Responses of the antioxidant system in QGY-7701 cells to the cytotoxicity and apoptosis induced by 1-octyl-3-methylimidazolium chloride

Benchmark Dose Estimation from Transcriptomics Data for Methylimidazolium Ionic Liquid Hepatotoxicity: Implications for Health Risk Assessment of Green Solvents

Ionic liquids (ILs), traditionally considered environmentally benign solvents, have shown potential toxicity to organisms, raising concerns about their safety. Among them, 1-octyl-3-methylimidazolium (M8OI) has been detected at high concentrations in soils and exhibits hepatotoxic properties. To uncover the molecular mechanisms underlying this toxicity, whole-transcriptome sequencing was performed, coupled with benchmark dose (BMD) modeling, to derive transcriptomic points-of-departure (tPOD) through dose-response analysis. The transcriptomic analysis identified 425, 667, and 567 differentially expressed genes (DEGs) following low (10 μmol/L), medium (50 μmol/L), and high (200 μmol/L) doses of M8OI exposure, respectively. Enrichment analysis revealed significant perturbations in pathways related to cytokine-cytokine receptor interaction and IL-17 signaling. BMD modeling yielded tPOD values of 1.51 μmol/L (median of the 20 most sensitive genes, omicBMD20), 2.98 μmol/L (tenth percentile of all genes, omicBMD10th), 6.83 μmol/L (mode of the first peak of all gene BMDs, omicBMDmode), and 5.9 μmol/L for pathway-level analysis. These transcriptomics-derived tPODs were at least 105-fold lower than M8OI's hepatotoxic concentration, as indicated by its EC50 of 723.6 μmol/L in HepG2 cells. Functional analysis of the transcriptomic data identified legionellosis, rheumatoid arthritis, and transcriptional misregulation in cancer as the most sensitive pathways affected by M8OI. These findings highlight the molecular mechanisms driving M8OI-induced hepatotoxicity and underscore the utility of transcriptomics in deriving sensitive and quantitative toxicity thresholds. The results provide critical insights for guideline-driven toxicological evaluations and regulatory decision-making, supporting a more comprehensive assessment of IL safety.

Mechanisms of cytotoxicity in six classes of ionic liquids: Evaluating cell cycle impact and genotoxic and apoptotic effects

Ionic liquids (ILs), earlier praised for their eco-friendliness, have emerged as key chemicals in advancing green chemistry, catalysis, solvent development, and more. However, the discovery of their notable toxicity has led to a controversial reputation of ILs and has shifted the research landscape towards understanding their biological impacts. The present study examines the mechanism of cytotoxicity of 32 ILs across six classes, highlighting their effects on the cell cycle of the Jurkat cell line. Focusing on five ILs with pronounced cytotoxicity, we uncover their genotoxic effects and their role in inducing apoptosis. Our findings suggest intricate interplay between the extrinsic and intrinsic apoptotic pathways at different time points after exposure to ILs. Moreover, the ILs studied displayed marked genotoxicity, likely stemming from the accumulation of double-strand DNA breaks in the Jurkat cells. This investigation offers a comprehensive view on interactions of ILs with eukaryotic cells, thereby providing new guidelines for developing safer pharmaceutical and industrial applications of these chemicals. The results not only broaden and enhance the previous perceptions but also open new avenues in research, emphasizing the dual potential of ILs in innovation and safety, and marking a significant step towards integrating chemical innovations with biological safety.

Cytotoxicity and cell membrane interactions of choline-based ionic liquids: Comparing amino acids, acetate, and geranate anions

Ionic liquids (ILs) have found diverse applications in research and industry. Biocompatible ILs, a subset considered less toxic than traditional ILs, have expanded their applications into biomedical fields. However, there is limited understanding of the toxicity profiles, safe concentrations, and underlying factors driving their toxicity. In this study, we investigated the cytotoxicity of 13 choline-based ILs using four different cell lines: Human dermal fibroblasts (HDF), epidermoid carcinoma cells (A431), cervical cancer cells (HeLa), and gastric cancer cells (AGS). Additionally, we explored the haemolytic activity of these ILs. Our findings showed that the cytotoxic and haemolytic activities of ILs can be attributed to the hydrophobicity of the anions and the pH of the IL solutions. Furthermore, utilising quartz crystal microbalance with dissipation (QCM-D), we delved into the interaction of selected ILs, including choline acetate [Cho][Ac] and choline geranate [Cho][Ge], with model cell membranes composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC). The QCM-D data showed that ILs with higher toxicities exhibited more pronounced interactions with membranes. Increased variations in frequency and dissipation reflected substantial changes in membrane fluidity and mass following the addition of the more toxic ILs. Furthermore, total internal reflection fluorescence microscopy study revealed that [Cho][Ac] could cause lipid rearrangements and pore formation in the membrane, while [Cho][Ge] disrupted the bilayer packing. This study advances our understanding of the cellular toxicities associated with choline-based ILs and provides valuable insights into their mechanisms of action concerning IL-membrane interactions. These findings have significant implications for the safe and informed utilisation of biocompatible ILs in the realm of drug delivery and biotechnology.

Undifferentiated HepaRG cells show reduced sensitivity to the toxic effects of M8OI through a combination of CYP3A7-mediated oxidation and a reduced reliance on mitochondrial function

The methylimidazolium ionic liquid M8OI (1-octyl-3-methylimidazolium chloride, also known as [C8mim]Cl) has been detected in the environment and may represent a hazard trigger for the autoimmune liver disease primary biliary cholangitis, based in part on studies using a rat liver progenitor cell. The effect of M8OI on an equivalent human liver progenitor (undifferentiated HepaRG cells; u-HepaRG) was therefore examined. u-HepaRG cells were less sensitive (>20-fold) to the toxic effects of M8OI. The relative insensitivity of u-HepaRG cells to M8OI was in part, associated with a detoxification by monooxygenation via CYP3A7 followed by further oxidation to a carboxylic acid. Expression of CYP3A7 - in contrast to the related adult hepatic CYP3A4 and CYP3A5 forms - was confirmed in u-HepaRG cells. However, blocking M8OI metabolism with ketoconazole only partly sensitized u-HepaRG cells. Despite similar proliferation rates, u-HepaRG cells consumed around 75% less oxygen than B-13 cells, reflective of reduced dependence on mitochondrial activity (Crabtree effect). Replacing glucose with galactose, resulted in an increase in u-HepaRG cell sensitivity to M8OI, near similar to that seen in B-13 cells. u-HepaRG cells therefore show reduced sensitivity to the toxic effects of M8OI through a combination of metabolic detoxification and their reduced reliance on mitochondrial function.

Mechanisms of Biological Effects of Ionic Liquids: From Single Cells to Multicellular Organisms

The review presents a detailed discussion of the evolving field studying interactions between ionic liquids (ILs) and biological systems. Originating from molten salt electrolytes to present multiapplication substances, ILs have found usage across various fields due to their exceptional physicochemical properties, including excellent tunability. However, their interactions with biological systems and potential influence on living organisms remain largely unexplored. This review examines the cytotoxic effects of ILs on cell cultures, biomolecules, and vertebrate and invertebrate organisms. Our understanding of IL toxicity, while growing in recent years, is yet nascent. The established findings include correlations between harmful effects of ILs and their ability to disturb cellular membranes, their potential to trigger oxidative stress in cells, and their ability to cause cell death via apoptosis. Future research directions proposed in the review include studying the distribution of various ILs within cellular compartments and organelles, investigating metabolic transformations of ILs in cells and organisms, detailed analysis of IL effects on proteins involved in oxidative stress and apoptosis, correlation studies between IL doses, exposure times and resulting adverse effects, and examination of effects of subtoxic concentrations of ILs on various biological objects. This review aims to serve as a critical analysis of the current body of knowledge on IL-related toxicity mechanisms. Furthermore, it can guide researchers toward the design of less toxic ILs and the informed use of ILs in drug development and medicine.

Effects of ionic liquids on biomembranes: A review on recent biophysical studies

Ionic liquids (ILs) have been emerged as a versatile class of compounds that can be easily tuned to achieve desirable properties for various applications. The ability of ILs to interact with biomembranes has attracted significant interest, as they have been shown to modulate membrane properties in ways that may have implications for various biological processes. This review provides an overview of recent studies that have investigated the interaction between ILs and biomembranes. We discuss the effects of ILs on the physical and chemical properties of biomembranes, including changes in membrane fluidity, permeability, and stability. We also explore the mechanisms underlying the interaction of ILs with biomembranes, such as electrostatic interactions, hydrogen bonding, and van der Waals forces. Additionally, we discuss the future prospects of this field.

Potential for cardiac toxicity with methylimidazolium ionic liquids

Methylimidazolium ionic liquids (MILs) are solvent chemicals used in industry. Recent work suggests that MILs are beginning to contaminate the environment and lead to exposure in the general population. In this study, the potential for MILs to cause cardiac toxicity has been examined. The effects of 5 chloride MIL salts possessing increasing alkyl chain lengths (2 C, EMI; 4 C, BMI; 6 C; HMI, 8 C, M8OI; 10 C, DMI) on rat neonatal cardiomyocyte beat rate, beat amplitude and cell survival were initially examined. Increasing alkyl chain length resulted in increasing adverse effects, with effects seen at 10^-5 M at all endpoints with M8OI and DMI, the lowest concentration tested. A limited sub-acute toxicity study in rats identified potential cardiotoxic effects with longer chain MILs (HMI, M8OI and DMI) based on clinical chemistry. A 5 month oral/drinking water study with these MILs confirmed cardiotoxicity based on histopathology and clinical chemistry endpoints. Since previous studies in mice did not identify the heart as a target organ, the likely cause of the species difference was investigated. qRT-PCR and Western blotting identified a marked higher expression of p-glycoprotein-3 (also known as ABCB4 or MDR2) and the breast cancer related protein transporter BCRP (also known as ABCG2) in mouse, compared to rat heart. Addition of the BCRP inhibitor Ko143 - but not the p-glycoproteins inhibitor cyclosporin A - increased mouse cardiomyocyte HL-1 cell sensitivity to longer chain MILs to a limited extent. MILs therefore have a potential for cardiotoxicity in rats. Mice may be less sensitive to cardiotoxicity from MILs due in part, to increased excretion via higher levels of cardiac BCRP expression and/or function. MILs alone, therefore may represent a hazard in man in the future, particularly if use levels increase. The impact that MILs exposure has on sensitivity to cardiotoxic drugs, heart disease and other chronic diseases is unknown.

Allelopathic inhibitory effect on the growth of microcystis aeruginosa by improved ultrasonic-cellulase extract of Vallisneria

The unique and efficient characteristics of allelopathy in submerged plants make it an environmentally friendly method to control harmful algal blooms. Increased research focus has been placed on the improved allelochemical extraction methods of submerged plants because of their cost-utility relationships. In this study, the growth inhibition effect of Vallisneria extract on Microcystis aeruginosa (M. aeruginosa) cells through the combination of enzyme and ultrasonic-assisted extraction method was analyzed. By establishing a co-cultivation experiment, the growth indicators, photosynthetic system, and oxidative stress system of M. aeruginosa were determined. The reactive oxygen species (ROS) and superoxide dismutase (SOD) activity, as well as the catalase (CAT) and Malondialdehyde (MDA) levels of algal cells were found to have increased significantly after co-cultivation, which indicated that the Vallisneria ultrasonic-cellulase extract could induce oxidative stress in Microcystis aeruginosa cells. The Vallisneria extract could promote at low concentrations and inhibit at high concentrations on the growth of Microcystis aeruginosa. The effective suppression of growth of algae cells with the extract was observed at 5 g/L (fresh weight). The results showed that the Vallisneria ultrasonic-cellulase extract had a significant inhibitory effect on M. aeruginosa, making the effective ingredients a useful reference for algae inhibitors.

Anticancer potential and through study of the cytotoxicity mechanism of ionic liquids that are based on the trifluoromethanesulfonate and bis(trifluoromethylsulfonyl)imide anions

Ionic liquids (ILs) are known for their unique physicochemical properties. However, despite the great number of published papers, still little attention has been paid to their biological activity. Anticancer potential and the molecular mechanisms underlying the toxicity of these compounds are especially interesting and still unexplored. In the current work, a broad analysis of the cytotoxicity towards colon and breast cancers as well as glioblastoma of the ILs with pyridinium, piperidinium, pyrrolidinium, and imidazolium cations and trifluoromethanesulfonate or bis(trifluoromethylsulfonyl)imide anions indicated previously as the most toxic for normal human dermal fibroblasts were presented. In the case of MCF-7 cells, the activity of 1-decyl-3-methylimidazolium trifluoromethanesulfonate was more than twice as high as cisplatin. It was found that the inhibition of the cell cycle of colon cancer and glioblastoma cells occurs in different phases. More importantly, the different types of cell death were detected for both selected ILs, namely 1-hexyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide and 1-hexyl-3-methylimidazolium trifluoromethane-sulfonate, on colon cancer and glioblastoma, respectively, apoptosis and autophagy, confirmed at the gene and protein levels. Additionally, kinetic studies of the reactive oxygen species indicated that the tested ILs disturbed the cellular redox homeostasis.

Mechanisms of action of ionic liquids on living cells: the state of the art

Ionic liquids (ILs) are a relatively new class of organic electrolytes composed of an organic cation and either an organic or inorganic anion, whose melting temperature falls around room-temperature. In the last 20 years, the toxicity of ILs towards cells and micro-organisms has been heavily investigated with the main aim to assess the risks associated with their potential use in (industrial) applications, and to develop strategies to design greener ILs. Toxicity, however, is synonym with affinity, and this has stimulated, in turn, a series of biophysical and chemical-physical investigations as well as few biochemical studies focused on the mechanisms of action (MoAs) of ILs, key step in the development of applications in bio-nanomedicine and bio-nanotechnology. This review has the intent to present an overview of the state of the art of the MoAs of ILs, which have been the focus of a limited number of studies but still sufficient enough to provide a first glimpse on the subject. The overall picture that emerges is quite intriguing and shows that ILs interact with cells in a variety of different mechanisms, including alteration of lipid distribution and cell membrane viscoelasticity, disruption of cell and nuclear membranes, mitochondrial permeabilization and dysfunction, generation of reactive oxygen species, chloroplast damage (in plants), alteration of transmembrane and cytoplasmatic proteins/enzyme functions, alteration of signaling pathways, and DNA fragmentation. Together with our earlier review work on the biophysics and chemical-physics of IL-cell membrane interactions (Biophys. Rev. 9:309, 2017), we hope that the present review, focused instead on the biochemical aspects, will stimulate a series of new investigations and discoveries in the still new and interdisciplinary field of "ILs, biomolecules, and cells."

Emerging risk from "environmentally-friendly" solvents: Interaction of methylimidazolium ionic liquids with the mitochondrial electron transport chain is a key initiation event in their mammalian toxicity

Recent studies have identified the 8C alkyl chain methylimidazolium ionic liquid 1-octyl-3-methylimidazolium in the environment and its potential to trigger the auto-immune liver disease primary biliary cholangitis. The toxicity of a range of methylimidazolium ionic liquids were therefore examined. Oxygen consumption was rapidly inhibited, with potency increasing with alkyl chain length. This preceded caspase 3/7 induction and DNA fragmentation. Time- and dose-dependent loss of dye reduction capacities reflected these effects, with a >700 fold difference in potency between 2C and 10C alkyl chain liquids. None of the ionic liquids directly inhibited mitochondrial complexes I-IV or complex V (F₀F₁-ATPase). However, dithionite reduction and ESR spectroscopy studies indicate a one electron reduction of oxygen in the presence of a methylimidazolium ionic liquid, suggesting methylimidazolium ionic liquids function as mitochondrial electron acceptors. However, only longer chain ionic liquids form a non-aqueous phase or micelle under aqueous physiological conditions and lead to increases in reactive oxygen species in intact cells. These data therefore suggest that the longer chain methylimidazolium liquids are toxic in sensitive liver progenitor cells because they both readily integrate within the inner mitochondrial membrane and accept electrons from the electron chain, leading to oxidative stress.

Changes in the gut microbiota of mice orally exposed to methylimidazolium ionic liquids

Ionic liquids are salts used in a variety of industrial processes, and being relatively non-volatile, are proposed as environmentally-friendly replacements for existing volatile liquids. Methylimidazolium ionic liquids resist complete degradation in the environment, likely because the imidazolium moiety does not exist naturally in biological systems. However, there is limited data available regarding their mammalian effects in vivo. This study aimed to examine the effects of exposing mice separately to 2 different methylimidazolium ionic liquids (BMI and M8OI) through their addition to drinking water. Potential effects on key target organs-the liver and kidney-were examined, as well as the gut microbiome. Adult male mice were exposed to drinking water containing ionic liquids at a concentration of 440 mg/L for 18 weeks prior to examination of tissues, serum, urine and the gut microbiome. Histopathology was performed on tissues and clinical chemistry on serum for biomarkers of hepatic and renal injury. Bacterial DNA was isolated from the gut contents and subjected to targeted 16S rRNA sequencing. Mild hepatic and renal effects were limited to glycogen depletion and mild degenerative changes respectively. No hepatic or renal adverse effects were observed. In contrast, ionic liquid exposure altered gut microbial composition but not overall alpha diversity. Proportional abundance of Lachnospiraceae, Clostridia and Coriobacteriaceae spp. were significantly greater in ionic liquid-exposed mice, as were predicted KEGG functional pathways associated with xenobiotic and amino acid metabolism. Exposure to ionic liquids via drinking water therefore resulted in marked changes in the gut microbiome in mice prior to any overt pathological effects in target organs. Ionic liquids may be an emerging risk to health through their potential effects on the gut microbiome, which is implicated in the causes and/or severity of an array of chronic disease in humans.

The toxicity of the methylimidazolium ionic liquids, with a focus on M8OI and hepatic effects

Ionic liquids are a diverse range of charged chemicals with low volatility and often liquids at ambient temperatures. This characteristic has in part lead to them being considered environmentally-friendly replacements for existing volatile solvents. However, methylimidazolium ionic liquids are slow to break down in the environment and a recent study at Newcastle detected 1 octyl 3 methylimidazolium (M8OI) - an 8 carbon variant methylimidazolium ionic liquid - in soils in close proximity to a landfill site. The current M8OI toxicity database in cultured mammalian cells, in experimental animal studies and in model indicators of environmental impact are reviewed. Selected analytical data from the Newcastle study suggest the soils in close proximity to the landfill site, an urban soil lacking overt contamination, had variable levels of M8OI. The potential for M8OI - or a structurally related ionic liquid - to trigger primary biliary cholangitis (PBC), an autoimmune liver disease thought to be triggered by an unknown agent(s) in the environment, is reviewed.

Ionic Liquids for Topical Delivery in Cancer

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The unique properties of ionic liquids make them quite appealing for diverse applications, from “green” solvents (1st generation ionic liquids) to finely tuned materials (2nd generation ionic liquids). A decade ago, a 3rd generation of ionic liquids emerged which is focused on their prospective clinical applications, either as drugs per se or as adjuvants in drug formulations. In recent years, research focused on the use of ionic liquids for topical drug delivery has been increasing and holds great promise towards clinical application against skin cancers. This article highlights the growing relevance of ionic liquids in medicinal chemistry and pharmaceutical technology, which is opening new windows of opportunity.

Ionic Liquids for Therapeutic and Drug Delivery Applications

BACKGROUND

Ionic liquids (ILs) are ionic compounds with highly tunable and remarkable properties which make them an important candidate in multiple domains such as extraction, synthesis, analytics, catalysis, biotechnology, therapeutics as well as pharmaceutical sciences.

OBJECTIVE

This review systematically highlights the classification, properties and toxicity of ionic liquids. It focuses on exploring the biological activity of ionic liquids, which includes antimicrobial and anticancer property along with an emphasis on the concept of Active Pharmaceutical Ingredient- Ionic Liquids (API-ILs) for explaining the emulsifier and solubility enhancement property of ILs. An elaborative discussion on the application of ILs for the development of oral, transdermal and topical drug delivery systems has also been presented with suitable literature support.

CONCLUSION

Ionic liquids possess exceptional potential in the field of medicine, biology and chemistry.

CYP3A4 and microRNA-122 are involved in the apoptosis of HepG2 cells induced by ILs 1-decyl-3-methylimidazolium bromide

Ionic liquids (ILs) as green alternatives for volatile organic solvents are increasingly used in commercial applications. It is necessary to explore the cytotoxic mechanism of ILs to reduce the risk to human health. For this purpose, cell viability, apoptosis, cytochrome P450 3A4 (CYP3A4), glucose transporter type 2 (GLUT2), and microRNA-122 (miR-122) gene expression in HepG2 cells was evaluated after IL exposure. The results showed that ILs reduced the viability of HepG2 cells through apoptotic cell death. Moreover, ILs markedly upregulated the transcription and protein levels of CYP3A4, but did not affect the expression of GLUT2 in either messenger RNA level or protein level. Finally, ILs increased the expression of miR-122 and inhibition of miR-122 with miR-122 inhibitor blocked ILs-induced apoptosis in HepG2 cells. This finding may contribute to an increased understanding of the in vitro molecular toxicity mechanism of ILs to further understand IL-related human health risks.

A Profile of the In Vitro Anti-Tumor Activity and In Silico ADME Predictions of Novel Benzothiazole Amide-Functionalized Imidazolium Ionic Liquids

A focused array of green imidazolium ionic liquids (ILs) encompassing benzothiazole ring and amide linkage were designed and synthesized using quaternization and metathesis protocols. The synthesized ILs have been fully characterized by usual spectroscopic methods and screened for their anticancer activities against human cancer cell lines originating from breast and colon cancers. Collectively, our biological data demonstrate that the newly synthesized series has variable anticancer activities in the examined cancer types. The synthesized ILs 8, 10 and 21-29 comprising the methyl and methyl sulfonyl benzothiazole ring emerged as the most potent compounds with promising antiproliferative activities relative to their benzothiazole ring counterparts. Furthermore, the mechanism underlying the observed anticancer activity was investigated. The most active compound 22 appears to exert its anticancer effect through apoptosis dependent pathway in breast cancer cells. Interestingly, compound 22 has also shown good in silico absorption (81.75%) along with high gastro-intestinal absorption as per ADME predictions.

Scutellarin Exerts Hypoglycemic and Renal Protective Effects in db/db Mice via the Nrf2/HO-1 Signaling Pathway

This study investigated the hypoglycemic and renal protective effects of scutellarin (SCU) in db/db mice and elucidated the underlying mechanisms. The oral administration of metformin hydrochloride (Met) at 120 mg/kg and SCU at 25, 50, and 100 mg/kg over an eight-week period had hypoglycemic effects, demonstrated by decreases in body weight, blood glucose, food and water intake, and glycated hemoglobin activity and by augmented insulin levels and pyruvate kinase activity in the serum of db/db mice. SCU alleviated dyslipidemia by decreasing the levels of triglycerides and total cholesterol and enhancing the levels of high-density lipoprotein cholesterol in the serum of db/db mice. SCU reversed the overexpression of mRNA of renal damage markers (receptor for advanced glycation end products, neutrophil gelatinase-associated lipocalin, and kidney injury molecule 1), macrophage marker CD11b, and T cell marker CD3 in kidney of db/db mice. Pathological examination confirmed that SCU improved the organ structures of hyperglycemia-damaged livers, kidneys, and pancreas islets. Antibody array assay and enzyme-linked immunosorbent assay were combined to screen and analyze the regulatory effects of SCU on inflammatory factors and oxidative enzymes. SCU exerted anti-inflammatory effects by inhibiting the levels of proinflammatory cytokines (glycogen synthase kinase, intercellular adhesion molecule 2, and interleukin 1β and 2) and promoting anti-inflammatory cytokines (interleukin 4). SCU decreased the reactive oxygen species and malondialdehyde concentrations and increased the activity levels of antioxidative enzymes (superoxide dismutase, glutathione peroxidase, and catalase) in serum and kidneys. Furthermore, SCU upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), which in turn improved heme oxygenase 1 (HO-1), superoxide dismutase 1 and 2, and catalase expression levels in kidneys. The study showed that SCU has at least partial hypoglycemic and renal protective effects in db/db mice, and the mechanism is the modulation of the Nrf2/HO-1 signaling pathway.

Insight into the negative impact of ionic liquid: A cytotoxicity mechanism of 1-methyl-3-octylimidazolium bromide

Ionic liquids (ILs) as a green replacement for volatile organic solvents are increasingly used in large-scale commercial applications. A good understanding of the toxic mechanisms and environmental impact of ILs is neede to reduce the risk for human health and the environment. For this purpose, we aimed to evaluate the possible impacts of 1-methyl-3-octylimidazolium bromide ([C₈mim]Br) exposure on human hepatocellular carcinoma (HepG2) cells as to elucidate the cytotoxic mechanism of [C₈mim]Br. Biochemical assays revealed that [C₈mim]Br exposure altered the protein levels of heat shock protein 70 (HSP70) and HSP90, generally inhibiting total antioxidative capacity (T-AOC), depleting heme oxygenase-1 (HO-1) and increasing transcription and activity of inducible nitric oxide synthase (iNOS) in HepG2 cells. These results indicated that [C₈mim]Br may induce biochemical disturbances and cause oxidative stress in HepG2 cells. Moreover, increased phosphorylation of p53, mitochondrial membrane disruption, cyclooxygenase-2 activation, Bcl-2 family protein modulation, cytochrome c and Smac/DIABLO release, and inhibition of apoptosis inhibitory protein-2 (c-IAP2) and survivin were also observed in [C₈mim]Br-treated cells, suggesting that [C₈mim]Br-induced apoptosis might be mediated by the mitochondrial pathway. Further research showed that [C₈mim]Br exposure increased tumour necrosis factor α (TNF-α) transcription and content and promoted the expression of Fas and FasL, indicating that TNF-α and Fas/FasL are involved in the apoptosis induced by [C₈mim]Br. Additionally, [C₈mim]Br cytotoxicity was partly inhibited by N-acetyl-cysteine (NAC), and NAC reversed [C₈mim]Br-mediated mitochondrial dysfunction and blocked apoptotic events by inhibiting the generation of reactive oxygen species (ROS). This work first demonstrated that the ROS-mediated mitochondrial and death receptor-initiated apoptotic pathway is involved in [C₈mim]Br-induced HepG2 cell apoptosis.

Toxicity of imidazoles ionic liquid [C16mim]Cl to Hela cells

Our study aimed to evaluate the toxicity of 1-hexadecyl-3-methylimidazolium chloride ([C₁₆min]Cl) on the human cervical carcinoma (Hela) cells. We evaluated toxicity, cell viability, genotoxicity, oxidative stress, apoptosis, and apoptosis-related gene expression in Hela cells following exposure to [C₁₆min]Cl. The results indicated that [C₁₆min]Cl inhibited the growth of Hela cells, decreased cell viability, induced DNA damage and apoptosis, inhibited superoxide dismutase, decreased glutathione content, as well as increased the cellular malondialdehyde level of Hela cells. Moreover, [C₁₆min]Cl induced changes in the transcription of p53, Bax and Bcl-2, suggesting that the p53 and Bcl-2 family might have been involved in the cytotoxicity and apoptosis induced by [C₁₆min]Cl in Hela cells. Taken together, these results revealed that [C₁₆min]Cl imparts oxidative stress, genotoxicity, and induces apoptosis in Hela cells; hence, it is not a green solvent.

[omim][BF4]-mediated toxicity in mussel hemocytes includes its interaction with cellular membrane proteins

The current study is based on the increasing demand for the assessment of ionic liquid (IL)-mediated aquatic toxicity. Specifically, although a lot of studies have been performed so far, investigating IL-mediated adverse effects on numerous aquatic organisms, little is known about their mode of action. Given that the use of in vitro models is considered as a reliable tool for determining the mediated biological effects, the modulation of specific biochemical pathways and the onset of various forms of damage with great precision and reproducibility, mixed primary cultures of mussel Mytilus galloprovincialis hemocytes were used for investigating whether 1-octyl-3-methylimidazolium tetrafluoroborate ([omim][BF₄]) mediated toxicity is related to its interaction with cellular membrane proteins. Specifically, [omim][BF₄]-mediated cytotoxic, oxidative and genotoxic effects were investigated in mussel hemocytes before and after pre-treatment of cells with non-toxic concentration of guanidine hydrochloride (1 mM GndHCl). The results showed that [omim][BF₄] at concentrations ranging from 0.7 to 1.75 μM can induce cytotoxic (almost <50% reduction of cell viability), oxidative (increased levels of O₂^•- production and lipid peroxidation by-products) and genotoxic (increased levels of DNA damage) effects, while cells pre-treated with 1 mM GndHCl showed a significant attenuation of IL's toxic potency in all cases. According to the latter, the current study showed that [omim][BF₄]-mediated toxicity could be related not only to its well-known interaction with membrane lipid bilayers, but also to its interference with membrane proteins. Using GndHCl, a chaotropic agent that disrupts the hydrogen bonding network and the stability of membrane proteins via its interference with the intramolecular interactions mediated by non-covalent forces on cellular membranes, it was firstly shown that altering the membrane integrity as well as the native state of cellular membrane proteins, by weakening the hydrophobic effect, could attenuate the possible interaction of [omim][BF₄] with cellular membranes and the concomitant induction of protein-based intracellular processes, commonly linked with the induction of severe cellular damage.

Toxicity of imidazoles ionic liquid [C16mim]Cl to HepG2 cells

Ionic liquids have garnered increasing attention due to their capacity for low vapor pressure, lack of flammability, designability, good stability, and as a asubstitute for conventional organic solvents. However, their toxicity to various organisms has caused growing concern in recent years. Our study aims to evaluate the toxicity of 1-hexadecyl-3-methylimidazolium chloride ([C₁₆min]Cl) to human hepatocellular carcinoma (HepG2) cells, including cell viability, genotoxicity, oxidative stress, apoptosis, cell cycle, and apoptosis-related gene expression. Our results with HepG2 cells suggested that [C₁₆min]Cl inhibited cellular growth, decreased cell viability, induced DNA damage and apoptosis, inhibited superoxide dismutase, decreased glutathione content, increased cellular malondialdehyde levels as well as altering the cell cycle. Moreover, the induction of [C₁₆min]Cl altered the transcription of p53, Bax and Bcl-2, which are critical for controlling cell cycles progression and death, which suggests its involvement with cytotoxicity and apoptosis induced by [C₁₆min]Cl in HepG2 cells. Taken together, these results revealed that [C₁₆min]Cl exerted genotoxicity, oxidative stress and induced apoptosis in HepG2 cells; hence, it is not a healthy solvent.

The anti-fatigue activities of Tuber melanosporum in a mouse model

Tuber melanosporum (TM) is an edible fungus that exhibits antioxidant and anti-tumor activity via its unique bioactive metabolites. The present study analyzed the anti-fatigue effects of TM using a BALB/c mouse model. The anti-fatigue properties of TM were evaluated by assessing the endurance of mice by performing forced swimming, rotary rod and running tests. Following 2 weeks TM treatment, hepatic and muscular ATP, and glycogen levels were increased in mice subjected to 30 min swimming, compared with controls. Similarly, levels of serum lactic acid and lactic dehydrogenase were decreased in the same group, compared with the control. Additionally, TM treatment reduced reactive oxygen species and malondialdehyde levels, and increased superoxide dismutase and glutathione peroxidase levels in the muscle, liver and/or serum. The effect of TM on hormone levels was also investigated in the present study, as different efficacies of TM were observed in male and female mice. TM treatment increased serum levels of progesterone, estradiol and testosterone in female and male mice, whereas a decrease in serum luteinizing hormone levels was only observed in females. A decrease in serum follicle-stimulating hormone levels was identified in females, whereas an increase was observed in males. The current study demonstrated that the anti-fatigue effects of TM occur via the regulation of oxidative stress, energy metabolism and hormone levels.

Toxicity mechanisms of ionic liquids

Over the past three decades a growing awareness of environmental protection prompted the development of so-called green and sustainable technologies. Therefore, academic and wider community intensively explores new chemicals and safer, more energy efficient processes based on a rational compromise between economic, social, and environmental requirements. Due to low volatility and stability, ionic liquids emerged as a potential replacement for traditional volatile and harmful organic solvents. Various studies have been carried out to validate the green character of ionic liquids, whereby data published suggest that these compounds, due to their relatively high toxicity and poor biodegradability, could have an extremely negative impact on the environment. This paper presents the current knowledge on the toxicity of ionic liquids, with a special emphasis on the mechanisms by which this group of compounds causes changes in the morphology and physiology of organisms at different organisational levels of the ecosystem.

The role of phosphatidylinositol-3-OH-kinase (PI3-kinase) and respiratory burst enzymes in the [omim][BF4]-mediated toxic mode of action in mussel hemocytes

The present study investigates the role of phosphatidylinositol-3-OH-kinase (PI3-kinase) and respiratory burst enzymes, NADPH oxidase and NO synthase, in the 1-methyl-3-octylimidazolium tetrafluoroborate ([omim][BF₄])-mediated toxic mode of action in mussel hemocytes. Specifically, cell viability (using the neutral red uptake assay) was primarily tested in hemocytes treated with different concentrations of [omim][BF₄] (0.1-10 mg L^-1) and thereafter [omim][BF₄]-mediated oxidative (in terms of superoxide anions/O₂^- and nitric oxide/NO generation, as well as the enhancement of lipid peroxidation by-products, in terms of malondialdehyde/MDA) and genotoxic (in terms of DNA damage) effects were determined in hemocytes treated with 1 mg L^-1 [omim][BF₄]. Moreover, in order to investigate, even indirectly and non-entirely specific, the role of PI3-kinase, NADPH oxidase and NO synthase, the [omim][BF₄]-mediated effects were also investigated in hemocytes pre-incubated with wortmannin (50 nM), diphenyleneiodonium chloride (DPI 10 μM) and N^G-nitro-_l-arginine methyl ester (l-NAME 10 μM), respectively. The results showed that [omim][BF₄] ability to enhance O₂^-, NO, MDA and DNA damage, via its interaction with cellular membranes, was significantly attenuated in the presence of each inhibitor in almost all cases. The current findings revealed for the first time that certain signaling molecules, such as PI3-kinase, as well as respiratory burst enzymes activation, such as NADPH oxidase and NO synthase, could merely attribute to the [omim][BF₄]-mediated mode of action, thus enriching our knowledge for the molecular mechanisms of ILs toxicity.

The role of acetone in the [omim][BF4]-mediated adverse effects on tissues of mussels, human lymphocytes and the fruit fly Drosophila melanogaster

The present study investigated [omim][BF₄]-mediated adverse effects on biological models widely used in toxicological studies. Specifically, mussels of the genus Mytilus, human lymphocytes and fruit flies of the species Drosophila melanogaster, were exposed to [omim][BF₄] at concentrations ranging from micro- to milligrams per liter, with or without the presence of acetone as a carrier solvent and thereafter [omim][BF₄]-mediated adverse effects were analyzed appropriately (stress indices, such as lipid peroxidation byproducts, acetylcholinesterase/AChE activity and micronucleus/MN formation frequency, in mussel gills, Cytokinesis Block Micronucleus/CBMN assay and SMART test in human lymphocytes and fruit flies respectively). LC-MS-TOF analysis was also performed for elucidating [omim][BF₄] mode of action in the presence of the carrier solvent. The results showed the toxic potential of [omim][BF₄], as well as acetone's ability to attenuate [omim][BF₄]-mediated toxicity in almost all cases, probably due to the significant effect of acetone on the hydrophilic-lipophilic character and the viscosity of [omim][BF₄], as well as its interaction and permeability on the cell membranes. The slight involvement of acetone in the attenuation of [omim][BF₄]-mediated genotoxic effects on D. melanogaster could be due to species feeding experimental conditions, thus favoring the induction of antioxidant defense system against the [omim][BF₄]-mediated effects in all cases.

Environmental Impact of Ionic Liquids: Recent Advances in (Eco)toxicology and (Bio)degradability

This Review aims to integrate the most recent and pertinent data available on the (bio)degradability and toxicity of ionic liquids for global and critical analysis and on the conscious use of these compounds on a large scale thereafter. The integrated data will enable focus on the recognition of toxicophores and on the way the community has been dealing with them, with the aim to obtain greener and safer ionic liquids. Also, an update of the most recent biotic and abiotic methods developed to overcome some of these challenging issues will be presented. The review structure aims to present a potential sequence of events that can occur upon discharging ionic liquids into the environment and the potential long-term consequences.

Antifatigue Effects of Antrodia cinnamomea Cultured Mycelium via Modulation of Oxidative Stress Signaling in a Mouse Model

Antrodia cinnamomea, a folk medicinal mushroom, has numerous biological effects. In this study, we aim to assess whether the antifatigue effects of A. cinnamomea mycelia (AC) and its underlying mechanisms are related to oxidative stress signaling using behavioral mouse models and biochemical indices detection. Mice were orally treated with AC at doses of 0.1, 0.3, and 0.9 g/kg for three weeks. AC had no effect on the spontaneous activities of mice indicating its safety on central nervous system. Furthermore, results obtained from weight-loaded forced swimming test, rotary rod test, and exhausted running test confirmed that AC significantly enhanced exercise tolerance of mice. Biochemical indices levels showed that these effects were closely correlated with inhibiting the depletion of glycogen and adenosine triphosphate stores, regulating oxidative stress-related parameters (superoxide dismutase, glutathione peroxidase, reactive oxygen species, and malondialdehyde) in serum, skeletal muscle, and liver of mice. Moreover, the effects of AC may be related with its regulation on the activations of AMP-activated protein kinase, protein kinase B, and mammalian target of rapamycin in liver and skeletal muscle of mice. Altogether, our data suggest that the antifatigue properties of AC may be one such modulation mechanism via oxidative stress-related signaling in mice.

The Anticancer Potential of Ionic Liquids

Among the many challenges that the pharmaceutical industry currently faces is the need to develop innovative and effective therapies. The investigation of alternative and effective therapies against cancer is a current goal of the pharmaceutical industry. Ionic liquids (ILs) have emerged recently as a topic of study by researchers in the pharmaceutical industry in their search for new therapeutic agents. By definition, ILs are organic salts with melting points below 100 °C that are composed only by ions. Their main advantage lies in the numerous possible combinations of cations and anions, which allow adjustments in their physicochemical properties. The combination between ILs and active pharmaceutical ingredients (APIs) may improve the properties of APIs. In addition, the antitumor properties of these compounds have been described. Several studies have reported the use of ILs in biomedical applications as therapeutic agents, namely as antitumor agents. This review describes the recent proposed applications of ILs as antitumor agents.

Cytotoxicity, oxidative stress, and apoptosis in HepG2 cells induced by ionic liquid 1-methyl-3-octylimidazolium bromide

The present study aimed to determine the cytotoxicity of 1-methyl-3-octylimidazolium bromide ([C8mim]Br) on the human hepatocellular carcinoma (HepG2) cells in order to elucidate the biochemical and molecular mechanism of [C8mim]Br-cytotoxicity. For this purpose, cell viability, oxidative stress, apoptosis, caspase activity, and apoptosis-related gene expression in HepG2 cells following [C8mim]Br-exposure were evaluated. The results showed that viability of HepG2 cells was decreased by [C8mim]Br-exposure in a concentration-dependent pattern. Moreover, biochemical assays reveal that [C8mim]Br-exposure can induce apoptosis, cause overproduction of reactive oxygen species (ROS), inhibit superoxide dismutase and catalase, reduce glutathione content, and increase the cellular malondialdehyde level of HepG2 cells. The transcriptions of p53 and bax were markedly up-regulated while bcl-2 was significantly down-regulated in HepG2 cells after [C8mim]Br-exposure, suggesting that p53 and bcl-2 family may be involved in the cytotoxicity and apoptosis of HepG2 cells caused by [C8mim]Br. In addition, we also found that caspase-3, caspase-8, and caspase-9 were significantly activated in HepG2 cells following [C8mim]Br-exposure. Our results suggest that ROS may be a key early signal of [C8mim]Br-induced apoptosis and caspases play a key role in the initiation and execution of apoptosis of HepG2 cells.

Investigation of toxic effects of imidazolium ionic liquids, [bmim][BF4] and [omim][BF4], on marine mussel Mytilus galloprovincialis with or without the presence of conventional solvents, such as acetone

This study investigated the cytotoxic, oxidative and genotoxic effects of two commonly used imidazolium ionic liquids (ILs), [bmim][BF4] (1-butyl-3-methylimidazolium) and [omim][BF4] (1-methyl-3-octylimidazolium tetrafluoroborate), on the marine mussel Mytilus galloprovincialis, as well as whether acetone could mediate their toxic profile. In this context, mussels were firstly exposed to different concentrations of [bmim][BF4] or [omim][BF4], with or without the presence of acetone (at a final concentration of 0.06% v/v), for a period of 96h, in order to determine the concentration that causes 50% mussel mortality (LC50 values) in each case. Thereafter, mussels were exposed to sub- and non-lethal concentrations of ILs for investigating their ability to cause lysosomal membrane impairment (with the use of neutral red retention assay/NRRT), superoxide anion and lipid peroxidation byproduct (malondialdehyde/MDA) formation, as well as DNA damage and formation of nuclear abnormalities in hemocytes. The results showed that [omim][BF4] was more toxic than [bmim][BF4] in all cases, while the presence of acetone resulted in a slight attenuation of its toxicity. The different toxic behavior of ILs was further revealed by the significantly lower levels of NRRT values observed in [omim][BF4]-treated mussels, compared to those occurring in [bmim][BF4] in all cases. Similarly, [bmim][BF4]-mediated oxidative and genotoxic effects were observed only in the highest concentration tested (10mgL(-1)), while [omim][BF4]-mediated effects were enhanced at lower concentrations (0.01-0.05mgL(-1)). Overall, the present study showed that [bmim][BF4] and [omim][BF4] could induce not only lethal but also nonlethal effects on mussel M. galloprovincialis. The extent of [bmim][BF4] and/or [omim][BF4]-mediated effects could be ascribed to the length of each IL alkyl chain, as well as to their lipophilicity. Moreover, the role of acetone on the obtained toxic effects of the specific ILs was reported for the first time, giving evidence for its interaction with the ILs and the modulation of their toxicity.

Effect of 1-octyl-3-methylimidazolium chloride on cell replication and membrane permeability of Escherichia coli DH5α

Ionic liquids (ILs) have elicited attention due to their unique properties. ILs may pose environmental risks to aquatic ecosystems once released into water during generation and application. Therefore, the toxic and antimicrobial properties of ILs should be analysed. This study aims to evaluate the cytotoxicity of 1-octyl-3-methylimidazolium chloride ([C8mim] [Cl]) on Escherichia coli DH5α by MTT (3-[4,5-dimethylthiazol-2yl]-2,5 diphenyl tetrazolium bromide) assay, and to determine the effect of [C8mim] [Cl] on the replication and membrane permeability of E. coli DH5α. The results showed that [C8mim] [Cl] decreased cell viability and inhibited bacterial cell replication. [C8mim] [Cl] increased protein and nucleic acid contents in the extracellular fluid, damaged the cell membrane, and increased membrane permeability. The increase of cell membrane permeability induced by [C8mim] [Cl] could be the cause of decreased cell viability and replication.