Cellular and Molecular Life Sciences

, Volume 69, Issue 8, pp 1289–1304 | Cite as

The role of mammalian target of rapamycin (mTOR) in the regulation of pancreatic β-cell mass: implications in the development of type-2 diabetes

Review

Abstract

Type-2 diabetes mellitus (T2DM) is a disorder that is characterized by high blood glucose concentration in the context of insulin resistance and/or relative insulin deficiency. It causes metabolic changes that lead to the damage and functional impairment of organs and tissues resulting in increased morbidity and mortality. It is this form of diabetes whose prevalence is increasing at an alarming rate due to the ‘obesity epidemic’, as obesity is a key risk factor in the development of insulin resistance. However, the majority of individuals who have insulin resistance do not develop diabetes due to a compensatory increase in insulin secretion in response to an increase in insulin demand. This adaptive response is sustained by an increase in both β-cell function and mass. Importantly, there is increasing evidence that the Serine/Threonine kinase mammalian target of rapamycin (mTOR) plays a key role in the regulation of β-cell mass and therefore likely plays a critical role in β-cell adaptation. Therefore, the primary focus of this review is to summarize our current understanding of the role of mTOR in stimulating pancreatic β-cell mass and thus, in the prevention of type-2 diabetes.

Keywords

Type 2 diabetes Obesity β-cell mass mTOR TSC Rheb S6K PKB AMPK RICTOR 

Notes

Acknowledgments

J.X. was supported by a CONACYT studentship awarded by the Mexican government (Scholarship No. 206710). T.P.H. was supported by a Welcome Trust project grant (WT081268MA). We thank Dr. Edith Gomez for a critical reading of this manuscript.

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© Springer Basel AG 2011

Authors and Affiliations

  1. 1.Department of Cell Physiology and PharmacologyUniversity of LeicesterLeicesterUK

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