Increased Insulin Secretion from Insulin-Secreting Cells by Construction of Mixed Multicellular Spheroids.
OBJECTIVE
We previously have shown that multicellular spheroids containing insulin-secreting cells are an effective therapy for diabetic mice. Here we attempted to increase insulin secretion by incorporating other cell types into spheroids.


METHODS
Multicellular spheroids of mouse MIN6 pancreatic β cells were formed in microwells alone and with aortic vascular endothelial MAEC cells or embryo fibroblast NIH3T3 cells. mRNA expression of insulin genes and insulin secretion of MIN6 cells in each spheroid were measured by real-time PCR and an insulin ELIZA kit. Moreover, collagen IV expression in each spheroid was analyzed by western blot.


RESULTS
In all cases, uniformly sized (about 300 μm) multicellular spheroids were obtained. MAEC or NIH3T3 cell incorporation into MIN6 spheroids significantly increased mRNA expression of insulin genes and insulin secretion. In addition, collagen IV expression, which was reported to enhance insulin secretion from pancreatic β cells, also increased in their spheroids.


CONCLUSIONS
The formation of mixed multicellular spheroids containing collagen IV-expressing cells can improve the insulin secretion from insulin-secreting MIN6 cells, and mixed multicellular spheroids can be a potent therapeutic option for patients with type I diabetes mellitus.
Department of Biopharmaceutics and Drug Metabolism Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.
Kosuke
K
Kusamori
Department of Biopharmaceutics and Drug Metabolism Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan. makiya@pharm.kyoto-u.ac.jp.|Institute for Innovative NanoBio Drug Discovery and Development Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan. makiya@pharm.kyoto-u.ac.jp.|Institute for Integrated Cell-Material Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan. makiya@pharm.kyoto-u.ac.jp.
Makiya
M
Nishikawa
Department of Biopharmaceutics and Drug Metabolism Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.
Narumi
N
Mizuno
Department of Biopharmaceutics and Drug Metabolism Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.
Tomoko
T
Nishikawa
Department of Biopharmaceutics and Drug Metabolism Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.
Akira
A
Masuzawa
Department of Biopharmaceutics and Drug Metabolism Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.
Yutaro
Y
Tanaka
Department of Biopharmaceutics and Drug Metabolism Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.
Yuya
Y
Mizukami
Institute for Innovative NanoBio Drug Discovery and Development Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.|Ritsumeikan-Global Innovation Research Organization, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan.
Kazunori
K
Shimizu
Institute for Innovative NanoBio Drug Discovery and Development Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.|Ritsumeikan-Global Innovation Research Organization, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan.|Department of Mechanical Engineering, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan.
Satoshi
S
Konishi
Department of Biopharmaceutics and Drug Metabolism Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.|Institute for Integrated Cell-Material Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.
Yuki
Y
Takahashi
Department of Biopharmaceutics and Drug Metabolism Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.|Institute for Innovative NanoBio Drug Discovery and Development Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, 606-8501, Japan.
Yoshinobu
Y
Takakura
D016475:3T3 Cells; D000818:Animals; D002478:Cells, Cultured; D024141:Collagen Type IV / Q000096:biosynthesis; D042783:Endothelial Cells / Q000378:metabolism; D005347:Fibroblasts; D007328:Insulin / Q000235:genetics / Q000378:metabolism*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D051379:Mice; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D018874:Spheroids, Cellular
D024141:Collagen Type IV; D007328:Insulin; D012333:RNA, Messenger
diabetes; extracellular matrix; insulin; spheroid; β cells