1
|
Rensonnet A, Tipping WJ, Malherbe C, Faulds K, Eppe G, Graham D. Spectral fingerprinting of cellular lipid droplets using stimulated Raman scattering microscopy and chemometric analysis. Analyst 2024; 149:553-562. [PMID: 38088863 DOI: 10.1039/d3an01684f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
Hyperspectral stimulated Raman scattering (SRS) microscopy is a powerful method for direct visualisation and compositional analysis of cellular lipid droplets. Here we report the application of spectral phasor analysis as a convenient method for the segmentation of lipid droplets using the hyperspectral SRS spectrum in the high wavenumber and fingerprint region of the spectrum. Spectral phasor analysis was shown to discriminate six fatty acids based on vibrational spectroscopic features in solution. The methodology was then applied to studying fatty acid metabolism and storage in a mammalian cancer cell model and during drug-induced steatosis in a hepatocellular carcinoma cell model. The accumulation of fatty acids into cellular lipid droplets was shown to vary as a function of the degree of unsaturation, whilst in a model of drug-induced steatosis, the detection of increased saturated fatty acid esters was observed. Taking advantage of the fingerprint and high wavenumber regions of the SRS spectrum has yielded a greater insight into lipid droplet composition in a cellular context. This approach will find application in the label-free profiling of intracellular lipids in complex disease models.
Collapse
Affiliation(s)
- Aurélie Rensonnet
- Centre for Molecular Nanometrology, WestCHEM, Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow, G1 1RD, UK.
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège, Allée du 6 Août, 4000 Liège, Belgium
| | - William J Tipping
- Centre for Molecular Nanometrology, WestCHEM, Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow, G1 1RD, UK.
| | - Cedric Malherbe
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège, Allée du 6 Août, 4000 Liège, Belgium
| | - Karen Faulds
- Centre for Molecular Nanometrology, WestCHEM, Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow, G1 1RD, UK.
| | - Gauthier Eppe
- Mass Spectrometry Laboratory, MolSys Research Unit, University of Liège, Allée du 6 Août, 4000 Liège, Belgium
| | - Duncan Graham
- Centre for Molecular Nanometrology, WestCHEM, Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow, G1 1RD, UK.
| |
Collapse
|
2
|
Zhang H, Fang J, Dai Y, Pan Y, Chu K, Smith ZJ. Rapid Intracellular Detection and Analysis of Lipid Droplets' Morpho-Chemical Composition by Phase-Guided Raman Sampling. Anal Chem 2023; 95:13555-13565. [PMID: 37650651 DOI: 10.1021/acs.analchem.3c02181] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Intracellular lipid droplets (LDs) are dynamic, complex organelles involved in nearly all aspects of cellular metabolism. In situ characterization methods are primarily limited to fluorescence imaging, which yields limited chemical information, or Raman spectroscopy, which provides excellent chemical profiling but very low throughput. Here, we propose a new paradigm where locations of both large and small droplets are obtained automatically from high-resolution phase images and fed into a galvomirror-controlled Raman sampling arm to obtain the full spectrum of each LD efficiently. Using this phase-guided Raman sampling, we can characterize hundreds of LDs within a single cell in minutes and easily acquire more than 40,000 high-quality spectra. The data set revealed strong, cell line-dependent, cell-dependent, and individual droplet-dependent composition changes to various culture conditions. In particular, we revealed a strong competitive relationship between mono- and polyunsaturated fatty acids, where supplementation with one led to a relative decrease in the other.
Collapse
Affiliation(s)
- Hao Zhang
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jingde Fang
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yichuan Dai
- Department of Advanced Manufacturing, Nanchang University, Nanchang, Jiangxi 330027, China
| | - Yang Pan
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Kaiqin Chu
- University of Science and Technology of China, Suzhou Institute for Advanced Research, Suzhou, Jiangsu 215123, China
| | - Zachary J Smith
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, Anhui 230026, China
| |
Collapse
|
3
|
Spratt SJ, Mizuguchi T, Akaboshi H, Kosakamoto H, Okada R, Obata F, Ozeki Y. Imaging the uptake of deuterated methionine in Drosophila with stimulated Raman scattering. Front Chem 2023; 11:1141920. [PMID: 37065821 PMCID: PMC10090404 DOI: 10.3389/fchem.2023.1141920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 03/16/2023] [Indexed: 03/31/2023] Open
Abstract
Introduction: Visualizing small individual biomolecules at subcellular resolution in live cells and tissues can provide valuable insights into metabolic activity in heterogeneous cells, but is challenging.Methods: Here, we used stimulated Raman scattering (SRS) microscopy to image deuterated methionine (d-Met) incorporated into Drosophila tissues in vivo.Results: Our results demonstrate that SRS can detect a range of previously uncharacterized cell-to-cell differences in d-Met distribution within a tissue at the subcellular level.Discussion: These results demonstrate the potential of SRS microscopy for metabolic imaging of less abundant but important amino acids such as methionine in tissue.
Collapse
Affiliation(s)
- Spencer J. Spratt
- Department of Electrical Engineering and Information Systems, The University of Tokyo, Tokyo, Japan
| | - Takaha Mizuguchi
- Department of Electrical Engineering and Information Systems, The University of Tokyo, Tokyo, Japan
| | - Hikaru Akaboshi
- Department of Electrical Engineering and Information Systems, The University of Tokyo, Tokyo, Japan
| | - Hina Kosakamoto
- Laboratory for Nutritional Biology, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Rina Okada
- Laboratory for Nutritional Biology, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Fumiaki Obata
- Laboratory for Nutritional Biology, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
- Laboratory of Molecular Cell Biology and Development, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Yasuyuki Ozeki
- Department of Electrical Engineering and Information Systems, The University of Tokyo, Tokyo, Japan
- *Correspondence: Yasuyuki Ozeki,
| |
Collapse
|
4
|
Jia H, Yue S. Stimulated Raman Scattering Imaging Sheds New Light on Lipid Droplet Biology. J Phys Chem B 2023; 127:2381-2394. [PMID: 36897936 PMCID: PMC10042165 DOI: 10.1021/acs.jpcb.3c00038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/05/2023] [Indexed: 03/11/2023]
Abstract
A lipid droplet (LD) is a dynamic organelle closely associated with cellular functions and energy homeostasis. Dysregulated LD biology underlies an increasing number of human diseases, including metabolic disease, cancer, and neurodegenerative disorder. Commonly used lipid staining and analytical tools have difficulty providing the information regarding LD distribution and composition at the same time. To address this problem, stimulated Raman scattering (SRS) microscopy uses the intrinsic chemical contrast of biomolecules to achieve both direct visualization of LD dynamics and quantitative analysis of LD composition with high molecular selectivity at the subcellular level. Recent developments of Raman tags have further enhanced sensitivity and specificity of SRS imaging without perturbing molecular activity. With these advantages, SRS microscopy has offered great promise for deciphering LD metabolism in single live cells. This article overviews and discusses the latest applications of SRS microscopy as an emerging platform to dissect LD biology in health and disease.
Collapse
Affiliation(s)
- Hao Jia
- Key Laboratory of Biomechanics and
Mechanobiology (Beihang University), Ministry of Education, Institute
of Medical Photonics, Beijing Advanced Innovation Center for Biomedical
Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Shuhua Yue
- Key Laboratory of Biomechanics and
Mechanobiology (Beihang University), Ministry of Education, Institute
of Medical Photonics, Beijing Advanced Innovation Center for Biomedical
Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| |
Collapse
|
5
|
Jang H, Li Y, Fung AA, Bagheri P, Hoang K, Skowronska-Krawczyk D, Chen X, Wu JY, Bintu B, Shi L. Super-resolution SRS microscopy with A-PoD. Nat Methods 2023; 20:448-458. [PMID: 36797410 PMCID: PMC10246886 DOI: 10.1038/s41592-023-01779-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 01/17/2023] [Indexed: 02/18/2023]
Abstract
Stimulated Raman scattering (SRS) offers the ability to image metabolic dynamics with high signal-to-noise ratio. However, its spatial resolution is limited by the numerical aperture of the imaging objective and the scattering cross-section of molecules. To achieve super-resolved SRS imaging, we developed a deconvolution algorithm, adaptive moment estimation (Adam) optimization-based pointillism deconvolution (A-PoD) and demonstrated a spatial resolution of lower than 59 nm on the membrane of a single lipid droplet (LD). We applied A-PoD to spatially correlated multiphoton fluorescence imaging and deuterium oxide (D2O)-probed SRS (DO-SRS) imaging from diverse samples to compare nanoscopic distributions of proteins and lipids in cells and subcellular organelles. We successfully differentiated newly synthesized lipids in LDs using A-PoD-coupled DO-SRS. The A-PoD-enhanced DO-SRS imaging method was also applied to reveal metabolic changes in brain samples from Drosophila on different diets. This new approach allows us to quantitatively measure the nanoscopic colocalization of biomolecules and metabolic dynamics in organelles.
Collapse
Affiliation(s)
- Hongje Jang
- Shu Chien - Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Yajuan Li
- Shu Chien - Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Anthony A Fung
- Shu Chien - Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Pegah Bagheri
- Shu Chien - Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Khang Hoang
- Shu Chien - Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | | | - Xiaoping Chen
- The Ken and Ruth Davee Department of Neurology, Northwestern University, Chicago, IL, USA
| | - Jane Y Wu
- The Ken and Ruth Davee Department of Neurology, Northwestern University, Chicago, IL, USA
| | - Bogdan Bintu
- Shu Chien - Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Lingyan Shi
- Shu Chien - Gene Lay Department of Bioengineering, University of California San Diego, La Jolla, CA, USA.
| |
Collapse
|
6
|
Hislop EW, Tipping WJ, Faulds K, Graham D. Label-Free Imaging of Lipid Droplets in Prostate Cells Using Stimulated Raman Scattering Microscopy and Multivariate Analysis. Anal Chem 2022; 94:8899-8908. [PMID: 35699644 PMCID: PMC9244870 DOI: 10.1021/acs.analchem.2c00236] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Hyperspectral stimulated
Raman scattering (SRS) microscopy is a
powerful imaging modality for the analysis of biological systems.
Here, we report the application of k-means cluster
analysis (KMCA) of multi-wavelength SRS images in the high-wavenumber
region of the Raman spectrum as a robust and reliable method for the
segmentation of cellular organelles based on the intrinsic SRS spectrum.
KMCA has been applied to the study of the endogenous lipid biochemistry
of prostate cancer and prostate healthy cell models, while the corresponding
SRS spectrum of the lipid droplet (LD) cluster enabled direct comparison
of their composition. The application of KMCA in visualizing the LD
content of prostate cell models following the inhibition of de novo
lipid synthesis (DNL) using the acetyl-coA carboxylase inhibitor,
5-(tetradecyloxy)-2-furoic acid (TOFA), is demonstrated. This method
identified a reliance of prostate cancer cell models upon DNL for
metabolic requirements, with a significant reduction in the cellular
LD content after treatment with TOFA, which was not observed in normal
prostate cell models. SRS imaging combined with KMCA is a robust method
for investigating drug–cell interactions in a label-free manner.
Collapse
Affiliation(s)
- Ewan W Hislop
- Centre for Molecular Nanometrology, WestCHEM, Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow G1 1RD, U.K
| | - William J Tipping
- Centre for Molecular Nanometrology, WestCHEM, Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow G1 1RD, U.K
| | - Karen Faulds
- Centre for Molecular Nanometrology, WestCHEM, Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow G1 1RD, U.K
| | - Duncan Graham
- Centre for Molecular Nanometrology, WestCHEM, Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, Glasgow G1 1RD, U.K
| |
Collapse
|
7
|
Li Y, Bagheri P, Chang P, Zeng A, Hao J, Fung A, Wu JY, Shi L. Direct Imaging of Lipid Metabolic Changes in Drosophila Ovary During Aging Using DO-SRS Microscopy. FRONTIERS IN AGING 2022; 2:819903. [PMID: 35822015 PMCID: PMC9261447 DOI: 10.3389/fragi.2021.819903] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 12/29/2021] [Indexed: 01/09/2023]
Abstract
Emerging studies have shown that lipids and proteins play versatile roles in various aspects of aging. High-resolution in situ optical imaging provides a powerful approach to study the metabolic dynamics of lipids and proteins during aging. Here, we integrated D2O probing and stimulated Raman scattering (DO-SRS) microscopy to directly visualize metabolic changes in aging Drosophila ovary. The subcellular spatial distribution of de novo protein synthesis and lipogenesis in ovary was quantitatively imaged and examined. Our Raman spectra showed that early stages follicles were protein-enriched whereas mature eggs were lipid-enriched. DO-SRS imaging showed a higher protein synthesis in the earlier developing stages and an increased lipid turned over at the late stage. Aged (35 days) flies exhibited a dramatic decrease in metabolic turnover activities of both proteins and lipids, particularly, in the germ stem cell niche of germarium. We found an accumulation of unsaturated lipids in the nurse cells and oocytes in old flies, suggesting that unsaturated lipids may play an important role in the processes of oocyte maturation. We further detected changes in mitochondrial morphology and accumulation of Cytochrome c during aging. To our knowledge, this is the first study that directly visualizes spatiotemporal changes in lipid and protein metabolism in Drosophila ovary during development and aging processes. Our study not only demonstrates the application of a new imaging platform in visualizing metabolic dynamics of lipids and proteins in situ but also unravels how the metabolic activity and lipid distribution change in Drosophila ovary during aging.
Collapse
Affiliation(s)
- Yajuan Li
- The Department of Bioengineering, University of California San Diego, La Jolla, CA, United States
| | - Pegah Bagheri
- The Department of Bioengineering, University of California San Diego, La Jolla, CA, United States
| | - Phyllis Chang
- The Department of Bioengineering, University of California San Diego, La Jolla, CA, United States
| | - Audrey Zeng
- The Department of Bioengineering, University of California San Diego, La Jolla, CA, United States
| | - Jie Hao
- The Department of Bioengineering, University of California San Diego, La Jolla, CA, United States
| | - Anthony Fung
- The Department of Bioengineering, University of California San Diego, La Jolla, CA, United States
| | - Jane Y. Wu
- Department of Neurology, Northwestern University, Chicago, IL, United States
| | - Lingyan Shi
- The Department of Bioengineering, University of California San Diego, La Jolla, CA, United States
- *Correspondence: Lingyan Shi,
| |
Collapse
|