Biochemical and Biophysical Research Communications
Level of sialic acid residues in platelet proteins in diabetes, aging, and Hodgkin's lymphoma: a potential role of free radicals in desialylation
Section snippets
Materials and methods
Selection of cases. (a) Old age: Twenty male volunteers, age above 60 years and without any ill health, were included to see the effect of aging on the selected parameters.
(b) Diabetes: Twenty type 2 diabetic subjects (male, aged between 30 and 40 years) who were diagnosed first time as diabetic with severe derangement of glucose homeostasis for last 6 weeks (HbA1c level >10%) were included in the study. They were free from any diabetic complications and other major ill health.
(c) Malignancy:
Results
The level of sialic acid residues and carbonyl content of platelet proteins in control, diabetics, malignant cases, and in old age are shown in the Table 1. The levels of sialic acid residues in platelets were found to be significantly (p<0.05) decreased in diabetics, Hodgkin's lymphoma cases, and old age, whereas carbonyl contents of platelet proteins were significantly (p<0.05) increased in these cases in comparison to control subjects. The correlation coefficients (rs) between levels of
Discussion
The present study revealed that oxidant injury/free radical reaction can cause desialylation and carbonylation of platelet proteins in in vitro condition. The elevated level of carbonyl content, the decreased sialic acids in platelets, and the negative correlation between sialic acid content and carbonylation in diabetes, malignancy, and aging reflects the fact that free radical reaction might be causing desialylation of platelet glycoproteins in these in vivo clinical conditions associated
Acknowledgements
The authors are indebted to late Prof. Rajshankar, IMS, Banaras Hindu University, Varanasi, India, Prof. S.K. Sen, Head of Biochemistry, JIPMER, Pondicherry, and Dr. Zachariah Bobby, Asst. Prof. of Biochemistry, JIPMER for their keen interest and valuable help during the course of study. The part of the work was carried out in IMS, BHU, Varanasi when Dr. Kalyan Goswami was working there.
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