Methotrexate in pregnancy: still many unanswered questions

In vitro embryolethality testing during the peri-implantation stage using 3D mouse embryoids: Comparison with 2D mouse cell cultures and the zebrafish embryo model

The recent development of in vitro embryoid models may be a way to reduce or even replace animals in developmental and reproductive toxicity (DART) studies. Here, we evaluated an in vitro mouse 3D embryoid model using three stem cell lineages including mouse embryonic stem cells (ESC), trophoblast stem cells (TSC) and extra-embryonic endoderm stem cells (XENC) to detect embryolethality of seven known positive or negative compounds at the peri-implantation stage in vivo. We performed a comparative study by testing these substances in parallel on monocultures of the individual cell lines in 2D and in zebrafish embryos. Embryoids were exposed to each compound for 48 h and analysed on day in vitro (DIV) 4, which resemble the peri-implantation embryo at E5.5 in vivo. Metabolic activity, morphological development and gene expression were evaluated. We showed that all early direct embryolethal compounds significantly reduced the metabolic activity of the embryoids at an in vivo relevant concentration range. Furthermore, this model could also detect embryolethal compounds that have specific adverse effects on extraembryonic structures. The additional endpoints (gene expression or morphological assessments) were required to detect adverse effects when only a minoritarian cell type of the embryoid was affected. In contrast, zebrafish embryos had a very low sensitivity, and the monocultures of the individual cell lines were less specific than the 3D embryoids. Combining 2D and 3D testing with carefully selected additional endpoints could serve as a powerful tool to assess the potential effects of new chemicals on embryo development at the peri-implantation stage.

Methotrexate-induced disruption of the serum-glucocorticoid inducible protein kinase 3 signaling pathway and its effects on brain development

Methotrexate (MTX) is a widely used chemotherapeutic and immunosuppressive agent. It is frequently detected in the environment due to its low biodegradability and toxic properties, which may pose risk to humans via contaminated drinking water. MTX impacts brain development; however, the underlying mechanisms remain poorly understood. In this study, we aimed to investigate the potential of brain cortical organoids (COs) to exhibit developmental neurotoxicity upon exposure to MTX and elucidated the underlying mechanisms. We showed that MTX affected brain development by increasing reactive oxygen species production, endoplasmic reticulum stress, and apoptosis in COs, affecting immature neurons, gamma-aminobutyric acid (GABA)ergic neurons, and astrocytes. Treatment with folic acid ameliorated the MTX-induced cellular damage. Furthermore, RNA-seq analysis revealed the significant downregulation of serum/glucocorticoid-regulated kinase family member 3 (SGK3) by MTX treatment. Further investigation using RNA interference with an siRNA targeting SGK3 confirmed that the SGK3 signaling pathway plays an essential role in regulating brain development. Finally, we demonstrated calcium homeostasis disruption in MTX-treated COs (MTX-COs). Our findings suggest that MTX affects cortical development in the brain by increasing intracellular ROS and ER stress, ultimately inducing apoptosis through the inhibition of the SGK3 signaling pathway in MTX-COs. Furthermore, abnormal brain development can be caused by an imbalance in intracellular calcium homeostasis and alterations in the neuronal cell expression in MTX-COs. These results indicate that MTX causes developmental neurotoxicity and underscore the importance of informed decision making regarding the clinical use of MTX, particularly during pregnancy.

Low-dose methotrexate in Rheumatology: A reinvented drug

Low-dose methotrexate (LD-MTX) is the anchor drug used in the treatment of various rheumatological illnesses. There are a lot of misconceptions associated with the long-term use of MTX in the minds of practitioners. The origin of most of these myths stems from the ill effects associated with high-dose MTX used in cancer chemotherapy. In this review, we have summarised and discussed the latest data regarding the safety of LD-MTX. The current evidence underscores the safety of LD-MTX. It is not associated with liver and lung fibrosis as previously thought. Other major concerns such as bone marrow suppression and increased risk of infection are rare with chronic LD-MTX therapy. Hypersensitivity pneumonitis is a rare acute lung toxicity associated with MTX intake, it does not cause interstitial lung disease and in fact, may be protective against it. There is a slight concern about the increased risk of skin malignancy associated with MTX intake; however, association with no other malignancy has been found. It has taken many decades for researchers to clear the various preconceptions associated with MTX. It is time for the academic community to embrace LD-MTX as a new, separate and reinvented drug.

Methotrexate for the neurologist

The use of methotrexate in clinical practice has expanded significantly in recent years, as an effective chemotherapeutic agent as well as disease-modifying treatment for conditions such as rheumatoid arthritis, psoriasis and Crohn's disease. It is also used as a steroid-sparing agent for a range of inflammatory diseases of the central and peripheral nervous systems. Clinical neurologists must, therefore, know how to start and uptitrate methotrexate, its monitoring requirements and its potential toxicities. This review aims first to explore the evidence base for using methotrexate in various neurological diseases and second to discuss important practicalities around its use, ensuring its safe application and appropriate monitoring.

Assessing the accuracy and completeness of artificial intelligence language models in providing information on methotrexate use

We aimed to assess Large Language Models (LLMs)-ChatGPT 3.5-4, BARD, and Bing-in their accuracy and completeness when answering Methotrexate (MTX) related questions for treating rheumatoid arthritis. We employed 23 questions from an earlier study related to MTX concerns. These questions were entered into the LLMs, and the responses generated by each model were evaluated by two reviewers using Likert scales to assess accuracy and completeness. The GPT models achieved a 100% correct answer rate, while BARD and Bing scored 73.91%. In terms of accuracy of the outputs (completely correct responses), GPT-4 achieved a score of 100%, GPT 3.5 secured 86.96%, and BARD and Bing each scored 60.87%. BARD produced 17.39% incorrect responses and 8.7% non-responses, while Bing recorded 13.04% incorrect and 13.04% non-responses. The ChatGPT models produced significantly more accurate responses than Bing for the "mechanism of action" category, and GPT-4 model showed significantly higher accuracy than BARD in the "side effects" category. There were no statistically significant differences among the models for the "lifestyle" category. GPT-4 achieved a comprehensive output of 100%, followed by GPT-3.5 at 86.96%, BARD at 60.86%, and Bing at 0%. In the "mechanism of action" category, both ChatGPT models and BARD produced significantly more comprehensive outputs than Bing. For the "side effects" and "lifestyle" categories, the ChatGPT models showed significantly higher completeness than Bing. The GPT models, particularly GPT 4, demonstrated superior performance in providing accurate and comprehensive patient information about MTX use. However, the study also identified inaccuracies and shortcomings in the generated responses.

Pralatrexate inhibited the replication of varicella zoster virus and vesicular stomatitis virus: An old dog with new tricks

Varicella zoster virus (VZV) is associated with herpes zoster (HZ) or herpes zoster ophthalmicus (HZO). All antiviral agents currently licensed for the management of VZV replication via modulating different mechanisms, and the resistance is on the rise. There is a need to develop new antiviral agents with distinct mechanisms of action and adequate safety profiles. Pralatrexate (PDX) is a fourth-generation anti-folate agent with an inhibitory activity on folate (FA) metabolism and has been used as an anti-tumor drug. We observed that PDX possessed potent inhibitory activity against VZV infection. In this study, we reported the antiviral effects and the underlying mechanism of PDX against VZV infection. The results showed that PDX not only inhibited VZV replication in vitro and in mice corneal tissues but also reduced the inflammatory response and apoptosis induced by viral infection. Furthermore, PDX treatment showed a similar anti-VSV inhibitory effect in both in vitro and in vivo models. Mechanistically, PDX inhibited viral replication by interrupting the substrate supply for de novo purine and thymidine synthesis. In conclusion, this study discovered the potent antiviral activity of PDX with a novel mechanism and presented a new strategy for VZV treatment that targets a cellular metabolic mechanism essential for viral replication. The present study provided a new insight into the development of broad-spectrum antiviral agents.

Saudi consensus guidance for the management of inflammatory bowel disease during pregnancy

ABSTRACT

The management of inflammatory bowel disease (IBD) in pregnant women is challenging and must be addressed on a patient-by-patient basis. Optimal patient management requires a multidisciplinary team and clear evidence-based recommendations that cater to this subset of patients. In this article, we provide concise guidelines and clinical care pathway for the management of IBD in pregnant women. Our recommendations were developed by a multidisciplinary working group that includes experts from the Saudi Ministry of Health in collaboration with the Saudi Gastroenterology Association and the Saudi Society of Clinical Pharmacology. All recommendations are based on up-to-date information following an extensive literature review. A total of 23 evidence-based expert opinion recommendations for the management of IBD in pregnant women are herein provided.