Ca concentration and Ca/Mg ratio of erythrocytes in colectomised patients

In Hungary age standardized rates of incidence and mortality of colorectal cancers are prominently high, especially among males. Therefore treatment of cancer related disorders, like anemia also need remarkable attention. While colorectal tumor-related intestinal blood loss is one of the best known reasons of low hemoglobin content in blood, eryptosis should be also considered. To distinguish apoptosis of regular cells from programmed cell death of erythrocytes, the latter process being called eryptosis, we have to remember that erythrocytes have no nucleus, mitochondria, etc. It can be triggered by various factors, for example osmotic shock or oxidative stress and causes elevation in the Ca-content which is thought to be a key factor in the mechanism of red blood cell death. Generally, eryptosis helps to remove senescent red blood cells without intravascular hemolysis and inflammation, but perturbation in erythrocyte production and their programmed death can be reasons of anemia. Therefore we studied redox parameters and element concentrations of erythrocytes and the routine laboratory parameters of whole blood and the serum. The control group had no known cancerous processes (N = 11; age = 45 ± 15year) and the colorectal cancer-treated group had no known metastasis (N = 6; Stage = Dukes A-C; age = 65 ± 4year). Free sulfhydryl content was measured by Sedlak and Lindsay (1968) and H-donating ability was determined by Hatano et al. (1988). Erythrocyte element contents were measured with ICP OES, after digestion with nitric acid and hydrogen peroxide. Routine laboratory parameters were determined with ADVIA 2120 or ABX Micros 60 Analyser and with standard kits. Significance level was p < 0.01. In colorectal cancer treated patients, the hematocrit and hemoglobin content of blood was significantly lower than that of control the group. On the other hand, in this group Ca concentration and Ca/Mg ratio were remarkably elevated in erythrocytes. Their relatively high data indicates oxidative stress and that the lowered H-donating ability can underpin the research, although the latter parameters showed no significant differences between the two groups. These data support the idea that, in colorectal cancerous patients, the disturbed redox homeostasis and the elevated Ca-content may also have role in the progress of anemia.