Interactive Effects of Dietary Resistant Starch and Fish Oil on Short-Chain Fatty Acid Production and Agonist-Induced Contractility in Ileum of Young Rats

Abstract

We have shown independently that dietary fiber and n-3 fatty acids can affect gut function. This study investigated the interactive effects of resistant starch (RS) (as high amylose maize starch [HAMS]) and tuna fish oil on ileal contractility. Four-week-old male Sprague Dawley rats were fed 4 diets that contained 100 g/kg fat as sunflower oil or tuna fish oil, with 10% fiber supplied as alpha -cellulose or HAMS for 6 weeks. Fish oil feeding led to higher ileal n-3 fatty acid levels (mainly as DHA) and higher agonist-induced maximal contractility with an RS effect noted for carbachol. HAMS-containing diets resulted in lower colonic pH and higher total short-chain fatty acids (SCFA), but not for butyrate with fish oil. Low prostanoid responses in young rats were enhanced by fish oil independent of RS. The order of muscarinic receptor subtype responses were different compared to older rats; fish oil feeding altered the sensitivity of the M(1) receptor subtype. Although little interactive effects were demonstrated, these data suggest developmental changes in ileal receptor systems with independent effects of RS and fish oil on some bowel properties in juvenile rats.

Site Specific Delivery of Microencapsulated Fish Oil to the Gastrointestinal Tract of the Rat

“…Although not determined in this study, we have shown previously that feeding small animal models with diets supplemented with fiber or RS as Hylon VII resulted in lower colonic pH and higher total SCFA levels as acetate, propionate, and butyrate [31,49,50]. Interestingly, when the diets were supplemented with RS and fish oil, the total SCFA levels were all higher except for butyrate [35].…”

“…Frozen digesta (300 mg) from stomach, small intestine, cecum or colon or frozen tissue sections (150 mg) from the small intestine or colon were ground gently in a glass homogenizer and total lipids extracted in methanol/chloroform/water (2:4:1) (v:v:v) and separated by thin layer chromatography (TLC) and fatty acids methylated and analysed by gas liquid chromatography (GLC) as described previously [34,35]. Results are expressed as EPA, DHA, or total LC n-3 PUFA recovered as mg or as percentage of total fatty acid level or total phospholipid fatty acid level.…”

“…The delivery of fish oil and resistant starch to the large bowel where cellulases and other bacteria enzymes release the fish oil and generate SCFAs may be of benefit to indices of bowel health [19,34,35] particularly with regards to the protection from the formation of adenomas [55][56][57][58] and inflammatory bowel conditions [59,60].…”

Dietary fish oil dose‐response effects on ileal phospholipid fatty acids and contractility

“…Feeding WKY rats 5% FO high in DHA for 4 wk resulted in 9.8% total n-3 PUFA (2% EPA, 1.4% DPA, and 6.3% DHA). We have also fed SD rats similar FO at 10% and achieved 11.9% total ileal n-3 PUFA (2.8% EPA, 1.4% DPA, 7.8% DHA) (8). These experiments suggested that tissue n-3 PUFA saturates of between 5 and 10% dietary FO contain high DHA.…”

Effects of microencapsulation on the gastrointestinal transit and tissue distribution of a bioactive mixture of fish oil, tributyrin and resveratrol

“…Fish oil, butyrate, trans resveratrol and resistant starch are bioactive ingredients of interest as they all have a role in improving the health and well being of the population (Gil, 2002;Jang et al, 1997;Patten et al, 2006;Topping & Clifton, 2001). Particular focus of these benefits has been for the cardiovascular and gastrointestinal systems.…”