Beta Amyloid Peptide: Research Paper: The feasibility of muscle mitochondrial respiratory chain phenotyping across the cognitive spectrum in Parkinson's disease

The feasibility of muscle mitochondrial respiratory chain phenotyping across the cognitive spectrum in Parkinson's disease

Abstract

Introduction: There has been little work on the relationship between sarcopenia, a progressive skeletal muscle disorder, and age-related neurodegenerative diseases such as Parkinson's disease (PD).

Objectives: We aimed to determine: 1) the feasibility of characterizing skeletal muscle across a range of cognitive function in PD; 2) if muscle mitochondrial respiratory chain (MRC) function and content are preserved in older adults with PD.

Methods: Sarcopenia was defined using handgrip strength, chair rise and bioimpedance analysis. MRC function was assessed using phosphorous magnetic resonance spectroscopy (MRS) by estimating τ1/2 PCr (s) (phosphocreatine half-time recovery) in the calf muscles following a bout of aerobic exercise. Biopsy of the vastus lateralis muscle was performed, and MRC content assessed by fluorescent immunohistochemistry for porin and components of MRC Complexes I and IV.

Results: Nine participants (78% male; mean age 79.9; PD duration 3.3 years) were recruited. Four had cognitive impairment. Six participants had probable sarcopenia. Eight participants completed MRS and had mean (SD) τ1/2 PCr of 37.8 (7.6) seconds, suggesting preserved mitochondrial function. Muscle biopsies were obtained in all and the procedure was well tolerated. Porin Z-score, a proxy for mitochondrial mass, was lower than expected compared to controls (0-89% of fibres with low porin). There was a small amount of Complex I (0.16-4.59%) and Complex IV (0-3.79%) deficiency.

Conclusions: Detailed phenotyping, muscle biopsy and imaging was feasible and acceptable across a spectrum of cognitive function in PD. Sarcopenia was relatively common and may be associated with lower mitochondrial mass and low levels of MRC deficiency.

Keywords: Aging; Cognition; Mitochondrial function; Parkinson's disease; Sarcopenia.

Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.

Conflict of interest statement

Declaration of competing interest The authors report no conflict of interest.

This article originally appeared in the "  https://pubmed.ncbi.nlm.nih.gov/32554091/  " and has their copyrights. We do not claim copyright on the content. This information is for research purposes only. This Blog is made available by publishers for educational purposes only as well as to give you general information and a general understanding , not to provide specific advice. By using this blog site you understand that there is no client relationship between you and the Blog publisher. The Blog should not be used as a substitute for competent research advice.