Parkinson’s disease (PD) is characterized by oxidative stress, mitochondrial dysfunction, and dopaminergic neuron loss, for which effective treatments remain unavailable. Here, we report CL0179, a fungal-derived decahydrofluorene alkaloid with antioxidant-associated neuroprotective properties, and evaluate its effects across cellular and animal PD models. CL0179 exhibited a favorable safety profile and protected SHSY5Y against 6-hydroxydopamine- (6-OHDA), rotenone-, and 1-Methyl-4-phenylpyridinium-iodide (MPP+)-induced neurotoxicity by preserving mitochondrial membrane potential and network integrity. Transcriptomic analyses revealed selective restoration of gene-expression programs associated with oxidative phosphorylation, mitochondrial bioenergetics, and stress adaptation disrupted by MPP+. CL0179 also enhanced SIRT1 activity under MPP+ stress, whereas pharmacological SIRT1 inhibition partially attenuated protection of mitochondrial membrane potential and cell viability. In LRRK2-G2019S astrocytes, CL0179 reduced ROS and α-synuclein accumulation and restored mitochondrial organization, while in human dopaminergic neurons, it attenuated toxin-induced mitochondrial depolarization and preserved neuronal architecture. To overcome the low production of CL0179, we generated the structurally related analogue CL0670. Both compounds crossed the blood–brain barrier and protected mouse primary cortical neurons, while CL0670 improved motor deficits in a 6-OHDA mouse model. Collectively, these compounds promote mitochondrial resilience and stress-adaptive neuroprotection, supporting their potential for PD and related neurodegenerative disorders.

Abstract Astrocytes are glycolytic cells that convert a substantial fraction of glucose-derived pyruvate into lactate, a metabolite implicated in supporting neuronal energy demand and modulating excitability, plasticity and memory. This view has placed astrocytic lactate production and export at the centre of astrocyte-neuron metabolic coupling, but whether mitochondrial pyruvate utilization in astrocytes is dispensable in vivo or fulfils an essential function in the intact brain remains unknown. Here we show that adult astrocyte-specific deletion of Mpc2 , encoding an obligatory mitochondrial pyruvate carrier subunit, causes motor deficits, neuronal hyperexcitability and seizure-associated lethality. Metabolic profiling revealed pyruvate diversion toward alanine as an unsuccessful compensatory bypass, together with impaired tricarboxylic acid-cycle metabolism and an imbalance in neurotransmitter-related pools, including glutamate, glutamine and γ-aminobutyric acid. Thus, astrocytic mitochondrial pyruvate import is not primarily required for bioenergetic purposes but acts as a non-redundant anaplerotic gate that maintains neurotransmitter homeostasis, excitation-inhibition balance and seizure resistance in vivo .

La enfermedad de Alzheimer es un trastorno neurodegenerativo progresivo, caracterizado por la disfunción cognitiva, cuya prevalencia aumenta diariamente. Sus mecanismos fisiopatológicos descritos incluyen la acumulación de beta-amiloide y el estrés oxidativo. En este trabajo estudiamos la relación de dichos elementos con la proteína Bmal1, elemento del reloj circadiano central que puede alterar el desarrollo de enfermedades neurodegenerativas. Asimismo, se probaron compuestos alcaloides pirrocidínicos con actividad antioxidante y posible potencial neuroprotector de la empresa Instituto Biomar S.A. En cultivos neuronales tratados con beta-amiloide se estudió la variación de Bmal1 en medios con y sin antioxidantes mediante Western-Blot, observándose que en medio con antioxidantes se mantuvieron sus niveles. En estos cultivos, el tratamiento con los compuestos experimentales CL0179 y CL0670 logró mantener los niveles de Bmal1. Además, se cuantificó la apoptosis mediante caspasa-3, evidenciando su disminución en los cultivos tratados. Estos resultados esclarecen la relación beta-amiloide, Bmal1 y estrés oxidativo. Como indica bibliografía anterior, el beta-amiloide disminuye los niveles de Bmal1 en cultivos neuronales y el estrés oxidativo puede ser determinante en la muerte neuronal influenciada por acumulación de beta-amiloide. Los compuestos testados muestran actividad neuroprotectora, posiblemente mediada por el mantenimiento de Bmal1, abriendo una vía para el desarrollo de nuevos tratamientos contra patologías neurodegenerativas.

Astrocytic glycolysis is tightly coupled to neurotransmission and thought to be essential for neurological health. However, the metabolic adaptations that enable astrocytes to maintain a durable glycolytic profile without compromising viability are elusive. Here, using in vivo approaches including cell-specific gene expression disruption, metabolic flux analyses and behavioral tests in mice, we addressed this issue. We found that Pfkfb3 (6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3) is instrumental in maintaining the astrocytic glycolytic phenotype. Importantly, astrocytic glycolysis sustained by Pfkfb3 is required for normal cognitive performance. Mechanistically, ATP generated through glycolysis is consumed by mitochondria, via the reverse mode of ATP synthase, to conserve the proton gradient across the inner mitochondrial membrane. This enables mitochondria to attenuate pyruvate decarboxylation, tricarboxylic acid cycle and electron transport chain activity, thereby preserving pyruvate for conversion into lactate and delivery to neurons. These findings reveal that astrocytes sacrifice mitochondrial bioenergetic efficiency as a previously underappreciated strategy to support cognition. ### Competing Interest Statement The authors have declared no competing interest.

Neurons are exceptionally energy-demanding cells but have limited energy storage, relying on a constant supply of fuel and oxygen. Although glucose is the brain's main energy source, neurons reduce glycolysis under normal conditions. This surprising strategy helps to protect mitochondria by preserving nicotinamide-adenine dinucleotide (NAD+), a vital cofactor consumed by glycolysis. NAD+ is needed for sirtuin-driven mitophagy, a process that removes damaged mitochondria. By saving NAD+, neurons can maintain healthy, energy-efficient mitochondria. These mitochondria then use alternative fuels such as lactate and ketone bodies from astrocytes. Here, we discuss the way in which this balance between reduced glycolysis and active mitophagy supports brain function and overall metabolic health, highlighting a sophisticated system that prioritizes mitochondrial quality for long-term cognitive performance and systemic homeostasis.

Retinal detachment (RD) separates the retina from the retinal epithelium, causing photoreceptor apoptosis and irreversible vision loss. Even with successful surgical reattachment, complete visual recovery is not guaranteed. The TP53 Arg72Pro polymorphism, implicated in apoptosis, has emerged as a potential predictor of RD outcomes. We investigated the impact of the Arg72Pro polymorphism on retinal neurodegeneration and functional recovery in patients. The underlying mechanisms were analyzed in a humanized TP53 Arg72Pro RD mouse model. In a cohort of 180 patients, carriers of the Pro allele exhibited decreased apoptotic gene expression and improved visual recovery. Complementary findings in mice revealed that the Pro variant preserved photoreceptor integrity and reduced apoptosis rates following RD. Our findings highlight the potential of this TP53 polymorphism as a biomarker for RD outcomes and a tool for tailoring therapies. This study underscores the importance of integrating genetic profiling into personalized medicine approaches to improve recovery of RD patients' visual outcomes.

The energy cost of neuronal activity is mainly sustained by glucose 1,2 . However, in an apparent paradox, neurons only weakly metabolize glucose through glycolysis 3,4,5,6 , a circumstance that can be accounted for by the constant degradation of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (Pfkfb3) 3,7,8 , a key glycolysis-promoting enzyme. To evaluate the in vivo physiological significance of this hypo-glycolytic metabolism, here we genetically engineered mice with their neurons transformed into active glycolytic cells through Pfkfb3 expression. In vivo molecular, biochemical, and metabolic flux analyses of these neurons revealed an accumulation of anomalous mitochondria, complex I disassembly, bioenergetic deficiency and mitochondrial redox stress. Notably, glycolysis-mediated NAD + reduction impaired sirtuin-dependent autophagy. Furthermore, these mice displayed cognitive decline and a metabolic syndrome that was mimicked by confining Pfkfb3 expression to hypothalamic neurons. Neuron-specific genetic ablation of mitochondrial redox stress corrected these alterations. Thus, the weak glycolytic nature of neurons is required to sustain higher-order organismal functions.

Ca2+ is an ion of great importance for a plethora of cellular processes and its intracellular concentrations are tightly controlled by diverse organelles and transporters. In the mitochondria

Background and PurposeThe prognostic significance of postcontrast enhancement of intracranial atheromatous plaque is uncertain. Prospective, long-term follow-up studies in Caucasians, using a multicenter design, are lacking. We aimed to evaluate whether this radiological sign predicts long-term new stroke in symptomatic and asymptomatic intracranial atherosclerotic disease (ICAD) patients. MethodsThis was a prospective, observational, longitudinal, multicenter study. We included a symptomatic and an asymptomatic cohort of ICAD patients that underwent 3T MRI including high-resolution sequences focused on the atheromatous plaque. We evaluated grade of stenosis, plaque characteristics, and gadolinium enhancement ratio (postcontrast plaque signal/postcontrast corpus callosum signal). The occurrence of new events was evaluated at 3, 6, 9, and 12 months and annually thereafter. The association between plaque characteristics and new stroke was studied using Cox multiple regression survival analysis and Kaplan-Meier curves. ResultsForty-eight symptomatic and 13 asymptomatic patients were included. During 56.3 +/- 16.9 months, 11 patients (18%) suffered a new event (seven ischemic, two hemorrhagic, and two transient ischemic attacks). A receiver operating characteristic curve identified an enhancement ratio of >1.77 to predict a new event. In a multivariable Cox regression, postcontrast enhancement ratio >1.77 (hazard ratio [HR]= 3.632; 95% confidence interval [CI], 1.082-12.101) and cerebral microbleeds (HR = 5.244; 95% CI, 1.476-18.629) were independent predictors of future strokes. Patients with a plaque enhancement ratio >1.77 had a lower survival free of events (p < .05). ConclusionsHigh intracranial postcontrast enhancement is a long-term predictor of new stroke in ICAD patients. Further studies are needed to elucidate whether postcontrast enhancement reflects inflammatory activity of intracranial atheromatous plaque.

Having direct access to brain vasculature, astrocytes can take up available blood nutrients and metabolize them to fulfil their own energy needs and deliver metabolic intermediates to local synapses 1 , 2 . These glial cells should be, therefore, metabolically adaptable to swap different substrates. However, in vitro and in vivo studies consistently show that astrocytes are primarily glycolytic 3 – 7 , suggesting glucose is their main metabolic precursor. Notably, transcriptomic data 8 , 9 and in vitro 10 studies reveal that mouse astrocytes are capable of mitochondrially oxidizing fatty acids and that they can detoxify excess neuronal-derived fatty acids in disease models 11 , 12 . Still, the factual metabolic advantage of fatty acid use by astrocytes and its physiological impact on higher-order cerebral functions remain unknown. Here, we show that knockout of carnitine-palmitoyl transferase-1A (CPT1A)—a key enzyme of mitochondrial fatty acid oxidation—in adult mouse astrocytes causes cognitive impairment. Mechanistically, decreased fatty acid oxidation rewired astrocytic pyruvate metabolism to facilitate electron flux through a super-assembled mitochondrial respiratory chain, resulting in attenuation of reactive oxygen species formation. Thus, astrocytes naturally metabolize fatty acids to preserve the mitochondrial respiratory chain in an energetically inefficient disassembled conformation that secures signalling reactive oxygen species and sustains cognitive performance.

Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by progressive cognitive decline, which is causally related to the accumulation of abnormally folded amyloid-β (Aβ) peptide and hyperphosphorylated tau protein aggregates. The dendritic spine regulator Rho protein kinase 2 (Rock2) accumulates in the brain at the earliest stages of AD and remains increased during disease progression. However, the molecular mechanism that upregulates Rock2 in AD, and its role in the disease progression, are unknown. Here, we found that oligomers of the amyloidogenic fragment 25–35 of the Aβ peptide (Aβ25-35) trigger Rock2 accumulation and activation in mouse cortical neurons in primary culture and in mouse hippocampus in vivo. Neuronal apoptotic death and memory impairment caused by Aβ25-35 administration were rescued by genetic and pharmacological inhibition of Rock2 activity. Mechanistically, Aβ25-35 elicited cyclin dependent kinase-5 (Cdk5)-mediated phosphorylation of Cdh1, a cofactor that is essential for the activity of the E3 ubiquitin ligase anaphase-promoting complex/cyclosome (APC/C) in neurons. Notably, phosphorylated Cdh1 was disassembled from the APC/C complex, causing its inactivation and subsequent Rock2 protein stabilization and activation. Moreover, Aβ25-35-induced neuronal apoptosis was prevented by expressing a phosphodefective form of Cdh1, but not by a phosphomimetic Cdh1. Finally, Cdh1 inactivation, using both genetic and pharmacological approaches, enhanced Aβ25-35-mediated neuronal death through a mechanism that was prevented by inhibition of Rock2 activity. These results indicate that the Cdk5-Cdh1 signaling pathway accounts for the increased Rock2 activity by amyloidogenic Aβ peptides and that this mechanism may contribute to neurodegeneration and memory loss in AD.

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disorder and the main cause of dementia in the elderly. The disease has a high impact on individuals and their families and represents a growing public health and socio-economic burden. Despite this, there is no effective treatment options to cure or modify the disease progression, highlighting the need to identify new therapeutic targets. Synapse dysfunction and loss are early pathological features of Alzheimer’s disease, correlate with cognitive decline and proceed with neuronal death. In the last years, the E3 ubiquitin ligase anaphase promoting complex/cyclosome (APC/C) has emerged as a key regulator of synaptic plasticity and neuronal survival. To this end, the ligase binds Cdh1, its main activator in the brain. However, inactivation of the anaphase promoting complex/cyclosome-Cdh1 complex triggers dendrite disruption, synapse loss and neurodegeneration, leading to memory and learning impairment. Interestingly, oligomerized amyloid-β (Aβ) peptide, which is involved in Alzheimer’s disease onset and progression, induces Cdh1 phosphorylation leading to anaphase promoting complex/cyclosome-Cdh1 complex disassembly and inactivation. This causes the aberrant accumulation of several anaphase promoting complex/cyclosome-Cdh1 targets in the damaged areas of Alzheimer’s disease brains, including Rock2 and Cyclin B1. Here we review the function of anaphase promoting complex/cyclosome-Cdh1 dysregulation in the pathogenesis of Alzheimer’s disease, paying particular attention in the neurotoxicity induced by its molecular targets. Understanding the role of anaphase promoting complex/cyclosome-Cdh1-targeted substrates in Alzheimer’s disease may be useful in the development of new effective disease-modifying treatments for this neurological disorder.

Intracellular Ca2+ concentrations are strictly controlled by plasma membrane transporters, the endoplasmic reticulum, and mitochondria, in which Ca2+ uptake is mediated by the mitochondrial calcium uniporter complex (MCUc), while efflux occurs mainly through the mitochondrial Na+ /Ca2+ exchanger (NCLX). RNAseq database repository searches led us to identify the Nclx transcript as highly enriched in astrocytes when compared with neurons. To assess the role of NCLX in mouse primary culture astrocytes, we inhibited its function both pharmacologically or genetically. This resulted in re-shaping of cytosolic Ca2+ signaling and a metabolic shift that increased glycolytic flux and lactate secretion in a Ca2+ -dependent manner. Interestingly, in vivo genetic deletion of NCLX in hippocampal astrocytes improved cognitive performance in behavioral tasks, whereas hippocampal neuron-specific deletion of NCLX impaired cognitive performance. These results unveil a role for NCLX as a novel modulator of astrocytic glucose metabolism, impacting on cognition.