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ARS Home » Southeast Area » Little Rock, Arkansas » Arkansas Children's Nutrition Center » Microbiome and Metabolism Research » Research » Publications at this Location » Publication #419553
Research Project: Impact of Maternal Influence and Early Dietary Factors on Child Growth, Development, and Metabolic Health

Location: Microbiome and Metabolism Research

Title: Mitochondria Content Markers vs. Number Via Electron Microscopy in Placenta of Women with Obesity

Author
item RIVERA, JENY - Arkansas Children'S Nutrition Research Center (ACNC)
item ANDRES, ALINE - Arkansas Children'S Nutrition Research Center (ACNC)
item PORTER, CRAIG - Arkansas Children'S Nutrition Research Center (ACNC)
item WHANKHADE, UMESH - Arkansas Children'S Nutrition Research Center (ACNC)
item SE-RAN, JUN - University Arkansas For Medical Sciences (UAMS)
item BØRSHEIM, ELISABET - Arkansas Children'S Nutrition Research Center (ACNC)
item DIAZ, EVA - Arkansas Children'S Nutrition Research Center (ACNC)

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/22/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Background. Citrate synthase activity (CSa) is used for normalizing mitochondrial number. In high-resolution respirometry (HRR), flux control rations (oxygen flux/complex IV activity) are used to account for mitochondrial content. This study evaluated the correlation of mitochondria number with CSa, complex (C) IV activity, and other HRR measurements in placenta (PL). Methods. Women (n=13) with obesity participated in the control arm of two randomized controlled trials with identical inclusion and exclusion criteria. PL was collected at delivery and CSa measured using an enzymatic assay kit. CSa (nmol·min-1'mg-1) was normalized for protein content. PL mitochondria respiration was measured in permeabilized fibers using HRR (pmol O2·s-1·mg-1): CI-leak (L, pyruvate & malate), OXPHOS capacity of CI-linked activity (P, ADP), maximal respiration (E, CCCP) uncoupled CI-respiration (CIE, glutamate), uncoupled CI&CII respiration (CIE&IIE, succinate), CII-linked ETS-capacity (CIIE, rotenone), residual oxygen consumption (ROX, antimycin), and CIV activity (CIV). The Spearman correlation coefficient measured the correlation of mitochondrial number by TEM with CS and HRR measurements. Results. Participants were 28.9± 4.3 y.o and had a BMI of 36.3 ± 5.0. Infants (females 50%) were born at 272.3 ± 6.1 days of gestational age, and had a weight for gestational age z-score of 0.85±0.52. Mitochondria number by TEM did not correlate with CSa (rho= -0.27, p = 0.364) but correlated with CIV activity (rho= 0.57, p= 0.041). There was no correlation between TEM and other measurements of HRR. Conclusions. CSa was not a reliable surrogate mitochondria content in PL of women with obesity. While CIV activity correlated with mitochondria number measured by TEM, the level of correlation was moderate. Therefore, caution is recommended when CIV activity is used to normalized HRR measurements in PL of women with obesity. NIH-NIGMS award 5P20GM109096, USDA-ARS 6026-51000-012-06S.