Characterization of cognitive deficits in spontaneously hypertensive rats, accompanied by brain insulin receptor dysfunction

Scientific paper - Original scientific paper

• Author: Edna Grünblatt
• Author: Jasmin Bartl
• Author: Diana-Iulia Iuhos
• Author: Ana Knezović
• Author: Vladimir Trkulja
• Author: Peter Riederer
• Author: Susanne Walitza
• Author: Melita Šalković-Petrišić
• Author's institution: University of Zagreb; School of Medicine
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Basic Medical Sciences

Abstract (english)

BACKGROUND

The spontaneously hypertensive rat (SHR) has been used to model changes in the central nervous system associated with cognitive-related disorders. Recent human and animal studies indicate a possible relationship between cognitive deficits, insulin resistance and hypertension. We aimed to investigate whether cognitively impaired SHRs develop central and/or peripheral insulin resistance and how their cognitive performance is influenced by the animal's sex and age as well as strains used for comparison (Wistar and Wistar-Kyoto/WKY). ----- METHODS

Three and seven-month-old SHR, Wistar, and WKY rats were studied for their cognitive performance using Morris Water Maze (MWM) and Passive Avoidance tests (PAT). Plasma glucose and insulin were obtained after oral glucose tolerance tests. Cerebral cortex, hippocampus, and striatum status of insulin-receptor (IR) β-subunit and glycogen synthase kinase-3β (GSK3β) and their phosphorylated forms were obtained via ELISA. ----- RESULTS

SHRs performed poorly in MWM and PAT in comparison to both control strains but more pronouncedly compared to WKY. Females performed poorer than males and 7-month-old SHRs had poorer MWM performance than 3-month-old ones. Although plasma glucose levels remained unchanged, plasma insulin levels were significantly increased in the glucose tolerance test in 7-month-old SHRs. SHRs demonstrated reduced expression and increased activity of IRβ-subunit in cerebral cortex, hippocampus, and striatum with different regional changes in phospho/total GSK3β ratio, as compared to WKYs. ----- CONCLUSION

Results indicate that cognitive deficits in SHRs are accompanied by both central and peripheral insulin dysfunction, thus allowing for the speculation that SHRs might additionally be considered as a model of insulin resistance-induced type of dementia.

• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review
• Publication version: Published version
• Journal title: Journal of Molecular Psychiatry
• Numbering: vol. 3, no. 1, p. 6
• p-ISSN: 2049-9256
• DOI: https://doi.org/10.1186/s40303-015-0012-6
• URN:NBN: urn:nbn:hr:105:621118
• Publication: 2015-06-04
• Document URL: https://doi.org/10.1186/s40303-015-0012-6
• Type of resource: Text
• Access conditions: Open access
• Created on: 2024-03-28 08:11:52