Mitochondria from human term placenta. I. Isolation and assay conditions for oxidative phosphorylation

Maternal smoking is associated with mitochondrial DNA depletion and respiratory chain complex III deficiency in placenta

“…Contamination with plasma membrane was found to be Ͻ5% with this method, which did not modify the values of ATP and ADP hydrolysis (28). The method yielded ϳ35 mg of mitochondrial protein from 100 g of wet placental tissue, which agreed with the literature values (12,34,49), and was identical in each clinical group. The mean yield of purified placental mitochondria, based on the activity of citrate synthase, was 11.9 Ϯ 5.7% for both groups.…”

“…Thus the oxygen consumption for each placenta was measured during state 2, state 3, and state 4, and the average oxygen consumption during these states was calculated for the smoking-and nonsmoking-exposed groups. The respiratory control index (RCI) was defined as the ratio of the average state 3 to the average state 4 (12,34).…”

Glutaminolysis in Animal Cells

“…Glutamine and glutamate also caused a small increase in lactate production (Holzman et at., 1979). Glutamate supported oxidative phosphorylation in isolated mitochondria from human placenta (Olivera and Meigs, 1975). Glutamine was the most efficient substrate for ammonia production in isolated placental mitochondria although glutamate also increased ammonia release in the presence of ADP and NADP (Makarewicz and Swierczynski, 1982).…”

The Role of Mitochondria in Syncytiotrophoblast Cells: Bioenergetics and Steroidogenesis

“…The larger cytotrophoblast mitochondria have a round shape, whereas syncytiotrophoblast mitochondria display an irregular shape with protuberances of the outer and inner membranes (De Los Rios Castillo et al, 2011). Isolated cytotrophoblast and syncytiotrophoblast mitochondria showed values for respiratory control higher than those previously reported for this tissue (Olivera & Meigs, 1975) and the oxygen uptake was coupled to ATP synthesis, reaching 151 ± 16 and 153 ± 13 nmol ATP/mg/min, respectively (De Los Rios Castillo et al, 2011). These observations demonstrate the presence of functional mitochondria in both cell types, retaining the ability to increase the consumption of oxygen and the synthesis of ATP upon the addition of ADP.…”