HIF-1 regulates energy metabolism of Tibetan chicken brain during embryo development under hypoxia.

The Tibetan chickens (Gallus gallus; TBC) are an indigenous breed distributed in Qinghai-Tibet Plateau that are well adapted to a hypoxic environment. The energy metabolism of embryo brains in TBCs under hypoxia has been little reported. This study investigated changes in energy metabolism of TBCs brain during embryo development under hypoxia. We found TBCs exhibited a change of glycolysis and TCA cycle during embryo development under hypoxia. HIF-1 potentially involved this by directly inducing the overexpression of PDK1 and glycolytic genes, hexokinase(HK1) and lactate dehydrogenase A (LDHA) to increase glycolysis of TBCs to adapt hypoxia. Although these may not be unique to TBCs, as we had also found similar results in Dwarf Laying Chickens (DLCs), a lowland chicken breed, TBCs had stronger regulating ability. In summary, our study revealed HIF-1 induced energy metabolism change in TBCs brain via upregulating expressions of PDK1 and other HIF-1 target genes like HK1, LDHA to increase glycolysis for TBCs hypoxia adaptation during embryo development. It indicates the potential application of TBCs energy metabolism research for other animals living on the Qinghai-Tibet Plateau.