Calcium‐Dependent Signaling in Astrocytes: Downstream Mechanisms and Implications for Cognition

Journal of Neurochemistry, Год журнала: 2025, Номер 169(2)

Опубликована: Фев. 1, 2025

Astrocytes are glial cells recognized for their diverse roles in regulating brain circuit structure and function. They can sense adapt to changes the microenvironment due unique structural biochemical properties. A key aspect of astrocytic function involves calcium (Ca2+)-dependent signaling, which serves as a fundamental mechanism interactions with neurons other brain. However, while significant progress has been made understanding spatio-temporal properties Ca2+ signals, downstream molecular pathways exact mechanisms through astrocytes decode these signals regulate homeostatic physiological processes remain poorly understood. To address this topic, we review here available literature on sources intracellular Ca2+, well its signaling pathways. We well-studied Ca2+-dependent exocytosis but draw attention additional that less understood are, most likely, highly influential many cellular functions. Finally, how is thought underlie neuron-astrocyte regions involved cognitive processing.

Язык: Английский

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Engrams across diseases: Different pathologies – unifying mechanisms?

Neurobiology of Learning and Memory, Год журнала: 2025, Номер unknown, С. 108036 - 108036

Опубликована: Фев. 1, 2025

Язык: Английский

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Diverse synaptic mechanisms underlying learning and memory consolidation

Current Opinion in Neurobiology, Год журнала: 2025, Номер 92, С. 102996 - 102996

Опубликована: Март 5, 2025

Memory consolidation is defined as the process by which labile short-term memories are stabilized and transformed into persistent long-term memories. This relies heavily on synaptic plasticity, particularly potentiation depression (LTP LTD, respectively), have been extensively investigated in previous studies. The advent of optical tools that allow observation manipulation LTP LTD vivo has advanced our understanding their roles learning memory consolidation. In addition to recent research indicated presence a more rapid plasticity mechanism, termed behavioral timescale (BTSP), crucial for encoding space context. Sharp-wave ripples sleep also play indispensable consolidation, with some studies alternately linking them LTD. At systems level, sharp-wave contribute transmission information broader brain areas, well modification strength cortical areas storage memory. Furthermore, findings highlighted role non-neuronal cells learning, they modulate various ways.

Язык: Английский

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Unraveling the transcriptome of pyramidal neurons from human hippocampus under aging, amnestic mild-cognitive impairment, and sex-interactions

Exploration of Medicine, Год журнала: 2025, Номер unknown

Опубликована: Апрель 1, 2025

Aim: Amnestic mild cognitive impairment (aMCI) is a transitional stage toward Alzheimer’s disease (AD). For late-onset AD (95% of cases), aging the main risk factor. Systematizing transcriptome hippocampal neurons under native conditions this essential, as information scarce and hippocampus highly vulnerable cerebral region. Methods: Public microarray data corresponding to homogenates human Healthy-Younger, Healthy-Elder, Elder-with-MCI individuals were re-analyzed herein. Through an optimized computational pipeline, those genes having splice forms that belong neuronal type identified. The differential arising from each group then characterized by contrasting ontologies (functions, cellular components, pathways). Additionally, re-arranged factorially determine first- second-order sex interactions. Results: Around 76% relevant changes actually occurred during healthy-aging process, being further balanced or not MCI. “Cognition”, “behavior”, “glutamatergic synaptic transmission”, “lipid rafts”, “catecholamines” decreased across three groups analyzed, whereas “associative/visual learning”, “gliogenesis”, “neuro-inflammation”, “corticosteroids”, “p75NTR”, “ER-stress” “autophagy” peaked in Elders. On contrary, “Learning/memory”, “GAP junctions”, “GABAergic “GNDF” showed minimum “transcriptional regulators” (MeCP2, NPAS4, DREAM), “BNDF/NGFR”, “Ca2+ transport”, “CRHR1” “CXCL12” minimal From Elder MCI, “MAPKs”, “MEF2C”, “RGS7”, “CCKBR1”, “ErbB4”, “ERK5”, “Ca2+-Na+-K+ channels” (RYR2, SCNA1/A8, KCNQ2/Q3, KCNN3, KCNIP2) appeared downregulated. “Long-term depression” (LTD) increased sharply Most findings detected contrasted against 250 reports. Conclusions: multiple alterations basic mechanisms—mainly CA3 dendrites mossy fibers could be compatible with hyper-excitability, diminished transmission, theta/gamma/SWR rhythms. Many functionalities conditioned sex-interactions. Particularly, women “pure” sex-effects interactions “cross-over” effects. Due its consequences on higher-order functions, all these predictions should confirmed experimentally.

Язык: Английский

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The molecular and cellular basis of memory engrams: Mechanisms of synaptic and systems consolidation

Neurobiology of Learning and Memory, Год журнала: 2025, Номер unknown, С. 108057 - 108057

Опубликована: Апрель 1, 2025

Язык: Английский

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