Fatty acid composition and arachidonic acid concentrations in alveolar bone of rats fed diets with different lipids

Abstract

The purpose of the present study was to determine if the type of dietary fat can modify the fatty acid composition and arachidonic acid levels in the alveolar bone phospholipids. Three groups of rats were fed nutritionally adequate semipurified diets containing different lipids: 10% corn oil (control, group I, rich in n-6 fatty acids); 9% butter + 1% corn oil (experimental, group II, rich in saturated fatty acids); and 9% ethyl ester concentrate of n-3 fatty acids + 1% corn oil (experimental, group III, rich in n-3 fatty acids). After 10 weeks of feeding the various diets, rats were killed, maxillae and mandibles were dissected out, and the soft tissue was removed. Bone was frozen in liquid nitrogen and pulverized. Powdered bone was extracted for total lipids, and phospholipids were isolated by column chromatography. The fatty acid composition and arachidonic acid concentrations were determined in total phospholipids after the addition of an internal standard, octadecatetraenoic acid (18:4n-3), and subsequent gas chromatography. The type of dietary lipids had a profound influence on the fatty acid composition of bone lipids. Arachidonic acid concentrations were significantly lower in total phospholipids of mandibles and maxillae of rats fed the experimental diets than in those fed the control diet. Because arachidonic acid is a precursor of prostaglandin E2 and leukotriene C4, a significant reduction in its concentration may result in reduced levels of these eicosanoids in the alveolar bone.

Dental Resorptions and their Challenge: Three Case Reports

“…The work of Alam et al [2] evaluated the fatty composition of arachidonic acid in the alveolar bone of laboratorial rats and concluded that specific dietary lipids altered the fatty acid composition of bone lipids, and added that diets enriched with fish oil decreased the concentration of arachidonic acid by diminishing the amount of osteoclasts in the area investigated. Arachidonic acid can be converted to series 2 prostaglandins or to series 4 leukotriens by ciclooxy-genase pathways.…”

High Saturated Fat Diet Alters the Lipid Composition of Triacylglycerol and Polar Lipids in the Femur of Dam and Offspring Rats

“…These dietary-mediated changes in femur lipids following high n-3 or n-6 PUFA or low ratio of n-6:n-3 PUFA diets results in stronger bones [1], increased bone formation rates [3,7], higher bone mineral content [5], and higher bone mineral density [3,5,7,8]. Interestingly, bone lipids influenced by dietary ratio of n-6:n-3 PUFA included polar (PL; associated with cellular membranes) and/or neutral [common storage form of lipids, or specifically triacylglycerols (TAG)] measured in femur and alveolar bones [3][4][5]. The bone lipid pool affected is of interest as it has been suggested that a greater amount of n-3 PUFA in bone cell membranes may reduce the availability of n-6 PUFA, specifically arachidonic acid, and thereby attenuate osteoclastogenesis [9].…”

“…Alternatively, high n-3 and n-6 PUFA diets (20 % by weight for 65 days) [1], or differing ratios of n-6:n-3 PUFA (7-10 % by weight for 6-10 weeks) [3][4][5], resulted in lower SFA and higher PUFA in the femur of developing male rats. These dietary-mediated changes in femur lipids following high n-3 or n-6 PUFA or low ratio of n-6:n-3 PUFA diets results in stronger bones [1], increased bone formation rates [3,7], higher bone mineral content [5], and higher bone mineral density [3,5,7,8].…”

“…Bone fatty acid composition is altered by the type and amount of fatty acids consumed in developing rodents [1][2][3][4][5]. Specifically, high saturated fatty acid (SFA) diets (10-20 % SFA source by weight fed for 9-17 weeks) result in lower amounts of n-3 polyunsaturated fatty acids (PUFA) or n-6 PUFA in the femur [1,2] and alveolar bone [4] of developing male and female rats.…”

“…Specifically, high saturated fatty acid (SFA) diets (10-20 % SFA source by weight fed for 9-17 weeks) result in lower amounts of n-3 polyunsaturated fatty acids (PUFA) or n-6 PUFA in the femur [1,2] and alveolar bone [4] of developing male and female rats. However, high SFA diets that are thought to alter bone total lipid composition have either no effect [1] or a negative effect [6] on bone mineral content and/or density in 7-15 week old male and female rats.…”