Cell lipid droplet heterogeneity and altered biophysical properties induced by cell stress and metabolic imbalance

0573306 - ÚFCH JH 2024 RIV NL eng J - Článek v odborném periodiku
Ventura, A. E. - Pokorná, Šárka - Huhn, N. - Santos, T. C. B. - Prieto, M. - Futerman, A. H. - Silva, L. C.
Cell lipid droplet heterogeneity and altered biophysical properties induced by cell stress and metabolic imbalance.
Biochimica Et Biophysica Acta-Molecular and Cell Biology of Lipids. Roč. 1868, č. 9 (2023), č. článku 159347. ISSN 1388-1981. E-ISSN 1879-2618
Institucionální podpora: RVO:61388955
Klíčová slova: Cancer * Fluorescence microscopy * Laurdan generalized polarization * Lipid droplet diversity * Lipid droplet hydrophobicity * Live cell imaging
Obor OECD: Physical chemistry
Impakt faktor: 4.8, rok: 2022
Způsob publikování: Open access

Lipid droplets (LD) are important regulators of lipid metabolism and are implicated in several diseases. However, the mechanisms underlying the roles of LD in cell pathophysiology remain elusive. Hence, new approaches that enable better characterization of LD are essential. This study establishes that Laurdan, a widely used fluorescent probe, can be used to label, quantify, and characterize changes in cell LD properties. Using lipid mixtures containing artificial LD we show that Laurdan GP depends on LD composition. Accordingly, enrichment in cholesterol esters (CE) shifts Laurdan GP from ∼0.60 to ∼0.70. Moreover, live-cell confocal microscopy shows that cells present multiple LD populations with distinctive biophysical features. The hydrophobicity and fraction of each LD population are cell type dependent and change differently in response to nutrient imbalance, cell density, and upon inhibition of LD biogenesis. The results show that cellular stress caused by increased cell density and nutrient overload increased the number of LD and their hydrophobicity and contributed to the formation of LD with very high GP values, likely enriched in CE. In contrast, nutrient deprivation was accompanied by decreased LD hydrophobicity and alterations in cell plasma membrane properties. In addition, we show that cancer cells present highly hydrophobic LD, compatible with a CE enrichment of these organelles. The distinct biophysical properties of LD contribute to the diversity of these organelles, suggesting that the specific alterations in their properties might be one of the mechanisms triggering LD pathophysiological actions and/or be related to the different mechanisms underlying LD metabolism.
Trvalý link: https://hdl.handle.net/11104/0343772