Biology subjects

Trejo, J. L.

Publications and source records attributed to Trejo, J. L..

5 recordsLinked to original sources

bioRxiv2025

An anti-amyloidogenic approach to specifically block memory consolidation in mice for therapeutic intervention

Post-traumatic stress disorder (PTSD) is a mental health disorder triggered by the exposure to a traumatic event, which manifests with anguish, intrusive memories, and negative mood changes. So far, there is no efficient treatment for PTSD other than symptomatic palliative care. However, the cytoplasmic polyadenylation element binding protein-3 (CPEB3) has been recently associated to a potential risk gene for PTSD. Considering that CPEB3 protein is a functional amyloid whose importance for long-term memory consolidation in mammals is well established, we propose the active (amyloid) state of CPEB3 as a promising therapeutic target to block the consolidation of traumatic memories through by the anti-amyloidogenic polyglutamine binding peptide 1 (QBP1). Here we report a preclinical development in mice of this pharmacological treatment for PTSD based on the action of the QBP1 peptide. We first characterized the human CPEB3 (hCPEB3) protein in vitro, showing how its amyloid aggregation is inhibited by the active core of QBP1 (QBP1-M8) without affecting other self-assembly processes such as phase separation. Then, we generated and characterized a novel transgenic mouse that constitutively expresses QBP1 in tandem (TgQBP1). TgQBP1 mice have shown that the consolidation of simple learning is impaired after 24 h for both hippocampal-dependent and aversive memories and that it is limited to new learned memories and has no effect on short-term memory. Furthermore, fear induced anxiety was reduced in comparison to WT mice, suggesting that PTSD-like symptoms are also being ameliorated. Intriguingly, we found that aversive memories seem to be more strongly affected in younger mice. Finally, the analysis of CPEB3 amyloid presence in hippocampal extracted samples showed a correlative decrease in murine CPEB3 oligomerization in the TgQBP1 mice. Taking together, these results strongly suggest that the amyloidogenic blockage of CPEB3 by QBP1 peptide is a potential drug for the prevention and treatment of PTSD.

neuroscience↗

bioRxiv2024

Gut Microbiota Regulates Exercise-induced Hormetic Modulation of Cognitive Function

Lifestyle factors, particularly physical exercise, significantly influence brain structure and cognitive function through a hormetic effect dependent on exercise intensity and duration. The underlying mechanisms of this profile remain largely unexplored. Recently, the gut microbiota, has emerged a potent modulator of lifestyle-induced changes on brain and behavior. Here, we demonstrate that a 40-minute protocol of moderate exercise enhances cognitive abilities related to object recognition and memory, and increases hippocampal neurogenesis in adult mice compared to sedentary controls, but these cognitive and neurogenic benefits vanish when the exercise intensity or duration is increased. Furthermore, we identified significant alpha- and beta-diversity changes and distinct bacteria composition profiles of gut microbiota associated with different exercise regimens. Specific bacterial families showed altered relative abundances depending on exercise intensity and duration, with certain families quantities significantly correlating with cognitive performance (Angelakisella, Acetatifactor, Erysipelatoclostridium, and Coriobacteriaceae UCG-002.). To parse causal mechanisms, fecal microbiota transplantation from exercised to sedentary mice replicated the cognitive and brain structural improvements observed in the donor animals. These findings suggest that the hormetic effects of physical exercise on cognitive function and neurogenesis are mediated by corresponding changes in the gut microbiota, indicating a novel mechanistic link between exercise, brain, and gut microbiota composition.

neuroscience↗

bioRxiv2024

Age-Dependent Maturation and Rejuvenation of the Neural 3D Chromatin Interactome in Enriched Environments

Aging is a multifactorial biological process resulting in physiological and cellular decline. However, our understanding of age-related changes in 3D genome organization and the effect of external interventions on this process, remains limited. Here we describe alterations in the landscape of the 3D chromatin interactome upon aging, utilizing the low input Promoter Capture Hi-C (liCHi-C) technique with hippocampal neurons. We integrated liCHi-C data with RNA-seq data to identify functional implications. Furthermore, we assessed the effect of exposure to environmental enrichment (EE). Remarkably, our results demonstrated an age- dependent modulation of promoter interactions and expression with EE, with aging-like changes induced in young mice upon EE, likely associated with early brain maturation; while age-related alterations were reverted in old mice, leading to a partial rejuvenation of aged mouse hippocampi. These findings revealed a dynamic behaviour of the neuronal 3D chromatin structure over time, which can be modulated by external interventions.

genomics↗

bioRxiv2024

The meninges host a unique compartment of regulatory T cells that bulwarks adult hippocampal neurogenesis

Our knowledge about the meningeal immune system has recently burgeoned, particularly our understanding of how innate and adaptive effector cells are mobilized to meet brain challenges. However, information on how meningeal immunocytes guard brain homeostasis in healthy individuals remains sparse. This study highlights the heterogeneous and polyfunctional regulatory-T (Treg) cell compartment in the meninges. A Treg subtype specialized in controlling Th1-cell responses and another known to control responses in B-cell follicles were substantial components of this compartment, foretelling that punctual Treg-cell ablation rapidly unleashed interferon-gamma production by meningeal lymphocytes, unlocked their access to the brain parenchyma, and altered meningeal B-cell profiles. Distally, the hippocampus assumed a reactive state, with morphological and transcriptional changes in multiple glial-cell types; within the dentate gyrus, neural stem cells showed exacerbated death and desisted from further differentiation, associated with inhibition of spatial-reference memory. Thus, meningeal Treg cells are a multifaceted bulwark to brain homeostasis at steady-state. One sentence summaryA distinct population of regulatory T cells in the murine meninges safeguards homeostasis by keeping local interferon-{gamma}-producing lymphocytes in check, thereby preventing their invasion of the parenchyma, activation of hippocampal glial cells, death of neural stem cells, and memory decay.

immunology↗

bioRxiv2020

An Anti-amyloidogenic treatment to specifically block the consolidation of traumatic events in mouse

Post-traumatic stress disorder (PTSD) is a mental health disorder triggered by the exposure to a traumatic event that manifests with anguish, intrusive memories and negative mood changes. So far, there is no efficient treatment for PTSD other than symptomatic palliative care. Based on the implication of the functional amyloid cytoplasmic polyadenylation element binding protein-3 (CPEB3) in the consolidation of memory, we propose its active amyloid state as a possible therapeutic target by blocking the consolidation of traumatic memories through polyglutamine binding peptide 1 (QBP1), an inhibitor of the amyloid oligomerization previously investigated in Drosophila. To test this idea in mammals, here we have developed a transgenic mouse that constitutively expresses QBP1 peptide. We first assessed the innocuousness of this peptide for the normal development of the animal, which also showed normal locomotor activity and anxiety. By performing a battery of standard memory paradigms, we then showed that hippocampal-dependent and aversive memories were impaired in the QBP1 mice. Furthermore, protein expression in the hippocampi of experienced mice showed that QBP1 mice do not increase their levels of amyloid oligomerization, evincing the blockade of the CPEB3 protein in its inactive state. The ability of QBP1 to block aversive memories in mice represents the proof of concept of a novel pharmacological approach for prophylaxis and therapy of acute stress and post-traumatic stress disorders.

animal behavior and cognition↗