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Tinsley, C. E.

Publications and source records attributed to Tinsley, C. E..

3 recordsLinked to original sources

Developmental time course of social touch, parvalbumin interneurons, perineuronal nets and Mef2c expression reveals a sensitive period of somatosensory cortex development in prairie voles

Social touch facilitates our attachment to others, especially early in life, which may be linked to the maturation of parvalbumin interneurons (PVI) in the somatosensory cortex (S1). These neurons respond to social touch, mature in a sensory experience-dependent manner, and influence both somatosensory processing and social behavior in models of Autism Spectrum Disorder. Prairie voles (Microtus ochrogaster) are an ideal rodent model for studying these concepts since they engage in a species-typical social touch called "huddling". This study first showed that over development from juvenile to adult, same-sex siblings huddled less and explored more. Next, we tracked two markers of plasticity indicative of PVI maturation, extracellular perineuronal nets (PNNs) and nuclear transcription factor Myocyte enhancing factor 2C (Mef2c) - across seven developmental timepoints. We found that, while PV expression in S1 was stable by P21, PNNs and Mef2c continued to shift afterwards, indicating a protracted development. Four unique clusters of PVIs converge during development between P14-P21, suggesting a sensitive period of PVI development. Finally, to determine environmental factors affecting these processes, environmental enrichment between P21-P28 led to accelerated PVI maturation. This developmental mapping provides a particularly salient model to investigate the molecular underpinnings of cortical and social development.

neuroscience↗

Centella asiatica improves sleep quality and quantity in aged mice

Age-related sleep disruption is common in older adults. Not only does the total amount of time spent in sleep decline, but the number of arousals during sleep increases with age. As sleep is important for both memory consolidation and to prevent neurodegenerative pathology, this decline in sleep and/or sleep consolidation may underlie age-related cognitive decline and dementias. Furthermore, treatment of sleep disruption can improve quality of life. However, few interventions have successfully reversed age-related sleep decline. Extracts from the plant Centella asiatica have demonstrated neuroprotective effects in human, rodent, and fly models of aging and neurodegenerative diseases, and is a promising intervention for dementias, yet little is known about how these extracts affect sleep patterns. Here, we administered Centella asiatica water extract (CAW) dosed or control chow to male and female C57BL6/J mice aged 18 months. Effects on sleep composition were determined using electrodes that recorded EEG and EMG signals. We found that CAW dosed chow (1000 mg/kg/day) increased REM sleep time in aged male mice and decreased the number of arousals during sleep observed in aged females, compared to age- and sex-matched controls. We conclude that CAW administered in food has a moderate, sex-dependent effect on sleep quantity and quality. Statement of SignificanceSleep declines with age and may underline age-related cognitive changes. However, few interventions have successfully reversed age-related sleep and cognitive decline. This study found that botanical extract from the plant Centella asiatica increased total REM sleep time in aged male mice, and decreased sleep fragmentation in aged female mice, compared to age- and sex-matched controls. Whether these moderate, sex-dependent effect sizes on sleep in aged mice are impactful enough to affect cognition, quality of life, and/or neurodegenerative pathology could be explored in future studies.

neuroscience↗

SEX-SPECIFIC IMPACTS OF EARLY LIFE SLEEP DISRUPTION: ETHANOL SEEKING, SOCIAL INTERACTION, AND ANXIETY ARE DIFFERENTIALLY ALTERED IN ADOLESCENT PRAIRIE VOLES

Early life sleep is important for neuronal development and maturation. Using the highly social prairie vole rodent model, we have previously reported that early-life sleep disruption (ELSD) during the pre-weaning period postnatal day (P)14 to 21 results in adult interference with social bonding and increases ethanol consumption following a stressor. Furthermore, we have reported increased parvalbumin expression and reduced glutamatergic neurotransmission in cortical regions in adult prairie voles that experienced this paradigm. To understand the impact of ELSD on the lifespan, examination of an earlier time in life is necessary. Thus, the aim of the present study was to examine the behavioral outcomes of ELSD on adolescent prairie voles. Here we hypothesized that anxiety and reward related behaviors, as measured by light/dark box, 2-bottle choice and social interactions, would be negatively impacted by ELSD in adolescent male and female prairie voles. Male ELSD voles were no different from control voles in measures of anxiety and ethanol preference or consumption, but affiliative social interactions were significantly reduced. ELSD differentially impacted female prairie voles, with increased anxiety-like behavior and reductions in ethanol consumption compared to Controls, but no impact on ethanol preference or social interactions. Together, these results suggest both male and female prairie voles experience differential changes to reward seeking behaviors, but only female prairie voles showed increases in anxiety-like behavior. These results further suggest that early-life sleep is critically important for neurotypical behaviors in adolescence, a time where reward-seeking and risky behaviors are adaptive for learning and promoting survival.

animal behavior and cognition↗