Exploring the neuroprotective role of artesunate in mouse models of anti-NMDAR encephalitis: insights from molecular mechanisms and transmission electron microscopy.

BACKGROUND: The pathway involving PTEN-induced putative kinase 1 (PINK1) and PARKIN plays a crucial role in mitophagy, a process activated by artesunate (ART). We propose that patients with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis exhibit insufficient mitophagy, and ART enhances mitophagy via the PINK1/PARKIN pathway, thereby providing neuroprotection. METHODS: Adult female mice aged 8-10 weeks were selected to create a passive transfer model of anti-NMDAR encephalitis. We conducted behavioral tests on these mice within a set timeframe. Techniques such as immunohistochemistry, immunofluorescence, and western blotting were employed to assess markers including PINK1, PARKIN, LC3B, p62, caspase3, and cleaved caspase3. The TUNEL assay was utilized to detect neuronal apoptosis, while transmission electron microscopy (TEM) was used to examine mitochondrial autophagosomes. Primary hippocampal neurons were cultured, treated, and then analyzed through immunofluorescence for mtDNA, mtROS, TMRM. RESULTS: In comparison to the control group, mitophagy levels in the experimental group were not significantly altered, yet there was a notable increase in apoptotic neurons. Furthermore, markers indicative of mitochondrial leakage and damage were found to be elevated in the experimental group compared to the control group, but these markers showed improvement following ART treatment. ART was effective in activating the PINK1/PARKIN pathway, enhancing mitophagy, and diminishing neuronal apoptosis. Behavioral assessments revealed that ART ameliorated symptoms in mice with anti-NMDAR encephalitis in the passive transfer model (PTM). The knockdown of PINK1 led to a reduction in mitophagy levels, and subsequent ART intervention did not alleviate symptoms in the anti-NMDAR encephalitis PTM mice, indicating that ART's therapeutic efficacy is mediated through the activation of the PINK1/PARKIN pathway. CONCLUSIONS: At the onset of anti-NMDAR encephalitis, mitochondrial damage is observed; however, this damage is mitigated by the activation of mitophagy via the PINK1/PARKIN pathway. This regulatory feedback mechanism facilitates the removal of damaged mitochondria, prevents neuronal apoptosis, and consequently safeguards neural tissue. ART activates the PINK1/PARKIN pathway to enhance mitophagy, thereby exerting neuroprotective effects and may achieve therapeutic goals in treating anti-NMDAR encephalitis.

Differential Anti-Fibrotic and Remodeling Responses of Human Dermal Fibroblasts to Artemisia sp., Artemisinin, and Its Derivatives.

Fibrosis is a ubiquitous pathology, and prior studies have indicated that various artemisinin (ART) derivatives (including artesunate (AS), artemether (AM), and dihydroartemisinin (DHA)) can reduce fibrosis in vitro and in vivo. The medicinal plant Artemisia annua L. is the natural source of ART and is widely used, especially in underdeveloped countries, to treat a variety of diseases including malaria. A. afra contains no ART but is also antimalarial. Using human dermal fibroblasts (CRL-2097), we compared the effects of A. annua and A. afra tea infusions, ART, AS, AM, DHA, and a liver metabolite of ART, deoxyART (dART), on fibroblast viability and expression of key fibrotic marker genes after 1 and 4 days of treatment. AS, DHA, and Artemisia teas reduced fibroblast viability 4 d post-treatment in up to 80% of their respective controls. After 4 d of treatment, AS DHA and Artemisia teas downregulated ACTA2 up to 10 fold while ART had no significant effect, and AM increased viability by 10%. MMP1 and MMP3 were upregulated by AS, 17.5 and 32.6 fold, respectively, and by DHA, 8 and 51.8 fold, respectively. ART had no effect, but A. annua and A. afra teas increased MMP3 5 and 16-fold, respectively. Although A. afra tea increased COL3A1 5 fold, MMP1 decreased >7 fold with no change in either transcript by A. annua tea. Although A. annua contains ART, it had a significantly greater anti-fibrotic effect than ART alone but was less effective than A. afra. Immunofluorescent staining for smooth-muscle α-actin (α-SMA) correlated well with the transcriptional responses of drug-treated fibroblasts. Together, proliferation, qPCR, and immunofluorescence results show that treatment with ART, AS, DHA, and the two Artemisia teas yield differing responses, including those related to fibrosis, in human dermal fibroblasts, with evidence also of remodeling of fibrotic ECM.

Artesunate attenuates the tumorigenesis of choroidal melanoma via inhibiting EFNA3 through Stat3/Akt signaling pathway.

PURPOSE: Choroidal melanoma (CM), a kind of malignant tumor, is the main type of Uveal melanoma and one half of CM patients develop metastases. As a member of Eph/ephrin pathway that plays vital role in tumors, EphrinA3 (EFNA3) has been proved to promote tumorigenesis in many tumors. But the effect of EFNA3 in CM has not been studied yet. Through inhibiting angiogenesis, inducing apoptosis and autophagy and so on, Artesunate (ART) plays a key anti-tumor role in many tumors, including CM. However, the exact mechanisms of anti-tumor in CM remain unclear. METHODS: The UALCAN and TIMER v2.0 database analyzed the role of EFNA3 in CM patients. Quantitative real time polymerase chain reaction (qPCR) and Western blot were used to detect the expression of EFNA3 in CM. The growth ability of CM was tested by clonogenic assay and Cell counting kit-8 assay, and the migration ability using Transwell assay. RESULTS: Our results found EFNA3 boosted CM cells' growth and migration through activating Stat3/Akt signaling pathway, while ART inhibited the tumor promoting effect of CM via downregulating EFNA3. In xenograft tumor model, EFNA3 knockdown and ART significantly inhibited tumor growth. CONCLUSION: EFNA3 could be a valuable prognostic factor in CM.

Artesunate-loaded thermosensitive chitosan hydrogel promotes osteogenesis of maxillary tooth extraction through regulating T lymphocytes in type 2 diabetic rats.

BACKGROUND: Type 2 diabetes mellitus (T2DM) causes severe bone loss after tooth extraction as a hyperglycemic environment causes aberrant bone homeostasis. Artesunate (ART) is known to possess anti-inflammation and osteogenic properties. However, its osteogenesis property in alveolar bone remains unclear. This study aimed to explore the osteogenic and immunoregulatory effects of artesunate-loaded thermosensitive chitosan hydrogel (ART-loaded TCH) on maxilla tooth extraction in T2DM rats. METHODS: T2DM rats were induced by a high-fat diet and streptozotocin. Different concentrations of ART-loaded TCH were applied in tooth extraction sockets. Bone loss and the expression of osteogenic regulatory factors (OPG, ALP, RANK) were evaluated. The immunoregulatory effects of ART-loaded TCH were observed through detecting the infiltration of T lymphocytes and their cytokines. The underlying mechanisms were explored. RESULTS: Results showed that the 150 mg/ml ART-loaded TCH group significantly ameliorated maxilla bone height and bone mineral density when compared with the T2DM group (p < 0.05). It also improved the expression of OPG, ALP, and RANK. Although the alteration of CD4+ T, CD8+ T, and CD4+:CD8+ T ratio has no significant difference among groups, the release of Th1 and Th2 in the 150 mg/ml ART-loaded TCH group has been significantly regulated than in the T2DM group (p < 0.05). Besides, ART-loaded TCH treatment inhibited the expression of p38 MAPK and ERK1 in T2DM maxilla. CONCLUSIONS: Therefore, the results indicated that 150 mg/ml ART-loaded TCH could be an effective method to prevent bone loss in T2DM tooth extraction rats by modulating the immunoregulation of Th1 and Th2 and the MAPK signaling pathway.

Whole genome sequencing identifies novel mutations in malaria parasites resistant to artesunate (ATN) and to ATN + mefloquine combination.

Introduction: The global evolution of resistance to Artemisinin-based Combination Therapies (ACTs) by malaria parasites, will severely undermine our ability to control this devastating disease. Methods: Here, we have used whole genome sequencing to characterize the genetic variation in the experimentally evolved Plasmodium chabaudi parasite clone AS-ATNMF1, which is resistant to artesunate + mefloquine. Results and discussion: Five novel single nucleotide polymorphisms (SNPs) were identified, one of which was a previously undescribed E738K mutation in a 26S proteasome subunit that was selected for under artesunate pressure (in AS-ATN) and retained in AS-ATNMF1. The wild type and mutated three-dimensional (3D) structure models and molecular dynamics simulations of the P. falciparum 26S proteasome subunit Rpn2 suggested that the E738K mutation could change the toroidal proteasome/cyclosome domain organization and change the recognition of ubiquitinated proteins. The mutation in the 26S proteasome subunit may therefore contribute to altering oxidation-dependent ubiquitination of the MDR-1 and/or K13 proteins and/or other targets, resulting in changes in protein turnover. In light of the alarming increase in resistance to artemisin derivatives and ACT partner drugs in natural parasite populations, our results shed new light on the biology of resistance and provide information on novel molecular markers of resistance that may be tested (and potentially validated) in the field.

Anti-Opisthorchis felineus effects of artemisinin derivatives: An in vitro study.

BACKGROUND: The drug of choice for the treatment of opisthorchiasis caused by trematodes Opisthorchis viverrini and O. felineus is praziquantel (PZQ), but there is a constant search for new anthelmintics, including those of plant origin. Positive results on the use of artemisinin derivatives against O. viverrini opisthorchiasis have been shown previously, but the effect of these compounds on O. felineus has not been studied. Therefore, here, a comparative analysis of anthelmintic properties of artemisinin derivatives (artesunate [AS], artemether [AM], and dihydroartemisinin [DHA]) was carried out in vitro in relation to PZQ. Experiments were performed on newly excysted metacercariae (NEMs) and adult flukes of O. felineus. RESULTS: Dose- and time-dependent effects of artemisinin derivatives and of PZQ were assessed in terms of motility and mortality of both NEMs and adult flukes. The most pronounced anthelmintic action was exerted by DHA, whose half-maximal inhibitory concentrations (IC50) of 1.9 (NEMs) and 2.02 µg/mL (adult flukes) were lower than those of PZQ (0.56 and 0.25 µg/mL, respectively). In contrast to PZQ, the effects of DHA and AS were similar when we compared the two developmental stages of O. felineus (NEMs and adult flukes). In addition, AM, AS, and especially DHA at doses of 100 µg/mL disrupted tegument integrity in adult flukes, which was not observed with PZQ. CONCLUSIONS: Artemisinin derivatives (AS, AM, and DHA) have good anthelmintic efficacy against the trematode O. felineus, and the action of these substances is comparable to (and sometimes better than) the effects of PZQ.

Artesunate-loaded solid lipid nanoparticles resist esophageal squamous cell carcinoma by inducing Ferroptosis through inhibiting the AKT/mTOR signaling.

Esophageal squamous cell carcinoma (ESCC) is a severe malignancy with high incidence and mortality rate in China, while the application of standard chemotherapeutic drugs for ESCC meets the barriers of high toxicity and multiple drug resistance (MDR). In recent years, the anticancer effects of artesunate (ART), a Chinese medicine monomer have gained extensive attentions due to its characteristics of low toxicity, high potency, and reversal of MDR. In this study, we develop the artesunate-loaded solid lipid nanoparticles (SLNART) to overcome the poor water solubility and bioavailability of ART, further improving the efficiency of ART on ESCC treatment. Especially mentioned, SLNART is shown to present marked inhibitory effects on ESCC development based on the induction of ferroptosis by two pathways included upregulating TFR to increase Fe2+ ions and inhibiting the AKT/mTOR signaling to downregulate GPX4. Collectively, this study is the first to pave a promising approach for ESCC therapy based on a strategy of developing SLNART to induce ferroptosis by mediating Fe2+ ions and AKT/mTOR signaling.

Artesunate inhibits macrophage-like phenotype switching of vascular smooth muscle cells and attenuates vascular inflammatory injury in atherosclerosis via NLRP3.

Inflammation is one of the main pathogenic factors of atherosclerosis (AS), and the phenotypic transformation of macrophages in human vascular smooth muscle cells (HVSMCs) contributes to the inflammatory injury of blood vessels and the formation of atherosclerotic plaques. Artesunate reportedly exerts anti-inflammatory activity against AS. Herein, we aimed to explore the artesunate-mediated anti-inflammatory and HVSMC phenotypic switch effects against AS and elucidate potential underlying mechanisms. In vitro, artesunate decreased expression of NLRP3, caspase-1, and interleukin (IL)- 1ß. Artesunate significantly inhibited low-density lipoprotein (LDL) expression in HVSMCs and macrophages. In vivo, artesunate reduced atherosclerotic plaque formation in high-fat diet (HFD)-fed ApoE-/- mice, as well as decreased NLRP3 and CD68 expression in atherosclerotic plaques. Artesunate decreased serum levels of triglycerides and increased high-density lipoprotein levels in HFD-med mice; however, serum levels of total cholesterol and LDL were unaltered. Treatment with artesunate substantially increased α-smooth muscle actin expression in aortic tissues while inhibiting expression levels of NLRP3, IL-1ß, heparinase, matrix metalloproteinase 9, and Krüppel-like factor 4 (KLF4). Collectively, our findings suggest that artesunate-mediated effects may involve inhibition of the ERK1/2/NF-κB/IL-1ß pathway in HVSMCs via the downregulation of NLRP3 expression. Thus, artesunate could serve as a novel strategy to treat AS by inhibiting AS plaque formation and suppressing macrophage-like phenotype switching of HVSMCs.

Artesunate improves glucose and lipid metabolism in db/db mice by regulating the metabolic profile and the MAPK/PI3K/Akt signalling pathway.

BACKGROUND: Diabetes is a metabolic disorder characterized by chronic hyperglycaemia. Chronic metabolic abnormalities and long-term hyperglycaemia may result in a wide range of acute and chronic consequences. Previous studies have demonstrated that artesunate(ART) has antidiabetic, anti-inflammatory, antiatherosclerotic, and other beneficial effects, but the specific regulatory mechanism is not completely clear. AIM: This study investigated the effects of ART on metabolic disorders in type 2 diabetes mellitus (T2DM) model db/db mice and explored the underlying mechanisms involved. METHODS: C57BL/KsJ-db/db mice were used to identify the targets and molecular mechanism of ART. Metabolomic methods were used to evaluate the efficacy of ART in improving T2DM-related metabolic disorders. Network pharmacology and transcriptomic sequencing were used to analyse the targets and pathways of ART in T2DM. Finally, molecular biology experiments were performed to verify the key targets and pathways selected by network pharmacology and transcriptomic analyses. RESULTS: After a 7-week ART intervention (160 mg/kg), the glucose and lipid metabolism levels of the db/db mice improved. Additionally, the oxidative stress indices, namely, the MDA and SOD levels, significantly improved (p<0.01). Linoleic acid and glycerophospholipid metabolism, amino acid metabolism, bile acid synthesis, and purine metabolism disorders in db/db mice were partially corrected after ART treatment. Network pharmacology analysis identified important targets of ART for the treatment of metabolic disorders in T2DM . These targets are involved in key signalling pathways, including the highest scores observed for the PI3K/Akt signalling pathway. Transcriptomic analysis revealed that ART could activate the MAPK signalling pathway and two key gene targets, HGK and GADD45. Immunoblotting revealed that ART increases p-PI3K, p-AKT, Glut2, and IRS1 protein expression and suppresses the phosphorylation of p38, ERK1/2, and JNK, returning HGK and GADD45 to their preartesunate levels. CONCLUSION: Treatment of db/db mice with 160 mg/kg ART for 7 weeks significantly reduced fasting blood glucose and lipid levels. It also improved metabolic imbalances in amino acids, lipids, purines, and bile acids, thereby improving metabolic disorders. These effects are achieved by activating the PI3K/AKT pathway and inhibiting the MAPK pathway, thus demonstrating the efficacy of the drug.

Artesunate treats obesity in male mice and non-human primates through GDF15/GFRAL signalling axis.

Obesity, a global health challenge, is a major risk factor for multiple life-threatening diseases, including diabetes, fatty liver, and cancer. There is an ongoing need to identify safe and tolerable therapeutics for obesity management. Herein, we show that treatment with artesunate, an artemisinin derivative approved by the FDA for the treatment of severe malaria, effectively reduces body weight and improves metabolic profiles in preclinical models of obesity, including male mice with overnutrition-induced obesity and male cynomolgus macaques with spontaneous obesity, without inducing nausea and malaise. Artesunate promotes weight loss and reduces food intake in obese mice and cynomolgus macaques by increasing circulating levels of Growth Differentiation Factor 15 (GDF15), an appetite-regulating hormone with a brainstem-restricted receptor, the GDNF family receptor α-like (GFRAL). Mechanistically, artesunate induces the expression of GDF15 in multiple organs, especially the liver, in mice through a C/EBP homologous protein (CHOP)-directed integrated stress response. Inhibition of GDF15/GFRAL signalling by genetic ablation of GFRAL or tissue-specific knockdown of GDF15 abrogates the anti-obesity effect of artesunate in mice with diet-induced obesity, suggesting that artesunate controls bodyweight and appetite in a GDF15/GFRAL signalling-dependent manner. These data highlight the therapeutic benefits of artesunate in the treatment of obesity and related comorbidities.

Mesenchymal-epithelial transition and AXL inhibitor TP-0903 sensitise triple-negative breast cancer cells to the antimalarial compound, artesunate.

Triple-negative breast cancer (TNBC) is a difficult-to-treat, aggressive cancer type. TNBC is often associated with the cellular program of epithelial-mesenchymal transition (EMT) that confers drug resistance and metastasis. EMT and reverse mesenchymal-epithelial transition (MET) programs are regulated by several signaling pathways which converge on a group of transcription factors, EMT- TFs. Therapy approaches could rely on the EMT reversal to sensitise mesenchymal tumours to compounds effective against epithelial cancers. Here, we show that the antimalarial ROS-generating compound artesunate (ART) exhibits higher cytotoxicity in epithelial than mesenchymal breast cancer cell lines. Ectopic expression of EMT-TF ZEB1 in epithelial or ZEB1 depletion in mesenchymal cells, respectively, reduced or increased ART-generated ROS levels, DNA damage and apoptotic cell death. In epithelial cells, ZEB1 enhanced expression of superoxide dismutase 2 (SOD2) and glutathione peroxidase 8 (GPX8) implicated in ROS scavenging. Although SOD2 or GPX8 levels were unaffected in mesenchymal cells in response to ZEB1 depletion, stable ZEB1 knockdown enhanced total ROS. Receptor tyrosine kinase AXL maintains a mesenchymal phenotype and is overexpressed in TNBC. The clinically-relevant AXL inhibitor TP-0903 induced MET and synergised with ART to generate ROS, DNA damage and apoptosis in TNBC cells. TP-0903 reduced the expression of GPX8 and SOD2. Thus, TP-0903 and ZEB1 knockdown sensitised TNBC cells to ART, likely via different pathways. Synergistic interactions between TP-0903 and ART indicate that combination approaches involving these compounds can have therapeutic prospects for TNBC treatment.

Artesunate Sensitizes human hepatocellular carcinoma to sorafenib via exacerbating AFAP1L2-SRC-FUNDC1 axis-dependent mitophagy.

Sorafenib is the most widely used first-line drug for the treatment of the advanced hepatocellular carcinoma (HCC). Unfortunately, sorafenib resistance often limits its therapeutic efficacy. To evaluate the efficacy of artesunate against sorafenib-resistant HCC and to investigate its underlying pharmacological mechanisms, a "sorafenib resistance related gene-ART candidate target" interaction network was constructed, and a signaling axis consisting with artesunate candidate target AFAP1L2 and sorafenib target SRC, and the downstream FUNDC1-dependent mitophagy was identified as a major contributor to the sorafenib resistance and a potential way of artesunate to mitigate resistance. Notably, our clinical data demonstrated that AFAP1L2 expression in HCC tissues was markedly higher than that in adjacent non-cancerous liver tissues (P < 0.05), and high AFAP1L2 expression was also significantly associated with an unfavorable overall survival of HCC patients (P < 0.05). Experimentally, AFAP1L2 was overexpressed in sorafenib resistant cells, leading to the activation of downstream SRC-FUNDC1 signaling axis, further blocking the FUNDC1 recruitment of LC3B to mitochondria and inhibiting the activation of mitophagy, based on both in vitro and in vivo systems. Moreover, artesunate significantly enhanced the inhibitory effects of sorafenib on resistant cells and tumors by inducing excessive mitophagy. Mechanically, artesunate reduced the expression of AFAP1L2 protein, suppressed the phosphorylation levels of SRC and FUNDC1 proteins, promoted the FUNDC1 recruitment of massive LC3B to mitochondria, and further overactivated the mitophagy and subsequent cell apoptosis of sorafenib resistant cells. In conclusion, artesunate may be a promising strategy to mitigate sorafenib resistance in HCC via exacerbating AFAP1L2-SRC-FUNDC1 axis-dependent mitophagy.Abbreviations: AFAP1L2, actin filament associated protein 1 like 2; ANOVA, analysis of variance; ANXA5, annexin V; ART: artesunate; CETSA, cellular thermal shift assay; CI: combination index; CO-IP: co-immunoprecipitation; CQ: chloroquine; CT, computed tomography; [18F]-FDG, fluoro-2-D-deoxyglucose F18; FUNDC1: FUN14 domain containing 1; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; HCC, hepatocellular carcinoma; H&E Staining: hematoxylin - eosin staining; HepG2R, sorafenib resistant HepG2; IF, immunofluorescence; IHC, immunohistochemistry; LAMP1: lysosomal associated membrane protein 1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; miR, microRNA; mRNA: messenger RNA; OE, overexpression; OS, overall survival; PET, positron emission tomography; qRT-PCR: quantitative real-time PCR; sh, short hairpin; shNC: negative control shRNA; shAFAP1L2: short hairpin AFAP1L2; SORA, sorafenib; SPR, surface plasmon resonance; SRC, SRC proto-oncogene, non-receptor tyrosine kinase; SUV, standardized uptake value; TEM, transmission electron microscopy; TOMM20: translocase of outer mitochondrial membrane 20.

Chitosan-coated artesunate protects against ulcerative colitis via STAT6-mediated macrophage M2 polarization and intestinal barrier protection.

Oral delivery of chitosan-coated artesunate (CPA) has been proven to be effective at preventing ulcerative colitis (UC) in mice. However, the anti-inflammatory mechanism is not fully understood. STAT6 is a key transcription factor that promotes anti-inflammatory effects by inducing M2 and Th2 dominant phenotypes, therefore we hypothesized STAT6 might play a key role in the process. To prove it, a STAT6 gene knockout macrophage cell line (STAT6-/- RAW264.7, by CRISPR/Cas9 method), and its corresponding Caco-2/RAW264.7 co-culture system combined with the STAT6 inhibitor (AS1517499, AS) in a mouse UC model were established and studied. The results showed that CPA remarkably suppressed the activation of TLR-4/NF-κB pathway and the mRNA levels of proinflammatory cytokines, while increased the IL-10 levels in RAW264.7. This effect of CPA contributed to the protection of the ZO-1 in Caco-2 which was disrupted upon the stimulation to macrophages. Simultaneously, CPA reduced the expression of CD86 but increase the expression of CD206 and p-STAT6 in LPS-stimulated RAW264.7 cells. However, above alterations were not obvious as in STAT6-/- RAW264.7 and its co-culture system, suggesting STAT6 plays a key role. Furthermore, CPA treatment significantly inhibited TLR-4/NF-κB activation, intestinal macrophage M1 polarization and mucosal barrier injury induced by DSS while promoted STAT6 phosphorylation in the UC mouse model, but this effect was also prominently counteracted by AS. Therefore, our data indicate that STAT6 is a major regulator in the balance of M1/M2 polarization, intestinal barrier integrity and then anti-colitis effects of CPA. These findings broaden our understanding of how CPA fights against UC and imply an alternative treatment strategy for UC via this pathway.

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.

Artesunate attenuates serum amyloid A-induced M1 macrophage differentiation through the promotion of PHGDH.

Clinical studies indicated that Serum Amyloid A (SAA) might be a promising biomarker for forecasting the activity, severity, and adverse prognosis of systemic lupus erythematosus (SLE). Simultaneously, a positive correlation has been observed between macrophages, Th17 cells, and SLE disease activity, with both these immune cells being affected by SAA. Presently, the relationship between SAA and the aforementioned immune cell types in SLE remains to be elucidated. To discern the immune cell type most closely associated with SAA, we undertook a single-cell RNA sequencing data analysis via the GEO database. Subsequent results revealed a strong association between macrophages and SAA, a relationship further validated through flow cytometry of spleen macrophages in the MRL/lpr model. We discovered that SAA stimulate M1 macrophage differentiation along with the upregulation of pro-inflammatory cytokines such as IL-6 and IL-1ß. Our findings suggest that SAA may promote M1 macrophage differentiation via the downregulation of phosphoglycerate dehydrogenase (PHGDH). Artesunate (ART), primarily utilized for malaria treatment, was shown to inhibit M1 macrophage differentiation and pro-inflammatory cytokine levels via upregulating the PHGDH expression, thereby attenuating the disease activity in SLE.

Artesunate acts through cytochrome c to inhibit growth of pediatric AML cells.

Artesunate is a derivative of artemisinin, an active compound isolated from Artemisia annua which has been used in Traditional Chinese Medicine and to treat malaria worldwide. Artemisinin derivatives have exhibited anti-cancer activity against both solid tumors and leukemia. The direct target(s) of artesunate are controversial; although, heme-bound proteins in the mitochondria have been implicated. We utilized computational modeling to calculate the predicted binding score of artesunate with heme-bound mitochondrial proteins and identified cytochrome c as potential artesunate target. UV-visible spectroscopy showed changes in the absorbance spectrum, and thus protein structure, when cytochrome c was incubated with artesunate. Artesunate induces apoptosis, disrupts mitochondrial membrane potential, and is antagonized by methazolamide in pediatric AML cells indicating a probable mechanism of action involving cytochrome c. We utilized a multi-disciplinary approach to show that artesunate can interact with and is dependent on cytochrome c release to induce cell death in pediatric AML cell lines.

Artesunate reverses cytarabine resistance in acute myeloid leukemia by blocking the JAK/STAT3 signaling.

OBJECTIVES: Although cytarabine (AraC) has greatly contributed to improving the prognosis of patients with acute myeloid leukemia (AML), many patients developed drug resistance and eventually succumbed to AML. Thus, resistance to AraC is a major obstacle to improve the efficacy of chemotherapy in AML. Hence, this study aimed to demonstrate that artesunate (ART) can reliably induce cell death in vitro and block AraC resistance. METHODS: AML cell lines resistant to AraC were first constructed by repeated dosing for 5 months. Further, we analyzed whether ART intervention affected the sensitivity of AraC-resistant cells to AraC by cell function experiments, mainly including CCK-8 to assess cell viability, flow cytometry to examine apoptosis, and Western blotting to measure the Janus kinase (JAK)/signal transducers and activators of transcription 3 (STAT3) pathway protein expression. Furthermore, whether JAK/STAT3 pathway knockdown has a blocking effect on the efficacy of ART was also assessed. RESULTS: Co-treatment of ART and AraC increased the sensitivity of AML cells to AraC. Also, it effectively reversed the resistance of AML cells to AraC that is shown by the significantly reduced proliferation and increased apoptosis rates. ART intervention suppressed the activation of the JAK/STAT3 signaling pathway in AraC-resistant AML cells, suggesting that the function of ART in reversing AraC resistance is indeed dependent on the JAK/STAT3 signaling pathway. CONCLUSIONS: In summary, ART enhanced the sensitivity of AML/AraC-resistant cells to AraC by modulating the JAK/STAT3 pathway.

Artesunate induces ferroptosis by inhibiting the nuclear localization of SREBP2 in myeloma cells.

Objective: Multiple myeloma (MM) is an incurable haematological cancer characterized by abnormal proliferation of plasma cells. The promising therapeutic effect of selective inhibitors of nuclear export in MM reveals the broad therapeutic prospects of nuclear localization intervention. Sterol regulatory element binding protein 2 (SREBP2) is a lipid regulatory molecule that has been implicated in the effect of drug therapy for MM. SREBP2 has been reported to be regulated by the antimalarial drug artesunate (ART) through alteration of its nuclear localization and has been shown to inhibit ferroptosis in other tumours. However, the mechanism through which this might occur has not been clarified in MM. Our study aimed to explore whether ART can induce ferroptosis in MM through nuclear localization of SREBP2. Methods: To evaluate whether ferroptosis is induced by treatment with ART in myeloma, we used two types of myeloma cell lines. We first used a series of molecular approaches and other techniques to investigate the impact of ART on cell growth, production of reactive oxygen species (ROS), Fe2+ levels, lipid peroxidation and expression of genes related to ferroptosis. Then, we further explored the mechanism through which ferroptosis may occur in these cells and the relationship between ferroptosis and the nuclear localization of SREBP2. Results: Upregulation of ROS, Fe2+, and lipid peroxidation as well as inhibition of cell growth were observed in myeloma cells after treatment with ART. Expression of acyl CoA synthase long chain family member 4 (ACSL4) was increased, while glutathione peroxidase 4 (GPX4) expression was reduced in cells treated with ART. ART-induced cell death could be reversed by ferropstatin-1 (Fer-1) and deferoxamine mesylate (DFO). Nuclear localization of SREBP2 in myeloma cells was inhibited, accompanied by downregulation of isopentenyl pyrophosphate (IPP) and GPX4, after treatment with ART. Conclusion: In conclusion, our study demonstrated that the antimalarial drug ART can inhibit nuclear localization of SREBP2, downregulate IPP and GPX4, and eventually trigger ferroptosis in myeloma cells. Through this study, we hope to establish a correlation between nuclear localization pathways and mediation of ferroptosis in myeloma cells and provide an innovative direction for exploration-related therapy.

The effect of artesunate to reverse CLP-induced sepsis immunosuppression mice with secondary infection is tightly related to reducing the apoptosis of T cells via decreasing the inhibiting receptors and activating MAPK/ERK pathway.

T cells play an important role in regulating immune system balance. Sepsis-associated immunosuppression causes apoptosis of T cells and a decrease in their number. Previously, artesunate was found to have an immunomodulatory effect on immunosuppression in model mice with cecal ligation and puncture (CLP)-induced sepsis. In the present study, mouse sepsis models of CLP and CLP with secondary infection were established and treated with artesunate in order to examine the effect of artesunate on adaptive immune response in sepsis-related immunosuppression. The results showed that artesunate treatment could increase the survival rate of CLP mice with secondary Pseudomonas aeruginosa infection, increase the bacterial clearance rate, and also increase the level of the pro-inflammatory cytokine TNF-α. In addition, artesunate resulted in an increase in the number of T cells, CD4+ T cells and CD8+ T cells, and inhibited CD4+ and CD8+ T-cell apoptosis. Artesunate was also found to inhibit the expression of the inhibitory receptors of PD-1, CTLA-4, and BTLA, but it did not affect the expression of Tim-3. Additionally, artesunate significantly increased the phosphorylated ERK level of CD4+ T cells and CD8+ T cells and inhibited mitochondrial pathway-mediated apoptosis in CLP mice with Pseudomonas aeruginosa infection. These findings reveal that artesunate has an immunomodulatory effect on the adaptive immune response in sepsis. These effects include an increase in the numbers of T cells, CD4+ T cells, and CD8+ T cells through inhibition of the expression of inhibitory receptors and promotion of the MAPK/ERK pathway.

Antimalarial Agents Targeting Plasmodium falciparum Carbonic Anhydrase: Towards Artesunate Hybrid Compounds with Dual Mechanism of Action.

Malaria continues to be a major public health challenge worldwide and, as part of the global effort toward malaria eradication, plasmodium carbonic anhydrases (CAs) have recently been proposed as potential targets for malaria treatment. In this study, a series of eight hybrid compounds combining the Artesunate core with a sulfonamide moiety were synthesized and evaluated for their inhibition potency against the widely expressed human (h) CAs I, II and the isoform from P. falciparum (PfCA). All derivatives demonstrated high inhibition potency against PfCA, achieving a KI value in the sub-nanomolar range (0.35 nM). Two Compounds showed a selectivity index of 4.1 and 3.1, respectively, against this protozoan isoform compared to hCA II. Three Derivatives showed no cytotoxic effects on human gingival fibroblasts at 50 µM with a high killing rate against both P. falciparum and P. knowlesi strains with IC50 in the sub-nanomolar range, providing a wide therapeutic window. Our findings suggest that these compounds may serve as promising leads for developing new antimalarial drugs and warrant further investigation, including activity against antimalarial-resistant strains, mode of action studies, and in vivo efficacy assessment in preclinical mouse models of malaria.