Features of blood serum protein spectrum and cytokine spectrum of rats with chronic carrageenan-induced intestinal inflammation

Abstract

It has been established that features of modern diet might be considered as a possible source of inflammatory diseases of gastrointestinal tract. Particular attention is paid to the role of different food additives in the development of intestinal inflammation, including the food additive E407, known as carrageenan. A model of chronic carrageenan-induced gastroenterocolitis of moderate severity has been elaborated, which allows us to study carrageenan-induced intestinal inflammation. In particular, the features of blood serum protein spectrum and cytokine spectrum in chronic carrageenan-induced intestinal inflammation are not studied. The female Wistar rats have been used for the experiment. Chronic carrageenan-induced gastroenterocolitis has been reproduced by the free access of animals to 1% solution of carrageenan in drinking water. Laboratory animals have been divided into 3 groups. Group № 1 consisted of experimental animals, who consumed food additive carrageenan during 2 weeks and group № 2 included experimental animals, who consumed food additive carrageenan during 4 weeks. Group № 3 consisted of intact healthy animals. The development of gastroenterocolitis has been proved morphologically and biochemically. Manipulations with animals have been carried out in accordance with the provisions of the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (Strasbourg, 1986). It has been established that the disease has been associated with dysproteinemia. The level of α1-globulins increased after 2 weeks of carrageenan consumption and has been normalized in animals, who consumed carrageenan during 4 weeks. The similar changes have been observed for α2-globulins level. It could be explained by production of acute phase proteins, such as α1-acid glycoprotein, C-reactive protein, fibrinogen, α2-macroglobulin, ceruloplasmin, etc. The intake of carrageenan also caused hypergammaglobulinemia that was more significant in animals of the 2nd group. The development of chronic carrageenan-induced gastroenterocolitis has been also accompanied by elevated levels of pro-inflammatory cytokines, such as TNF-α and IL-1α, and anti-inflammatory cytokine IL-4 inblood serum of rats. The elevated levels of TNF-α and IL-1α might explain observed changes of blood serum spectrum, particularly increased α1-globulins and α2-globulins. A significant increase in IL-4 content in the blood of animals with chronic carrageenan-induced gastroenterocolitis may be responsible for the increased permeability of the intestinal mucosa to luminal antigens and bacterial translocation across the intestinal wall and their subsequent influence on the pathological process.

Keywords

• carrageenan
• gastroenterocolitis
• protein spectrum
• TNF-α
• interleukins