Background: Type 2 diabetes mellitus can be defined as a conformational disease because in which a constituent beta cell protein, islet amyloid polypeptide (amylin), undergoes a change in tertiary structure followed by a self-association. In this research, Lead (Pb) and Zinc effects in the aggregation of the amylin was examined experimentally.

Materials and Methods: Human amylin peptide and other chemicals were purchased from Sigma-Aldrich Company. Aggregation was induced by adding stock solution to modified Krebs-Hensleit buffer (pH: 7.4) to a final concentration of 0.4 μM and incubated at 37oC for 144h. Zinc (50 μM) and Pb (10 μM) was prepared in the peptide containing solution, separately. Also a mixture of trace elements and amylin with the same concentration was prepared. The zinc and Pb free solution was selected as control. To monitor the peptide precipitation Thioflavin T fluorescence assay was performed.

Results: The results showed that zinc increased amylin aggregation by 12.31 % (P<0.05) and Pb enhanced aggregation potential by 23.17 % (P<0.05). A combination of Zn and Pb increased amylin aggregation by 0.24% compared to Pb group.

Conclusion: Under the experimental conditions, Pb and Zinc separately have permissive effects on formation of beta-amyloid sheet. However, pb along with Zinc has no synergistic effect on aggregation of amylin.