Information on the thesis

The aim of the dissertation was to research the features of antioxidant system, lipid
metabolism in blood and tissues of rats with experimental diabetes mellitus (EDM) under the
influence of vanadium and chromium citrates synthesized by nanotechnology method and to
develop new approaches to prevent the occurrence and correction of metabolic disorders in
diabetes.
To achieve this aim, three stages of experimental research were conducted. At the first
stage of the experimental part, we investigated the influence of vanadium citrate at the dose
of 0.125, 0.5 and 2.0 μg V/ml of water. At the second stage of the experimental research we
investigated the influence of chromium citrate at the dose of 0.1 and 0.2 μg Cr/ml of water.
And at the third stage of the experimental research we investigated the complex influence of
vanadium and chromium citrates at the dose of 0.5 μg V/ml and 0.1 μg Cr/ml water. The
body weight of male rats was 100-120 g. On the 31 st day of the study (the І, ІІ and ІІІ stages
of the experimental research), animals were induced with EDM by a single intraperitoneal
injection of 5% solution of alloxan monohydrate (“Synbios”, Ukraine) in the amount of 150
mg/kg of body weight of the animal (as solvent 0.9% NaCl). The animals were starving
during the last 24 hours. Control rats were injected intraperitoneally with 0.9% NaCl.
We investigated the effect of vanadium and chromium citrate on the blood glucose
concentration, insulin, the content of glycosylated hemoglobin, bodyweight and organs of
animals, the content of lipid peroxidation products, the activity of enzymes of antioxidant
defence system, the content of total lipids, and phospholipids in rats with EDM.
It was found that blood glucose concentration and the content of glycosylated
hemoglobin in the animals under EDM significantly increased, which indicated as result of
developed hyperglycemia. However, when exposed to vanadium and chromium citrate, both
separately and jointly, blood glucose concentration decreased. The normalizing effect was
observed with the use of vanadium citrate in the doses of 0.5 μg V/ml water and chromium
citrate in the doses of 0.1 μg Cr/ml water.
The antioxidant properties of vanadium and chromium compounds are entail the
normalization of the antioxidant system in the blood and tissues of rats with EDM. With the
combined action of vanadium and chromium citrates in animals with EDM, the content of
lipid hydroperoxides in the blood, skeletal muscle and pancreas and TBARS in the liver,
skeletal muscle and pancreas significantly decreased. In addition, superoxide dismutase
activity was increasing in the liver, skeletal muscles and pancreas and catalase activity was
increassing in the liver, but was decreasing in skeletal muscle. Glutathione peroxidase
activity was increasing in the liver and pancreas, but decreased in skeletal muscle and
kidneys. Glutathione reductase activity also increased in red blood cells, pancreas, but
decreased in the kidneys, while the content of reduced glutathione was increasing in all
research tissues in comparison to the parameters in animals with EDM.
We observed changes in separated links of lipid metabolism in rats with EDM. Rats
which were treated with vanadium citrate and chromium citrate improved their lipid
metabolism under EDM. Thus, the influence of vanadium citrate in three different doses
decreased the content of total lipids, phospholipids and esterified cholesterol in the blood of
diabetic rats. In the blood of rats with EDM the effect of chromium citrate at the dose of 0.1
μg Cr/ml of water significantly reduced the content of total lipids and phospholipids, and at
the dose of 0.2 μg Cr/ml of water the content of non-esterified and esterified cholesterol
compared to indicators in animals from the EDM. Due to the complex influence of vanadium
and chromium citrates, the contents of phospholipids, non-esterified cholesterol,
triacylglycerols decreased and the content of mono- and diacylglycerol increased compared to
parameters in animals with EDM.
We found that the compounds, which were synthesized by using nanotechnology, did
not have toxic effects and were well absorbed in the body of rats. For the first time, it has
been established that the combined use of vanadium citrate at the dose of 0.5 μg V/ml water
and chromium citrate at the dose of 0.1 μg Cr/ml water can be effective for the correction of
metabolic disorders, in particular hyperglycemia, dyslipidemia and oxidative stress that occur
under diabetes. The results of the studies suggest that the use of the appropriate
concentrations of these microelements may be an attractive therapeutic approach for the
prevention and treatment of diabetes.
Keywords: diabetes mellitus, hyperglycemia, vanadium citrate, chromium citrate,
alloxan, oxidative stress, antioxidant protection, lipids.