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Atienza-Navarro, I.

Publications and source records attributed to Atienza-Navarro, I..

2 recordsLinked to original sources

Sex-Specific neurogenic and cognitive responses in a murine model of accelerated aging

Aging is associated with cognitive deterioration accompanied by a reduction in hippocampal neurogenesis. Murine models have been widely used to study aging and age-related cognitive decline, as they recapitulate many of the key features of the degenerative process. Among these, the SAMP8 strain represents a well-established model of accelerated aging, characterized by early-onset and progressive cognitive impairment, Alzheimers disease-like neuropathology, and an initial increase in hippocampal neurogenesis that ultimately depletes the neural stem cell pool. Notably, most studies using murine models of aging or neurodegeneration have focused on males or mixed-sex cohorts, leaving sex-specific differences in neurogenesis and cognitive decline largely unexplored. Recent evidence indicates that diterpenoid treatment ameliorates cognitive decline and enhances neurogenesis in 6-month-old male SAMP8 mice. However, whether females exhibit similar responses remains unknown. In this study, we characterized sex differences in hippocampal neurogenesis in 6-month-old SAMP8 mice and examined potential sex-dependent effects of diterpenoid therapy. Our findings reveal marked sex differences in neurogenic capacity and treatment responsiveness. While diterpenoid treatment enhanced hippocampal neurogenesis and cognitive performance in males, these effects were largely absent in females. Overall, female SAMP8 mice exhibited reduced baseline neurogenesis and a diminished response to therapy, underscoring the importance of considering biological sex in the design of therapeutic strategies for age-related cognitive decline.

pharmacology and toxicology↗

Rescue of neurogenesis and age-associated cognitive decline in SAMP8 mouse: role of transforming growth factor alpha

Neuropathological aging is associated with memory impairment and cognitive decline, and affects several brain areas including the neurogenic niche of the dentate gyrus of the hippocampus (DG). In the healthy brain homeostatic mechanisms regulate neurogenesis in the DG to facilitate the continuous generation of neurons from neural stem cells (NSC). Nevertheless, aging reduces the number of activated neural stem cells, and diminishes the number of newly generated neurons. Strategies that promote neurogenesis in the DG may improve cognitive performance in the elderly resulting in the development of treatments to prevent the progression of neurological disorders in the aged population. Our work is aimed to discover targeting molecules to be used in the design of pharmacological agents to prevent the neurological effects of pathological aging. We study the effect of age on hippocampal neurogenesis using the SAMP8 mouse as a model of pathological aging. Thus, we show that in six-month-old SAMP8 mice, episodic and spatial memory are impaired, concomitantly the generation of neuroblasts and neurons is reduced and the generation of astrocytes is increased in this model. The novelty of our work resides in the fact that treatment of SAMP8 mice with a TGF-alpha targeting molecule, prevents the observed defects, positively regulating neurogenesis and improving cognitive performance. This compound facilitates the release of TGF-alpha in vitro and in vivo and activates signaling pathways initiated by this growth factor. We conclude that targeting the release of TGF-alpha may be the basis of pharmacological drugs to counteract the neurological effects of pathological aging.

neuroscience↗