Study on pancreatic islet adaptation and gene expression during pregnancy in rats.
During pregnancy, the pancreatic islets undergo major structural and functional changes in response to increased peripheral resistance to insulin. In this study, we investigated the adaptive changes of the pancreatic islet beta-cell mass during pregnancy in rats, and explored profiles of islet gene expression at various stages of pregnancy. Some differentially expressed genes were verified by RT-PCR and Real-time PCR. Our results showed that compared with the non-pregnant control group, insulin synthesis, glucose-stimulated insulin secretion, islet beta-cell proliferation, and islet size were all increased in pregnant rats. The study also demonstrated that expression of several-hundred islet genes were changed during pregnancy, especially at day 14.5. The differentially expressed genes identified were distributed into eight main categories according to their biological functions: (1) genes involved in apoptosis or tumor; (2) genes related to binding; (3) genes involved in metabolism; (4) genes related to cell cycle; (5) genes for signal transducer activity; (6) genes related to structural molecule activity; (7) genes involved in transcription regulator activity; (8) genes for transporter activity. Among these genes, regenerating islet-derived 3 alpha (Reg3a) was remarkably increased during pregnancy. We hypothesize that differentially expressed genes may play an important role in adaptation of pancreatic islets during pregnancy in rats. In addition, the markedly increased expression of gene Reg3a is probably related to islet regeneration.
Department of Endocrinology, First Affiliated Hospital of Nanjing Medical University, 210029 Nanjing, China.
Ying
Y
Xue
Cuipin
C
Liu
Yu
Y
Xu
Qinxin
Q
Yuan
Kuanfeng
K
Xu
Xiaodong
X
Mao
Guofang
G
Chen
Xiaohong
X
Wu
Mathias D
MD
Brendel
Chao
C
Liu
D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D049109:Cell Proliferation; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D018149:Glucose Intolerance; D007328:Insulin / Q000097:blood / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000166:cytology* / Q000378:metabolism*; D037181:Lectins, C-Type / Q000235:genetics / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D000073718:Pancreatitis-Associated Proteins; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D046509:Tissue Culture Techniques; D015854:Up-Regulation
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D007328:Insulin; D037181:Lectins, C-Type; D000073718:Pancreatitis-Associated Proteins; C000612141:REG3A protein, human; D012333:RNA, Messenger; C000612146:Reg3a protein, rat