[III-15-06] A role of Largen for hepatocellular proliferation and hypertrophy during pregnancy in mice
In humans, ectopic pregnancy that unusually occurred in the liver produced healthy babies in a few cases, suggesting a possibility that the liver has a similar function as the uterus to enable the maintenance of pregnancy. However, functional changes of the liver are not well known even in mice. We examined the changes in the liver during pregnancy and tried to identify the factors involved in the cellular changes of hepatocytes in mice. Female liver tissues were collected and weighed from D1 to D18 of pregnancy (D1 was defined as the day found vaginal plug after mating). The number and area of hepatocytes were determined using immunofluorescence (IF) and immunohistochemistry (IHC). In addition, the expression of proline-rich protein 16 called Largen (a regulator of cell size) was examined by q-PCR and IHC. The liver weight approximately doubled from D1 to D18 due to both proliferation and hypertrophy of hepatocytes. During late pregnancy, Largen was highly expressed in hepatocytes and placenta. We found that hepatocyte proliferation and hypertrophy occurred during pregnancy and Largen may be involved in pregnancy-related cellular changes in mice.