Fibronectin and laminin promote differentiation of human mesenchymal stem cells into insulin producing cells through activating Akt and ERK.
BACKGROUND
Islet transplantation provides a promising cure for Type 1 diabetes; however it is limited by a shortage of pancreas donors. Bone marrow-derived multipotent mesenchymal stem cells (MSCs) offer renewable cells for generating insulin-producing cells (IPCs).


METHODS
We used a four-stage differentiation protocol, containing neuronal differentiation and IPC-conversion stages, and combined with pellet suspension culture to induce IPC differentiation.


RESULTS
Here, we report adding extracellular matrix proteins (ECM) such as fibronectin (FN) or laminin (LAM) enhances pancreatic differentiation with increases in insulin and Glut2 gene expressions, proinsulin and insulin protein levels, and insulin release in response to elevated glucose concentration. Adding FN or LAM induced activation of Akt and ERK. Blocking Akt or ERK by adding LY294002 (PI3K specific inhibitor), PD98059 (MEK specific inhibitor) or knocking down Akt or ERK failed to abrogate FN or LAM-induced enhancement of IPC differentiation. Only blocking both of Akt and ERK or knocking down Akt and ERK inhibited the enhancement of IPC differentiation by adding ECM.


CONCLUSIONS
These data prove IPC differentiation by MSCs can be modulated by adding ECM, and these stimulatory effects were mediated through activation of Akt and ERK pathways.
Lin
Hsiao-Yun
HY
Stem Cell Laboratory, Department of Medical Research and Education, Veterans General Hospital-Taipei, Taiwan.
Tsai
Chih-Chien
CC
Chen
Ling-Lan
LL
Chiou
Shih-Hwa
SH
Wang
Yng-Jiin
YJ
Hung
Shih-Chieh
SC
D015153:Blotting, Western; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D064987:Cell- and Tissue-Based Therapy / Q000379:methods*; D002867:Chromones; D003922:Diabetes Mellitus, Type 1 / Q000628:therapy*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D005353:Fibronectins / Q000378:metabolism / Q000494:pharmacology*; D005419:Flavonoids; D006801:Humans; D007150:Immunohistochemistry; D050417:Insulin-Secreting Cells / Q000166:cytology*; D007797:Laminin / Q000378:metabolism / Q000494:pharmacology*; D016086:Lentivirus; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects*; D009025:Morpholines; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors / Q000378:metabolism; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction
D002867:Chromones; D005353:Fibronectins; D005419:Flavonoids; D007797:Laminin; D009025:Morpholines; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; D051057:Proto-Oncogene Proteins c-akt; D048049:Extracellular Signal-Regulated MAP Kinases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one