New Aspects of Central Nervous System Adaptation to Prenatal Hypoxia

Abstract

The aim of the investigation was to study the effect of chronic and acute prenatal hypoxia on the parameters of CNS functional activity and to assess the role of mitochondria in the protection of the CNS against experimental hypoxic influence in vivo. Materials and Methods. The experiments in vivo were performed on C57BL/6 mice. In order to model chronic prenatal hypoxia, pregnant female mice were placed daily into a hypobaric chamber beginning with the fourteenth day of gestation up to delivery. 280-300 mm Hg pressure corresponding to the altitude of 8000 m above sea level was maintained in the chamber for 2 h. Acute prenatal hypoxia was modeled on the eighteenth day of gestation. Pregnant females were placed for 4-5 min (till the first agonal breath) in the hypobaric chamber under 220-240 mm Hg pressure corresponding to the altitude of 10,000 m above sea level. Oxygen consumption rate by mice brain mitochondria was assessed on the first day of the post-natal period using a high-resolution Oxygraph-2k respirometer (Oroboros Instruments, Austria). To determine a general state of the CNS in the remote post-hypoxic period, a neurological status of the 4-week-old animals was evaluated according to the neurological deficit scale for small laboratory animals and Garcia's scale. Mnestic and cognitive abilities were also tested in Morris water maze. Results. Protocols of acute and chronic prenatal hypoxia modeling for mice have been designed. Acute hypoxic damage has been shown to result in the significant decrease of the basal oxygen consumption rate and intensity of oxidative phosphorylation by the brain

Prenatal Hypoxia Affects Foetal Cardiovascular Regulatory Mechanisms in a Sex- and Circadian-Dependent Manner: A Review

“…In contrast, in the adult offspring rats, an increased expression of Nfe2l2 , catalase and glutathione peroxidase was observed in the heart as a compensatory antioxidant response to prenatal hypoxia [ 92 ]. These results indicate that chronic prenatal hypoxia leads to the adaptation of the mitochondrial function in a duration-dependent manner [ 47 ].…”

The Role of Brain-Derived Neurotrophic Factor and Glial Cell Line-Derived Neurotrophic Factor in Chronic Fetal Oxygen Deprivation

“…These regulatory proteins participate actively in the formation and development of neuronal outgrowths, development of cerebral cortex, and in the processes of synaptic plasticity [ 2 , 3 ]. Neurotrophic factors play a crucial role in neuroprotection, promote the survival of nerve cells, prevent the development of apoptotic reactions in many neuronal populations, and, consequently, can influence pre- and postnatal brain development [ 4 , 5 ].…”