The Studies On Bcl-xl, Bax And Bid Expressions And Erythroblasts Apoptosis In Chronic Mountain Sickness

Objective In the plateau region, chronic mountain sickness (CMS) is very common,butthe study of its content is limited. Its pathogenesis is very complex,and it is notclarity nowadays.It is proved that Bcl-2family plays an important role in cellapoptosis, and in the apoptosis change,it is very important. This study is focus onthe expressions of Bcl-xl, Bax and Bid and the apoptosis of erythroblasts in patientswith chronic mountain sickness (CMS), discussing the effect of apoptosis and Bcl-2family in the process of CMS.Method The CMS was diagnosed on the basis of the consensus of “VI World Congresson Mountain Medicine and High Altitude Physiology”.In this study, The bone marrowspecimens of CMS group were collected from16patients with CMS, at the same time,the bone marrow specimens of Control group were collected from16patients withfracture of orthopedics. They were all males. The average ages of CMS group were43.40±14.90years old,and the average ages of Control group were43.37±10.07yearsold. The bone marrow mononuclear cells (BMMNCs) were separated for culture oferythroblasts. The apoptotic index (AI) of erythroblasts was measured by TUNELtechnique, the levels of Bcl-xl, Bax and Bid mRNA in erythroblasts of CMS patientsand controls were determined by RT-PCR. The differences were compared between CMS groupand Control group, and we should analyze the correlations among Bcl-xl, Bax, Bid,hemoglobin concentration (Hb) and AI.Results①The AI of erythroblasts in CMS group is (7.35±3.74)%,and the AI oferythroblasts in controls is （18.1±8.72)%, was lower than that in controls (P<0.01).②The Bcl-xl, Bax and Bid mRNA values were0.89±0.49,0.15±0.04and0.56±0.26,respectively, in CMS patients. The Bcl-xl, Bax and Bid mRNA values were0.46±0.32,0.50±0.09and1.32±0.27respectively in the controls．The expression of Bcl-xl mRNAin CMS patients was significantly higher than that in controls, and the expressions of Bax and Bid mRNA in controls patients were much higher than those in CMS,respectively (P<0.01).③In CMS patients, AI was negatively correlated with Bcl-xland positively correlated with Bid (r values were-0.524and0.575, respectively,P<0.05). However, the significant relationship was not found between the AI and BaxmRNA (P>0.05). Hb was positively correlated with Bcl-xl mRNA and negativelycorrelated with Bax and Bid mRNA (r values were0.628,-0.654and-0.659, respectively,P<0.05) in CMS patients. There was a negative correlation between AI and Hb (r valueswas-0.591, P<0.01) in CMS patients.Conclusions The results showed that apoptosis of erythroblasts is downregulated inCMS patients, the over-expression of Bcl-xl mRNA and low-expressions of Bax and BidmRNA might be involved in mechanism of the change of erythroblasts apoptosis in CMSpatients.