Use of estetrol with other steroids for attenuation of neonatal hypoxic-Ischemic brain injury: to combine or not to combine?

Abstract

Estetrol (E4), estradiol (E2) and progesterone (P4) have important antioxidative and neuroprotective effects in neuronal system. We aimed to study the consequence of combined steroid therapy in neonatal hypoxic-ischemic encephalopathy (HIE). In vitro the effect of E4 combined with other steroids on oxidative stress and the cell viability in primary hippocampal cultures was evaluated by lactate dehydrogenase and cell survival assays. In vivo neuroprotective and therapeutic efficacy of E4 combined with other steroids was studied in HIE model of immature rats. The rat pups rectal temperature, body and brain weights were evaluated. The hippocampus and the cortex were investigated by histo/immunohistochemistry: intact cell number counting, expressions of markers for early gray matter lose, neuro- and angiogenesis were studied. Glial fibrillary acidic protein was evaluated by ELISA in blood samples. In vitro E4 and combinations of high doses of E4 with P4 and/or E2 significantly diminished the LDH activity and upregulated the cell survival.In vivopretreatment or treatment by different combinations of E4 with other steroids had unalike effects on body and brain weight, neuro- and angiogenesis, and GFAP expression in blood. The combined use of E4 with other steroids has no benefit over the single use of E4.

Estrogen receptors and estetrol-dependent neuroprotective actions: a pilot study

“…2012), which we have used in our previous study (Tskitishvili et al . 2014, 2016). Briefly, brains were dissected to separate the hippocampus region.…”

“…E4 (Mithra Pharmaceuticals, Liege, Belgium) was used at a concentration of 3.25 mM as one of the successful concentrations used in our previous in vitro studies (Tskitishvili et al . 2014, 2016). LDH activity was measured in supernatants.…”

“…All the procedures were performed in accordance to the manufacturer’s protocol as previously described (Tskitishvili et al . 2014, 2016). Each condition was repeated 3–6 times.…”

“…Hypoxia was produced by the inhalation of decreased concentrations of oxygen for 20 min from 11% to 8% oxygen balanced by nitrogen, followed by the inhalation of 8% oxygen and 92% nitrogen for 35 min as already described previously (Tskitishvili et al . 2014, 2016). All manipulations were performed at 37°C.…”

“…Our recent studies already showed that E4 has very good antioxidant, neuroprotective, neurogenic and angiogenic properties and the combined use of E4 with other steroids do not have any priority over the single use of E4 (Tskitishvili et al . 2014, 2016). …”