Ketogenesis

Ketogenesis pathway. The three ketone bodies (acetoacetate, acetone, and beta-hydroxy-butyrate) are marked within orange boxes

Ketogenesis is the biochemical process through which organisms produce ketone bodies by breaking down fatty acids and ketogenic amino acids.[1][2] The process supplies energy to certain organs, particularly the brain, heart and skeletal muscle, under specific scenarios including fasting, caloric restriction, sleep,[3] or others. (In rare metabolic diseases, insufficient gluconeogenesis can cause excessive ketogenesis and hypoglycemia, which may lead to the life-threatening condition known as non-diabetic ketoacidosis.)[4]

Ketone bodies are not obligately produced from fatty acids; rather a meaningful amount of them is synthesized only in a situation of carbohydrate and protein insufficiency, where only fatty acids are readily available as fuel for their production.[citation needed]

Recent evidence suggests that glial cells are ketogenic, supplying neurons with locally synthesized ketone bodies to sustain cognitive processes.[5]

  1. ^ Cite error: The named reference Leucine metabolism was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference HMG-CoA was invoked but never defined (see the help page).
  3. ^ Aalling, Nadia Nielsen; Nedergaard, Maiken; DiNuzzo, Mauro (July 16, 2018). "Cerebral Metabolic Changes During Sleep". Current Neurology and Neuroscience Reports. 18 (9): 57. doi:10.1007/s11910-018-0868-9. PMC 6688614. PMID 30014344.
  4. ^ Fukao, Toshiyuki; Mitchell, Grant; Sass, Jörn Oliver; Hori, Tomohiro; Orii, Kenji; Aoyama, Yuka (8 April 2014). "Ketone body metabolism and its defects". Journal of Inherited Metabolic Disease. 37 (4): 541–551. doi:10.1007/s10545-014-9704-9. PMID 24706027. S2CID 21840932.
  5. ^ Silva, Bryon; Mantha, Olivier L.; Schor, Johann; Pascual, Alberto; Plaçais, Pierre-Yves; Pavlowsky, Alice; Preat, Thomas (17 February 2022). "Glia fuel neurons with locally synthesized ketone bodies to sustain memory under starvation". Nature Metabolism. 4 (2): 213–224. doi:10.1038/s42255-022-00528-6. PMC 8885408. PMID 35177854.