Investigation of Mg(II)-insulin interactions for detection of aggregated species and development of new formulations

• Grant number: 21/14503-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2022
• End date: November 30, 2023
• Field of knowledge: Biological Sciences - Biophysics - Biophysics of Processes and Systems
• Principal Investigator: Rose Maria Carlos
• Grantee: Denize Maria Silva e Silva
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The aggregation processes of amyloid proteins in vivo are associated with the pathogenesis of several incurable neurologic diseases and in vitro they preclude or shows limitations both in storage and therapeutic applications such as on the biopharmaceutical protein insulin. However, stabilizing this conformation has disadvantages, since insulin is active in the monomeric form and dissociation of the hexamers is slow, which leads to delayed absorption. Fast-acting formulations stabilize the monomeric form, but these also present problems due to the tendency of the monomeric conformation to aggregate. The studies carried out so far show that the choice of excipients in the information defines the preferential conformation and pharmacokinetics with transfer in insulin absorption and time of action (beginning, peak and end). In this project we intend to prepare Mg(II) complex containing phenols (mangiferin, ferulic acid) in the evaluation sphere and evaluate the influence and full effect of Mg(II), absorption and dissociation kinetics of insulin. Mg(II) complexes were designed to interact with insulin in a reversible way through non-covalent interactions that can provide a faster dissociation to the active monomeric form. As well as Zn (II) the Mg (II) ion is an essential element to the organism participating in several biological processes and that is why a daily intake of 200-400 mg is recommended. Mg(II) has a radius similar to Zn(II) and both form closed-layer complexes. Ferulic acid and mangiferin have anti-inflammatory and antioxidant activity, in addition to beneficial effects on the lipid profile and on glucose homeostasis. The intense fluorescence of the proposed Mg(II) complexes in the visible region allows the monitoring of the insulin aggregation process and complex-insulin interaction in real time by conventional fluorescence techniques. To evaluate the Mg(II)-insulin complex interaction we intend to investigate (1) the antioxidant and antimicrobial activity of the proposed complexes (2) insulin aggregation kinetics in the absence and presence of the complexes, obtaining dissociation constants and stoichiometry of the insulin interaction -complex (3) Diffusion coefficient resulting from insulin-complex interaction in different states of insulin aggregation (4) interaction of insulin with mimetic models of eukaryotic and mammalian cell membrane in the absence and presence of complexes. The studies proposed for this project are included in the regular FAPESP project (2019-21143-0) by Professor Rose Maria Carlos