Effect of 350 kDa Glycoprotein in Royal Jelly on Primary Culture of Rat Hepatocytes

Abstract

The functions of the 350 kDa glycoprotein in royal jelly (RJ) on the primary monolayer culture of rat hepatocytes were examined. In the serum-free L-15 medium supplemented with the RJ protein, the monolayer culture of hepatocytes was maintained for 20 days. In contrast, without the RJ glycoprotein, the number of the hepatocytes which adhered to the dish decreased to less than one-half the number of inoculated cells during 20 days of culture. The amount of albumin secreted in the medium was monitored as an expression of liver-specific function. In the medium with the RJ glycoprotein, the hepatocytes maintained the secretion of albumin at a similar high level for 2 days compared to that in the starting culture, followed by diminishment to a low level. In contrast, the secretion of albumin by the hepatocytes cultured without RJ glycoprotein was decreased rapidly with time. As a control experiment, bovine serum albumin added to the medium did not show any effect both on the maintenance or albumin synthesis of rat hepatocytes.