Designing Artemisinins with Antimalarial Potential, Combining Molecular Electrostatic Potential, Ligand-Heme Interaction and Multivariate Models

Artemisinins tested against W-2 strains of malaria falciparum are investigated with molecular electrostatic potential (MEP), in an attempt to identify key features of the compounds that are necessary for their activities, as well as to investigate likely interactions with the receptor in a biological process and to use that information to propose new molecules. In order to discover the best geometry involving the ligand-receptor complexes (heme) studied and help in the proposition of the new derivatives, molecular simulations of interactions between the most negative charged region around the peroxide and heme locates (the ones around the Fe2+ ion) were carried out. In addition, PCA (principal components analysis), HCA (hierarchical cluster analysis), SDA (stepwise discriminant analysis), and KNN (K-nearest neighbor) multivariate models were employed to investigate which descriptors are responsible for the classification between the higher and lower antimalarial activity of the compounds, and also this information was used to propose new potentially active molecules. The information accumulated in studies of MEP, molecular docking, and multivariate analysis supported the proposal of new structures with potential antimalarial activities. The multivariate models constructed were applied to the new structures and indicated numbers 19 and 20 as the most prominent for syntheses and biological assays.

Potential applications of artemisinins in ocular diseases

Artemisinin, also named qinghaosu, is a family of sesquiterpene trioxane lactone originally derived from the sweet wormwood plant(Artemisia annua), which is a traditional Chinese herb that has been universally used as anti-malarial agents for many years. Evidence has accumulated during the past few years which demonstrated the protective effects of artemisinin and its derivatives(artemisinins) in several other diseases beyond malaria, including cancers, autoimmune disorders, inflammatory diseases, viral and other parasiterelated infections. Recently, this long-considered antimalarial agent has been proved to possess anti-oxidant, anti-inflammatory, anti-apoptotic and anti-excitotoxic properties, which make it a potential treatment option for the ocular environment. In this review, we first described the overview of artemisinins, highlighting the activity of artemisinins to other diseases beyond malaria and the mechanisms of these actions. We then emphasized the main points of published results of using artemisinins in targeting ocular disorders, including uveitis, retinoblastoma, retinal neurodegenerative diseases and ocular neovascularization. To conclude, we believe that artemisinins could also be used as a promising therapeutic drug for ocular diseases, especially retinal vascular diseases in the near future.

More than anti-malarial agents: therapeutic potential of artemisinins in neurodegeneration

Artemisinin,also called qinghaosu,is originally derived from the sweet wormwood plant(Artemisia annua),which is used in traditional Chinese medicine.Artemisinin and its derivatives(artemisinins)have been widely used for many years as anti-malarial agents,with few adverse side effects.Interestingly,evidence has recently shown that artemisinins might have a therapeutic value for several other diseases beyond malaria,including cancers,inflammatory diseases,and autoimmune disorders.Neurodegeneration is a challenging age-associated neurological disorder characterized by deterioration of neuronal structures as well as functions,whereas neuroinflammation has been considered to be an underlying factor in the development of various neurodegenerative disorders,including Alzheimer’s disease.Recently discovered properties of artemisinins suggested that they might be used to treat neurodegenerative disorders by decreasing oxidation,inflammation,and amyloid beta protein(Aβ).In this review,we will introduce artemisinins and highlight the possible mechanisms of their neuroprotective activities,suggesting that artemisinins might have therapeutic potential in neurodegenerative disorders.

GetArtemisininsByAnymeans (GABA)： artemisinins path to conquer diabetes go through GABA receptors

Diabetes is a chronic disease of elevated blood glucose levels that affects more than 400 million people worldwide.Complications of diabetes affect the neuronal and the vascular systems and causes diabetic kidney disease,cardiovascular disease,hypertension,retinopathy,peripheral neuropathy,and diabetic food diseases.Diabetes is caused by either the body’s inability to

Reversal of tamoxifen resistance by artemisinin in ER+breast cancer:bioinformatics analysis and experimental validation

Breast cancer is the leading cause of cancer-related deaths in women worldwide,with Hormone Receptor(HR)+being the predominant subtype.Tamoxifen(TAM)serves as the primary treatment for HR+breast cancer.However,drug resistance often leads to recurrence,underscoring the need to develop new therapies to enhance patient quality of life and reduce recurrence rates.Artemisinin(ART)has demonstrated efficacy in inhibiting the growth of drug-resistant cells,positioning art as a viable option for counteracting endocrine resistance.This study explored the interaction between artemisinin and tamoxifen through a combined approach of bioinformatics analysis and experimental validation.Five characterized genes(ar,cdkn1a,erbb2,esr1,hsp90aa1)and seven drug-disease crossover genes(cyp2e1,rorc,mapk10,glp1r,egfr,pgr,mgll)were identified using WGCNA crossover analysis.Subsequent functional enrichment analyses were conducted.Our findings confirm a significant correlation between key cluster gene expression and immune cell infiltration in tamoxifen-resistant and-sensitized patients.scRNA-seq analysis revealed high expression of key cluster genes in epithelial cells,suggesting artemisinin’s specific impact on tumor cells in estrogen receptor(ER)-positive BC tissues.Molecular target docking and in vitro experiments with artemisinin on LCC9 cells demonstrated a reversal effect in reducing migratory and drug resistance of drug-resistant cells by modulating relevant drug resistance genes.These results indicate that artemisinin could potentially reverse tamoxifen resistance in ER-positive breast cancer.

Nanocarriers to Enhance Solubility, Bioavailability, and Efficacy of Artemisinins

The therapeutic potential of artemisinin (ART) and its derivatives (ARTs) is not limited to malaria but has been recently expanded to other infections with protozoans, trematodes, or viruses as well as to cancer. Due to their limited poor water and oil solubility, rapid degradation by the liver, and short half-life, they have a low bioavailability after oral administration. Consequently, there is a pressing necessity to formulate new ART preparations to raise its bioavailability and efficacy. Nanosized drug delivery systems represent important tools in modern medicine with wide clinical applications, because of their potential modulation of pharmacokinetic and biodistribution. This review focuses on polymer-based systems, lipid-based systems, and inorganic nanoparticles loaded with ARTs. The overall goal of this field of research is to enhance their solubility and stability to improve bioavailability at much lower doses and to increase long-term safety. In addition, the opportunity to reach highly specific site-targeted delivery by these nanocarriers confers a high medicinal value. Remarkably, most of the reported nanoparticulate drug delivery systems are biologically inactive or marginally immunogenic, generating no antigenic or pyrogenic reactions but only partial intrinsic toxicity. As clinical studies in human patients are available so far, there is a pressing need to translate preclinical results on ART-based nanosystems into clinical settings.

通过鉴定关键靶标蛋白探究青蒿素抗疟机制

The widespread use of artemisinin(ART)and its derivatives has significantly reduced the global burden of malaria;however,malaria still poses a serious threat to global health.Although significant progress has been achieved in elucidating the antimalarial mechanisms of ART,the most crucial target proteins and pathways of ART remain unknown.Knowledge on the exact antimalarial mechanisms of ART is urgently needed,as signs of emerging ART resistance have been observed in some regions of the world.Here,we used a combined strategy involving mass spectrometry-coupled cellular thermal shift assay(MS-CETSA)and transcriptomics profiling to identify a group of putative antimalarial targets of ART.We then conducted a series of validation experiments on five prospective protein targets,demonstrating that ART may function against malaria parasites by interfering with redox homeostasis,lipid metabolism,and protein synthesis processes.Taken together,this study provides fresh perspectives on the antimalarial mechanisms of ART and identifies several crucial proteins involved in parasite survival that can be targeted to combat malaria.

Pharmacognostic and phytochemical studies as an invaluable approach for correct identification of medicinal plants:The case of Artemisia vulgaris L.substituted for Artemisia annua L.in Western Uganda

Background:Different parts of Artemisia vulgaris L.(A.vulgaris)are ethno-medicinally used as an emmenagogue and for the treatment of ailments such as malaria fever,ulcers,and cancer.However,anecdotal evidence shows that the plant is often substituted for Artemisia annua L.(A.annua)by herbalists in Western Uganda due to similarities in their morphology.Misidentification of medicinal plants and mislabelling of herbal products have been incriminated in toxicity and adverse health outcomes in traditional medicine practise.Because safety continues to be a major issue with the use of herbal remedies,it becomes imperative therefore that medicinal plants should be correctly identified.Methods:This study focused on investigating the macroscopic,microscopic,physicochemical characteristics and phytochemical composition of A.vulgaris leaves compared to A.annua to ease its correct identification.Results:The results showed that there are some colour differences between the leaves of the two species,with a close arrangement of microscopic features but different leaf constants.The leaves of the two Artemisia species had similar tastes,but their shapes and colours(greenish-yellow for A.annua and dark green for A.vulgaris)can be used by the local community to distinguish between them.The artemisinin content was higher in A.vulgaris leaves(1.72%)than in A.annua(1.43%),but the reverse was observed for the total flavonoid content.Conclusion:This observation could justify the change in the use of A.vulgaris by the indigenous community in western Uganda.Further studies should consider the pharmacognostic comparison of A.annua with other species in the genus Artemisia and the use of molecular techniques such as DNA barcoding.

青蒿素之母——2015年诺贝尔生理学或医学奖新科得主屠呦呦(二)

2015年10月5日,中国中医科学院(原中国中医研究院)终身研究员兼首席研究员、女药学家、药物化学家、医学家和教育家屠呦呦以创制新型抗疟药物——青蒿素及其首个衍生物双氢青蒿素而赢得当年诺贝尔生理学或医学奖之殊荣,特大喜讯传来,国内舆论媒体亢奋,国人无不欢欣鼓舞。屠呦呦先生是首位荣获诺贝尔科学奖的中国大陆本土科学家、首位华裔女性诺奖得主和诺医奖得主,这是中国医学界尤其是中医学界的重大历史性突破,这一荣耀将永远铭记在中国科技发展史上。详细介绍了屠呦呦女士的生平、主要学术成就与贡献、与疟疾直接相关的诺医奖以及青蒿素类抗疟药物获得的各种国内外奖项,简明扼要地阐述了青蒿素类抗疟药物的发现(发明)简史,不惜浓墨重彩全方位地展示了以屠呦呦为杰出代表的中国科学家群英谱的奋斗历程和辉煌成就。

青蒿素之母——2015年诺贝尔生理学或医学奖新科得主屠呦呦(一)

2015年10月5日,中国中医科学院(原中国中医研究院)终身研究员兼首席研究员、女药学家、药物化学家、医学家和教育家屠呦呦以创制新型抗疟药物——青蒿素及其首个衍生物双氢青蒿素而赢得当年诺贝尔生理学或医学奖之殊荣,特大喜讯传来,国内舆论媒体亢奋,国人无不欢欣鼓舞。屠呦呦先生是首位荣获诺贝尔科学奖的中国大陆本土科学家、首位华裔女性诺奖得主和诺医奖得主,这是中国医学界尤其是中医学界的重大历史性突破,这一荣耀将永远铭记在中国科技发展史上。详细介绍了屠呦呦女士的生平、主要学术成就与贡献、与疟疾直接相关的诺医奖以及青蒿素类抗疟药物获得的各种国内外奖项,简明扼要地阐述了青蒿素类抗疟药物的发现(发明)简史,不惜浓墨重彩全方位地展示了以屠呦呦为杰出代表的中国科学家群英谱的奋斗历程和辉煌成就。

青蒿素之母——2015年诺贝尔生理学或医学奖新科得主屠呦呦(三)

2015年10月5日,中国中医科学院(原中国中医研究院)终身研究员兼首席研究员、女药学家、药物化学家、医学家和教育家屠呦呦以创制新型抗疟药物——青蒿素及其首个衍生物双氢青蒿素而赢得当年诺贝尔生理学或医学奖之殊荣,特大喜讯传来,国内舆论媒体亢奋,国人无不欢欣鼓舞。屠呦呦先生是首位荣获诺贝尔科学奖的中国大陆本土科学家、首位华裔女性诺奖得主和诺医奖得主,这是中国医学界尤其是中医学界的重大历史性突破,这一荣耀将永远铭记在中国科技发展史上。详细介绍了屠呦呦女士的生平、主要学术成就与贡献、与疟疾直接相关的诺医奖以及青蒿素类抗疟药物获得的各种国内外奖项,简明扼要地阐述了青蒿素类抗疟药物的发现(发明)简史,不惜浓墨重彩全方位地展示了以屠呦呦为杰出代表的中国科学家群英谱的奋斗历程和辉煌成就。

青蒿素之母——2015年诺贝尔生理学或医学奖新科得主屠呦呦(四)

2015年10月5日,中国中医科学院(原中国中医研究院)终身研究员兼首席研究员、女药学家、药物化学家、医学家和教育家屠呦呦以创制新型抗疟药物——青蒿素及其首个衍生物双氢青蒿素而赢得当年诺贝尔生理学或医学奖之殊荣,特大喜讯传来,国内舆论媒体亢奋,国人无不欢欣鼓舞。屠呦呦先生是首位荣获诺贝尔科学奖的中国大陆本土科学家、首位华裔女性诺奖得主和诺医奖得主,这是中国医学界尤其是中医学界的重大历史性突破,这一荣耀将永远铭记在中国科技发展史上。详细介绍了屠呦呦女士的生平、主要学术成就与贡献、与疟疾直接相关的诺医奖以及青蒿素类抗疟药物获得的各种国内外奖项,简明扼要地阐述了青蒿素类抗疟药物的发现(发明)简史,不惜浓墨重彩全方位地展示了以屠呦呦为杰出代表的中国科学家群英谱的奋斗历程和辉煌成就。

Artemisinin, the Magic Drug Discovered from Traditional Chinese Medicine

Artemisinin and its derivatives represent the most important and influential class of drugs in the fight against malaria. Since the discovery of artemisinin in the early 1970s, the global community has made great strides in characterizing and understanding this remarkable phytochemical and its unique chemical and pharmacological properties. Today, even as artemisinin continues to serve as the foundation for antimalarial therapy, numerous challenges have surfaced in the continued application and development of this family of drugs. These challenges include the emergence of delayed treatment responses to artemisinins in malaria and efforts to apply artemisinins for non-malarial indications. Here, we provide an overview of the story of artemisinin in terms of its past, present, and future. In particular, we comment on the current understanding of the mechanism of action (MOA) of artemisinins, and emphasize the importance of relating mechanistic studies to therapeutic outcomes, both in malarial and non-malarial contexts.

Antitumor Research on Artemisinin and Its Bioactive Derivatives

Cancer is the leading cause of human death which seriously threatens human life.The antimalarial drug artemisinin and its derivatives have been discovered with considerable anticancer properties.Simultaneously,a variety of target-selective artemisinin-related compounds with high efficiency have been discovered.Many researches indicated that artemisinin-related compounds have cytotoxic effects against a variety of cancer cells through pleiotropic effects,including inhibiting the proliferation of tumor cells,promoting apoptosis,inducing cell cycle arrest,disrupting cancer invasion and metastasis,preventing angiogenesis,mediating the tumor-related signaling pathways,and regulating tumor microenvironment.More importantly,artemisinins demonstrated minor side effects to normal cells and manifested the ability to overcome multidrug-resistance which is widely observed in cancer patients.Therefore,we concentrated on the new advances and development of artemisinin and its derivatives as potential antitumor agents in recent 5 years.It is our hope that this review could be helpful for further exploration of novel artemisinin-related antitumor agents.

Differential Effect of Artemisinin Against Cancer Cell Lines

The present study aims at defining the differential cytotoxicity effect of artemisinin toward P815(murin mastocytoma)and BSR(kidney adenocarcinoma of hamster)cell lines.Cytotoxicity was measured by the growth inhibition using MTT assay.These in vitro cytotoxicity studies were complemented by the determination of apoptotic DNA fragmentation and Annexin V-streptavidin-FITC assay.Furthermore,we examined the in vitro synergism between artemisinin and the chemotherapeutic drug,vincristin.The in vivo study was investigated using the DBA2/P815(H2d)mouse model.While artemisinin acted on both tumor cell lines,P815 was much more sensitive to this drug than BSR cells,as revealed by the respective IC50 values(12 lM for P815 and 52 lM for BSR cells).On another hand,and interestingly,apoptosis was induced in P815 but not induced in BSR.These data,reveal an interesting differential cytotoxic effect,suggesting the existence of different molecular interactions between artemisinin and the studied cell lines.In vivo,our results clearly showed that the oral administration of artemisinin inhibited solid tumor development.Our study demonstrates that artemisinin caused differential cytotoxic effects depending not only on the concentration and time of exposure but also on the target cells.

Artemisinin resistance or tolerance in human malaria patients

Malaria is a major cause of morbidity and mortality in the developing world.This situation is mainly due to emergence of resistance to most antimalarial drugs currently available. Artemisinin-based combination treatments are now first-line drugs for Plasmodium falciparum (P.falciparum) malaria.Artemisinin(qinghaosu) and its derivatives are the most rapid acting and efficacious antimalarial drugs.This review highlights most recent investigations into the emergence of artemisinin resistance in falciparum malaria patients on the Thai-Cambodian border,a historical epicenter for multidrug resistance spread spanning over 50 years.The study presents the first evidence that highlights the parasites reduced susceptibility to artemisinin treatment by prolonged parasite-clearance times,raising considerable concern on resistance development.Although the exact mechanism of action remains unresolved,development of resistance was proposed based from both in vitro experiments and human patients.Lines of evidence suggested that the parasites in the patients are in dormant forms,presumably tolerate to the drug pressure.The World Health Organization has launched for prevention and/or containment of the artemisinin-resistant malaria parasites.Taken together,the emergence of artemisinin resistance to the most potent antidote for falciparum malaria,poses a serious threat to global malaria control and prompts renewed efforts for urgent development of new antimalarial weapons.

Treatment of Iron-Loaded Veterinary Sarcoma by Artemisia annua

Artemisinin,a constituent of Artemisia annua L.,is a well-known antimalarial drug.Artemisinin-type drugs also inhibit cancer growth in vitro and in vivo.Herbal extracts of A.annua inhibit the growth of cancer cell lines.Here,we report on the use of capsules containing powder of Herba Artemisiae annuae to treat pet sarcoma.The surgical tumor removal as standard treatment was supplemented by adjuvant therapy with A.annua.One cat and one dog with fibrosarcoma survived 40 and 37 months,respectively,without tumor relapse.Two other dogs suffering from fibrosarcoma and hemangioendothelial sarcoma also showed complete remission and are still alive after 39 and 26 months,respectively.A.annua was well tolerated without noticeable side effects.These four cases indicate that A.annua may be a promising herbal drug for cancer therapy.

Holotransferrin Enhances Selective Anticancer Activity of Artemisinin against Human Hepatocellular Carcinoma Cells

Artemisinin, also termed qinghaosu, is extracted from the traditional Chinese medicine ar- temesia annua L. （the blue-green herb） in the early 1970s, which has been confirmed for effectively treating malaria, Additionally, emerging data prove that artemisinin exhibits anti-cancer effects against many types of cancers such as leukemia, melanoma, etc. Artemisinin becomes cytotoxic in the presence of ferrous iron. Since iron influx is high in cancer cells, artemisinin and its analogs selectively kill can- cer cells with increased intracellular iron concentrations. This study is aimed to investigate the selective inhibitory effects of artemisinin on SMMC-7721 cells in vitro and determine the effect of holotransfer- fin, which increases the concentration of ferrous iron in cancer cells, combined with artemisinin on the anticancer activity. MTT assay was used for assessing the proliferation of SMMC-7721 cells treated with artemisinin. The induction of apoptosis and inhibition of colony formation in SMMC-7721 cells treated with artemisinin were determined by TdT-mediated dUTP nick end labeling （TUNEL） and col- ony formation assay, respectively. The results showed that artemisinin at various concentrations signifi- cantly inhibited growth, colony formation and cell viability of SMMC-7721 cells （P〈0.05）, likely due to induction of apoptosis of SMMC-7721 cells. Of interest, it was found that incubation of artemisinin combined with holotransferrin sensitized the growth inhibitory effect of artemisinin on SMMC-7721 cells （P〈0.01）. Our data suggest that treatment with artemisinin leads to inhibition of viability and pro- liferation, and apoptosis of SMMC-7721 ceils. Furthermore, we observed that holotransferrin signifi- cantly enhanced the anti-cancer activity of artemisinin. This study may provide a potential therapeutic choice for liver cancer.

Antimalarial qinghaosu/artemisinin: The therapy worthy of a Nobel Prize

Malaria is a major cause of human morbidity and mortality in the tropical endemic countries worldwide. This is largely due to the emergence and spread of resistance to most antimalarial drugs currently available. Based on the World Health Organization recommendation, artemisinin-based combination therapies are now used as first-line treatment for Plasmodium falciparum malaria. Artemisinin or qinghaosu(Chinese name) and its derivatives are highly potent, rapidly acting antimalarial drugs. Artemisinin was discovered in 1971 by a Chinese medical scientist Youyou Tu, who was awarded the Nobel Prize in 2015 on her discovering the antimalarial properties of qinghaosu from the traditional Chinese qinghao plant. Nevertheless, artemisinin resistance in falciparum malaria patients has first emerged on the Thai-Cambodian border in 2009, which is now prevalent across mainland Southeast Asia from Vietnam to Myanmar. Here, we reviewed malaria disease severity, history of artemisinin discovery, chemical structure, mechanism of drug action, artemisinin-based combination therapies, emergence and spread of drug resistance, including the recent findings on mechanism of resistance in the falciparum malaria parasite. This poses a serious threat to global malaria control and prompts renewed efforts for the urgent development of new antimalarial drugs.

Trichome-Specific Expression of Amorpha-4,11-Diene Synthase, a Key Enzyme of Artemisinin Biosynthesis in <i>Artemisia annua</i>L., as Reported by a Promoter-GUS Fusion

Artemisia annua L. produces small amounts of the sesquiterpenoid artemisinin, which is used for treatment of malaria. A worldwide shortage of the drug has led to intense research to increase the yield of artemisinin in the plant. In order to study the regulation of expression of a key enzyme of artemisinin biosynthesis, the promoter region of the key enzyme amorpha-4,11-diene synthase (ADS) was cloned and fused with the β-glucuronidase (GUS) reporter gene. Transgenic plants of A. annua expressing this fusion were generated and studied. Transgenic plants expressing the GUS gene were used to establish the activity of the cloned promoter by a GUS activity staining procedure. GUS under the control of the ADS promoter showed specific expression in glandular trichomes. The activity of the ADS promoter varies temporally and in old tissues essentially no GUS staining could be observed. The expression pattern of GUS and ADS in aerial parts of the transgenic plant was essentially the same indicating that the cis-elements controlling glandular trichome specific expression are included in the cloned promoter. However, some cis-element(s) that control expression in root and old leaf appears to be missing in the cloned promoter. Furthermore, qPCR was used to compare the activity of the wild-type ADS promoter with that of the cloned ADS promoter. The latter promoter showed a considerably lower activity than the wild-type promoter as judged from the levels of GUS and ADS transcripts, respectively, which may be due to the removal of an enhancing cis-element from the ADS promoter. The ADS gene is specifically expressed in stalk and secretory cells of glandular trichomes of A. annua.