Anti-hyperglycemic effects and mechanism of Bidens pilosa water extract

Aim of study: Bidens pilosa has traditionally been used as an anti-diabetic phytomedicine. However, its alleged benefits and mechanism remain elusive. This study aimed to evaluate the effect and action of Bidens pilosa water extract on type 2 diabetes. Materials and methods: A daily dose of Bidens pilosa water extract or glimepiride, a positive control, was given orally to C57BL/KsJ-db/db mice once or for 28 days. Levels of blood glucose, serum insulin, and glycosylated hemoglobulin A1C, glucose tolerance, and islet structure were used to evaluate its antidiabetic effects in db/db mice. Rat pancreatic islets and streptozocin-treated mice were tested for insulin-releasing mechanism of Bidens pilosa water extract. Results: A daily dose of Bidens pilosa water extract given once or for 28 days significantly decreased blood glucose levels and increased serum insulin levels in db/db mice. Besides, 28-day treatment with Bidens pilosa water extract significantly improved glucose tolerance, decreased HbA1C levels and protected islet structure in db/db mice. Mechanism study showed that Bidens pilosa water extract stimulated insulin secretion via pancreatic islets. Conclusions: Our results suggest that Bidens pilosa water extract ameliorates type 2 diabetes in db/db mice via regulation of insulin secretion and islet protection. (C) 2009 Elsevier Ireland Ltd. All rights reserved.