Obesity Impairs Cognitive Function with No Effects on Anxiety-like Behaviour in ZebrafishShow others and affiliations
2023 (English)In: International Journal of Molecular Sciences, ISSN 1661-6596, E-ISSN 1422-0067, Vol. 24, no 15, article id 12316
Article in journal (Refereed) Published
Abstract [en]
Over the last decade, the zebrafish has emerged as an important model organism for behavioural studies and neurological disorders, as well as for the study of metabolic diseases. This makes zebrafish an alternative model for studying the effects of energy disruption and nutritional quality on a wide range of behavioural aspects. Here, we used the zebrafish model to study how obesity induced by overfeeding regulates emotional and cognitive processes. Two groups of fish (n = 24 per group) were fed at 2% (CTRL) and 8% (overfeeding-induced obesity, OIO) for 8 weeks and tested for anxiety-like behaviour using the novel tank diving test (NTDT). Fish were first tested using a short-term memory test (STM) and then trained for four days for a long-term memory test (LTM). At the end of the experiment, fish were euthanised for biometric sampling, total lipid content, and triglyceride analysis. In addition, brains (eight per treatment) were dissected for HPLC determination of monoamines. Overfeeding induced faster growth and obesity, as indicated by increased total lipid content. OIO had no effect on anxiety-like behaviour. Animals were then tested for cognitive function (learning and memory) using the aversive learning test in Zantiks AD units. Results show that both OIO and CTRL animals were able to associate the aversive stimulus with the conditioned stimulus (conditioned learning), but OIO impaired STM regardless of fish sex, revealing the effects of obesity on cognitive processes in zebrafish. Obese fish did not show a deficiency in monoaminergic transmission, as revealed by quantification of total brain levels of dopamine and serotonin and their metabolites. This provides a reliable protocol for assessing the effect of metabolic disease on cognitive and behavioural function, supporting zebrafish as a model for behavioural and cognitive neuroscience.
Place, publisher, year, edition, pages
MDPI, 2023. Vol. 24, no 15, article id 12316
Keywords [en]
obesity, overfeeding, fat, BMI, memory, anxiety, monoamines, zebrafish
National Category
Neurosciences
Identifiers
URN: urn:nbn:se:uu:diva-510088DOI: 10.3390/ijms241512316ISI: 001046285000001PubMedID: 37569692OAI: oai:DiVA.org:uu-510088DiVA, id: diva2:1792114
Funder
Swedish Research Council, VR-NT11 2017-03779
Note
De två sista författarna delar sistaförfattarskapet.
2023-08-282023-08-282023-08-28Bibliographically approved