Wax bean agglutinin (WBA) was found to mimic the activities of insulin in mediating glucose oxidation and antilipolysis. In contrast, soybean and peanut agglutinins do not exert any of these activities. Unlike concanavalin A and wheat germ agglutinin that were reported previously to exhibit insulin-like activites, WBA neither enhances nor competes with the [125I]insulin binding at relatively high concentrations. Moreover, mild trypsinization of adipocytes, a treatment which greatly diminishes the binding and bioactivity of insulin in fat cells, only slightly affects glucose oxidation induced by WBA. ED50 values for WBA mediated glucose oxidation and antilipolysis are 9.3 μg and 40.0 μg, respectively, compared with the nearly identical concentrations required for 50% of maximal effect of both glucose oxidation and antilipolysis, mediated by wheat germ agglutinin. The present studies suggest that these two activities may be triggered by WBA via surface glycoproteins that are distinct from the binding site of insulin.
|Number of pages||7|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - 30 Jan 1981|