Kayla Ireland

Melatonin Improves Mitochondrial Respiration in Syncytiotrophoblasts From Placentas of Obese Women

Maternal obesity is associated with increased oxidative stress but decreased placental mitochondrial respiration and expression of mitochondrial electron transport chain (ETC) complexes I to V. Melatonin acts as an antioxidant and prevents oxidative stress-induced changes in cytotrophoblasts. Placentas were collected at term by cesarean delivery from obese (first trimester body mass index [BMI] ≥30, n = 10) or lean (BMI < 25, n = 6) women. Cytotrophoblasts were isolated and allowed to syncytialize for 72 hours with or without melatonin (0.1-100 µM) for the last 24 hours. Mitochondrial respiratory parameters were measured in a Seahorse XF24. Expression of ETC complexes I to V and antioxidant enzymes was measured by Western blot. Maternal clinical characteristics of patients were similar except for BMI. No significant improvement in mitochondrial respiration occurred with addition of melatonin to trophoblasts of lean women. However, in trophoblasts from obese women, melatonin (10 and 100 µmol/L) significantly increased maximal respiration (P = .01 and P = .009, respectively) and spare capacity (P = .02 and P = .003, respectively) compared to the untreated control. No differences were detected in the expression of ETC complexes and superoxide dismutase 1 or 2 in trophoblasts treated with melatonin. The expression of glutathione peroxidase, which was significantly greater in trophoblast of obese compared to lean women (P < .05), was decreased back to the level seen in trophoblast of lean women with addition of melatonin (P = .02). Improved spare respiratory capacity, the cellular reserve, could impart a protective effect to the placenta and fetus in an adverse intrauterine environment or in response to additional stressors.

Intra-amniotic Dye Alternatives for the Diagnosis of Preterm Prelabor Rupture of Membranes

Intra-amniotic dye instillation is a useful tool for evaluation of equivocal cases of preterm prelabor rupture of membranes and for genetic amniocentesis in multifetal gestation. Indigo carmine, the most used and studied dye, is no longer available. We sought to provide a resource of potential dyes for clinical use that summarizes dosing along with maternal, fetal, and neonatal outcomes. We reviewed the literature evaluating the use of alternative agents. Sodium fluorescein has proven clinical usefulness but has side effects when used intravenously. Phenol-sulfonphthalein has reported clinical utility with no cases of maternal, fetal, or neonatal side effects; however, it is not currently available in the United States. Indocyanine green has been used in pregnancy for other indications. Oral phenazopyridine hydrochloride may lead to a false-positive diagnosis of preterm prelabor rupture of membranes. Evans blue and methylene blue have adverse fetal and neonatal effects. Of the dye options available, fluorescein is a readily available commercial option that has the best evidence supporting use and safety for these indications.