Abstract:

Objective  To explore whether the spleen can affect the increase of isletβ cell mass in pregnant mice. Methods  40 female KM mice, aged7 weeks, were divided into four groups: the splenectomized pregnant group, the sham pregnant group, the splenectomized control group and the sham control group without pregnancy. Fasting bloodglucose was measured in different study periods. After parturition, the pancreas tissue was obtained from various groups of mice and immunohistochemically stained for  β cell mass measurement using an image analysis system. Islet and spleen cells isolated from mice were purified and co-cultured in Transwell. The proliferation of islet cells was measured following CCK-8treatment by an enzyme-labeling instrument at 490?nm. Results  There was a significant increase of islet β cell mass in the sham pregnant group compared with that in the sham control group（11.89mg±2.83mg vs 7.03mg±2.71mg, P＜0.05）. However, the islet β cell mass in the splenectomized pregnant group was only 6.10mg±2.12mg,which was significantly lower than that in the sham pregnant group(P＜0.05). In the splenectomized pregnant group and the sham pregnant group, fasting blood glucose concentration was normal. In vitro cell co-culture showed that spleen cells promotedthe proliferation of islet β cells. Conclusion  Spleen cells canpromote the increase of islet cell mass by secreting some factors; splenectomy may prevent the increase of islet cell mass in pregnant mice.

Key words: Splenectomy; Islet βcell mass; Pregnant Mice; Coculture