Type 1 Diabetes has confused doctors for centuries. Characterised by the auto-immune destruction of pancreatic beta cells, sudden and debilitating symptoms can arise without insulin treatment. Insulin is only one amongst three known hormones produced by the beta cell, leading researchers at Michigan State University (MSU) to examine one of these mysterious molecules, called C-peptide.
The life expectancy of a person with type-1 diabetes has increased significantly compared to pre-20th century, but unfortunately chronic complications still may develop, such as heart disease, nerve damage and retinopathy. However, there is evidence that short-term replacement of C-peptide could improve the progression of the disease, by enhancing the ability of red blood cells to affect blood flow. Using a 3D-printed fluidic device, Researchers at MSU tested the hypothesis that C-peptide combined with a charged form of zinc (Zn2+) would cause blood vessel dilation, by increasing the amounts of ATP, an energy-carrier molecule shown to stimulate the vessel dilator nitric oxide (NO).
The 3D-printed fluidic device provides an experimental model for investigating cellular communication in the pancreas. Red blood cells flowed in the albumin-containing buffer under INS-1 cells and ATP release was measured.
This platform allowed the researchers to examine the tissue-tissue communication between rat INS-1 cells (which can serve as a beta-cell mimic) and a blood vessel-like endothelium, a currently impossible task to achieve in vivo.
Initially it was thought that Zn2+ facilitated delivery of C-peptide to the red blood cells, but it was soon found the delivery was actually enhanced by Albumin, a peptide carrier in the bloodstream.
However, red blood cells incubated with C-peptide alone did not show a significant ATP increase – they found it is in fact a joint effort, where both zinc and C-peptide are delivered by albumin to the endothelium. This suggests that the next steps are to test zinc, C-peptide and albumin combinational treatment alongside insulin, and to identify the C-peptide receptor itself.
The full article is free to access until 3 July 2015 and can be found on the link below:
C-peptide and zinc delivery to erythrocytes requires the presence of albumin: implications in diabetes explored with a 3D-printed fluidic device
Yueli Liu, Chengpeng Chen, Suzanne Summers, Wathsala Medawala and Dana M. Spence
Integr. Biol., 2015,7, 534-543