Objective        To observe the inhibitory effect of curcumol on Jurkat cells

and to explore the potential mechanism through JAK3 (Janus kinase 3)/STAT (signal transducers and activators of transcription) signal pathway.       Methods        Cell viability was assessed by tetrazolium single sodium salt

and the characteristics of curcumol-induced cell cycle arrest was detected by flow cytometry (FCM) after Jurkat cells exposed to di

fferent concentrations of curcumol (6.25

12.5

25 and 50 μg/mL) for 24 h. The cell morphology of apoptosis induced by curcumol was assessed by Hoechst 33258 staining. The Jurkat cells were divided into four groups including a normal control group

a interleukin-2 (IL-2) stimulation group

a JAK3 inhibitor group and a curcumol intervention group

and the protein expression levels of p-JAK3 (phosphorylated JAK3)

p-STAT3 and p-STAT5a were determined by Western blot analysis.       Results        After different concentrations of curcumol treatment

the Jurkat cell viability decreased significantly in a dose-dependent manner (P0.05). FCM results showed that apoptotic rate and the proportion of the cells arrested in S phase were elevated along with curcumol concentration increase

while the proportion of cells in G

2

/M phase declined gradually. After exposure to curcumol for 24 h

the Jurkat cells underwent typical apoptotic morphological changes

such as nucleus condensation and fragmentation. The expression levels of p-JAK3 and p-STAT5a in Jurkat cells were suppressed by 50 μg/mL of curcumol (P0.05

P0.01)

while there was no obvious change in STAT3 expression (P0.05).       Conclusion        The underlying mechanism of curcumol on suppressing the proliferation of Jurkat cells may be associated with S to G

2

/M phase arresting and JAK3/STAT5 pathway down-regulation.