title: Fucoidan from sea cucumber Cucumaria frondosa exhibits anti-hyperglycemic effects in insulin resistant mice via activating the PI3K/PKB pathway and GLUT4.
abstract: The present study investigated the anti-hyperglycemic properties and mechanisms of fucoidan, isolated from Cucumaria frondosa (Cf-FUC), in insulin resistant mice. Male C57BL/6J mice were fed regular diet or high-fat/high-sucrose diet for 19 weeks. Model animals were dietary administrated either rosiglitazone (RSG, 1 mg/kg·bw), fucoidan (Cf-FUC, 80 mg/kg·bw) or their combinations. Results showed that Cf-FUC significantly reduced fasting blood glucose and insulin levels, and enhanced glucose tolerance and insulin tolerance in insulin-resistant mice. Quantitative real-time PCR analysis showed that Cf-FUC increased the mRNA expressions of insulin receptors (IR), insulin receptor substrate 1 (IRS-1), phosphatidylinositol 3 kinase (PI3K), protein kinase B (PKB), and glucose transporter 4 (GLUT4). Western blot assays demonstrated that Cf-FUC showed no effect on total protein expression but nevertheless enhanced the phosphorylation of proteins listed above and increased translocation of GLUT4 to the cell membrane. Furthermore, Cf-FUC enhanced the effects of RSG. These results indicated that Cf-FUC exhibited significant anti-hyperglycemic effects via activating PI3K/PKB pathway and GLUT4 in skeletal muscle and adipose tissue.
authors.affiliation: College of Food Science and Engineering, Ocean University of China, 5th Yushan Road, Qingdao, Shandong Province, 266003, China.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Wang
authors.affiliation: College of Food Science and Engineering, Ocean University of China, 5th Yushan Road, Qingdao, Shandong Province, 266003, China.
authors.forename: Jingfeng
authors.initials: J
authors.lastname: Wang
authors.affiliation: College of Food Science and Engineering, Ocean University of China, 5th Yushan Road, Qingdao, Shandong Province, 266003, China.
authors.forename: Yanlei
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: College of Food Science and Engineering, Ocean University of China, 5th Yushan Road, Qingdao, Shandong Province, 266003, China.
authors.forename: Shiwei
authors.initials: S
authors.lastname: Hu
authors.affiliation: College of Food Science and Engineering, Ocean University of China, 5th Yushan Road, Qingdao, Shandong Province, 266003, China.
authors.forename: Di
authors.initials: D
authors.lastname: Shi
authors.affiliation: College of Food Science and Engineering, Ocean University of China, 5th Yushan Road, Qingdao, Shandong Province, 266003, China. Electronic address: xuech@ouc.edu.cn.
authors.forename: Changhu
authors.initials: C
authors.lastname: Xue
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D048016:Cucumaria / Q000737:chemistry*; D004032:Diet / Q000662:veterinary; D059305:Diet, High-Fat / Q000662:veterinary; D004789:Enzyme Activation / Q000187:drug effects; D005215:Fasting / Q000097:blood; D005951:Glucose Tolerance Test; D051275:Glucose Transporter Type 4 / Q000235:genetics / Q000378:metabolism*; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000097:blood; D055504:Insulin Receptor Substrate Proteins / Q000235:genetics; D007333:Insulin Resistance; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism; D058539:Phosphatidylinositol 3-Kinase / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D011134:Polysaccharides / Q000008:administration & dosage / Q000494:pharmacology*; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D011972:Receptor, Insulin / Q000235:genetics; D000077154:Rosiglitazone; D015398:Signal Transduction / Q000187:drug effects; D045162:Thiazolidinediones / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D001786:Blood Glucose; D051275:Glucose Transporter Type 4; D007004:Hypoglycemic Agents; D007328:Insulin; D055504:Insulin Receptor Substrate Proteins; D011134:Polysaccharides; C495693:Slc2a4 protein, mouse; D045162:Thiazolidinediones; D000077154:Rosiglitazone; C007789:fucoidan; D058539:Phosphatidylinositol 3-Kinase; D011972:Receptor, Insulin; D051057:Proto-Oncogene Proteins c-akt
keywords: Anti-hyperglycemic effects; Glucose transporter 4; Insulin resistance; Phosphatidylinositol 3 kinase pathway; Sea cucumber fucoidan