title: Ursolic acid enhances the cellular immune system and pancreatic beta-cell function in streptozotocin-induced diabetic mice fed a high-fat diet.
abstract: This study investigated the effects of ursolic acid on immunoregulation and pancreatic beta-cell function in type 1 diabetes fed a high-fat diet for 4 weeks. Male mice were divided into non-diabetic, diabetic control, and diabetic-ursolic acid (0.05%, w/w) groups, which were fed a high-fat (37% calories from fat). Diabetes was induced by injection of streptozotocin (200 mg/kg B.W., i.p.). Ursolic acid significantly improved blood glucose levels, glucose intolerance, and insulin sensitivity compared to the diabetic group. The plasma insulin and C-peptide concentrations were significantly higher in the diabetic-ursolic acid group than in the diabetic group. Ursolic acid significantly elevated the insulin levels with preservation of insulin staining of beta-cells in the pancreas. In splenocytes, concanavalin (Con) A-induced T-cell proliferation was significantly higher in the diabetic-ursolic acid group compared to the diabetic group, but liposaccharide (LPS)-induced B-cell proliferation did not differ between groups. Ursolic acid enhanced IL-2 and IFN-gamma production in response to Con A stimulation, whereas it inhibited TNF-alpha production in response to LPS stimulation. In this study, neither streptozotocin nor ursolic acid had effects on lymphocyte subsets. These results indicate that ursolic acid exhibits potential anti-diabetic and immunomodulatory properties by increasing insulin levels with preservation of pancreatic beta-cells and modulating blood glucose levels, T-cell proliferation and cytokines production by lymphocytes in type 1 diabetic mice fed a high-fat diet.
authors.affiliation: Department of Nutrition Education, Graduate School of Education, Sunchon National University, Suncheon 540-742, Republic of Korea.
authors.forename: Sun-Mi
authors.initials: SM
authors.lastname: Jang
authors.forename: Sung-Tae
authors.initials: ST
authors.lastname: Yee
authors.forename: Jina
authors.initials: J
authors.lastname: Choi
authors.forename: Myung-Sook
authors.initials: MS
authors.lastname: Choi
authors.forename: Gyeong-Min
authors.initials: GM
authors.lastname: Do
authors.forename: Seon-Min
authors.initials: SM
authors.lastname: Jeon
authors.forename: Jiyoung
authors.initials: J
authors.lastname: Yeo
authors.forename: Myung-Joo
authors.initials: MJ
authors.lastname: Kim
authors.forename: Kwon-Il
authors.initials: KI
authors.lastname: Seo
authors.forename: Mi-Kyung
authors.initials: MK
authors.lastname: Lee
mesh_terms: D000276:Adjuvants, Immunologic; D000818:Animals; D000954:Antigens, Surface / Q000096:biosynthesis; D001786:Blood Glucose / Q000378:metabolism; D002096:C-Peptide / Q000097:blood; D016207:Cytokines / Q000096:biosynthesis; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy*; D004032:Diet; D004041:Dietary Fats / Q000494:pharmacology*; D019587:Dietary Supplements; D005951:Glucose Tolerance Test; D006943:Hyperglycemia / Q000097:blood / Q000188:drug therapy; D007004:Hypoglycemic Agents; D007111:Immunity, Cellular / Q000187:drug effects*; D007150:Immunohistochemistry; D007328:Insulin / Q000097:blood / Q000378:metabolism; D050417:Insulin-Secreting Cells / Q000502:physiology*; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D010179:Pancreas / Q000187:drug effects / Q000378:metabolism; D010186:Pancreatic Function Tests; D014315:Triterpenes / Q000494:pharmacology*; D000097245:Ursolic Acid
chemical_list: D000276:Adjuvants, Immunologic; D000954:Antigens, Surface; D001786:Blood Glucose; D002096:C-Peptide; D016207:Cytokines; D004041:Dietary Fats; D007004:Hypoglycemic Agents; D007328:Insulin; D014315:Triterpenes; D000097245:Ursolic Acid