Mitochondrial and peroxisomal beta-oxidation

Beta-oxidation refers to the catabolic process in which **fatty acids** are broken down into acetyl-CoA units, producing NADH and FADH₂, which subsequently fuel ATP synthesis. **Mitochondrial beta-oxidation** is the primary pathway for the energy-yielding oxidation of short-, medium-, and long-chain fatty acids, vital for tissues with a high energy demand such as the heart and liver. **Peroxisomal beta-oxidation**, in contrast, specializes in shortening very long chain fatty acids (VLCFAs), branched-chain fatty acids, and certain prostaglandins, producing H₂O₂ as a byproduct. The peroxisomal process is not directly linked to ATP generation; instead, its products are transferred to the mitochondria for further oxidation[1][4][7]. Both mitochondrial and peroxisomal beta-oxidation consist of enzyme complexes or multifunctional proteins that mediate consecutive steps, including oxidation, hydration, dehydrogenation, and thiolysis. Many of the genes controlling these enzymes are regulated by the nuclear receptor **peroxisome proliferator-activated receptor alpha (PPAR alpha)**, which is the canonical therapeutic target in the context of fatty acid oxidation modulation (e.g., by fibrates)[7]. Disorders of either pathway can result in **fatty acid oxidation disorders**, hepatic steatosis, or metabolic syndromes[4][7]. Beta-oxidation is a crucial part of systemic energy metabolism and is also involved in modulating immune cell function and systemic lipid homeostasis[3][6].

Other names

beta-oxidation of fatty acidsfatty acid beta-oxidationmitochondrial beta-oxidationperoxisomal beta-oxidation

Activation of peroxisome proliferator-activated receptor alpha (PPAR alpha) to upregulate expression of pathway enzymes; Modulation of fatty acid metabolism to lower triglyceride levels