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Song A, Zhao N, Hilpert DC, Perry C, Baur JA, Wallace DC, Schaefer PM. Visualizing subcellular changes in the NAD(H) pool size versus redox state using fluorescence lifetime imaging microscopy of NADH. Commun Biol 2024; 7:428. [PMID: 38594590 PMCID: PMC11004000 DOI: 10.1038/s42003-024-06123-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 03/29/2024] [Indexed: 04/11/2024] Open
Abstract
NADH autofluorescence imaging is a promising approach for visualizing energy metabolism at the single-cell level. However, it is sensitive to the redox ratio and the total NAD(H) amount, which can change independently from each other, for example with aging. Here, we evaluate the potential of fluorescence lifetime imaging microscopy (FLIM) of NADH to differentiate between these modalities.We perform targeted modifications of the NAD(H) pool size and ratio in cells and mice and assess the impact on NADH FLIM. We show that NADH FLIM is sensitive to NAD(H) pool size, mimicking the effect of redox alterations. However, individual components of the fluorescence lifetime are differently impacted by redox versus pool size changes, allowing us to distinguish both modalities using only FLIM. Our results emphasize NADH FLIM's potential for evaluating cellular metabolism and relative NAD(H) levels with high spatial resolution, providing a crucial tool for our understanding of aging and metabolism.
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Affiliation(s)
- Angela Song
- Center for Mitochondrial and Epigenomic Medicine, Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Nicole Zhao
- Center for Mitochondrial and Epigenomic Medicine, Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Diana C Hilpert
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA
| | - Caroline Perry
- Department of Physiology and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Joseph A Baur
- Department of Physiology and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Douglas C Wallace
- Center for Mitochondrial and Epigenomic Medicine, Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA.
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Patrick M Schaefer
- Center for Mitochondrial and Epigenomic Medicine, Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, USA.
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2
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Keck CM, Abdelkader A, Pelikh O, Wiemann S, Kaushik V, Specht D, Eckert RW, Alnemari RM, Dietrich H, Brüßler J. Assessing the Dermal Penetration Efficacy of Chemical Compounds with the Ex-Vivo Porcine Ear Model. Pharmaceutics 2022; 14:pharmaceutics14030678. [PMID: 35336052 PMCID: PMC8951478 DOI: 10.3390/pharmaceutics14030678] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/08/2022] [Accepted: 03/15/2022] [Indexed: 11/16/2022] Open
Abstract
(1) Background: The ex vivo porcine ear model is often used for the determination of the dermal penetration efficacy of chemical compounds. This study investigated the influence of the post-slaughter storage time of porcine ears on the dermal penetration efficacy of chemical compounds. (2) Methods: Six different formulations (curcumin and different fluorescent dyes in different vehicles and/or nanocarriers) were tested on ears that were (i) freshly obtained, (ii) stored for 24 or 48 h at 4 °C after slaughter before use and (iii) freshly frozen and defrosted 12 h before use. (3) Results: Results showed that porcine ears undergo post-mortem changes. The changes can be linked to rigor mortis and all other well-described phenomena that occur with carcasses after slaughter. The post-mortem changes modify the skin properties of the ears and affect the penetration efficacy. The onset of rigor mortis causes a decrease in the water-holding capacity of the ears, which leads to reduced penetration of chemical compounds. The water-holding capacity increases once the rigor is released and results in an increased penetration efficacy for chemical compounds. Despite different absolute penetration values, no differences in the ranking of penetration efficacies between the different formulations were observed between the differently aged ears. (4) Conclusions: All different types of ears can be regarded to be suitable for dermal penetration testing of chemical compounds. The transepidermal water loss (TEWL) and/or skin hydration of the ears were not correlated with the ex vivo penetration efficacy because both an impaired skin barrier and rigor mortis cause elevated skin hydration and TEWL values but an opposite penetration efficacy. Other additional values (for example, pH and/or autofluorescence of the skin) should, therefore, be used to select suitable and non-suitable skin areas for ex vivo penetration testing. Finally, data from this study confirmed that smartFilms and nanostructured lipid carriers (NLC) represent superior formulation strategies for efficient dermal and transdermal delivery of curcumin.
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3
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Hopf NB, Champmartin C, Schenk L, Berthet A, Chedik L, Du Plessis JL, Franken A, Frasch F, Gaskin S, Johanson G, Julander A, Kasting G, Kilo S, Larese Filon F, Marquet F, Midander K, Reale E, Bunge AL. Reflections on the OECD guidelines for in vitro skin absorption studies. Regul Toxicol Pharmacol 2020; 117:104752. [PMID: 32791089 DOI: 10.1016/j.yrtph.2020.104752] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/20/2020] [Accepted: 07/27/2020] [Indexed: 02/07/2023]
Abstract
At the 8th conference of Occupational and Environmental Exposure of the Skin to Chemicals (OEESC) (16-18 September 2019) in Dublin, Ireland, several researchers performing skin permeation assays convened to discuss in vitro skin permeability experiments. We, along with other colleagues, all of us hands-on skin permeation researchers, present here the results from our discussions on the available OECD guidelines. The discussions were especially focused on three OECD skin absorption documents, including a recent revision of one: i) OECD Guidance Document 28 (GD28) for the conduct of skin absorption studies (OECD, 2004), ii) Test Guideline 428 (TGD428) for measuring skin absorption of chemical in vitro (OECD, 2004), and iii) OECD Guidance Notes 156 (GN156) on dermal absorption issued in 2011 (OECD, 2011). GN156 (OECD, 2019) is currently under review but not finalized. A mutual concern was that these guidance documents do not comprehensively address methodological issues or the performance of the test, which might be partially due to the years needed to finalize and update OECD documents with new skin research evidence. Here, we summarize the numerous factors that can influence skin permeation and its measurement, and where guidance on several of these are omitted and often not discussed in published articles. We propose several improvements of these guidelines, which would contribute in harmonizing future in vitro skin permeation experiments.
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Affiliation(s)
- N B Hopf
- Centre for Primary Care and Public Health (Unisante), Department for Occupational and Environmental Health (DSTE), Exposure Science Unit, Switzerland.
| | - C Champmartin
- French National Research and Safety Institute for the Prevention of Occupational Accidents and Diseases (INRS), France.
| | - L Schenk
- Karolinska Institutet, Institute of Environmental Medicine, Unit of Integrative Toxicology, Sweden.
| | - A Berthet
- Centre for Primary Care and Public Health (Unisante), Department for Occupational and Environmental Health (DSTE), Exposure Science Unit, Switzerland.
| | - L Chedik
- French National Research and Safety Institute for the Prevention of Occupational Accidents and Diseases (INRS), France.
| | - J L Du Plessis
- Occupational Hygiene and Health Research Initiative (OHHRI) North-West University, South Africa.
| | - A Franken
- Occupational Hygiene and Health Research Initiative (OHHRI) North-West University, South Africa.
| | - F Frasch
- Occupational Hygiene and Health Research Initiative (OHHRI) North-West University, South Africa.
| | - S Gaskin
- University of Adelaide, School of Public Health, Health and Medical Sciences, Australia.
| | - G Johanson
- Karolinska Institutet, Institute of Environmental Medicine, Unit of Integrative Toxicology, Sweden.
| | - A Julander
- Karolinska Institutet, Institute of Environmental Medicine, Unit of Integrative Toxicology, Sweden.
| | - G Kasting
- University of Cincinnati, James L. Winkle College of Pharmacy, USA.
| | - S Kilo
- Friedrich-Alexander University Erlangen-Nürnberg, Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Germany.
| | - F Larese Filon
- University of Trieste, Clinical Unit of Occupational Medicine, Department of Medical, Surgical and Health Sciences, Italy.
| | - F Marquet
- French National Research and Safety Institute for the Prevention of Occupational Accidents and Diseases (INRS), France.
| | - K Midander
- Karolinska Institutet, Institute of Environmental Medicine, Unit of Integrative Toxicology, Sweden.
| | - E Reale
- Centre for Primary Care and Public Health (Unisante), Department for Occupational and Environmental Health (DSTE), Exposure Science Unit, Switzerland.
| | - A L Bunge
- Colorado School of Mines, Chemical and Biological Engineering, USA.
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4
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Rodimova S, Kuznetsova D, Bobrov N, Elagin V, Shcheslavskiy V, Zagainov V, Zagaynova E. Mapping metabolism of liver tissue using two-photon FLIM. BIOMEDICAL OPTICS EXPRESS 2020; 11:4458-4470. [PMID: 32923056 PMCID: PMC7449714 DOI: 10.1364/boe.398020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/28/2020] [Accepted: 06/30/2020] [Indexed: 05/08/2023]
Abstract
Although fluorescence lifetime imaging microscopy (FLIM) has been extensively applied to study cellular metabolism in the liver, there is neither an established approach to analyze the data, nor have appropriate protocols been developed to maintain the optical metabolic characteristics in the ex vivo liver tissue sample. Here, we show that a tri-exponential decay fitting model for the fluorescence signal from nicotinamide adenine dinucleotide (NAD(P)H) and the use of ex vivo samples allows the most appropriate processing of the FLIM data. Moreover, we determine the medium that maintains the initial metabolic state of hepatocytes (liver cells), most effectively. Our results should be particularly relevant for the interrogation of liver samples, not only in laboratory research, but also in clinical settings in the future.
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Affiliation(s)
- Svetlana Rodimova
- Privolzhsky Research Medical University, Institute of Experimental Oncology and Biomedical Technologies, 10/1 Minin and Pozharsky sq., Nizhny Novgorod 603950, Russia
- N.I. Lobachevsky Nizhny Novgorod National Research State University, Nizhny Novgorod 603950, Russia
| | - Daria Kuznetsova
- Privolzhsky Research Medical University, Institute of Experimental Oncology and Biomedical Technologies, 10/1 Minin and Pozharsky sq., Nizhny Novgorod 603950, Russia
| | - Nikolai Bobrov
- Privolzhsky Research Medical University, Institute of Experimental Oncology and Biomedical Technologies, 10/1 Minin and Pozharsky sq., Nizhny Novgorod 603950, Russia
- The Volga District Medical Centre of Federal Medical and Biological Agency, 14 Ilinskaya, Nizhny Novgorod 603000, Russia
| | - Vadim Elagin
- Privolzhsky Research Medical University, Institute of Experimental Oncology and Biomedical Technologies, 10/1 Minin and Pozharsky sq., Nizhny Novgorod 603950, Russia
| | - Vladislav Shcheslavskiy
- Privolzhsky Research Medical University, Institute of Experimental Oncology and Biomedical Technologies, 10/1 Minin and Pozharsky sq., Nizhny Novgorod 603950, Russia
- Becker&Hickl GmbH, Nunsdorfer Ring 7-9, Berlin 12277, Germany
| | - Vladimir Zagainov
- Privolzhsky Research Medical University, Institute of Experimental Oncology and Biomedical Technologies, 10/1 Minin and Pozharsky sq., Nizhny Novgorod 603950, Russia
- The Volga District Medical Centre of Federal Medical and Biological Agency, 14 Ilinskaya, Nizhny Novgorod 603000, Russia
| | - Elena Zagaynova
- Privolzhsky Research Medical University, Institute of Experimental Oncology and Biomedical Technologies, 10/1 Minin and Pozharsky sq., Nizhny Novgorod 603950, Russia
- N.I. Lobachevsky Nizhny Novgorod National Research State University, Nizhny Novgorod 603950, Russia
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5
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Pouli D, Thieu HT, Genega EM, Baecher-Lind L, House M, Bond B, Roncari DM, Evans ML, Rius-Diaz F, Munger K, Georgakoudi I. Label-free, High-Resolution Optical Metabolic Imaging of Human Cervical Precancers Reveals Potential for Intraepithelial Neoplasia Diagnosis. CELL REPORTS MEDICINE 2020; 1. [PMID: 32577625 PMCID: PMC7311071 DOI: 10.1016/j.xcrm.2020.100017] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
While metabolic changes are considered a cancer hallmark, their assessment has not been incorporated in the detection of early or precancers, when treatment is most effective. Here, we demonstrate that metabolic changes are detected in freshly excised human cervical precancerous tissues using label-free, non-destructive imaging of the entire epithelium. The images rely on two-photon excited fluorescence from two metabolic co-enzymes, NAD(P)H and FAD, and have micron-level resolution, enabling sensitive assessments of the redox ratio and mitochondrial fragmentation, which yield metrics of metabolic function and heterogeneity. Simultaneous characterization of morphological features, such as the depth-dependent variation of the nuclear:cytoplasmic ratio, is demonstrated. Multi-parametric analysis combining several metabolic metrics with morphological ones enhances significantly the diagnostic accuracy of identifying high-grade squamous intraepithelial lesions. Our results motivate the translation of such functional metabolic imaging to in vivo studies, which may enable improved identification of cervical lesions, and other precancers, at the bedside.
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Affiliation(s)
- Dimitra Pouli
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA.,Present address: Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Avenue, Boston, MA 02115, USA
| | - Hong-Thao Thieu
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Elizabeth M Genega
- Department of Pathology and Laboratory Medicine, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Laura Baecher-Lind
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Michael House
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Brian Bond
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA.,Present address: Department of Obstetrics and Gynecology, University of Massachusetts School of Medicine, 55 Lake Avenue North, Worcester, MA 01655, USA
| | - Danielle M Roncari
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Megan L Evans
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Francisca Rius-Diaz
- Department of Preventive Medicine and Public Health, Faculty of Medicine, University of Málaga, 32 Louis Pasteur Boulevard, 29071 Málaga, Spain
| | - Karl Munger
- Department of Developmental, Molecular, and Chemical Biology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Irene Georgakoudi
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA.,Lead Contact
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6
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Romano RA, Teixeira Rosa RG, Salvio AG, Jo JA, Kurachi C. Multispectral autofluorescence dermoscope for skin lesion assessment. Photodiagnosis Photodyn Ther 2020; 30:101704. [PMID: 32135314 DOI: 10.1016/j.pdpdt.2020.101704] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 02/07/2020] [Accepted: 02/28/2020] [Indexed: 01/21/2023]
Abstract
Basal cell carcinoma (BCC) is the most common type of skin cancer. Diagnosis and edge assessment of BCC lesions are based on clinical and dermoscopy evaluation, which are strongly dependent on the expertise and training of the physician. There is a high rate of underdiagnosis because BCC is frequently confused with certain common benign lesions and is often indistinguishable from the surrounding healthy tissue. In the present study, a multispectral fluorescence lifetime imaging (FLIm) dermoscopy system, designed for imaging and analyzing the autofluorescence emission of skin tissue, was used to image thirty-eight patients with diagnosed nodular BCC (nBCC) lesions, using clinically acceptable levels of excitation light exposure. With this system, skin autofluorescence was imaged simultaneously using three emission bands: 390 ± 20 nm, 452 ± 22 nm, and >496 nm, preferentially targeting collagen, NADH, and FAD autofluorescence, respectively. Statistical classifiers based on FLIm features developed to discriminate BCC from healthy tissue showed promising performance (ROC area-under-the-curve of 0.82). This study demonstrates the feasibility of clinically performing multispectral endogenous FLIm dermoscopy providing baseline results indicating the potential of this technology as an image-guided tool to improve the delineation of nBCC during surgical lesion resection.
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Affiliation(s)
- Renan Arnon Romano
- São Carlos Institute of Physics, University of São Paulo, P.O. Box 369, 13560-970, São Carlos, SP, Brazil.
| | | | | | - Javier A Jo
- School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK, USA
| | - Cristina Kurachi
- São Carlos Institute of Physics, University of São Paulo, P.O. Box 369, 13560-970, São Carlos, SP, Brazil
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7
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Holmes AM, Mackenzie L, Roberts MS. Disposition and measured toxicity of zinc oxide nanoparticles and zinc ions against keratinocytes in cell culture and viable human epidermis. Nanotoxicology 2020; 14:263-274. [PMID: 32003270 DOI: 10.1080/17435390.2019.1692382] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Suspensions of the UV filter, zinc oxide nanoparticles (ZnO NP), are widely used in sunscreen products. This paper compared the relative disposition and local cytotoxicity of ZnO NP, and zinc ions formed on its dissolution, against keratinocyte cultures and in the human epidermis (ex vivo) after application of suspensions of ZnO NP. HaCaT keratinocyte cytotoxicities were found to be related to labile intra-cellular zinc but also total zinc and extra-cellular concentrations in cell culture media and to a degree ameliorated by the presence of a zinc chelating agent. Secondly, the zinc species were then dosed onto exposed ex vivo viable human epidermis and it was found that an increase in labile zinc level correlated with a shift in the metabolic state of the viable epidermis. This study highlights that excised viable skin acts as a more relevant model for determining cutaneous toxicity over keratinocyte monolayers in vitro.
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Affiliation(s)
- Amy M Holmes
- School of Pharmacy and Medical Sciences, The University of South Australia, Adelaide, Australia.,Quality Medication Care Pty Ltd, Basil Hetzel Institute for Translational Medical Research, The Queen Elizabeth Hospital, Adelaide, Australia
| | - Lorraine Mackenzie
- School of Pharmacy and Medical Sciences, The University of South Australia, Adelaide, Australia.,Quality Medication Care Pty Ltd, Basil Hetzel Institute for Translational Medical Research, The Queen Elizabeth Hospital, Adelaide, Australia
| | - Michael S Roberts
- School of Pharmacy and Medical Sciences, The University of South Australia, Adelaide, Australia.,Therapeutics Research Centre, The University of Queensland, Brisbane, Australia
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8
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Mohammed YH, Barkauskas DS, Holmes A, Grice J, Roberts MS. Noninvasive in vivo human multiphoton microscopy: a key method in proving nanoparticulate zinc oxide sunscreen safety. JOURNAL OF BIOMEDICAL OPTICS 2020; 25:1-19. [PMID: 31939224 PMCID: PMC7008509 DOI: 10.1117/1.jbo.25.1.014509] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 12/03/2019] [Indexed: 05/27/2023]
Abstract
We describe the contribution of our in vivo multiphoton microscopy (MPM) studies over the last ten years with DermaInspect;® (JenLab, Germany), a CE-certified medical tomograph based on detection of fluorescent biomolecules, to the assessment of possible penetration of nanoparticulate zinc oxide in sunscreen through human skin. At the time we started our work, there was a strong movement for the precautionary principle to be applied to the use of nanoparticles in consumer products due to a lack of knowledge. The combined application of different MPM modalities, including spectral imaging, fluorescence lifetime imaging, second harmonic fluorescence generation, and phosphorescence microscopy, has provided overwhelming evidence that nanoparticle zinc oxide particles do not penetrate human skin when applied to various skin types with a range of methods of topical sunscreen application. MPM has also been used to study the viable epidermal morphology and redox state in supporting the safe use of topical zinc oxide nanoparticles. The impact of this work is emphasized by the recent proposed rule by the United States FDA on Sunscreen Drug Products for Over-the-Counter Human Use, which listed only zinc oxide and titanium dioxide of the currently marketed products to be generally recognized as safe and effective.
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Affiliation(s)
- Yousuf H. Mohammed
- University of Queensland, University of Queensland Diamantina Institute, Therapeutics Research Group, Woolloongabba, Queensland, Australia
| | - Deborah S. Barkauskas
- University of Queensland, University of Queensland Diamantina Institute, Therapeutics Research Group, Woolloongabba, Queensland, Australia
| | - Amy Holmes
- University of South Australia, Basil Hetzel Institute for Translational Medical Research, The Queen Elizabeth Hospital, School of Pharmacy and Medical Sciences, Adelaide, Australia
| | - Jeffrey Grice
- University of Queensland, University of Queensland Diamantina Institute, Therapeutics Research Group, Woolloongabba, Queensland, Australia
| | - Michael S. Roberts
- University of Queensland, University of Queensland Diamantina Institute, Therapeutics Research Group, Woolloongabba, Queensland, Australia
- University of South Australia, Basil Hetzel Institute for Translational Medical Research, The Queen Elizabeth Hospital, School of Pharmacy and Medical Sciences, Adelaide, Australia
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9
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Lukina MM, Shimolina LE, Kiselev NM, Zagainov VE, Komarov DV, Zagaynova EV, Shirmanova MV. Interrogation of tumor metabolism in tissue samples ex vivo using fluorescence lifetime imaging of NAD(P)H. Methods Appl Fluoresc 2019; 8:014002. [PMID: 31622964 DOI: 10.1088/2050-6120/ab4ed8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Exploring metabolism in human tumors at the cellular level remains a challenge. The reduced form of metabolic cofactor NAD(P)H is one of the major intrinsic fluorescent components in tissues and a valuable indicator of cellular metabolic activity. Fluorescence lifetime imaging (FLIM) enables resolution of both the free and protein-bound fractions of this cofactor, and thus, high sensitivity detection of relative changes in the NAD(P)H-dependent metabolic pathways in real time. However, the clinical use of this technique is still very limited. The applications of metabolic FLIM could be usefully expanded by probing cellular metabolism in tissues ex vivo. For this, however, the development of appropriate tissue preservation protocols is required in order to maintain the optical metabolic characteristics in the ex vivo sample in a state similar to those of the tumor in vivo. Using mouse tumor models of different histological types-colorectal cancer, lung carcinoma and melanoma-we tested eight different methods of tissue handling by comparing NAD(P)H fluorescence decay parameters ex vivo and in vivo as measured with two-photon excited FLIM microscopy. It was found that the samples placed in 10% BSA on ice immediately after excision maintained the same fluorescence lifetimes and free/bound ratios as measured in vivo for at least 3 hours. This protocol was subsequently used for metabolic assessments in fresh postoperative samples from colorectal cancer patients. A high degree of inter- and intra-tumor heterogeneity with a trend to a more oxidative metabolism was detected in T3 colorectal tumors in comparison with normal tumor-distant colon samples. These results suggest that the methodology developed on the basis of FLIM of NAD(P)H in tissues ex vivo show promise for interrogating the metabolic state of patients' tumors.
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Affiliation(s)
- Maria M Lukina
- Privolzhsky Research Medical University, 10/1 Minin and Pozharsky sq., Nizhny Novgorod, 603950, Russia
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10
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Ranawat H, Pal S, Mazumder N. Recent trends in two-photon auto-fluorescence lifetime imaging (2P-FLIM) and its biomedical applications. Biomed Eng Lett 2019; 9:293-310. [PMID: 31456890 PMCID: PMC6694381 DOI: 10.1007/s13534-019-00119-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 05/30/2019] [Accepted: 06/27/2019] [Indexed: 02/07/2023] Open
Abstract
Two photon fluorescence microscopy and the numerous technical advances to it have served as valuable tools in biomedical research. The fluorophores (exogenous or endogenous) absorb light and emit lower energy photons than the absorption energy and the emission (fluorescence) signal is measured using a fluorescence decay graph. Additionally, high spatial resolution images can be acquired in two photon fluorescence lifetime imaging (2P-FLIM) with improved penetration depth which helps in detection of fluorescence signal in vivo. 2P-FLIM is a non-invasive imaging technique in order to visualize cellular metabolic, by tracking intrinsic fluorophores present in it, such as nicotinamide adenine dinucleotide, flavin adenine dinucleotide and tryptophan etc. 2P-FLIM of these molecules enable the visualization of metabolic alterations, non-invasively. This comprehensive review discusses the numerous applications of 2P-FLIM towards cancer, neuro-degenerative, infectious diseases, and wound healing.
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Affiliation(s)
- Harsh Ranawat
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104 India
| | - Sagnik Pal
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104 India
| | - Nirmal Mazumder
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka 576104 India
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11
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Andreana M, Sentosa R, Erkkilä MT, Drexler W, Unterhuber A. Depth resolved label-free multimodal optical imaging platform to study morpho-molecular composition of tissue. Photochem Photobiol Sci 2019; 18:997-1008. [PMID: 30882117 DOI: 10.1039/c8pp00410b] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Multimodal imaging platforms offer a vast array of tissue information in a single image acquisition by combining complementary imaging techniques. By merging different systems, better tissue characterization can be achieved than is possible by the constituent imaging modalities alone. The combination of optical coherence tomography (OCT) with non-linear optical imaging (NLOI) techniques such as two-photon excited fluorescence (TPEF), second harmonic generation (SHG) and coherent anti-Stokes Raman scattering (CARS) provides access to detailed information of tissue structure and molecular composition in a fast, label-free and non-invasive manner. We introduce a multimodal label-free approach for morpho-molecular imaging and spectroscopy and validate the system in mouse skin demonstrating the potential of the system for colocalized acquisition of OCT and NLOI signals.
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Affiliation(s)
- Marco Andreana
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Waehringer Guertel 18-20, 1090 Vienna, Austria.
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12
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Shcheslavskiy VI, Shirmanova MV, Jelzow A, Becker W. Multiparametric Time-Correlated Single Photon Counting Luminescence Microscopy. BIOCHEMISTRY (MOSCOW) 2019; 84:S51-S68. [PMID: 31213195 DOI: 10.1134/s0006297919140049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Classic time-correlated single photon counting (TCSPC) technique involves detection of single photons of a periodic optical signal, registration of the photon arrival time in respect to the reference pulse, and construction of photon distribution with regard to the detection times. This technique achieves extremely high time resolution and near-ideal detection efficiency. Modern TCSPC is multi-dimensional, i.e., in addition to the photon arrival time relative to the excitation pulse, spatial coordinates within the image area, wavelength, time from the start of the experiment, and many other parameters are determined for each photon. Hence, the multi-dimensional TCSPC allows generation of photon distributions over these parameters. This review describes both classic and multi-dimensional types of TCSPC microscopy and their application for fluorescence lifetime imaging in different areas of biological studies.
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Affiliation(s)
- V I Shcheslavskiy
- Becker&Hickl GmbH, Berlin, 12277, Germany. .,Privolzhskiy Medical Research University, Nizhny Novgorod, 603005, Russia
| | - M V Shirmanova
- Privolzhskiy Medical Research University, Nizhny Novgorod, 603005, Russia
| | - A Jelzow
- Becker&Hickl GmbH, Berlin, 12277, Germany
| | - W Becker
- Becker&Hickl GmbH, Berlin, 12277, Germany
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13
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Multispectral Depth-Resolved Fluorescence Lifetime Spectroscopy Using SPAD Array Detectors and Fiber Probes. SENSORS 2019; 19:s19122678. [PMID: 31200569 PMCID: PMC6631026 DOI: 10.3390/s19122678] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 06/10/2019] [Accepted: 06/12/2019] [Indexed: 01/29/2023]
Abstract
Single Photon Avalanche Diode (SPAD) arrays are increasingly exploited and have demonstrated potential in biochemical and biomedical research, both for imaging and single-point spectroscopy applications. In this study, we explore the application of SPADs together with fiber-optic-based delivery and collection geometry to realize fast and simultaneous single-point time-, spectral-, and depth-resolved fluorescence measurements at 375 nm excitation light. Spectral information is encoded across the columns of the array through grating-based dispersion, while depth information is encoded across the rows thanks to a linear arrangement of probe collecting fibers. The initial characterization and validation were realized against layered fluorescent agarose-based phantoms. To verify the practicality and feasibility of this approach in biological specimens, we measured the fluorescence signature of formalin-fixed rabbit aorta samples derived from an animal model of atherosclerosis. The initial results demonstrate that this detection configuration can report fluorescence spectral and lifetime contrast originating at different depths within the specimens. We believe that our optical scheme, based on SPAD array detectors and fiber-optic probes, constitute a powerful and versatile approach for the deployment of multidimensional fluorescence spectroscopy in clinical applications where information from deeper tissue layers is important for diagnosis.
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14
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Haridass IN, Wei JCJ, Mohammed YH, Crichton ML, Anderson CD, Henricson J, Sanchez WY, Meliga SC, Grice JE, Benson HAE, Kendall MAF, Roberts MS. Cellular metabolism and pore lifetime of human skin following microprojection array mediation. J Control Release 2019; 306:59-68. [PMID: 31121279 DOI: 10.1016/j.jconrel.2019.05.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 04/11/2019] [Accepted: 05/14/2019] [Indexed: 01/13/2023]
Abstract
Skin-targeting microscale medical devices are becoming popular for therapeutic delivery and diagnosis. We used cryo-SEM, fluorescence lifetime imaging microscopy (FLIM), autofluorescence imaging microscopy and inflammatory response to study the puncturing and recovery of human skin ex vivo and in vivo after discretised puncturing by a microneedle array (Nanopatch®). Pores induced by the microprojections were found to close by ~25% in diameter within the first 30 min, and almost completely close by ~6 h. FLIM images of ex vivo viable epidermis showed a stable fluorescence lifetime for unpatched areas of ~1000 ps up to 24 h. Only the cells in the immediate puncture zones (in direct contact with projections) showed a reduction in the observed fluorescence lifetimes to between ~518-583 ps. The ratio of free-bound NAD(P)H (α1/α2) in unaffected areas of the viable epidermis was ~2.5-3.0, whereas the ratio at puncture holes was almost double at ~4.2-4.6. An exploratory pilot in vivo study also suggested similar closure rate with histamine administration to the forearms of human volunteers after Nanopatch® treatment, although a prolonged inflammation was observed with Tissue Viability Imaging. Overall, this work shows that the pores created by the microneedle-type medical device, Nanopatch®, are transient, with the skin recovering rapidly within 1-2 days in the epidermis after application.
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Affiliation(s)
- Isha N Haridass
- Curtin Health Innovation Research Institute, School of Pharmacy and Biomedical Sciences, Curtin University, Bentley, WA 6102, Australia; Therapeutics Research Centre, Faculty of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD 4102, Australia
| | - Jonathan C J Wei
- Therapeutics Research Centre, Faculty of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD 4102, Australia; Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, Delft University of Technology, 2628, CD, Delft, the Netherlands
| | - Yousuf H Mohammed
- Therapeutics Research Centre, Faculty of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD 4102, Australia
| | - Michael L Crichton
- Institute of Mechanical, Process and Energy Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Christopher D Anderson
- Department of Clinical and Experimental Medicine, Linköping University, 581 83 Linköping, Sweden
| | - Joakim Henricson
- Division of Drug Research, Department of Medical and Health Sciences, Faculty of Health Sciences Linköping University, Department of Emergency Medicine Local Health Care Services in Central Östergötland, Region Östergötland, Sweden
| | - Washington Y Sanchez
- Therapeutics Research Centre, Faculty of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD 4102, Australia
| | - Stefano C Meliga
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Jeffrey E Grice
- Therapeutics Research Centre, Faculty of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD 4102, Australia
| | - Heather A E Benson
- Curtin Health Innovation Research Institute, School of Pharmacy and Biomedical Sciences, Curtin University, Bentley, WA 6102, Australia
| | - Mark A F Kendall
- Australian National University, Canberra, ACT 0200, Australia; Faculty of Medicine, The University of Queensland, Royal Brisbane and Women's Hospital, Herston, QLD 4006, Australia
| | - Michael S Roberts
- Therapeutics Research Centre, Faculty of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD 4102, Australia; School of Pharmacy and Medical Sciences, University of South Australia, Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5011, Australia.
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15
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Support for the Safe Use of Zinc Oxide Nanoparticle Sunscreens: Lack of Skin Penetration or Cellular Toxicity after Repeated Application in Volunteers. J Invest Dermatol 2019; 139:308-315. [DOI: 10.1016/j.jid.2018.08.024] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 08/08/2018] [Accepted: 08/23/2018] [Indexed: 01/12/2023]
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16
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A new dynamic culture device suitable for rat skin culture. Cell Tissue Res 2018; 375:723-731. [PMID: 30392145 DOI: 10.1007/s00441-018-2945-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 10/02/2018] [Indexed: 10/27/2022]
Abstract
Cultured skin has been used extensively for testing therapeutic drugs because it replicates the physical and biochemical properties of whole skin. However, traditional static culture cannot fully maintain cell viability and skin morphology because of the limitations involved with nutrient transmission. Here, we develop a new dynamic perfusion platform for skin culture and compare it with a static culture device. Rat skins were cultured in either static or dynamic condition for 0, 3, 6, 9 and 12 days. H&E, periodic acid-Schiff (PAS) and picrosirius red (PSR) staining were used for skin morphology detection, immunostaining against cytokeratin 10 (CK10) for differentiation detection, immunostaining against proliferating cell nuclear antigen (PCNA) for cell proliferation detection and TUNEL staining for apoptosis detection. After culturing for 12 days, the epidermis, basement membrane, hair follicles and connective tissue were disrupted in the static group, whereas these features were preserved in the dynamic group. Moreover, compared to the static group, proliferation in the epidermis and hair follicles was significantly improved and apoptosis in dermis was significantly decreased in the dynamic group. These findings suggest that our device is effective for extending the culture period of rat skin to maintain its characteristics and viability in vitro.
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17
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Hermsmeier M, Jeong S, Yamamoto A, Chen X, Nagavarapu U, Evans CL, Chan KF. Characterization of human cutaneous tissue autofluorescence: implications in topical drug delivery studies with fluorescence microscopy. BIOMEDICAL OPTICS EXPRESS 2018; 9:5400-5418. [PMID: 30460136 PMCID: PMC6238944 DOI: 10.1364/boe.9.005400] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/27/2018] [Accepted: 10/05/2018] [Indexed: 05/04/2023]
Abstract
In pharmacokinetic studies of topical drugs, fluorescence microscopy methods can enable the direct visualization and quantification of fluorescent drugs within the skin. One potential limitation of this approach, however, is the strong endogenous fluorescence of skin tissues that makes straightforward identification of specific drug molecules challenging. To study this effect and quantify endogenous skin fluorescence in the context of topical pharmacokinetics, an integrating sphere-based screening tool was designed to collect fluorescence yield data from human skin specimens. Such information could be utilized to select specific donors in the investigation of drug uptake and distribution. Results indicated human facial skin specimens from a group of more than 35 individuals exhibited an at least 6-fold difference in endogenous fluorescence. In visualizing drug distributions, the negative impact of autofluorescence could be exacerbated in cases where there are overlapping spatial distributions or spectral emission profiles between endogenous fluorophores and the exogenous fluorophore of interest. We demonstrated the feasibility of this approach in measuring the range of tissue endogenous fluorescence and selecting specimens for the study of drug pharmacokinetics with fluorescence microscopy.
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Affiliation(s)
- Maiko Hermsmeier
- BioPharmX, Inc., 1505 Adams Drive Suite D, Menlo Park, CA 94025, USA
| | - Sinyoung Jeong
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Akira Yamamoto
- BioPharmX, Inc., 1505 Adams Drive Suite D, Menlo Park, CA 94025, USA
| | - Xin Chen
- BioPharmX, Inc., 1505 Adams Drive Suite D, Menlo Park, CA 94025, USA
| | - Usha Nagavarapu
- BioPharmX, Inc., 1505 Adams Drive Suite D, Menlo Park, CA 94025, USA
| | - Conor L. Evans
- Wellman Center for Photomedicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Kin F. Chan
- BioPharmX, Inc., 1505 Adams Drive Suite D, Menlo Park, CA 94025, USA
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18
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Small DM, Sanchez WY, Roy SF, Morais C, Brooks HL, Coombes JS, Johnson DW, Gobe GC. N-acetyl-cysteine increases cellular dysfunction in progressive chronic kidney damage after acute kidney injury by dampening endogenous antioxidant responses. Am J Physiol Renal Physiol 2018; 314:F956-F968. [PMID: 29357409 DOI: 10.1152/ajprenal.00057.2017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Oxidative stress and mitochondrial dysfunction exacerbate acute kidney injury (AKI), but their role in any associated progress to chronic kidney disease (CKD) remains unclear. Antioxidant therapies often benefit AKI, but their benefits in CKD are controversial since clinical and preclinical investigations often conflict. Here we examined the influence of the antioxidant N-acetyl-cysteine (NAC) on oxidative stress and mitochondrial function during AKI (20-min bilateral renal ischemia plus reperfusion/IR) and progression to chronic kidney pathologies in mice. NAC (5% in diet) was given to mice 7 days prior and up to 21 days post-IR (21d-IR). NAC treatment resulted in the following: prevented proximal tubular epithelial cell apoptosis at early IR (40-min postischemia), yet enhanced interstitial cell proliferation at 21d-IR; increased transforming growth factor-β1 expression independent of IR time; and significantly dampened nuclear factor-like 2-initiated cytoprotective signaling at early IR. In the long term, NAC enhanced cellular metabolic impairment demonstrated by increased peroxisome proliferator activator-γ serine-112 phosphorylation at 21d-IR. Intravital multiphoton microscopy revealed increased endogenous fluorescence of nicotinamide adenine dinucleotide (NADH) in cortical tubular epithelial cells during ischemia, and at 21d-IR that was not attenuated with NAC. Fluorescence lifetime imaging microscopy demonstrated persistent metabolic impairment by increased free/bound NADH in the cortex at 21d-IR that was enhanced by NAC. Increased mitochondrial dysfunction in remnant tubular cells was demonstrated at 21d-IR by tetramethylrhodamine methyl ester fluorimetry. In summary, NAC enhanced progression to CKD following AKI not only by dampening endogenous cellular antioxidant responses at time of injury but also by enhancing persistent kidney mitochondrial and metabolic dysfunction.
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Affiliation(s)
- David M Small
- Centre for Kidney Disease Research, Faculty of Medicine, Translational Research Institute, University of Queensland , Brisbane , Australia.,Department of Biomedical Engineering, Cornell University , Ithaca, New York
| | - Washington Y Sanchez
- Therapeutics Research Centre, Faculty of Medicine, Translational Research Institute, University of Queensland , Brisbane , Australia
| | - Sandrine F Roy
- Diamantina Institute, Translational Research Institute, University of Queensland , Brisbane , Australia
| | - Christudas Morais
- Centre for Kidney Disease Research, Faculty of Medicine, Translational Research Institute, University of Queensland , Brisbane , Australia
| | - Heddwen L Brooks
- Department of Physiology, University of Arizona , Tucson, Arizona
| | - Jeff S Coombes
- School of Human Movement and Nutrition Sciences, University of Queensland , Brisbane , Australia
| | - David W Johnson
- Centre for Kidney Disease Research, Faculty of Medicine, Translational Research Institute, University of Queensland , Brisbane , Australia.,Department of Nephrology, Princess Alexandra Hospital , Brisbane , Australia
| | - Glenda C Gobe
- Centre for Kidney Disease Research, Faculty of Medicine, Translational Research Institute, University of Queensland , Brisbane , Australia
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19
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Andréo-Filho N, Bim AVK, Kaneko TM, Kitice NA, Haridass IN, Abd E, Santos Lopes P, Thakur SS, Parekh HS, Roberts MS, Grice JE, Benson HA, Leite-Silva VR. Development and Evaluation of Lipid Nanoparticles Containing Natural Botanical Oil for Sun Protection: Characterization and in vitro and in vivo Human Skin Permeation and Toxicity. Skin Pharmacol Physiol 2017; 31:1-9. [DOI: 10.1159/000481691] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 09/15/2017] [Indexed: 01/07/2023]
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20
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Bower AJ, Marjanovic M, Zhao Y, Li J, Chaney EJ, Boppart SA. Label-free in vivo cellular-level detection and imaging of apoptosis. JOURNAL OF BIOPHOTONICS 2017; 10:143-150. [PMID: 27089867 PMCID: PMC5071126 DOI: 10.1002/jbio.201600003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 03/07/2016] [Accepted: 03/23/2016] [Indexed: 05/18/2023]
Abstract
Cell death plays a critical role in health and homeostasis as well as in the pathogenesis and treatment of a broad spectrum of diseases and can be broadly divided into two main categories: apoptosis, or programmed cell death, and necrosis, or acute cell death. While these processes have been characterized extensively in vitro, label-free detection of apoptosis and necrosis at the cellular level in vivo has yet to be shown. In this study, for the first time, fluorescence lifetime imaging microscopy (FLIM) of intracellular reduced nicotinamide adenine dinucleotide (NADH) was utilized to assess the metabolic response of in vivo mouse epidermal keratinocytes following induction of apoptosis and necrosis. Results show significantly elevated levels of both the mean lifetime of NADH and the intracellular ratio of protein bound-to-free NADH in the apoptotic compared to the necrotic tissue. In addition, the longitudinal profiles of these two cell death processes show remarkable differences. By identifying and extracting these temporal metabolic signatures, apoptosis in single cells can be studied in native tissue environments within the living organism.
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Affiliation(s)
- Andrew J Bower
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Marina Marjanovic
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Youbo Zhao
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Joanne Li
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Eric J Chaney
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Stephen A Boppart
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Internal Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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21
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Efficacy, Safety and Targets in Topical and Transdermal Active and Excipient Delivery. PERCUTANEOUS PENETRATION ENHANCERS DRUG PENETRATION INTO/THROUGH THE SKIN 2017. [PMCID: PMC7121119 DOI: 10.1007/978-3-662-53270-6_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
A key requirement for topical and transdermal active delivery is the effective delivery of an active to a desired target site, to achieve both safe and efficacious outcomes. This chapter seeks to explore the importance of the pharmacological, toxicological and therapeutic properties of actives and excipients, as well as the site of action as complementary components in percutaneous absorption. This is crucial for optimized topical and transdermal product design.
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22
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Solomatina AI, Chelushkin PS, Krupenya DV, Podkorytov IS, Artamonova TO, Sizov VV, Melnikov AS, Gurzhiy VV, Koshel EI, Shcheslavskiy VI, Tunik SP. Coordination to Imidazole Ring Switches on Phosphorescence of Platinum Cyclometalated Complexes: The Route to Selective Labeling of Peptides and Proteins via Histidine Residues. Bioconjug Chem 2016; 28:426-437. [DOI: 10.1021/acs.bioconjchem.6b00598] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Anastasia I. Solomatina
- Saint Petersburg State University, Institute of
Chemistry, Universitetskii
prospect. 26, 198504 Saint Petersburg, Russia
| | - Pavel S. Chelushkin
- Saint Petersburg State University, Institute of
Chemistry, Universitetskii
prospect. 26, 198504 Saint Petersburg, Russia
- Institute
of Macromolecular Compounds, Russian Academy of Sciences, Bolshoi
prospect, Vasilievskii Island, 31, 199004 Saint Petersburg, Russia
| | - Dmitrii V. Krupenya
- Saint Petersburg State University, Institute of
Chemistry, Universitetskii
prospect. 26, 198504 Saint Petersburg, Russia
| | - Ivan S. Podkorytov
- Saint Petersburg State University, Biomolecular
NMR Laboratory, Botanicheskaya
Str., 17, 198504 Saint Petersburg, Russia
| | - Tatiana O. Artamonova
- Research
Center of Nanobiotechnologies, Peter the Great Saint Petersburg Polytechnic University, Polytechnicheskaya, 29, 195251 Saint Petersburg, Russia
| | - Vladimir V. Sizov
- Saint Petersburg State University, Institute of
Chemistry, Universitetskii
prospect. 26, 198504 Saint Petersburg, Russia
| | - Alexei S. Melnikov
- Saint Petersburg State University, Department
of Physics, Ulianovskaya
Str., 3, 198504 Saint Petersburg, Russia
- Research
Center of Nanobiotechnologies, Peter the Great Saint Petersburg Polytechnic University, Polytechnicheskaya, 29, 195251 Saint Petersburg, Russia
| | - Vladislav V. Gurzhiy
- Saint Petersburg State University, Institute of Earth Sciences and Biology Department, University embankment. 7/9, 199034 Saint Petersburg, Russia
| | - Elena I. Koshel
- Saint Petersburg State University, Institute of Earth Sciences and Biology Department, University embankment. 7/9, 199034 Saint Petersburg, Russia
| | | | - Sergey P. Tunik
- Saint Petersburg State University, Institute of
Chemistry, Universitetskii
prospect. 26, 198504 Saint Petersburg, Russia
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23
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Blacker TS, Duchen MR. Investigating mitochondrial redox state using NADH and NADPH autofluorescence. Free Radic Biol Med 2016; 100:53-65. [PMID: 27519271 PMCID: PMC5145803 DOI: 10.1016/j.freeradbiomed.2016.08.010] [Citation(s) in RCA: 208] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 08/02/2016] [Accepted: 08/08/2016] [Indexed: 11/27/2022]
Abstract
The redox states of the NAD and NADP pyridine nucleotide pools play critical roles in defining the activity of energy producing pathways, in driving oxidative stress and in maintaining antioxidant defences. Broadly speaking, NAD is primarily engaged in regulating energy-producing catabolic processes, whilst NADP may be involved in both antioxidant defence and free radical generation. Defects in the balance of these pathways are associated with numerous diseases, from diabetes and neurodegenerative disease to heart disease and cancer. As such, a method to assess the abundance and redox state of these separate pools in living tissues would provide invaluable insight into the underlying pathophysiology. Experimentally, the intrinsic fluorescence of the reduced forms of both redox cofactors, NADH and NADPH, has been used for this purpose since the mid-twentieth century. In this review, we outline the modern implementation of these techniques for studying mitochondrial redox state in complex tissue preparations. As the fluorescence spectra of NADH and NADPH are indistinguishable, interpreting the signals resulting from their combined fluorescence, often labelled NAD(P)H, can be complex. We therefore discuss recent studies using fluorescence lifetime imaging microscopy (FLIM) which offer the potential to discriminate between the two separate pools. This technique provides increased metabolic information from cellular autofluorescence in biomedical investigations, offering biochemical insights into the changes in time-resolved NAD(P)H fluorescence signals observed in diseased tissues.
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Affiliation(s)
- Thomas S Blacker
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK; Department of Physics and Astronomy, University College London, London WC1E 6BT, UK
| | - Michael R Duchen
- Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK
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24
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Abd E, Yousef SA, Pastore MN, Telaprolu K, Mohammed YH, Namjoshi S, Grice JE, Roberts MS. Skin models for the testing of transdermal drugs. Clin Pharmacol 2016; 8:163-176. [PMID: 27799831 PMCID: PMC5076797 DOI: 10.2147/cpaa.s64788] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The assessment of percutaneous permeation of molecules is a key step in the evaluation of dermal or transdermal delivery systems. If the drugs are intended for delivery to humans, the most appropriate setting in which to do the assessment is the in vivo human. However, this may not be possible for ethical, practical, or economic reasons, particularly in the early phases of development. It is thus necessary to find alternative methods using accessible and reproducible surrogates for in vivo human skin. A range of models has been developed, including ex vivo human skin, usually obtained from cadavers or plastic surgery patients, ex vivo animal skin, and artificial or reconstructed skin models. Increasingly, largely driven by regulatory authorities and industry, there is a focus on developing standardized techniques and protocols. With this comes the need to demonstrate that the surrogate models produce results that correlate with those from in vivo human studies and that they can be used to show bioequivalence of different topical products. This review discusses the alternative skin models that have been developed as surrogates for normal and diseased skin and examines the concepts of using model systems for in vitro–in vivo correlation and the demonstration of bioequivalence.
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Affiliation(s)
- Eman Abd
- Translational Research Institute, School of Medicine, University of Queensland, Brisbane
| | - Shereen A Yousef
- Translational Research Institute, School of Medicine, University of Queensland, Brisbane
| | - Michael N Pastore
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia
| | - Krishna Telaprolu
- Translational Research Institute, School of Medicine, University of Queensland, Brisbane
| | - Yousuf H Mohammed
- Translational Research Institute, School of Medicine, University of Queensland, Brisbane
| | - Sarika Namjoshi
- Translational Research Institute, School of Medicine, University of Queensland, Brisbane
| | - Jeffrey E Grice
- Translational Research Institute, School of Medicine, University of Queensland, Brisbane
| | - Michael S Roberts
- Translational Research Institute, School of Medicine, University of Queensland, Brisbane; School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia
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25
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Small DM, Sanchez WY, Gobe GC. Intravital Multiphoton Imaging of the Kidney: Tubular Structure and Metabolism. Methods Mol Biol 2016; 1397:155-172. [PMID: 26676133 DOI: 10.1007/978-1-4939-3353-2_12] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Multiphoton microscopy (MPM) allows the visualization of dynamic pathophysiological events in real time in live animals. Intravital imaging can be applied to investigate novel mechanisms and treatments of different forms of kidney disease as well as improve our understanding of normal kidney physiology. Using rodent models, in conjunction with endogenous fluorescence and infused exogenous fluorescent dyes, measurement can be made of renal processes such as glomerular permeability, juxtaglomerular apparatus function, interactions of the tubulointerstitium, tubulovascular interactions, vascular flow rate, and the renin-angiotensin-aldosterone system. Subcellular processes including mitochondrial dynamics, reactive oxygen species production, cytosolic ion concentrations, and death processes of apoptosis and necrosis can also be seen and measured by MPM. The current methods chapter presents an overview of MPM with a focus on techniques for intravital kidney imaging and gives examples of instances where intravital MPM has been utilized to study renal pathophysiology. Suggestions are provided for MPM methods within the confines of intravital microscopy and selected kidney structure. MPM is undoubtedly a powerful new technique for application in experimental nephrology, and we believe it will continue to create new paradigms for understanding and treating kidney disease.
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Affiliation(s)
- David M Small
- Centre for Kidney Disease Research, School of Medicine, Translational Research Institute, The University of Queensland, 37 Kent Street, Woolloongabba, Brisbane, QLD, 4102, Australia
| | - Washington Y Sanchez
- Therapeutics Research Centre, School of Medicine, Translational Research Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Glenda C Gobe
- Centre for Kidney Disease Research, School of Medicine, Translational Research Institute, The University of Queensland, 37 Kent Street, Woolloongabba, Brisbane, QLD, 4102, Australia.
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26
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Leite-Silva V, Sanchez W, Studier H, Liu D, Mohammed Y, Holmes A, Ryan E, Haridass I, Chandrasekaran N, Becker W, Grice J, Benson H, Roberts M. Human skin penetration and local effects of topical nano zinc oxide after occlusion and barrier impairment. Eur J Pharm Biopharm 2016; 104:140-7. [DOI: 10.1016/j.ejpb.2016.04.022] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 04/26/2016] [Accepted: 04/26/2016] [Indexed: 12/26/2022]
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27
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Leite-Silva VR, Liu DC, Sanchez WY, Studier H, Mohammed YH, Holmes A, Becker W, Grice JE, Benson HAE, Roberts MS. Effect of flexing and massage on in vivo human skin penetration and toxicity of zinc oxide nanoparticles. Nanomedicine (Lond) 2016; 11:1193-205. [DOI: 10.2217/nnm-2016-0010] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Aim: We assessed the effects of flexing and massage on human skin penetration and toxicity of topically applied coated and uncoated zinc oxide nanoparticles (˜75 nm) in vivo. Materials & methods: Noninvasive multiphoton tomography with fluorescence lifetime imaging was used to evaluate the penetration of nanoparticles through the skin barrier and cellular apoptosis in the viable epidermis. Results: All nanoparticles applied to skin with flexing and massage were retained in the stratum corneum or skin furrows. No significant penetration into the viable epidermis was seen and no cellular toxicity was detected. Conclusion: Exposure of normal in vivo human skin to these nanoparticles under common in-use conditions of flexing or massage is not associated with significant adverse events.
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Affiliation(s)
- Vânia R Leite-Silva
- Therapeutics Research Centre, School of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD, Australia
- Instituto de Ciências Ambientais Químicas e Farmacêuticas, Universidade Federal de São Paulo, Diadema SP, Brazil
| | - David C Liu
- Therapeutics Research Centre, School of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD, Australia
| | - Washington Y Sanchez
- Therapeutics Research Centre, School of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD, Australia
| | - Hauke Studier
- School of Pharmacy & Medical Sciences, University of South Australia City East Campus, Adelaide, SA, Australia
| | - Yousuf H Mohammed
- Therapeutics Research Centre, School of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD, Australia
| | - Amy Holmes
- School of Pharmacy & Medical Sciences, University of South Australia City East Campus, Adelaide, SA, Australia
| | - Wolfgang Becker
- Becker & Hickl GmbH, Nahmitzer Damm 30, 12277 Berlin, Germany
| | - Jeffrey E Grice
- Therapeutics Research Centre, School of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD, Australia
| | - Heather AE Benson
- School of Pharmacy, CHIRI, Curtin University of Technology, Perth, WA, Australia
| | - Michael S Roberts
- Therapeutics Research Centre, School of Medicine, The University of Queensland, Translational Research Institute, Woolloongabba, QLD, Australia
- School of Pharmacy & Medical Sciences, University of South Australia City East Campus, Adelaide, SA, Australia
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Becker W. Fluorescence lifetime imaging by multi-dimensional time correlated single photon counting. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.medpho.2015.02.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Walsh AJ, Shah AT, Sharick JT, Skala MC. Fluorescence Lifetime Measurements of NAD(P)H in Live Cells and Tissue. SPRINGER SERIES IN CHEMICAL PHYSICS 2015. [DOI: 10.1007/978-3-319-14929-5_14] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Koenig K. Hybrid multiphoton multimodal tomography of in vivo human skin. INTRAVITAL 2014. [DOI: 10.4161/intv.21938] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Blacker TS, Mann ZF, Gale JE, Ziegler M, Bain AJ, Szabadkai G, Duchen MR. Separating NADH and NADPH fluorescence in live cells and tissues using FLIM. Nat Commun 2014; 5:3936. [PMID: 24874098 PMCID: PMC4046109 DOI: 10.1038/ncomms4936] [Citation(s) in RCA: 342] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 04/23/2014] [Indexed: 02/07/2023] Open
Abstract
NAD is a key determinant of cellular energy metabolism. In contrast, its phosphorylated form, NADP, plays a central role in biosynthetic pathways and antioxidant defence. The reduced forms of both pyridine nucleotides are fluorescent in living cells but they cannot be distinguished, as they are spectrally identical. Here, using genetic and pharmacological approaches to perturb NAD(P)H metabolism, we find that fluorescence lifetime imaging (FLIM) differentiates quantitatively between the two cofactors. Systematic manipulations to change the balance between oxidative and glycolytic metabolism suggest that these states do not directly impact NAD(P)H fluorescence decay rates. The lifetime changes observed in cancers thus likely reflect shifts in the NADPH/NADH balance. Using a mathematical model, we use these experimental data to quantify the relative levels of NADH and NADPH in different cell types of a complex tissue, the mammalian cochlea. This reveals NADPH-enriched populations of cells, raising questions about their distinct metabolic roles. NAD and NADP play fundamentally different roles in cellular metabolism, and yet these pyridine nucleotides cannot be distinguished spectroscopically in living cells. Blacker et al. demonstrate that fluorescence lifetime imaging can be used to quantify NADPH/NADH balance in cultured cells and in the mammalian cochlea.
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Affiliation(s)
- Thomas S Blacker
- 1] Centre for Mathematics and Physics in the Life Sciences and Experimental Biology, University College London, London WC1E 6BT, UK [2] Research Department of Cell & Developmental Biology, University College London, London WC1E 6BT, UK [3] Department of Physics and Astronomy, University College London, London WC1E 6BT, UK
| | - Zoe F Mann
- 1] Research Department of Cell & Developmental Biology, University College London, London WC1E 6BT, UK [2] UCL Ear Institute, University College London, London WC1X 8EE, UK
| | - Jonathan E Gale
- 1] Research Department of Cell & Developmental Biology, University College London, London WC1E 6BT, UK [2] UCL Ear Institute, University College London, London WC1X 8EE, UK
| | - Mathias Ziegler
- Department of Molecular Biology, University of Bergen, N-5008 Bergen, Norway
| | - Angus J Bain
- Department of Physics and Astronomy, University College London, London WC1E 6BT, UK
| | - Gyorgy Szabadkai
- 1] Research Department of Cell & Developmental Biology, University College London, London WC1E 6BT, UK [2] Department of Biomedical Sciences, University of Padua and CNR Neuroscience Institute, Padua 35121, Italy [3]
| | - Michael R Duchen
- 1] Research Department of Cell & Developmental Biology, University College London, London WC1E 6BT, UK [2]
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Ebrecht R, Don Paul C, Wouters FS. Fluorescence lifetime imaging microscopy in the medical sciences. PROTOPLASMA 2014; 251:293-305. [PMID: 24390249 DOI: 10.1007/s00709-013-0598-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 12/12/2013] [Indexed: 06/03/2023]
Abstract
The steady improvement in the imaging of cellular processes in living tissue over the last 10-15 years through the use of various fluorophores including organic dyes, fluorescent proteins and quantum dots, has made observing biological events common practice. Advances in imaging and recording technology have made it possible to exploit a fluorophore's fluorescence lifetime. The fluorescence lifetime is an intrinsic parameter that is unique for each fluorophore, and that is highly sensitive to its immediate environment and/or the photophysical coupling to other fluorophores by the phenomenon Förster resonance energy transfer (FRET). The fluorescence lifetime has become an important tool in the construction of optical bioassays for various cellular activities and reactions. The measurement of the fluorescence lifetime is possible in two formats; time domain or frequency domain, each with their own advantages. Fluorescence lifetime imaging applications have now progressed to a state where, besides their utility in cell biological research, they can be employed as clinical diagnostic tools. This review highlights the multitude of fluorophores, techniques and clinical applications that make use of fluorescence lifetime imaging microscopy (FLIM).
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Affiliation(s)
- René Ebrecht
- Department of Neuro- and Sensory Physiology, University Medicine Göttingen, 37073, Göttingen, Germany
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Leite-Silva VR, de Almeida MM, Fradin A, Grice JE, Roberts MS. Delivery of drugs applied topically to the skin. ACTA ACUST UNITED AC 2014. [DOI: 10.1586/edm.12.32] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Miyamoto K, Kudoh H. Quantification and visualization of cellular NAD(P)H in young and aged female facial skin with in vivo two-photon tomography. Br J Dermatol 2014; 169 Suppl 2:25-31. [PMID: 23786617 DOI: 10.1111/bjd.12370] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/22/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND In vivo two-photon tomography is a novel noninvasive three-dimensional optical skin imaging technology with subcellular resolution which enables the sensitive detection of endogenous fluorophores. One of these fluorophores, NAD(P)H (a coenzyme which plays an important role in the release of free energy during glycolysis, and influences filaggrin and lipid synthesis), can be selectively detected in keratinocytes (granular cells) with two-photon tomography. OBJECTIVES To quantify NAD(P)H levels in subsurface human facial skin in vivo as a measure to determine if there are changes with age. METHODS A total of 80 healthy Asian females were enrolled in this study, aged 21-68 years. Measurements were performed on facial skin using in vivo two-photon tomography (DermaInspect/MPTflex™, JenLab GmbH, Jena, Germany). The laser beam scans a skin field of interest in pulses, focused at a depth to reach the granular layer. The near-infrared laser pulses excite the endogenous fluorophores NAD(P)H. Image processing was performed to obtain high-resolution autofluorescence images (optical biopsies) and to quantify the fluorescent grey scale to determine NAD(P)H levels. Additional skin surface measures taken were hydration (corneometer), elasticity (cutometer) and wrinkles (image capture and analysis). RESULTS Statistically significant changes in all measured parameters as a function of age were observed. Most importantly, the mean fluorescent grey scale values for NAD(P)H in the youngest group studied (women in their 20s) was 38.8 (SD ± 12.39), while that of the oldest group studied (women in their 60s) was 32.7 (SD ± 12.47). These NAD(P)H levels are statistically significantly different (P = 0.0078). CONCLUSIONS The level of NAD(P)H in the epidermis is significantly greater in younger vs. older skin in vivo. This likely reflects decreased production and/or increased degradation of NAD(P)H in older skin, possibly as a result of chronological ageing and environmental damage (e.g. photodamage). NAD(P)H levels in epidermal skin may be a useful biomarker of skin ageing in vivo. It is also likely that maintaining NAD(P)H production is a useful approach to maintaining good skin condition and caring for ageing skin.
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Affiliation(s)
- K Miyamoto
- R&D Prestige, P&G Innovation GK, 1-17 Koyo-cho Naka, Higashinada-ku, Kobe 658-0035, Japan.
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Seidenari S, Arginelli F, Dunsby C, French PMW, König K, Magnoni C, Talbot C, Ponti G. Multiphoton laser tomography and fluorescence lifetime imaging of melanoma: morphologic features and quantitative data for sensitive and specific non-invasive diagnostics. PLoS One 2013; 8:e70682. [PMID: 23923016 PMCID: PMC3724798 DOI: 10.1371/journal.pone.0070682] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Accepted: 06/21/2013] [Indexed: 11/19/2022] Open
Abstract
Multiphoton laser tomography (MPT) combined with fluorescence lifetime imaging (FLIM) is a non-invasive imaging technique, based on the study of fluorescence decay times of naturally occurring fluorescent molecules, enabling a non-invasive investigation of the skin with subcellular resolution. The aim of this retrospective observational ex vivo study, was to characterize melanoma both from a morphologic and a quantitative point of view, attaining an improvement in the diagnostic accuracy with respect to dermoscopy. In the training phase, thirty parameters, comprising both cytological descriptors and architectural aspects, were identified. The training set included 6 melanomas with a mean Breslow thickness±S.D. of 0.89±0.48 mm. In the test phase, these parameters were blindly evaluated on a test data set consisting of 25 melanomas, 50 nevi and 50 basal cell carcinomas. Melanomas in the test phase comprised 8 in situ lesions and had a mean thickness±S.D. of 0.77±1.2 mm. Moreover, quantitative FLIM data were calculated for special areas of interest. Melanoma was characterized by the presence of atypical short lifetime cells and architectural disorder, in contrast to nevi presenting typical cells and a regular histoarchitecture. Sensitivity and specificity values for melanoma diagnosis were 100% and 98%, respectively, whereas dermoscopy achieved the same sensitivity, but a lower specificity (82%). Mean fluorescence lifetime values of melanocytic cells did not vary between melanomas and nevi, but significantly differed from those referring to basal cell carcinoma enabling a differential diagnosis based on quantitative data. Data from prospective preoperative trials are needed to confirm if MPT/FLIM could increase diagnostic specificity and thus reduce unnecessary surgical excisions.
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Affiliation(s)
- Stefania Seidenari
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - Federica Arginelli
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - Christopher Dunsby
- Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Paul M. W. French
- Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Karsten König
- Department of Biophotonics and Lasertechnology, Saarland University, Saarbrücken, Germany
- JenLab GmbH, Jena, Germany
| | - Cristina Magnoni
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy
| | - Clifford Talbot
- Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Giovanni Ponti
- Department of Clinical and Diagnostic Medicine and Public Health, University Hospital of Modena and Reggio Emilia, Modena, Italy
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Leite-Silva VR, Lamer ML, Sanchez WY, Liu DC, Sanchez WH, Morrow I, Martin D, Silva HD, Prow TW, Grice JE, Roberts MS. The effect of formulation on the penetration of coated and uncoated zinc oxide nanoparticles into the viable epidermis of human skin in vivo. Eur J Pharm Biopharm 2013; 84:297-308. [DOI: 10.1016/j.ejpb.2013.01.020] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 01/09/2013] [Accepted: 01/29/2013] [Indexed: 02/04/2023]
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Balu M, Mazhar A, Hayakawa CK, Mittal R, Krasieva TB, König K, Venugopalan V, Tromberg BJ. In vivo multiphoton NADH fluorescence reveals depth-dependent keratinocyte metabolism in human skin. Biophys J 2013; 104:258-67. [PMID: 23332078 DOI: 10.1016/j.bpj.2012.11.3809] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 11/19/2012] [Accepted: 11/26/2012] [Indexed: 11/26/2022] Open
Abstract
We employ a clinical multiphoton microscope to monitor in vivo and noninvasively the changes in reduced nicotinamide adenine dinucleotide (NADH) fluorescence of human epidermal cells during arterial occlusion. We correlate these results with measurements of tissue oxy- and deoxyhemoglobin concentration during oxygen deprivation using spatial frequency domain imaging. During arterial occlusion, a decrease in oxyhemoglobin corresponds to an increase in NADH fluorescence in the basal epidermal cells, implying a reduction in basal cell oxidative phosphorylation. The ischemia-induced oxygen deprivation is associated with a strong increase in NADH fluorescence of keratinocytes in layers close to the stratum basale, whereas keratinocytes from epidermal layers closer to the skin surface are not affected. Spatial frequency domain imaging optical property measurements, combined with a multilayer Monte Carlo-based radiative transport model of multiphoton microscopy signal collection in skin, establish that localized tissue optical property changes during occlusion do not impact the observed NADH signal increase. This outcome supports the hypothesis that the vascular contribution to the basal layer oxygen supply is significant and these cells engage in oxidative metabolism. Keratinocytes in the more superficial stratum granulosum are either supplied by atmospheric oxygen or are functionally anaerobic. Based on combined hemodynamic and two-photon excited fluorescence data, the oxygen consumption rate in the stratum basale is estimated to be ∼0.035 μmoles/10(6) cells/h.
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Affiliation(s)
- Mihaela Balu
- Laser Microbeam and Medical Program, Beckman Laser Institute and Medical Clinic, University of California, Irvine, California, USA
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Zhu X, Lin L, Yu H, Zhuo S, Chen J, Liu J, Wang Y. Visualization of epidermal and dermal alteration in papulonodular mucinosis by multiphoton microscopy. SCANNING 2013; 35:22-27. [PMID: 22689533 DOI: 10.1002/sca.21031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 04/26/2012] [Indexed: 06/01/2023]
Abstract
Papulonodular mucinosis (PM) is a cutaneous clue to the presence and activity of silent lupus erythematosus (LE), but the exact pathogenesis is still under secret. Moreover, the currently available treatments for PM are not satisfactory. To demonstrate the possibility of multiphoton microscopy (MPM) to trace the pathological state of PM and evaluate the treatment efficacy, epidermal and dermal alteration in skin lesion with PM before and after treatment was examined using MPM. Microstructure of epidermis as well as content and distribution of collagen and elastin in dermis were quantified to characterize the pathological states of PM. The results showed significant morphological difference between skin lesion before and after treatment, indicating the possibility of MPM to assess the therapeutic efficacy. With the advancement on MPM miniaturization and enhancement of contrast and depth of imaging, the MPM technique can be applied in in vivo tracking PM formation and progression, and leading the better understanding the PM pathogenesis and mechanism of response to any treatment, helping to establish novel effective therapies for PM.
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Affiliation(s)
- Xiaoqin Zhu
- Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Normal University, Fuzhou, People's Republic of China
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Prow TW. Multiphoton microscopy applications in nanodermatology. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2012; 4:680-90. [DOI: 10.1002/wnan.1189] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Patalay R, Talbot C, Alexandrov Y, Lenz MO, Kumar S, Warren S, Munro I, Neil MAA, König K, French PMW, Chu A, Stamp GWH, Dunsby C. Multiphoton multispectral fluorescence lifetime tomography for the evaluation of basal cell carcinomas. PLoS One 2012; 7:e43460. [PMID: 22984428 PMCID: PMC3439453 DOI: 10.1371/journal.pone.0043460] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 07/25/2012] [Indexed: 11/19/2022] Open
Abstract
We present the first detailed study using multispectral multiphoton fluorescence lifetime imaging to differentiate basal cell carcinoma cells (BCCs) from normal keratinocytes. Images were acquired from 19 freshly excised BCCs and 27 samples of normal skin (in & ex vivo). Features from fluorescence lifetime images were used to discriminate BCCs with a sensitivity/specificity of 79%/93% respectively. A mosaic of BCC fluorescence lifetime images covering >1 mm2 is also presented, demonstrating the potential for tumour margin delineation. Using 10,462 manually segmented cells from the image data, we quantify the cellular morphology and spectroscopic differences between BCCs and normal skin for the first time. Statistically significant increases were found in the fluorescence lifetimes of cells from BCCs in all spectral channels, ranging from 19.9% (425–515 nm spectral emission) to 39.8% (620–655 nm emission). A discriminant analysis based diagnostic algorithm allowed the fraction of cells classified as malignant to be calculated for each patient. This yielded a receiver operator characteristic area under the curve for the detection of BCC of 0.83. We have used both morphological and spectroscopic parameters to discriminate BCC from normal skin, and provide a comprehensive base for how this technique could be used for BCC assessment in clinical practice.
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Affiliation(s)
- Rakesh Patalay
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
- Department of Dermatology, Imperial College Healthcare NHS Trust, London, United Kingdom
| | - Clifford Talbot
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Yuriy Alexandrov
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Martin O. Lenz
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Sunil Kumar
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Sean Warren
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Ian Munro
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Mark A. A. Neil
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | | | - Paul M. W. French
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Anthony Chu
- Department of Dermatology, Imperial College Healthcare NHS Trust, London, United Kingdom
| | | | - Chris Dunsby
- Photonics Group, Department of Physics, Imperial College London, South Kensington Campus, London, United Kingdom
- Department of Medicine, Imperial College Healthcare NHS Trust, London, United Kingdom
- * E-mail:
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Seidenari S, Arginelli F, Dunsby C, French P, König K, Magnoni C, Manfredini M, Talbot C, Ponti G. Multiphoton laser tomography and fluorescence lifetime imaging of basal cell carcinoma: morphologic features for non-invasive diagnostics. Exp Dermatol 2012; 21:831-6. [PMID: 22882324 DOI: 10.1111/j.1600-0625.2012.01554.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/19/2012] [Indexed: 11/28/2022]
Abstract
Multiphoton laser tomography (MPT) combined with fluorescence lifetime imaging (FLIM) is a non-invasive imaging technique, which gives access to the cellular and extracellular morphology of the skin. The aim of our study was to assess the sensitivity and specificity of MPT/FLIM descriptors for basal cell carcinoma (BCC), to improve BCC diagnosis and the identification of tumor margins. In the preliminary study, FLIM images referring to 35 BCCs and 35 healthy skin samples were evaluated for the identification of morphologic descriptors characteristic of BCC. In the main study, the selected parameters were blindly evaluated on a test set comprising 63 BCCs, 63 healthy skin samples and 66 skin lesions. Moreover, FLIM values inside a region of interest were calculated on 98 healthy skin and 98 BCC samples. In the preliminary study, three epidermal descriptors and 7 BCC descriptors were identified. The specificity of the diagnostic criteria versus 'other lesions' was extremely high, indicating that the presence of at least one BCC descriptor makes the diagnosis of 'other lesion' extremely unlikely. FLIM values referring to BCC cells significantly differed from those of healthy skin. In this study, we identified morphological and numerical descriptors enabling the differentiation of BCC from other skin disorders and its distinction from healthy skin in ex vivo samples. In future, MPT/FLIM may be applied to skin lesions to provide direct clinical guidance before biopsy and histological examination and for the identification of tumor margins allowing a complete surgical removal.
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Affiliation(s)
- Stefania Seidenari
- Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy.
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Pappinen S, Pryazhnikov E, Khiroug L, Ericson MB, Yliperttula M, Urtti A. Organotypic cell cultures and two-photon imaging: Tools for in vitro and in vivo assessment of percutaneous drug delivery and skin toxicity. J Control Release 2012; 161:656-67. [DOI: 10.1016/j.jconrel.2012.03.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Revised: 03/05/2012] [Accepted: 03/06/2012] [Indexed: 12/14/2022]
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Zhao Y, Graf BW, Chaney EJ, Mahmassani Z, Antoniadou E, DeVolder R, Kong H, Boppart MD, Boppart SA. Integrated multimodal optical microscopy for structural and functional imaging of engineered and natural skin. JOURNAL OF BIOPHOTONICS 2012; 5:437-48. [PMID: 22371330 PMCID: PMC4486208 DOI: 10.1002/jbio.201200003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 02/07/2012] [Accepted: 02/07/2012] [Indexed: 05/21/2023]
Abstract
An integrated multimodal optical microscope is demonstrated for high-resolution, structural and functional imaging of engineered and natural skin. This microscope incorporates multiple imaging modalities including optical coherence (OCM), multi-photon (MPM), and fluorescence lifetime imaging microscopy (FLIM), enabling simultaneous visualization of multiple contrast sources and mechanisms from cells and tissues. Spatially co-registered OCM/MPM/FLIM images of multi-layered skin tissues are obtained, which are formed based on complementary information provided by different modalities, i.e., scattering information from OCM, molecular information from MPM, and functional cellular metabolism states from FLIM. Cellular structures in both the dermis and epidermis, especially different morphological and physiological states of keratinocytes from different epidermal layers, are revealed by mutually-validating images. In vivo imaging of human skin is also investigated, which demonstrates the potential of multimodal microscopy for in vivo investigation during engineered skin engraftment. This integrated imaging technique and microscope show the potential for investigating cellular dynamics in developing engineered skin and following in vivo grafting, which will help refine the control and culturing conditions necessary to obtain more robust and physiologically-relevant engineered skin substitutes.
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Affiliation(s)
- Youbo Zhao
- Biophotonics Imaging Laboratory, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Benedikt W. Graf
- Biophotonics Imaging Laboratory, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Eric J. Chaney
- Biophotonics Imaging Laboratory, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Ziad Mahmassani
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Eleni Antoniadou
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Ross DeVolder
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Hyunjoon Kong
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Marni D. Boppart
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Stephen A. Boppart
- Biophotonics Imaging Laboratory, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Internal Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Corresponding author: , Phone: +1 217 244 7479, Fax: +1 217 333 5833
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Multiphoton microscopy. a powerful tool in skin research and topical drug delivery science. J Drug Deliv Sci Technol 2012. [DOI: 10.1016/s1773-2247(12)50036-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Patalay R, Talbot C, Alexandrov Y, Munro I, Neil MAA, König K, French PMW, Chu A, Stamp GW, Dunsby C. Quantification of cellular autofluorescence of human skin using multiphoton tomography and fluorescence lifetime imaging in two spectral detection channels. BIOMEDICAL OPTICS EXPRESS 2011; 2:3295-3308. [PMID: 22162820 PMCID: PMC3233249 DOI: 10.1364/boe.2.003295] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 10/07/2011] [Accepted: 10/13/2011] [Indexed: 05/29/2023]
Abstract
We explore the diagnostic potential of imaging endogenous fluorophores using two photon microscopy and fluorescence lifetime imaging (FLIM) in human skin with two spectral detection channels. Freshly excised benign dysplastic nevi (DN) and malignant nodular Basal Cell Carcinomas (nBCCs) were excited at 760 nm. The resulting fluorescence signal was binned manually on a cell by cell basis. This improved the reliability of fitting using a double exponential decay model and allowed the fluorescence signatures from different cell populations within the tissue to be identified and studied. We also performed a direct comparison between different diagnostic groups. A statistically significant difference between the median mean fluorescence lifetime of 2.79 ns versus 2.52 ns (blue channel, 300-500 nm) and 2.08 ns versus 1.33 ns (green channel, 500-640 nm) was found between nBCCs and DN respectively, using the Mann-Whitney U test (p < 0.01). Further differences in the distribution of fluorescence lifetime parameters and inter-patient variability are also discussed.
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Affiliation(s)
- Rakesh Patalay
- Department of Photonics, Imperial College, South Kensington, Exhibition Road, London, UK
- Department of Dermatology, Imperial College Healthcare NHS Trust, Du Cane Road, London, UK
| | - Clifford Talbot
- Department of Photonics, Imperial College, South Kensington, Exhibition Road, London, UK
| | - Yuriy Alexandrov
- Department of Photonics, Imperial College, South Kensington, Exhibition Road, London, UK
| | - Ian Munro
- Department of Photonics, Imperial College, South Kensington, Exhibition Road, London, UK
| | - Mark A. A. Neil
- Department of Photonics, Imperial College, South Kensington, Exhibition Road, London, UK
| | | | - Paul M. W. French
- Department of Photonics, Imperial College, South Kensington, Exhibition Road, London, UK
| | - Anthony Chu
- Department of Dermatology, Imperial College Healthcare NHS Trust, Du Cane Road, London, UK
| | - Gordon W. Stamp
- CRUK London Research Institute, 44 Lincoln's Inn Fields, London, UK
| | - Chris Dunsby
- Department of Photonics, Imperial College, South Kensington, Exhibition Road, London, UK
- Department of Medicine, Imperial College Healthcare NHS Trust, Du Cane Road, London, UK
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Thorling CA, Liu X, Burczynski FJ, Fletcher LM, Gobe GC, Roberts MS. Multiphoton microscopy can visualize zonal damage and decreased cellular metabolic activity in hepatic ischemia-reperfusion injury in rats. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:116011. [PMID: 22112116 DOI: 10.1117/1.3647597] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Ischemia-reperfusion (I/R) injury is a common occurrence in liver surgery. In orthotopic transplantation, the donor liver is exposed to periods of ischemia and when oxygenated blood is reintroduced to the liver, oxidative stress may develop and lead to graft failure. The aim of this project was to investigate whether noninvasive multiphoton and fluorescence lifetime imaging microscopy, without external markers, were useful in detecting early liver damage caused by I/R injury. Localized hepatic ischemia was induced in rats for 1 h followed by 4 h reperfusion. Multiphoton and fluorescence lifetime imaging microscopy was conducted prior to ischemia and up to 4 h of reperfusion and compared to morphological and biochemical assessment of liver damage. Liver function was significantly impaired at 2 and 4 h of reperfusion. Multiphoton microscopy detected liver damage at 1 h of reperfusion, manifested by vacuolated cells and heterogeneous spread of damage over the liver. The damage was mainly localized in the midzonal region of the liver acinus. In addition, fluorescence lifetime imaging showed a decrease in cellular metabolic activity. Multiphoton and fluorescence lifetime imaging microscopy detected evidence of early I/R injury both structurally and functionally. This provides a simple noninvasive technique useful for following progressive liver injury without external markers.
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Affiliation(s)
- Camilla A Thorling
- The University of Queensland, School of Medicine, Woolloongabba, Queensland, 4102, Australia
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