Dihydroartemisinin ameliorates innate inflammatory response induced by Streptococcus suis-derived muramidase-released protein via inactivation of TLR4-dependent NF-kB signaling

Muramidase-released protein(MRP)is now being recognized as a critical indicator of the virulence and pathogenicity of Streptococcus suis(S.suis).However,the identification of viable therapeutics for S.suis infection was hindered by the absence of an explicit mechanism for MRP-actuated inflammation.Dihydroartemisinin(DhA)is an artemisinin derivative with potential anti-inflammatory activity.The modulatory effect of DhA on the inflammatory response mediated by the virulence factor MRP remains obscure.This research aimed to identify the signaling mechanism by which MRP triggers the innate immune response in mouse spleen and cultured macrophages.With the candidate mechanism in mind,we investigated DhA for its ability to dampen the pro-inflammatory response induced by MRP.The innate immune response in mice was drastically triggered by MRP,manifesting as splenic and systemic inflammation with splenomegaly,immune cell infiltration,and an elevation in pro-inflammatory cytokines.A crucial role for Toll-like receptor 4(TLR4)in coordinating the MRP-mediated inflammatory response via nuclear factor-kappa B(NF-kB)activation was revealed by TLR4 blockade.In addition,NFkB-dependent transducer and activator of transcription 3(STAT3)and mitogen-activated protein kinases(MAPKs)activation was required for the inflammatory signal transduction engendered by MRP.Intriguingly,we observed an alleviation effect of DhA on the MRP-induced immune response,which referred to the suppression of TLR4-mediated actuation of NF-kB-STAT3/MAPK cascades.The inflammatory response elicited by MRP is relevant to TLR4-dependent NF-kB activation,followed by an increase in the activity of STAT3 or MAPKs.DhA mitigates the inflammation process induced by MRP via blocking the TLR4 cascade,highlighting the therapeutic potential of DhA in targeting S.suis infection diseases.

Dihydroartemisinin inhibits plasmid transfer in drug-resistant Escherichia coli via limiting energy supply

Conjugative transfer of antibiotic resistance genes(ARGs)by plasmids is an important route for ARG dissemination.An increasing number of antibiotic and nonantibiotic compounds have been reported to aid the spread of ARGs,highlighting potential challenges for controlling this type of horizontal transfer.Development of conjugation inhibitors that block or delay the transfer of ARG-bearing plasmids is a promising strategy to control the propagation of antibiotic resistance.Although such inhibitors are rare,they typically exhibit relatively high toxicity and low efficacy in vivo and their mechanisms of action are inadequately understood.Here,we studied the effects of dihydroartemisinin(DHA),an artemisinin derivative used to treat malaria,on conjugation.DHA inhibited the conjugation of the IncI2 and IncX4 plasmids carrying the mobile colistin resistance gene(mcr-1)by more than 160-fold in vitro in Escherichia coli,and more than two-fold(IncI2 plasmid)in vivo in a mouse model.It also suppressed the transfer of the IncX3 plasmid carrying the carbapenem resistance gene bla_(NDM-5)by more than twofold in vitro.Detection of intracellular adenosine triphosphate(ATP)and proton motive force(PMF),in combination with transcriptomic and metabolomic analyses,revealed that DHA impaired the function of the electron transport chain(ETC)by inhibiting the tricarboxylic acid(TCA)cycle pathway,thereby disrupting PMF and limiting the availability of intracellular ATP for plasmid conjugative transfer.Furthermore,expression levels of genes related to conjugation and pilus generation were significantly down-regulated during DHA exposure,indicating that the transfer apparatus for conjugation may be inhibited.Our findings provide new insights into the control of antibiotic resistance and the potential use of DHA.

Dihydroartemisinin enhances cell apoptosis in diffuse large B cell lymphoma by inhibiting the STAT3 activity

Background:Dihydroartemisinin(DHA)is reported to be a potential anticancer agent,and the mechanisms underlying the effects of DHA on diffuse large B cell lymphoma however are still obscure.This study aimed to assess the antitumor effect of DHA on diffuse large B cell lymphoma cells and to determine the potential underlying mechanisms of DHA-induced cell apoptosis.Methods:Here,the Cell Counting Kit 8 assay was conducted to study cell proliferation.We performed Annexin V-FITC/propidium iodide staining,real-time polymerase chain reaction,and western blot analysis to analyze cell apoptosis and potential molecular mechanisms.Results:The results showed that DHA substantially suppressed cell proliferation and induced cell apoptosis in vitro in a time-and concentration-dependent fashion.Moreover,STAT3 activity could be inhibited after stimulation with DHA.Conclusion:These results imply that the underlying anti-tumoral effect of DHA may increase apoptosis in diffuse large B cell lymphoma cells via the STAT3 signaling pathway.In addition,DHA might be an effective drug for diffuse large B cell lymphoma therapy.

Histopathological Evaluation of the Cardiotoxicity of Dihydroartemisinin-Piperaquine on Male Albino Rats

Problem Statement: Malaria’s global impact necessitates effective treatments, like dihydroartemisinin-piperaquine (DHA/PQP), though safety concerns, notably drug-induced cardiotoxicity (DICT), persist. A knowledge gap exists regarding DHA/PQP’s cardiac effects, warranting a comprehensive investigation. Approach: This study aimed to assess KROSH (DHA/PQP) impact on albino rat heart histology, examining structural changes and potential cardiotoxicity. 40 albino rats were grouped by KROSH dosage and duration, monitored for weight changes, and heart tissues were examined using hematoxylin and eosin (H & E) staining. Statistical analysis compared to control and treated groups. Results: KROSH administration led to varying rat weight effects, yet not statistically significant. Histological analysis revealed dose and duration-dependent cardiac tissue alterations, including distortion, adipose deposits, artery hypertrophy, fibrosis, and necrosis. These contrasts with prior research documenting DHA/PQP’s non-toxic effects. Conclusion/Recommendation: This study highlights potential KROSH (DHA/PQP) cardiotoxicity concerns through histological changes, underscoring the need for further research into underlying mechanisms and human health implications. Given DHA/PQP’s wide use, these findings should inform safety evaluations and administration practices.

Development of nanoscale drug delivery systems of dihydroartemisinin for cancer therapy: A review

Dihydroartemisinin(DHA),a first-line antimalarial drug,has demonstrated great anticancer effects in many types of tumors,including liver cancer,glioblastoma,and pancreatic cancer.Due to its abilities to induce programmed cell death(PCD;apoptosis,autophagy and ferroptosis),inhibit tumor metastasis and angiogenesis,and modulate the tumor microenvironment,DHA could become an antineoplastic agent in the foreseeable future.However,the therapeutic efficacy of DHA is compromised owing to its inherent disadvantages,including poor stability,low aqueous solubility,and short plasma halflife.To overcome these drawbacks,nanoscale drug delivery systems(NDDSs),such as polymeric nanoparticles(NPs),liposomes,and metal-organic frameworks(MOFs),have been introduced to maximize the therapeutic efficacy of DHA in either single-drug or multidrug therapy.Based on the beneficial properties of NDDSs,including enhanced stability and solubility of the drug,prolonged circulation time and selective accumulation in tumors,the outcomes of DHA-loaded NDDSs for cancer therapy are significantly improved compared to those of free DHA.This reviewfirst summarizes the current understanding of the anticancer mechanisms of DHA and then provides an overview of DHA-including nanomedicines,aiming to provide inspiration for further application of DHA as an anticancer drug.

Topical dihydroartemisinin inhibits suture-induced neovascularization in rat corneas through ERK1/2 and p38 pathways

AIM: To determine if topical instillation of dihydroartemisinin (DHA) inhibits corneal neovascularization (NV) in rats and to investigate the role of the extracellular regulated kinases (ERK) 1/2 and p38 pathways in this process. O METHODS: Suture-induced corneal NV was produced in rats and the eyes were topically treated with different concentrations of DHA (20mg/L, 10mg/L or 5mg/L) or normal saline 4 times a day for 7 days. The corneal NV was quantified as the proportion of NV area to the whole cornea. Western blot was used to determine the expressions of vascular endothelial growth factor (VEGF) and the phosphorylation status of VEGF receptor-2, ERK1/2 and p38 in the corneas. Immunofluorescent staining was used to determine the expressions of phospho-ERK1/2 and phospho-p38 in the corneal tissues from the eyes treated with 20 mg/L DHA (DHA group) or normal saline (control group). RESULTS: The proportion of corneal NV area in the eyes treated with normal saline or DHA at dosages of 20mg/L, 10mg/L or 5mg/L was (23.74 +/- 3.00)%, (15.73 +/- 2.88)%, (19.53 +/- 2.42)%, and (23.38 +/- 2.79)%, respectively. In the eyes treated with 20mg/L or 10mg/L DHA, the corneal NV area was significantly reduced when compared to that in eyes with normal saline (P < 0.05). Western blot analyses revealed that 20mg/L DHA significantly inhibited the expressions of VEGF and phospho-VEGFR-2. Both 20mg/L and 10mg/L DHA inhibited the expressions of phospho-ERK1/2 and phospho-p38. Immunofluorescent staining further demonstrated that 20mg/L DHA lowered the Expression levels of phospho-ERK1/2 and phospho-p38 in the corneas with suture-induced NV. O CONCLUSION: Suture-induced NV in rat corneas was significantly inhibited by topical treatment with 20mg/L and 10mg/L DHA. The results suggest that the effects could be partially dependent on the DHA-mediated inhibitions of the ERK1/2 and p38 pathways.

The inhibitory effect of dihydroartemisinin on the growth of neuroblastoma cells

Objective:To evaluate the inhibitory effect of dihydroartemisinin on neuroblastoma cell line SH-SY5 Y,explore the possible mechanism of dihydroartemisinin against neuroblastoma cells.Methods:The cell viability of dihydroartemisinin treated SH-SY5 Y cells was examined by MTT assay and morphology of cells was observed by using inverted microscope.Cell cycle was examined with flowcytometry assay,then cyclin D1 and caspase-3 proteins expression was detected by ELISA and western blotting assay.Results:MTT analysis results showed that cell viability significantly decreased after exposure to 0.05,0.50,5.00 and 50.00 mmol/L dihydroartemisinin in a dose-dependent manner,and the lower density of cells was observed in treated groups.The number of cells in sub-G1 phase was increased after treatment with different doses of dihydroartemisinin compared with the control group.The expression of cyclin D1 protein was decreased,while the expression of caspase-3 protein was increased in treated group.Conclusions:Dihydroartemisinin could inhibit the proliferation through stopping the cell cycle and inducing the apoptosis in neuroblastoma SH-SY5 Y cells.

Inhibition of lymphangiogenesis,nodal and lung metastasis by dihydroartemisinin in mice bearing Lewis lung carcinoma

Objective:To investigate the activity of anti-malarial dihydroartemisinin (DHA) on tumor growth, lymphangiogenesis, nodal and lung metastasis and survival in mice bearing Lewis lung carcimoma (LLC). Methods: The models of C57BL/6 mice transplantation tumors were established via subcutaneous injection of LLC cells and divided into 4 groups: control group, DHA group, DHA+ferrous sulfate (FS) group and FS group, with 25 mice in each group. Tumor volumes and weights, nodal and lung metastasis, and survival were monitored. Tumor lymphatic microvessel density (LMVD) was determined by lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) immnohistochemistry. After LLC cells were treated with DHA or DHA+FS, protein and mRNA levels of vascular endothelial growth factor (VEGF) -C were evaluated by Western blotting and real time quantitative RT-PCR, respectively. Results: Oral administration of DHA or DHA+FS inhibited lymph node and lung metastasis, and prolonged survival. However, no significant tumor growth retardation effect was observed when mice were treated with DHA alone. The inhibited tumor metastasis was related to the decreased LMVD in the peritumoral regions, but not in the intratumoral regions. DHA significantly down-regulated the expression of VEGF-C protein and mRNA in LLC cells. Conclusion: DHA effectively inhibits LLC transplantation tumor lymphangiogenesis, nodal and lung metastasis, and may be a promising chemotherapeutic agent for controlling lung cancer metastasis by decreasing VEGF-C expression.

Dihydroartemisinin attenuates ischemia/reperfusion-induced renal tubular senescence by activating autophagy

Acute kidney injury(AKI)is an important factor for the occurrence and development of CKD.The protective effect of dihydroartemisinin on AKI and and reported mechanism have not been reported.In this study,we used two animal models including ischemia-reperfusion and UUO,as well as a high-glucose-stimulated HK-2 cell model,to evaluate the protective effect of dihydroartemisinin on premature senescence of renal tubular epithelial cells in vitro and in vivo.We demonstrated that dihydroartemisinin improved renal aging and renal injury by activating autophagy.In addition,we found that co-treatment with chloroquine,an autophagy inhibitor,abolished the anti-renal aging effect of dihydroartemisinin in vitro.These findings suggested that activation of autophagy/elimination of senescent cell might be a useful strategy to prevent AKI/UUO induced renal tubular senescence and fibrosis.

Dihydroartemisinin increased the abundance of Akkermansia muciniphila by YAP1 depression that sensitizes hepatocellular carcinoma to anti-PD-1 immunotherapy

The effect of anti-programmed cell death 1(anti-PD-1)immunotherapy is limited in patients with hepatocellular carcinoma(HCC).Yes-associated protein 1(YAP1)expression increased in liver tumor cells in early HCC,and Akkermansia muciniphila abundance decreased in the colon.The response to anti-PD-1 treatment is associated with A.muciniphila abundance in many tumors.However,the interaction between A.muciniphila abundance and YAP1 expression remains unclear in HCC.Here,anti-PD-1 treatment decreased A.muciniphila abundance in the colon,but increased YAP1 expression in the tumor cells by mice with liver tumors in situ.Mechanistically,hepatocyte-specific Yap1 knockout(Yap1^(LKO))maintained bile acid homeostasis in the liver,resulting in an increased abundance of A.muciniphila in the colon.Yap1 knockout enhanced anti-PD-1 efficacy.Therefore,YAP1 inhibition is a potential target for increasing A.muciniphila abundance to promote anti-PD-1 efficacy in liver tumors.Dihydroartemisinin(DHA),acting as YAP1 inhibitor,increased A.muciniphila abundance to sensitize anti-PD-1 therapy.A.muciniphila by gavage increased the number and activation of CD8^(+)T cells in liver tumor niches during DHA treatment or combination with anti-PD-1.Our findings suggested that the combination anti-PD-1 with DHA is an effective strategy for liver tumor treatment.

A metal-organic framework-based redox homeostasis disruptor selectively potentiate the cytotoxicity of dihydroartemisinin for cancer therapy

Artemisinin and its derivatives have emerged as promising therapeutic agents for cancer therapy by endogenous iron-mediated generation of free radicals.However,the enhanced antioxidant defense systems in cancer cells provide them with resistance to oxidative damage,greatly antagonizing the therapeutic efficacy that relies on inducing oxidative stress.Herein,a metal-organic framework(MOF)-based nanoplatform(CMD)is constructed to disrupt the cellular redox homeostasis and selectively potentiate the cytotoxicity of dihydroartemisinin for cancer therapy.In cancer cells,the copper(II)sites in the MOF nanocarrier of CMD can efficiently weaken the cellular antioxidant capacity by depleting the overexpressed glutathione,simultaneously leading to the decomposition of the framework structure and the release of the encapsulated dihydroartemisinin.As a result,the damaged antioxidant defense system of cancer cells reduces its effect on oxidative stress alleviation and strengthens the therapeutic efficacy of dihydroartemisinin.On contrast,the low concentration of cellular glutathione in normal cells protects them from dihydroartemisinin-induced cytotoxicity by decelerating the drug release.In vivo results demonstrate that CMD could completely suppress the tumor growth in mice and show no evidence of toxicity,providing an effective strategy for the practical usage of dihydroartemisinin in cancer therapy.

双氢青蒿素对胃癌SGC-7901细胞凋亡和侵袭能力的影响

目的初步探讨检测双氢青蒿素(Dihydroartemisinin,DHA)对胃癌SGC-7901细胞凋亡和侵袭能力作用的可能机制。方法以胃癌SGC-7901细胞为研究对象,实验分为空白组和DHA低(40μmol/L)、中(80μmol/L)、高剂量组(120μmol/L)。CCK-8检测法检测不同浓度DHA对SGC-7901细胞增殖的影响;Hoechst 33258染色法观察各组细胞形态变化;采用流式细胞术检测不同给药组的细胞凋亡情况;Transwell法检测不同浓度DHA对SGC-7901细胞侵袭能力的影响;Western blot检测Bcl-2、Bax、cleaved caspase-3和VEGF蛋白表达。结果CCK-8检测法显示,与空白组相比,DHA各浓度组的细胞增殖受到明显抑制,且随着药物浓度的增加呈现剂量依赖性;Hoechst 33258染色结果显示,DHA各浓度组的SGC-7901细胞核内出现明显固缩,且着色增强;流式细胞术结果显示,给药组凋亡细胞数量明显增多,且与给药浓度成正比;Transwell检测结果显示,DHA各浓度组中穿透基质膜的细胞数量明显下降;Western blot检测结果显示,与空白组相比,DHA各浓度组Bax和cleaved caspase-3蛋白表达显著上升(P<0.05),Bcl-2、VEGF蛋白表达显著降低(P<0.05)。结论DHA可能通过调控Bcl-2、Bax、cleaved caspase-3表达,抑制SGC-7901细胞增殖并诱导细胞凋亡,通过调控VEGF表达降低SGC-7901细胞的侵袭能力。

双氢青蒿素通过激活氯通道促进鼻咽癌CNE-2Z细胞放疗敏感性

目的:探讨ClC-3氯通道在双氢青蒿素(DHA)促进鼻咽癌CNE-2Z细胞放射增敏中的作用。方法:MTT法检测DHA对CNE-2Z细胞和正常鼻咽上皮NP69-SV40T细胞活力的抑制作用;集落形成实验检测DHA对CNE-2Z细胞的放射增敏作用;Western blot检测ClC-3蛋白的表达;siRNA技术下调ClC-3蛋白的表达;全细胞膜片钳技术记录细胞氯电流。结果:(1)相较于NP69-SV40T细胞,DHA可选择性抑制CNE-2Z细胞活力,IC_(10)值分别为(13.020±4.831)μmol/L和(5.244±1.050)μmol/L(P<0.01);(2)集落形成实验结果显示,DHA对CNE-2Z细胞具有放疗增敏作用,放射增敏比为1.9;(3)DHA能激活CNE-2Z细胞的氯通道,产生外向氯电流;但对NP69-SV40T细胞的氯通道则无影响;(4)DHA促进CNE-2Z细胞的ClC-3氯通道蛋白的表达(P<0.01);(5)氯通道阻断剂NPPB可抑制DHA对CNE-2Z细胞的放射增敏作用,抑制比达1.84;同时也抑制DHA激活的氯电流;(6)下调CNE-2Z的ClC-3蛋白可抑制DHA对鼻咽癌CNE-2Z细胞的放射增敏作用,抑制比达4.19;DHA对CNE-2Z细胞的氯电流的激活作用则不再产生。结论:DHA对鼻咽癌CNE-2Z细胞产生放疗增敏作用,很可能与ClC-3氯通道被激活有关。

二氢青蒿素对衰老细胞的作用及机制

目的 探究二氢青蒿素对衰老细胞的作用及其机制。方法 利用双氧水诱导小鼠成纤维细胞(NIH3T3)构建应激早衰模型(SIPS),通过衰老特异性标记物SA-β-半乳糖苷酶染色、蛋白质印迹技术进行SIPS鉴定;细胞实验分为对照组(磷酸盐缓冲液+二甲基亚砜)、模型组(双氧水+二甲基亚砜)、药物组(双氧水+二氢青蒿素),采用Cell Counting Kit-8(CCK-8)法、乳酸脱氢酶法、SA-β-半乳糖苷酶染色、细胞内铁含量测定、蛋白质印迹技术、荧光探针染色及流式细胞术检测二氢青蒿素对衰老细胞的影响。结果 CCK-8结果显示,二氢青蒿素作用模型组24 h的半数抑制浓度(IC50)为(8.26±0.66)μmol/L;与对照组相比,模型组存活率降低,且呈剂量依耐性;蛋白质印迹结果显示,与模型组相比,药物组铁蛋白重链(FTH)及谷胱甘肽过氧化酶4(GPX4)蛋白表达水平降低(P<0.05),细胞内铁、活性氧(ROS)含量增加(P<0.05)。结论 二氢青蒿素可特异性诱导衰老细胞死亡,其机制与铁死亡有关。

双氢青蒿素通过诱导自噬抑制口腔鳞状细胞癌细胞增殖

目的探讨双氢青蒿素(DHA)对人口腔鳞癌细胞增殖能力的影响及其作用机制。方法用不同浓度的双氢青蒿素干预CAL27细胞,采用CCK-8法检测其细胞增殖活力,集落形成实验检测细胞克隆形成能力;基于网络药理学和生物信息学筛选DHA抑制口腔癌生物学行为的潜在靶点;不同浓度的DHA干预CAL27细胞后,Western blot检测增殖相关蛋白PCNA和自噬相关蛋白Beclin-1、LC3的表达;联合自噬阻断剂3-甲基腺嘌呤和自噬诱导剂雷帕霉素与双氢青蒿素共处理细胞后,检测细胞增殖活力、克隆形成能力和增殖及自噬相关蛋白的表达。结果双氢青蒿素显著降低了CAL27细胞的增殖活力及克隆形成能力,且呈现浓度依赖性,PCNA的表达量也显著下降。网络药理学结合生物信息学发现DHA抑制口腔癌的靶点涉及自噬相关通路。DHA干预可升高细胞内自噬相关蛋白Beclin-1、LC3的表达,DHA联合自噬阻断剂共处理CAL27后,细胞的增殖活力及克隆形成能力降低,PCNA的表达升高、Beclin-1、LC3的表达降低。结论双氢青蒿素可在体外抑制口腔鳞癌细胞的增殖能力,其作用机制可能与诱导细胞自噬相关。

二氢青蒿素结合SERCA2b诱导结肠癌HCT-116细胞凋亡的机制研究

目的探讨二氢青蒿素(DHA)与肌浆/内质网钙ATP酶(SERCA)的结合位点及其通过线粒体途径诱导人结肠癌HCT-116细胞凋亡的作用机制。方法分别于不同浓度(0,10,20,40μmol/L)DHA环境中培养HCT-116细胞24 h后,用Western blotting检测细胞中SERCA2蛋白表达水平;CCK-8法检测细胞增殖情况;行Hoechst核染色;用JC-1探针检测细胞线粒体膜电位。通过LeDock分子对接方法,预测DHA与SERCA的结合位点。基于生物膜干涉技术,将合成的Ile315与Thr316位点突变后的SERCA2b突变蛋白和非突变蛋白分别与小分子DHA进行结合检测。结果Western blotting与CCK-8检测结果显示,随着DHA浓度升高,SERCA2蛋白表达水平显著下降,细胞增殖显著降低,并呈剂量相关(P<0.01)。Hoechst核染色显示,DHA诱导了HCT-116细胞核变圆、固缩。JC-1探针检测结果表明,在DHA处理4 h内,线粒体膜电位逐渐降低,其后线粒体膜电位则出现明显降低。分子对接预测提示DHA与Thr316形成氢键相互作用,与Ile315则有疏水相互作用。进一步的生物膜干涉技术提示DHA与SERCA2b非突变蛋白结合信号良好,而与Ile315与Thr316位点突变后的SERCA2b突变蛋白结合信号较差。结论DHA可直接与SERCA2b的Ile315与Thr316位点结合,并通过线粒体途径诱导结肠癌HCT-116细胞凋亡。

双氢青蒿素对非小细胞肺癌细胞诱导的CD8^(+)T细胞抗肿瘤免疫应答的影响

目的探讨青蒿素衍生物双氢青蒿素(DHA)对非小细胞肺癌(NSCLC)细胞诱导的CD8^(+)T细胞抗肿瘤免疫功能的调控作用。方法将NSCLC细胞系A549细胞分为二甲基亚砜(DMSO)对照组和DHA处理组;分别用DMSO和不同浓度的DHA(25、50和100μmol/L)处理A549细胞,根据半抑制浓度(IC 50)选择最适浓度的DHA处理A549细胞0、24、48、72 h;CCK-8法和集落形成实验检测DHA对A549细胞增殖和集落形成能力的影响;密度梯度离心法分离健康个体外周血单个核细胞(PBMC),经黏附贴壁法去除单核细胞,随后与丝裂霉素C预处理的A549细胞按照10∶1比例共培养,2周后采用流式细胞术分别检测CD8^(+)T细胞比例及其穿孔素和颗粒酶B的表达水平。结果与对照组相比,25、50和100μmol/L DHA处理24 h后的A549细胞增殖的抑制率均升高(P<0.01);DHA对A549细胞的IC 50为46.26μmol/L;依据IC 50浓度检测50μmol/L DHA处理A549细胞0、24、48、72 h的细胞抑制率分别为1.53%、53.50%、63.84%和69.91%,分别与前一观察时间点即0、24和48 h相比,细胞抑制率均增高(P<0.01);集落形成实验结果显示,与对照组相比,DHA处理组的A549细胞集落形成数减少(P<0.01);流式细胞术结果显示,与对照组相比,DHA预处理组的A549细胞在共培养体系中诱导的CD8^(+)T细胞的比例、表达穿孔素和颗粒酶B的CD8^(+)T细胞比例均更高(P<0.01)。结论DHA能够抑制NSCLC细胞生长,促进NSCLC细胞诱导的CD8^(+)T细胞抗肿瘤免疫应答。

双氢青蒿素抗消化道恶性肿瘤作用及机制研究进展

中国是消化道肿瘤较为流行的国家,尽管近十年来在肿瘤筛查、诊断和治疗方面取得了很大进步,但化疗仍然是治疗晚期癌症的主要方法,多重耐药性以及严重不良反应导致大多数晚期患者预后不良。天然分子产物协同抗癌药物增强抗肿瘤效果是一种临床上有前途的策略。双氢青蒿素(dihydroartemisinin,DHA)作为青蒿素的主要活性代谢产物,具有较强的抗疟活性和抗肿瘤作用,其抗肿瘤机制主要是通过加速Fe^(2+)介导的细胞氧化损伤、诱导肿瘤细胞凋亡、停滞细胞周期、抑制肿瘤血管生成、逆转肿瘤细胞的多耐药性等发挥作用。本文主要对DHA的抗消化道肿瘤作用以及分子机制做一综述。

Dietary dihydroartemisinin supplementation alleviates intestinal inflammatory injury through TLR4/NOD/NF-kB signaling pathway in weaned piglets with intrauterine growth retardation

The aim of present study was to evaluate whether diets supplemented with dihydroartemisinin(DHA)could alleviate intestinal inflammatory injury in weaned piglets with intrauterine growth retardation(IUGR).Twelve normal birth weight(NBW)piglets and 12 piglets with IUGR were fed a basal diet(NBW-CON and IUCR-CON groups),and another 12 piglets with IUGR were fed the basal diet supplemented with DHA at 80 mg/kg(IUGR-DHA group)from 21 to 49 d of age.At 49 d of age,8 piglets with similar body weight in each group were sacrificed.The jejunal and ileal samples were collected for further analysis.The results showed that IUGR impaired intestinal morphology,increased intestinal inflamma-tory response,raised enterocyte apoptosis and reduced enterocyte proliferation and activated trans-membrane toll-like receptor 4(TLR4)/nucleotide-binding and oligomerization domain(NOD)/nuclear factor-kB(NF-kB)signaling pathway.Dihydroartemisinin inclusion ameliorated intestinal morphology,indicated by increased villus height,villus height-to-crypt depth ratio,villus surface area and decreased villus width of piglets with IUGR(P<0.05).Compared with NBW piglets,IUGR piglets supplemented with DHA exhibited higher apoptosis index and caspase-3 expression,and lower proliferation index and proliferating cell nuclear antigen expression in the intestine(P<0.05).Dihydroartemisinin supple-mentation attenuated the intestinal inflammation of piglets with IUGR,indicated by increased concen-trations of intestinal inflammatory cytokines and lipopolysaccharides(P<0.05).In addition,DHA supplementation down-regulated the related mRNA expressions of TLR4/NOD/NF-kB signaling pathway and upregulated mRNA expressions of negative regulators of TLR4 and NOD signaling pathway in the intestine of piglets with IUGR(P<0.05).Piglets in the IUGR-DHA group showed lower protein ex-pressions of TLR4,phosphorylated NF-kB(pNF-kB)inhibitorα,nuclear pNF-kB,and higher protein expression of cytoplasmic pNF-kB in the intestine than those in the IUGR-CON group(P<0.05).In conclusion,DHA supplementation could improve intestinal morphology,regulate enterocyte prolifera-tion and apoptosis,and alleviate intestinal inflammation through TLR4/NOD/NF-kB signaling pathway in weaned piglets with IUGR.