Medium-chain triglycerides enhance secretory IgA expression in rat intestine after administration of endotoxin

Abstract

The purpose of this study was to determine whether medium-chain triglycerides (MCTs) modulate the inflammatory immune response to LPS and enhance the expression of secretory IgA in the rat intestine. Rats were given either corn oil or MCTs by gavage daily for 1 wk, and LPS or saline vehicle was administered via the tail vein. They were then killed, and serum and sections from the gut were collected for further analysis. Western blot analysis for secretory IgA revealed that MCTs significantly enhanced its expression in the ileum compared with corn oil in rats administered saline. After LPS challenge, expression of secretory IgA was decreased in the corn oil group but not in the MCTs group. The mRNA expression of IL-6 was assessed by real-time RT-PCR, because IL-6 regulates secretory IgA in the intestine. The expression was significantly greater in the MCTs group than in the corn oil group after LPS injection. Increases in expression of proinflammatory cytokines or chemokines such as TNF-alpha, IL-18, macrophage inflammatory protein-2, and monocyte chemoattractant protein-1 in the ileum were significantly blunted by MCTs. In addition, the mRNA expression of the Th2 IgA-stimulating cytokine IL-10 in the ileum and Peyer's patches was significantly greater in the MCTs than the corn oil group. In contrast, the mRNA expression of the Th1 IgA-inhibiting cytokine interferon-gamma was blunted by MCTs. As a result, intestinal injury was significantly reduced. Therefore, MCTs protect the gut by modulating the immune response to LPS and enhancing secretory IgA expression.

Medium-chain triglycerides enhance mucous secretion and cell proliferation in the rat

“…The calorie intake from the daily fat supplement was 45 Kcal/kg per day. 9 There were no signifi cant differences in the total calorie intake between groups. Rats were killed 24 h after the last injection of fatty acids.…”

“…9 In that study, mucosal injury was improved by treatment with MCTs. These results suggested that MCTs modulate not only infl ammatory immune response but also intestinal barrier function.…”

“…Rats were given MCTs (tri-octanoin 8 : 0, 5 g/kg; Nihon-Yushi, Tokyo, Japan) or the same weight of corn oil by gavage daily for 2 weeks, and received food and water ad libitum throughout the study (n = 8 in each group). 9,10 The calorie intake of chow diets was 350.32 ± 1.35 Kcal/ kg per day in normal rats, 305.57 ± 1.45 Kcal/kg per day in rats given corn oil, and 306.72 ± 1.57 Kcal/kg per day in rats given MCTs. The calorie intake from the daily fat supplement was 45 Kcal/kg per day.…”

Phosphatidylcholine enrichment with medium chain fatty acids by immobilized phospholipase A1‐catalyzed acidolysis

“…6 Incorporation of saturated fatty acids with a chain length of 6-10 carbons (medium-chain fatty acid, MCFAs although sometimes dodecanoic acid is included) into PLs has led to improved heat and oxidation stability, as well as enhanced emulsifying properties. 7 Recent studies have confirmed the potential of MCFAs to reduce the following aspects: body weight, particularly body fat [8][9][10][11][12] ; lipoprotein secretion and attenuate postprandial triglyceride response 13,14 ; fasting lipid levels in serum more quickly and efficiently than oils rich in mono-or polyunsaturated fatty acids 15,16 ; intestinal injury, 17 and protect against alcohol-induced hepatotoxicity. 18 Since 1994, the use of MCFAs in food products is recognized as safe by the FDA.…”

Intestinal gene expression in pigs: effects of reduced feed intake during weaning and potential impact of dietary components

“…Since sIgA plays an important role in protection against infections in the intestinal immune system, an enhanced sIgA production is thought to be beneficial for the organism (137) . Obviously, dietary MCT can reduce intestinal injury after endotoxin administration by inhibition of the expression of some inflammatory cytokines and enhancing intestinal sIgA (136) . Furthermore, effects on intestinal gene expression have been shown in several studies investigating the anti-inflammatory effects of dietary conjugated linoleic acid (CLA) ( Table 3).…”