ABSTRACT
<p><b>OBJECTIVE</b>To cultivate human umbilical vein endothelial cells (HUVECs) in the serum of overfatigue rats with the intervention of Tongxinluo superfine powder (TXLSP). By examining the variation of the activity of JNK/c-Jun/HO-1 pathway, the possible mechanisms of vascular endothelial dysfunction under overfatigue conditions and the intervening effect of TXLSP were explored.</p><p><b>METHODS</b>The HUVECs were randomly divided into the normal control group, the model group, the SP600125 (a specific antagonist of JNK) group, the TXLSP group and the TXLSP + SP600125 group. The content of carboyhemoglobin (COHb) and the leak rate of lactic dehydrogenase (LDH) in different groups were measured. The mRNA and protein expression of JNK, c-Jun, HO-1 and the phosphorylation level of c-Jun (P-c-Jun) were detected using Western blot and PCR methods.</p><p><b>RESULTS</b>Compared with the normal control group, the COHb level in supernatant was increased significantly in the model group, and the expression of HO-1, JNK, c-Jun mRNA and corresponding proteins and P-c-Jun were also increased remarkably. The increases in these parameters were significantly decreased by SP600125. TXLSP showed remarkable up-regulation on the expression of JNK, c-Jun, P-c-Jun and HO-1 mRNA and their protein expression. Compared with the SP600125 group, the expressions of JNK, c-Jun, P-c-Jun and HO-1 mRNA and its protein in the TXLSP+SP600125 group were significantly increased at different time points (P<0.05, P<0.01).</p><p><b>CONCLUSIONS</b>The vascular endothelial dysfunction under overfatigue conditions is related to the activity of the JNK/c-Jun/HO-1 pathway. One of the mechanisms of TXLSP in improving the vascular endothelial function is to adjust the activity of the JNK/c-Jun/HO-1 pathway at gene and protein levels.</p>