Dimethyl amiloride improves glucose homeostasis in mouse models of type 2 diabetes

SC Gunawardana, WS Head… - American Journal of …, 2008 - journals.physiology.org
SC Gunawardana, WS Head, DW Piston
American Journal of Physiology-Endocrinology and Metabolism, 2008journals.physiology.org
Dimethyl amiloride (DMA) enhances insulin secretion in the pancreatic β-cell. DMA also
enhances time-dependent potentiation (TDP) and enables TDP to occur in situations where
it is normally absent. As we have demonstrated before, these effects are mediated in part
through inhibition of neuronal nitric oxide synthase (nNOS), resulting in increased
availability of arginine. Thus both DMA and arginine have the potential to correct the
secretory defect in diabetes by enabling or enhancing TDP. In the current study we have …
Dimethyl amiloride (DMA) enhances insulin secretion in the pancreatic β-cell. DMA also enhances time-dependent potentiation (TDP) and enables TDP to occur in situations where it is normally absent. As we have demonstrated before, these effects are mediated in part through inhibition of neuronal nitric oxide synthase (nNOS), resulting in increased availability of arginine. Thus both DMA and arginine have the potential to correct the secretory defect in diabetes by enabling or enhancing TDP. In the current study we have demonstrated the ability of these agents to improve blood glucose homeostasis in three mouse models of type 2 diabetes. The pattern of TDP under different conditions indicates that inhibition of NOS is not the only mechanism through which DMA exerts its positive effects. Thus we also have explored another possible mechanism through which DMA enables/enhances TDP, via the activation of mitochondrial α-ketoglutarate dehydrogenase.
American Physiological Society