The Potential Role of Regulated Cell Death in Dry Eye Diseases and Ocular Surface Dysfunction.

The research on new treatments for dry eye diseases (DED) has exponentially grown over the past decades. The increased prevalence of dry eye conditions, particularly in the younger population, has received much attention. Therefore, it is of utmost importance to identify novel therapeutical targets. Regulated cell death (RCD) is an essential process to control the biological homeostasis of tissues and organisms. The identification of different mechanisms of RCD stimulated the research on their involvement in different human pathologies. Whereas apoptosis has been widely studied in DED and included in the DED vicious cycle, the role of RCD still needs to be completely elucidated. In this review, we will explore the potential roles of different types of RCD in DED and ocular surface dysfunction. Starting from the evidence of oxidative stress and inflammation in dry eye pathology, we will analyse the potential therapeutic applications of the following principal RCD mechanisms: ferroptosis, necroptosis, and pyroptosis.

Boosting the Impact of EFMC Young Scientists Network Through the Creation of Working Groups.

The establishment of the Young Scientists Network (YSN) by the European Federation for Medicinal Chemistry (EFMC) served as a proactive response to the evolving landscape of the scientific community. The YSN aims to assist early-career medicinal chemists and chemical biologists by responding to emerging themes, such as the influence of social media, shifts in gender balance within the scientific population, and evolving educational opportunities. The YSN also ensures that the upcoming generation of scientists actively contributes to shape the EFMC's strategic direction while addressing their specific needs. Initially conceived as a general concept, YSN has evolved into a proactive and dynamic team which demonstrates a tangible impact. To boost the impact of the YSN and involve additional motivated young scientists, we have adopted a novel organization, and structured the team in seven working groups (WGs). Herein, we will discuss the tasks of the different WGs as well as the activities planned for the near future. We believe this structure will strengthen the pivotal role YSN has already played in serving medicinal chemists and chemical biologists in Europe. The YSN now has the structure and motivation to pave the way to attract young scientists across Europe and to give them the stage within EFMC.

Beyond ferrostatin-1: a comprehensive review of ferroptosis inhibitors.

Ferroptosis is an iron-catalysed form of regulated cell death, which is critically dependent on phospholipid peroxidation of cellular membranes. Ferrostatin 1 was one of the first synthetic radical-trapping antioxidants (RTAs) reported to block ferroptosis and it is widely used as reference compound. Ferroptosis has been linked to multiple diseases and the use of its inhibitors could have therapeutic potential. Although, novel biochemical pathways provide insights for different pharmacological targets, the use of lipophilic RTAs to block ferroptosis remains superior. In this Review, we provide a comprehensive overview of the different classes of ferroptosis inhibitors, focusing on endogenous and synthetic RTAs. A thorough analysis of their chemical, pharmacokinetic, and pharmacological properties and potential for in vivo use is provided.

From PERK to RIPK1: Design, synthesis and evaluation of novel potent and selective necroptosis inhibitors.

Receptor-Interacting serine/threonine-Protein Kinase 1 (RIPK1) emerged as an important driver of inflammation and, consequently, inflammatory pathologies. The enzymatic activity of RIPK1 is known to indirectly promote inflammation by triggering cell death, in the form of apoptosis, necroptosis and pyroptosis. Small molecule Receptor-Interacting serine/threonine-Protein Kinase 1 inhibitors have therefore recently entered clinical trials for the treatment of a subset of inflammatory pathologies. We previously identified GSK2656157 (GSK'157), a supposedly specific inhibitor of protein kinase R (PKR)-like ER kinase (PERK), as a much more potent type II Receptor-Interacting serine/threonine-Protein Kinase 1 inhibitor. We now performed further structural optimisation on the GSK'157 scaffold in order to develop a novel class of more selective Receptor-Interacting serine/threonine-Protein Kinase 1 inhibitors. Based on a structure-activity relationship (SAR) reported in the literature, we anticipated that introducing a substituent on the para-position of the pyridinyl ring would decrease the interaction with PERK. Herein, we report a series of novel GSK'157 analogues with different para-substituents with increased selectivity for Receptor-Interacting serine/threonine-Protein Kinase 1. The optimisation led to UAMC-3861 as the best compound of this series in terms of activity and selectivity for Receptor-Interacting serine/threonine-Protein Kinase 1 over PERK. The most selective compounds were screened in vitro for their ability to inhibit RIPK1-dependent apoptosis and necroptosis. With this work, we successfully synthesised a novel series of potent and selective type II Receptor-Interacting serine/threonine-Protein Kinase 1 inhibitors based on the GSK'157 scaffold.

Therapeutic modulators of the serotonin 5-HT4 receptor: a patent review (2014-present).

INTRODUCTION: Numerous chemotypes have been described over time in order to generate potent and selective 5-HT4R ligands. Both agonists and antagonists have demonstrated their interest in several disease models. This culminates with the FDA approval of tegaserod and prucalopride in the recent years. AREAS COVERED: This review summarizes the patent applications from 2014 to present, dedicated to the use or the description of novel 5-HT4R modulators. Several novel ligands and scaffolds have been industrially protected mainly in the field of central nervous system (CNS) pathologies as well as gastrointestinal disorders, including the combination with other drugs or for veterinary uses. EXPERT OPINION: The therapeutic potential of 5-HT4R modulators has been explored for several years in animal models, but also linked to potential safety issues with initial ligands. The current use of prucalopride in humans demonstrates that its toxicity is not linked to the target and that 5-HT4R modulators are safe in humans. Therefore, an important number of studies and patents has continued in the recent years to expand the use of 5-HT4R modulators, not only to treat gastrointestinal disorders, but also for CNS pathologies. This article details current efforts in this development.

Novel multi target-directed ligands targeting 5-HT4 receptors with in cellulo antioxidant properties as promising leads in Alzheimer's disease.

Facing the complexity of Alzheimer's disease (AD), it is now currently admitted that a therapeutic pleiotropic intervention is needed to alter its progression. Among the major hallmarks of the disease, the amyloid pathology and the oxidative stress are closely related. We propose in this study to develop original Multi-Target Directed Ligands (MTDL) able to impact at the same time Aß protein accumulation and toxicity of Reactive Oxygen Species (ROS) in neuronal cells. Such MTDL were obtained by linking on a central piperidine two scaffolds of interest: a typical aminochlorobenzophenone present in numerous 5-HT4R agonists, and diverse antioxidant chemotypes. Interestingly, the most active compound 9g possesses a Ki of 12.7 nM towards 5-HT4R and an antioxidant activity in vitro and in cellulo.