Artemisinin attenuates doxorubicin induced cardiotoxicity and hepatotoxicity in rats

Plant-Derived Terpenoids: A Plethora of Bioactive Compounds with Several Health Functions and Industrial Applications-A Comprehensive Overview

Terpenoids are a large class of natural secondary plant metabolites which are highly diverse in structure, formed from isoprene units (C-5), associated with a wide range of biological properties, including antioxidant, antimicrobial, anti-inflammatory, antiallergic, anticancer, antimetastatic, antiangiogenesis, and apoptosis induction, and are considered for potential application in the food, cosmetics, pharmaceutical, and medical industries. In plants, terpenoids exert a variety of basic functions in growth and development. This review gives an overview, highlighting the current knowledge of terpenoids and recent advances in our understanding of the organization, regulation, and diversification of core and specialized terpenoid metabolic pathways and addressing the most important functions of volatile and non-volatile specialized terpenoid metabolites in plants. A comprehensive description of different aspects of plant-derived terpenoids as a sustainable source of bioactive compounds, their biosynthetic pathway, the several biological properties attributed to these secondary metabolites associated with health-promoting effects, and their potential industrial applications in several fields will be provided, and emerging and green extraction methods will also be discussed. In addition, future research perspectives within this framework will be highlighted. Literature selection was carried out using the National Library of Medicine, PubMed, and international reference data for the period from 2010 to 2024 using the keyword "terpenoids". A total of 177,633 published papers were found, of which 196 original and review papers were included in this review according to the criteria of their scientific reliability, their completeness, and their relevance to the theme considered.

Cytoprotective effect of garlic alone versus co-administration of garlic and resveratrol in adriamycin-induced lung toxicity in albino rat: light microscopic, ultrastructural and immunohistochemical study

Adriamycin is a cytotoxic anthracycline antibiotic used to treat a wide variety of cancers. This study was made to detect the possible prophylactic effects of combining garlic and resveratrol in preventing adriamycin-induced pulmonary cytotoxicity. This study was conducted on a total number of 60 adult male albino rats. The rats were divided in an equally random manner into 6 groups: group I rats received nothing, group II received a dose of 50 mg/kg garlic extract orally for 3 weeks, group III received resveratrol in a dose of 20 mg/kg/day orally for 3 weeks, group IV rats were injected with 20 mg/kg adriamycin as a single dose via intraperitoneal route, group V received garlic extract for 3 weeks, then were injected with adriamycin in the same stated doses, and Group VI received garlic extract and resveratrol in same stated dose for 3 weeks, then were injected with adriamycin in the same stated dose. Lung specimens were processed for light microscopic, ultrastructural, and immunohistochemical studies. Adriamycin treatment caused histological alterations, thicker interstitial septa, extensive cellular infiltration, hypertrophied arterial wall, marked inducible Nitric Oxide Synthase immunoreaction, type I pneumocytes with destructed organelles as well as type II pneumocytes having large vacuoles. The combined garlic and resveratrol group demonstrated a considerable improvement in the changes to the histology and ultrastructure of adriamycin-induced lung injury. Combining garlic and resveratrol can prevent adriamycin-induced lung cytotoxicity in albino rats.

Betaine alleviates doxorubicin-induced nephrotoxicity by preventing oxidative insults, inflammation, and fibrosis through the modulation of Nrf2/HO-1/NLRP3 and TGF-β expression

Doxorubicin (Dox) is an anthracycline antibiotic used to treat various cancers and shows severe toxicity in multiple organ systems, including kidneys. Evidence shows that betaine's antioxidant and anti-inflammatory properties could prevent the onset of several disorders. Hence, the present study aims to investigate the therapeutic potential of betaine on Dox-induced nephrotoxicity (DIN). Nephrotoxicity was induced in male Sprague Dawley rats using Dox at a dose of 4 mg/kg (cumulative dose: 20 mg/kg) by the intraperitoneal route and cotreated with betaine through oral gavage (200 and 400 mg/kg) for 28 days. At the end of the experiment, biochemical, oxidative stress parameters, histopathology, and qRT-PCR were performed. DIN was indicated by elevated serum creatinine, urea, and decreased albumin levels representing kidney damage; the histopathological lesions (increased capsular space, renal tubule damage, and fibrosis) in renal tissues supported these biochemical findings. Interestingly, betaine treatment improves these alterations in Dox-treated rats. Further, betaine treatment decreases the lipid peroxidation and nitrite concentration and increases the superoxide dismutases and catalase enzyme concentration in Dox-treated rats. Fascinatingly, at the molecular level, DIN in rats shows upregulation of the Nrf2/HO-1 gene, while betaine treatment attenuated its expression along with the downregulation of inflammatory genes (NLRP3, TLR-4, TNF-α, and IL-6) and fibrosis-related genes (TGF-β and Acta2) expression in Dox-treated rats. These results showed that betaine has reno-protective properties by reducing inflammatory and fibrotic mediators and enhancing antioxidant capacity in the renal tissue of rats treated with Dox. We believe betaine can be exploited as a dietary supplement to attenuate DIN.

Mechanism of Artemisia annua L. in the treatment of acute myocardial infarction: network pharmacology, molecular docking and in vivo validation

This study was to evaluate the potential mechanism of action of Artemisia annua L. (A. annua) in the treatment of acute myocardial infarction (AMI) using network pharmacology, molecular docking and in vivo experiments. 22 active chemical compounds and 193 drug targets of A. annua were screened using the Traditional Chinese Medicine System Pharmacological (TCMSP) database. 3876 disease targets were also collected. Then 158 intersection targets between AMI and A. annua were obtained using R 4.2.0 software. String database was used to construct the protein-protein interaction (PPI) network and 6 core targets (MAPK1, TP53, HSP90AA1, RELA, AKT1, and MYC) were screened. Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed using the R package. GO enrichment results were mainly related to cell responses to chemical stress and cell membrane microregions. KEGG pathways were mainly involved in lipids, atherosclerosis and fluid shear stress. In addition, molecular docking between A. annua active compounds and core targets showed high binding activity. As for in vivo validation, A. annua extract showed significant effects on improving post-infarction ventricular function, delaying ventricular remodeling, and reducing myocardial fibrosis and apoptosis. This study has revealed the potential components and molecular mechanisms of A. annua in the treatment of AMI. Our work also showed that A. annua has great effect on reducing myocardial fibrosis and scar area after infarction.

Artemisia annua Extract Attenuate Doxorubicin-Induced Hepatic Injury via PI-3K/Akt/Nrf-2-Mediated Signaling Pathway in Rats

Doxorubicin (DOX), which is used to treat cancer, has harmful effects that limit its therapeutic application. Finding preventative agents to thwart DOX-caused injuries is thus imperative. Artemisia annua has numerous biomedical uses. This study aims to investigate the attenuative effect of Artemisia annua leaf extract (AALE) treatment on DOX-induced hepatic toxicity in male rats. A phytochemical screening of AALE was evaluated. Forty male rats were used; G1 was a negative control group, G2 was injected with AALE (150 mg/kg) intraperitoneally (i.p) daily for a month, 4 mg/kg of DOX was given i.p to G3 once a week for a month, and G4 was injected with DOX as G3 and with AALE as G2. Body weight changes and biochemical, molecular, and histopathological investigations were assessed. The results showed that AALE contains promising phytochemical constituents that contribute to several potential biomedical applications. AALE mitigated the hepatotoxicity induced by DOX in rats as evidenced by restoring the alterations in the biochemical parameters, antioxidant gene expression, and hepatic histopathological alterations in rats. Importantly, the impact of AALE against the hepatic deterioration resulting from DOX treatment is through activation of the PI-3K/Akt/Nrf-2 signaling, which in turn induces the antioxidant agents.

An Overview of the Enhanced Effects of Curcumin and Chemotherapeutic Agents in Combined Cancer Treatments

Due to the progressive ageing of the human population, the number of cancer cases is increasing. For this reason, there is an urgent need for new treatments that can prolong the lives of cancer patients or ensure them a good quality of life. Although significant progress has been made in the treatment of cancer in recent years and the survival rate of patients is increasing, limitations in the use of conventional therapies include the frequent occurrence of side effects and the development of resistance to chemotherapeutic agents. These limitations are prompting researchers to investigate whether combining natural agents with conventional drugs could have a positive therapeutic effect in cancer treatment. Several natural bioactive compounds, especially polyphenols, have been shown to be effective against cancer progression and do not exert toxic effects on healthy tissues. Many studies have investigated the possibility of combining polyphenols with conventional drugs as a novel anticancer strategy. Indeed, this combination often has synergistic benefits that increase drug efficacy and reduce adverse side effects. In this review, we provide an overview of the studies describing the synergistic effects of curcumin, a polyphenol that has been shown to have extensive cytotoxic functions against cancer cells, including combined treatment. In particular, we have described the results of recent preclinical and clinical studies exploring the pleiotropic effects of curcumin in combination with standard drugs and the potential to consider it as a promising new tool for cancer therapy.

Preventive and therapeutic use of herbal compounds against doxorubicin induced hepatotoxicity: a comprehensive review

Doxorubicin (DOX) is associated with numerous acute and chronic dose-related toxicities including hepatotoxicity. This adverse reaction may limit the use of other chemotherapeutic agents with hepatic excretion, and so, its prevention is an important issue. The aim of this study was to conduct a comprehensive review of in vitro, in vivo and human studies regarding the protective effects of synthetic and naturally-occurring compounds against DOX-induced liver injury. The search was conducted in Embase, PubMed, and Scopus databases using the following keywords: "doxorubicin," "Adriamycin," "hepatotoxicity," "liver injury," "liver damage," and "hepatoprotective," and all articles published in English were included without time restriction. Forty eligible studies to the end of May 2022 finally were reviewed. Our results demonstrated that all of these drugs, except acetylsalicylic acid, had considerable hepatoprotective effects against DOX. In addition, none of the studied compounds attenuated the antitumor efficacy of DOX treatment. Silymairn was the only compound which is assessed in human studies and showed promising preventive and therapeutic effects. Altogether, our results demonstrated that most of compounds with antioxidant, anti-apoptosis, and anti-inflammatory properties are efficacious against DOX-induced hepatotoxicity and may be considered as a potential adjuvant agent for prevention of hepatotoxicity in cancer patients, after fully been assessed in well-designed large clinical trials.

Codelivery of Phytochemicals with Conventional Anticancer Drugs in Form of Nanocarriers

Anticancer drugs in monotherapy are ineffective to treat various kinds of cancer due to the heterogeneous nature of cancer. Moreover, available anticancer drugs possessed various hurdles, such as drug resistance, insensitivity of cancer cells to drugs, adverse effects and patient inconveniences. Hence, plant-based phytochemicals could be a better substitute for conventional chemotherapy for treatment of cancer due to various properties: lesser adverse effects, action via multiple pathways, economical, etc. Various preclinical studies have demonstrated that a combination of phytochemicals with conventional anticancer drugs is more efficacious than phytochemicals individually to treat cancer because plant-derived compounds have lower anticancer efficacy than conventional anticancer drugs. Moreover, phytochemicals suffer from poor aqueous solubility and reduced bioavailability, which must be resolved for efficacious treatment of cancer. Therefore, nanotechnology-based novel carriers are employed for codelivery of phytochemicals and conventional anticancer drugs for better treatment of cancer. These novel carriers include nanoemulsion, nanosuspension, nanostructured lipid carriers, solid lipid nanoparticles, polymeric nanoparticles, polymeric micelles, dendrimers, metallic nanoparticles, carbon nanotubes that provide various benefits of improved solubility, reduced adverse effects, higher efficacy, reduced dose, improved dosing frequency, reduced drug resistance, improved bioavailability and higher patient compliance. This review summarizes various phytochemicals employed in treatment of cancer, combination therapy of phytochemicals with anticancer drugs and various nanotechnology-based carriers to deliver the combination therapy in treatment of cancer.

Natural bioactive compounds-doxorubicin combinations targeting topoisomerase II-alpha: Anticancer efficacy and safety

Cancer is one of the leading causes of death worldwide, so pursuing effective and safe therapeutics for cancer is a key research objective nowadays. Doxorubicin (DOX) is one of the commonly prescribed chemotherapeutic agents that has been used to treat cancer with its antimitotic properties via inhibition of topoisomerase II (TOP2) activity. However, many problems hinder the broad use of DOX in clinical practice, including cardiotoxicity and drug resistance. Research in drug discovery has confirmed that natural bioactive compounds (NBACs) display a wide range of biological activities correlating to anticancer outcomes. The combination of NBACs has been seen to be an ideal candidate that might increase the effectiveness of DOX therapy and decreases its unfavorable adverse consequences. The current review discusses the chemo-modulatory mechanism and the protective effects of combined DOX with NBACs with a binding affinity (pKi) toward TOP2A more than pKi of DOX. This review will also discuss and emphasize the molecular mechanisms to provide a pathway for further studies to reveal other signaling pathways. Taken together, understanding the fundamental mechanisms and implications of combined therapy may provide a practical approach to battling cancer diseases.

Ameliorative effects of Liv-52 on doxorubicin-induced oxidative damage in rat liver

Hepatotoxicity is a common side effect of doxorubicin (Dox) treatment of cancer. Liv-52 is an ayurvedic medicine that is reported to ameliorate liver injury due to oxidative stress. We investigated the effects of Liv-52 on Dox induced oxidative damage to liver tissues of rats using biochemical and histopathological techniques. Thirty male rats were assigned randomly into three equal groups: control (CG), Dox group (DG) Liv-52 + Dox group (LD). Rats in the LD group received 50 mg/kg Liv-52 in distilled water via gastric gavage. Distilled water was given via the same route to the rats in the DG and CG groups. Rats in the LD and DG groups were injected intraperitoneally with 5 mg/kg Dox 1 h after administration of Liv-52 or distilled water. The procedure was repeated daily for 7 days. On day 8, the animals were sacrificed, and serum and tissue biochemical and histopathological assays were performed. The malondialdehyde level was increased significantly in the DG group, while glutathione and superoxide dismutase levels were significantly lower in the DG group compared to the LD and CG groups. The highest levels of alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase were found in the DG group, while the lowest levels were found in the CG group, which exhibited levels similar to those of the LD group. Treatment with Liv-52 prior to Dox treatment reduced the histopathologic changes in the Dox group. Therefore, pre-treatment with Liv-52 protected against Dox induced oxidative stress and hepatotoxicity.

Through network pharmacology and molecular docking to explore the underlying mechanism of Artemisia annua L. treating in abdominal aortic aneurysm

Background: Abdominal aortic aneurysm (AAA) is a degenerative disease that causes health problems in humans. However, there are no effective drugs for the treatment of AAA. Artemisia annua L. (A. annua) is a traditional herbal that has been widely used in cardiovascular disease. Based on network pharmacology and molecular docking technology, this study predicted the practical components and potential mechanisms of A. annua inhibiting the occurrence and development of AAA.

Methods: The main active ingredients and targets of A. annua were screened through the TCMSP database; the GeneCards, OMIM, PharmGkb, and TTD databases were used to search for the targeted genes of AAA and map them to the targets of the active ingredients to obtain the active ingredient therapy of A. annua. The targets of AAA were to construct a protein interaction network through the STRING platform. R software was used to carry out the enrichment analysis of GO and KEGG for relevant targets, and Cytoscape was used to construct the active ingredient-target network prediction model of A. annua. Finally, AutoDock Vina was used to verify the results of the active ingredients and critical targets.

Results: The main active ingredients obtained from A. annua for the treatment of AAA include quercetin, luteolin, kaempferol, isorhamnetin, and artemetin, as well as 117 effective targets, including RELA, MAPK14, CCND1, MAPK1, AKT1, MYC, MAPK8, TP53, ESR1, FOS, and JUN. The 11 targeted genes might play a key role in disease treatment. Enriched in 2115 GO biological processes, 159 molecular functions, 56 cellular components, and 156 KEGG pathways, inferred that its mechanism of action might be related to PI3K-Akt signaling pathway, fluid shear stress, atherosclerosis, and AGE-RAGE signaling pathway. Molecular docking results showed that the top five active components of A. annua had a good affinity for core disease targets and played a central role in treating AAA. The low binding energy molecular docking results provided valuable information for the development of drugs to treat AAA.

Conclusion: Therefore, A. annua may have multiple components, multiple targets, and multiple signaling pathways to play a role in treating AAA. A. annua may have the potential to treat AAA.

Curcumin Ameliorates Doxorubicin-Induced Cardiotoxicity and Hepatotoxicity Via Suppressing Oxidative Stress and Modulating iNOS, NF-κB, and TNF-α in Rats

Doxorubicin (DOX) is one of the widely used anti-tumor drugs. However, DOX-induced cardiotoxicity (DIC) and hepatotoxicity (DIH) are among the side effects that limited its therapeutic efficiency and clinical applicability. This study aimed to investigate the cardioprotective and hepatoprotective potentials of curcumin (CMN)-a bioactive polyphenolic compound-in alleviating DOX-induced cardiotoxicity (DIC) and hepatotoxicity (DIH) in male rats. A single intraperitoneal (i.p.) dose of DOX (20 mg/kg) was used to induce DIC and DIH. DOX-intoxicated rats were co-treated with CMN (100 mg/kg, oral) for 10 days before and 5 days after a single dose of DOX. We studied the anti-inflammatory and anti-oxidative activities of CMN on biochemical and immunohistochemical aspects. DOX disrupted cardiac and hepatic functions and stimulated oxidative stress and inflammation in both tissues that was confirmed biochemically and immunohistochemically. DOX enhanced inflammatory interferon-gamma (IFN-γ) and upregulated immunoexpression of nuclear factor-κB (NF-κB), inducible nitric oxide synthase (iNOS), and tumor necrosis factor-alpha (TNF-α). DOX induced structural alterations in both cardiac and hepatic tissues. CMN demonstrated cardioprotective potential through reducing cardiac troponin I (cTn1) and aspartate amino transaminase (AST). In addition, CMN significantly ameliorated liver function through decreasing alanine amino transaminase (ALT) and, gamma-glutamyl transferase (GGT), total cholesterol (TC), and triglycerides (TG). CMN demonstrated anti-inflammatory potential through decreasing IFN-γ levels and immunoexpression of iNOS, NF-κB, and TNF-α. Histopathologically, CMN restored DOX-associated cardiac and liver structural alterations. CMN showed anti-oxidative and anti-inflammatory potentials in both the cardiac and hepatic tissues. In addition, cTn1, IFN-γ, and AST could be used as blood-based biomarkers.

Phenols and terpenoids: natural products as inhibitors of NLRP3 inflammasome in cardiovascular diseases

Inflammatory infiltration has been implicated in the pathogenesis of cardiovascular diseases (CVDs). The NLRP3 inflammasome is involved in the development of several types of CVDs, including myocardial infarction, myocardial ischemia-reperfusion damage, heart failure, atrial fibrillation, and hypertension. Inhibiting the activity of NLRP3 inflammasome can inhibit the progress of CVDs. However, there is no NLRP3 inflammasome inhibitor in clinic, and it is very important to find a safe and effective NLRP3 inhibitor. Phenols and terpenoids are naturally natural products that have many anti-inflammatory effects in CVDs by modulating the NLRP3 inflammatory pathway. Thus, 20 natural products from phenols and terpenoids for the treatment of cardiovascular disease based on the inhibition of NLRP3 inflammasome were summarized and screened. Docking results showed salvianolic acid B and ellagic acid in phenols, and oridonin and triptolide in terpenoids had a better binding activity with NLRP3, which can provide theoretical support for finding novel NLRP3 inflammasome inhibitors or lead compounds in the future.

Mokko Lactone Attenuates Doxorubicin-Induced Hepatotoxicity in Rats: Emphasis on Sirt-1/FOXO1/NF-κB Axis

Doxorubicin (DOX), a common chemotherapeutic agent, suffers serious adverse effects including hepatotoxicity. Mokko lactone (ML) is a guainolide sesquiterpene with promising biological activities. The study aimed to evaluate the protection offered by ML against hepatotoxicity induced by DOX in rats. Our data indicated ML exhibited protective effects as evidenced by ameliorating the rise in serum activities of alanine transaminase, aspartate transaminase and alkaline phosphatase. This was confirmed histologically as ML prevented DOX-induced pathological alteration in liver architecture. Further, ML administration significantly prevented malondialdehyde accumulation, glutathione depletion and superoxide dismutase and catalase exhaustion. Antioxidant action of ML was associated with enhanced expression of the nuclear translocation of NF-E2-related factor 2 (Nrf2) and a lower expression of forkhead box protein O1 (FOXO1). Also, ML showed potent anti-inflammatory activities highlighted by decreased expression of interleukin 6, tumor necrosis factor α and nuclear factor κB (NF-κB). The anti-apoptotic effects of ML were associated with decreased Bax and enhanced Bcl-2 mRNA expression in liver tissues. ML caused a significant up-regulation in the expression of silent information regulator 1 (Sirt-1). Therefore, it can be concluded that ML prevents liver injury caused by DOX. This could partially be due to the ML regulatory activities on Sirt-1/FOXO1/NF-κB axis.

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.

Artemether confers neuroprotection on cerebral ischemic injury through stimulation of the Erk1/2-P90rsk-CREB signaling pathway

Ischemic stroke is one of the leading causes of death and disability among adults. Despite the economic burden of the disease, available treatment options are still very limited. With the exception of anti-thrombolytics and hypothermia, current therapies fail to reduce neuronal injury, neurological deficits and mortality rates, suggesting that the development of novel and more effective therapies against ischemic stroke is urgent. In the present study, we found that artemether, which has been used in the clinic as an anti-malarial drug, was able to improve the neurological deficits, attenuate the infarction volume and the brain water content in a middle cerebral artery occlusion (MCAO) animal model. Furthermore, artemether treatment significantly suppressed cell apoptosis, stimulated cell proliferation and promoted the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), P90^rsk and cAMP responsive element-binding protein (CREB). Artemether protective effect was attenuated by PD98059, an ERK1/2 inhibitor, administration. Similarly, in oxygen-glucose deprivation/reperfusion (OGD/RP) cell models, artemether pre-treatment induced the suppression of the intracellular ROS, the down-regulation of LDH activity, the reduction of caspase 3 activity and of the apoptosis cell rate and reversed the decrease of mitochondrial membrane potential. As with MCAO animal model, artemether promoted the activation of Erk1/2-P90^rsk-CREB signaling pathway. This effect was blocked by the inhibition or knock-down of ERK1/2. The present study provides evidences of the neuroprotective effect of artemether unravelling its potential as a new therapeutic candidate for the prevention and treatment of stroke.

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Artemether conferred neuroprotection in a middle cerebral artery occlusion (MCAO) animal model.

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Artemether conferred neuroprotection on oxygen-glucose deprivation/reperfusion-induced cell injury model.

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Artemether promoted the activation of Erk1/2-P90^rsk-CREB signaling pathway in vitro and in vivo.

Evaluation of doxorubicin-induced early multi-organ toxicity in male CD1 mice by biodistribution of 18F-FDG and 67Ga-citrate. Pilot study

The search for methods that identify early toxicity, induced by chemotherapy, is urgent. Changes in the biodistribution of radiopharmaceuticals could give information on early toxicity. Ten-week-old CD1 male mice were divided into four groups. Two groups were administered a weekly dose of 5 mg/kg of doxorubicin hydrochloride (DOX) for 5 weeks and the control groups were administered saline solution. One week after the end of treatment, the biodistribution of ¹⁸F-FDG and ⁶⁷Ga-citrate were carried out, as was the quantification of plasma enzymes CK, CK-MB, LDH and AST. All enzymes were higher in the treated animals, but only significant (p < 0.05) in the case of CK-MB. ¹⁸F-FDG uptake increased in all organs of treated animals except retroperitoneal fat, being significant in spleen, brain, heart, liver, lung, kidney, and inguinal fat. ⁶⁷Ga-citrate had a more complex pattern. The uptake in the DOX group was higher in spleen, lung, kidney, testes, and gonadal fat, it did not change in brain, heart, and liver, and it was lower in the rest of the organs. It only showed significant differences in lung and pancreas. A thorough discussion of the possible causes that produced the change in biodistributions of both radiopharmaceuticals is included. The pilot study showed that both radiopharmaceuticals could identify early multi-organ toxicity induced by DOX. Although ¹⁸F-FDG seems to be better, ⁶⁷Ga-citrato should not be ruled out a priori. The detection of early toxicity would serve to adopt treatments that prevent its progression, thus improving patient's quality of life.

Nrf2 Signaling Pathway in Chemoprotection and Doxorubicin Resistance: Potential Application in Drug Discovery

Doxorubicin (DOX) is extensively applied in cancer therapy due to its efficacy in suppressing cancer progression and inducing apoptosis. After its discovery, this chemotherapeutic agent has been frequently used for cancer therapy, leading to chemoresistance. Due to dose-dependent toxicity, high concentrations of DOX cannot be administered to cancer patients. Therefore, experiments have been directed towards revealing underlying mechanisms responsible for DOX resistance and ameliorating its adverse effects. Nuclear factor erythroid 2-related factor 2 (Nrf2) signaling is activated to increase levels of reactive oxygen species (ROS) in cells to protect them against oxidative stress. It has been reported that Nrf2 activation is associated with drug resistance. In cells exposed to DOX, stimulation of Nrf2 signaling protects cells against cell death. Various upstream mediators regulate Nrf2 in DOX resistance. Strategies, both pharmacological and genetic interventions, have been applied for reversing DOX resistance. However, Nrf2 induction is of importance for alleviating side effects of DOX. Pharmacological agents with naturally occurring compounds as the most common have been used for inducing Nrf2 signaling in DOX amelioration. Furthermore, signaling networks in which Nrf2 is a key player for protection against DOX adverse effects have been revealed and are discussed in the current review.

Polychemotherapy with Curcumin and Doxorubicin via Biological Nanoplatforms: Enhancing Antitumor Activity

Doxorubicin (DOX) is a well-known chemotherapeutic agent extensively applied in the field of cancer therapy. However, similar to other chemotherapeutic agents such as cisplatin, paclitaxel, docetaxel, etoposide and oxaliplatin, cancer cells are able to obtain chemoresistance that limits DOX efficacy. In respect to dose-dependent side effect of DOX, enhancing its dosage is not recommended for effective cancer chemotherapy. Therefore, different strategies have been considered for reversing DOX resistance and diminishing its side effects. Phytochemical are potential candidates in this case due to their great pharmacological activities. Curcumin is a potential antitumor phytochemical isolated from Curcuma longa with capacity of suppressing cancer metastasis and proliferation and affecting molecular pathways. Experiments have demonstrated the potential of curcumin for inhibiting chemoresistance by downregulating oncogene pathways such as MMP-2, TGF-β, EMT, PI3K/Akt, NF-κB and AP-1. Furthermore, coadministration of curcumin and DOX potentiates apoptosis induction in cancer cells. In light of this, nanoplatforms have been employed for codelivery of curcumin and DOX. This results in promoting the bioavailability and internalization of the aforementioned active compounds in cancer cells and, consequently, enhancing their antitumor activity. Noteworthy, curcumin has been applied for reducing adverse effects of DOX on normal cells and tissues via reducing inflammation, oxidative stress and apoptosis. The current review highlights the anticancer mechanism, side effects and codelivery of curcumin and DOX via nanovehicles.