The Effects Of Emodin On Inhibiting Proliferation And Inducing Apoptosis In T Lymphocytic Leukemic Jurkat And Molt-4 Cells And The Possible Mechanisms

【Objective】To investigate the effects of Chinese traditional medicine Emodin on proliferation and apoptosis in T lymphocytic leukemic cell line Jurkat and Molt-4 and to explore the mechanisms of the effects by measuring the expression of proliferation and apoptosis related proteins as well as the expression of PI3K/AKT signaling pathway proteins.【Methods】Cell proliferation inhibition was detected by MTT assay. Cell apoptosis was measured by DNA ladder, Annexin V/PI double staining analysis, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling(TUNEL) assay and cell cycle analysis. The expressions of apoptosis related proteins, caspase family members and PI3K/AKT signaling pathway proteins were determined by Western Blot.【Results】(1) Emodin inhibited proliferation in Jurkat and Molt-4 cells, with the IC50 in 48h at 20.7μmol·L-1 and 25.1μmol·L-1, respectively. Cell apoptosis was observed with both time and dose dependent manner in Jurkat cells and also observed in Molt-4 cells by the detection of DNA fragments. (2) In Jurkat cells, the expressions c-myc, hTERT and Bcl-2 were explored to be down-regulated after the treatment of Emodin in a time dependent manner. Caspase-3, PARP were both activated, while the expressions of procaspase-8 and 9 both decreased. In Molt-4 cells, c-myc, bcl-2 were down-regulated and caspase-3, PARP were both activated after the treatment of Emodin. (3)Emodin have effects on PI3K/AKT signaling pathway in both Jurkat and Molt-4 cells, with the down-regulation of p-Akt,IκB-α,p-IκB-α, p-NF-κB,mTOR,p-mTOR,GSK-3β,p-GSK-3β,MAPK and p-MAPK in Jurkat cells and Akt,p-Akt,mTOR and p-mTOR in Molt-4 cells, while the expression of Akt and NF-κB showed no significant change and the expression of Bad in creased in Jurkat cells.【Conclusion】(1)Emodin could remarkbly inhibit proliferation and induce apoptosis in Jurkat and Molt-4 cells, and the down-regulation of bcl-2,c-myc,hTERT and caspase family members may have contributed to the apoptosis process.(2)PI-3K/Akt signaling pathway may have involved in the apoptosis of Jurkat and Molt-4 cells after treatment with Emodin.