Octanoate

Management of acute MCADD includes rapid correction of hypoglycemia, rehydration and treatment of the underlying infection or other stress factor. Current long-term therapy includes avoidance of fasting and a high carbohydrate low-fat diet, but it does not fully prevent the crises and the neurological alterations. (A15457)

Octanoic (OA) and decanoic (DA) acids are the predominant metabolites accumulating in medium-chain acyl-CoA dehydrogenase (MCAD; E.C. 1.3.99.3) deficiency (MCADD), the most common inherited defect of fatty acid oxidation. Glycine and l-carnitine bind to these fatty acids giving rise to derivatives that also accumulate in this disorder. The clinical presentation typically occurs in early childhood but can occasionally be delayed until adulthood. The major features of the disease include hypoglycemia, vomiting, lethargy and encephalopathy after fasting, infection or other metabolic stressors. (A15457)

It has been demonstrated that octanoic (OA) and decanoic (DA) acids compromise the glycolytic pathway and citric acid cycle functioning, increase oxygen consumption in the liver and inhibit some activities of the respiratory chain complexes and creatine kinase in rat brain (A15454, A15455). These fatty acids were also shown to induce oxidative stress in the brain (A15456). Experiments suggest that OA and DA impair brain mitochondrial energy homeostasis that could underlie at least in part the neuropathology of MCADD. (A15457)

MCADD presents in early childhood with hypoketotic hypoglycemia and liver dysfunction, often preceded by extended periods of fasting or an infection with vomiting. Infants who are exclusively breast-fed may present in this manner shortly after birth, due to poor feeding. In some individuals the first manifestation of MCADD may be sudden death following a minor illness. A number of individuals with MCADD may remain completely asymptomatic, provided they never encounter a situation that sufficiently stresses their metabolism. (Wikipedia)

The enzyme MCAD (medium-chain acyl-CoA dehydrogenase) is responsible for the dehydrogenation step of fatty acids with chain lengths between 6 and 12 carbons as they undergo beta-oxidation in the mitochondria. Fatty acid beta-oxidation provides energy after the body has used up its stores of glucose and glycogen. This typically occurs during periods of extended fasting or illness when caloric intake is reduced, and energy needs are increased. Beta-oxidation of long chain fatty acids produces two carbon units, acetyl-CoA and the reducing equivalents NADH and FADH2. NADH and FADH2 enter the electron transport chain and are used to make ATP. Acetyl-CoA enters the Krebs Cycle and is also used to make ATP via the electron transport chain and substrate level phosphorylation. When the supply of acetyl-CoA (coming from the beta-oxidation of fatty acids) exceeds the capacity of the Krebs Cycle to metabolize acetyl-CoA, the excess acetyl-CoA molecules are converted to ketone bodies (acetoacetate and beta-hydroxybutyrate) by HMG-CoA synthase in the liver. Ketone bodies can also be used for energy especially by the brain and heart; in fact they become the main sources of energy for those two organs after day three of starvation. (Wikipedia)

Caprylic acid is found naturally in the milk of various mammals, and as a minor constituent of coconut oil and palm kernel oil. It is also an endogenously produced metabolite found in the human body. Caprylic acid is used commercially in the production of esters used in perfumery and also in the manufacture of dyes. Caprylic acid is an antimicrobial pesticide used as a food contact surface sanitizer in commercial food handling establishments on dairy equipment, food processing equipment, breweries, wineries, and beverage processing plants. It is also used as disinfectant in health care facilities, schools/colleges, animal care/veterinary facilities, industrial facilities, office buildings, recreational facilities, retail and wholesale establishments, livestock premises, restaurants, and hotels/motels. In addition, caprylic acid is used as an algaecide, bactericide, and fungicide in nurseries, greenhouses, garden centers, and interiorscapes on ornamentals. Products containing caprylic acid are formulated as soluble concentrate/liquids and ready-to-use liquids. The acid chloride of caprylic acid is used in the synthesis of perfluorooctanoic acid. Caprylic acid has medical uses as a medium-chain triglyceride. Caprylic acid is also used in the treatment of some bacterial infections. Due to its relatively short chain length it has no difficulty in penetrating fatty cell wall membranes, hence its effectiveness in combating certain lipid-coated bacteria, such as Staphylococcus aureus and various species of Streptococcus. The octanoic acid breath test is used to measure gastric emptying. Some potential benefit is possible from administration of octanoic acid for patients with Essential tremor. Caprylic acid is taken as a dietary supplement. It is believed to suppress fungal infections within the gut, notably candida albicans infection. (Wikipedia)