Critical care involves the management of organismal stress by sedation. Benzodiazepines remain widely used for anxiolysis and sedation in critical care, including in septic shock. Yet converging mechanistic, preclinical and clinical evidence suggests that benzodiazepines and the endogenous ligand of benzodiazepine-binding sites, the “endozepine” acyl-CoA binding protein/diazepam binding inhibitor (ACBP/DBI), may impair host immune defenses, exacerbate organ dysfunction and contribute to long-term morbidity after intensive care. A unifying framework is that benzodiazepines may accelerate “iatrogenic aging” by antagonizing adaptive stress responses (notably autophagy) and favoring cellular senescence, chronic inflammation, immunosuppression and neurocognitive perturbations. Here, we synthesize evidence supporting benzodiazepine avoidance in sepsis-heavy intensive care populations. We propose that replacing benzodiazepines with alternative sedative strategies may improve both short-term outcomes and long-term trajectories of post-sepsis disability. We hypothesize that post-intensive-care syndrome (PICS), including -as a specific case- post-sepsis syndrome (PSS), is caused by premature aging of the organism and that PICS/PSS might be attenuated by the avoidance of benzodiazepine administration during and after critical care.
Triptolide, an extract from the Chinese herb Thunder God Vine, a compound renowned for its anti-cancer properties, exhibits an elusive mechanism of action. While extensive research has elucidated its direct effects on cancer cells, the indirect impact on non-tumor cells within the cancer microenvironment remains poorly understood. In this study, we investigated the influence of Triptolide on tumor-associated macrophages (TAMs), pivotal contributors to ovarian cancer progression. Using cell culture and promoter assay, cellular viability assessment, cell clock assay, transwell assays, flow cytometry, ELISA, TUNEL staining, and mouse models, we found that Triptolide does not significantly affect macrophage proliferation or survival; instead, it induces differentiation of naive macrophages towards the M1 phenotype and reprograms M2-polarized macrophages into a similar inflammatory state. These observations suggest that modulation of TAMs may partially underlie Triptolide’s hindrance of ovarian cancer progression. Mechanistically, we reveal that Triptolide inhibits Nrf2 transcription - a master regulator governing anti-inflammatory responses in macrophages. Functional gain- and loss-of-function studies further confirmed that Nrf2 inhibition is essential for Triptolide-mediated TAM reprogramming and subsequent suppression of cancer cell progression. Co-culturing with macrophages substantially enhances ovarian cancer cell growth, invasion, and migration; however, all these effects are abrogated by treatment with Triptolide. Collectively, our findings indicate that the suppression of ovarian cancer by Triptolide is mediated in part through its capacity to reprogram TAMs via the Nrf2 pathway.
Geroprotection aims at extending healthspan by delaying age-associated pathologies. Polyamines including spermine and spermidine are interconvertible metabolites whose longevity-promoting effects have traditionally been attributed to autophagy induction. In addition, recent evidence identifies spermine as an endogenous Fe2+ chelator that suppresses ferroptosis, thereby complementing the autophagy-inducing activity of spermidine. Indeed, spermidine inhibits EP300 acetyltransferase activity and supports hypusination-dependent activation of TFEB, both leading to autophagy. However, enhanced autophagic flux may increase susceptibility to ferroptosis through ferritinophagy and lipid remodeling. In parallel, polyamine catabolism generates H2O2 and acrolein, both of which facilitate lipid peroxidation and ferroptotic demise. The discovery that spermine directly chelates redox-active Fe2+ closes a conceptual gap by explaining how polyamine supplementation can promote longevity while avoiding excessive ferroptotic cell loss. Multiple lines of evidence including metabolomics, isotope tracing, cell-free lipid peroxidation systems, Fe2+-binding biophysics, mass spectrometry, Raman spectroscopy, nuclear magnetic resonance and disease models demonstrate that spermine limits labile iron and ferroptosis. Together, these findings support a unified model in which spermidine-driven autophagy and spermine-mediated ferroptosis inhibition cooperate to preserve tissue homeostasis and healthspan.
Arachidonic acid (AA) metabolism plays a critical role in renal cell osmoadaptation. We recently demonstrated that hypertonicity induces the expression and activation of cytosolic phospholipase A2 (cPLA2). On one hand, AA released by cPLA2 enhances triacylglyceride (TG) synthesis and accumulation. On the other hand, AA is converted into prostaglandins (PG) through cyclooxygenase 2 (COX2) activity. Both processes are required for renal cell survival under osmotic stress. However, the mechanisms by which hypertonicity induces cPLA2 expression remain poorly understood. Given that we previously shown that hypertonicity regulates TG synthesis through the IRE1α-XBP1s branch of the unfolded protein response (UPR), here we examined whether XBP1s regulates the cPLA2-AA-COX2 axis in renal cells subjected to osmotic stress. We found that XBP1s modulates hypertonicity-induced expression of cPLA2 and COX2 by increasing NFκB transcriptional activity. Inhibition of IRE1α impaired normal COX2 degradation and disrupted AA metabolism, leading to a decrease in cell viability and preventing hypertonicity-induced epithelial differentiation. Prostaglandin E2 (PGE2) contributed to cell polarization facilitating adherens junction (AJ) assembly. Together, these findings highlight a central role for the IREα-XBP1s-NFκB signaling axis in coordinating cell stress responses and epithelial differentiation through AA metabolism activation.
Canopy homolog protein 2 (CNPY2), an endoplasmic reticulum (ER) luminal protein exhibits broad tissue distribution and regulates cellular homeostasis, including unfolded protein responses (UPR), mitochondrial dynamics, oxidative stress, and apoptosis. Beyond its role in cancer progression through pathways such as NF-κB, AKT/GSK3β, PI3K/Akt/mTOR and HIF-1α, promoting epithelial-mesenchymal transition (EMT), tumor survival and metastasis, CNPY2 is also critical in non-cancer conditions. In neurodegenerative disorders including Parkinson’s and Huntington’s, it exerts neuroprotective role by reducing oxidative stress and mitochondrial dysfunction. In cardiovascular tissues, CNPY2 leads to hypoxia-driven angiogenesis, tissue repair, and ischemia-reperfusion protection. Moreover, recent meta-analyses have linked CNPY2 downregulation with Keratoconus pathogenesis, further highlighting its tissue- specific roles. Hence, this review meticulously dissects CNPY2’s structural characteristics, expression patterns, and biological functions across cancer, cardiovascular disease, inflammation and neurological disorders, emphasizing its role on tumor initiation, microenvironmental stress, and chemoresistance, and evaluating its potential as a therapeutic target.
Fungal infections pose a significant global health threat with rising morbidity and mortality rates. However, the repertoire of effective antifungal drugs remains narrow, a challenge that is further exacerbated by the increasing emergence of (multi)drug-resistant strains. This underscores the urgent need for novel therapeutic strategies. Among them, antifungal peptides (AFPs) have emerged as a promising alternative. AFPs are small, naturally occurring peptides produced by a wide range of organisms, including plants, animals, fungi, and bacteria, as part of their innate immune defense. In addition, synthetic and semisynthetic variants have also been engineered. We here underscore the potential of AFPs as viable candidates for the development of next-generation antifungal therapies. In particular, we advocate their multimodal advantage that spans beyond standalone activity, including their synergistic and immune-regulatory potential.
Cushing syndrome (CS) is caused by an increase in endogenous or exogenous glucocorticoids, leading to major alterations in body composition, including visceral obesity, sarcopenia, osteoporosis, type 2 diabetes, and dyslipidemia. Cardiovascular complications resulting from CS are often lethal. We previously demonstrated that CS induced by oral corticosterone (CORT) supplementation in mice can be prevented by inhibition of the peptide hormone acyl-CoA binding protein (ACBP), encoded by the gene diazepam binding inhibitor (DBI). Here, we investigated whether ACBP/DBI inhibition could be used to treat, rather than prevent, CS. To this end, we initiated treatment with anti-ACBP/DBI monoclonal antibodies (mAbs) in mice three weeks after the start of CORT supplementation, when hyperphagia and body weight gain were already established. Two anti-ACBP/DBI mAbs, 7G4a (specific for mouse ACBP/DBI only) and 82 (which recognizes both mouse and human ACBP/DBI), were able to normalize food intake and halt weight gain in mice under continuous CORT treatment. In addition, both mAbs attenuated CORT-induced sarcopenia, adiposity in inguinal, perigonadal, and visceral fat depots, and fully restored metabolic parameters, including type-2 diabetes, insulinemia, free fatty acids, triglycerides, and liver transaminases. In conclusion, neutralization of ACBP/DBI may serve as an effective therapeutic strategy for the treatment of established CS.
Removing certain essential amino acids from the diet is known to promote weight loss in rodents via effects on food intake and energy expenditure. Two complementary articles by Varghese et al [Nature 643(8072)] and Lee et al [Nature Metabolism 7(6)] now show that cysteine depletion through combined dietary and genetic means in mice evokes a unique stress response in the liver to amplify these metabolic outcomes and offer a potentially new treatment option for obesity.
The dysfunction of mitochondria, the "energy factories" of cells, not only causes an insufficiency of energy production but also leads to various pathological alterations in cells such as the accumulation of reactive oxygen species, inflammatory responses and mitochondrial DNA damage, all of which were involved in the onset or deterioration of diseases. The presence of mitochondrial dysfunction has been confirmed in many ocular surface diseases such as dry eye, Fuchs corneal endothelial dystrophy and diabetic keratopathy. However, its role in the pathogenesis of ocular surface diseases and underlying molecular mechanisms have not been fully elucidated. Moreover, mitochondrial therapies for ocular surface diseases are currently still under investigation. This mini-review summarizes the pathological features of mitochondrial dysfunction and its mechanisms that have been identified in the pathogenesis of ocular surface diseases, and discusses the potential of mitochondrial therapies in the treatment of these diseases.
Antibody-drug conjugates (ADCs) offer a strategy for targeted delivery of cytotoxic agents to cancer cells. In this study, we investigated the mechanism of action of datopotamab deruxtecan, an ADC composed of a monoclonal antibody targeting tumor-associated calcium signal transducer 2 (TACSTD2, also known as trophoblast cell-surface antigen-2 (TROP2)) conjugated to the topoisomerase I inhibitor DXd. Datopotamab deruxtecan reduced the viability of human osteosarcoma U2OS cells engineered to express TROP2, but had no effect on their parental counterparts, which only expressed the CALR-GFP biosensor. In TROP2-expressing cells, it triggered the translocation of CALR-GFP from the ER to the cell periphery. Both datopotamab deruxtecan and its DXd payload elicited several features characteristic of immunogenic cell death (ICD), including detectable calreticulin exposure on the cell surface, release of high-mobility group box 1 (HMGB1), and ATP secretion into the culture medium. Importantly, the TROP2-targeted ADC also exerted a bystander antitumor effect on parental U2OS cells (lacking TROP2 expression) co-cultured with TROP2-expressing U2OS cells. These findings demonstrate that datopotamab deruxtecan delivers a cytotoxic payload capable of inducing hallmark features of ICD in vitro.
An imbalanced production of reactive oxygen species (ROS) is linked to various aspects of cancer development, including cytoskeletal remodelling. However, the relationship between ROS, actin and cellular stiffness remains controversial. Here, we show that oxidative stress increases cortical stiffness in pre-apoptotic colon and pancreatic cancer cells via localized F-actin polymerization in the apical cortex — independent of changes in total F-actin levels. Using atomic force microscopy and flow cytometry, we demonstrate this effect across multiple ROS inducers: the combination of arsenic trioxide and D-enantiomer of vitamin C, hydrogen peroxide, and rotenone. These findings explain previously debated relationships on how ROS influence actin organization, which may affect cellular stiffness. By separating total from cortical actin effects, our study reveals a redox-sensitive mechanism that governs cytoskeletal remodelling and may impair cancer cell migration.
High carbohydrate intake, a characteristic of many Western diets, is a major contributor to age-associated pathologies. Here, we explored the molecular consequences of sugar overload during chronological aging in the yeast Saccharomyces cerevisiae. High levels of glucose and fructose resulted in a decrease of chronological lifespan as well as an increase of cell death, ROS and neutral lipids. Interestingly, these changes were accompanied by significantly altered ceramide profiles. Deletion of either the kinase Tor1, a master regulator of growth and autophagy in response to nutrients, or the vacuole-anchored receptor Vac8, an important player in various autophagy pathways, improved survival and normalized ceramide profiles. This suggests that ceramides might play a role in sugar stress-induced cell death. In line, pharmacological inhibition of sphingolipid synthesis normalized ceramide profiles and improved chronological lifespan, whereas pharmacologically induced ceramide accumulation decreased chronological lifespan. In sum, our findings causally link nutrient signaling and an altered ceramide profile to sugar cytotoxicity in aging yeast, providing a basis for further search of feasible interventions against sugar-induced cell death.
Replication stress (RS) is a major driver of genomic instability and cancer development through impaired DNA replication that can lead to chromosomal instability (CIN). Although RS is mechanistically linked to CIN, its relationship with cellular proliferation is complex. Depending on the context, RS can either promote or suppress cell growth. Existing RS gene expression signatures overlook this complexity, relying on the overexpression of oncogenes such as MYC, which introduces a proliferation bias. To disentangle genuine RS from confounding cell cycle and proliferation transcriptional profiles, we developed and validated a novel gene expression signature that accurately predicts RS independently of oncogene activity. This tumorigenic RS signature (TRSS) captures RS-related transcriptional changes across diverse cellular contexts, enabling a more robust and proliferation-independent measure of RS in both experimental and clinical samples. Applying our signature to patient data, we discovered a link between RS and the non-homologous end-joining (NHEJ) DNA repair pathway. Specifically, we observed that MSH2 and MSH6 - core components of mismatch repair - are associated with elevated RS and may indicate a shift toward NHEJ-mediated repair under stress conditions. Our study provides a refined approach to quantify RS and sheds light on its broader impact on DNA repair network dynamics.
Genetically identical cells in a population show cell-to-cell variability because of fluctuation in transcription, epigenetics, post-translational modifications, and stochastic or extrinsically triggered non-genetic alterations. The change in the interaction state of proteins also emerges as an additional layer of cell signaling that influences cell cycle and cell death. However, the interrelation between cell cycle progression and cell death under the influence of spatio-temporal changes in protein-protein interaction is difficult to demonstrate in growing cells. This requires tools for cell cycle phase-resolved visualization of macromolecular interactions in live cells. We describe an approach to visualize the interaction of pro- and anti-death signaling partners, Bax and Bcl-xL, during cell cycle progression and cell death in live cells. Cells were stably expressed with Bax and Bcl-xL with FRET pairs and real-time cell cycle indicator probes. Acceptor photobleaching and Fluorescence lifetime imaging revealed interaction dynamics between Bax and Bcl-xL in isogenic stable cells. While Bcl-xL inhibited cell cycle progression, Bax promoted the cell cycle. The study highlighted an increased Bax-Bcl-xL interaction in the G1 phase compared to the non-G1 phase. Increased interaction is seen under stressed conditions and Bax-activated cells with FLIM-FRET, highlighting the nature of Bax-Bcl-xL interaction during cellular stress. In conclusion, our study explains Bax-Bcl-xL interaction dynamics in real-time and the potential utility of the approach to study macromolecular interactions along with cell cycle and cell death.
Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly referred to non-alcoholic fatty liver disease (NAFLD), has become a global health concern with a still increasing prevalence. One of the major contributing factors to its pathogenesis is overnutrition. In recent years, a discussion has been started that not only general overnutrition but also specific dietary patterns like the so-called 'Western diet' composed of foods rich in saturated fats, cholesterol, and sugar (especially fructose) but low in fiber and polyunsaturated fats, may contribute to the development of MASLD. Evidence from human (intervention) studies regarding the effects of sugar and especially fructose intake is limited and contradictory with respect to the development of MASLD. Still, some scientific liver societies have incorporated a reduction of sugar-sweetened beverages (SSBs) being rich in fructose in their life-style advice for the treatment of MASLD. Being metabolized independently of insulin, fructose has been proposed to be processed more rapidly than glucose, leading to increased lipogenesis and subsequently to hepatic lipid accumulation. Results of more recent experimental studies suggest that an elevated intake of fructose may also affect gut microbiota composition, alter small intestinal morphology and impair intestinal barrier function subsequently leading to an increased translocation of pathogen-associated molecular patterns (PAMPs) into the portal circulation. In this narrative review we summarize recent findings related to the relationship of fructose intake and MASLD, herein focusing on the gut-liver axis and the discrepancy between studies in humans and model organisms.
Nuclear factor of activated T cells 5 (NFAT5) is a transcription factor within the Rel family, primarily recognized for its role in cellular adaptation to osmotic stress, particularly in hypertonic and hyperosmotic environments. Beyond osmotic regulation, NFAT5 responds to diverse stimuli, including cytokines, growth factors, oxidative stress, and microbial signals. This versatility enables NFAT5 to regulate essential cellular processes such as proliferation, survival, migration, and vascular remodelling. In the immune system, NFAT5 modulates the function of monocytes, macrophages, astrocytes, microglia, and T cells, contributing to immune homeostasis and inflammatory responses. Dysregulation of NFAT5 activity is implicated in various pathological conditions, including autoimmune diseases, cancer, and cardiovascular disorders, largely due to its ability to control genes involved in inflammatory and immune pathways under both isotonic and hypertonic conditions. Recent studies have unveiled new regulatory mechanisms, including interactions with non-coding RNAs, offering deeper insights into the functional landscape of NFAT5 and its therapeutic potential. This review delves into the multifaceted roles of NFAT5 in health and disease, emphasizing its emerging importance as a promising therapeutic target.
The human gut microbiota, a diverse community of beneficial normal flora microorganisms, significantly influences physiological function and the immune response. Various microbiota strains have shown promise in supporting clinical treatment of chronic diseases, including cancer, by potentially providing antioxidative and anti-tumorigenic effects in both in vivo and in vitro studies. Breast cancer, which ranks amongst the top five cancer types common worldwide and particularly in Mediterranean countries, has been showing high incidence and prevalence. In breast cancer, microbiota composition, hormonal dynamics, and dietary choices are believed to play significant roles. Hence, the Mediterranean diet, known for its microbiota-friendly features, emerges as a potential protective factor against breast cancer development, highlighting the potential for personalized dietary strategies in cancer prevention. This comprehensive review highlights the emerging mechanisms by which probiotics support our immune system during different physiological activities. It also discusses their potential role, along with nutrition intervention, in improving essential clinical treatment outcomes in breast cancer patients and survivors, suggesting potential supportive strategies that go hand in hand with clinical strategies. Unfortunately, very little research addresses the possible clinical implications of probiotics and dietary habits on breast cancer, despite the promising results, calling for further studies and actions.
Differential and even opposing functions of two major antioxidant transcription factors Nrf1 and Nrf2 (encoded by Nfe2l1 and Nfe2l2, respectively) are determined by distinctions in their tempospatial positioning, topological repartitioning, proteolytic processing, and biochemical modification, as well as in their shared evolutionary origin. As a matter of fact, the allelopathic potentials of Nrf1 and Nrf2 (both resembling two entangled ‘Yin-Yang’ quanta that comply with a dialectic law of the unity of opposites) are fulfilled to coordinately control redox physiological homeostasis so as to be maintained within the presetting thresholds. By putative exponential curves of redox stress and intrinsic anti-redox capability, there is inferable to exist a set point at approaching zero with the ‘Golden Mean’ for the healthy survival (i.e., dubbed the ‘zero theory’). A bulk of the hitherto accumulating evidence demonstrates that the set point of redox homeostasis is dictated selectively by multi-hierarchical threshold settings, in which the living fossil-like Nrf1 acts as a robust indispensable determinon, whereas Nrf2 serves as a versatile chameleon-like master regulon, in governing the redox homeodynamic ranges. This is attributable to the facts that Nrf2 has exerted certain ‘double-edged sword’ effects on life process, whereas Nrf1 executes its essential physiobiological functions, along with unique pathophysiological phenotypes, by integrating its ‘three-in-one’ roles elicited as a specific triplet of direct sensor, transducer and effector within multi-hierarchical stress responsive signaling to redox metabolism and target gene reprogramming. Here, we also critically reviewed redox regulation of physio-pathological functions from the eco-evo-devo perspectives, through those coding rules (redox code, stress-coping code, and topogenetic code). The evolving concepts on stress and redox stress were also further revisited by scientific principles of physics and chemistry. Besides, several novel concepts such as oncoprotists, Reverse Central Dogma, and Grand Redox-Unifying Theory’ (GRUT) of life, together with diffusive reactive species (DRS)-based murburn concept integrating all stochastic electron-, proton- and/or moiety-transfer reactive and interactive processes (e.g., PCHEMS), are introduced in this interdisciplinary and synthetic review.
Cold exposure has been historically used for medicinal purposes, but its benefits and associated mechanisms in mammalian organisms still remain unclear. Here , we explore the chemoprotective properties of cold temperature using a mouse model of hepatocellular carcinoma (HCC) that recapitulates several human features. Chronic cold exposure is shown to prolong lifespan in diseased mice, enhance liver health, and suppress the development of aggressive HCC , preventing hepatocellular hypertrophy, high-grade oval cell hyperplasia, liver steatosis, and aberrant hepatocyte hyperproliferation. Mechanistically, exposure to cold temperatures reinstates NAD + levels in the HCC mouse model s that originally exhibited low NAD + levels , a contributing process to the development of liver tumors. These findings uncover the role of cold therapy to attenuate HCC development and potentially other existing malignancies involving NAD + modulation.
Human peripheral blood mononuclear cells (PBMCs) are used to examine biological processes and disease, when basal variability in cellular activation and splicing is described and unexplained. Using isolation systems that maintained buffy coat cells (PBMCs, platelets) in their own plasma, poly-A enriched RNA-sequencing (RNASeq) detected 42,720 Ensembl gene IDs, including >95% of the top 100 Genotype Tissue Expression Project (GTEx)-expressed genes in lung, colon, heart, skeletal muscle and liver, and 10/17 clinically-actionable genes listed by the Pharmacogenomics Knowledgebase. Transcriptome changes were defined after 1h treatment with 32°C hypothermia (hsp70 family member change), 10 μmol/L ferric citrate that had no discernible effect, and 100 μg/mL cycloheximide leading to induction of primary response (immediate early) genes including IL1B and TNF. Same-donor PBMCs prepared conventionally using washes then resuspension in serum-supplemented media demonstrated basal upregulation of stress signalling pathway genes that masked and overlapped differential gene expression profiles after 100 µg/L cycloheximide. Plasma-resuspended PBMCs demonstrated minor transcriptome changes after 40 μmol/L ferric citrate, whereas consistent and greater magnitude changes were observed for washed/media-resuspended PBMCs. We conclude that endogenous plasma-maintained PBMCs provide a more robust platform to interrogate acute cellular perturbations triggering innate immunity, and that varying susceptibility of PBMCs to preparative stresses is an important component of experimental variability.
