TY  - JOUR
TI  - Assessing Mitochondrial Respiratory Complex-Associated Function From Previously Frozen Mouse Placental Tissue
AU  - Podinic, Tina 
AU  - Xhuti, Donald 
AU  - Monaco, Cristina 
AU  - Nederveen, Joshua P.
AU  - Raha, Sandeep 
VL  - 16
IS  - 9
PY  - 2026
DA  - 2026/05/05
SP  - e5667
C1  - Bio-protocol 2026;16:e5667
DO  - 10.21769/BioProtoc.5667
UR  - https://doi.org/10.21769/BioProtoc.5667
AB  - The placenta is a metabolically active organ whose mitochondrial activity is tightly linked to fetal growth, oxygenation, and nutrient transport, mediating fetal susceptibility to environmental exposures. Accordingly, aberrant mitochondrial function has been implicated in the progression of placental dysfunction. However, existing respirometry platforms require primarily fresh or cryopreserved placental tissue and offer limited throughput, rendering these platforms impractical in the context of large-scale placental dissections. Here, we describe and validate a Seahorse XF approach for measuring mitochondrial respiration in previously frozen placentae, enabling the functional interrogation of placental mitochondria in prenatal studies. Our protocol fundamentally relies on the restoration of matrix substrates that are depleted due to increased mitochondrial membrane permeability following freeze-thaw cycles. We provide a strategy to assess complex I and II-associated respiration adapted for the Seahorse XFe24 Analyzer and further demonstrate comparable oxygen consumption readouts between fresh and frozen placentae. We further demonstrate distinct differences in the magnitude of oxygen consumption between fresh and frozen placentae in the absence of exogenous NADH. Taken together, we present a simplified and convenient protocol for the assessment of respiratory enzyme complex-associated respiration from archived placental tissue.
KW  - Placenta
KW  - Mitochondria
KW  - Respirometry
KW  - Metabolism
KW  - Electron transport-chain enzyme activity
KW  - Respiration
KW  - Bioenergetics
KW  - Oxygen consumption
KW  - Fresh tissue
KW  - Frozen tissue
JF  - Bio-protocol
SN  - 2331-8325
PB  - Bio-protocol LLC.
BIO101  - False