[Basic Studies Focusing on Lysophosphatidic Acids for Creative Food Supplements]

Our early study showed the vasoactive effects of soybean lecithin-derived lysophosphatidic acid (LPA). The finding indicates that the oral administration of LPA-rich supplements is beneficial to human health. Our studies have showed five beneficial effects of LPA in the upper digestive systems. First, we detected LPA at high levels in various herbs used in Chinese traditional medicine for the treatment of gastric ulcers, as well as other foods, including various vegetables. Second, we found human mixed saliva to be an LPA-rich biological fluid, suggesting its protective effect on human oral mucosa. Third, LPA levels in gingival crevicular fluid from patients with periodontitis was lower than that in healthy subjects, reinforcing the protective quality of LPA. Fourth, daily topical injections of LPA in rat buccal gingiva reduced the degree of alveolar bone absorption induced by oral bacteria in rats with experimental periodontitis. Fifth, repeated intragastric administration of LPA-rich herb reduced the degrees of gastric ulcer induced by stress (rats) or medication (mouse). Previous findings on the beneficial effects of LPA acting on the lumen side of the lower digestive tracts in mammals are well documented, although results on the harmful effects of LPA on mouse and rats with genetically easy to progress colon cancer are noted. Our studies also showed a novel pathway of LPA generation by lysophospholipase D activity of glycerophosphodiesterase 7 on the lumen side of digestive tracts. These findings suggest that additional research into creative food supplements focusing on LPA as a food factor could be beneficial.