Comparative study of biochemical and morphological parameters in rats with Walker 256 and Walker 256/DOX carcinosarcoma.

AIM: To evaluate the changes of some biochemical blood plasma parameters and morphological structure of the internal organs of rats with transplanted doxorubicin (DOX)-sensitive (Walker 256) and doxorubicin-resistant (Walker 256/DOX) strains of Walker 256 carcinosarcoma. MATERIALS AND METHODS: The study was performed on female Wistar rats with transplanted Walker 256 or Walker 256/DOX and intact animals (control). On the 9th day after transplantation of tumor cells, a comparative analysis of some blood plasma biochemical parameters and morphological examination of the liver, kidneys, myocardium and spleen of rats was carried out. RESULTS: Walker 256 growth, in comparison with Walker 256/DOX, is accompanied by more pronounced systemic effect on tumor-bearing rats. Uric acid concentration in the blood plasma of Walker 256 bearing rats was significantly (by 15.5%) higher than in Walker 256/DOX bearing rats. Aspartate aminotransferase activity in the Walker 256 group was significantly (by 107.2%) higher than in Walker 256/DOX group, but alanine aminotransferase activity was 58.5% lower. 56.7% decrease of alkaline phosphatase in rats with Walker 256, and 21% increase of this index in rats with Walker 256/DOX were observed. The growth of Walker 256 carcinosarcoma led to greater structural damage of the liver, kidneys and spleen in experimental animals compared with Walker 256/DOX strain. CONCLUSION: Tumor growth in rats with Walker 256/DOX leads to less pronounced changes in the biochemical parameters of rat blood plasma and morphological structure of internal organs compared with wild-type carcinosarcoma.

Structural changes of serum albumin in response to oxidative stress caused by Walker-256 carcinosarcoma growth.

AIM: To assess oxidative stress and structural changes of the serum albumin in rats with transplanted Walker-256 carcinosarcoma (W256) strains with varying sensitivity to doxorubicin (Dox). MATERIALS AND METHODS: The study was performed on female Wistar rats with transplanted W256. On the 9th day after tumor cell transplantation an analysis of peripheral blood, oxidative stress parameters, and structural changes of serum albumin of experimental animals was performed. RESULTS: On the 9th day after W256 transplantation a significant increase in the leukocyte counts was observed in the groups of animals with the Dox-resistant and parental (Dox-sensitive) W256 tumors compared with the group of the intact animals: up to 14.24 ± 1.92 â€¢ 103/µl and 9.78 ± 1.03 â€¢ 103/µl, vs 8.92 ± 1.04 â€¢ 103/µl, respectively, due to the increase of granulocyte and monocyte counts. The number of lymphocytes was within the normal range. The level of hemoglobin and the erythrocyte counts were also within normal limits, but hematocrit in both groups of animals with tumors somewhat increased against the background of 1.2-fold elevation of the mean erythrocyte volume. In the group of rats with Dox-resistant W256, there was observed a decrease in the plateletcrit by almost 22% and thrombocyte counts - by 28%. Analysis of oxidative stress indices revealed a significant increase in the level of reactive oxygen species, 2-fold increase of malonic dialdehyde level and the degree of oxidative damage of blood plasma proteins, as well as a decrease in the activity of catalase in hemolysates (by 12-15%) in both groups of tumor-bearing rats. With the use of differential scanning calorimetry, UV and fluorescence spectroscopy we have revealed anomalous conformational changes of albumin caused by tumor development: structural rearrangements in the region of its first drug binding site located in the IIA domain, separation of globular parts of albumin molecule, and partial "opening" in a protein molecular three-domain structure resulting a loss of its thermal resistance. CONCLUSION: The development of transplanted Walker-256 carcinosarcoma, especially its Dox-resistant variant, results in severe metabolic intoxication reflected in alteration of hematological parameters, and indices of oxidative stress, as well as architectonic changes of serum albumin.