CC BY
24B-I-15
OCT and laser speckle imaging for quantification of diffusivity and impact on blood flow of diabetic tissues and organs
D.K. Tuchina1234, P.A. Timoshina12, V.V. Tuchin1235
1Saratov State University, Astrakhanskaya str. 83, 410012 Saratov, Russia
2TomskState University, Lenin's av. 36, 634050 Tomsk, Russia
3Laboratory of Molecular Imaging, Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia 4Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilova str., Moscow 119991, Russia
5Institute of Precision Mechanics and Control RAS, Rabochaya str. 24, 410028 Saratov, Russia
Diabetes mellitus is a metabolic disease characterized by chronic hyperglycemia accompanied by the disruption of carbohydrate, lipid, and protein metabolism and development of long-term mi-crovascular, macrovascular, and neuropathic disorders, that can be successfully monitored by optical methods [1,2]. This paper presents the results of OCT and speckle imaging studies of tissue pathological transformation associated with protein glycation in animals with model alloxan-induced diabetes. The usage of optical clearing agents (OCAs) as probing molecules for monitoring of tissue diffusivity at protein glycation and blood flow dynamics in the pancreas of animals with induced diabetes have also been analyzed.
Diffuse reflection, total and collimated transmission of ex vivo tissues of rats of the control and diabetic groups were measured by UV-3600 spectrophotometer (Shimadzu, Japan) in a wide spectral range of 350-2500 nm. The difference in optical properties of tissues was observed. Investigation of optical and diffusion properties of diabetic skin in vivo was performed using OCT with the central wavelength of 930 nm and multichannel fiber-optic spectrometer USB4000-Vis-NIR (Ocean Optics, USA) in the spectral range of 500-900 nm during action of glycerol solutions. Glycerol diffusion in diabetic skin was obtained as significantly slower than in the control.
One of the promising techniques for quantification of blood microcirculation is laser speckle contrast imaging (LSCI). The observed in this study significant differences in the response of blood vessels to the action of an OCA in diabetic and control animals could be associated with the differences in the permeability of normal and glycated tissues. The permeability of glycated tissue could vary depending on its structure and composition, as well as on the shape and size of the OCA molecule.
References
[1] D. K. Tuchina and V. V. Tuchin, Optical and structural properties of biological tissues under diabetes mellitus, Journal of Biomedical Photonics & Engineering 4 (2) 020201-1-22 (2018).
[2] O. A. Smolyanskaya, E. N. Lazareva, S. S. Nalegaev, N. V. Petrov, K. I. Zaytsev, P. A. Timoshina, D. K. Tuchina, Ya. G. Toropova, O.V. Kornyushin, A.Yu. Babenko, J.-P. Guillet, V. V. Tuchin, Multimodal optical diagnostics of glycated biological tissues, Biochemistry (Moscow) 84, Suppl. 1, S124-S143 (2019).
