What goes on as diabetic wounds heal?

US scientists have uncovered some of the molecular changes that occur during the healing of diabetic wounds, using ion mobility mass spectrometry to highlight the species involved. When diabetics suffer injuries to their lower legs or feet, they generally take longer to heal than for non-diabetics due to the physiological changes that disrupt the wound healing process. Now, John McLean from Vanderbilt University, and colleagues, have tried to find out which biomolecules at the wound site are responsible using ion mobility mass mass spectrometry.

Writing in Analytical Chemistry, they described how they collected fluid from wounds in diabetic and control mice using implanted sponges and compared the signals in the mass spectra. One prominent peak was present in the diabetic mice but absent from the control mice for up to 5 days after the sponges were inserted. It was assigned to S100-A8 using liquid chromatography-tandem mass spectrometry. This protein, also known as calgranulin A, regulates processes like cell stress, signal transduction and inflammation.

Using statistical analysis, two further peaks were identified that differentiated diabetic wound healing from control wound healing. They belonged to lysophosphatidylcholine, which is known to be involved in inflammation, and cholic acid, a bile acid that has been seen lately to be an important factor in diabetes.

The researchers suggested that "the methodology demonstrated in this study can be applied to the analysis of a variety of complex biological systems to rapidly identify biomolecular signatures of diseases and biological processes with IM-MS."