Dihydroartemisinin and its anticancer activity against endometrial carcinoma and cervical cancer: involvement of apoptosis, autophagy and transferrin receptor

INTRODUCTION@#Dihydroartemisinin (DHA) is a first-line antimalarial drug with relatively low toxicity. DHA has been speculated to possess a broad-spectrum antitumour effect. However, the potential value of DHA for the treatment of endometrial carcinoma or cervical cancer is unclear.@*METHODS@#We used human endometrial cancer cells and cervical cancer cells to assess whether DHA alone or when combined with cisplatin would induce cell death. We aimed to elucidate the role of autophagy in DHA-induced cytotoxicity in both endometrial and cervical cancer cells, and explore the impact of DHA treatment on cell proliferation, apoptosis and autophagy.@*RESULTS@#DHA alone or in combination with cisplatin induced cell death in a dose- and time-dependent manner. Caspase-3 mRNA and cleaved caspase-3 protein levels were markedly elevated following DHA treatment either in the presence or absence of cisplatin, suggesting a role of apoptosis in DHA-induced cell death. DHA treatment activated the autophagic pathway, as evidenced by increased monodansylcadaverine-positive staining, elevated microtubule-associated protein 1 light chain 3 (LC3)-II/LC3-I ratio, and enhanced p62/sequestosome 1 degradation. Inhibition of autophagy by 3-methyladenine further enhanced the cytotoxicity of DHA towards tumour cells. mRNA levels of transferrin receptor (TfR) were suppressed upon DHA treatment and knockdown of TfR by RNA interference caused further DHA induction of cancer cell death.@*CONCLUSION@#Our results suggest a clinical value for DHA in the treatment of endometrial carcinoma and cervical cancer. Our data revealed possible anticancer mechanisms of DHA that involve regulating apoptosis, autophagy pathway and levels of TfR.

Effect of Arsenic Trioxide Combined with Dihydroartemisinin on THP-1 Cells Proliferation and Apoptosis / 中国实验方剂学杂志

Objective:To investigate the effects of arsenic trioxide combined with dihydroartemisinin on proliferation, cell cycle, and apoptosis of THP-1 cells, and explore the mechanism. Method:The thiazolyl blue （MTT） method was applied to detect the effect of different concentrations of arsenic trioxide, dihydroartemisinin and arsenic trioxide combined with dihydroartemisinin on the proliferation of THP-1 cells. Annexin V/propidium iodide（PI）assay was used to detect the change of THP-1 cell cycle and apoptosis．Western blot was performed to assess the expression of cysteine protease-3（Caspase-3）, cleaved Caspase-3, B-lymphocytoma-2（Bcl-2） and Bcl-2 associated X protein （Bax）. The changes of cell morphology were observed under high intension microscope. Result:Compared with blank group, arsenic trioxide and dihydroartemisinin both exhibited obvious antiproliferative effect on the human acute monocytic leukemia cell line THP-1 in time-dose dependence （P<0.01）. After 48 h, compared with the same dose of arsenic trioxide or that of dihydroartemisinin alone, the inhibition effect of 1 µmol·L-1 arsenic trioxide combined with 2 µmol·L-1 dihydroartemisinin on proliferation of THP-1 cells was significantly stronger （P<0.01）. Compared with the control group, arsenic trioxide combined with dihydroartemisinin significantly arrested the cells in G1 phase （P<0.01）, induced the downregulation of Caspase-3 and Bcl-2 （P<0.01） and upregulation of cleaved Caspase-3 significantly（P<0.05）. Conclusion:Arsenic trioxide combined with dihydroartemisinin can significantly inhibit the proliferation and induce apoptosis of THP-1 cells. The possible mechanism may be related to arrest the cells in G1 phase, reduce the expression of Caspase-3 and Bcl-2, increase the expression of cleaved Caspase-3.

Effect of dihydroartemisinin on permeability of human erythrocyte membrane infected plasmodium / 中国中药杂志

In view of the fact that the antimalarial effects of artemisinins are significant but the mechanism has not yet been clarified and there are many different opinions, it is possible that artemisinins can produce high anti-malarial efficacy through various mechanisms and multiple pathways. In addition, the researches on the pathogenesis of malaria "erythrocyte membrane plasmodial surface anion channel (PSAC)" in the past few years have provided more positive findings, which may confirm and discover the new antimalarial mechanism of artemisinins. This paper was as to study the effect of dihydroartemisinin (DHA) in vitro on erythrocyte membrane permeability of HB3 plasmodium infection, with using the mechanism of 5% sorbitol can be used to kill the Plasmodium falciparum in red blood cell membrane selectively, the effectual difference of sorbitol on the killing of P. falciparum with adding DHA or not was detected, so as to investigate whether DHA can affect the permeability of the erythrocyte membrane. Result showed that, Pre-stimulation with 10 nmol·L⁻¹ DHA (the final concentration of plasmodium in vitro culture system) for 30 min could significantly decrease the killing effect of sorbitol on the HB3 plasmodium in the P. falciparum erythrocytic cycle, and DHA may inhibit the permeability of the erythrocyte membrane for preventing sorbitol through the red blood cell membrane, thereby reducing the killing effect of sorbitol on the P. falciparum.

Therapeutic effect of DHA on lupus nephritis and its relationship with SIGIRR inducing immune negative regulation / 中国免疫学杂志

Objective:To inspect the relationship between the therapeutic effect of DHA on lupus nephritis and the negative immune regulation of TLR4/NF-κB signal pathway which was induced by SIGIRR;in vitro,to observe the effect of DHA on damaged HK-2 cell.Methods: In vivo,MRL/lpr mice were divided in model group,DHA groups(25,50,100 mg/kg),positive group (prednisone,5 mg/kg),and C57BL/6 mice were taken as control group.Administrate drugs daily for 12 weeks.Examine the changes in renal pathology;the expression of SIGIRR,IRAK1,TRAF6 in kidneys were determined by Western blot.In vitro,treat human renal tubular epithelial cell HK-2 cells with LPS ,and co-culture cells with DHA at the concentration of 0.67 μg/ml to 6.00 μg/ml for 6 h, 12 h and 24 h.Detect SIGIRR expression by Western blot and the level of IL-6 and CCL2 of HK-2 cells by ELISA.Results:In vivo, renal pathology revealed that kidneys of model group were damaged , while treatment with 100 mg/kg DHA alleviated renal injury.Compared to model group ,SIGIRR expression of DHA 100 mg/kg group increased a little ,and the expression of this protein had a tendency to increase with the augment of DHA dose .In vitro,DHA treatment reduced secretion of CCL 2 in HK-2 cells,and treatment of 0.67 μg/ml DHA for 24 h increased SIGIRR expression significantly , which also showed a growing expression with time.Conclusion:DHA could inhibit development of mouse lupus nephritis through increasing SIGIRR expression which inhibited TLR4/NF-κB signal pathway;DHA inhibited CCL2 secretion of HK-2 cells which were irritated by LPS ,and it may be associated with increased expression of SIGIRR .

The evaluation of coated granules to mask the bitter taste of dihydroartemisinin / A avaliação de grânulos revestidos para mascarar o sabor amargo da diidroartemisina

The purpose of this study was to mask the bitter taste imparted by dihydroartemisinin (DHA) by the use of different coating materials. Trial-1 and trial-2 were conducted to prepare the DHA granules. The granules produced from trial-1 were irregular in shape and smaller in size while the trial-2 granules were more regular and larger in size. The granules obtained from both trials were then coated with two different coating methods, namely A and B, depending upon coating material. The trial-2 granules showed better flow properties than trial-1 granules. In vitro dissolution studies in phosphate buffer at pH 6.8 revealed that granules of trial-2B released only 34 percent ± 3 DHA in two minutes compared with trial-1A (57 percent ± 2), trial-1B (48 percent ± 2) and trial-2A (53 percent ± 7). The pleasant taste perception (PTP) test also confirmed the taste masking efficacy of trial-2B (P < 0.05). Scanning electron microscopy (SEM) revealed the more regular and smooth surface of trial-2B granules. In addition, the differential thermal and thermogravimetric analysis (TG-DTA) confirmed no interaction between the materials and pure DHA. DHA has shown its characteristic peaks in the x-ray diffraction (XRD) patterns which were also prominent in all the granules. In conclusion, the granules obtained from trial-2B displayed considerable decrease in the bitter taste of DHA thereby fulfilling the purpose of this study.

O objetivo deste estudo foi o de mascarar o gosto amargo característico da diidroartemisinina (DHA) pelo uso de diferentes materiais de revestimento. Experimento-1 e experimento-2 foram realizados para preparar grânulos de DHA. Os grânulos produzidos pelo experimento-1 mostraram-se irregulares e menores se comparados aos obtidos pelo experimento-2, que foram mais regulares e maiores. Os grânulos obtidos em ambos os experimentos foram, então, revestidos por dois métodos distintos de revestimento, designados como A e B, dependendo do material de revestimento empregado. Os grânulos do experimento-2 mostraram melhor propriedade de fluxo que os obtidos no experimento-1. Estudos de dissolução in vitro em tampão fosfato pH 6,8 revelaram que grânulos do experimento-2B liberaram apenas 34 por cento ± 3 da DHA em dois minutos se comparado com experimento-1A (57 por cento ± 2), experimento-1B (48 por cento ± 2) e experimento-2A (53 por cento ± 7). A Análise Sensorial quanto ao sabor (Pleasant Taste Perception - PTP) também confirmou a eficácia do experimento-2B (P <0,05) em mascarar o gosto amargo da DHA. Microscopia Eletrônica de Varredura (SEM) revelou a superfície mais regular e lisa dos grânulos obtidos pelo experimento-2B. Além disso, Análise Termogravimétrica e Análise Térmica Diferencial (TG-DTA) confirmaram que não há nenhuma interação entre os materiais e a DHA pura. DHA mostrou seus picos característicos na Difração de Raios X (XRD) em padrões que também foram proeminentes em todas as amostras. Em conclusão, os grânulos obtidos pelo experimento-2B exibiram diminuição considerável no gosto amargo da DHA, o que era o propósito deste estudo.

Induction of dihydroartemisinin on prostate cancer PC-3 apoptosis and its mechanism / 中草药

Objective To study the induction of dihydroartemisinin(DHA) on prostate cancer PC-3 apoptosis and its possible mechansim.Methods MTT was employed for cellular viability measurement,flow cytometry(FCM) and transmission electron microscopy(TEM) for observation of apoptosis,and immunocytochemical staining(SP) for analyzing the expression of Bcl-2 and Bax proteins in PC-3 cells treated with DHA of different concentration.Results DHA Significantly inhibited the proliferation of PC-3 cells,induced their apotosis in a time-concentration dependent manner,and led to mitochondrial swelling,nuclear fragmentations and apoptosis body formation,down-expression of Bcl-2 protein,and over-expression of Bax protein correspondence with DHA concentration.Conclusion DHA could induce the apoptosis in PC-3 cells by up-regulating Bax protein and down-regulating Bcl-2 protein.