Effect of short and long term high-fat diet on contextual fear memory.

HERRERA GUADALUPE; LASAGA MERCEDES; SCIMONELLI TERESA

Córdoba

Congreso; XXXIII Congress of the Argentine Society for Research in Neuroscience; 2018

Sociedad Argentina de Investigación en Neurociencias (SAN)

High-fat diet (HFD) consumption is associated not only with an increased risk of metabolic and cardiovascular diseases, but also with cognitive deficit, depression and anxiety disorders. The HFD effects on the central nervous system could be related to neuroinflammation, being the hippocampus one of the most vulnerable brain regions to HFD-induced alterations.We explored whether short-term (5 days) or long term (6 weeks) HFD consumption would serve as a neuroinflammatory trigger, leading to cognitive deficits. HFD impaired fear contextual (hippocampal dependent) memory if it is consumed during a long time, but not after 5 days. Interestingly, it has been described that in the hippocampus, HFD (during a short period), even as little as 3 days, is not directly inflammatory and only sensitizes cells to over-respond to future inflammatory stimuli. Accordingly, the intraperitoneal injection of LPS in rats that received HFD during 5 days impaired memory consolidation.The treatment with α-MSH (0,1ug/0.25ul) in dorsal hippocampus could not reverse the effect of long term HFD in contextual fear memory. Considering that α-MSH is a potent anti-inflammatory peptide and that previous results indicated that α-MSH could reverse the effect of IL-1β on memory consolidation and reconsolidation, we will continue studying a possible α-MSH effect, with different doses and treatment protocols.