The Studies On Bcl-2,Bcl-xl,Bax And Bid Expressions In Bone Marrow Mononuclear Cells Of Chronic Mountain Sickness

Objective Chronic mountain sickness(CMS) is a common disease in plateau area. The excessive accumulation of red blood cells is one of the main characteristics of CMS, but its mechanism has not been fully elucidated. Apoptosis plays an important role in hematopoietic regulation in physiological conditions. Our previous studies have found that hematopoietic cell apoptosis was downregulated in CMS. The aim of this study was to research the changes of Bcl-2, Bcl-xl, Bax and Bid proteins in bone-marrow mononuclear cells(BMMNCs), and the relationships between them and serum EPO etc. in CMS, and to explore the role of Bcl-2 families on excessive accumulation of red blood cells in CMS.Methods 20 male CMS patients(CMS group) were diagnosed by “Consensus statement on chronic and subacute high altitude diseases” in “VI World Congress on Mountain Medicine and High Altitude Physiology”(2004, Qinghai, Chnia). They were Chinese Hans with 49.45±9.94 years old of average age; 20 male healthy adults as the control group, they were also Chinese Hans with 47.9±12.84 years old of average age. Bcl-2, Bcl-xl, Bax and Bid protein levels in BMMNCs were detected by Western blot. The serum EPO level was determined by ELISA. The relationships among Bcl-2, Bcl-xl, Bax, Bid, EPO and major clinical or experimental data of CMS were analyzed.Results 1. The BMMNCs Bid protein expression of CMS patients was higher than it of control group(0.59±0.40 vs. 0.36±0.27, P=0.037). 2. The Bcl-2 protein expression levels of BMMNCs was not significantly different between two groups([0.0097(0.00,0.45) vs. 0.0514(0.00,0.51)], Z=-0.56,P=0.57). 3. BMMNCs Bax protein expression level was 0.78±0.50 in CMS group and was 0.73±0.50 in the control group. There was no significant difference between these two groups(P=0.75). 4. The Bcl-xl protein expression was not detected in CMS patients and control group. 5. The serum EPO level of CMS group was obviously higher than that of control group [(269.28±127.77)pg/ml vs.(131.31±67.65)pg/ml], P=0.004]. 6. There was no obvious relationship between Hb, EPO and Bcl-2, Bax, Bid protein in CMS patients(P>0.05).Conclusions In CMS BMMNCs, the expression of Bid protein of Bcl-2 family proteins was higher, while the Bcl-2, Bax protein levels were no significnat change, and Bcl-xl protein was not detected. No relationship was found between them and Hb. There is a higher level of serum EPO level in CMS patients than the same altitude healthy people. These results indicated that there is some degree of disturbance in Bcl-2 families proteins in CMS hematopoietic cells. But the mechanism of excessive accumulate of red blood cells and hematopoietic cells apoptosis in CMS are need to further study.