Spectral markers and morphological features of diabetic foot ulcer tissues

Abstract

Metabolic disorders are an integral part of the development of diabetes mellitus. One of the most severe complications of diabetes is a diabetic foot, which is characterized by the formation of necrotic sores. The aim of the study was to experimentally test the hypothesis of the formation and accumulation of β-structured protein aggregates in diabetic foot tissues as markers of diabetes associated disorders. The formation of β-structured protein aggregates promotes their non-enzymatic glycosylation, which in turn promotes aggregation. There is a positive connection between the individual links of the pathological process. Breaking this link is a prerequisite for effective treatment. The results of the optical image analysis indicate the presence of β-structured protein aggregates, confirmed by IR spectroscopy. Thus, the presence of the total β-conformation reaches 47,6%. The assumption of an increasing contribution from the β-antiparallel conformation was made. Clear IR markers of necrotic tissues in the absorption region of stretching vibrations of C=O and C–O molecular groups as well as a 2.5-fold increase in the intensity of the CH stretching bands compared to OH were observed. Conformational fitting and correlation analysis between different protein phases showed that the necrosis spectroscopic feature strongly correlates with water content, and α-helix plus triple helix negatively correlate with water content, β-conformation, and necrosis features. The assumption of an increasing contribution from β-antiparallel conformation connected with amyloid-like fibril formation was done.