Biology subjects

Aguilera, M.

Publications and source records attributed to Aguilera, M..

10 recordsLinked to original sources

bioRxiv2026

Claustral pathway coordinates distributed cortical dynamics with hippocampal output during sleep to promote memory consolidation

The claustrum is a broadly connected subcortical structure proposed to coordinate distributed cortical activity. Claustral neurons are recruited during synchronized brain states and contribute to sleep-dependent memory consolidation, primarily through effects on cortical dynamics. Yet the claustrum also innervates the subicular complex, a major hippocampal output node, raising the possibility that it may regulate both cortical state and hippocampo-cortical dialogue during sleep. Here, we identify a projection-defined population of claustral neurons targeting the subicular complex, CLAsc, that is preferentially recruited during slow-wave sleep and tracks cortical and subicular sleep dynamics. Optogenetic activation of CLAsc neurons during post-learning sleep enhanced spatial memory consolidation without detectable changes in ripple occurrence or slow-oscillation-spindle coupling. Instead, CLAsc activation imposed a stereotyped cortical-subicular motif: a brief gamma-rich Up state followed by a coordinated Down state across prefrontal, retrosplenial and subicular regions. Within this gamma-rich Up state, interareal coherence increased, gamma bursts became synchronized, and lagged directed interactions were transiently reorganized, including an enhanced prefrontal-to-subicular component. Together, these findings identify the claustrum as a state-dependent coordinator that transforms ongoing cortical and hippocampal-output activity into coordinated network transitions during sleep, providing a circuit mechanism through which distributed brain states may support memory consolidation.

neuroscience↗

bioRxiv2025

Molecular mechanisms of 10-Butyl Ether Minocycline (BEM), a novel non-antibiotic tetracycline, as a potential treatment for inflammatory and neuroimmune-related disorders.

The pleiotropy of minocycline (MINO), including anti-inflammatory, antioxidant, anti-migratory, anti-MMP, and neuroprotective effects, has been extensively reported. A novel non-antibiotic minocycline derivative, 10-butyl ether minocycline (BEM), was synthesized to retain the pleiotropy of minocycline while minimizing side effects such as antibiotic resistance and gut dysbiosis. Previously, we showed that BEM reduced alcohol consumption in dependent murine and porcine models of Alcohol Use Disorder (AUD). In this study, we investigated the molecular mechanisms of BEM to determine its potential as a therapeutic agent for neuroimmune and inflammatory conditions such as AUD. Here, we report that BEM showed a nearly complete loss of antimicrobial activity against E. coli, S. typhi, and C. albicans. BEM showed a dose-dependent reduction in cell viability as measured by the MTT assay, similarly to MINO. BEM also suppressed LPS-induced microglial activation as shown by reduced Iba1 expression in immunohistochemistry and western blot analyses. Inhibition of MMP-9 by BEM (IC50 = 42.2 {micro}M) was improved compared to MINO (IC50 = 60.3 {micro}M) while MMP-8 inhibition was moderate (IC50: BEM = 69.4 {micro}M; MINO = 45.4 {micro}M). BEM was found to be effective in inhibiting VEGF-induced endothelial cell migration and L-glutamine-induced ROS levels. Limited inhibition of 15-LOX activity was observed (IC50: BEM = 92.6 {micro}M; MINO = 65.6 {micro}M). BEM was not toxic to mitochondria, even at high concentrations (200 {micro}M). By eliminating antimicrobial properties while preserving therapeutic pleiotropy, BEM presents an advancement in the development of a promising candidate with multimodal mechanisms to treat neuroimmune-inflammatory pathologies. ImpactOur current approach to correlate non-antibacterial actions of BEM to MINOs established mechanistic effects will enable the informed use of BEM for several medical indications including for inflammation and neuroimmune conditions. The focus on BEMs multimodal actions and long-term safety during drug discovery represents a paradigm shift toward complex therapeutic drug development and repositioning, improving upon traditional singular high-affinity target-based approaches. Such new drug discovery attempts could potentially enhance treatment relevance in complex disorders with multiple targets and theoretically guide the creation of second-generation analogs. Significance statementWe report mechanisms of action for BEM, a minocycline analog under evaluation for the treatment of Alcohol Use Disorder, which may also show efficacy for other complex disease processes that involve inflammatory or neuroimmune components. We show that BEM had a nearly complete loss of antimicrobial action, yet retained the pleiotropy of MINO, likely making it a better multimodal therapeutic for long-term treatment of complex diseases with neuroimmune-related components. Visual abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=120 SRC="FIGDIR/small/661183v3_ufig1.gif" ALT="Figure 1"> View larger version (54K): org.highwire.dtl.DTLVardef@1ade11corg.highwire.dtl.DTLVardef@961d1borg.highwire.dtl.DTLVardef@15101f8org.highwire.dtl.DTLVardef@158810e_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

bioRxiv2024

40 Hz light stimulation restores early brain dynamics alterations and associative memory in Alzheimer's disease model mice

Visual gamma entrainment using sensory stimuli (vGENUS) is a promising non-invasive therapeutic approach for Alzheimers disease (AD), showing efficacy in improving memory function. However, its mechanisms of action remain poorly understood. Using young AppNL-F/MAPT double knock-in (dKI) mice, a model of early AD, we examined brain dynamics alterations before amyloid plaque onset. High-density EEG recordings and novel metrics from fields outside neuroscience were used to assess brain dynamics fluidity--a measure of the brains ability to transition between activity states. We revealed that dKI mice exhibit early, awake state-specific reductions in brain dynamics fluidity associated with cognitive deficits in complex memory tasks. Daily vGENUS sessions over two weeks restored brain dynamics fluidity and rescued memory deficits in dKI mice. Importantly, these effects built up during the stimulation protocol and persisted after stimulation ended, suggesting long-term modulation of brain function. Based on these results, we propose a "brain dynamics repair" mechanism for vGENUS that goes beyond current amyloid-centric hypotheses. This dual insight - that brain dynamics are both a target for repair and a potential diagnostic tool - provides new perspectives on early Alzheimers disease pathophysiology. Significance StatementGamma ENtrainment Using Sensory stimuli (GENUS), involving 40 Hz rhythmic sensory stimulation, shows promise in improving memory function in Alzheimers disease (AD). We hypothesized that brain dynamics changes could be detected before plaque onset and modulated by vGENUS. Applying techniques from climate science to EEG recordings in young AD model mice, we found reduced brain dynamics fluidity associated with early cognitive deficits. Two weeks of vGENUS restored brain dynamics and improved memory, with effects persisting post-treatment. These findings challenge the amyloid-centric view of AD, introduce a potential early biomarker, and suggest vGENUS acts by "repairing" brain dynamics. Our approach offers new perspectives on early diagnosis and non-invasive interventions for AD and other neurological disorders with disrupted brain dynamics.

neuroscience↗

bioRxiv2023

The Horizontal Ladder Test (HLT) protocol: A novel, optimized, and reliable means of assessing motor coordination in Sus scrofa domesticus

Pigs can be an important model for preclinical biological research, including neurological diseases such as Alcohol Use Disorder. Such research often involves longitudinal assessment of changes in motor coordination as the disease or disorder progresses. Current motor coordination tests in pigs are derived from behavioral assessments in rodents and lack critical aspects of face and construct validity. While such tests may permit for the comparison of experimental results to rodents, a lack of validation studies of such tests in the pig itself may preclude the drawing of meaningful conclusions. Here, we present a novel, optimized, and reliable horizontal ladder test (HLT) test protocol for evaluating motor coordination in pigs and an initial validation of its construct validity using voluntary alcohol consumption as an experimental manipulation. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=157 SRC="FIGDIR/small/571517v2_ufig1.gif" ALT="Figure 1"> View larger version (101K): org.highwire.dtl.DTLVardef@167924eorg.highwire.dtl.DTLVardef@b674f2org.highwire.dtl.DTLVardef@b7c369org.highwire.dtl.DTLVardef@7e5a42_HPS_FORMAT_FIGEXP M_FIG C_FIG

animal behavior and cognition↗

bioRxiv2022

The efficacy of chemotherapy is limited by intratumoural senescent cells that persist through the upregulation of PD-L2

Anti-cancer therapies often result in a subset of surviving cancer cells that undergo therapy-induced senescence (TIS). Senescent cancer cells strongly modify the intratumoural microenvironment favoring immunosuppression and, thereby, tumour growth. An emerging strategy to optimise current therapies is to combine them with treatments that eliminate senescent cells. To this end, we undertook an unbiased proteomics approach to identify surface markers contributing to senescent cells immune evasion. Through this approach, we discovered that the immune checkpoint inhibitor PD-L2, but not PD-L1, is upregulated across multiple senescent human and murine cells. Importantly, blockade of PD-L2 strongly synergises with genotoxic chemotherapy, causing remission of solid tumours in mice. We show that PD-L2 inhibition prevents the persistence of chemotherapy-induced senescent cells, which exert cell-extrinsic immunomodulatory actions. In particular, upon chemotherapy, tumours deficient in PD-L2 fail to produce cytokines of the CXCL family, do not recruit myeloid-derived suppressor cells (MDSCs) and are eliminated in a CD8 T cell-dependent manner. We conclude that blockade of PD-L2 improves chemotherapy efficacy by reducing the intratumoural burden of senescent cells and their associated recruitment of immunosuppressive cells. These findings provide a novel strategy to exploit vulnerabilities arising in tumour cells as a result of therapy-induced damage and cellular senescence.

cancer biology↗

bioRxiv2022

Iron accumulation drives fibrosis, senescence, and the senescence-associated secretory phenotype

Fibrogenesis is part of a normal protective response to tissue injury that can become irreversible and progressive, leading to fatal diseases. Senescent cells are a main driver of fibrotic diseases through their secretome, known as senescence-associated secretory phenotype (SASP). However, the mechanisms involved in the conversion of damaged cells into senescent cells remain incompletely understood. Here, we report that multiple types of fibrotic diseases in mice and humans are characterized by the accumulation of iron. We show that vascular and hemolytic injuries, through the release of iron, are efficient in triggering senescence and fibrosis. Interestingly, the accumulation of iron is an intrinsic property of senescent cells that does not require an abnormal surge in extracellular iron. Upon damage, cells initiate an iron accumulation response with abundant ferritin-bound iron within lysosomes and high levels of labile iron, the latter being a main driver of senescence-associated ROS and SASP. Finally, we demonstrate that detection of iron by magnetic resonance imaging (MRI) is a powerful non-invasive method to assess fibrotic burden in the kidneys of mice and patients with renal fibrosis. Our findings establish a central role for iron accumulation in senescence and fibrogenesis.

physiology↗

bioRxiv2022

Deciphering the roadmap of in vivo reprogramming towards pluripotency

Differentiated cells can be converted to pluripotent stem cells (iPSCs) upon ectopic expression of transcription factors OCT4, SOX2, KLF4 and MYC (OSKM) in a process known as reprogramming. Great efforts have been made to dissect intermediate states of in vitro reprogramming and how they are affected by culture conditions, while the roadmap of in vivo reprogramming remains unexplored. Here, we use single cell RNA sequencing to capture cells undergoing reprogramming in the adult pancreas. We identify markers along the trajectory from acinar identity to pluripotency, which allow in situ visualization of the intermediate states of reprogramming. Importantly, different tissues expressing OSKM, such as pancreas, stomach and colon, share markers of intermediate reprogramming, suggesting a conserved in vivo reprogramming path. Our in vivo roadmap defines landmarks along in vivo reprogramming that could be useful for applications in tissue regeneration and cellular rejuvenation based on intermediate reprogramming states.

developmental biology↗

bioRxiv2022

Multi-omic rejuvenation of naturally aged tissues by a single cycle of transient reprogramming

The expression of the pluripotency factors OCT4, SOX2, KLF4 and MYC (OSKM) can convert somatic differentiated cells into pluripotent stem cells in a process known as reprogramming. Notably, cycles of brief OSKM expression do not change cell identity but can reverse markers of aging in cells and extend longevity in progeroid mice. However, little is known about the mechanisms involved. Here, we have studied changes in the DNA methylome, transcriptome and metabolome in naturally aged mice subject to a single period of transient OSKM expression. We found that this is sufficient to reverse DNA methylation changes that occur upon aging in the pancreas, liver, spleen and blood. Similarly, we observed reversion of transcriptional changes, especially regarding biological processes known to change during aging. Finally, some serum metabolites altered with aging were also restored to young levels upon transient reprogramming. These observations indicate that a single period of OSKM expression can drive epigenetic, transcriptomic and metabolomic changes towards a younger configuration in multiple tissues and in the serum.

cell biology↗

bioRxiv2021

Lack of p62 impairs glycogen aggregation and exacerbates pathology in a mouse model of myoclonic epilepsy of Lafora

BackgroundLafora disease (LD) is a fatal childhood-onset dementia characterized by the extensive accumulation of glycogen aggregates--the so-called Lafora Bodies (LBs)--in several organs. The accumulation of LBs in the brain underlies the neurological phenotype of the disease. LBs are composed of abnormal glycogen and various associated proteins, including p62, an autophagy adaptor that participates in the aggregation and clearance of misfolded proteins. MethodsTo study the role of p62 in the formation of LBs and its participation in the pathology of LD, we generated a mouse model of the disease (malinKO) lacking p62. ResultsDeletion of p62 prevented LB accumulation in skeletal muscle and cardiac tissue. In the brain, the absence of p62 altered LB morphology and increased susceptibility to epilepsy. ConclusionsThese results demonstrate that p62 participates in the formation of LBs and suggest that the sequestration of abnormal glycogen into LBs is a protective mechanism through which to reduce the deleterious consequences of its accumulation in the brain.

neuroscience↗

bioRxiv2020

A plausible mechanism for Drosophila larva intermittent behavior.

The behavior of many living organisms is not continuous. Rather, activity emerges in bouts that are separated by epochs of rest, a phenomenon known as intermittent behavior. Although intermittency is ubiquitous across phyla, empirical studies are scarce and the underlying neural mechanisms remain unknown. Here we present the first empirical evidence of intermittency during Drosophila larva free exploration. We report power-law distributed rest-bout and log-normal distributed activity-bout durations. We show that a stochastic network model can transition between power-law and non-power-law distributed states and we suggest a plausible neural mechanism for the alternating rest and activity in the larva. Finally, we discuss possible implementations in behavioral simulations extending spatial Levy-walk or coupled-oscillator models with temporal intermittency.

animal behavior and cognition↗