Effects of Hypoxia on the Growth and Development of the Fetal Ovine Hepatocytes in Primary Culture

Abstract

Objective: To investigate the development and characterizations of the hepatocytes isolated from fetal ovine and to determine the effect of hypoxia on their growth and metabolism.

Methods: Fresh hepatocytes were isolated from the liver of fetal ovine at late gestation, cultured in specific media, and exposed to normoxia (21% O2) or hypoxia (2% O2). The cellular characteristics and population purity were identified by immunocytochemistry and flow cytometry (FCM). The effects of hypoxia on cell cycle and apoptosis of the hepatocytes were evaluated by FCM, whereas the cellular ultrastructure changes were examined with a transmission electron microscope.

Results: The cell purity of hepatocytes was over 95%. Under hypoxia exposure, the hepatocytes showed a gradual increase in proportion at the S phase and in proliferative index, followed with a compatible increase in apoptosis and progressively decreased cell viability. Additionally, the organelles of the hepatocytes demonstrated dramatic changes, including swelling of mitochondria, disorder in cristae arrangement, expansion of endoplasmic reticulum, and a large number of circular lipid droplets emerging in the cytoplasm.

Conclusion: Fetal ovine hepatocytes could be primarily cultured in a short-term culture system with a high purity of over 95% and with their preserved original characteristics. Hypoxia could induce changes in ultrastructural and inhibit the proliferation of cultured fetal ovine hepatocytes through apoptotic mechanisms.

Keywords: Cell cycle; Fetal ovine hepatocytes; Hepatocytes structure; Hypoxia; Primary culture.