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Bales, K.

Publications and source records attributed to Bales, K..

3 recordsLinked to original sources

L-DOPA treatment promotes sustained neurovascular and synaptichomeostasis in the diabetic retina

While previous work has shown a sustained protective effect of levodopa (L-DOPA) on retinal function in early-stage diabetic retinopathy (DR) in humans, its underlying biology is unknown. Using noninvasive measures in diabetic mice, we found L-DOPA protects retinal neurovascular function as measured by oscillatory potential timing and flicker-evoked retinal vasodilation, as well as visual behavior, for at least two weeks past treatment end. Assessing changes in retinal gene expression, differentially expressed genes were broadly comparable between diabetic mice experiencing washout of L-DOPA versus continued L-DOPA treatment, with gene co-expression network analysis identifying distinct modules across L-DOPA-treated diabetic mice associated with synaptic function and cytoskeletal organization that correlated with functional protection. Together, these findings demonstrate that L-DOPA restores and sustains retinal neurovascular function in early DR and links this protection to transcriptional programs supporting synapse activity and structural integrity. TeaserL-DOPA restores neuronal and vascular performance in the diabetic retina, with benefits that lasted after treatment stopped.

neuroscience↗

CRISPR-mediated knockdown of oxytocin receptor in extended amygdala reduces stress-induced social avoidance and vigilance

Oxytocin receptors (OTRs) within the extended amygdala and nucleus accumbens (NAc) have been implicated in modulating social behaviors, particularly following stress. The effects of OTR could be mediated by modulating the activity of pre-synaptic axon terminals or via receptors in post-synaptic neurons or glia. Using a viral-mediated CRISPR/Cas9 gene editing system in female California mice (Peromyscus californicus), we selectively knocked down OTR in the anteromedial bed nucleus of the stria terminalis (BNST) or NAc to examine their roles modulating social approach and vigilance behaviors. Knockdown of OTR in the BNST attenuated stress-induced decreases of social approach and had less robust effects on vigilance when interacting with a target mouse behind a wire barrier. In this large arena, where mice could control their proximity to a target mouse, BNST OTR knockdown also increased investigation of a non-social stimulus (empty cage). Behavioral effects of BNST OTR knockdown were weaker in the small arena where focal mice physically interacted with target mice. Interestingly, OTR knockdown in the NAc, reduced stress-induced social vigilance without affecting social approach. These effects could mediated altered encoding of socially aversive experiences, as knockdown manipulations were performed before stress exposure. Together, these results highlight effects of local OTR on social behavior are region-specific.

neuroscience↗

Comparative lifespan and healthspan of nonhuman primate species common to biomedical research

There is a critical need to generate age- and sex-specific survival curves to characterize chronological aging consistently across nonhuman primates (NHP) used in biomedical research. Sex-specific Kaplan-Meier survival curves were computed in 12 translational aging models: baboon, bonnet macaque, chimpanzee, common marmoset, coppery titi monkey, cotton-top tamarin, cynomolgus macaque, Japanese macaque, pigtail macaque, rhesus macaque, squirrel monkey, and vervet/African green. After employing strict inclusion criteria, primary results are based on 12,269 NHP that survived to adulthood and died of natural/health-related causes. A secondary analysis was completed for 32,616 NHP that died of any cause. Results show a pattern of reduced male survival among catarrhines (African and Asian primates), especially macaques, but not platyrrhines (Central and South American primates). For many species, median lifespans were lower than previously reported. An important consideration is that these analyses may offer a better reflection of healthspan than lifespan since research NHP are typically euthanized for humane welfare reasons before their natural end of life. This resource represents the most comprehensive characterization of sex-specific lifespan and age-at-death distributions for 12 biomedically relevant species, to date. These results clarify relationships among NHP ages and provide a valuable resource for the aging research community, improving human-NHP age equivalencies, informing investigators of expected survival rates, providing a metric for comparisons in future studies, and contributing to understanding of factors driving lifespan differences within and among species.

physiology↗