CHEMICAL CHARACTERIZATION OF DIABETIC HERBAL TEA AND IN VITRO EVALUATION OF GLUCOSE TRANSPORT AND METABOLISM GENE EXPRESSION PROFILE

Diabetes or diabetes mellitus is probably the world’s largest growing disorder. It is a chronic disorder of glucose (sugar) metabolism caused by inadequate production or use of the hormone, insulin. Type 2 diabetes is characterized by hyperglycemia coupled with insulin resistance and relative insulin deficiency. Over 1,200 species of plants have been reported to be used ethnopharmacologically or experimentally in the treatment of diabetes. Brickellia, a member of the Asteraceae family and native to Mexico and the south-western portion of the United States, is the focus of our research program. Species of the Asteraceae family are used largely for their presumed antidiabetic and anticancer properties among others. Brickellia is consumed orally; therefore the liver is the first target organ of exposure and the primary interface in the regulation of glucose metabolism. For this study we investigated the herbal plant extracts of Brickellia cavanillesii for its potential in glucose transport and metabolism in the prevention and control of diabetes. We tested the central hypothesis that whole herbal tea extracts of Brickellia alters gene expression and regulates glucose transport proteins of liver cells. To test this hypothesis we:

1. Isolated the individual fractions of the herbal tea extracts of Brickellia cavanillesii using gas chromatographic methods.
2. Determined using in vitro techniques the dose- and time- dependent cytotoxicity of the herbal tea extracts of Brickellia cavanillesii in human carcinoma liver cells (HepG2) in the absence and presence of Fetal Bovine Serum (FBS).3. Characterized the effects of Brickellia cavanillesii on glucose transporter (GLUT 2) in human carcinoma liver cells (HepG2) via gene and protein analysis using Western blot and Reverse-Transcriptase Polymerase Chain Reaction (RT2-PCR).
3. Validated pathway specific gene expression following exposure of HepG2 cells to Brickellia cavanillesii by quantitative gene expression analysis using real time PCR (RT2-qPCR) array. The purpose of this study was to chemically characterize and validate the potential of Brickellia cavanillesii effects on glucose transport and metabolism. It is hoped that the results generated will promote the use of Brickellia cavanillesii as a complementary and alternative agent in the therapy of Type 2 diabetes.