BLOOD MICROCIRCULATION IN MOUSE BLOOD MICROCIRCULATION IN MOUSE BRAIN WITH ALLOXAN DIABETES STUDIED BRAIN WITH ALLOXAN DIABETES STUDIED BY TEMPORAL LASER SPECKLE CONTRAST BY TEMPORAL LASER SPECKLE CONTRAST

IMAGINGIMAGING

Polina Timoshina (1,2), Rui Shi (2), Yang Zhang(2), Dun Zhu(2), ValeryTuchin (1,2,3), Qingming Luo(2)

1- Research-Educational Institute of Optics and Biophotonics, Saratov State University, Russia2- Britton Chance Center for Biomedical Photonics, Huazhong University of Science and Technology,

Wuhan, China3- Institute of Precision Mechanics and Control, Russian Academy of Sciences, Saratov, Russia

IntroductionIntroduction

The study of blood microcirculation is one of the most important problems of the medicineThis is caused by the fact that many diseases, such as cardio-vascular diseases, atherosclerosis, diabetes, chronic venous insufficiency cause functional and morphological changes of microcirculation of blood flowWe present the results of experimental study of changes of microcirculation of blood flow of brain in mice with diabetes by using Temporal Laser Speckle Contrast Imaging (TLSCI)Additionally a direct effect of glucose water solution (concentration 20% and 40%) on blood microcirculation was studied

Methods and materialsMethods and materials

Animal model:

In our research we used white laboratory mice weighing 20-30 g The animal model of aloxan induced diabetes was used 85 mg of alloxan was mixed with 2 ml of physiological saline Experimental diabetes in laboratory animals was provided by a single

subcutaneous injection of alloxan at a dose of 170 mg / kg body weight of the animal

In 10 days after injection of alloxan in experimental mice, analysis of glucose levels of blood using a glucometer was provided

The increase of blood glucose levels relative to a group of healthy mice was found

Methods and materialsMethods and materials

Optical method: We used temporal laser speckle contrast analysis that is based on temporal statistics, computing of speckle contrast images using a sequence of speckle images acquired along a few time points instead of using a spatial window

To conduct the study Huazhong University of Science and Technology (HUST, Wuhan, China) team has developed a special software, which allowed us in real time to assess changes of diameter of blood vessels and relative velocity of blood flow

Experimental setupExperimental setup

The measurements were carried out using a specially designed experimental setup: As a light source a He-Ne laser (632 nm) was used and a 12-bit CCD camera (pixel size ~ 6.45x6.45 m) combined with the microscope (Z16 APO, Leica, Germany working distance of 97 mm) was used to capture dynamic images with exposure time of 20 ms

Speckle images of internal organs: A) vessels of Speckle images of internal organs: A) vessels of healthy brain after skull trepanation, B) vessels healthy brain after skull trepanation, B) vessels of diabetic brain after skull trepanation of diabetic brain after skull trepanation

A B

Change of diameter of sagittal veins in brain: Change of diameter of sagittal veins in brain: 1-control group 1-control group 2- diabetic group 2- diabetic group

Change of relative values of velocity of Change of relative values of velocity of blood of sagittal vein: blood of sagittal vein: 1-control group1-control group2- diabetic group2- diabetic group

Speckle images of vessels in the brain under the influence of Speckle images of vessels in the brain under the influence of optical clearing agent: optical clearing agent: A) without influence, B) after application of 20% solution of A) without influence, B) after application of 20% solution of

glucose C) after application of 40% solution of glucoseglucose C) after application of 40% solution of glucose

a) b) c)

Change of relative values of diameter of Change of relative values of diameter of sagittal veinsagittal vein

ResultsResults

It was shown that in brain of diabetic group diameter of sagittal vein is increased and the speed of blood flow decreased relative to the control group

Topical application of 20%- and 40%- glucose increases diameter of blood vessels

Study of blood microcirculation disorders of brain at diabetes show that disease development in animals causes changes in the microcirculatory system

Acknowledgements

Saratov State UniversityDepartment of Optics and

Biophotonics

Saratov Fall Meeting 2014

We thank Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology (Wuhan, China) for support of these researches

This work was partially supported by RF Presidential grant 703.2014.2 “Scientific School Support” andGrant #13-02-91176 of Russian Foundation of Basis Research