Synthesis of Sulochrin-125I and Its Binding Affinity as α-Glucosidase Inhibitor using Radioligand Binding Assay (RBA) Method

Abstract

Most of diabetes patients have type 2 diabetes mellitus or non insulin dependent diabetes mellitus. Treatment of type 2 diabetes mellitus can be conducted by inhibiting the α-glucosidase enzyme which converts carbohydrates into glucose. Sulochrin is one of the potential compounds which can inhibit the function of α-glucosidase enzyme. This study was carried out to obtain data of sulochrin binding with α-glucosidase enzyme as α-glucosidase inhibitor using Radioligand Binding Assay (RBA) method. The primary reagent required in RBA is the labeled radioactive ligand (radioligand). In this study, the radioligand was sulochrin-¹²⁵I. Prior to the sulochrin-¹²⁵I synthesis, sulochrin-I was synthesized. Sulochrin-I and sulochrin-¹²⁵I were synthesized and their bindings were studied using RBA. The  molecular formula of the synthesized Sulochrin-I is C₁₇H₁₅O₇I and its molecular weight is 457.9940. The sulochrin-¹²⁵I was synthesized from sulochrin-I by isotope exchange method. From RBA, the dissociation constant (K_d) and the maximum binding (B_max) were found as 26.316 nM and 9.302 nM, respectively. The low K_d indicates that sulochrin is capable of binding to α-glucosidase.

Received: 08 November 2013; Revised: 28 February 2014; Accepted: 28 March 2014