['Guazuma ulmifolia Lam (Sterculiaceae) is a plant extensively used in México for the empirical treatment of type 2 diabetes.', 'To investigate the anti-diabetic mechanisms of Guazuma ulmifolia.', 'Non-toxic concentrations of Guazuma ulmifolia aqueous extracts (GAE) were assayed on adipogenesis and 2-NBDglucose uptake in the murine 3T3-F442A preadipose cell line.', 'GAE added to adipogenic medium (AM) did not affect adipogenesis at any of the tested concentrations (1-70 microg/ml), whereas in AM lacking insulin GAE 70 microg/ml induced triglyceride accumulation by 23%. On the other hand, GAE 70 microg/ml stimulated 2-NBDG uptake by 40% in insulin-sensitive 3T3-F442A adipocytes and by 24% in insulin-resistant adipocytes, with respect to the incorporation showed by insulin-sensitive adipocytes stimulated with the hormone.'] Are the anti-diabetic properties of Guazuma ulmifolia Lam mediated by the stimulation of glucose uptake in normal and diabetic adipocytes without inducing adipogenesis?