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Objective: To investigate the effects and molecular mechanisms of 2-12alkyl-6-methoxycyclohexa-2,5-diene-1,4-dione(DMDD) on diffuse large B lymphoma (DLBCL)., Methods: In animal experiments, 4-week-aged BALB/C mice were divided into 5 groups, 20 mice in each group. Mice were inguinal injected with DLBCL cell line OCI-LY19 cells 0.1 ml at the concention of 1 × 10 7 /ml. Two days later, mice were treated with DMDD at the doses of 0, 1, 5, 25 and 125 mg/kg by intragastric administration respectively, once /2 days. Ten mice of each group were killed on the 18th day of administration, and the tumor tissues were weighed. The survival time of the remaining mice were recorded. In cell experiments, OCI-LY19 cells were added to 96-well culture plates, 100 μl 1×10 5 cells/ml per well, then 100 μl DMDD was added to the well and the final concentrations were 0, 1, 5, 25 and 125 μmol/L respectively. The cells were treated with DMDD for 0, 24, 48 and 72 h, three wells in each group. The cell proliferation activity was detected by MTS assay. According to the results of cell proliferation experiments, OCI-LY19 cells were treated with DMDD at the concentrations of 0 μmol/L, 5 μmol/L and 25 μmol/L for 24 h. The apoptosis rate was analyzed by flow cytometry, the nuclear type was observed by hoechst staining, the mitochondrial membrane potential was observed by JC-1 staining, cytotoxicity of drugs was evaluated by LDH release experiment, gene expression and transcription were analyzed by qPCR and Western blot., Results: Compared with 0 mg/kg drug group, DMDD at the dose of 1～125 mg/kg could inhibit the growth of tumor tissue in mice and prolong their survival time (P＜0.01). Cell experiments showed: in DMDD group, the proliferation activity of OCI-LY19 cells was decreased significantly and the level of apoptosis was increased significantly (P＜0.01), nuclear fragmentation, agglutination, apoptotic bodies occurred and mitochondrial membrane potential was decreased, the LDH release rate was increased significantly (P＜0.01), the expressions of caspase-3 and bax genes and the phosphorylation level of Ikappa B alpha in cells were up-regulated significantly, the protein expression levels of bcl-2, bcl-xL, jak2 and stat3 were inhibited significantly (P＜0.01)., Conclusion: DMDD can inhibit the expressions of JAK2, STAT3 and p-Ikappa B alpha in JAK2/STAT3 and NF-kappa B signal pathways, down-regulate BCL-2/BAX and activate Caspase-3, finally, activate the endogenous pathway of mitochondrial apoptosis in OCI-LY19 cells and promote the apoptosis of DLBCL cells, inhibit proliferation of OCI-LY19 cells. It has inhibitive effects on DLBCL.

This study was aimed to investigate the effect of D-limonene on K562 leukemia cells and its mechanism. Inhibitory effect of D-limonene on proliferation of K562 leukemia cells was assayed by MTT method and cell apoptosis was detected by flow cytometry and DNA agarose gel electrophoresis, the morphologic change of K562 cells was observed by microscopy. The results showed that when K562 cells were treated with 0.125 - 1.0 mmol/L of D-limonene for 48 hours, the proliferation of K562 cells was obviously inhibited in dose-dependent manner. Typical morphological changes and the typical DNA ladder on agarose gel electrophoresis for analysis of cellular apoptosis were significantly appeared in D-limonene treated K562 cells. Simultaneously, the sub-G1 peak was found in FCM analysis. It is concluded that the D-limonene can inhibit proliferation of K562 cells in dose-dependent manner, cause cell detained at G1 phase and induce apoptosis of K562 cells.

Aim: To investigate the effects and permeation mechanism of D-limonene and L-limonene on transdermal delivery of ligustrazine hydrochloride (LH)., Methods: Transdermal flux of LH through porcine skin was determined in vitro by Franz-type diffusion cells. The peak shift and peak areas of C-H stretching vibration absorption were estimated by Fourier transform-infrared (FTIR). Morphological changes in the stratum corneum (SC) treated with enhancers were observed by a scanning electron microscope (SEM) and apparent density, a new concept, was proposed to estimate the desquamated extent of SC for the first time., Results: There were no statistic difference (P > 0.05) between the transdermal fluxs of the enantiomer enhancers which were higher than those of control and azone. But the lag time of L-limonene was 2.55 times than that of D-limonene. The FTIR results revealed that the shift and decreased peak area of C-H stretching vibrations in the SC lipids were dependent on the enhancers. The enantiomers permeation enhancers, D-limonene and L-limonene, were able to perturb and extract the SC lipids to different extent. The disordering and extracting lipids activity of L-limonene was stronger than that of D-limonene. SEM studies demonstrated that the extraction of lipids was depended on the selected penetration promoters., Conclusion: D-limonene was the most effective enhancer which had the greater transdermal flux of LH and the least lag time. The results showed that the permeation enhancement mechanism of the enantiomer enhancers to LH was multiple ones including disordering and extracting the SC lipids and probably including stereoselective mechanism.

To investigate the effects of D-limonene (D-L) on the cell growth and apoptosis in HL-60, K562 cells and to elucidate its mechanism, the influence of D-L on proliferation of HL-60 and K562 cells was determined by propidium iodide assay, the expression levels of mutant p53, bcl-2, bax gene were detected by cell morphological analysis, flow cytometry and immunohistochemistry staining, the D-L-inducing HL-60 and K562 cell apoptosis in vitro was observed systematically. The results showed that D-L inhibited HL-60 and K562 cell growth in a dose- and time-dependent manner with the IC50 of 0.75 mmol/L similarly, D-L induced apoptosis of HL-60 and K562 cells, and expression of bcl-2 gene was down regulated by D-L in a concentration-dependent manner in HL-60 cells. The bcl-2, mutant type of p53 genes were down regulated while bax gene was up regulated by D-L in a concentration-dependent manner in K562 cells. It is concluded that D-L can inhibit proliferation and induce apoptosis of HL-60 and K562 cells. The bcl-2, mutant type of p53 and bax may be involved in the gene regulation of D-L-induced apoptosis.