Mineralization Profile of Annexin A6-Harbouring Proteoliposomes: Shedding Light on the Role of Annexin A6 on Matrix Vesicle-Mediated Mineralization

Author(s):Show less -

Veschi, Ekeveliny Amabile ; Bolean, Mayte ; da Silva Andrilli, Luiz Henrique ; Sebinelli, Heitor Gobbi ; Strzelecka-Kiliszek, Agnieszka ; Bandorowicz-Pikula, Joanna ; Pikula, Slawomir ; Granjon, Thierry ; Mebarek, Saida ; Magne, David ; Millan, Jose Luis ; Ramos, Ana Paula ; Buchet, Rene ; Bottini, Massimo ; Ciancaglini, Pietro

• Document type: Journal article
• Source: INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES; v. 23, n. 16, p. 15-pg., 2022-08-01.

Abstract

The biochemical machinery involved in matrix vesicles-mediated bone mineralization involves a specific set of lipids, enzymes, and proteins. Annexins, among their many functions, have been described as responsible for the formation and stabilization of the matrix vesicles ' nucleational core. However, the specific role of each member of the annexin family, especially in the presence of type-I collagen, remains to be clarified. To address this issue, in vitro mineralization was carried out using AnxA6 (in solution or associated to the proteoliposomes) in the presence or in the absence of type-I collagen, incubated with either amorphous calcium phosphate (ACP) or a phosphatidylserine-calcium phosphate complex (PS-CPLX) as nucleators. Proteoliposomes were composed of 1,2-dipalmitoylphosphatidylcholine (DPPC), 1,2-dipalmitoylphosphatidylcholine: 1,2-dipalmitoylphosphatidylserine (DPPC:DPPS), and DPPC:Cholesterol:DPPS to mimic the outer and the inner leaflet of the matrix vesicles membrane as well as to investigate the effect of the membrane fluidity. Kinetic parameters of mineralization were calculated from time-dependent turbidity curves of free Annexin A6 (AnxA6) and AnxA6-containing proteoliposomes dispersed in synthetic cartilage lymph. The chemical composition of the minerals formed was investigated by Fourier transform infrared spectroscopy (FTIR). Free AnxA6 and AnxA6-proteoliposomes in the presence of ACP were not able to propagate mineralization; however, poorly crystalline calcium phosphates were formed in the presence of PS-CPLX, supporting the role of annexin-calcium-phosphatidylserine complex in the formation and stabilization of the matrix vesicles' nucleational core. We found that AnxA6 lacks nucleation propagation capacity when incorporated into liposomes in the presence of PS-CPLX and type-I collagen. This suggests that AnxA6 may interact either with phospholipids, forming a nucleational core, or with type-I collagen, albeit less efficiently, to induce the nucleation process. (AU)

• FAPESP's process: 19/25054-2 - Strontium-containing nanoparticles and their versatility for biomaterials fabrication: implications and applications in biomineralization
• Grantee: Ana Paula Ramos
• Support Opportunities: Regular Research Grants
• FAPESP's process: 21/13140-1 - Study of PHOSPHO1 and nSMase2 interaction with model membranes: a possible correlation in matrix vesicle secretion
• Grantee: Luiz Henrique da Silva Andrilli
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 17/20846-2 - Exploring the role of lipid-protein-mineral matrix on bone biomineralization: a biophysical approach using self-assembled films
• Grantee: Marcos Antonio Eufrásio Cruz
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 19/08568-2 - Investigation of the extracellular vesicles (VEs) role in the initiation, propagation, regeneration, and modeling of biological mineralization
• Grantee: Pietro Ciancaglini
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 22/05026-7 - Training in the isolation of extracellular vesicles (EVs) and MVs modeling biological mineralization
• Grantee: Heitor Gobbi Sebinelli
• Support Opportunities: Scholarships in Brazil - Technical Training Program - Technical Training