MASLD Pushes Liver Disease Beyond the Liver
Metabolic dysfunction-associated steatotic liver disease MASLD is no longer best understood as an isolated hepatic disorder. In this review, the disease is framed as a systemic driver of injury across the heart and kidneys, with metabolic dysfunction-associated steatohepatitis MASH marking a more inflammatory and biologically aggressive state. Hepatic lipid accumulation sits at the center of this process, but the downstream consequences reach far wider than steatosis alone.
Cardiac involvement takes several recognizable forms. Adverse remodeling, diastolic dysfunction, and coronary microvascular dysfunction all emerge from the same metabolic terrain, where excess lipids, chronic inflammation, and vascular stress converge. The liver, in this model, acts less like a passive storage site and more like an endocrine organ broadcasting pathologic signals throughout the circulation.
A single sentence captures the clinical urgency: MASLD is functioning as a whole-body disease.
Lipotoxicity, Inflammation, and the Cardiac Consequences
The cardiac injury pattern described in MASLD is biologically coherent. Systemic lipotoxicity can alter myocardial substrate use, impair relaxation, and strain the myocardium over time. At the same time, inflammation within epicardial adipose tissue may intensify local vascular dysfunction, while a pro-thrombotic milieu adds another layer of ischemic risk. These pathways are not isolated; they reinforce one another, creating a setting in which structural and functional heart disease can evolve quietly.
Coronary microvascular dysfunction deserves particular attention because it can undermine perfusion without the dramatic signature of large-vessel obstruction. In a patient with MASLD, persistent microvascular injury helps explain why symptoms and objective cardiac abnormalities may appear even when conventional coronary evaluation seems less revealing than expected. Diastolic dysfunction fits the same pattern: a stiffening, metabolically stressed ventricle may maintain ejection fraction while losing the ability to fill efficiently.
The review places these abnormalities within a cardio-renal-hepatic axis rather than treating them as coincidental comorbidities. That framing matters because it shifts the target from organ-by-organ reaction to shared upstream biology.
Hepatokines as Signaling Molecules in Organ Cross-Talk
A central theme is altered hepatokine signaling. The liver does not merely reflect metabolic stress; it transmits it. Within that signaling network, brain-derived neurotrophic factor BDNF stands out as a cardioprotective and renoprotective molecule whose downregulation may remove an important brake on injury progression. The loss of that protective signal could leave both the heart and kidneys more vulnerable to the persistent metabolic pressure generated by MASLD.
Nerve growth factor NGF adds complexity rather than simplicity. Its metabolic roles appear dual and context dependent, suggesting that its net effect may vary with disease stage, tissue environment, and inflammatory burden. The same is true for FGF19 and FGF21, which participate in metabolic regulation and appear to influence the trajectory of both cardiac and renal disease. These molecules are not casual biomarkers. They are part of the machinery by which the diseased liver shapes distant organ function.
Profiling these hepatokine signatures could eventually help separate patients with relatively stable steatosis from those moving toward progressive cardiorenal injury. A biomarker strategy built around signaling molecules would be more informative than liver fat alone because it could capture the systemic consequences of metabolic overload rather than just the hepatic depot.
Why the Kidney Deteriorates Alongside the Heart
Chronic kidney disease CKD enters the same pathobiologic frame through overlapping mechanisms. The kidney is exposed to the same inflammatory and lipotoxic environment that affects the heart, and the endocrine signals originating from the diseased liver may amplify that vulnerability. Reduced renoprotective signaling, altered metabolic flux, and chronic vascular stress all help explain why kidney function can deteriorate in parallel with cardiac performance.
This is where the review’s emphasis on cross-talk becomes especially useful. Kidney injury in MASLD is not simply downstream of obesity or diabetes in a generic sense. The hepatic disease itself appears to contribute to renal risk through specific molecular mediators and shared metabolic pathways. In practical terms, that means a patient with MASLD may carry kidney risk that is only partly explained by traditional renal risk factors.
Metabolic Therapies Enter the Cardio-Renal-Hepatic Conversation
Therapeutic interest naturally follows the biology. GLP-1 receptor agonists, SGLT2 inhibitors, and PPAR agonists are described as showing substantial efficacy in improving steatosis, inflammation, and broader metabolic outcomes. Their appeal in MASLD is not limited to liver fat reduction. Each class touches a different part of the systemic network that links hepatocyte stress to cardiac and renal injury.
GLP-1 receptor agonists can improve weight-related and glycemic stress while influencing inflammation and metabolic signaling. SGLT2 inhibitors have a strong clinical reputation in cardiorenal medicine because they affect hemodynamic and metabolic pathways that matter to both organs. PPAR agonists, meanwhile, act on transcriptional programs tied to lipid handling and inflammation, making them attractive candidates for a disease defined by disordered metabolism. In a disorder where liver fat, vascular injury, and renal decline are intertwined, multi-target therapy makes biological sense.
Still, mechanistic plausibility is not the same as proof of organ-specific protection. Improvements in liver inflammation or systemic metabolic status may translate into better cardiovascular and renal outcomes, but the field still needs careful clinical testing to distinguish direct tissue effects from indirect benefits achieved through better overall metabolic control.
Hepatokine Signatures May Define the Next Biomarker Era
The strongest translational opportunity in this review may lie in biomarker development. Specific hepatokine signatures could identify which patients with MASLD are drifting toward accelerated cardiac and renal damage. A signature-based approach would also help determine whether treatment is modifying the disease process itself or simply improving surrogate markers.
That distinction will matter when future trials attempt to connect liver-directed treatment with hard outcomes in the heart and kidneys. Biomarkers that track signaling rather than just anatomy may prove especially valuable in MASH, where inflammatory activity and endocrine disruption are likely to drive faster progression.
A final challenge remains plainly visible: the field must now decide which benefits are real, which are secondary, and which pathways can be targeted directly. The review lays out a persuasive biologic case, but definitive clinical validation is still needed to show whether these therapies protect the heart and kidneys because they repair the underlying cross-talk, or because they improve the metabolic state that feeds it.