Cargando…

A novel method for determining murine skeletal muscle fiber type using autofluorescence lifetimes

This work describes a simple way to identify fiber types in living muscles by fluorescence lifetime imaging microscopy (FLIM). We quantified the mean values of lifetimes τ(1) and τ(2) derived from a two-exponential fit in freshly dissected mouse flexor digitorum brevis (FDB) and soleus muscles. Whil...

Descripción completa

Detalles Bibliográficos
Autores principales: Manno, Carlo, Tammineni, Eshwar, Figueroa, Lourdes, Oropeza-Almazán, Yuriana, Rios, Eduardo
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Rockefeller University Press 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9272018/
https://www.ncbi.nlm.nih.gov/pubmed/35796671
http://dx.doi.org/10.1085/jgp.202213143
_version_ 1784744804050010112
author Manno, Carlo
Tammineni, Eshwar
Figueroa, Lourdes
Oropeza-Almazán, Yuriana
Rios, Eduardo
author_facet Manno, Carlo
Tammineni, Eshwar
Figueroa, Lourdes
Oropeza-Almazán, Yuriana
Rios, Eduardo
author_sort Manno, Carlo
collection PubMed
description This work describes a simple way to identify fiber types in living muscles by fluorescence lifetime imaging microscopy (FLIM). We quantified the mean values of lifetimes τ(1) and τ(2) derived from a two-exponential fit in freshly dissected mouse flexor digitorum brevis (FDB) and soleus muscles. While τ(1) values changed following a bimodal behavior between muscles, the distribution of τ(2) is shifted to higher values in FDB. To understand the origin of this difference, we obtained maps of autofluorescence lifetimes of flavin mononucleotide and dinucleotide (FMN/FAD) in cryosections, where excitation was set at 440 nm and emission at a bandwidth of between 500 and 570 nm, and paired them with immunofluorescence images of myosin heavy chain isoforms, which allowed identification of fiber types. In soleus, τ(2) was 3.16 ns for type I (SD 0.11, 97 fibers), 3.45 ns for IIA (0.10, 69), and 3.46 ns for IIX (0.12, 65). In FDB muscle, τ(2) was 3.17 ns for type I (0.08, 22), 3.46 ns for IIA (0.16, 48), and 3.66 ns for IIX (0.15, 43). From τ(2) distributions, it follows that an FDB fiber with τ(2) > 3.3 ns is expected to be of type II, and of type I otherwise. This simple classification method has first and second kind errors estimated at 0.02 and 0.10, which can be lowered by reducing the threshold for identification of type I and increasing it for type II. Lifetime maps of autofluorescence, therefore, constitute a tool to identify fiber types that, for being practical, fast, and noninvasive, can be applied in living tissue without compromising other experimental interventions.
format Online
Article
Text
id pubmed-9272018
institution National Center for Biotechnology Information
language English
publishDate 2022
publisher Rockefeller University Press
record_format MEDLINE/PubMed
spelling pubmed-92720182023-01-07 A novel method for determining murine skeletal muscle fiber type using autofluorescence lifetimes Manno, Carlo Tammineni, Eshwar Figueroa, Lourdes Oropeza-Almazán, Yuriana Rios, Eduardo J Gen Physiol Methods and Approaches This work describes a simple way to identify fiber types in living muscles by fluorescence lifetime imaging microscopy (FLIM). We quantified the mean values of lifetimes τ(1) and τ(2) derived from a two-exponential fit in freshly dissected mouse flexor digitorum brevis (FDB) and soleus muscles. While τ(1) values changed following a bimodal behavior between muscles, the distribution of τ(2) is shifted to higher values in FDB. To understand the origin of this difference, we obtained maps of autofluorescence lifetimes of flavin mononucleotide and dinucleotide (FMN/FAD) in cryosections, where excitation was set at 440 nm and emission at a bandwidth of between 500 and 570 nm, and paired them with immunofluorescence images of myosin heavy chain isoforms, which allowed identification of fiber types. In soleus, τ(2) was 3.16 ns for type I (SD 0.11, 97 fibers), 3.45 ns for IIA (0.10, 69), and 3.46 ns for IIX (0.12, 65). In FDB muscle, τ(2) was 3.17 ns for type I (0.08, 22), 3.46 ns for IIA (0.16, 48), and 3.66 ns for IIX (0.15, 43). From τ(2) distributions, it follows that an FDB fiber with τ(2) > 3.3 ns is expected to be of type II, and of type I otherwise. This simple classification method has first and second kind errors estimated at 0.02 and 0.10, which can be lowered by reducing the threshold for identification of type I and increasing it for type II. Lifetime maps of autofluorescence, therefore, constitute a tool to identify fiber types that, for being practical, fast, and noninvasive, can be applied in living tissue without compromising other experimental interventions. Rockefeller University Press 2022-07-07 /pmc/articles/PMC9272018/ /pubmed/35796671 http://dx.doi.org/10.1085/jgp.202213143 Text en © 2022 Manno et al. https://creativecommons.org/licenses/by-nc-sa/4.0/http://www.rupress.org/terms/This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms/). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 International license, as described at https://creativecommons.org/licenses/by-nc-sa/4.0/).
spellingShingle Methods and Approaches
Manno, Carlo
Tammineni, Eshwar
Figueroa, Lourdes
Oropeza-Almazán, Yuriana
Rios, Eduardo
A novel method for determining murine skeletal muscle fiber type using autofluorescence lifetimes
title A novel method for determining murine skeletal muscle fiber type using autofluorescence lifetimes
title_full A novel method for determining murine skeletal muscle fiber type using autofluorescence lifetimes
title_fullStr A novel method for determining murine skeletal muscle fiber type using autofluorescence lifetimes
title_full_unstemmed A novel method for determining murine skeletal muscle fiber type using autofluorescence lifetimes
title_short A novel method for determining murine skeletal muscle fiber type using autofluorescence lifetimes
title_sort novel method for determining murine skeletal muscle fiber type using autofluorescence lifetimes
topic Methods and Approaches
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9272018/
https://www.ncbi.nlm.nih.gov/pubmed/35796671
http://dx.doi.org/10.1085/jgp.202213143
work_keys_str_mv AT mannocarlo anovelmethodfordeterminingmurineskeletalmusclefibertypeusingautofluorescencelifetimes
AT tamminenieshwar anovelmethodfordeterminingmurineskeletalmusclefibertypeusingautofluorescencelifetimes
AT figueroalourdes anovelmethodfordeterminingmurineskeletalmusclefibertypeusingautofluorescencelifetimes
AT oropezaalmazanyuriana anovelmethodfordeterminingmurineskeletalmusclefibertypeusingautofluorescencelifetimes
AT rioseduardo anovelmethodfordeterminingmurineskeletalmusclefibertypeusingautofluorescencelifetimes
AT mannocarlo novelmethodfordeterminingmurineskeletalmusclefibertypeusingautofluorescencelifetimes
AT tamminenieshwar novelmethodfordeterminingmurineskeletalmusclefibertypeusingautofluorescencelifetimes
AT figueroalourdes novelmethodfordeterminingmurineskeletalmusclefibertypeusingautofluorescencelifetimes
AT oropezaalmazanyuriana novelmethodfordeterminingmurineskeletalmusclefibertypeusingautofluorescencelifetimes
AT rioseduardo novelmethodfordeterminingmurineskeletalmusclefibertypeusingautofluorescencelifetimes