Background and aim: increasing efforts are focusing on the development on new engineered surfaces that mimic the extracellular matrix (ECM) properties in order to boost β-cell differentiation and functions in vitro. We have recently demonstrated that mouse and human β-cells sense and respond to the ECM nanotopography by activating a mechanotransductive pathway, which mainly induces a reorganization of the cytoskeleton. Since mitochondria are connected to the cytoskeleton and play a pivotal role in regulating β-cells survival and function, aim of the proposed research was to evaluate whether extracellular nanotopography may affect mitochondrial dynamics, thus driving β-cell fate. Materials and Methods: mouse β-cells were seeded on nanostructured zirconia films with controlled nanoscale morphology, produced by the supersonic clusters beam deposition (SCBD) technique. Changes in mitochondrial proteins were identified by a shotgun label-free proteomic approach performed on a mitochondrial sub-fractionation. Mitochondrial morphology and dynamics were evaluated by means of super-resolution fluorescence microscopy. Results: Proteomic analyses revealed modifications in the expression of proteins involved in mitochondrial dynamics, cristae formation and shaping (OPA1, ATP5A1, CHCHD3, IMMT, LETM1, SAMM50, MICOS 19, 60, 10) in cells grown on the nanostructure. Reorganization of mitochondrial morphology were confirmed by quantitative immunofluorescence analyses which showed elongated mitochondria with increased dimension in cells grown on the nanostructure. A significantly increased in the mitochondrial membrane potential was detected in cells grown on the nanostructure compared to flat substrates. Interestingly, the mitochondrial proteome revealed also the up-regulation of proteins involved in vesicle-mediated transports in combination with a reduction of proteins shared by the endoplasmic reticulum (ER) and mitochondria (CRPX, GRPEL1, HSPD1, DNAJA1, HSPA5, HSPA9, TRAP1), suggesting that the nanostructure alters the protein network involved in the complex interplay between ER and mitochondria in cells grown on the nanostructure. Accordingly, morphological analyses showed a profound reorganization of the mitochondrial-ER connection sites. Conclusions: our results indicate that extracellular nanotopography influences mitochondrial function and morphology, as well as their interplay with other organelles, which is crucial for matching the metabolic needs of the cells. Since mitochondria provide both the energy for cell survival and the signals for efficient glucose-dependent insulin secretion in β-cells, these findings are particularly relevant to successfully engineer scaffolds in order to improve β-cell function and viability in vitro.

Mechanotransduction impacts beta cell function by tuning mitochondrial dynamics / A. Galli, E. Maffioli, A. Marku, S. Ghislanzoni, P. Marciani, P. Milani, C. Lenardi, G. Tedeschi, C. Perego. - In: DIABETOLOGIA. - ISSN 0012-186X. - 63:(2020 Aug 25), pp. 388.S192-388.S192. ((Intervento presentato al 56. convegno EASD Annual Meeting of the European Association for the Study of Diabetes nel 2020.

Mechanotransduction impacts beta cell function by tuning mitochondrial dynamics

A. Galli
Primo
;
E. Maffioli
Secondo
;
A. Marku;S. Ghislanzoni;P. Marciani;P. Milani;C. Lenardi;G. Tedeschi
Penultimo
;
C. Perego
Ultimo
2020-08-25

Abstract

Background and aim: increasing efforts are focusing on the development on new engineered surfaces that mimic the extracellular matrix (ECM) properties in order to boost β-cell differentiation and functions in vitro. We have recently demonstrated that mouse and human β-cells sense and respond to the ECM nanotopography by activating a mechanotransductive pathway, which mainly induces a reorganization of the cytoskeleton. Since mitochondria are connected to the cytoskeleton and play a pivotal role in regulating β-cells survival and function, aim of the proposed research was to evaluate whether extracellular nanotopography may affect mitochondrial dynamics, thus driving β-cell fate. Materials and Methods: mouse β-cells were seeded on nanostructured zirconia films with controlled nanoscale morphology, produced by the supersonic clusters beam deposition (SCBD) technique. Changes in mitochondrial proteins were identified by a shotgun label-free proteomic approach performed on a mitochondrial sub-fractionation. Mitochondrial morphology and dynamics were evaluated by means of super-resolution fluorescence microscopy. Results: Proteomic analyses revealed modifications in the expression of proteins involved in mitochondrial dynamics, cristae formation and shaping (OPA1, ATP5A1, CHCHD3, IMMT, LETM1, SAMM50, MICOS 19, 60, 10) in cells grown on the nanostructure. Reorganization of mitochondrial morphology were confirmed by quantitative immunofluorescence analyses which showed elongated mitochondria with increased dimension in cells grown on the nanostructure. A significantly increased in the mitochondrial membrane potential was detected in cells grown on the nanostructure compared to flat substrates. Interestingly, the mitochondrial proteome revealed also the up-regulation of proteins involved in vesicle-mediated transports in combination with a reduction of proteins shared by the endoplasmic reticulum (ER) and mitochondria (CRPX, GRPEL1, HSPD1, DNAJA1, HSPA5, HSPA9, TRAP1), suggesting that the nanostructure alters the protein network involved in the complex interplay between ER and mitochondria in cells grown on the nanostructure. Accordingly, morphological analyses showed a profound reorganization of the mitochondrial-ER connection sites. Conclusions: our results indicate that extracellular nanotopography influences mitochondrial function and morphology, as well as their interplay with other organelles, which is crucial for matching the metabolic needs of the cells. Since mitochondria provide both the energy for cell survival and the signals for efficient glucose-dependent insulin secretion in β-cells, these findings are particularly relevant to successfully engineer scaffolds in order to improve β-cell function and viability in vitro.
mechanotransductuion, insulin, pancreas, diabetes, mitochondria
Settore BIO/09 - Fisiologia
European Association for the Study of Diabetes (EASD)
Article (author)
File in questo prodotto:
File Dimensione Formato  
2020_Article_56thEASDAnnualMeetingOfTheEuro.pdf

accesso riservato

Tipologia: Publisher's version/PDF
Dimensione 50.92 MB
Formato Adobe PDF
50.92 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/2434/789425
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? 0
social impact