Synergistic effect of high glucose and ANG II on proliferation of mouse embryonic stem cells: involvement of PKC and MAPKs as well as AT1 receptor.
This study examined the synergistic effect of high glucose levels and ANG II on proliferation and its related signal pathways using mouse embryonic stem (ES) cells. The combined use of a high glucose concentration (25 mM) and ANG II increased the level of [3H]thymidine/BrdU incorporation, and the number of cells compared with either treatment alone. Each treatment with high glucose or ANG II increased the cell population in the S phase compared with control, and the combined treatment of a high glucose concentration and ANG II significantly increased the number of cells in the S phase according to FACS analysis. Moreover, the high glucose-induced increase in [3H]thymidine incorporation was blocked by inhibiting the ANG II type 1 (AT1) receptor. The combined high glucose and ANG II significantly increased the STAT3 phosphorylation compared with high glucose or ANG II alone. ANG II stimulated the influx of Ca2+ in 25 mM glucose compared with 5 mM glucose. High glucose levels increase the level of PKC alpha, epsilon, and zeta translocation from the cytosol to the membrane fraction. In an examination of other signal pathways, the combined treatment significantly increased the level of p44/42, p38 MAPKs phosphorylation compared with either treatment alone. Indeed, the combined treatment increased the mRNA expression level of the protooncogenes and cell cycle regulatory proteins. In conclusion, the combined treatment of a high glucose concentration and ANG II had a synergistic effect in stimulating mouse ES cell proliferation through the Ca2+/PKC, MAPKs, and the AT1 receptor.
Kim
Yun Hee
YH
Department of Veterinary Physiology, BK21 Biotherapy Human Resources Center, College of Veterinary Medicine, Chonnam National University, Gwangju, Korea.
Han
Ho Jae
HJ
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D005947:Glucose / Q000008:administration & dosage* / Q000494:pharmacology; D007527:Isoenzymes / Q000378:metabolism; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D011493:Protein Kinase C / Q000378:metabolism*; D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000378:metabolism; D044140:Receptor, Angiotensin, Type 1 / Q000378:metabolism*; D016196:S Phase
D018797:Cell Cycle Proteins; D007527:Isoenzymes; D012333:RNA, Messenger; D044140:Receptor, Angiotensin, Type 1; D000804:Angiotensin II; D011493:Protein Kinase C; D020928:Mitogen-Activated Protein Kinases; D005947:Glucose; D002118:Calcium