title: The Involvement of Serotonin in the Hypoglycemic Effects Produced by Administration of the Aqueous Extract of Xylaria nigripes with Steroid-Induced Insulin-Resistant Rats.
abstract: Xylaria nigripes (XN) is a medicinal fungus with a high-economic value. The aim of this study was to explore the hypoglycemic effects and mechanisms of the XN aqueous extract in steroid-induced insulin-resistant (SIIR) rats. Significant hypoglycemic effects were observed 60 min after administration of XN aqueous extract. In normal Wistar, hypoglycemic effects were 21% (the plasma glucose level decreased from 128.6 ± 12.5 to 100.9 ± 10.7 mg/dL). In SIIR, hypoglycemic effects were 26% (the plasma glucose level decreased from 177.6 ± 12.5 to 133.3 ± 29.7 mg/dL) rats refer to their baseline. The signaling proteins for insulin-receptor substrate-1 and glucose transporter-4 increased 0.51-fold and 1.12-fold, respectively, as determined by Western blotting; the increase in the proteins was 13% and 9%, respectively, as determined by immunohistochemistry. The serotonin antagonist, α-p-chlorophenylalanine, effectively blocked the hypoglycemic effects and increased the signaling protein levels. After XN administration, none of the animals showed significant changes in plasma-free fatty acids in 60 min. In summary, the XN extract may have hypoglycemic effects in normal Wistar and SIIR rats that may have a serotonin-related hypoglycemic effect and enhance insulin sensitivity in the SIIR rats.
authors.affiliation: Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: Ying-I
authors.initials: YI
authors.lastname: Chen
authors.forename: Chung-Yuh
authors.initials: CY
authors.lastname: Tzeng
authors.forename: Yu-Wen
authors.initials: YW
authors.lastname: Cheng
authors.forename: Tai-Hao
authors.initials: TH
authors.lastname: Hsu
authors.forename: Wai Jane
authors.initials: WJ
authors.lastname: Ho
authors.forename: Zeng-Chin
authors.initials: ZC
authors.lastname: Liang
authors.forename: Chang-Wei
authors.initials: CW
authors.lastname: Hsieh
authors.forename: Jason T C
authors.initials: JT
authors.lastname: Tzen
authors.forename: Shih-Liang
authors.initials: SL
authors.lastname: Chang
mesh_terms: D000818:Animals; D001688:Biological Products / Q000494:pharmacology*; D001786:Blood Glucose / Q000187:drug effects; D005230:Fatty Acids, Nonesterified / Q000097:blood; D010134:Fenclonine / Q000494:pharmacology; D051275:Glucose Transporter Type 4 / Q000378:metabolism; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000097:blood; D055504:Insulin Receptor Substrate Proteins / Q000378:metabolism; D007333:Insulin Resistance; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D012702:Serotonin Antagonists / Q000494:pharmacology; D013098:Xylariales / Q000737:chemistry*
chemical_list: D001688:Biological Products; D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D051275:Glucose Transporter Type 4; D007004:Hypoglycemic Agents; D007328:Insulin; D055504:Insulin Receptor Substrate Proteins; C526296:Irs1 protein, rat; D012702:Serotonin Antagonists; C495694:Slc2a4 protein, rat; D012701:Serotonin; D010134:Fenclonine
keywords: Xylaria nigripes; insulin resistance; plasma glucose; serotonin; steroid