TY - JOUR
T1 - Effects of dietary fat manipulation on cognition in mice and rats
T2 - Protocol for a systematic review and meta-analysis
AU - Ramage, Fiona J.
AU - Clewlow, Alexander S.
AU - Williams, Lynda M.
AU - MacLeod, Malcolm R.
AU - Langston, Rosamund F.
N1 - Funding Information:
Funding FR is part of the EASTBIO Doctoral Training Partnership funded by the Biotechnology and Biological Sciences Research Council (BBSRC, part of UK Research and Innovation).
Publisher Copyright:
© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.
PY - 2020/11/19
Y1 - 2020/11/19
N2 - Introduction and objective The Western diet that comprises high levels of long-chain saturated fats and sugar is associated not only with metabolic disorders such as obesity and type 2 diabetes but also has been recently linked to brain changes and cognitive dysfunction. However, in animal studies, reported effects are variable, and the mechanisms underlying these effects are unclear. In the proposed review, we aim to summarise the diverse evidence of the effects of so-called â € high-fat' and ketogenic diets on behavioural measures of cognition in postweaning mice and rats, relative to animals on standard diets and to determine potential underlying mechanisms of high-fat diet-induced effects. Search strategy A comprehensive search strategy was designed to retrieve studies reporting use of a high-fat or ketogenic diet in postweaning mice and rats that included cognitive assessments. Three databases (Medline, SCOPUS and Web of Science) were searched and 4487 unique references were retrieved. Screening and annotation Studies were screened for inclusion by two independent reviewers, with 330 studies retained for analysis. Characteristics of disease model choice, experimental design, intervention use and outcome assessment are to be extracted using the Systematic Review Facility (http://syrf.org.uk/) tool. Studies will be assessed for study quality and risk of bias and confidence of mechanistic involvement. Data management and reporting For cognitive outcomes, effect sizes will be calculated using normalised mean difference and summarised using a random effects model. The contribution of potential sources of heterogeneity to the observed effects of diet on cognition will be assessed using multivariable meta-regression, with partitioning of heterogeneity as a sensitivity analysis. A preliminary version of this protocol was published on 9 April 2019 on the Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies website (http://www.dcn.ed.ac.uk/camarades/research.html%23protocols). Ethics and dissemination No ethical approval is required as there are no subjects in the proposed study.
AB - Introduction and objective The Western diet that comprises high levels of long-chain saturated fats and sugar is associated not only with metabolic disorders such as obesity and type 2 diabetes but also has been recently linked to brain changes and cognitive dysfunction. However, in animal studies, reported effects are variable, and the mechanisms underlying these effects are unclear. In the proposed review, we aim to summarise the diverse evidence of the effects of so-called â € high-fat' and ketogenic diets on behavioural measures of cognition in postweaning mice and rats, relative to animals on standard diets and to determine potential underlying mechanisms of high-fat diet-induced effects. Search strategy A comprehensive search strategy was designed to retrieve studies reporting use of a high-fat or ketogenic diet in postweaning mice and rats that included cognitive assessments. Three databases (Medline, SCOPUS and Web of Science) were searched and 4487 unique references were retrieved. Screening and annotation Studies were screened for inclusion by two independent reviewers, with 330 studies retained for analysis. Characteristics of disease model choice, experimental design, intervention use and outcome assessment are to be extracted using the Systematic Review Facility (http://syrf.org.uk/) tool. Studies will be assessed for study quality and risk of bias and confidence of mechanistic involvement. Data management and reporting For cognitive outcomes, effect sizes will be calculated using normalised mean difference and summarised using a random effects model. The contribution of potential sources of heterogeneity to the observed effects of diet on cognition will be assessed using multivariable meta-regression, with partitioning of heterogeneity as a sensitivity analysis. A preliminary version of this protocol was published on 9 April 2019 on the Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies website (http://www.dcn.ed.ac.uk/camarades/research.html%23protocols). Ethics and dissemination No ethical approval is required as there are no subjects in the proposed study.
UR - http://www.scopus.com/inward/record.url?scp=85105954580&partnerID=8YFLogxK
U2 - 10.1136/bmjos-2020-100108
DO - 10.1136/bmjos-2020-100108
M3 - Review article
AN - SCOPUS:85105954580
SN - 2398-8703
VL - 4
JO - BMJ Open Science
JF - BMJ Open Science
IS - 1
M1 - e100108
ER -