Digestive Lipases by Orlistat

Studies of the partitioning of orlistat between the micellar and oil phases were performed at our laboratory [52, 110]. Even in the presence of bile salts, orlistat was found to be mostly associated with the oil phase. This interesting physicochemical property is probably a requirement for prototypic lipase inhibitors to be effective under physiological conditions, i.e. in the presence of bile and dietary lipids. 

Based on in vitro studies, it was reported that bile salts above their critical micellar concentrahon (CMC) are required for orlislal to be able to effectively inhibit HPL [29] and lipoprotein lipase [111]. The fact that the inhibited HPL could be reactivated by reducing the bile salt concentration below its CMC suggested that bile salts (above their CMC) may stabilize the acyl-hpase complex [29]. 

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