The Liver at the Crossroads: Orchestrating Lipoprotein Dynamics and Lipid Homeostasis

The liver plays a central role in numerous physiological processes, with one of its most critical functions being the regulation of lipid homeostasis through both the biogenesis and secretion of very low-density lipoproteins (VLDLs) and fatty acid oxidation. By forming and secreting VLDLs, the liver mitigates the influx of potentially toxic free fatty acids from the bloodstream and repurposes them for energy utilization throughout the body. Fatty acid oxidation is equally essential for maintaining hepatic lipid balance, and its disruption can lead to lipid accumulation and metabolic dysfunction-associated steatotic liver disease (MASLD), previously referred to as non-alcoholic fatty liver disease (NAFLD). Even subtle alterations in these processes can have profound health consequences, contributing to chronic liver diseases and atherosclerosis—the leading cause of cardiovascular morbidity and mortality worldwide. Despite their importance, many aspects of hepatic VLDL formation, secretion, and fatty acid oxidation remain poorly understood. This narrative review highlights the pivotal role of the liver in maintaining lipid balance, summarizes current knowledge on fatty acid uptake and processing, provides an in-depth analysis of VLDL biogenesis and secretion, and underscores the need for continued research in this critical area of human health.