Chrono-metabolic regulation of hepatic fibrosis via NR1D1-mediated hepatic stellate cell activation

Abstract

Hepatic fibrosis (HF) is a progressive condition driven by persistent activation of hepatic stellate cells (HSCs), metabolic dysregulation, and inflammatory signaling. Emerging evidence identifies the nuclear receptor NR1D1 as a central node linking circadian rhythms, HIF-1α signaling, and ammonia-mediated HSC activation, providing a mechanistic framework for chrono-metabolic therapeutic strategies. Preclinical studies demonstrate that pharmacological or natural compound-mediated modulation of NR1D1, including Hedyotis diffusa, ferulic acid, and dihydroartemisinin, restores circadian and metabolic homeostasis, attenuates HSC activation, and reduces extracellular matrix deposition. Integrative chrono-informed interventions leveraging NR1D1 offer potential advantages over conventional single-target therapies by synchronizing drug action with endogenous circadian oscillations, optimizing dosing, and enabling multi-pathway modulation. This review highlights the NR1D1-centered chrono-metabolic axis as a promising therapeutic target for HF, emphasizing translational potential and the need for preclinical and early-phase clinical validation.

Key Words: Hepatic fibrosis; NR1D1; Hepatic stellate cells; Circadian rhythm; Chronotherapy; Ammonia metabolism; HIF-1α signaling; Natural compounds

Core Tip: This review summarizes the NR1D1-centered chrono-metabolic regulation of hepatic fibrosis, detailing how circadian rhythms, HIF-1α signaling, and ammonia-mediated hepatic stellate cell activation converge. It emphasizes the therapeutic potential of chrono-informed interventions using pharmacological agents and natural compounds, offering a translational roadmap for more precise and effective antifibrotic strategies.

INTRODUCTION

Hepatic fibrosis (HF) is a dynamic, highly integrated wound-healing response triggered by chronic liver injury. It is characterized by excessive deposition of the extracellular matrix (ECM), disruption of tissue architecture, and progressive evolution toward cirrhosis and hepatocellular carcinoma[1-3]. Globally, liver fibrosis accounts for over one million deaths annually, with major etiologies including chronic viral hepatitis, metabolic dysfunction-associated steatohepatitis/nonalcoholic steatohepatitis (MASH/NASH), and alcohol-related liver disease[4-6]. Despite extensive research, no therapies have yet been approved to directly reverse fibrosis, highlighting a critical unmet clinical need[7-9].

Hepatic stellate cells (HSCs) are central drivers of liver fibrogenesis. In their quiescent state, HSCs primarily store vitamin A-containing lipid droplets. Upon liver injury, they transdifferentiate into activated myofibroblast-like cells, secreting collagen and other ECM proteins that promote fibrosis progression[7,10,11]. HSC activation is orchestrated by multiple factors, including paracrine signals from injured hepatocytes and immune cells, systemic metabolic disturbances, epigenetic modifications, and microenvironmental cues such as oxidative and endoplasmic reticulum stress[12-15]. Hyperammonemia exerts particularly deleterious effects, inducing HSC activation, cytoplasmic vacuolization, endoplasmic reticulum enlargement, and upregulation of pro-fibrotic genes. Pharmacological ammonia-lowering strategies, such as L-ornithine phenylacetate, reduce HSC activation and portal hypertension in preclinical models, emphasizing ammonia metabolism as a potential therapeutic target[12,16]. Beyond HSCs, ammonia also directly induces hepatocyte apoptosis and autophagy via the Bax/Bcl-2 and mTOR/ATG5/LC3BII pathways, creating a pro-fibrotic microenvironment that further exacerbates liver injury[17].

Circadian CLOCK components have emerged as key modulators of HF. Genes including NR1D1, BMAL1, CLOCK, and REV-ERBα regulate HSC activation, cellular metabolism, transforming growth factor-beta (TGF-β) signaling, and inflammatory responses[18-21]. Dysregulation of these CLOCK genes exacerbates fibrosis, whereas pharmacological modulation, such as with melatonin or REV-ERB agonists, attenuates HSC activation and ECM deposition, highlighting the potential of chrono-informed therapeutic strategies[18,21-24]. Recent evidence also suggests bidirectional communication between the liver and central circadian rhythms, whereby liver pathology can disrupt systemic circadian homeostasis, establishing a feedback loop that aggravates disease progression[25].

Non-coding RNAs (ncRNAs), including long ncRNAs and microRNAs, further regulate HSC activation through TGF-β signaling, epigenetic modifications, and competitive endogenous RNA (ceRNA) networks. For instance, MALAT1 and lnc-LFAR1 promote HSC activation via TGF-β signaling, whereas HIF1A-AS1 and lincRNA-p21 inhibit activation through DNA methylation and ceRNA mechanisms[26-28]. Dysregulation of these ncRNAs contributes to both initiation and progression of fibrosis, representing potential molecular targets for therapy.

Complementing these mechanistic insights, natural products and traditional Chinese medicines have shown significant antifibrotic potential. Hedyotis diffusa alleviates CCl4-induced fibrosis by restoring NR1D1 expression, modulating HIF-1α and urea cycle pathways, and regulating gut microbiota-bile acid homeostasis[21,29,30]. Other bioactive compounds, such as ferulic acid, dihydroartemisinin, and eriocitrin, attenuate HSC activation and ECM deposition through TGF-β/Smad signaling, lipophagy regulation, and PPARα-mediated inflammasome modulation[31-35].

Collectively, liver fibrosis arises from a complex interplay among HSC activation, circadian and metabolic dysregulation, inflammatory signaling, and epigenetic control. These interconnections highlight the therapeutic potential of integrated chrono-metabolic interventions and provide a framework for translating mechanistic insights into effective clinical strategies[1,3,22,29,36].

CURRENT ADVANCES

Circadian regulation in HF

Circadian CLOCK machinery plays a critical role in maintaining liver homeostasis and regulating fibrogenesis. HSCs possess functional circadian oscillators, exhibiting rhythmic expression of fibrogenic genes such as NR1D1/Rev-erbα and BMAL1[1,10,18,20,24,37-39]. Disruption of these CLOCK genes enhances HSC activation, ECM deposition, and fibrosis progression[12,40]. Mechanistically, circadian dysregulation affects TGF-β signaling, metabolic pathways, and inflammatory responses in both hepatocytes and HSCs[19,21]. Preclinical studies indicate that restoring circadian function—genetically or pharmacologically (e.g., REV-ERB agonists or melatonin)—suppresses HSC activation and ECM accumulation, highlighting the therapeutic potential of chrono-metabolic regulation. Taken together, these findings suggest that circadian CLOCK components provide temporal control over HSC activation and fibrogenesis, offering a mechanistic foundation for chrono-informed interventions. Table 1 summarizes key circadian regulators and their roles in HSC activation and HF.

Table 1 Key circadian regulators in hepatic stellate cell activation and liver fibrosis.

Circadian gene/regulator	Model/cell type	Intervention/condition	Main findings	Mechanistic insight	Ref.
NR1D1/Rev-erbα	Mouse liver, HSCs	Circadian disruption/CCl4	Dysregulated NR1D1/Rev-erbα; enhanced HSC activation	Loss of NR1D1 promotes TGF-β signaling and ECM deposition	[1,10,20,24]
BMAL1	HSCs, LX2 cells	TGF-β1 induction	Downregulated BMAL1; increased glycolysis and HSC activation	BMAL1 inhibits phenotypic transformation via IDH1/α-KG-mediated glycolysis	[23,38,40]
CLOCK, Per1-3	HSCs	CCl4-induced fibrosis	Reduced CLOCK gene expression	Disruption of CC contributes to HSC proliferation and collagen synthesis	[18,21,37]
REV-ERBα	HSCs, mice	Melatonin/SR9009	Upregulation prevented HSC activation	Modulates circadian clock and PPARα signaling	[18,39]

This table summarizes the primary circadian clock components involved in hepatic stellate cell activation and hepatic fibrosis, including experimental models, interventions, main findings, mechanistic insights, and supporting references. HSC: Hepatic stellate cell; CC: Circadian clock; TGF-β: Transforming growth factor-beta; ECM: Extracellular matrix.

HIF-1α signaling and ammonia-mediated HSC activation

Metabolic stress signals, particularly hyperammonemia, are central drivers of HSC activation. Elevated ammonia promotes HSC proliferation, reactive oxygen species generation, endoplasmic reticulum stress, and upregulation of α-SMA and PDGF-Rβ[12,41]. NR1D1 functions upstream to inhibit HIF-1α signaling, mitigating ammonia-induced HSC activation, stabilizing mitochondrial function, and reducing local inflammatory responses[16,20,29,30,42-44]. This NR1D1–HIF-1α–ammonia axis integrates circadian and metabolic regulation, linking chrono-metabolic dysfunction to fibrogenesis and highlighting ammonia metabolism as a pharmacological target. Pharmacological or genetic restoration of NR1D1 effectively suppresses HSC activation and ameliorates fibrosis progression.

ncRNAs, including MALAT1 and lnc-LFAR1, interact with HIF-1α signaling, modulating ammonia-induced HSC activation through ceRNA networks[26,27]. These examples underscore the multifaceted regulation of HSC activation at both transcriptional and post-transcriptional levels. Taken together, these data support the convergence of circadian modulation and ammonia metabolism in controlling HSC activation, providing a strong rationale for integrated chrono-metabolic interventions. Table 2 presents experimental evidence linking NR1D1 to HIF-1α inhibition and ammonia-mediated HSC activation.

Table 2 Experimental evidence linking NR1D1 to HIF-1α inhibition and ammonia-mediated hepatic stellate cell activation.

Pathway/target	Model/cell type	Intervention	Main findings	Mechanistic insight	Ref.
NR1D1–HIF-1α	LX2, primary HSCs	CCl4-induced fibrosis/NR1D1 overexpression	NR1D1 restoration suppressed HIF-1α, reduced α-SMA and collagen	NR1D1 inhibits HIF-1α signaling, reduces ammonia-mediated HSC activation	[20,29]
Ammonia	LX2, human HSCs	NH4Cl/hyperammonemia	Increased proliferation, ROS, ER stress, α-SMA, PDGF-Rβ	Ammonia promotes HSC activation; toxicity reversed by NR1D1	[12,41]
HIF-1α	HSCs	Hypoxia/metabolic stress	Upregulated fibrogenic genes	HIF-1α drives ammonia-induced fibrogenesis	[19,29]

This table summarizes experimental studies investigating the NR1D1–HIF-1α–ammonia axis, including models, interventions, main findings, mechanistic insights, and supporting references. HSC: Hepatic stellate cell; ROS: Reactive oxygen species; ER: Endoplasmic reticulum; α-SMA: Alpha-smooth muscle actin; PDGF-Rβ: Platelet-derived growth factor receptor beta.

Bioactive compounds and experimental validation

Natural compounds demonstrate potent anti-fibrotic effects by modulating the NR1D1–HIF-1α–ammonia axis. Hedyotis diffusa extracts restore NR1D1 expression, normalize urea cycle function, reduce ammonia accumulation, and attenuate HSC activation in preclinical models[21,22,29]. Other bioactive molecules, including ferulic acid, dihydroartemisinin, and eriocitrin, exert protective effects through TGF-β/Smad signaling, lipophagy regulation, and PPARα-mediated inflammasome modulation[31-33,45-52]. Nanoparticle-based strategies, such as hyaluronic acid–bilirubin conjugates, selectively target activated HSCs and reduce oxidative stress, further mitigating fibrosis[34].

Network pharmacology analyses indicate that these compounds act on multiple nodes within the circadian-metabolic-fibrogenic network, supporting a multi-target, chrono-metabolic intervention approach that may be superior to single-target therapies. Taken together, these findings provide strong experimental validation that chrono-metabolic modulation via natural compounds or pharmacological agents is feasible and effective in preclinical models of HF. Table 3 lists recent preclinical studies of Hedyotis diffusa and other bioactive compounds targeting the NR1D1–HIF-1α–ammonia axis.

Table 3 Recent preclinical studies of Hedyotis diffusa and other bioactive compounds targeting the NR1D1-HIF1-ammonia axis.

Compound/extract	Model	Intervention	Main findings	Mechanistic insight	Ref.
Hedyotis diffusa	CCl4/HF mice, LX2	Hedyotis diffusa extract/injection	Reduced α-SMA, collagen; restored NR1D1	Modulates NR1D1–HIF1–ammonia axis; normalizes urea cycle	[21,29]
Dihydroartemisinin	CCl4 mice, HSCs	Dihydroartemisinin treatment	Restored lipid droplets in HSCs; inhibited activation	NR1D1-mediated Rab7 ubiquitination regulates lipophagy	[32,51,52]
Ferulic acid	LX2 cells, SD rats	TGF-β1/CCl4	Inhibited α-SMA, collagen, p-Smad 2/3	Blocks TGF-β/Smad signaling	[31,47]
Eriocitrin	TAA mice, LX2 cells	Eriocitrin treatment	Reduced inflammasome activation and collagen deposition	PPARα-mediated NLRP1/NLRC4 pathway	[33]
HDW extract	CCl4 mice	HDW treatment	Reduced HSC activation; improved liver function	Modulates gut microbiota, FXR/SHP/CYP7A1 pathway; chrono-metabolic effects	[21]
FA11	CCl4 mice	FA11 treatment	Reduced α-SMA, collagen	Inhibits TGF-β1-induced HSC activation	[46]
Ghrelin	CCl4 mice	Ghrelin treatment	Decreased HSC proliferation, ECM deposition	Modulates HIF-1α and ROS pathways	[45]
Physalin D	HSCs	PD treatment	Reduced HSC activation	Blocks TGF-β/Smad and YAP signaling	[49]

This table summarizes interventions, experimental models, main findings, mechanistic insights, and references for natural and pharmacological compounds affecting the NR1D1–HIF-1α–ammonia pathway. HSC: Hepatic stellate cell; ECM: Extracellular matrix; ROS: Reactive oxygen species; TGF-β: Transforming growth factor-beta.

MAJOR CONTROVERSIES AND UNRESOLVED ISSUES

Despite substantial progress in elucidating the NR1D1–HIF-1α–ammonia axis in HF, several critical controversies and unresolved questions remain, which limit the translational application of chrono-metabolic interventions[1,19]. Here, we highlight three major areas of uncertainty.

Disease-specific applicability of the NR1D1–HIF-1α–ammonia axis

Most mechanistic studies have been conducted in CCl4-induced fibrosis or NASH/MASH models, raising uncertainty regarding the relevance of this axis in other etiologies, including alcoholic liver disease (ALD), drug-induced fibrosis, congenital HF, or nonalcoholic fatty liver disease (NAFLD)-related fibrosis[12,41,53-55]. Differences in liver microenvironment, HSC heterogeneity, and systemic metabolic context may modulate the activity of this pathway and its therapeutic responsiveness. Circadian disruption has been shown to prime HSCs for accelerated activation in NAFLD models, suggesting broader applicability but also mechanistic differences across disease contexts. Expanding experimental validation across multiple fibrosis models is therefore necessary to confirm the generalizability of NR1D1–HIF-1α-ammonia signaling[20,54].

Single-target vs chrono-metabolic integrated interventions

While NR1D1 modulation alone has demonstrated anti-fibrotic efficacy in preclinical models[20,29], HF is a multifactorial disease driven by circadian disruption, metabolic stress, ammonia accumulation, and chronic inflammation[14,30,56]. Bioactive compounds such as dihydroartemisinin and notoginsenoside R1 have been shown to regulate HSC lipophagy via NR1D1-mediated mechanisms and modulate PPAR-γ/TGF-β signaling, respectively, illustrating the potential advantage of multi-target chrono-metabolic strategies over single-node interventions[32,55,56]. It remains unresolved whether targeting a single node is sufficient or if combinatorial strategies—such as NR1D1 activation combined with ammonia-lowering therapy, bile acid modulation, or circadian-aligned pharmacotherapy—are necessary for robust and durable therapeutic outcomes[21,32].

Clinical translation challenges

Implementation of chrono-informed therapies faces practical obstacles. Optimizing dose, timing, and patient stratification is crucial, as individual differences in circadian rhythms, fibrosis stage, and etiology-specific metabolic alterations may profoundly influence treatment efficacy[16,30,57]. Existing preclinical models often fail to fully capture human disease heterogeneity, limiting predictive validity for clinical translation[4,21]. Developing more representative models and incorporating patient-derived systems will be critical to bridge this translational gap and facilitate clinical application.

Taken together, these considerations underscore the need for integrated experimental, preclinical, and clinical strategies to validate the NR1D1–HIF-1α–ammonia axis across diverse fibrosis contexts. Table 4 summarizes key controversies in NR1D1–HIF-1α–ammonia research, detailing issues, supporting evidence, and knowledge gaps.

Table 4 Key controversies in NR1D1–HIF-1α–ammonia axis research.

Controversy	Evidence/context	Knowledge gap	Ref.
Disease-specific applicability	Most mechanistic studies performed in CCl4-induced fibrosis or NASH/MASH models; relevance to ALD, drug-induced fibrosis, congenital fibrosis, or NAFLD unclear	Uncertain if NR1D1–HIF-1α–ammonia axis functions similarly across diverse etiologies; need multi-model validation	[12,41,53-55]
Single-target vs integrated chrono-metabolic therapy	NR1D1 modulation alone shows anti-fibrotic effects; bioactive compounds (e.g., dihydroartemisinin, notoginsenoside R1) regulate multiple HSC pathways including lipophagy, PPAR-γ/TGF-β	Whether single-node targeting is sufficient vs combinatorial strategies integrating NR1D1, ammonia-lowering therapy, bile acid modulation, and circadian-aligned dosing	[20,21,29,32,55,56]
Clinical translation challenges	Variability in circadian rhythms, fibrosis stage, etiology-specific metabolic alterations; existing models often do not reflect human heterogeneity	Optimal dosing schedules, patient stratification, and model selection; incorporation of patient-derived systems for translation	[4,16,21,30,57]

This table summarizes key issues, supporting evidence, and gaps in knowledge for the NR1D1–HIF-1α–ammonia axis, highlighting areas requiring further investigation. HSC: Hepatic stellate cell; NASH: Nonalcoholic steatohepatitis; MASH: Metabolic dysfunction-associated steatohepatitis; ALD: Alcoholic liver disease; NAFLD: Nonalcoholic fatty liver disease.

AUTHOR PERSPECTIVES

NR1D1 has emerged as a pivotal regulatory node in HF, integrating circadian rhythm, HIF-1α signaling, and ammonia metabolism. Experimental evidence demonstrates that NR1D1 activation suppresses HIF-1α–driven transcriptional programs, reduces ammonia accumulation, and limits HSC activation, thereby mitigating fibrogenesis[20-22,29,40]. These multifaceted effects position NR1D1 as a unique chrono-metabolic target, capable of coordinating temporal regulation of both hepatic metabolic and fibrotic pathways.

From a therapeutic perspective, chrono-informed interventions targeting NR1D1 offer distinct advantages. Aligning drug administration with the endogenous circadian oscillation of NR1D1 may optimize efficacy and minimize off-target effects, while simultaneously modulating systemic ammonia levels and HSC activation cycles[18,19,21]. Preclinical studies indicate that natural compounds, such as Hedyotis diffusa extract, ferulic acid, and dihydroartemisinin, can restore NR1D1 expression, normalize downstream HIF-1α and urea cycle pathways, and attenuate HSC activation[21,29,32].

Figure 1 illustrates the proposed mechanistic framework: NR1D1 acts upstream to repress HIF-1α signaling, thereby limiting ammonia-induced HSC activation. Potential pharmacological and botanical intervention points are indicated, including additional modulatory nodes such as bile acid signaling, ncRNAs (e.g., MALAT1 and lnc-LFAR1), and PPARα-mediated inflammasome regulation[26,27,34]. Together, these insights reinforce NR1D1 as a core node for integrated temporal and metabolic control, bridging molecular mechanisms to potential clinical interventions and suggesting that chrono-metabolic strategies may surpass conventional single-target approaches[3,34].

Figure 1 Mechanistic framework of NR1D1-centered chrono-metabolic regulation in hepatic fibrosis. NR1D1 acts as a central circadian-metabolic node, inhibiting HIF-1α signaling and reducing ammonia-induced hepatic stellate cell activation, thereby mitigating fibrogenesis. Pharmacological and natural compounds (e.g., Hedyotis diffusa, ferulic acid, and dihydroartemisinin) restore NR1D1 expression and downstream pathways. Additional modulatory nodes, including bile acid signaling, non-coding RNAs (MALAT1 and lnc-LFAR1), and PPARα-mediated inflammasome regulation, further refine temporal and metabolic control. HSC: Hepatic stellate cell; ECM: Extracellular matrix.

FUTURE DIRECTIONS

Despite substantial progress in elucidating the NR1D1–HIF-1α–ammonia axis, several critical avenues remain for advancing chrono-metabolic interventions toward clinical translation.

Molecular mapping of NR1D1-ligand interactions

Detailed structural characterization, binding kinetics, and ligand specificity studies of NR1D1 are essential to guide rational drug design and the development of potent agonists or modulators[22,32,58]. High-resolution techniques, including X-ray crystallography or cryo-EM, combined with computational docking and molecular dynamics simulations, can identify key residues for selective targeting and optimize ligand efficacy. In parallel, CRISPR/dCas9-based approaches can be employed to modulate NR1D1 expression or activity in HSCs, providing a precise experimental tool for validating structure–function relationships[58].

Transcriptional and epigenetic decoding

Comprehensive profiling of NR1D1-regulated genes in HSCs and hepatocytes using ChIP-seq, RNA-seq, and single-cell transcriptomics will delineate the network of chrono-metabolic control points[20,40,59]. Integration with epigenetic marks, ncRNA regulation (e.g., MALAT1 and lnc-LFAR1), and circadian phase–dependent gene expression can uncover dynamic regulatory circuits governing fibrosis progression, providing mechanistic insight for multi-target interventions. Recent findings demonstrating that the hepatic CLOCK synergizes with HIF-1α to regulate nucleotide availability during liver damage repair further emphasize the importance of deciphering transcriptional networks at high spatiotemporal resolution[60].

Etiological expansion

Current evidence is largely derived from CCl4-induced fibrosis and NASH models. Extending NR1D1-focused studies to MASH, ALD, drug-induced fibrosis, and congenital HF will establish the generalizability of NR1D1–HIF-1α–ammonia targeting strategies[3,5,12]. Comparative analyses across etiologies can identify disease-specific modifiers, refine dosing regimens, and optimize therapeutic interventions. For instance, hypoxiainducible factor2α has been shown to promote fibrosis in NAFLD by enhancing glutamine catabolism and YAP signaling in HSCs, highlighting distinct metabolic cues across disease contexts[61].

Signal translation and microenvironmental crosstalk

Further research is needed to clarify how ammonia and other metabolic cues propagate within the hepatic microenvironment to activate HSCs, including crosstalk with hepatocytes, immune cells, and endothelial components[16,41]. Emerging evidence shows that metabolic regulators such as LOX1 can rewire glutamine–ammonia metabolism to drive liver fibrosis via HSC activation, suggesting additional targetable signaling nodes[62]. Understanding these interactions may reveal additional modulatory nodes for combinatorial chrono-metabolic therapies and allow targeted modulation of systemic and local signals.

Translational validation

Preclinical studies employing chronotherapy designs, coupled with early-phase clinical trials, are critical to establish optimal dosing schedules, therapeutic windows, and patient stratification strategies[30,34]. Incorporating circadian biomarkers, ammonia monitoring, and imaging-based fibrosis assessment can enhance precision interventions, improve reproducibility, and accelerate clinical translation.

Figure 2 presents a translational roadmap integrating molecular mapping, preclinical validation, and clinical application, emphasizing systematic chrono-metabolic interventions from bench to bedside. Collectively, these approaches will enhance mechanistic understanding, refine therapeutic targeting, and accelerate the translation of NR1D1-centered strategies into clinically effective treatments for HF.

Figure 2 Translational roadmap for NR1D1-centered chrono-metabolic interventions in hepatic fibrosis. This framework integrates molecular mapping, transcriptional and epigenetic decoding, multi-etiology validation, signal translation within the hepatic microenvironment, and preclinical and early-phase clinical studies. Each stage represents a step toward translating mechanistic insights into chrono-metabolic therapies, highlighting points for intervention, validation, and optimization from bench to bedside. NASH: Nonalcoholic steatohepatitis; MASH: Metabolic dysfunction-associated steatohepatitis; ALD: Alcoholic liver disease.

CONCLUSION

HF is a progressive stage of chronic liver disease driven by persistent HSC activation, metabolic dysregulation, and inflammatory signaling. NR1D1 emerges as a central regulatory node linking circadian rhythm, HIF-1α signaling, and ammonia-induced HSC activation, providing a mechanistic framework for chrono-metabolic therapeutic strategies. By integrating temporal and metabolic regulation, these approaches enable optimization of dosing, timing, and target specificity, potentially surpassing conventional single-target interventions. Preclinical evidence with Hedyotis diffusa and related compounds supports the feasibility of modulating the NR1D1–HIF-1α–ammonia axis, and translational studies indicate potential for tailored interventions across diverse liver disease etiologies. Future research should refine chrono-metabolic targets, validate disease-specific applicability, and establish optimized chronotherapeutic regimens to improve clinical outcomes.