Nuclear lipids in chromatin regulation: Biological roles, experimental approaches and existing challenges DOI Creative Commons
Ahmed M. Sayed, Karthik Eswara, Kaian Teles

et al.

Biology of the Cell, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 8, 2024

Abstract Lipids are crucial for various cellular functions. Besides the storage of energy equivalents, these include forming membrane bilayers and serving as signaling molecules. While significant progress has been made in comprehension molecular biology lipids, their functions cell nucleus remain poorly understood. The main role eukaryotic is to provide an environment regulation chromatin which a complex DNA, histones, associated proteins. Recent studies suggest that nuclear lipids play epigenetics. Here, we discuss experimental methods lipid‐chromatin research, including biophysical, structural, approaches, pointing out strengths weaknesses. We take view have far more widespread impact on than currently acknowledged. This gap mostly due existing challenges study biology. Several new, interdisciplinary approaches discussed could aid elucidating roles gene expression.

Language: Английский

Moderate levels of dissolved iron stimulate cellular growth and increase lipid storage in Symbiodinium sp. DOI Creative Commons
Walter Dellisanti, Swathi Murthy, Elena Bollati

et al.

Journal of Phycology, Journal Year: 2025, Volume and Issue: unknown

Published: March 30, 2025

Abstract Dinoflagellates in the family Symbiodiniaceae are fundamental coral reef ecosystems and facilitate essential processes such as photosynthesis, nutrient cycling, calcium carbonate production. Iron (Fe) is an element for physiological of Symbiodiniaceae, yet its role remains poorly understood context cellular development metabolic health. Here, we investigated effect iron availability—0–100 nM Fe(III)—on Symbiodinium sp. ITS2 type A1 cultures quantified content using flow cytometry holotomography. Moderate levels dissolved Fe (50 nM) enhanced growth rates sp., including lipids proteins. We observed distinct patterns, pigment concentrations, morphology under increasing indicating influence availability on physiology. Nondestructive, label‐free holotomographic microscopy enabled single‐cell vivo imaging, revealing higher intracellular lipid accumulation (+57%) response to 50 Fe(III) enrichment. Our findings contribute a deeper understanding relationship between development, with potential implications health resilience face environmental stressors.

Language: Английский

Citations

0
Polarization Gratings Aided Common‐Path Hilbert Holotomography for Label‐Free Lipid Droplets Content Assay DOI
Piotr Zdańkowski, Julianna Winnik, Mikołaj Rogalski

et al.

Laser & Photonics Review, Journal Year: 2025, Volume and Issue: unknown

Published: April 13, 2025

Abstract In this contribution a novel polarization gratings aided common‐path Hilbert holotomography (CP‐HHT) is presented for label‐free 3D refractive index imaging. Addressing limitations in current methods, the extended space‐bandwidth product leveraged through robust phase demodulation using spiral transform. The application of diffraction system enables fully tailored holographic settings such as fringe density and shear, allowing flexible hologram demodulation, while maintaining simplicity robustness. performance tested 3D‐printed (fabricated with two‐photon polymerization) brain phantom fixed HeLa cells supplemented cholesterol oleic acids. Reconstruction analysis indicates that method provides improved spatial resolution to Fourier transform significantly expanded measurement information content. This CP‐HHT approach demonstrates unique (not possible by fluorescence) ability measure lipid droplets enriched acid highlights they exhibit measurable differences their values. These findings suggest sensitive variations neutral content, offering promising insights into droplet heterogeneity supporting its potential sub‐cellular bioimaging applications, thus reinforcing versatility applicability broader applications.

Language: Английский

Citations

0
Holotomographic microscopy reveals label-free quantitative dynamics of endothelial cells during endothelialization DOI Creative Commons
William D. Leineweber,

Gabriela Acevedo Munares,

Christian Leycam

et al.

European Journal of Cell Biology, Journal Year: 2025, Volume and Issue: unknown, P. 151492 - 151492

Published: April 1, 2025

Holotomograhic microscopy (HTM) has emerged as a non-invasive imaging technique that offers high-resolution, quantitative 3D of biological samples. This study explores the application HTM in examining endothelial cells (ECs). overcomes limitations traditional methods capturing real-time dynamics ECs by leveraging refractive index (RI) to map distributions label-free. work demonstrates utility visualizing key cellular processes during endothelialization, wherein anchor, adhere, migrate, and proliferate. Leveraging high resolution power HTM, we show lipid droplets mitochondria are readily visualized, enabling more comprehensive studies on their respective roles endothelialization. The highlights how commercial instrument can uncover novel insights into HUVEC cell behavior, offering potential applications medical diagnostics research, particularly developing treatments for cardiovascular diseases. advanced not only enhances our understanding EC biology but also presents significant step forward diseases, providing robust platform future research therapeutic development.

Language: Английский

Citations

0
The effects of TGF-β-induced activation and starvation of vitamin A and palmitic acid on human stem cell-derived hepatic stellate cells DOI Creative Commons
Ingrid Wilhelmsen, Thomas Combriat, Andrea Dalmao‐Fernández

et al.

Stem Cell Research & Therapy, Journal Year: 2024, Volume and Issue: 15(1)

Published: July 23, 2024

Abstract Background Hepatic stellate cells (HSC) have numerous critical roles in liver function and homeostasis, while they are also known for their importance during injury fibrosis. There is therefore a need relevant vitro human HSC models to fill current knowledge gaps. In particular, the of vitamin A (VA), lipid droplets (LDs), energy metabolism activation poorly understood. Methods this study, pluripotent stem cell-derived HSCs (scHSCs), benchmarked primary HSC, were exposed 48-hour starvation retinol (ROL) palmitic acid (PA) presence or absence potent activator TGF-β. The interventions studied by an extensive set phenotypic functional analyses, including transcriptomic analysis, measurement activation-related proteins cytokines, VA- LD storage, cell metabolism. Results results show that though ROL PA alone did not induce scHSC activation, amplified TGF-β-induced transcriptome. However, lead reduction VA stores. Additionally, reduced glycolysis increased mitochondrial fission observed response Conclusions scHSCs robust studies. loss LDs sufficient vitro, but may amplify response. Collectively, our work provides framework studying healthy diseased conditions.

Language: Английский

Citations

3
Label-free long-term measurements of adipocyte differentiation from patient-driven fibroblasts and quantitative analyses of in situ lipid droplet generation DOI

Eun Young Jeong,

Hye‐Jin Kim, Sumin Lee

et al.

Journal of the Optical Society of America A, Journal Year: 2024, Volume and Issue: 41(11), P. C125 - C125

Published: Oct. 9, 2024

The visualization and tracking of adipocytes their lipid droplets (LDs) during differentiation are pivotal in developmental biology regenerative medicine studies. Traditional staining or labeling methods, however, pose significant challenges due to labor-intensive sample preparation, potential disruption intrinsic cellular physiology, limited observation timeframe. This study introduces a novel method for long-term quantification biophysical parameters LDs unlabeled adipocytes, utilizing the refractive index (RI) distributions cells. We employ low-coherence holotomography (HT) systematically investigate quantitatively analyze 42-day redifferentiation process fat cells into adipocytes. technique yields three-dimensional, high-resolution tomograms enabling precise segmentation based on elevated RI values. Subsequent automated analysis quantifies mean concentration, volume, projected area, dry mass individual LDs, revealing gradual increase corresponding with adipocyte maturation. Our findings demonstrate that HT is potent tool non-invasively monitoring live analyzing LD accumulation. study, therefore, offers valuable insights adipogenesis research, establishing image-based as promising approach these fields.

Language: Английский

Citations

2
Three-dimensional Label-Free Measurements of Adipocyte Differentiation and Lipid Droplet Dynamics DOI Creative Commons

Eun Young Jeong,

Hye‐Jin Kim, Sumin Lee

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 7, 2024

Abstract The visualization and tracking of adipocytes their lipid droplets (LDs) during differentiation are pivotal in developmental biology regenerative medicine studies. Traditional staining or labeling methods, however, pose significant challenges due to labor-intensive sample preparation, potential disruption intrinsic cellular physiology, limited observation timeframe. This study introduces a novel method for long-term quantification biophysical parameters LDs unlabeled adipocytes, utilizing the refractive index (RI) distributions cells. We employ low-coherence holotomography (HT) systematically investigate quantitatively analyze 42-day redifferentiation process fat cells into adipocytes. technique yields three-dimensional, high-resolution tomograms enabling precise segmentation based on elevated RI values. Subsequent automated analysis quantifies mean concentration, volume, projected area, dry mass individual LDs, revealing gradual increase corresponding with adipocyte maturation. Our findings demonstrate that HT is potent tool non-invasively monitoring live analyzing LD accumulation. study, therefore, offers valuable insights adipogenesis research, establishing image-based as promising approach these fields.

Language: Английский

Citations

2
Holotomographic microscopy reveals label-free quantitative dynamics of endothelial cells during endothelialization DOI Open Access
William D. Leineweber,

Gabriela Acevedo Munares,

Christian Leycam

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 6, 2024

Abstract Holotomograhic microscopy (HTM) has emerged as a non-invasive imaging technique that offers high-resolution, quantitative 3D of biological samples. This study explores the application HTM in examining endothelial cells (ECs). overcomes limitations traditional methods capturing real-time dynamics ECs by leveraging refractive index (RI) to map distributions label-free. work demonstrates utility visualizing key cellular processes during endothelialization, wherein anchor, adhere, migrate, and proliferate. Leveraging high resolution power HTM, we show lipid droplets mitochondria are readily visualized, enabling more comprehensive studies on their respective roles endothelialization. The highlights how can uncover novel insights into EC behavior, offering potential applications medical diagnostics research, particularly developing treatments for cardiovascular diseases. advanced not only enhances our understanding biology but also presents significant step forward diseases, providing robust platform future research therapeutic development.

Language: Английский

Citations

2
The scramblases VMP1 and TMEM41B are required for primitive endoderm specification by targeting WNT signaling DOI Creative Commons
Markus Holzner,

Tea Sonicki,

Hugo Hunn

et al.

Cell Death and Differentiation, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 18, 2024

Abstract The ER-resident proteins VMP1 and TMEM41B share a conserved DedA domain, which confers lipid scramblase activity. Loss of either gene results in embryonic lethality mice defects autophagy droplet metabolism. To investigate their role pluripotency lineage specification, we generated Vmp1 Tmem41b mutations mouse stem cells (ESCs). We observed that ESCs carrying show robust self-renewal an unperturbed pluripotent expression profile but accumulate LC3-positive autophagosomes droplets consistent with combined can differentiate into wide range cell types. However, differentiation primitive endoderm-like culture is impaired, the establishment extra-embryonic endoderm (XEN) delayed. Mechanistically, deregulation genes are associated WNT signaling. This further confirmed by surface proteome profiling, identified significant reduction WNT-receptor FZD2 at plasma membrane double mutant ESCs. Importantly, transgenic Fzd2 rescues XEN differentiation. Our findings identify scramblases signaling during development characterize distinct overlapping functions.

Language: Английский

Citations

2
Polarization gratings aided common-path Hilbert holotomography for high-throughput lipid droplets content assay DOI Creative Commons
Piotr Zdańkowski, Julianna Winnik, Mikołaj Rogalski

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: June 17, 2024

Abstract In this contribution we present a novel polarization gratings aided common-path Hilbert holotomography (CP-HHT) for high-throughput 3D refractive index imaging. Addressing limitations in current methods, leverage the extended space-bandwidth product (SBP) through robust phase demodulation using spiral transform. Thanks to application of diffraction our system enables fully tailored holographic settings such as fringe density and shear, thus allowing flexible hologram demodulation, while maintaining simplicity robustness. The performance is tested on 3D-printed (using two-photon polymerization) brain phantom fixed HeLa cells supplemented with cholesterol oleic acids. Reconstruction analysis indicates that method provides comparable results resolution Fourier transform significantly expanded measurement throughput. Our CP-HHT approach demonstrates unique (not possible by fluorescence) (especially when compared cryogenic electron microscopy) capability differentiate between esters vs. triacylglycerol (TAG) rich lipid droplets (LDs), has potential label-free biological research at sub-cellular level. quantitative LDs’ emphasizes method’s sensitivity distinguishing LDs different neutral content, offering new insights into LD heterogeneity, reinforcing versatility applicability broader bioimaging applications.

Language: Английский

Citations

0
Moderate levels of dissolved iron stimulate cellular growth and increase lipid storage in Symbiodinium sp. DOI
Walter Dellisanti, Swathi Murthy, Elena Bollati

et al.

Research Square (Research Square), Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 30, 2024

Abstract Dinoflagellates in the family Symbiodiniaceae are fundamental coral reef ecosystems and facilitate essential processes such as photosynthesis, nutrient cycling, calcium carbonate production. Iron (Fe) is an element for physiological of Symbiodiniaceae, yet its role remains poorly understood context cellular development metabolic health. Here, we investigated effect iron availability (0 to 100 nM Fe(III)) on Symbiodiniumsp. ITS2 type A1 cultures quantified content using flow cytometry holotomography. Moderate levels dissolved Fe (50 nM) enhanced growth rates Symbiodinium sp., including lipids proteins. We observed distinct patterns, pigment concentrations, morphology under increasing indicating influence physiology. Non-destructive, label-free holotomographic microscopy enabled single cell in vivo revealing higher intracellular lipid accumulation (+57%) response 50 Fe(III) enrichment. Our findings contribute a deeper understanding relationship between development, with potential implications health resilience face environmental stressors.

Language: Английский

Citations

0