Effects Of Bovine Colostrums Insulin-like Growth Factor-Ⅰ Extraction On The Proliferation Of Human Intestinal Caco-2 Cell Line And The Recovery Of Intestinal Mucositis

The injury of gastrointestinal mucosa and epithelial is common in clinical, serious mucosal can cause systemic dysfunction on pathology, physiology and visceral. colostrum insulin-like growth factor-I (IGF-I) as a kind of active peptide substances is similar with insulin on molecular structure, which is abundance in bovine colostrum, and is the most important growth factors. In this study, to understand the role of IGF-I on the repair of gastrointestinal injury by vitro and vivo experiments.Take bovine colostrums as raw material, methods IGF-Ⅰwas purfied by ultrafiltration, ion exchange chromatography. This study explored the repair of colostrum IGF-Ⅰextraction on intestinal mucosal by vitro and vivo experments. In vitro, this article researched effect of colostum IGF-Ⅰextraction by measuring the impacts on CaCO-2 cell proliferation; in vivo, enteritis was induced in rats through peritoneal injection of methotrexate (20μg/kg). The experimental animals were randomly divided into four groups: normal group, MTX model group (20μg/kg), bovine colostrum IGF-I extraction recovery group (75μg/kg) and IGF-I recovery group (75μg/kg). The last two groups were administered in corresponding groups by gastric irrigation daily for 5 days, and the administered time had been from 2nd day to 5th day, the normal group and MTX model group were administered with Physiological Saline. The rats were died on 3nd and 6nd, Plasma diamine oxidase (DAO) and D-lactate level were measured, and histological changes in intestinal tissue were observed under the light microscope.In vitro, the rusults showed that CaCO-2 cell proliferation is gradually increased by the increased concentration of IGF-Ⅰextraction , when the concentration of IGF-Ⅰextraction exceed a certain concentration(100ng/mL), the proliferation is saturated. The cell model was treated by IGF-Ⅰextraction(100ng/mL), which had a significantly proliferation on the damaged CaCO-2 cell(P<0.01). In vivo, The results showed that the activity of DAO and D-lactate level of MTX model group were significantly increased compared with normal group on 3nd (P<0.01), and intestine injury was deeper than the normal group (P<0.01). The activity of DAO and D-lactate level of bovine colostrum IGF-I extraction recovery group were significantly decreased on 6 nd compared with model group on 6 nd and recovery group (P<0.01), and intestine injury was lighter than the normal group (P<0.01).The results of this study showed that colostrum IGF-I extract had significant proliferation promoting effect on human intestinal cells CaCO-2. When its concentration exceeded 100ng/mL, cell proliferation effect became saturated and did not indicate inhibitation effect. The colostrum IGF-Ⅰextract showed certain protective effect on the permeability of bowel mucosa and could reduce the inflammatory cells infiltration. The relationship between IGF-Ⅰand intestinal mucosa damage repair and wound healing was investigated in this research in order to develop new medicines which could deal with intestinal mucosa damage or wound healing quickly.