLT: p = 0.22). Patients with thrombocytopenia (<100,000/µL, 54.3%) or a history of esophageal variceal ligation had lower CCL5 levels (5170.9 vs. 6750.8 pg/mL, p = 0.002 and 4252.0 vs. 6237.5 pg/mL, p = 0.003, respectively). Similarly, patients with a history of previous variceal bleeding and spontaneous bacterial peritonitis (SBP) had lower levels of CCL5 (4373.8 vs. 6119.9 pg/mL, p = 0.02 and 3404.3 vs. 6606.7 pg/mL, p = 0.01, respectively). We found a negative correlation between CCL5 and QTc interval duration (τ = −0.216, p = 0.037), left ventricle size (LV: τ = −0.235, p = 0.027), and pulmonary artery pressure (RV/RA gradient: τ = −0.225, p = 0.03). CCL5 correlated positively with the inflammatory markers C-reactive protein (CRP) (τ = 0.246, p = 0.018) and fibrinogen (r = 0.216, p = 0.04). Conclusions: In liver transplant candidates, serum CCL5 is not associated with cardiovascular risk scores or coronary atherosclerotic burden, but is inversely associated with clinical markers of portal hypertension severity. These findings suggest that CCL5 may serve as a potential non-invasive surrogate marker of portal hypertension rather than a cardiovascular risk biomarker in ESLD. Full article

Liver fibrosis is a common pathological result of chronic hepatic injury caused by various factors, such as viral hepatitis, alcohol-induced liver disease, and metabolic dysfunction-associated steatohepatitis (MASH). It is characterized by an excessive deposition of extracellular matrix, which disrupts the architecture of the liver and can lead to cirrhosis, liver failure, and hepatocellular carcinoma. Globally, nearly 10% of the population has significant fibrosis, with its prevalence increasing with age, obesity, and metabolic syndrome. Despite its significant clinical impact, early detection of liver fibrosis is still limited due to insufficient diagnostic technologies and low public awareness. The increasing burden of MASH emphasizes the urgent need for scalable therapeutic strategies. Currently, liver transplantation is the only definitive treatment, but it is limited by donor shortages and the need for lifelong immunosuppression. However, fibrosis is now recognized as a dynamic and potentially reversible process if the underlying cause is addressed. This shift in understanding has prompted efforts to develop pharmacological agents that target hepatic stellate cell activation, immune system interactions, and metabolic dysfunction. Advances in organoid platforms, multi-omics, and non-invasive diagnostics are accelerating translational research in this area. This review aims to synthesize current knowledge about the molecular drivers of fibrosis, bottlenecks in the current anti-fibrotic drug discovery process, and emerging therapeutic approaches to inform precision medicine strategies and reduce the global burden of chronic liver disease. Full article

Alcoholic liver injury (ALI) is a major global public health issue, with oxidative stress imbalance as its core pathological mechanism. The Kelch-like ECH-associated protein 1–nuclear factor erythroid 2-related factor 2–heme oxygenase-1/glutathione peroxidase 4 signaling pathway (Keap1–Nrf2–HO-1/GPX4) signaling pathway is a key target for regulating hepatic antioxidant defense. This study integrated Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS), Global Natural Products Social Molecular Networking (GNPS) molecular networking, network pharmacology, and animal experiments to systematically explore the hepatoprotective effect and mechanism of Cornus officinalis yeast-fermentation (COF). Component characterization identified 25 bioactive components, including flavonoids, triterpenic acids, and other fermentation-derived metabolites. Network pharmacology identified 441 common targets and 36 core targets of COF and ALI, which were enriched in oxidative stress regulation, inflammatory response, and the Keap1–Nrf2 pathway via Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Molecular docking showed that icariin and other components had stable interactions with Keap1 and Nrf2 (binding energy < −5 kcal/mol). Animal experiments confirmed that COF reduced the liver index of ALI mice, downregulated serum Alanine Aminotransferase (ALT)/Aspartate Aminotransferase (AST) activities, and ameliorated liver pathological damage. Western blot verified that COF inhibited Keap1 expression, promoted Nrf2 nuclear translocation, and upregulated HO-1/GPX4 expression. In conclusion, COF alleviates hepatic oxidative stress by regulating the Keap1–Nrf2–HO-1/GPX4 pathway, providing a scientific basis for its development as a functional food or candidate drug against ALI and a technical paradigm for fermentation-enhanced medicinal plant research. Full article

Background: Cirrhosis represents the final common pathway of chronic liver injury, arising from diverse etiologies such as metabolic, viral, autoimmune, and alcohol-related liver diseases. Despite similar exposures, disease progression varies considerably among individuals, suggesting a genetic contribution to susceptibility and outcome. Objective: This narrative review examines how specific genetic variants influence the risk, progression, and phenotypic expression of cirrhosis. It provides a structured synthesis of established and emerging gene associations, emphasizing their biological mechanisms and potential clinical relevance. Methods: This narrative review synthesizes evidence from all major biomedical and scientific databases, including PubMed, Scopus, Web of Science, and Google Scholar, as well as reference lists of relevant articles, covering literature published between 2005 and 2025 on genetic polymorphisms associated with cirrhosis and its etiological subtypes. Content: Variants are categorized into four mechanistic domains—metabolic regulation, immune modulation, liver enzyme activity, and ancestry-linked expression patterns—representing a novel integrative framework for understanding genetic risk in cirrhosis. Well-characterized variants such as PNPLA3, TM6SF2, HSD17B13, and MBOAT7, along with less commonly studied loci and chromosomal alterations, are discussed in relation to major etiologies, including MASLD/MASH, viral hepatitis, alcohol-related liver disease, and autoimmune conditions. Conclusions: Genetic insights into cirrhosis offer pathways toward early risk stratification and personalized disease management. While polygenic risk scores and multi-omic integration show promise, their clinical translation remains exploratory and requires further validation through large-scale prospective studies. Full article

Alcohol-associated liver disease, particularly severe alcoholic-associated hepatitis (AH), remains a major cause of morbidity and mortality worldwide. Conventional treatments, including corticosteroids, offer limited short-term benefit and are contraindicated in many patients, necessitating exploration of alternative therapies. Fecal microbiota transplant (FMT) has emerged as a novel therapeutic intervention, targeting the gut–liver axis that is disrupted in AH. This review synthesizes the current literature on FMT in the management of alcohol-induced liver injury, examining its pathophysiological basis, clinical efficacy, and implementation challenges. Dysbiosis and increased gut permeability in patients with alcohol use disorder contribute to systemic endotoxemia and hepatic inflammation. FMT aims to restore microbiota diversity and gut barrier integrity, mitigating the progression of liver injury. Some clinical trials have demonstrated encouraging survival benefits and modulation of gut microbiota composition in patients with severe AH. These studies report improved one-year survival rates and reductions in pathogenic bacterial taxa following FMT. However, the field remains nascent, with unresolved questions regarding optimal donor selection, sample preparation, administration routes, and long-term safety. Despite limited large-scale randomized data, FMT shows potential as an adjunct or alternative to existing therapies. Continued research is needed to establish standardized protocols and fully elucidate its role in the treatment algorithm for AH. Given the high mortality associated with untreated severe AH and limitations of current therapies, FMT represents a promising frontier in the management of alcohol-associated liver disease. Full article

Alcoholic liver disease (ALD) is a spectrum of alcohol-induced disorders and represents a major global health challenge. B-cell receptor-associated protein 31 (BAP31) is an endoplasmic reticulum-resident chaperone involved in protein transport, apoptosis, cancer biology, and lipid metabolism. To explore its role in ALD, we used hepatocyte-specific BAP31 knockout mice (BAP31-LKO) and wild-type (WT) littermates exposed to ethanol to assess BAP31′s biochemical and metabolic impact. Following ethanol exposure, BAP31-LKO mice exhibited elevated serum alanine transaminase (23.2%, p < 0.05) and aspartate transaminase (31.4%, p < 0.05) levels compared to WT mice. Increased malondialdehyde (8.5%, p < 0.05) and reduced superoxide dismutase (22.8%, p < 0.05) in BAP31-LKO mice indicate exacerbated liver injury. Furthermore, BAP31 deficiency increased triglyceride (35.7%, p < 0.05) and free fatty acid (16.2%, p < 0.05) accumulation following ethanol treatment, while the expression of fatty acid oxidation-related genes, including Pparα, Cd36, Fatp2, Cpt2, and Acox1, was reduced in BAP31-LKO mice. The mRNA levels of Xbp1, Xbp1s, and Chop, as well as protein levels of p-eIF2α, IRE1α, GRP78, and CHOP, were increased in BAP31-LKO mice compared to WT controls, indicating aggravated ethanol-induced ER stress. Hepatic glycogen content was also reduced in BAP31-LKO mice, along with reduced Ppp1r3c expression, demonstrating impaired glycogen synthesis. Consistently, BAP31 knockdown amplified ethanol-induced lipid accumulation, inflammation, impaired glycogen storage, ER stress, and suppression of Pparα signaling in HepG2 cells. Together, these findings demonstrate that BAP31 deficiency exacerbates ethanol-induced liver steatosis, inflammation, and liver injury by impairing fatty acid oxidation and glycogen synthesis, and by amplifying ER stress responses. Full article

The absence of a unifying pathogenetic mechanism in metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), has significantly hindered therapeutic progress. Appreciation that the delivery of excessive amounts of calories to the liver via the portal circulation might be a key parallel between MASLD and the twin steatotic liver disease, alcohol-related liver disease (ALD), establishes a consolidated framework that could guide rational drug design and precise therapeutic approaches. This review contends that, in both ALD and MASLD, the unique dual blood supply to the liver, from both portal vein and hepatic artery as well as the distinctive blood flow control physiology, prevents hepatic arterial oxygen delivery from adequately compensating for the increased metabolic demands induced by excess caloric intake—alcohol in ALD and food in MASLD—resulting in hepatocellular injury. Over four decades ago, Lautt postulated that this ‘oxygen-nutrient mismatch’ could play a role in ALD. We have extended this paradigm to MASLD, theorizing that analogous mechanisms may be involved in both conditions. Evidence that comorbidities, which are associated with recurrent episodes of hypoxemia, such as obstructive sleep apnea (OSA), exacerbate MASLD progression, supports this. ALD is less strongly linked to metabolic syndrome than MASLD. This may be due to inherent differences in hepatic substrate processing. Carbohydrates, lipids, and proteins undergo diverse and flexible cytosolic metabolic pathways, especially under metabolic stress. In contrast, hepatic ethanol metabolism is predominantly linear and obligately oxidative, providing limited metabolic adaptability. Future perspectives could focus on rectifying the imbalance between hepatic oxygen delivery and nutrient availability. This might be accomplished by attenuating hepatic caloric excess using emerging pharmacotherapies for weight reduction, augmenting hepatic oxygenation through hyperbaric oxygen therapy, or increasing hepatic arterial blood flow with agents such as obeticholic acid. Furthermore, enhancement of hepatic basal metabolic activity with thyroid hormone receptor-β agonists, like resmiritom may confer similar therapeutic effects. Full article

Metabolic dysfunction–associated fatty liver disease (MASLD) is associated with severe forms of liver injury, including fibrosis and cirrhosis. The main risk factors for MASLD—obesity, type 2 diabetes mellitus (T2DM), dyslipidemia, and insulin resistance (IR)—contribute to metabolic disturbances that initiate hepatic steatosis. Metabolic and alcohol-related liver disease (MetALD) describes patients with MASLD who also present alcohol-associated hepatic injury. Chronic oxidative and inflammatory stress promotes the progression of steatosis in both conditions. T2DM and chronic alcohol consumption are independent lifestyle-related risk factors for cirrhosis within the spectrum of metabolic dysfunction–related liver disease (MASLD and MetALD). The coexistence of both conditions may exacerbate hepatic pathological alterations. IR, which is frequently observed in patients with cirrhosis, can lead to the development of a condition known as hepatogenic diabetes (HD). HD is characterized by hyperinsulinemia, IR, and β-cell dysfunction occurring during the onset of cirrhosis and is associated with hepatic inflammation even in the absence of traditional metabolic risk factors such as obesity or a prior history of T2DM. In this context, alcohol intake enhances lipolysis in peripheral tissues, promotes hepatic steatosis, and aggravates metabolic dysfunction, ultimately contributing to excessive mitochondrial production of reactive oxygen species (ROS). Therefore, the present review examines the role of oxidative stress—both alcohol-related and non-alcohol–related—in the pathogenesis of HD, with particular emphasis on ethanol metabolism, oxidative stress, and their interactions in conditions such as T2DM and MetALD. Full article

Alcohol-associated liver disease (ALD) is a leading cause of liver-related morbidity, mortality, and premature death worldwide. Its pathogenesis is complex and incompletely understood, with disrupted methionine metabolism as a key contributor. This pathway converts methionine into S-adenosylmethionine (SAM or SAMe), the principal methyl donor, a precursor of glutathione (GSH), and a critical regulator of hepatocellular function. Alterations in methionine metabolism are primarily driven by downregulation of methionine adenosyltransferase 1A (MAT1A), the liver-specific gene encoding the MATα1 subunit responsible for SAMe biosynthesis. Reduced MAT1A expression and activity lead to hepatic SAMe and GSH deficiency, resulting in global hypomethylation, mitochondrial dysfunction, impaired lipid metabolism, and progressive liver injury, hallmarks of ALD. Recent studies show that MATα1 also localizes to hepatocyte mitochondria, where its selective depletion contributes to mitochondrial dysfunction in ALD. Experimental models demonstrate that SAMe supplementation restores methylation capacity, replenishes GSH, reduces oxidative stress, and improves mitochondrial function and liver histology. Preservation of mitochondrial MATα1 also protects against ALD, underscoring its importance in hepatocellular health. Clinical exploration of SAMe in early-stage ALD suggests potential benefit and motivates continued investigation into treatment strategies that build on and extend beyond supplementation. This review summarizes current knowledge on the role of the MAT1A/SAMe axis in ALD pathophysiology, emphasizing molecular functions and critically evaluating preclinical and clinical evidence for potential therapy. Full article

Chronic binge drinking is common among patients with alcohol-associated steatohepatitis. Therefore, we tested the hypothesis that chronic binge ethanol exposure disrupts mitophagic processing and stimulates release of mitochondrial damage-associated molecular patterns (mtDAMPs), thereby promoting hepatic inflammation and fibrosis after chronic binge ethanol (CBE) exposure in mice using the National Institute of Alcohol Abuse and Alcoholism model. After CBE, hepatic steatosis, liver injury, inflammation, and hepatic stellate cell (HSC) activation occurred. Alda-1, an aldehyde dehydrogenase-2 activator, attenuated these changes. After CBE, mitochondrial depolarization (mtDepo) occurred in ~85% hepatocytes, and mitophagy-associated proteins increased, which Alda-1 blunted. By contrast, transcription factor-EB (master regulator of lysosomal biogenesis) and lysosomal markers decreased, indicating disrupted lysosomal processing. After mitophagy, mitochondrial biogenesis (MB) restores mitochondrial mass and function. After CBE, peroxisome proliferator-activated receptor gamma coactivator-1 alpha (MB regulator), mitochondrial transcription factor-A, oxidative phosphorylation proteins, and fatty acid oxidation all decreased, which Alda-1 largely restored. After CBE, serum mtDAMPs (mitochondrial DNA and cytochrome c) increased 3- to 10-fold. In vitro, mitochondrial DNA stimulated macrophage and HSC activation, which was prevented by toll-like receptor-9 inhibition. In conclusion, CBE increases mtDepo in an acetaldehyde-dependent fashion, leading to mitophagic overburden, disruption of mitochondrial homeostasis, mtDAMP release, and ultimately development of liver inflammation and injury. Full article

Fungal polysaccharides represent a structurally diverse group of bioactive compounds with increasing recognition for their hepatoprotective potential. This review synthesizes current evidence on their roles in the prevention and treatment of liver diseases, including alcohol-related liver disease (ALD), metabolic dysfunction-associated fatty liver disease (MAFLD), or toxin-induced injury. The analyzed studies demonstrate that polysaccharides isolated from species such as Lentinula edodes, Grifola frondosa, Ganoderma lucidum, Coriolus versicolor, and Cordyceps militaris exert beneficial effects by reducing oxidative stress, attenuating inflammation, and improving metabolic homeostasis. Mechanistically, these effects are mediated through the regulation of multiple signaling pathways, including Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB), Nuclear factor erythroid 2–related factor 2 (Nrf2), and NOD-like receptor protein 3 (NLRP3) inflammasome, as well as modulation of gut microbiota. Fungal polysaccharides were also shown to improve hepatic function by lowering serum biomarkers of liver injury and ameliorating histopathological damage. Presented evidence indicates that fungal polysaccharides possess considerable potential as multifunctional hepatoprotective agents, highlighting the need for further mechanistic insight and clinical validation. Full article

Alcoholic liver disease (ALD) caused by excessive alcohol consumption poses a serious threat to human health. Callistephus chinensis (L.) Nees is an herb of the Asteraceae family that has good results in the prevention and treatment of a variety of liver diseases, including multifactorial liver injury, non-alcoholic fatty liver disease/non-alcoholic steatohepatitis, liver fibrosis. Sesquiterpenes are thought to be biologically active components that typically have anti-inflammatory, immunomodulatory, and cardioprotective effects. Callistephus A (CA) is a sesquiterpene compound with a rare 6/7 ring skeleton, which has been isolated only from the Callistephus chinensis Nees. However, the mechanism of action of CA on alcoholic liver disease remains unclear. In this study, alcoholic liver mice were fed with 20 and 40 mg/kg CA, respectively, for 11 days. This study showed that CA improved hepatic steatosis and oxidative stress associated with alcohol consumption. CA alleviated liver inflammation by inhibiting the TLR4/MYD88/NF-κB pathway, ameliorating gut imbalance by restoring the abundance of Akkermansia, and restoring short-chain fatty acids in the gut. Transcriptome analysis revealed that CA primarily affects genes involved in lipid metabolism and inflammation. In vitro, by adding inhibitors of TLR4 (TAK-242) and AMPK (Dorsomorphin), it was confirmed that CA alleviates ALD by inhibiting TLR4 and activating AMPK. This study is the first to demonstrate that CA protects against alcoholic liver disease through the regulation of the gut flora and modulation of the AMPK/NF-κB pathway. In conclusion, CA can effectively improve alcoholic liver disease and can be used as an effective candidate drug with liver-protective effects. Full article

Background: Periodontal dysbiosis contributes to liver injury through systemic inflammation, oral–gut microbial translocation, and endotoxemia. Lipopolysaccharides (LPSs) and virulence factors derived from periodontal pathogens, particularly Porphyromonas gingivalis (P. gingivalis) activate Toll-like receptor (TLR) signaling, trigger NF-κB-mediated cytokine release (e.g., TNF-α, IL-1β, IL-6), and promote oxidative stress and Kupffer cell activation within the liver. The present systematic review summarized clinical evidence supporting these mechanistic links between periodontal pathogens and hepatic outcomes, highlighting the role of microbial crosstalk in liver pathophysiology. Methods: A PRISMA-compliant systematic review was conducted by searching PubMed, Scopus, and the Cochrane library, as well as gray literature. Eligible study designs were observational studies and trials evaluating P. gingivalis and other periodontal pathogens (Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Tannerella forsythia) for liver phenotypes (Non-Alcoholic Fatty Liver Disease [NAFLD]/Metabolic Dysfunction-Associated Steatotic Liver Disease [MASLD], fibrosis/cirrhosis, acute alcoholic hepatitis [AAH], and Hepatocellular carcinoma [HCC]). Risk of bias was assessed using the Newcastle–Ottawa Scale adapted for cross-sectional studies (NOS-CS) for observational designs and the RoB 2 scale for single randomized controlled trials (RCTs). Due to the heterogeneity of exposures/outcomes, results were summarized narratively. Results: In total, twenty studies (2012–2025; ~34,000 participants) met the inclusion criteria. Population-level evidence was conflicting (no clear association between anti-P. gingivalis serology and NAFLD), while clinical cohorts more frequently linked periodontal exposure, particularly to P. gingivalis, to more advanced liver phenotypes, including fibrosis. Microbiome studies suggested stage-related changes in oral communities rather than the effect of a single pathogen, and direct translocation into ascitic fluid was not observed in decompensated cirrhosis. Signals from interventional and behavioral research (periodontal therapy; toothbrushing frequency) indicate a potential modifiability of liver indices. The overall methodological quality was moderate with substantial heterogeneity, precluding meta-analysis. Conclusions: Current evidence supports a biologically plausible oral–liver axis in which periodontal inflammation, often involving P. gingivalis, is associated with liver damage. Causality has not yet been proven; however, periodontal evaluation and treatment may represent a low-risk option in periodontitis-associated NAFLD. Well-designed, multicenter prospective studies and randomized trials with standardized periodontal and liver measurements are needed. Full article