Using laser capture microdissection to study fiber specific signaling in locomotor muscle in COPD: A pilot study.
Quadriceps dysfunction is important in chronic obstructive pulmonary disease (COPD), with an associated increased proportion of type II fibers. Investigation of protein synthesis and degradation has yielded conflicting results, possibly due to study of whole biopsy samples, whereas signaling may be fiber-specific. Our objective was to develop a method for fiber-specific gene expression analysis.



12 COPD and 6 healthy subjects underwent quadriceps biopsy. Cryosections were immunostained for type II fibers, which were separated using laser capture microdissection (LCM). Whole muscle and different fiber populations were subject to quantitative polymerase chain reaction.



Levels of muscle-RING-finger-protein-1 and Atrogin-1 were lower in type II fibers of COPD versus healthy subjects (P = 0.02 and P = 0.03, respectively), but differences were not apparent in whole muscle or type I fibers.



We describe a novel method for studying fiber-specific gene expression in optimum cutting temperature compound-embedded muscle specimens. LCM offers a more sensitive way to identify molecular changes in COPD muscle. Muscle Nerve 55: 902-912, 2017.
NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, London, United Kingdom.
Divya
D
Mohan
Section of Molecular Medicine, National Heart and Lung Institute, Imperial College, London, United Kingdom, SW7 2AZ.
Amy
A
Lewis
NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, London, United Kingdom.
Mehul S
MS
Patel
NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, London, United Kingdom.
Katrina J
KJ
Curtis
Section of Molecular Medicine, National Heart and Lung Institute, Imperial College, London, United Kingdom, SW7 2AZ.
Jen Y
JY
Lee
NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, London, United Kingdom.
Nicholas S
NS
Hopkinson
Clinical Pharmacology Unit, Addenbrookes Hospital, University of Cambridge, Cambridge, United Kingdom.
Ian B
IB
Wilkinson
Section of Molecular Medicine, National Heart and Lung Institute, Imperial College, London, United Kingdom, SW7 2AZ.
Paul R
PR
Kemp
NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, London, United Kingdom.
Michael I
MI
Polkey
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D061346:Laser Capture Microdissection; D008297:Male; D008875:Middle Aged; D018485:Muscle Fibers, Skeletal / Q000145:classification / Q000378:metabolism* / Q000473:pathology; D009124:Muscle Proteins / Q000235:genetics / Q000378:metabolism; D018482:Muscle, Skeletal / Q000503:physiopathology; D018995:Myosin Heavy Chains / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism; D010865:Pilot Projects; D029424:Pulmonary Disease, Chronic Obstructive / Q000473:pathology*; D044843:SKP Cullin F-Box Protein Ligases / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D018709:Statistics, Nonparametric
D047908:Intracellular Signaling Peptides and Proteins; D009124:Muscle Proteins; C440907:FBXO32 protein, human; D044843:SKP Cullin F-Box Protein Ligases; C403446:NMRK2 protein, human; D017853:Phosphotransferases (Alcohol Group Acceptor); D018995:Myosin Heavy Chains
fiber type; humans; microdissection; muscle weakness; quadriceps muscle