Hepatic Zonation Disturbances in Chronic Liver Disease: Mechanisms, Clinical Implications, and Therapeutic Perspectives

Abstract

Hepatic zonation, the spatial division of metabolic functions along the porto-central axis of the liver lobule, is critical for homeostasis. Disturbance of this finely regulated zonation is increasingly recognized as a central feature of chronic liver disease (CLD), influencing disease progression, clinical manifestations, and therapeutic response. This review synthesizes recent scientific advances in the understanding of zonation disturbances in CLD, highlights clinical and diagnostic implications, and discusses emerging therapies targeting the restoration of zonal architecture and function.

Introduction

Chronic liver disease encompasses a spectrum of disorders marked by persistent hepatocellular injury, inflammation, and fibrosis, ultimately leading to cirrhosis and liver failure. The liver's unique microarchitecture, defined by hepatic zonation, orchestrates key metabolic, detoxification, and synthetic processes. Disruption of zonation during CLD alters these functions, contributing to diverse pathophysiological and clinical outcomes. Understanding the mechanisms and consequences of zonation disturbances is crucial for accurate diagnosis, prognostication, and targeted management of CLD.

Epidemiology / Disease Burden

Globally, CLD affects over 1.5 billion individuals, with non-alcoholic fatty liver disease (NAFLD), alcoholic liver disease (ALD), and viral hepatitis representing the most prevalent etiologies. Zonation disturbances underpin the progression of these conditions, yet their epidemiological quantification remains challenging due to limited histological and imaging markers. Recent population-based studies utilizing spatial transcriptomics and advanced imaging have revealed that zonation perturbations are detectable even at early disease stages, underscoring their widespread relevance across diverse CLD populations.

Pathophysiology

Hepatic lobules are organized into zones (periportal, midzonal, and pericentral) defined by gradients of oxygen, nutrients, hormones, and signaling molecules. Each zone specializes in distinct metabolic pathways, such as gluconeogenesis (periportal) and xenobiotic metabolism (pericentral). In CLD, chronic injury disrupts these gradients, leading to loss of metabolic compartmentalization. Key mechanisms include sinusoidal capillarization, altered Wnt/β-catenin and hypoxia-inducible factor (HIF) signaling, and aberrant extracellular matrix deposition. Hepatocyte plasticity is impaired, while Kupffer cell and stellate cell activation propagate a vicious cycle of inflammation and fibrosis, further distorting zonal identity and function.

Risk Factors

Risk factors for hepatic zonation disturbances mirror those for CLD, including metabolic syndrome, obesity, diabetes, chronic alcohol use, viral hepatitis, and genetic predispositions. Environmental toxins and certain medications exacerbate zonal vulnerability, particularly in pericentral hepatocytes, which are rich in cytochrome P450 enzymes. Emerging evidence suggests that gut microbiota dysbiosis and altered bile acid signaling may further modulate zonation integrity in susceptible individuals.

Clinical Features

Disturbances in hepatic zonation manifest variably, depending on the predominant zone affected and the underlying etiology. Loss of pericentral function impairs ammonia detoxification and drug metabolism, predisposing to hepatic encephalopathy and drug toxicity. Periportal disruption affects glucose and lipid homeostasis, exacerbating metabolic dysregulation. Clinically, zonation disturbances contribute to the heterogeneity of laboratory abnormalities and may underlie atypical presentations or rapid disease progression in certain patients. Advanced non-invasive imaging (e.g., MRI-based elastography, contrast-enhanced ultrasound) and spatial transcriptomics are improving recognition of these phenotypes.

Diagnosis

Accurate diagnosis of zonation disturbances currently relies on histopathological examination, with immunohistochemical and molecular markers delineating zone-specific alterations. Advances in spatial transcriptomics and single-cell RNA sequencing now enable high-resolution mapping of zonal gene expression, enhancing diagnostic precision. Non-invasive imaging modalities are under investigation for their potential to detect zonal fibrosis and vascular changes. Integration of spatial omics with traditional biomarkers promises improved staging and prognostication in CLD.

Treatment & Management

Current management of CLD is etiology-driven, focusing on removing insults (e.g., antiviral therapy, alcohol cessation, metabolic control) and mitigating complications. Although direct restoration of zonal architecture is not yet clinically available, interventions targeting upstream drivers (e.g., Wnt pathway modulators, antioxidants) may indirectly preserve zonation. Supportive therapies addressing metabolic, detoxification, and synthetic deficits are tailored to individual zonal dysfunction. Liver transplantation remains the definitive therapy for end-stage zonation loss with liver failure.

Recent Advances / Emerging Therapies

Recent therapeutic innovations aim to restore or mimic zonal function. Small molecule modulators of Wnt/β-catenin and HIF signaling are in preclinical and early clinical development, showing promise in re-establishing metabolic compartmentalization. Organoid and bioengineered liver models now enable high-throughput screening of zonation-restorative compounds. Gene editing and cell-based therapies targeting specific zones are under investigation, with initial data suggesting potential to reverse established zonal disturbances and ameliorate disease progression.

Guideline Recommendations

While major hepatology guidelines do not yet recommend routine assessment of zonation disturbances, expert consensus emphasizes the importance of recognizing their clinical impact, particularly in atypical presentations or rapid progression of CLD. Multidisciplinary management incorporating histopathological, molecular, and imaging data is advocated for complex cases. Ongoing guideline updates are expected to address evolving diagnostic and therapeutic modalities targeting zonation integrity.

Conclusion

Hepatic zonation disturbances represent a fundamental and clinically significant aspect of chronic liver disease pathogenesis and progression. Advances in molecular and imaging technologies are enhancing recognition of zonal dysfunction, with emerging therapies poised to target underlying mechanisms. Greater understanding of zonation biology will refine risk stratification, enable personalized interventions, and ultimately improve outcomes for patients with CLD. Continued integration of zonation insights into clinical practice is essential for the next era of hepatology.