Preliminary Study Of Inhibitory Effect Of Citral And Ara-c On Leukemia HL-60

Objective:Citral is the main component and effective monomer of chinese traditional medicine-listea fruit oil,with much bioactive function.and without genetic risk of long-term use.Recent studies have found that it could significantly inhibited many Leukemia cells,not only with strong targeting.but also no damage to normal cells. Ara-c is one of the most commonly used clinical drugs in the treatment of acute myeloid leukemia,but its clinical application was constrainted for the drawback that the cytotoxic enhances and reduce the sensitivity,with the increasing use of drugs. Therefore,there is a need to attract people to find a supplementary drug from natural products of plant origin,which both can reduce the toxicity of Ara-c,and enhance the sensitivity of leukemic cells to Ara-c. In this article we have researched the influence of Ara-C combined with citral on human acute promyelocytic leukemia cell HL-60, include on proliferation and apoptosis, cell membrane composition and function, cell microscopy and ultrastructural morphology, etc,to reveal Citral-Ara-c anti-HL-60 cells in the biological activity,to understand the effects type of Citral-Ara-c combined.Except that also evaluated the useage security of Citral-Ara-c from the perspective of human red blood cells to get theoretical basis in acute leukemia for future.Method:MTT assay was performed to detect the suppressing effect of different concentration of citral and Ara-c alone or in combination on HL-60 cells. Guinness formula was used to estimate synergistic effect of citral and Ara-c on HL-60 cells.DAPI staining was performed to observe nuclear morphology. dynamic micro-imaging analysis technique was employed to perform measurements on the membrane bending elastic modulus(Kc); the phase-analysis micro-electrophoresis laser scattering technique was used to measure the surface charges(Zeta potential); Atomic force microscopy(AFM) was used to watch membrane apparent micromorphological.Transmission electron microscopy(TEM) was performed to observe internal microstructure and the apoptosis body;Biochemical analysis of lipid raft composition; Spectrophotometry for Erythrocyte.Results:Citral and Ara-c alone or in combination could inhibit the proliferation of HL-60 cells in a dose dependent manner to some extent,fuether more they had synergistic effect.When cells was treated by drugs,many changes happened.,not only corraded the cell flexibility but also erased negetive charges on cell membrane showed by Zeta pulse analysis,even including chromatin condensation,nuclear shrinkage, cytoplasmic vacuolization and formation of apoptotic bodies. (Reflecting apoptosis was induced)The two drugs had no effect on the structure and fuction of red blood cells. Interference experiments on lipid rafts showed that proliferation activity of Citral is closely related to cholesterol levels maintaining.Conclusions:Citral could increase proliferation inhibition and apoptosis inducing activity of Ara-c. citral-Ara-C combined has no hemolysis on human erythrocytes.All of above is to say citral has a potential to enhance sensitivity and efficiency on Ara-C-treatment of leukemia.The mechanism of anti-HL-60 coused by citral-Ara-c combined involved the damage of membrane structure and function, the injury of mitochondria and other organelles in the cytoplasm,and the damage of nucleus and DNA.