Hepatic fatty acid oxidation

**Hepatic fatty acid oxidation** refers to the metabolic process by which the liver breaks down fatty acids primarily through mitochondrial and peroxisomal β‑oxidation pathways. This process is essential for energy production, especially during fasting or periods of increased energy demand. In mitochondria, long-chain fatty acids undergo sequential removal of two-carbon units as acetyl-CoA via a four-step cycle involving dehydrogenation, hydration, another dehydrogenation, and thiolysis; this acetyl-CoA then enters the tricarboxylic acid cycle for further ATP generation[1]. Peroxisomes are responsible for oxidizing very-long-chain fatty acids that cannot be processed by mitochondria until they are shortened sufficiently[6]. The regulation of hepatic fatty acid oxidation involves several nuclear receptors and signaling pathways. The most prominent is **peroxisome proliferator–activated receptor alpha** (**PPARα**), which upregulates genes encoding enzymes required for both mitochondrial and peroxisomal β‑oxidation in response to fasting or pharmacologic activation by fibrates[3][6]. The **liver X receptor alpha** (**LXRα**) also regulates the expression of key enzymes in peroxisomal β‑oxidation independently from PPARα[6]. Glucagon stimulates hepatic fat oxidation via PPARα-dependent mechanisms involving AMP‑activated protein kinase signaling during fasting states[3]. Impairments in hepatic fat oxidation contribute significantly to metabolic diseases such as nonalcoholic fatty liver disease (NAFLD), obesity-related insulin resistance, and other components of metabolic syndrome. While not a single molecular target but rather a pathway comprising multiple enzymes and regulatory proteins—including acyl-CoA dehydrogenases, enoyl-CoA hydratase, hydroxyacyl-CoA dehydrogenase, thiolase—therapeutic strategies often focus on modulating these regulators or their upstream effectors. Because "hepatic fatty acid oxidation" describes a complex pathway rather than an individual molecule or canonical drug target such as an enzyme or receptor subunit—and encompasses multiple molecular entities—it should not be considered a single therapeutic target according to standard nomenclature conventions. Therefore: > There is something incorrect with this entry as it does not refer to one specific molecule/receptor but rather an entire metabolic process/pathway. References supporting statements above include [1], [3], [5], [6].

Other names

Liver fatty acid oxidationhepatic β-oxidationliver lipid oxidation

Activation of peroxisome proliferator–activated receptor alpha (PPARα) to increase expression of genes involved in mitochondrial and peroxisomal β‑oxidation[3][6] Activation of liver X receptor alpha (LXRα) to induce peroxisomal β‑oxidation[6]