MicroRNA-7 regulates the mTOR pathway and proliferation in adult pancreatic β-cells

Y Wang, J Liu, C Liu, A Naji, DA Stoffers - Diabetes, 2013 - Am Diabetes Assoc
Y Wang, J Liu, C Liu, A Naji, DA Stoffers
Diabetes, 2013Am Diabetes Assoc
Elucidating the mechanism underlying the poor proliferative capacity of adult pancreatic β-
cells is critical to regenerative therapeutic approaches for diabetes. Here, we show that the
microRNA (miR)-7/7ab family member miR-7a is enriched in mouse adult pancreatic islets
compared with miR-7b. Remarkably, miR-7a targets five components of the mTOR signaling
pathway. Further, inhibition of miR-7a activates mTOR signaling and promotes adult β-cell
replication in mouse primary islets, which can be reversed by the treatment with a well …
Elucidating the mechanism underlying the poor proliferative capacity of adult pancreatic β-cells is critical to regenerative therapeutic approaches for diabetes. Here, we show that the microRNA (miR)-7/7ab family member miR-7a is enriched in mouse adult pancreatic islets compared with miR-7b. Remarkably, miR-7a targets five components of the mTOR signaling pathway. Further, inhibition of miR-7a activates mTOR signaling and promotes adult β-cell replication in mouse primary islets, which can be reversed by the treatment with a well-known mTOR inhibitor, rapamycin. These data suggest that miR-7 acts as a brake on adult β-cell proliferation. Most importantly, this miR-7–mTOR proliferation axis is conserved in primary human β-cells, implicating miR-7 as a therapeutic target for diabetes.
Am Diabetes Assoc