Pasteurized Chicken Egg Powder Stimulates Proliferation and Migration of AGS, RIE1, and Caco-2 Cells and Reduces NSAID-Induced Injury in Mice and Colitis in Rats

Abstract

Chicken eggs and bovine colostrum contain proteins possessing antimicrobial, immunoregulatory, and growth factor activity. The ability of eggs to influence gut defense and repair is largely unexplored. We examined the effect of pasteurized spray-dried egg on gastrointestinal injury using cell culture and animal models and sought to determine whether adding colostrum provided extra benefit. Egg alone, colostrum alone, and a 40:60 egg: colostrum combination were tested for proliferative (Alamar blue) and migratory (wounded monolayer) activity at 1 mg.mL-1 using human colon adenocarcinoma (Caco-2), human gastric cancer (AGS), and rat intestinal epithelioid-1 (RIE1) cells. Four groups of adult male C57BL/6 mice received 20 mg.kg-1.d-1 test products in drinking water for 7 d and indomethacin (85 mg.kg-1, administered subcutaneously) on day 7. Villus height and morphology were assessed. Three groups of adult male Sprague Dawley rats received 20 mg.kg-1.d-1 test product by gavage for 9 d and dextran sodium sulfate (DSS, 4% in drinking water) for the final 7 d. Histology, microscopic damage scoring, and myeloperoxidase were assessed. Egg or colostrum alone caused 3-fold increases in cell proliferation and migration (P<0.05 compared with baseline). Heating the egg removed its bioactivity. Addition of neutralizing antibodies or tyrphostin showed that ovomucoid, ovalbumin, and the epidermal growth factor receptor mediated the effects of egg (all P<0.05 compared with egg). Egg reduced shortening of villi caused by indomethacin in mice by 34% and reduced DSS-induced colonic damage in rats by 44-61% (P<0.05 compared with DSS). Similar results were seen using colostrum alone. In each assay, the 40:60 combination gave improved results compared with the same dose of egg or colostrum alone (P<0.05). Studies using AGS, RIE1, and Caco-2 cells, C57BL/6 mice, and Sprague Dawley rats showed protective effects of egg against gut injury. Enhanced results were seen if colostrum and egg were coadministered. Egg powder with or without colostrum may have therapeutic value for prevention and treatment of gut injuries.