Toxicity of the antimalarial artemisinin and its dervatives

Effect of Artemisia annua on anticoccidial action, intestinal microbiota and metabolites of Hu lambs

BACKGROUND

Coccidia are among the primary pathogens causing diarrhea and even fatalities in lambs. With the increasing use of chemical drugs to treat coccidiosis, the problem of drug resistance is becoming more and more threatening. Therefore, there is an urgent need to identify novel alternative drugs for the treatment of the lamb coccidia. In this study, the effect of different doses and extraction methods of Artemisia annua (A. annua) on anticoccidial activity and growth performance was assessed by oocysts output (OPG), fecal index, average daily gain (ADG) and the new production value of experimental lambs. High-throughput sequencing technology was employed to investigate the effect of A. annua on the intestinal microbiota and metabolites of lambs afflicted with coccidiosis.

RESULTS

The results revealed that all A. annua treatment groups exhibited good anticoccidial effects. According to the soft stool index and ADG analysis, the Low-dose A. annua (AL) and A. annua alcohol extract (AA) groups demonstrated a better overall effect. The microbiota and metabolites of lambs changed after A. annua was administered. Unclassified_Muribaculaceae exhibited a significant positive correlation with ADG (P < 0.05) and a negative correlation with OPG, although the latter was not statistically significant (P > 0.05). Alistipes displayed a significant negative correlation with ADG (P < 0.05), and a positive correlation with OPG (P > 0.05). Additionally, UCG 005 exhibited a highly significant negative correlation with OPG (P < 0.01).

CONCLUSION

The above results demonstrated that AL and AA groups had more effective anticoccidial action. Unclassified_Muribaculaceae could be employed as a suitable probiotic to enhance weight gain in lambs, while UCG-005 could inhibit intestinal Eimeria colonization in lambs. Alistipes may serve as a biomarker for predicting the risk of intestinal coccidia outbreaks in lambs. A. annua induced significant changes in gut microbiota, accompanied by corresponding changes in metabolites. These differences in gut microbiota and metabolites provide valuable insights for subsequent research on the mechanisms underlying anticoccidial action.

Artemisinin-Quinidine Combination for Suppressing Ventricular Tachyarrhythmia in an Ex Vivo Model of Brugada Syndrome

BACKGROUND

The ionic mechanism underlying Brugada syndrome (BrS) arises from an imbalance in transient outward current flow between the epicardium and endocardium. Previous studies report that artemisinin, originally derived from a Chinese herb for antimalarial use, inhibits the Ito current in canines. In a prior study, we showed the antiarrhythmic effects of artemisinin in BrS wedge preparation models. However, quinidine remains a well-established antiarrhythmic agent for treating BrS. Therefore, this study aims to investigate the efficacy of combining artemisinin with low-dose quinidine in suppressing ventricular tachyarrhythmia (VTA) in experimental canine BrS models.

METHODS

Transmural pseudo-electrocardiogram and epicardial/endocardial action potential (AP) were recorded from coronary-perfused canine right ventricular wedge preparation. To mimic the BrS model, acetylcholine (3 μM), calcium channel blocker verapamil (1 μM), and Ito agonist NS5806 (6-10 μM) were administered until VTA was induced. Subsequently, low-dose quinidine (1-2 μM) combined with artemisinin (100 μM) was perfused to mitigate VTA. Key parameters, including AP duration, J wave area, notch index, and T wave dispersion, were measured.

RESULTS

After administering the provocation agents, all sample models exhibited prominent J waves and VTA. Artemisinin alone (100-150 μM) suppressed VTA and restored the AP dome in all three preparations. Its infusion resulted in reductions in the J wave area and epicardial notch index. Consequently, low-dose quinidine (1-2 μM) did not fully restore the AP dome in all six sample models. However, when combined with additional artemisinin (100 μM), low-dose quinidine effectively suppressed VTA in all six models and restored the AP dome while also decreasing the J wave area and epicardial notch index.

CONCLUSION

Low-dose quinidine alone fails to fully alleviate VTA in the BrS wedge model. However, its combination with artemisinin effectively suppresses VTA. Artemisinin may reduce the therapeutic dose of quinidine, potentially minimizing its associated adverse effects.

NDV targets the invasion pathway in malaria parasite through cell surface sialic acid interaction

Merozoites utilize sialic acids on the red blood cell (RBC) cell surface to rapidly adhere to and invade the RBCs. Newcastle disease virus (NDV) displays a strong affinity toward membrane-bound sialic acids. Incubation of NDV with the malaria parasites dose-dependently reduces its cellular viability. The antiplasmodial activity of NDV is specific, as incubation with Japanese encephalitis virus, duck enteritis virus, infectious bronchitis virus, and influenza virus did not affect the parasite propagation. Interestingly, NDV is reducing more than 80% invasion when RBCs are pretreated with the virus. Removal of the RBC surface proteins or the NDV coat proteins results in disruption of the virus binding to RBC. It suggests the involvement of specific protein: ligand interaction in virus binding. We established that the virus engages with the parasitized RBCs (PRBCs) through its hemagglutinin neuraminidase (HN) protein by recognizing sialic acid-containing glycoproteins on the cell surface. Blocking of the HN protein with free sialic acid or anti-HN antibodies abolished the virus binding as well as its ability to reduce parasite growth. Interestingly, the purified HN from the virus alone could inhibit the parasite's growth in a dose-dependent manner. NDV binds strongly to knobless murine parasite strain Plasmodium yoelii and restricted the parasite growth in mice. Furthermore, the virus was found to preferentially target the PRBCs compared to normal erythrocytes. Immunolocalization studies reveal that NDV is localized on the plasma membrane as well as weakly inside the PRBC. NDV causes neither any infection nor aggregation of the human RBCs. Our findings suggest that NDV is a potential candidate for developing targeted drug delivery platforms for the Plasmodium-infected RBCs.

Targeting ferroptosis using Chinese herbal compounds to treat respiratory diseases

BACKGROUND

Respiratory diseases pose a grave threat to human life. Therefore, understanding their pathogenesis and therapeutic strategy is important. Ferroptosis is a novel type of iron-dependent programmed cell death, distinct from apoptosis, necroptosis, and autophagy, characterised by iron, reactive oxygen species, and lipid peroxide accumulation, as well as glutathione (GSH) depletion and GSH peroxidase 4 (GPX4) inactivation. A close association between ferroptosis and the onset and progression of respiratory diseases, including chronic obstructive pulmonary disease, acute lung injury, bronchial asthma, pulmonary fibrosis, and lung cancer, has been reported. Recent studies have shown that traditional Chinese medicine (TCM) compounds exhibit unique advantages in the treatment of respiratory diseases owing to their natural properties and potential efficacy. These compounds can effectively regulate ferroptosis by modulating several key signalling pathways such as system Xc- -GSH-GPX4, NCOA4-mediated ferritinophagy, Nrf2-GPX4, and Nrf2/HO-1, thus playing a positive role in improving respiratory diseases.

PURPOSE

This comprehensive review systematically outlines the regulatory role of ferroptosis in the onset and progression of respiratory diseases and provides evidence for treating respiratory diseases by targeting ferroptosis with TCM compounds. These insights aim to offer potential remedies for the clinical prevention and treatment of respiratory diseases.

STUDY DESIGN AND METHODS

We searched scientific databases PubMed, Web of Science, Scopus, and CNKI using keywords such as "ferroptosis","respiratory diseases","chronic obstructive pulmonary disease","bronchial asthma","acute lung injury","pulmonary fibrosis","lung cancer","traditional Chinese medicine","traditional Chinese medicine compound","monomer", and "natural product" to retrieve studies on the therapeutic potential of TCM compounds in ameliorating respiratory diseases by targeting ferroptosis. The retrieved data followed PRISMA criteria (preferred reporting items for systematic review).

RESULTS

TCM compounds possess unique advantages in treating respiratory diseases, stemming from their natural origins and proven clinical effectiveness. TCM compounds can exert therapeutic effects on respiratory diseases by regulating ferroptosis, which mainly involves modulation of pathways such as system Xc- -GSH-GPX4,NCOA4-mediated ferritinophagy, Nrf2-GPX4, and Nrf2/HO-1.

CONCLUSION

TCM compounds have demonstrated promising potential in improving respiratory diseases through the regulation of ferroptosis. The identification of specific TCM-related inducers and inhibitors of ferroptosis holds great significance in developing more effective strategies. However, current research remains confined to animal and cellular studies, emphasizing the imperative for further verifications through high-quality clinical data.

The potential application and molecular mechanisms of natural products in the treatment of allergic rhinitis: A review

BACKGROUNDS

Allergic rhinitis (AR) is a non-infectious chronic inflammation of the nasal mucosa mainly mediated by immunoglobulin E (IgE) in atopic individuals after exposure to allergens. The application of AR guideline-recommended pharmacotherapies can rapidly relieve symptoms of AR but with poor long-term efficacy, and many of these therapies have side effects. Many natural products and their derivatives have shown potential therapeutic effects on AR with fewer side effects.

OBJECTIVES

This review aims to expand understanding of the roles and mechanisms of natural compounds in the treatment of AR and to highlight the importance of utilizing natural products in the treatment of AR.

MATERIAL AND METHOD

We conducted a systematic literature search using PubMed, Web of Science, Google Scholar, and Clinical Trials. The search was performed using keywords including natural products, natural compounds, bioproducts, plant extracts, naturally derived products, natural resources, allergic rhinitis, hay fever, pollinosis, nasal allergy. Comprehensive research and compilation of existing literature were conducted.

RESULTS

This article provided a comprehensive review of the potential therapeutic effects and mechanisms of natural compounds in the treatment of AR. We emphasized that natural products primarily exert their effects by modulating signalling pathways such as NF-κB, MAPKs, STAT3/ROR-γt/Foxp3, and GATA3/T-bet, thereby inhibiting the activation and expansion of allergic inflammation. We also discussed their toxicity and clinical applications in AR therapy.

CONCLUSION

Taken together, natural products exhibit great potential in the treatment of AR. This review is also expected to facilitate the application of natural products as candidates for treating AR. Furthermore, drug discovery based on natural products has a promising prospect in AR treatment.

The Anticancer Activities of Natural Terpenoids That Inhibit Both Melanoma and Non-Melanoma Skin Cancers

The prevalence of two major types of skin cancer, melanoma and non-melanoma skin cancer, has been increasing worldwide. Skin cancer incidence is estimated to rise continuously over the next 20 years due to ozone depletion and an increased life expectancy. Chemotherapeutic agents could affect healthy cells, and thus may be toxic to them and cause numerous side effects or drug resistance. Phytochemicals that are naturally occurring in fruits, plants, and herbs are known to possess various bioactive properties, including anticancer properties. Although the effects of phytochemicals are relatively milder than chemotherapeutic agents, the long-term intake of phytochemicals may be effective and safe in preventing tumor development in humans. Diverse phytochemicals have shown anti-tumorigenic activities for either melanoma or non-melanoma skin cancer. In this review, we focused on summarizing recent research findings of the natural and dietary terpenoids (eucalyptol, eugenol, geraniol, linalool, and ursolic acid) that have anticancer activities for both melanoma and non-melanoma skin cancers. These terpenoids may be helpful to protect skin collectively to prevent tumorigenesis of both melanoma and nonmelanoma skin cancers.

Artemisinin suppressed tumour growth and induced vascular normalisation in oral squamous cell carcinoma via inhibition of macrophage migration inhibitory factor

BACKGROUND

Tumour vascular normalisation therapy advocates a balance between pro-angiogenic factors and anti-angiogenic factors in tumours. Artemisinin (ART), which is derived from traditional Chinese medicine, has been shown to inhibit tumour growth; however, the relationship between ART and tumour vascular normalisation in oral squamous cell carcinoma (OSCC) has not been previously reported.

METHODS

Different concentrations(0 mg/kg, 25 mg/kg, 50 mg/kg, 100 mg/kg)of ART were used to treat the xenograft nude mice model of OSCC. The effects of ART on migration and proliferation of OSCC and human umbilical vein endothelial cells (HUVEC) cells were detected by scratch assay and CCK-8 assay. OSCC cells with macrophage migration inhibitory factor (MIF) silenced were constructed to explore the effect of MIF.

RESULTS

Treatment with ART inhibited the growth and angiogenesis of OSCC xenografts in nude mice and downregulated vascular endothelial growth factor (VEGF), IL-8, and MIF expression levels. ART reduced the proliferation, migration, and tube formation of HUVEC, as well as the expression of VEGFR1 and VEGFR2. When the dose of ART was 50 mg/kg, vascular normalisation of OSCC xenografts was induced. Moreover, VEGF and IL-8 were needed in rhMIF restoring tumour growth and inhibit vascular normalisation after the addition of rhMIF to ART-treated cells.

CONCLUSION

Artemisinin might induce vascular normalisation and inhibit tumour growth in OSCC through the MIF-signalling pathway.

Therapeutic potential of dihydroartemisinin in mitigating radiation-induced lung injury: Inhibition of ferroptosis through Nrf2/HO-1 pathways in mice

BACKGROUND

Radiation-induced lung injury (RILI) is a common consequence of thoracic radiation therapy that lacks effective preventative and treatment strategies. Dihydroartemisinin (DHA), a derivative of artemisinin, affects oxidative stress, immunomodulation, and inflammation. It is uncertain whether DHA reduces RILI. In this work, we investigated the specific mechanisms of action of DHA in RILI.

METHODS

Twenty-four C57BL/6J mice were randomly divided into four groups of six mice each: Control group, irradiation (IR) group, IR + DHA group, and IR + DHA + Brusatol group. The IR group received no interventions along with radiation treatment. Mice were killed 30 days after the irradiation. Morphologic and pathologic changes in lung tissue were observed with hematoxylin and eosin staining. Detection of hydroxyproline levels for assessing the extent of pulmonary fibrosis. Tumor necrosis factor α (TNF-α), transforming growth factor-β (TGF-β), glutathione peroxidase (GPX4), Nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) expression in lung tissues were detected. In addition, mitochondrial ultrastructural changes in lung tissues were also observed, and the glutathione (GSH) content in lung tissues was assessed.

RESULTS

DHA attenuated radiation-induced pathological lung injury and hydroxyproline levels. Additionally, it decreased TNF-α and TGF-β after irradiation. DHA may additionally stimulate the Nrf2/HO-1 pathway. DHA upregulated GPX4 and GSH levels and inhibited cellular ferroptosis. Brusatol reversed the inhibitory effect of DHA on ferroptosis and its protective effect on RILI.

CONCLUSION

DHA modulated the Nrf2/HO-1 pathway to prevent cellular ferroptosis, which reduced RILI. Therefore, DHA could be a potential drug for the treatment of RILI.

Artesunate in glioblastoma therapy: Case reports and review of clinical studies

BACKGROUND

Artesunate, a derivative of the active ingredient artemisinin from Artemisia annua L. used for centuries in the traditional Chinese medicine, is being applied as front-line drug in malaria treatment. As it is cytotoxic for cancer cells, trials are ongoing to include this drug as supplement in cancer therapy. In glioblastoma cells, artesunate was shown to induce oxidative stress, DNA base damage and double-strand breaks (DSBs), apoptosis, and necroptosis. It also inhibits DNA repair functions and bears senolytic activity. Compared to ionizing radiation, DNA damages accumulate over the whole exposure period, which makes the agent unique in its genotoxic profile. Artesunate has been used in adjuvant therapy of various cancers.

PURPOSE

As artesunate has been used in adjuvant therapy of different types of cancer and clinical trials are lacking in brain cancer, we investigated its activity in glioma patients with focus on possible side effects.

STUDY DESIGN

Between 2014 and 2020, twelve patients were treated with artesunate for relapsing glioma and analyzed retrospectively: 8 males and 4 females, median age 45 years.

HISTOLOGY

4 glioblastomas WHO grade 4, 5 astrocytomas WHO grade 3, 3 oligodendrogliomas grade 2 or 3. All patients were pretreated with radiation and temozolomide-based chemotherapy. Artesunate 100 mg was applied twice daily p.o. combined with dose-dense temozolomide alone (100 mg/m2 day 1-5/7, 10 patients) or with temozolomide (50 mg/m2 day 1-5/7) plus lomustine (CCNU, 40 mg day 6/7). Blood count, C-reactive protein (CRP), liver enzymes, and renal parameters were monitored weekly.

RESULTS

Apart from one transient grade 3 hematological toxicity, artesunate was well tolerated. No liver toxicity was observed. While 8 patients with late stage of the disease had a median survival of 5 months after initiation of artesunate treatment, 4 patients with treatment for remission maintenance showed a median survival of 46 months. We also review clinical trials that have been performed in other cancers where artesunate was included in the treatment regimen.

CONCLUSIONS

Artesunate administered at a dose of 2 × 100 mg/day was without harmful side effects, even if combined with alkylating agents used in glioma therapy. Thus, the phytochemical, which is also utilized as food supplement, is an interesting, well tolerated supportive agent useful for long-term maintenance treatment. Being itself cytotoxic on glioblastoma cells and enhancing the cytotoxicity of temozolomide as well as in view of its senolytic activity, artesunate has clearly a potential to enhance the efficacy of malignant brain cancer therapy.

The cross-linking and protective effect of artemisinin and its derivatives on collagen fibers of demineralized dentin surface

OBJECTIVE

To investigate the cross-linking and protective effect of artemisinin (ART), dihydroartemisinin (DHA), and artesunate (AST) on collagen fibers of demineralized dentin surface.

METHODS

Molecular docking was used to predict potential interactions of ART, DHA, and AST with dentin type I collagen. Human third molars without caries were completely demineralized and treated with different solutions for 1 min. The molecular interactions and cross-linking degree of ART and its derivatives with dentin collagen were evaluated by FTIR spectroscopy, total extractable protein content, and a ninhydrin assay. Scanning electron microscopy, hydroxyproline release, and ultimate microtensile strength tests (μUTS) were employed to confirm the mechanical properties and anti-collagenase degradation properties of dentin collagen fibers.

RESULTS

ART, DHA, and AST combined with dentin type I collagen mainly through hydrogen bonding and hydrophobic interactions, and the cross-linking reaction sites were mainly C=O and CN functional groups. Compared to the control group, ART and its derivatives significantly increased the degree of cross-linking. Additionally, significant increases were observed in resistance to enzymatic digestion and mechanical properties of the artemisinin and its derivatives group.

CONCLUSION

ART, DHA, and AST could cross-link with demineralized dentin collagen, through improving the mechanical properties and anti-collagenase degradation properties.

CLINICAL SIGNIFICANCE

The study endorses the potential use of ART and its derivatives as a prospective collagen cross-linking agent for degradation-resistant and long-period dentin bonding in composite resin restorations.

Acute and subacute oral toxicity of artemisinin-hydroxychloroquine sulfate tablets in beagle dogs

Artemisinin-hydroxychloroquine sulfate tablets (AH) are regarded as a relatively inexpensive and novel combination therapy for the treatment of various forms of malaria, particularly aminoquinoline drugs-resistant strains of Plasmodium falciparum. Our aim was to conduct acute and subacute oral toxicity studies in non-rodents to obtain more nonclinical data on the safety of AH. Acute toxicity evaluation was performed in beagle dogs at single doses of 230, 530, 790, 1180, 2660, and 5000 mg/kg. Beagle dogs at doses of 0, 56, 84, and 126 mg/kg were used to assess subacute toxicity for 14 days. The approximate lethal dose range for acute oral administration of AH in dogs is found to be 790-1180 mg/kg, and toxic symptoms prior to death include gait instability, limb weakness, mental fatigue, tachypnea, and convulsion. Repeated doses of AH in dogs caused vomiting, soft feces, decreased activity, anorexia, and splenic red pulp vacuolation. Of note, AH could reduce body weight gain and prolong the QTc interval of individual dogs. Therefore, the no-observed-adverse-effect level (NOAEL) and lowest-observed-adverse-effect level (LOAEL) of oral administration of AH for 14 days in dogs are determined to be 84 mg/kg and 126 mg/kg, respectively.

GPX4 inhibition synergistically boosts mitochondria targeting nanoartemisinin-induced apoptosis/ferroptosis combination cancer therapy

Artemisinin, originally used for its antimalarial activity, has received much attention in recent years for cancer therapy. The anticancer mechanisms of artemisinin are complicated and debatable. Challenges in the delivery of artemisinin also persist because the anticancer effect of artemisinin alone is often not satisfactory when used with traditional nanocarriers. We herein report the mitochondrial delivery of artemisinin with extremely high anticancer capacity. The action mode of artemisinin in the mitochondria of cancer cells includes heme-participating and oxygen-independent conversion of artemisinin into a carbon-centered radical, which is partly converted into ROS in the presence of molecular oxygen. We reveal that artemisinin alone in the mitochondria can induce strong cancer cell apoptosis. In addition, due to the weak inhibition of GPX4 activity by artemisinin, weak ferroptosis is also observed. We further discover that GPX4 activity in MCF-7 cells is greatly inhibited by RSL3 to synergistically enhance the anticancer capacity of artemisinin via enhancing ferroptosis. The synergistic anticancer activity of artemisinin and RSL3 in the mitochondria not only improves cancer cell-killing ability, but also inhibits the re-proliferation of residual cancer cells. This study provides a new insight into developing highly efficient and practical artemisinin nanomedicines for cancer therapy.

A Review of the Potential Benefits of Herbal Medicines, Small Molecules of Natural Sources, and Supplements for Health Promotion in Lupus Conditions

The Latin word lupus, meaning wolf, was in the medical literature prior to the 1200s to describe skin lesions that devour flesh, and the resources available to physicians to help people were limited. The present text reviews the ethnobotanical and pharmacological aspects of medicinal plants and purified molecules from natural sources with efficacy against lupus conditions. Among these molecules are artemisinin and its derivatives, antroquinonol, baicalin, curcumin, emodin, mangiferin, salvianolic acid A, triptolide, the total glycosides of paeony (TGP), and other supplements such as fatty acids and vitamins. In addition, medicinal plants, herbal remedies, mushrooms, and fungi that have been investigated for their effects on different lupus conditions through clinical trials, in vivo, in vitro, or in silico studies are reviewed. A special emphasis was placed on clinical trials, active phytochemicals, and their mechanisms of action. This review can be helpful for researchers in designing new goal-oriented studies. It can also help practitioners gain insight into recent updates on supplements that might help patients suffering from lupus conditions.

In Vitro Inhibition of Xanthine Oxidase Purified from Arthritis Serum Patients by Nanocurcumin and Artemisinin Active Compounds

Curcumin and artemisinin are commonly used in traditional East Asian medicine. In this study, we investigated the inhibitory effects of these active compounds on xanthine oxidase (XO) using allopurinol as a control. XO was purified from the serum of arthritis patients through ammonium sulfate precipitation (65%) and ion exchange chromatography on diethylaminoethyl (DEAE)-cellulose. The specific activity of the purified enzyme was 32.5 U/mg protein, resulting in a 7-fold purification with a yield of 66.8%. Molecular docking analysis revealed that curcumin had the strongest interaction energy with XO, with a binding energy of -9.28 kcal/mol. The amino acid residues Thr1077, Gln762, Phe914, Ala1078, Val1011, Glu1194, and Ala1079 were located closer to the binding site of curcumin than artemisinin, which had a binding energy of -7.2 kcal/mol. In vitro inhibition assays were performed using nanocurcumin and artemisinin at concentrations of 5, 10, 15, 20, and 25 µg/mL. Curcumin inhibited enzyme activity by 67-91%, while artemisinin had a lower inhibition ratio, which ranged from 40-70% compared to allopurinol as a control.

Pharmacovigilance of herbal medicines: Concerns and future prospects

ETHNOPHARMACOLOGICAL RELEVANCE

The use of herbal medicines for prophylaxis, prevention, and treatment of various ailments is rising throughout the world because they are thought to be safer than allopathic treatments, which they are. However, several investigations have documented the toxicity and adverse drug reactions (ADR) of certain formulations and botanicals if not consumed wisely.

AIM OF THE STUDY

The goal of the current study is to address herbal medication pharmacovigilance (PV) modeling and related considerations for improved patient safety. Also, focus is laid on the comprehensive and critical analysis of the current state of PV for herbal medications at the national and international levels.

MATERIALS AND METHODS

Targeted review also known as focused literature review methodology was utilized for exploring the data from various scientific platforms such as Science Direct, Wiley Online Library, Springer, PubMed, Google Scholar using "pharmacovigilance, herbal medicine, traditional medicine, ADR, under reporting, herb toxicity, herb interactions" as keywords along with standard literature pertaining to herbal medicines that is published by the WHO and other international and national organizations etc. The botanical names mentioned in the present article were authenticated using World Flora Online database.

RESULTS

The historical developments paving the way for PV in regulatory setup were also discussed, along with various criteria's for monitoring herbal medicine, ADR of herbs, phytoconstituents, and traditional medicines, herb-drug interactions, modes of reporting ADR, databases for reporting ADR's, provisions of PV in regulatory framework of different nations, challenges and way forward in PV are discussed in detail advocating a robust drug safety ecosystem for herbal medicines.

CONCLUSION

Despite recent efforts to encourage the reporting of suspected ADRs linked to herbal medicines, such as expanding the programme and adding community pharmacists and other healthcare professionals as recognized reporters, the number of herbal ADR reports received by the regulatory bodies remains comparatively low. Since users often do not seek professional advice or report if they have side effects, under-reporting, is anticipated to be significant for herbal medications. There are inadequate quality control methods, poor regulatory oversight considering herbs used in food and botanicals, and unregulated distribution channels. In addition, botanical identity, traceability of herbs, ecological concerns, over-the-counter (OTC) herbal medicines, patient-physicians barriers requires special focus by the regulatory bodies for improved global safety of herbal medicines.

Comparative assessment of hepatoprotective properties of Artesunate and flavonoids from Artemisia annua on acetaminophen and carbon tetrachloride-induced cytotoxicity in primary mice hepatocytes

Background

Artesunate (ART) is a semi-synthetized molecule from Artemisinin, an active compound isolated from the medicinal plant Artemisia annua, widely used for the treatment of malaria. Previous studies reported that ART may exert a dual effect on the liver. Accordingly, this study investigated the potential protective action of ART against Acetaminophen (APAP) and Carbon tetrachloride (CCl₄)-induced hepatotoxicity in primary mice hepatocytes, in comparison to that of flavonoid extracted from A. annua (FAA). In addition, the antioxidant properties of FAA were also assessed.

Methods

The antioxidant activities of FAA and Ascorbic acid (ASC) (0.01-100 μg/mL) were assessed through inhibition of lipid peroxidation, reduction of ferric and phosphomolydenum, and hydroxyl and DPPH radicals scavenging assays. The hepatoprotective effects of FAA and ART (0.1-100 μg/mL) were evaluated against APAP (11 mM) or CCl4 (4 mM) induced oxidative damage in primary mouse hepatocytes. Biochemical parameters associated with hepatotoxicity assessed include cell viability, cell membrane integrity, cellular glutathione, and antioxidant enzyme activities.

Results

The obtained finding revealed FAA displayed a remarkable antioxidant activities as evidenced by the low IC₅₀/EC₅₀ values (3.85-19.32 μg/mL), comparable to that of ASC (3.26-18.04 μg/mL). When tested at 10 μg/mL, both FAA and ART significantly (p˂0.05) preserved cell viability, inhibited alanine aminotransferase leakage and lipid membrane peroxidation, and restored superoxide dismutase and catalase activities and glutathione content induced by APAP or CCl₄ in a similar way as Silymarin. However, ART showed a significant (p˂0.05) cytotoxic effect on hepatocytes at 100 and 1000 μg/mL and did not confer obvious protection at 100 μg/mL.

Conclusion

Overall, our data demonstrated that ART harms mice hepatocytes at high concentration while conferring relative protection against APAP and CCl₄-hepatotoxicity at low concentration. In contrast, FAA effectively protects liver cells without cytotoxicity effect, event at 100 μg/mL. Accordingly, ART should be given to the patient only under a medical prescription.

Secondary Metabolites Isolated from Artemisia afra and Artemisia annua and Their Anti-Malarial, Anti-Inflammatory and Immunomodulating Properties-Pharmacokinetics and Pharmacodynamics: A Review

There are over 500 species of the genus Artemisia in the Asteraceae family distributed over the globe, with varying potentials to treat different ailments. Following the isolation of artemisinin (a potent anti-malarial compound with a sesquiterpene backbone) from Artemisia annua, the phytochemical composition of this species has been of interest over recent decades. Additionally, the number of phytochemical investigations of other species, including those of Artemisia afra in a search for new molecules with pharmacological potentials, has increased in recent years. This has led to the isolation of several compounds from both species, including a majority of monoterpenes, sesquiterpenes, and polyphenols with varying pharmacological activities. This review aims to discuss the most important compounds present in both plant species with anti-malarial properties, anti-inflammatory potentials, and immunomodulating properties, with an emphasis on their pharmacokinetics and pharmacodynamics properties. Additionally, the toxicity of both plants and their anti-malaria properties, including those of other species in the genus Artemisia, is discussed. As such, data were collected via a thorough literature search in web databases, such as ResearchGate, ScienceDirect, Google scholar, PubMed, Phytochemical and Ethnobotanical databases, up to 2022. A distinction was made between compounds involved in a direct anti-plasmodial activity and those expressing anti-inflammatory and immunomodulating activities or anti-fever properties. For pharmacokinetics activities, a distinction was made between compounds influencing bioavailability (CYP effect or P-Glycoprotein effect) and those affecting the stability of pharmacodynamic active components.

Artemisinin exerts a protective effect in the MPTP mouse model of Parkinson's disease by inhibiting microglial activation via the TLR4/Myd88/NF-KB pathway

AIMS

We performed cell and animal experiments to explore the therapeutic effect of artemisinin on Parkinson's disease (PD) and the TLR4/Myd88 signaling pathway.

METHODS

C57 mice were randomly divided into the blank, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced and artemisinin-treated groups. Clinical symptoms, the number of dopaminergic (DAergic) neurons in the substantia nigra, and microglial cell activation were compared among the three groups. Subsequently, BV-2 cell activation and TLR4/Myd88 pathway component expression were compared among the blank, MPP⁺ -treated, artemisinin-treated, and TLR4 activator-treated groups.

RESULTS

Behavioral symptoms were improved, the number of DAergic neurons in the substantia nigra of the midbrain was increased, and microglial cell activation was decreased in artemisinin-treated MPTP-induced PD model mice compared with control-treated MPTP-induced PD model mice (p < 0.05). The cell experiments revealed that artemisinin treatment reduced MPP⁺ -induced BV-2 cell activation and inhibited the TLR4/Myd88 signaling pathway. Moreover, the effect of artemisinin on the BV-2 cell model was inhibited by the TLR4 activator LPS (p < 0.05).

CONCLUSION

Artemisinin may reduce damage to DAergic neurons in a PD mouse model by decreasing microglial activation through the TLR4-mediated MyD88-dependent signaling pathway. However, this finding cannot explain the relationship between microglia and DAergic neurons.

Inhibitory effects of sesquiterpene lactones on the aggregation and cytotoxicity of prion neuropeptide

The misfolding and conformational transformation of prion protein (PrP) are crucial to the progression of prion diseases. Screening for available natural inhibitors against prion proteins can contribute to the rational design and development of new anti-prion drugs and therapeutic strategies. The prion neuropeptide, PrP106-126 is commonly used as a model peptide of the abnormal PrP^Sc, and a number of potential inhibitors were explored against the amyloid fibril formation of PrP106-126. The well-known sesquiterpene lactone, artemisinin, shows diverse biological functions in anti-malarial, anti-cancer and lowering glucose. However, its inhibitory effect on PrP106-126 fibrillation is unclear. In this work, we selected two sesquiterpene lactones, artemisinin (1) and artesunate (2), to explore their roles in PrP106-126 aggregation by a series of physicochemical and biochemical methods. The results demonstrated that 1 and 2 could effectively impede the formation of amyloid fibrils and remodel the preformed fibrils. The binding of the small molecules to PrP106-126 was dominated by electrostatic, hydrophobic and hydrogen bonding interactions. In addition, both compounds exhibited neuroprotective effects by reducing peptide oligomerization. 2 showed better inhibition and regulation on peptide aggregation and cellular viability than 1 due to its specific succinate modification. Our study provides the information of sesquiterpene lactones to prevent PrP fibril formation and other related amyloidosis.

Artemisinin Loaded Cerium-Doped Nanopowders Improved In Vitro the Biomineralization in Human Periodontal Ligament Cells

BACKGROUND

A promising strategy to enhance bone regeneration is the use of bioactive materials doped with metallic ions with therapeutic effects and their combination with active substances and/or drugs. The aim of the present study was to investigate the osteogenic capacity of human periodontal ligament cells (hPDLCs) in culture with artemisinin (ART)-loaded Ce-doped calcium silicate nanopowders (NPs); Methods: Mesoporous silica, calcium-doped and calcium/cerium-doped silicate NPs were synthesized via a surfactant-assisted cooperative self-assembly process. Human periodontal ligament cells (hPDLCs) were isolated and tested for their osteogenic differentiation in the presence of ART-loaded and unloaded NPs through alkaline phosphatase (ALP) activity and Alizarine red S staining, while their antioxidant capacity was also evaluated; Results: ART promoted further the osteogenic differentiation of hPDLCs in the presence of Ce-doped NPs. Higher amounts of Ce in the ART-loaded NPs inversely affected the mineral deposition process by the hPDLCs. ART and Ce in the NPs have a synergistic role controlling the redox status and reducing ROS production from the hPDLCs; Conclusions: By monitoring the Ce amount and ART concentration, mesoporous NPs with optimum properties can be developed towards bone tissue regeneration demonstrating also potential application in periodontal tissue regeneration strategies.

Post-Artesunate Delayed Hemolysis: A Review of Current Evidence

Artesunate is the drug of choice for treating patients with severe malaria. Post-artesunate delayed hemolysis (PADH) is an uncommon adverse event from malaria treatment. Most patients with PADH are non-immune travelers. The pathophysiology of PADH is not fully understood, but the most likely mechanism is "pitting", in which red blood cells carrying dead parasites killed by artesunate's action are directed to the spleen for clearing the dead parasites. After the cleansing process, these red blood cells re-enter the circulation but with a smaller size and impaired integrity, resulting in a shortened lifespan of 7-21 days. Therefore, most patients with PADH usually present with clinical features of hemolytic anemia 7 days or later after the initiation of artesunate. To date, the benefits of artesunate treatment outweigh its adverse events, and no fatal cases have resulted from PADH. However, the hematological follow-up of patients with malaria treated with artesunate is recommended for clinicians to detect any delayed hemolytic event early and prevent potentially serious consequences.

Artemisia spp.: An Update on Its Chemical Composition, Pharmacological and Toxicological Profiles

Artemisia plants are traditional and ethnopharmacologically used to treat several diseases and in addition in food, spices, and beverages. The genus is widely distributed in all continents except the Antarctica, and traditional medicine has been used as antimalarial, antioxidant, anticancer, antinociceptive, anti-inflammatory, and antiviral agents. This review is aimed at systematizing scientific data on the geographical distribution, chemical composition, and pharmacological and toxicological profiles of the Artemisia genus. Data from the literature on Artemisia plants were taken using electronic databases such as PubMed/MEDLINE, Scopus, and Web of Science. Selected papers for this updated study included data about phytochemicals, preclinical pharmacological experimental studies with molecular mechanisms included, clinical studies, and toxicological and safety data. In addition, ancient texts and books were consulted. The essential oils and phytochemicals of the Artemisia genus have reported important biological activities, among them the artemisinin, a sesquiterpene lactone, with antimalarial activity. Artemisia absinthium L. is one of the most famous Artemisia spp. due to its use in the production of the absinthe drink which is restricted in most countries because of neurotoxicity. The analyzed studies confirmed that Artemisia plants have many traditional and pharmacological applications. However, scientific data are limited to clinical and toxicological research. Therefore, further research is needed on these aspects to understand the full therapeutic potential and molecular pharmacological mechanisms of this medicinal species.

Protective Effect and Possible Mechanisms of Artemisinin and Its Derivatives for Diabetic Nephropathy: A Systematic Review and Meta-Analysis in Animal Models

Background

Artemisinin and its derivatives have potential antidiabetic effects. There is no evaluation of reported studies in the literature on the treatment of diabetic nephropathy (DN), one of the commonest diabetic microangiopathies, with artemisinins. Here, we aimed to evaluate preclinical evidence for the efficacy and possible mechanisms of artemisinins in reducing diabetic renal injury.

Methods

We conducted an electronic literature search in fourteen databases from their inception to November 2021. All animal studies assessing the efficacy and safety of artemisinins in DN were included, regardless of publication or language. Overall, 178 articles were screened according to predefined inclusion and exclusion criteria. Finally, 18 eligible articles were included in this systematic review. The SYstematic Review Center for Laboratory animal Experimentation (SYRCLE) risk-of-bias tool was used to assess the risk of bias in the included studies. The primary outcomes were kidney function, proteinuria, and renal pathology. Secondary endpoints included changes in fasting plasma glucose (FPG) levels, body weight, and relevant mechanisms.

Results

Of the 18 included articles involving 418 animal models of DN, 1, 2, 6, and 9 used dihydroartemisinin, artemether, artesunate, and artemisinin, respectively. Overall, artemisinins reduced indicators of renal function, including blood urea nitrogen (P < 0.00001), serum creatinine (P < 0.00001), and kidney index (P = 0.0001) compared with control group treatment. Measurements of proteinuria (P < 0.00001), microalbuminuria (P < 0.05), and protein excretion (P = 0.0002) suggested that treatment with artemisinins reduced protein loss in animals with DN. Artemisinins may lower blood glucose levels (P = 0.01), but there is a risk of weight gain (P < 0.00001). Possible mechanisms of action of artemisinins include delaying renal fibrosis, reducing oxidative stress, and exerting antiapoptotic and anti-inflammatory effects.

Conclusion

Available evidence suggests that artemisinins may be protective against renal injury secondary to diabetes in preclinical studies; however, high-quality and long-term trials are needed to reliably determine the balance of benefits and harms.

Artemisinin and l-carnitine combination therapy alters the erythrocytes redox status

Hematopoiesis is a sensitive target of artemisinin (ART) and its derivatives, and hemolysis is one of their commonly reported side effects. L-carnitine (LC), an amino acid derivative involved in lipid metabolism, is beneficial for hematological parameters. Sixty adult laboratory mice were randomly divided into six groups. Group I (control) received saline and corn oil; groups II and III received therapeutic (50 mg/kg) and toxic (250 mg/kg) doses of ART, respectively; groups IV and V received 370 mg/kg LC along with the 50 and 250 mg/kg ART, respectively; and group VI received 370 mg/kg LC. Drugs were administered orally for seven consecutive days. The erythrocyte glucose 6-phosphate dehydrogenase (G6PD), catalase (CAT), and peroxidase (POX) activity, and the reduced glutathione (GSH) level were assessed by colorimetric methods. ART reduced the G6PD activity both at therapeutic and toxic doses. The therapeutic dose of ART reduced the CAT activity and the GSH level, non-significantly. The toxic dose of ART reduced the CAT activity and increased the POX activity. LC reduced the G6PD, CAT, and POX activities and increased GSH level. The therapeutic dose of ART and LC showed synergy in reducing the G6PD activity. LC and ART combination reduced POX activity and increased GSH level without any significant effect on the CAT activity. Inhibition of G6PD may be a potentially new mechanism of ART action. Co-administration of LC with ART or following treatment with ART may have protective effects on erythrocytes. This article is protected by copyright. All rights reserved.

Discovery and repurposing of artemisinin

Malaria is an ancient infectious disease that threatens millions of lives globally even today. The discovery of artemisinin, inspired by traditional Chinese medicine (TCM), has brought in a paradigm shift and been recognized as the “best hope for the treatment of malaria” by World Health Organization. With its high potency and low toxicity, the wide use of artemisinin effectively treats the otherwise drug-resistant parasites and helps many countries, including China, to eventually eradicate malaria. Here, we will first review the initial discovery of artemisinin, an extraordinary journey that was in stark contrast with many drugs in western medicine. We will then discuss how artemisinin and its derivatives could be repurposed to treat cancer, inflammation, immunoregulation-related diseases, and COVID-19. Finally, we will discuss the implications of the “artemisinin story” and how that can better guide the development of TCM today. We believe that artemisinin is just a starting point and TCM will play an even bigger role in healthcare in the 21st century.

Acute and subacute oral toxicity of artemisinin-hydroxychloroquine sulfate tablets in rats

Artemisinin-hydroxychloroquine sulfate tablets (AH) are considered a relatively inexpensive and novel combination therapy for treating all forms of malaria, especially aminoquinoline drugs-resistant strains of P.falciparum. We aim to carry out acute and subacute oral toxicity studies in rats to acquire preclinical data on the safety of AH. Acute toxicity was evaluated in Sprague-Dawley (SD) rats at a single dose of 1980, 2970, 4450, 6670, and 10000 mg/kg. A 14-days subacute toxicity was assessed in SD rats at doses of 0, 146, 219, 328, and 429 mg/kg. The median lethal dose (LD₅₀) of acute oral administration of AH in rats is found to be 3119 mg/kg, and toxic symptoms include decreased spontaneous activity, dyspnea, bristling, soft feces, spasticity, and convulsion. Repeated doses of AH have toxic effects on the nervous system, skin, blood system, liver, kidney, and spleen in rats. The main toxic reactions include epilation, emaciation, mental irritability, decreased body weight gain and food consumption, changes in the hematological and biochemical parameters, especially pathological lesions in the liver, kidney, and spleen. The no-observed-adverse-effect level (NOAEL) and lowest-observed-adverse-effect level (LOAEL) of AH are considered to be 219 mg/kg and 328 mg/kg, respectively.

Artemisinin displays bactericidal activity via copper-mediated DNA damage

Artemisinin (ARS) and its semi-synthetic derivatives are effective drugs to treat malaria and possess multiple therapeutic activities based on their endoperoxide bridge. Here, we showed that ARS displayed antibacterial efficacy in Drosophila systemic infections caused by bacterial pathogens but killed only Vibrio cholerae (VC) in vitro, involving reactive oxygen species (ROS) generation and/or DNA damage. This selective antibacterial activity of ARS was attributed to the higher intracellular copper levels in VC, in that the antibacterial activity was observed in vitro upon addition of cuprous ions even against other bacteria and was compromised by the copper-specific chelators neocuproine (NC) and triethylenetetramine (TETA) in vitro and in vivo. We suggest that copper can enhance or reinforce the therapeutic activities of ARS to be repurposed as an antibacterial drug for the treatment of bacterial infections.

Efficacy of artemisinin and its derivatives in animal models of type 2 diabetes mellitus: A systematic review and meta-analysis

Although current evidence suggests that artemisinin and its derivatives play a multitarget therapeutic role in type 2 diabetes mellitus (T2DM), their efficacy and safety remain under debate. This meta-analysis aimed to evaluate the effects and safety of artemisinin and its derivatives in T2DM animal models. Preclinical studies that met the inclusion criteria were retrieved from PubMed, Embase, Web of Science, Scopus, CINAHL, OpenGrey, Google Scholar, Psyclnfo, British Library Ethos, ProQuest Dissertations & Theses, China National Knowledge Internet, VIP Information Chinese Periodical Service Platform, Chinese Biomedicine Literature Database, and Wanfang Data Knowledge Service Platform. Twenty-two studies involving 526 animals were included in the meta-analysis. The RevMan 5.3 and Stata 15.0, were used to perform the statistical analyses. The overall results showed that artemisinin or its derivatives could significantly reduce fasting plasma glucose, 2-h plasma glucose (2hPG) in the intraperitoneal glucose tolerance test (IPGTT), 2hPG in the intraperitoneal insulin tolerance test (IPITT), glycated hemoglobin A1c, under the curve in the IPGTT/IPITT, total cholesterol, triglyceride, low-density lipoprotein cholesterol, free fatty acid, and urine volume. Although increase in body weight was observed due to administration of the compounds, no significant effect was observed regarding serum insulin. In terms of adverse reactions, only two of the included studies reported that high-dose artemether may cause digestive inhibition in mice. Our results suggest that artemisinins could improve several parameters related to glycolipid metabolism in T2DM animal models. However, to evaluate the antidiabetic effects and safety of artemisinins in a more accurate manner, additional preclinical studies are necessary.

Phytomedicine in Disease Management: In-Silico Analysis of the Binding Affinity of Artesunate and Azadirachtin for Malaria Treatment

In the rural communities of sub-Saharan African (sSA) countries, malaria is being managed using phytocompounds. Artesunate is reported to inhibit Gephyrin E, a central, multi-domain scaffolding protein of inhibitory post-synapses. Neem plant and its metabolites like azadirachtin are being indicated for management of malaria by traditional healers. The present study was aimed to cheminformatically analyse the binding potential of artesunate and azadirachtin with various reactive moieties of Gephyrin E, to reduce malaria scourge. With molecular dynamics (MD), binding free energy estimation and binding affinity of artesunate and azadirachtin to Gephyrin E was done. GRIP docking was done to study the interactions of these test ligands with Gephyrin E (6FGC). MD simulation gave insights to structural changes upon binding of artesunate and azadirachtin in the ligand-binding pocket of Gephyrin E. Root mean square deviation (RMSD) and root mean square fluctuation (RMSF) were calculated. From the estimation, azadirachtin had a total binding energy of -36.97 kcal/mol; artesunate had a binding energy of -35.73 kcal/mol. The GRIP docking results provided a clearer evidence that artesunate has comparatively better binding affinity to Gephyrin E than azadirachtin, and the critical binding sites (in activity order) were cavity 3, 2, 8, and 6 for artesunate while for azadirachtin, it was cavity 6, 3, 8, and 2. The GRIP docking provided detailed interactions at the atomic levels, providing evidence; both compounds have chances to overcome the drug resistance problem, albeit higher for artesunate. Our findings added another piece of evidence that azadirachtin may be effective as an anti-malarial agent. The results herein may provide impetus for more studies into bioactive components of plant origin towards the effective management of malaria disease phenotype.

NADPH Oxidase: a Possible Therapeutic Target for Cognitive Impairment in Experimental Cerebral Malaria

Long-term cognitive impairment associated with seizure-induced hippocampal damage is the key feature of cerebral malaria (CM) pathogenesis. One-fourth of child survivors of CM suffer from long-lasting neurological deficits and behavioral anomalies. However, mechanisms on hippocampal dysfunction are unclear. In this study, we elucidated whether gp91^phox isoform of nicotinamide adenine dinucleotide phosphate oxidase 2 (NOX2) (a potent marker of oxidative stress) mediates hippocampal neuronal abnormalities and cognitive dysfunction in experimental CM (ECM). Mice symptomatic to CM were rescue treated with artemether monotherapy (ARM) and in combination with apocynin (ARM + APO) adjunctive based on scores of Rapid Murine Come behavior Scale (RMCBS). After a 30-day survivability period, we performed Barnes maze, T-maze, and novel object recognition cognitive tests to evaluate working and reference memory in all the experimental groups except CM. Sensorimotor tests were conducted in all the cohorts to assess motor coordination. We performed Golgi-Cox staining to illustrate cornu ammonis-1 (CA1) pyramidal neuronal morphology and study overall hippocampal neuronal density changes. Further, expression of NOX2, NeuN (neuronal marker) in hippocampal CA1 and dentate gyrus was determined using double immunofluorescence experiments in all the experimental groups. Mice administered with ARM monotherapy and APO adjunctive treatment exhibited similar survivability. The latter showed better locomotor and cognitive functions, reduced ROS levels, and hippocampal NOX2 immunoreactivity in ECM. Our results show a substantial increase in hippocampal NeuN immunoreactivity and dendritic arborization in ARM + APO cohorts compared to ARM-treated brain samples. Overall, our study suggests that overexpression of NOX2 could result in loss of hippocampal neuronal density and dendritic spines of CA1 neurons affecting the spatial working and reference memory during ECM. Notably, ARM + APO adjunctive therapy reversed the altered neuronal morphology and oxidative damage in hippocampal neurons restoring long-term cognitive functions after CM.

Intravenous Artesunate for the Treatment of Severe Imported Malaria: Implementation, Efficacy, and Safety in 1391 Patients

BACKGROUND

Intravenous artesunate is the World Health Organization-recommended first-line treatment for severe malaria worldwide, but it is still not fully licensed in Europe. Observational studies documenting its safety and efficacy in imported malaria are thus essential.

METHODS

We prospectively collected clinical and epidemiological features of 1391 artesunate-treated patients among 110 participant centers during the first 7 years (2011-2017) of a national program implemented by the French Drug Agency.

RESULTS

Artesunate became the most frequent treatment for severe malaria in France, rising from 9.9% in 2011 to 71.4% in 2017. Mortality was estimated at 4.1%. Treatment failure was recorded in 27 patients, but mutations in the Kelch-13 gene were not observed. Main reported adverse events (AEs) were anemia (136 cases), cardiac events (24, including 20 episodes of conduction disorders and/or arrhythmia), and liver enzyme elevation (23). Mortality and AEs were similar in the general population and in people with human immunodeficiency virus, who were overweight, or were pregnant, but the only pregnant woman treated in the first trimester experimented a hemorrhagic miscarriage. The incidence of post-artesunate-delayed hemolysis (PADH) was 42.8% when specifically assessed in a 98-patient subgroup, but was not associated with fatal outcomes or sequelae. PADH was twice as frequent in patients of European compared with African origin.

CONCLUSIONS

Artesunate was rapidly deployed and displayed a robust clinical benefit in patients with severe imported malaria, despite a high frequency of mild to moderate PADH. Further explorations in the context of importation should assess outcomes during the first trimester of pregnancy and collect rare but potentially severe cardiac AEs.

Effect of Artemisia extract on glycemic control: A systematic review and meta-analysis of randomized controlled trial

BACKGROUND AND AIM

Animal and human studies have indicated anti-diabetic effect of Asteraceae. The present study aimed to systematically review and analyse randomized controlled trials assessing the effect of Artemisia extract on glycemic status in patients with impaired glycemic control.

METHODS

Web of Science, Cochrane library, EMBASE and PubMed databases were searched from the earliest possible date up to 7th October 2020.

RESULTS

Six studies were included in the meta-analysis. Analysis showed that supplementation with Artemisia extract decreased homeostatic model assessment of insulin resistance (HOMA-IR) (-0.734, 95% CI: -1.236 to -0.232, P = .019) in comparison to placebo. However, reductions in fasting blood glucose (FBG) (-0.595, 95% CI: -1.566 to 0.376, P = .164), insulin (-0.322, 95% CI: -1.047 to 0.404, P = .286) and glycated haemoglobin (-0.106, 95% CI: -0.840 to 0.629, P = .678) were not statistically significant.

CONCLUSION

Supplementation with Artemisia extract may reduce HOMA-IR, but beneficial effects on other markers such as FBG requires further investigations.

Anticoccidial Activity of Qinghao Powder Against Eimeria tenella in Broiler Chickens

Artemisia annua (AAH) is traditionally used as an anti-malarial, expectorant and antipyretic Chinese medicine. The aim of this study was to explore the therapeutic effect of Qinghao Powder (QHP) on chicken coccidiosis, evaluate the safe dosage of QHP, and provide test basis for clinical medication. High-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC) were used to detect artemisinin in Qinghao Powder (QHP) for quality control. The level of artemisinin in QHP was 81.03 mg/g. A total of 210 chicks (14 days of age) were divided randomly into seven groups: three QHP treatments (0.15, 0.30, and 0.60 g/kg), a toltrazuril control (1.00 mL/L), a sulfachloropyrazine sodium control (SSC, 0.30 g/L), an E. tenella-infected control, and a healthy control group. All the groups were inoculated orally with 7 × 10⁴E. tenella oocysts except for the healthy control group. After seven days of administration, compared with the infected control group, chicks which were administered QHP, SS, and toltrazuril showed less bloody feces, oocyst output, and cecal lesions, and the protection rates were improved. The maximum rBWG and ACI were found in the SS-medicated group, followed by the groups medicated with 0.60 and 0.30 g/kg QHP. Therefore, a 0.30 g/kg dose level of QHP in the feed was selected as the recommend dose (RD) in the target animal safety test, in which 80 broiler chicks (14 days of age) were randomly divided into four major groups (I-healthy control group; II-1× RD; III-3× RD; IV-6× RD), with each group subdivided into two subgroups (A and B) consisting of 10 chicks each. After 7-day (for sub-group A) or 14-day (for sub-group B) administration, compared with the healthy control, treatment-related changes in BWG, feed conversion ratio (FCR), relative organ weight (ROW) of the liver, WBC counts, and levels of RBC, HGB, ALT, AST, and TBIL were detected in the 3× and 6× RD groups. No differences were noted in necropsy for all doses, and histopathological examinations exhibited no QHP-associated signs of toxicity or abnormalities in the liver or kidney. The findings suggest that QHP at a dose of 0.30 g/kg feed would be appropriate for therapy and intermittent treatment of E. tenella-infected chicks, the dosage in clinical applications should be set according to the recommended dose to ensure animal safety.

Inhibitory Effect of Dihydroartemisinin on the Proliferation and Migration of Melanoma Cells and Experimental Lung Metastasis From Melanoma in Mice

Melanoma is aggressive and can metastasize in the early stage of tumor. It has been proved that dihydroartemisinin (DHA) positively affects the treatment of tumors and has no apparent toxic and side effects. Our previous research has shown that DHA can suppress the formation of melanoma. However, it remains poorly established how DHA impacts the invasion and metastasis of melanoma. In this study, B16F10 and A375 cell lines and metastatic tumor models will be used to investigate the effects of DHA. The present results demonstrated that DHA inhibited the proliferative capacity in A375 and B16F10 cells. As expected, the migration capacity of A375 and B16F10 cells was also reduced after DHA administration. DHA alleviated the severity and histopathological changes of melanoma in mice. DHA induced expansion of CD8⁺CTL in the tumor microenvironment. By contrast, DHA inhibited Treg cells infiltration into the tumor microenvironment. DHA enhanced apoptosis of melanoma by regulating FasL expression and Granzyme B secretion in CD8⁺CTLs. Moreover, DHA impacts STAT3-induced EMT and MMP_S in tumor tissue. Furthermore, Metabolomics analysis indicated that PGD2 and EPA significantly increased after DHA administration. In conclusion, DHA inhibited the proliferation, migration and metastasis of melanoma in vitro and in vivo. These results have important implications for the potential use of DHA in the treatment of melanoma in humans.

Computational approach towards the design of artemisinin-thymoquinone hybrids against main protease of SARS-COV-2

Background

The sanitary emergency installed in the world, generated by the pandemic of COVID-19, instigates the search for scientific strategies to mitigate the damage caused by the disease to different sectors of society. The disease caused by the coronavirus, SARS-CoV-2, reached 216 countries/territories, where about 199 million people were reported with the infection. Of these, more than 4 million died. In this sense, strategies involving the development of new antiviral molecules are extremely important. The main protease (Mpro) from SARS-CoV-2 is an important target, which has been widely studied for antiviral treatment. This work aims to perform a screening of pharmacodynamics and pharmacokinetics of synthetic hybrids from thymoquinone and artemisin (THY-ART) against COVID-19.

Results

Molecular docking studies indicated that hybrids of artemisinin and thymoquinone showed a relevant interaction with the active fraction of the enzyme Mpro, when compared to the reference drugs. Furthermore, hybrids show an improvement in the interaction of substances with the enzyme, mainly due to the higher frequency of interactions with the Thr199 residue. ADMET studies indicated that hybrids tend to permeate biological membranes, allowing good human intestinal absorption, with low partition to the central nervous system, potentiation for CYP-450 enzyme inhibitors, low risk of toxicity compared to commercially available drugs, considering mainly mutagenicity and cardiotoxicity, low capacity of hybrids to permeate the blood–brain barrier, high absorption and moderate permeability in Caco-2 cells. In addition, T1–T7 tend to have a better distribution of their available fractions to carry out diffusion and transport across cell membranes, as well as increase the energy of interaction with the SARS-CoV-2 target.

Conclusions

Hybrid products of artemisinin and thymoquinone have the potential to inhibit Mpro, with desirable pharmacokinetic and toxicity characteristics compared to commercially available drugs, being indicated for preclinical and subsequent clinical studies against SARS-CoV-2. Emphasizing the possibility of synergistic use with currently used drugs in order to increase half-life and generate a possible synergistic effect. This work represents an important step for the development of specific drugs against COVID-19.

Anti-malarial drug: the emerging role of artemisinin and its derivatives in liver disease treatment

Artemisinin and its derivatives belong to a family of drugs approved for the treatment of malaria with known clinical safety and efficacy. In addition to its anti-malarial effect, artemisinin displays anti-viral, anti-inflammatory, and anti-cancer effects in vivo and in vitro. Recently, much attention has been paid to the therapeutic role of artemisinin in liver diseases. Several studies suggest that artemisinin and its derivatives can protect the liver through different mechanisms, such as those pertaining to inflammation, proliferation, invasion, metastasis, and induction of apoptosis and autophagy. In this review, we provide a comprehensive discussion of the underlying molecular mechanisms and signaling pathways of artemisinin and its derivatives in treating liver diseases. Further pharmacological research will aid in determining whether artemisinin and its derivatives may serve as promising medicines for the treatment of liver diseases in the future.

Antimalarial drug discovery: from quinine to the most recent promising clinical drug candidates

Malaria is a tropical threatening disease caused by Plasmodium parasites, resulting in 409,000 deaths in 2019. The delay of mortality and morbidity has been compounded by the widespread of drug resistant parasites from Southeast Asia since two decades. The emergence of artemisinin-resistant Plasmodium in Africa, where most cases are accounted, highlights the urgent need for new medicines. In this effort, the World Health Organization and Medicines for Malaria Venture joined to define clear goals for novel therapies and characterized the target candidate profile. This ongoing search for new treatments is based on imperative labor in medicinal chemistry which is summarized here with particular attention to hit-to-lead optimizations, key properties, and modes of action of these novel antimalarial drugs. This review, after presenting the current antimalarial chemotherapy, from quinine to the latest marketed drugs, focuses in particular on recent advances of the most promising antimalarial candidates in clinical and preclinical phases.

Advanced and Innovative Nano-Systems for Anticancer Targeted Drug Delivery

The encapsulation of therapeutic agents into nano-based drug delivery system for cancer treatment has received considerable attention in recent years. Advancements in nanotechnology provide an opportunity for efficient delivery of anticancer drugs. The unique properties of nanoparticles not only allow cancer-specific drug delivery by inherent passive targeting phenomena and adopting active targeting strategies, but also improve the pharmacokinetics and bioavailability of the loaded drugs, leading to enhanced therapeutic efficacy and safety compared to conventional treatment modalities. Small molecule drugs are the most widely used anticancer agents at present, while biological macromolecules, such as therapeutic antibodies, peptides and genes, have gained increasing attention. Therefore, this review focuses on the recent achievements of novel nano-encapsulation in targeted drug delivery. A comprehensive introduction of intelligent delivery strategies based on various nanocarriers to encapsulate small molecule chemotherapeutic drugs and biological macromolecule drugs in cancer treatment will also be highlighted.

The immunosuppressive activity of artemisinin-type drugs towards inflammatory and autoimmune diseases

The sesquiterpene lactone artemisinin from Artemisia annua L. is well established for malaria therapy, but its bioactivity spectrum is much broader. In this review, we give a comprehensive and timely overview of the literature regarding the immunosuppressive activity of artemisinin-type compounds toward inflammatory and autoimmune diseases. Numerous receptor-coupled signaling pathways are inhibited by artemisinins, including the receptors for interleukin-1 (IL-1), tumor necrosis factor-α (TNF-α), β3-integrin, or RANKL, toll-like receptors and growth factor receptors. Among the receptor-coupled signal transducers are extracellular signal-regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), AKT serine/threonine kinase (AKT), mitogen-activated protein kinase (MAPK)/extracellular signal regulated kinase (ERK) kinase (MEK), phospholipase C γ1 (PLCγ), and others. All these receptors and signal transduction molecules are known to contribute to the inhibition of the transcription factor nuclear factor κ B (NF-κB). Artemisinins may inhibit NF-κB by silencing these upstream pathways and/or by direct binding to NF-κB. Numerous NF-κB-regulated downstream genes are downregulated by artemisinin and its derivatives, for example, cytokines, chemokines, and immune receptors, which regulate immune cell differentiation, apoptosis genes, proliferation-regulating genes, signal transducers, and genes involved in antioxidant stress response. In addition to the prominent role of NF-κB, other transcription factors are also inhibited by artemisinins (mammalian target of rapamycin [mTOR], activating protein 1 [AP1]/FBJ murine osteosarcoma viral oncogene homologue [FOS]/JUN oncogenic transcription factor [JUN]), hypoxia-induced factor 1α (HIF-1α), nuclear factor of activated T cells c1 (NF-ATC1), Signal transducers and activators of transcription (STAT), NF E2-related factor-2 (NRF-2), retinoic-acid-receptor-related orphan nuclear receptor γ (ROR-γt), and forkhead box P-3 (FOXP-3). Many in vivo experiments in disease-relevant animal models demonstrate therapeutic efficacy of artemisinin-type drugs against rheumatic diseases (rheumatoid arthritis, osteoarthritis, lupus erythematosus, arthrosis, and gout), lung diseases (asthma, acute lung injury, and pulmonary fibrosis), neurological diseases (autoimmune encephalitis, Alzheimer's disease, and myasthenia gravis), skin diseases (dermatitis, rosacea, and psoriasis), inflammatory bowel disease, and other inflammatory and autoimmune diseases. Randomized clinical trials should be conducted in the future to translate the plethora of preclinical results into clinical practice.

Toward New Transmission-Blocking Combination Therapies: Pharmacokinetics of 10-Amino-Artemisinins and 11-Aza-Artemisinin and Comparison with Dihydroartemisinin and Artemether

As artemisinin combination therapies (ACTs) are compromised by resistance, we are evaluating triple combination therapies (TACTs) comprising an amino-artemisinin, a redox drug, and a third drug with a different mode of action. Thus, here we briefly review efficacy data on artemisone, artemiside, other amino-artemisinins, and 11-aza-artemisinin and conduct absorption, distribution, and metabolism and excretion (ADME) profiling in vitro and pharmacokinetic (PK) profiling in vivo via intravenous (i.v.) and oral (p.o.) administration to mice. The sulfamide derivative has a notably long murine microsomal half-life (t1/2 > 150 min), low intrinsic liver clearance and total plasma clearance rates (CLint 189.4, CLtot 32.2 ml/min/kg), and high relative bioavailability (F = 59%). Kinetics are somewhat similar for 11-aza-artemisinin (t1/2 > 150 min, CLint = 576.9, CLtot = 75.0 ml/min/kg), although bioavailability is lower (F = 14%). In contrast, artemether is rapidly metabolized to dihydroartemisinin (DHA) (t1/2 = 17.4 min) and eliminated (CLint = 855.0, CLtot = 119.7 ml/min/kg) and has low oral bioavailability (F) of 2%. While artemisone displays low t1/2 of <10 min and high CLint of 302.1, it displays a low CLtot of 42.3 ml/min/kg and moderate bioavailability (F) of 32%. Its active metabolite M1 displays a much-improved t1/2 of >150 min and a reduced CLint of 37.4 ml/min/kg. Artemiside has t1/2 of 12.4 min, CLint of 673.9, and CLtot of 129.7 ml/kg/min, likely a reflection of its surprisingly rapid metabolism to artemisone, reported here for the first time. DHA is not formed from any amino-artemisinin. Overall, the efficacy and PK data strongly support the development of selected amino-artemisinins as components of new TACTs.

Recent pharmacological advances in the repurposing of artemisinin drugs

Artemisinins are a family of sesquiterpene lactones originally derived from the sweet wormwood (Artemisia annua). Beyond their well-characterized role as frontline antimalarial drugs, artemisinins have also received increased attention for other potential pharmaceutical effects, which include antiviral, antiparsitic, antifungal, anti-inflammatory, and anticancer activities. With concerted efforts in further preclinical and clinical studies, artemisinin-based drugs have the potential to be viable treatments for a great variety of human diseases. Here, we provide a comprehensive update on recent reports of pharmacological actions and applications of artemisinins outside of their better-known antimalarial role and highlight their potential therapeutic viability for various diseases.

Ototoxic hearing loss from antimalarials: A systematic narrative review

BACKGROUND

Drugs used in curative and prophylactic antimalarial treatment may be ototoxic and lead to permanent hearing loss, but there is no consensus regarding prevalence and permanence of ototoxic hearing loss caused by antimalarials. The purpose of this systematic narrative review was to synthesize current evidence on antimalarial ototoxicity in human populations.

METHOD

Studies published between 2005 and 2018 that reported prevalence of post-treatment hearing loss in individuals treated for malaria were included.

RESULTS

Twenty-two studies including data from 21 countries were included. Primary themes of the included studies were to evaluate drug safety and/or efficacy (n = 13) or ototoxic effects of drugs (n = 9). Hearing data were measured objectively in 9 studies. Five studies focused on quinine (or derivates), 10 focused on artemisinin combination therapies, and 7 considered multiple drug combinations. There is a paucity of evidence that thoroughly reports potentially permanent ototoxic effects of antimalarials.

CONCLUSIONS

Antimalarial drugs may be ototoxic in some cases. More research in human populations is needed to describe ototoxicity of current antimalarials and of future drugs that will be used/developed in response to antimalarial resistance. It is recommended that randomized trials evaluating drug safety objectively measure and report ototoxic hearing loss as an adverse event.

Selection of safe artemisinin derivatives using a machine learning-based cardiotoxicity platform and in vitro and in vivo validation

The majority of drug candidates fails the approval phase due to unwanted toxicities and side effects. Establishment of an effective toxicity prediction platform is of utmost importance, to increase the efficiency of the drug discovery process. For this purpose, we developed a toxicity prediction platform with machine-learning strategies. Cardiotoxicity prediction was performed by establishing a model with five parameters (arrhythmia, cardiac failure, heart block, hypertension, myocardial infarction) and additional toxicity predictions such as hepatotoxicity, reproductive toxicity, mutagenicity, and tumorigenicity are performed by using Data Warrior and Pro-Tox-II software. As a case study, we selected artemisinin derivatives to evaluate the platform and to provide a list of safe artemisinin derivatives. Artemisinin from Artemisia annua was described first as an anti-malarial compound and later its anticancer properties were discovered. Here, random forest feature selection algorithm was used for the establishment of cardiotoxicity models. High AUC scores above 0.830 were achieved for all five cardiotoxicity indications. Using a chemical library of 374 artemisinin derivatives as a case study, 7 compounds (deoxydihydro-artemisinin, 3-hydroxy-deoxy-dihydroartemisinin, 3-desoxy-dihydroartemisinin, dihydroartemisinin-furano acetate-d3, deoxyartemisinin, artemisinin G, artemisinin B) passed the toxicity filtering process for hepatotoxicity, mutagenicity, tumorigenicity, and reproductive toxicity in addition to cardiotoxicity. Experimental validation with the cardiomyocyte cell line AC16 supported the findings from the in silico cardiotoxicity model predictions. Transcriptomic profiling of AC16 cells upon artemisinin B treatment revealed a similar gene expression profile as that of the control compound, dexrazoxane. In vivo experiments with a Zebrafish model further substantiated the in silico and in vitro data, as only slight cardiotoxicity in picomolar range was observed. In conclusion, our machine-learning approach combined with in vitro and in vivo experimentation represents a suitable method to predict cardiotoxicity of drug candidates.

Defective palmitoylation of transferrin receptor triggers iron overload in Friedreich ataxia fibroblasts

Friedreich ataxia (FRDA) is a frequent autosomal recessive disease caused by a GAA repeat expansion in the FXN gene encoding frataxin, a mitochondrial protein involved in iron-sulfur cluster (ISC) biogenesis. Resulting frataxin deficiency affects ISC-containing proteins and causes iron to accumulate in the brain and heart of FRDA patients. Here we report on abnormal cellular iron homeostasis in FRDA fibroblasts inducing a massive iron overload in cytosol and mitochondria. We observe membrane transferrin receptor 1 (TfR1) accumulation, increased TfR1 endocytosis, and delayed Tf recycling, ascribing this to impaired TfR1 palmitoylation. Frataxin deficiency is shown to reduce coenzyme A (CoA) availability for TfR1 palmitoylation. Finally, we demonstrate that artesunate, CoA, and dichloroacetate improve TfR1 palmitoylation and decrease iron overload, paving the road for evidence-based therapeutic strategies at the actionable level of TfR1 palmitoylation in FRDA.

Artemisinin attenuated oxidative stress and apoptosis by inhibiting autophagy in MPP+-treated SH-SY5Y cells

BACKGROUND

Parkinson's disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease. The oxidative stress is an important component of the pathogenesis of PD. Artemisinin (ART) has antioxidant and neuroprotective effects. The purpose of this study is to explore the neuroprotective effect of ART on 1-methyl-4-phenyliodine iodide (MPP ⁺)-treated SH-SY5Y cells and underlying mechanism.

METHODS

We used MPP⁺-treated SH-SY5Y cells to study the neuroprotective effect of ART. Cell viability was measured by MTT assay after incubating the cells with MPP⁺ and/or ART for 24 h. DCFH-DA was used to detect the level of intracellular reactive oxygen species (ROS), and WST-8 was used to detect the level of superoxide dismutase (SOD). The level of intracellular reduced glutathione (GSH) was detected with 5,5΄-dithiobis-(2-nitrobenzoic acid), and the level of malondialdehyde (MDA) was assessed based on the reaction of MDA and thiobarbituric acid. A mitochondrial membrane potential detection kit (JC-1) was used to detect changes in the mitochondrial membrane potential (MMP), and an Annexin V-FITC cell apoptosis kit was used to detect cell apoptosis. The expression levels of caspase-3, cleaved caspase-3 and the autophagy-related proteins LC3, beclin-1, and p62 were detected by Western blotting. In addition, to verify the change in autophagy, we used immunofluorescence to detect the expression of LC3 and p62.

RESULTS

No significant cytotoxicity was observed at ART concentrations up to 40 μM. ART could significantly increase the viability of SH-SY5Y cells treated with MPP⁺ and reduce oxidative stress damage and apoptosis. In addition, the Western blotting and immunofluorescence results showed that MPP⁺ treatment could increase the protein expression of beclin1 and LC3II/LC3I and decrease the protein expression of p62, indicating that MPP⁺ treatment could induce autophagy. Simultaneous treatment with ART and MPP⁺ could decrease the protein expression of beclin1 and LC3II/LC3I and increase the protein expression of p62, indicating that ART could decrease the level of autophagy induced by MPP⁺.

CONCLUSION

Our results indicate that ART has a protective effect on MPP⁺-treated SH-SY5Y cells by the antioxidant, antiapoptotic activities and inhibition of autophagy. Our findings may provide new hope for the prevention and treatment of PD.

Predicting the Disposition of the Antimalarial Drug Artesunate and Its Active Metabolite Dihydroartemisinin Using Physiologically Based Pharmacokinetic Modeling

Artemisinin-based combination therapies (ACTs) have proven to be effective in helping to combat the global malaria epidemic. To optimally apply these drugs, information about their tissue-specific disposition is required, and one approach to predict these pharmacokinetic characteristics is physiologically based pharmacokinetic (PBPK) modeling. In this study, a whole-body PBPK model was developed to simulate the time-dependent tissue concentrations of artesunate (AS) and its active metabolite, dihydroartemisinin (DHA). The model was developed for both rats and humans and incorporated drug metabolism of the parent compound and major metabolite. Model calibration was conducted using data from the literature in a Bayesian framework, and model verification was assessed using separate sets of data. Results showed good agreement between model predictions and the validation data, demonstrating the capability of the model in predicting the blood, plasma, and tissue pharmacokinetics of AS and DHA. It is expected that such a tool will be useful in characterizing the disposition of these chemicals and ultimately improve dosing regimens by enabling a quantitative assessment of the tissue-specific drug levels critical in the evaluation of efficacy and toxicity.