Effect of an Enteral Diet Containing Medium-Chain Triglyceride on Protein Metabolism in Septic Rats.

Abstract

SummaryWe studied the effects of an enterally administered diet containing medium-chain triglycerides (MCT) on protein metabolism in septic Wistar rats and compared them with those of a long-chain triglycerides (LCT). The sepsis was induced by cecal ligation and puncture. The rats were divided into two groups. One group was fed a diet containing a MCT and LCT mixture (MCT/LCT), and the other was fed one containing LCT, as 10% of total energy. The diets also contained protein, dextrin, vitamins, and electrolytes. The experimental diets were via an intraduodenal catheter for 6 days. The MCT/LCT group showed a higher nitrogen balance after 3 days of the feeding and a higher liver protein content compared with the LCT group on the last day. Furthermore, the concentrations of serum total protein and albumin in the MCT/LCT group were higher than those in the LCT group. These results indicate that the enteral diet containing MCT combined with LCT may be advantageous to protein metabolism in septic rats over the diet with LCT alone. require a supplement of energy sufficient to compensate for the deficit. Generally fats are a more effective energy source than carbohydrates or proteins because of their high caloric value. However the utilization of fats, in particular long-chain triglycerides (LCT), might be impaired in sepsis [4,5], because the level of carnitine, which is essential for oxidation of LCT, is decreased in blood [6] and tissues [7] in the septic state.On the other hand, medium-chain triglycerides (MCT) are different from LCT in their metabolism, for MCT can be used as an energy source without carnitine in the liver and other organs [8] . Therefore, MCT may be preferred for septic patients over LCT as the energy source [9,10] . However, as MCT are exclusively saturated fatty acids, an essential unsaturated fatty acid such as linoleic acid must be supplemented by blending with LCT for the nutritional requirement of the patients. Several investigators reported that a mixture of intravenously injected MCT/LCT was more advantageous as an energy source under seriously stressful conditions than LCT or glucose [11][12][13]. However, effects of enteral administration of MCT/LCT in sepsis have rarely been reported.Recently, enteral nutrition was reported to be advantageous for patients with intestine dysfunction and immuno suppression [14][15][16]. We also reported beneficial effects of enteral diet containing fat as about 10% of total calories on septic rats [17]. In the present study, we investigated the efficacy of the enteral liquid diet containing 10% MCT/LCT compared with one having LCT as fat on protein metabolism in septic rats, because the accelerated breakdown of body protein in sepsis can cause serious clinical problems [18].

Medium-chain triglyceride-rich enteral nutrition is more effective than low-fat enteral nutrition in rat colitis, but is equal in enteritis

“…MCTs have also been reported to be effective in a septic rat model, in which they improved the nitrogen balance (because they are rapidly metabolized and produce nonesterified fatty acids and ketones as energy sources). 15 ED contains crystalline amino acids, while, on the other hand, TL contains oligopeptides as a nitrogen source. Therefore, it may be an over-simplification to attribute the effects of these agents to the fat component only.…”