Disease relevance of octanoic acid

• The finding of almost threefold more decanoic acid (C10:0) than octanoic acid (C8:0), despite the presence of considerably more octanoic acid in the original diet, suggests that trioctanoin may be a preferable medium-chain triglyceride substrate for the nonsurgical treatment of chylothorax [1].
• Growth of Mycobacterium tuberculosis relies on a pathway in which the lipoate attachment group is synthesized from an endogenously produced octanoic acid moiety [2].
• Monitoring enzyme replacement treatment in exocrine pancreatic insufficiency using the cholesteryl octanoate breath test [3].
• Several short chain fatty acids, including octanoate, are increased in the plasma of patients with hepatic encephalopathies and Reye syndrome [4].
• This pathway was tested by labeling a PDH domain with deuterated octanoate in an E. coli strain devoid of LipA activity [5].

Psychiatry related information on octanoic acid

• Our recent research has indicated that intracerebroventricular (i.c.v.) and intraperitoneal (i.p.) administration of n-octanoic acid-modified ghrelin (acyl ghrelin) stimulates food intake and locomotor activity in the goldfish [6].
• Such incorporation could be obtained under reaction temperature, 45 degrees C; substrate ratio, 9mol/mol caprylic acid/PC; water addition of 2%; 30wt.% immobilized enzyme; and reaction time, 48h [7].
• Infusion of octanoate, which has been reported to be ineffective in reducing eating behavior, did not increase intestinal LDH activity relative to saline infusion [8].
• Lactation or food deprivation did not alter rates of hepatic peroxisomal beta-oxidation of palmitate or octanoate in cows [9].

High impact information on octanoic acid

• Oleate, but not octanoate, requires carnitine binding to gain access to the mitochondrial matrix; hence, if glucose and/or insulin limit long-chain fatty acid entrance into the mitochondria, then, during the clamp, long-chain acylcarnitine formation should be decreased, causing a decrease in oleate, but not octanoate, oxidation [10].
• Octanoic acid stimulated lymphocyte rolling but did not affect lymphocyte adherence [11].
• Olive oil or octanoic acid was placed into the duodenum, and Peyer's patch microcirculation was observed by intravital fluorescence microscopy [11].
• Olive oil enhanced the expression of both alpha4-integrin and L-selectin on lymphocytes, whereas octanoic acid only increased the expression of L-selectin [11].
• Measurement of gastric emptying rate of solids by means of a carbon-labeled octanoic acid breath test [12].

Chemical compound and disease context of octanoic acid

• To investigate the role of hyperglycemia for octanoate-induced secretion, nondiabetic rats were made hyperglycemic by 48-h glucose infusions [13].
• Two postmortem plasma samples from victims of infant sudden-death syndrome had detectable octanoate and decanoate, but cis-4-decenoate could not be detected [14].
• The respiratory rate of intact cells was significantly decreased by sepsis, with glycerol or octanoate as exogenous substrates, whereas oxidative phosphorylation (ATP-to-O ratio or respirations in state 4, state 3 and the oligomycin-insensitive state as well as the uncoupled state) was unchanged in permeabilized hepatocytes [15].
• The abilities of the Escherichia coli lipoic acid auxotrophs W1485-lip2 and JRG33-lip9 to grow on succinate medium in the presence of octanoate, 8-mercaptooctanoate, or 6-mercaptooctanoate have been determined [16].
• The compound was administered as an emulsion of cholesteryl octanoate, triglyceride, and lecithin to rats with mild pancreatic insufficiency induced by injecting the pancreatic duct with zein [17].

Biological context of octanoic acid

• The test is based on the hydrolysis of cholesteryl-[1-14C]octanoate by pancreatic carboxyl ester lipase (cholesterol esterase) with subsequent absorption and hepatic metabolism of the liberated octanoate to 14CO2 [18].
• Structural comparison of LipB with lipoate protein ligase A indicates that, despite conserved structural and sequence active-site features in the two enzymes, 4'-phosphopantetheine-bound octanoic acid recognition is a specific property of LipB [2].
• In the presence of octanoate, (i) the rate of the citric acid cycle decreases from 0.25 to 0.13 mumol/min x g wet weight which are one-third and one-sixth of the rate of pyruvate carboxylation, and (ii) the rate of gluconeogenesis increases from 0.65 to 0.83 mumol/min x g wet weight [19].
• Competitive binding of long-chain free fatty acids, octanoate, and chlorophenoxyisobutyrate to albumin [20].
• Indeed, preparations of highly purified mitochondria from glucose-starved root tips were able to oxidize octanoate and palmitate to give organic acids of the tricarboxylic acid cycle [21].

Anatomical context of octanoic acid

• The influence of mixtures of taurocholate (TC), oleic acid (OA), caprylic acid (CA), and monolein (MO) on the toxic effects of deoxycholate (DC) in rat jejunum have been investigated using both a closed loop and perfusion technique [22].
• The results predict that the relative affinity of octanoic acid for albumin and membranes will be similar to that of long-chain fatty acids (e.g., oleic acid), but the rate of equilibration will be approximately 10(4) faster for octanoic acid [23].
• DL-1,2-Dioctanoylglycerol (1,2-DiC8) added to human peripheral resting T lymphocytes was rapidly metabolized to produce octanoic acid and further to small molecules, probably by the action of diacylglycerol lipase and/or nonspecific esterase [24].
• Acetate, octanoate, and palmitate inhibited the glucose-induced activation of l-PK transcription in ChREBP-overexpressed hepatocytes [25].
• Exogenous free fatty acids such as octanoate and palmitate (classical stimulators of respiration in brown adipocytes) were also able to dramatically inhibit Ca2+ uptake by the cells [26].

Associations of octanoic acid with other chemical compounds

• Ammonia, octanoate and a mercaptan depress regeneration of normal rat liver after partial hepatectomy [27].
• In the isolated perfused liver metabolizing lactate, the inhibitory effect of octanoate on gluconeogenesis was partially relieved by the addition of 1 mM NH4Cl, but remained unchanged in the presence of 2 mM NH4Cl, despite a highly oxidized NAD+/NADH ratio in the mitochondria [28].
• The levels of acetyl-CoA in heart and liver mitochondria oxidizing octanoate during state 3 respiration were lower than those obtained with pyruvate [29].
• Hexanoate and octanoate inhibit transcription of the malic enzyme and fatty acid synthase genes in chick embryo hepatocytes in culture [30].
• We conclude that octanoate increases the oxidation of leucine in skeletal muscle by increasing the activation of BCKA dehydrogenase [31].

Gene context of octanoic acid

• It is concluded that octanoic acid stimulates de PMA1 ATPase activity by posttranslational mechanisms [32].
• Ghrelin has a unique post-translational modification: the hydroxyl group of the third amino acid, usually a serine but in some species a threonine, is esterified by octanoic acid and is essential for ghrelin's biological activities [33].
• Octanoate reduces very low-density lipoprotein secretion by decreasing the synthesis of apolipoprotein B in primary cultures of chicken hepatocytes [34].
• Regulation of the expression of the H(+)-ATPase genes PMA1 and PMA2 during growth and effects of octanoic acid in Saccharomyces cerevisiae [32].
• Addition to the perfusate of a medium-chain fatty acid (caprylic acid) that does not require CD36 for uptake alleviated poor ischemic tolerance of CD36-null hearts [35].

Analytical, diagnostic and therapeutic context of octanoic acid

• 14C can be replaced by 13C for labeling the octanoic acid used in the breath test [12].
• Biological assays revealed that retention of activity was inversely dependent both on the number of chains introduced and on their length; activity was most conserved (greater than 50%) in a TNF preparation modified with only approximately 1-2.5 caprylic acid (C8) residues/trimer [36].
• For octanoic acid bound to BSA (6:1, mol/mol), the chemical shift of the only FA carboxyl resonance (designated as peak c), plotted as a function of pH, exhibited a complete sigmoidal titration curve that deviated in shape from a corresponding theoretical Henderson-Hasselbach curve [37].
• Intrahepatic implants of M114 carcinoma in B6D2F1/J mice were treated by intraperitoneal injection of 30 mg sodium caprylate (octanoate), and implants of Nb2 lymphoma in Nb rats were treated with 300 mg tricaprylin orally [38].
• Effects of octanoic acid on monoamines and their acidic metabolites in the rat brain were analyzed by HPLC [39].

References