Stimulation of pro-inflammatory responses by mebendazole in human monocytic THP-1 cells through an ERK signaling pathway

Decades Long Involvement of THP-1 Cells as a Model for Macrophage Research: A Comprehensive Review

Over the years, researchers have endeavored to identify dependable and reproducible in vitro models for examining macrophage behavior under controlled conditions. The THP-1 cell line has become a significant and widely employed tool in macrophage research within these models. Originating from the peripheral blood of individuals with acute monocytic leukemia, this human monocytic cell line can undergo transformation into macrophage-like cells, closely mirroring primary human macrophages when exposed to stimulants. Macrophages play a vital role in the innate immune system, actively regulating inflammation, responding to infections, and maintaining tissue homeostasis. A comprehensive understanding of macrophage biology and function is crucial for gaining insights into immunological responses, tissue healing, and the pathogenesis of diseases such as viral infections, autoimmune disorders, and neoplastic conditions. This review aims to thoroughly evaluate and emphasize the extensive history of THP-1 cells as a model for macrophage research. Additionally, it will delve into the significance of THP-1 cells in advancing our comprehension of macrophage biology and their invaluable contributions to diverse scientific domains.

Shear stress induces monocyte/macrophage-mediated inflammation by upregulating cell-surface expression of heat shock proteins

The loss of endothelial cells is associated with the accumulation of monocytes/macrophages underneath the surface of the arteries, where cells are prone to mechanical stimulation, such as shear stress. However, the impact of mechanical stimuli on monocytic cells remains unclear. To assess whether mechanical stress affects monocytic cell function, we examined the expression of inflammatory molecules and surface proteins, whose levels changed following shear stress in human THP-1 cells. Shear stress increased the inflammatory chemokine CCL2, which enhanced the migration of monocytic cells and tumor necrosis factor (TNF)-α and interleukin (IL)- 1β at transcriptional and protein levels. We identified that the surface levels of heat shock protein 70 (HSP70), HSP90, and HSP105 increased using mass spectrometry-based proteomics, which was confirmed by western blot analysis, flow cytometry, and immunofluorescence. Treatment with HSP70/HSP105 and HSP90 inhibitors suppressed the expression and secretion of CCL2 and monocytic cell migration, suggesting an association between HSPs and inflammatory responses. We also demonstrated the coexistence and colocalization of increased HSP90 immunoreactivity and CD68 positive cells in atherosclerotic plaques of ApoE deficient mice fed a high-fat diet and human femoral artery endarterectomy specimens. These results suggest that monocytes/macrophages affected by shear stress polarize to a pro-inflammatory phenotype and increase surface protein levels involved in inflammatory responses. The regulation of the abovementioned HSPs upregulated on the monocytes/macrophages surface may serve as a novel therapeutic target for inflammation due to shear stress.

Activation of Inflammation by MCF-7 Cells-Derived Small Extracellular Vesicles (sEV): Comparison of Three Different Isolation Methods of sEV

PURPOSE

Small extracellular vesicles (sEV) containing proteins and RNAs play important roles as intercellular signal mediators. A critical issue is that there are multiple methods to prepare sEV fractions. The purpose of this study was to examine whether cancer cell-derived sEV fractions prepared by different isolation methods show similar responses for the induction of inflammatory cytokines in macrophages.

METHODS

sEV fractions from the conditioned medium of MCF-7 cells were prepared by ultracentrifugation (UC), the MagCapture Exosome Isolation Kit PS (PS), or the ExoQuick-TC kit (EQ). The mRNA levels of inflammatory cytokines in differentiated THP-1 cells treated with the sEV fractions were evaluated.

RESULTS

The yields of sEV fractions obtained from 1 mL conditioned medium by UC, PS, or EQ were 3.2×10⁸ particles (0.27 μg protein), 12.8×10⁸ particles (0.87 μg protein) and 23.5 ×10⁸ particles (4.50 μg protein), respectively. The average particle sizes in the UC, PS, and EQ fractions were 184.8 ± 1.8 nm, 157.8 ± 1.3 nm and 165.8 ± 1.1 nm, respectively. CD9 and CD81, markers of sEV, were most highly detected in the PS fraction, followed by the EQ and UC fractions. These results suggest that PS gave sEV with relatively high purity, and many protein contaminants appear to be included in the EQ fraction. The mRNA levels of inflammatory cytokines in THP-1 macrophages were most prominently increased by treatment with the UC fraction, followed by the EQ and PS fractions, suggesting that contaminants rather than sEV may largely induce an inflammatory response.

CONCLUSION

The isolation method affects the evaluation of sEV function.

Mebendazole and temozolomide in patients with newly diagnosed high-grade gliomas: results of a phase 1 clinical trial

Background

Mebendazole is an anthelmintic drug introduced for human use in 1971 that extends survival in preclinical models of glioblastoma and other brain cancers.

Methods

A single-center dose-escalation and safety study of mebendazole in 24 patients with newly diagnosed high-grade gliomas in combination with temozolomide was conducted. Patients received mebendazole in combination with adjuvant temozolomide after completing concurrent radiation plus temozolomide. Dose-escalation levels were 25, 50, 100, and 200 mg/kg/day of oral mebendazole. A total of 15 patients were enrolled at the highest dose studied of 200 mg/kg/day. Trough plasma levels of mebendazole were measured at 4, 8, and 16 weeks.

Results

Twenty-four patients (18 glioblastoma and 6 anaplastic glioma) were enrolled with a median age of 49.8 years. Four patients (at 200 mg/kg) developed elevated grade 3 alanine aminotransferase (ALT) and/or aspartate transaminase (AST) after 1 month, which reversed with lower dosing or discontinuation. Plasma levels of mebendazole were variable but generally increased with dose. Kaplan–Meier analysis showed a 21-month median overall survival with 41.7% of patients alive at 2 years and 25% at 3 and 4 years. Median progression-free survival (PFS) from the date of diagnosis for 17 patients taking more than 1 month of mebendazole was 13.1 months (95% confidence interval [CI]: 8.8–14.6 months) but for 7 patients who received less than 1 month of mebendazole PFS was 9.2 months (95% CI: 5.8–13.0 months).

Conclusion

Mebendazole at doses up to 200 mg/kg demonstrated long-term safety and acceptable toxicity. Further studies are needed to determine mebendazole’s efficacy in patients with malignant glioma.

Differential Monocyte Actuation in a Three-Organ Functional Innate Immune System-on-a-Chip

A functional, human, multiorgan, pumpless, immune system-on-a-chip featuring recirculating THP-1 immune cells with cardiomyocytes, skeletal muscle, and liver in separate compartments in a serum-free medium is developed. This in vitro platform can emulate both a targeted immune response to tissue-specific damage, and holistic proinflammatory immune response to proinflammatory compound exposure. The targeted response features fluorescently labeled THP-1 monocytes selectively infiltrating into an amiodarone-damaged cardiac module and changes in contractile force measurements without immune-activated damage to the other organ modules. In contrast to the targeted immune response, general proinflammatory treatment of immune human-on-a-chip systems with lipopolysaccharide (LPS) and interferon-γ (IFN-γ) causes nonselective damage to cells in all three-organ compartments. Biomarker analysis indicates upregulation of the proinflammation cytokines TNF-α, IL-6, IL-10, MIP-1, MCP-1, and RANTES in response to LPS + IFN-γ treatment indicative of the M1 macrophage phenotype, whereas amiodarone treatment only leads to an increase in the restorative cytokine IL-6 which is a marker for the M2 phenotype. This system can be used as an alternative to humanized animal models to determine direct immunological effects of biological therapeutics including monoclonal antibodies, vaccines, and gene therapies, and the indirect effects caused by cytokine release from target tissues in response to a drug's pharmacokinetics (PK)/pharmacodynamics (PD) profile.

Layer-by-Layer Self-Assembly of Polyelectrolytes on Superparamagnetic Nanoparticle Surfaces

Designing and manufacturing multifunctional nanoparticles (NPs) are of considerable interest for both academic and industrial research. Among NPs used in this field, iron oxide NPs show low toxicity compared to metallic ones and are thus of high interest for biomedical applications. In this work, superparamagnetic Fe3-δO4-based core/shell NPs were successfully prepared and characterized by the combination of different techniques, and their physical properties were investigated. We demonstrate the efficiency of the layer-by-layer process to graft polyelectrolytes on the surface of iron oxide NPs. The influence of the polyelectrolyte chain configuration on the magnetic properties of the Fe3-δO4/polymer core/shell NPs was enlightened. The simple and fast process described in this work is efficient for the grafting of polyelectrolytes from surfaces, and thus, derived Fe3-δO4 NPs display both the physical properties of the core and of the macromolecular shell. Finally, the cytotoxicity toward the human THP-1 monocytic cell line of the core/shell NPs was assessed. The results showed that the polymer-capped Fe3-δO4 NPs exhibited almost no toxicity after 24 h of exposure at concentrations up to 25 μg mL-1. Our results show that these smart superparamagnetic nanocarriers with stealth properties are promising for applications in multimodal cancer therapy, including drug delivery.

Enterotoxigenic Escherichia coli Interferes FATP4-Dependent Long-Chain Fatty Acid Uptake of Intestinal Epithelial Enterocytes via Phosphorylation of ERK1/2-PPARγ Pathway

Sufficient fatty acid (FA) uptake from jejunal lumen is closely associated with pediatric growth. Enterotoxigenic Escherichia coli (ETEC), which poses a big threat to young mammals’ health, is also targeted on the jejunum, however, the effects on FA uptake is not understood yet. To explore the impacts of ETEC on the FA uptake ability of jejunum epithelial enterocytes during early life, we orally gavaged weaning piglets with ETEC K88 and found intestinal inflammation combined with compromised uptake of LCFA (C16:0, C18:0, C20:3, C20:4) except for C14:0 whose chain length is similar to medium chain fatty acid (MCFA). Furthermore, we observed reduced protein expression of TJs, fatty acid transport protein 4 (FATP4), peroxisome proliferator-activated receptor γ (PPARγ), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2), and upregulated expression of p-PPARγ. In the in vitro study, we challenged polarized porcine intestine jejunum cell line IPEC-J2 with ETEC K88 and discovered similar results on intestinal barrier and expression of associated genes combined with morphological changes. Based on the constructed cellular model, we then determined lower uptake of BODIPY-labeled C16:0 without any difference in the uptake of BODIPY-labeled C12:0. The content of intracellular triglyceride which was mainly synthesized by LCFA concomitantly lowered down. Using gene knock down and overexpression, FATP4 was confirmed to be responsible for LCFA uptake. Moreover, ERK1/2 inhibitor U0126 and PPARγ antagonist T0070907 revealed ETEC could initiate cascaded phosphorylation of ERK1/2 and PPARγ resulting in hindered expression of FATP4. These results indicate ETEC challenge will cause dysfunction in FATP4-dependent LCFA uptake by phosphorylation of ERK1/2 and PPARγ. Furthermore, intestinal uptake of MCFA is in a FATP4-independent manner which is not easily disturbed by ETEC.

Oxibendazole induces apoptotic cell death in proliferating porcine trophectoderm and uterine luminal epithelial cells via mitochondria-mediated calcium disruption and breakdown of mitochondrial membrane potential

The well-known and effective anthelmintic oxibendazole was recently shown to have a broad spectrum of biological abilities, such as anti-cancer and anti-inflammation activities. In contrast, the mechanism of oxibendazole's anti-proliferative effect via cell signaling pathways and its role in pre-implantation has not been studied. Therefore, in this study we demonstrated the effects of oxibendazole on the proliferation of porcine trophectoderm (pTr) cells and porcine luminal epithelial (pLE) cells, a well-known in vitro model system of the fetal-maternal interface. Cell proliferation decreased in both pTr and pLE cells in response to oxibendazole, and we determined that this was modulated through intracellular cell signal transduction. Phosphorylation of ERK1/2, P90RSK, and S6 were downregulated by exposure to a 200 nM dose of oxibendazole in both types of cells, while the expression of phosphorylated JNK, AKT, and P70S6K was upregulated. Pre-treatment with a PI3K/AKT inhibitor (Wortmannin), ERK1/2 inhibitor (U0126), and JNK inhibitor (SP600125) induced the signaling interactions of these molecules, and oxibendazole co-treatment with each inhibitor resulted in even greater decreases in cell proliferation. Furthermore, intracellular and mitochondrial calcium ion accumulation was observed, which would mean that calcium ion homeostasis was disrupted, causing damage to the mitochondrial membrane potential. These deteriorated conditions ultimately led to apoptotic cell death. Taken together, the results of the present study identified that the apoptotic effect of oxibendazole on pTr and pLE cells is regulated by cell signaling pathways, and thus oxibendazole could influence the connection between the conceptus and the maternal uterus.

Mebendazole stimulates CD14+ myeloid cells to enhance T-cell activation and tumour cell killing

Mebendazole (MBZ) was recently shown to induce a tumor suppressive M1 phenotype in THP-1 monocytes and macrophages. In the present study the immune effects of MBZ was further investigated using human peripheral blood mononuclear cells (PBMCs) co-cultured with tumour cells. The Biomap platform was used to screen for biomarkers induced from MBZ exposed co-cultures of T-cell receptor activated PBMCs, HT29 colon cancer cells and either human fibroblasts or human umbilical vein endothelial cells (HUVEC) cells. In these co-culture systems MBZ at 0.3-10 μM induced significant increases in TNFα and IFNγ indicating immune stimulation. PBMC cultures alone were subsequently tested for activation status and only in PBMCs activated by CD3/IL2 stimulation and MBZ, at a clinically achievable concentration, was able to increase PBMC clustering and release of pro-inflammatory IFNγ, TNFα, IL6 and IL1β cytokines. Moreover, when PBMC cultures were functionally tested for immune cell killing of lung cancer A549NucLightRed cells, MBZ significantly increased tumour cell apoptosis and reduced the number of surviving tumour cells. This effect was dependent on the presence of CD14 monocytes/macrophages in the co-culture. In summary, MBZ potentiated the immune stimulatory and anticancer effects of anti-CD3/IL2 activated PBMCs which could be relevant to explain the anticancer activity of MBZ observed in the clinic.

Benzimidazoles Promote Anti-TNF Mediated Induction of Regulatory Macrophages and Enhance Therapeutic Efficacy in a Murine Model

BACKGROUND AND AIMS

Regulatory macrophages play a critical role in tissue repair, and we have previously shown that anti-tumour necrosis factor [TNF] antibodies induce these macrophages in vitro and in vivo in IBD patients. The induction of regulatory macrophages can be potentiated using the combination of anti-TNF and thiopurines, consistent with the enhanced efficacy of this combination therapy described in clinical trials. As thiopurines are unfortunately associated with significant side effects, we here aimed to identify alternatives for combination therapy with anti-TNF, using the macrophage induction model as a screening tool.

METHODS

Mixed lymphocyte reactions were treated with anti-TNF and a library of 1600 drug compounds. Induction of CD14+CD206+ macrophages was analysed by flow cytometry. Positive hits were validated in vitro and in the T cell transfer model of colitis.

RESULTS

Among the 98 compounds potentiating the induction of regulatory macrophages by anti-TNF were six benzimidazoles, including albendazole. Albendazole treatment in the presence of anti-TNF resulted in alterations in the tubulin skeleton and signalling though AMPK, which was required for the enhanced induction. Combination therapy also increased expression levels of the immunoregulatory cytokine IL-10. In vivo, albendazole plus anti-TNF combination therapy was superior to monotherapy in a model of colitis, in terms of both induction of regulatory macrophages and improvement of clinical symptoms.

CONCLUSIONS

Albendazole enhances the induction of regulatory macrophages by anti-TNF and potentiates clinical efficacy in murine colitis. Given its favourable safety profile, these data indicate that the repurposing of albendazole may be a novel option for anti-TNF combination therapy in IBD.

The anticancer effect of mebendazole may be due to M1 monocyte/macrophage activation via ERK1/2 and TLR8-dependent inflammasome activation

Mebendazole (MBZ), a drug commonly used for helminitic infections, has recently gained substantial attention as a repositioning candidate for cancer treatment. However, the mechanism of action behind its anticancer activity remains unclear. To address this problem, we took advantage of the curated MBZ-induced gene expression signatures in the LINCS Connectivity Map (CMap) database. The analysis revealed strong negative correlation with MEK/ERK1/2 inhibitors. Moreover, several of the most upregulated genes in response to MBZ exposure were related to monocyte/macrophage activation. The MBZ-induced gene expression signature in the promyeloblastic HL-60 cell line was strongly enriched in genes involved in monocyte/macrophage pro-inflammatory (M1) activation. This was subsequently validated using MBZ-treated THP-1 monocytoid cells that demonstrated gene expression, surface markers and cytokine release characteristic of the M1 phenotype. At high concentrations MBZ substantially induced the release of IL-1β and this was further potentiated by lipopolysaccharide (LPS). At low MBZ concentrations, cotreatment with LPS was required for MBZ-stimulated IL-1β secretion to occur. Furthermore, we show that the activation of protein kinase C, ERK1/2 and NF-kappaB were required for MBZ-induced IL-1β release. MBZ-induced IL-1β release was found to be dependent on NLRP3 inflammasome activation and to involve TLR8 stimulation. Finally, MBZ induced tumor-suppressive effects in a coculture model with differentiated THP-1 macrophages and HT29 colon cancer cells. In summary, we report that MBZ induced a pro-inflammatory (M1) phenotype of monocytoid cells, which may, at least partly, explain MBZ's anticancer activity observed in animal tumor models and in the clinic.

Vildagliptin and its metabolite M20.7 induce the expression of S100A8 and S100A9 in human hepatoma HepG2 and leukemia HL-60 cells

Vildagliptin is a potent, orally active inhibitor of dipeptidyl peptidase-4 (DPP-4) for the treatment of type 2 diabetes mellitus. It has been reported that vildagliptin can cause hepatic dysfunction in patients. However, the molecular-mechanism of vildagliptin-induced liver dysfunction has not been elucidated. In this study, we employed an expression microarray to determine hepatic genes that were highly regulated by vildagliptin in mice. We found that pro-inflammatory S100 calcium-binding protein (S100) a8 and S100a9 were induced more than 5-fold by vildagliptin in the mouse liver. We further examined the effects of vildagliptin and its major metabolite M20.7 on the mRNA expression levels of S100A8 and S100A9 in human hepatoma HepG2 and leukemia HL-60 cells. In HepG2 cells, vildagliptin, M20.7, and sitagliptin - another DPP-4 inhibitor - induced S100A9 mRNA. In HL-60 cells, in contrast, S100A8 and S100A9 mRNAs were significantly induced by vildagliptin and M20.7, but not by sitagliptin. The release of S100A8/A9 complex in the cell culturing medium was observed in the HL-60 cells treated with vildagliptin and M20.7. Therefore, the parental vildagliptin- and M20.7-induced release of S100A8/A9 complex from immune cells, such as neutrophils, might be a contributing factor of vildagliptin-associated liver dysfunction in humans.

Community deworming alleviates geohelminth-induced immune hyporesponsiveness

In cross-sectional studies, chronic helminth infections have been associated with immunological hyporesponsiveness that can affect responses to unrelated antigens. To study the immunological effects of deworming, we conducted a cluster-randomized, double-blind, placebo-controlled trial in Indonesia and assigned 954 households to receive albendazole or placebo once every 3 mo for 2 y. Helminth-specific and nonspecific whole-blood cytokine responses were assessed in 1,059 subjects of all ages, whereas phenotyping of regulatory molecules was undertaken in 121 school-aged children. All measurements were performed before and at 9 and 21 mo after initiation of treatment. Anthelmintic treatment resulted in significant increases in proinflammatory cytokine responses to Plasmodium falciparum-infected red blood cells (PfRBCs) and mitogen, with the largest effect on TNF responses to PfRBCs at 9 mo-estimate [95% confidence interval], 0.37 [0.21-0.53], P value over time (P_time) < 0.0001. Although the frequency of regulatory T cells did not change after treatment, there was a significant decline in the expression of the inhibitory molecule cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) on CD4⁺ T cells of albendazole-treated individuals, -0.060 [-0.107 to -0.013] and -0.057 [-0.105 to -0.008] at 9 and 21 mo, respectively; P_time = 0.017. This trial shows the capacity of helminths to up-regulate inhibitory molecules and to suppress proinflammatory immune responses in humans. This could help to explain the inferior immunological responses to vaccines and lower prevalence of inflammatory diseases in low- compared with high-income countries.

DNA Damage Response Is Involved in the Developmental Toxicity of Mebendazole in Zebrafish Retina

Intestinal helminths cause iron-deficiency anemia in pregnant women, associated with premature delivery, low birth weight, maternal ill health, and maternal death. Although benzimidazole compounds such as mebendazole (MBZ) are highly efficacious against helminths, there are limited data on its use during pregnancy. In this study, we performed in vivo imaging of the retinas of zebrafish larvae exposed to MBZ, and found that exposure to MBZ during 2 and 3 days post-fertilization caused malformation of the retinal layers. To identify the molecular mechanism underlying the developmental toxicity of MBZ, we performed transcriptome analysis of zebrafish eyes. The analysis revealed that the DNA damage response was involved in the developmental toxicity of MBZ. We were also able to demonstrate that inhibition of ATM significantly attenuated the apoptosis induced by MBZ in the zebrafish retina. These results suggest that MBZ causes developmental toxicity in the zebrafish retina at least partly by activating the DNA damage response, including ATM signaling, providing a potential adverse outcome pathway in the developmental toxicity of MBZ in mammals.

A novel cell-based assay for the evaluation of immune- and inflammatory-related gene expression as biomarkers for the risk assessment of drug-induced liver injury

Drug-induced liver injury (DILI) is a major problem in drug development. Although some in vitro methods assessing DILI risk that utilize hepatic cell death or cellular stress as markers have been developed, the predictive ability of these tests is low. In this study, we sought to develop a novel cell-based assay for the risk assessment of DILI that considers drug metabolism as well as immune- and inflammatory-related gene expression. To accomplish this goal, human hepatoma HepaRG or HepG2 cells were treated with 96 drugs with different clinical DILI risks. The conditioned media were subsequently used to treat human promyelocytic leukemia HL-60 cells, and the mRNA expression levels of immune- and inflammatory-related genes in the cells were measured. An area under the receiver operating characteristic curve (ROC-AUC) was calculated to evaluate the predictive performance of the mRNA levels as markers to discriminate DILI risk. The expression of interleukin-8 (IL-8) in HL-60 cells treated with conditioned media from HepaRG cells (HL-60/HepaRG) exhibited the highest ROC-AUC value of 0.758, followed by the expression of IL-1β in HL-60/HepaRG (ROC-AUC: 0.726). Notably, the ROC-AUC values of these genes were higher in HL-60/HepaRG than in HL-60/HepG2, which suggests that HL-60/HepaRG has a higher potential for detecting the metabolic activation of drugs. An integrated score calculated from the levels of S100 calcium-binding protein A9 (S100A9), IL-1β, and IL-8 more precisely determined the DILI risks than individual gene expression did. The developed cell-based assay that utilizes immune-related gene expression would aid in the assessment of potential DILI risks.

Lactobacillus protects the integrity of intestinal epithelial barrier damaged by pathogenic bacteria

Pathogens invade intestinal mucosal barrier through phagocytosis of antigen presenting cells (dendritic cell, microfold cells), or through the invasion into the intestinal epithelial directly. Some pathogens could damage the cell junction between epithelial cells and use the paracellular pathway as an entrance to invade. Moreover, some Lactobacillus could inhibit the adhesion of the pathogens and protect the integrity of the cell junction and mucosal barrier. This research focused on the potential therapeutic effect of Lactobacillus fructosus (L. fructosus) C2 to attenuate ETEC K88 or S. typhimurium SL1344 induced changes to mucosal barrier. The results demonstrated that treatment of polarized Caco-2 cells with L. fructosus C2 reduced the permeation of dextran, and expression of IL-8, p-ERK, and p-JNK when cells were infected with pathogenic bacteria. The findings indicated that L. fructosus C2 exerted a protective effect against the damage to the integrity of Caco-2 cells by ETEC or S. typhimurium infection.

Helminth therapy or elimination: epidemiological, immunological, and clinical considerations

Deworming is rightly advocated to prevent helminth-induced morbidity. Nevertheless, in affluent countries, the deliberate infection of patients with worms is being explored as a possible treatment for inflammatory diseases. Several clinical trials are currently registered, for example, to assess the safety or efficacy of Trichuris suis ova in allergies, inflammatory bowel diseases, multiple sclerosis, rheumatoid arthritis, psoriasis, and autism, and the Necator americanus larvae for allergic rhinitis, asthma, coeliac disease, and multiple sclerosis. Studies in animals provide strong evidence that helminths can not only downregulate parasite-specific immune responses, but also modulate autoimmune and allergic inflammatory responses and improve metabolic homoeostasis. This finding suggests that deworming could lead to the emergence of inflammatory and metabolic conditions in countries that are not prepared for these new epidemics. Further studies in endemic countries are needed to assess this risk and to enhance understanding of how helminths modulate inflammatory and metabolic pathways. Studies are similarly needed in non-endemic countries to move helminth-related interventions that show promise in animals, and in phase 1 and 2 studies in human beings, into the therapeutic development pipeline.

Development of a cell-based assay system considering drug metabolism and immune- and inflammatory-related factors for the risk assessment of drug-induced liver injury

Drug-induced liver injury (DILI) is a major safety concern in drug development and clinical pharmacotherapy. However, prediction of DILI is difficult because the underlying mechanisms are not fully understood. To establish a novel cell-based screening system to suggest drugs with hepatotoxic potential in preclinical drug development, comprehensive gene expression analyses during in vivo DILI are necessary. Using in vivo mouse DILI models and 4 sets of hepatotoxic positive and non-hepatotoxic drugs, we found that the hepatic mRNA levels of S100A8; S100A9; "NATCH, LRR, and pyrin domain-containing protein 3" (NALP3); interleukin (IL)-1β; and the receptor for advanced glycation endproducts (RAGE) were commonly increased in hepatotoxic drug-administered mice compared to non-hepatotoxic drug-administered mice. To clarify whether these 5 in vivo biomarkers can be applied to a cell-based screening system, we adapted human liver microsomes (HLM) in the presence of NADPH to assess the metabolic activation reaction, and we also adapted human monocytic leukemia cells HL-60, K562, KG-1 and THP-1 to assess the effects on mRNA expression of immune- and inflammatory-related factors. We investigated 30 clinical drugs with different safety profiles with regard to DILI and found that the total sum score of gene expression levels of S100A8, S100A9, RAGE, NALP3 and IL-1β mRNA in HL-60 or K562 cells incubated with HLM, could identify drugs at high risk for hepatotoxicity. We proposed the use of the total sum score of gene expression level for assessing metabolic activation by drug-metabolizing enzymes and immune- and inflammatory-related factors for the risk assessment of DILI in preclinical drug development.

Evaluation and mechanistic analysis of the cytotoxicity of the acyl glucuronide of nonsteroidal anti-inflammatory drugs

The chemical reactivity of acyl glucuronide (AG) has been thought to be associated with the toxic properties of drugs containing carboxylic acid moieties, but there has been no direct evidence showing that AG formation is related to the observed toxicity. In the present study, the cytotoxicity of AGs, especially that associated with the inflammatory response, was investigated. The changes in the mRNA and protein expression levels of interleukin 8 (IL-8) and monocyte chemoattractant protein (MCP)-1 induced by the treatment of human peripheral blood mononuclear cells (PBMCs) with diclofenac (Dic), probenecid (Pro), tolmetin (Tol), ibuprofen (Ibu), naproxen (Nap), and their AGs were investigated by real-time reverse transcription polymerase chain reaction, and the viabilities of CD3+, CD14+, and CD19+ cells were measured by flow cytometry. Treatment with Dic-AG, Pro-AG, and Tol-AG significantly increased the expression levels of IL-8 and MCP-1. In addition, Dic-AG, Pro-AG, and Tol-AG significantly decreased the viability of CD14+ cells. Of these three AGs, Dic-AG showed the most potent changes, followed by Tol-AG and Pro-AG. Treatment with Ibu-AG and Nap-AG affected neither the expression levels of IL-8 and MCP-1 nor the viability of CD14+ cells. None of the drugs affected the CD3+ and CD19+ cell populations. Dic-AG increased the phosphorylation of p38 mitogen-activated protein (MAP) kinase and c-Jun N-terminal kinase (JNK)1/2. The pretreatment of peripheral blood mononuclear cells (PBMCs) with SB203580 (p38 inhibitor) significantly suppressed the Dic-AG-induced expression of inflammatory factors and cytotoxicity of CD14+ cells. In conclusion, AGs induce inflammatory responses and cytotoxicity against CD14+ cells via the p38 MAPK pathway. These factors may be useful biomarkers for evaluating the toxicity of AGs.