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Brown, K. A.

Publications and source records attributed to Brown, K. A..

2 recordsLinked to original sources

Deliberation and enaction during adaptive economic choice

Economic decisions can adapt to contexts. Choices can be quick and impulsive or slow and more deliberative, depending on the temporal context. Choices can also depend on how we enact the choice, in an action context. Where we decide to go for dinner may change if we can take a taxi or need to walk.\n\nWe hypothesized that frontal action circuits could contribute to adapting economic choices to context because of their privileged position over actions as endpoints of decisions.\n\nTo test this, we performed an unbiased survey of neuronal population activity across motor, premotor and prefrontal cortices as animals expressed context-dependent economic preferences. Activity in distributed action circuits tracked the animals evolving preferences in real-time and integrated them with a signal for their enaction. We propose that frontal action circuits form a neural substrate that supports an adaptive control over economic choice by flexibly translating real-time preferences into actions.

neuroscience

No effect of administration of unacylated ghrelin on subcutaneous PC3 xenograft growth in a Rag1-/- mouse model of metabolic dysfunction

Ghrelin is a peptide hormone which, when acylated, regulates appetite, energy balance and a range of other biological processes. Ghrelin predominately circulates in its unacylated form (unacylated ghrelin; UAG). UAG has a number of functions independent of acylated ghrelin, including modulation of metabolic parameters and cancer progression. UAG has also been postulated to antagonise some of the metabolic effects of acyl-ghrelin, including its effects on glucose and insulin regulation. In this study, Rag1-/- mice with high-fat diet-induced obesity and hyperinsulinaemia were subcutaneously implanted with PC3 prostate cancer xenografts to investigate the effect of UAG treatment on metabolic parameters and xenograft growth. Daily intraperitoneal injection of 100 g/kg UAG had no effect on xenograft tumour growth in mice fed normal rodent chow or 23% high-fat diet. UAG significantly improved glucose tolerance in host Rag1-/- mice on a high-fat diet, but did not significantly improve other metabolic parameters. We hypothesise that UAG is not likely to be an effective treatment for prostate cancer, with or without associated metabolic syndrome.\n\nConflict of interestThe authors declare no conflict of interest.

cancer biology