The metabolic and neuroinflammatory changes induced by consuming a cafeteria diet are age-dependent

Abstract

Objectives: To compare the effects of a palatable cafeteria diet on serum parameters and neuroinflammatory markers of young and aged female Wistar rats.

Methods: Three-month-old (young) and 18-month-old (aged) female Wistar rats had access to a cafeteria diet (Caf-Young, Caf-Aged) or a standard chow diet (Std-Young, Std-Aged).

Results: The Caf-Young group showed a higher food consumption, weight gain, visceral fat depot, serum insulin and leptin levels, and the insulin resistance index (HOMA-IR) than the Std-Young group. The Caf-Aged group exhibited an increase in interleukin-1 levels in the cerebral cortex and hippocampus. The number of GFAP-positive cells did not differ between the groups, but there was a diet effect in the cerebral cortex and an age effect in the hippocampus. Phospho-tau expression did not differ between the groups.

Discussion: The 3- and 18-month-old rats responded differently to a cafeteria diet. Insulin and leptin levels are elevated in young animals fed a cafeteria diet, whereas aged animals are prone to neuroinflammation (indicated by an increase in interleukin-1β levels). A combination of hypercaloric diet and senescence have detrimental effects on the inflammatory response in the brain, which may predispose to neurological diseases.

Keywords:

• Cafeteria diet
• Aging
• Neuroinflammation
• Obesity
• Interleukin-1β
• Insulin resistance
• Leptin resistance
• Female rats

ORCID

Renata Padilha Guedes http://orcid.org/0000-0002-4456-767X

Additional information

Funding

This work was supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, grant number 477421/2013-0). D.T. received a scholarship from CNPq, and A.L.C. received a postdoctoral PNPD scholarship from CAPES. M.F.M.R. received a CNPq 2 Researcher Productivity Grant.