In addition, over-expressed APP gene expression by high-fat diet in small intestine may contribute to the chronically increased level of plasma Aâ peptide and may increase bidirectional transfer of Aâ through the blood-brain barrier, which may exacerbate lipid metabolism and amyloidosis in the brain. The aim of this study was to investigate the influence of APP gene expression in the duodenum by aging, dietary fat and diabetes. Methods: To measure APP gene expression in the intestine,
the duodenum was obtained from C57BL/6 male mice fed on normal chow or high-fat diet. Mice were sacrificed at 16 and 26 weeks of age for ABC294640 purchase both dietary groups. In addition, about 15 mice from each group were treated with streptozotocin to induce diabetes and the duodenum was obtained at 16 and 26 weeks
of age 5 weeks after streptozotocin treatment. Total RNA was extracted using duodenum samples from 7 to 15 mice of 8 different groups on different conditions (at 16 vs. 26 weeks of age / diabetic vs. non-diabetic / on normal chow vs. LGK-974 datasheet high-fat diet). Results: Mice fed on high-fat diet (HFD) showed increased body weight compared to mice of normal chow (ND) at 6 weeks of age one week after beginning of HFD feeding (p<0.05). Streptozotocin-induced diabetic mice decreased body weight (p<0.05). While APP gene expression in the small intestine was not changed in the normal diet group mice between mice at 16 and 26 weeks of age, the APP gene expression was significantly increased by aging in HFD group (p<0.05). The
effect of HFD on APP expression was not observed in bothage groups, 16 weeks and 26 weeks of age (p=0.2). APP was significantly down-regulated in streptozotocin-induecd diabetic mice (hypoinsulinemia and hyperglycemia) fed on normal chow at 16 weeks of age (p<0.05). APP gene expression, ADP ribosylation factor however, was not significantly changed by streptozotocin treatment in mice fed on HFD at 16 weeks of age and fed on ND at both 16 and 26 weeks of age. Conclusion: APP gene expression in the small intestine was observed to be increased in the aged, high fat diet induced obese mice. The effects on systemic Aâ levels and lipid metabolism and/or amyloidosis needs to be further investigated. Results of this study provide important information to the research of Aâ/amyloidosis pathology Key Word(s): 1. high-fat diet ; 2. APP; 3. duodenum ; Presenting Author: YAO JIAYIN Additional Authors: ZHI MIN, GAO XIANG, HU PINJIN, LI CHUJUN, YANG XIAOBO Corresponding Author: YAO JIAYIN Affiliations: The Sixth Affiliated Hospital of Sun Yat-Sen University Objective: Our previous study has shown that reduced insulin resistance (IR) was one of the possible mechanisms for the therapeutic effect of silibinin on non-alcoholic fatty liver disease (NAFLD) in rats. In the present study, we investigated the pathways of silibinin in regulating hepatic glucose production and IR amelioration.