The correlation of age-related mitochondrial respiratory function of peripheral blood mononuclear cells with grip strength and appendicular skeletal muscle mass / 中华老年医学杂志

ABSTRACT

Objective:To investigate the correlation of mitochondrial respiration function and oxidative phosphorylation of peripheral blood mononuclear cells(PBMCs)with grip strength and muscle mass in the elderly, and to identify potential biomarkers for the diagnosis of sarcopenia.Methods:A total of 65 patients admitted to our hospital from June 2019 to August 2020 were enrolled in this study.PBMCs were extracted from subjects.Mitochondrial oxidative respiration function was assessed via the Seahorse XF24 analyzer.Grip strength was measured using a hydraulic dynamometer, and appendicular skeletal muscle mass(ASM)was estimated by dual-energy X-ray absorptiometry(DXA). Multivariate analysis was conducted by using partial correlation analysis and multiple linear regression, in order to evaluate the correlation of mitochondrial oxidative respiration function with grip strength and ASM.Results:After adjustment for gender and body mass index(BMI), partial correlation analysis showed that grip strength and ASM had a negative correlation with age( r=-0.537 and -0.390, both P<0.001); and basal respiration, maximal respiration, ATP production and spare respiratory capacity of mitochondria in PBMCs were negatively correlated with age( r=-0.558, -0.614, -0.526 and -0.582, all P<0.001), whereas grip strength and ASM were positively correlated with basal respiration, maximal respiration, ATP production, spare respiratory capacity and proton leak of mitochondria in PBMCs(grip strength r=0.414, 0.451, 0.362, 0.420 and 0.425, P=0.002, 0.001, 0.008, 0.002 and 0.002; ASM r=0.319, 0.368, 0.299, 0.352 and 0.279, P=0.019, 0.006, 0.028, 0.009 and 0.041). Multiple linear regression analysis showed that grip strength and ASM were positively correlated with basal respiration, maximal respiration, ATP production, spare respiratory capacity and proton leak of mitochondria in PBMCs(grip β=0.503, 0.548, 0.452, 0.519 and 0.532, t=3.248, 3.604, 2.774, 3.301 and 3.350, P=0.002, 0.001, 0.008, 0.002 and 0.002; ASM β=0.302, 0.355, 0.289, 0.346 and 0.271, t=2.427, 2.856, 2.263, 2.716 and 2.091, P=0.019, 0.006, 0.028, 0.009 and 0.041). Age was negatively correlated with basal respiration, maximal respiration, ATP production and spare respiratory capacity of mitochondria in PBMCs( β=-0.581, -0.654, -0.558 and -0.640, t=-4.285, -5.157, -3.938 and -4.863, all P<0.001). Multiple linear regression analysis showed that ASM and grip strength had no significant correlation with basal respiration, maximal respiration, ATP production, spare respiratory capacity or proton leak of mitochondria in PBMCs. Conclusions:Age-related mitochondrial oxidative respiration in PBMCs can reflect changes in muscle strength and muscle mass and, combined with grip strength and ASM, may be considered as a biomarker for the evaluation of sarcopenia in the elderly.