TY - JOUR
T1 - Mitochondrial DNA lesions and copy number are strain dependent in endurance-trained mice
AU - Vellers, Heather L.
AU - Massett, Michael P.
AU - Avila, Josh J.
AU - Kim, Seung Kyum
AU - Marzec, Jacqui M.
AU - Santos, Janine H.
AU - Lightfoot, J. Timothy
AU - Kleeberger, Steven R.
N1 - Publisher Copyright:
© 2020 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society
PY - 2020/11
Y1 - 2020/11
N2 - In this pilot work, we selected two inbred strains that respond well to endurance training (ET) (FVB/NJ, and SJL/J strains), and two strains that respond poorly (BALB/cByJ and NZW/LacJ), to determine the effect of a standardized ET treadmill program on mitochondrial and nuclear DNA (nucDNA) integrity, and mitochondrial DNA (mtDNA) copy number. DNA was isolated from plantaris muscles (n = 37) and a gene-specific quantitative PCR-based assay was used to measure DNA lesions and mtDNA copy number. Mean mtDNA lesions were not different within strains in the sedentary or exercise-trained states. However, mtDNA lesions were significantly higher in trained low-responding NZW/LacJ mice (0.24 ± 0.06 mtDNA lesions/10 Kb) compared to high-responding strains (mtDNA lesions/10 Kb: FVB/NJ = 0.11 ± 0.01, p =.049; SJL/J = 0.04 ± 0.02; p =.003). ET did not alter mean mtDNA copy numbers for any strain, although both sedentary and trained FVB/NJ mice had significantly higher mtDNA copies (99,890 ± 4,884 mtDNA copies) compared to low-responding strains (mtDNA copies: BALB/cByJ = 69,744 ± 4,675; NZW/LacJ = 65,687 ± 5,180; p <.001). ET did not change nucDNA lesions for any strain, however, SJL/J had the lowest mean nucDNA lesions (3.5 ± 0.14 nucDNA lesions/6.5 Kb) compared to all other strains (nucDNA lesions/6.5 Kb: FVB/NJ = 4.4 ± 0.11; BALB/cByJ = 4.7 ± 0.09; NZW/LacJ = 4.4 ± 0.11; p <.0001). Our results demonstrate strain differences in plantaris muscle mtDNA lesions in ET mice and, independent of condition, differences in mean mtDNA copy and nucDNA lesions between strains.
AB - In this pilot work, we selected two inbred strains that respond well to endurance training (ET) (FVB/NJ, and SJL/J strains), and two strains that respond poorly (BALB/cByJ and NZW/LacJ), to determine the effect of a standardized ET treadmill program on mitochondrial and nuclear DNA (nucDNA) integrity, and mitochondrial DNA (mtDNA) copy number. DNA was isolated from plantaris muscles (n = 37) and a gene-specific quantitative PCR-based assay was used to measure DNA lesions and mtDNA copy number. Mean mtDNA lesions were not different within strains in the sedentary or exercise-trained states. However, mtDNA lesions were significantly higher in trained low-responding NZW/LacJ mice (0.24 ± 0.06 mtDNA lesions/10 Kb) compared to high-responding strains (mtDNA lesions/10 Kb: FVB/NJ = 0.11 ± 0.01, p =.049; SJL/J = 0.04 ± 0.02; p =.003). ET did not alter mean mtDNA copy numbers for any strain, although both sedentary and trained FVB/NJ mice had significantly higher mtDNA copies (99,890 ± 4,884 mtDNA copies) compared to low-responding strains (mtDNA copies: BALB/cByJ = 69,744 ± 4,675; NZW/LacJ = 65,687 ± 5,180; p <.001). ET did not change nucDNA lesions for any strain, however, SJL/J had the lowest mean nucDNA lesions (3.5 ± 0.14 nucDNA lesions/6.5 Kb) compared to all other strains (nucDNA lesions/6.5 Kb: FVB/NJ = 4.4 ± 0.11; BALB/cByJ = 4.7 ± 0.09; NZW/LacJ = 4.4 ± 0.11; p <.0001). Our results demonstrate strain differences in plantaris muscle mtDNA lesions in ET mice and, independent of condition, differences in mean mtDNA copy and nucDNA lesions between strains.
KW - exercise training
KW - interstrain variation
KW - mtDNA copy number
KW - mtDNA lesions
UR - http://www.scopus.com/inward/record.url?scp=85095938449&partnerID=8YFLogxK
U2 - 10.14814/phy2.14605
DO - 10.14814/phy2.14605
M3 - Article
C2 - 33190396
AN - SCOPUS:85095938449
SN - 2051-817X
VL - 8
JO - Physiological Reports
JF - Physiological Reports
IS - 21
M1 - e14605
ER -