Antidiabetic properties of selected Mexican copalchis of the Rubiaceae family

The extracts prepared from the stem barks of several Mexican copalchis (Hintonia latiflora, Exostema caribaeum and a commercial mixture of Hintonia standleyana and E. caribaeum) showed significant (p < 0.05) antihyperglycemic effects. From H. latiflora, the cucurbitacin 1, and several other known compounds, were isolated. Oral administration of H. latiflora extract [100 mg/kg] and 5 (30 mg/kg) to STZ-diabetic rats over a 30 day duration restored normal blood glucose levels. It was also demonstrated that the extract of H. latiflora regulated hepatic glycogen and plasma insulin levels.