Figure 1

Experimental design and animal monitoring. (a) Animals were fed either a high-fat (HFD) or a standard (STD) diet for 12 weeks before being treated with vehicle (VEH) or a 0.2% linoleic acid (LA) solution for 5 weeks. The animal’s body weight and consummatory behavior were monitored during the entire experiment. The effect of the regimen and LA supplementation on emotional behavior was evaluated during the last week of the experiment through a battery of tests: the splash test (ST), the nestlet shredding test (NST), the novelty-supressed feeding (NSF) task, and the light–dark box (LDB) test. Animals were then sacrificed for IBA-1 immunofluorescence staining. Created with BioRender.com. (b) All animals progressively gained weight during the experiment, and mice fed a HFD weighed significantly more than their control counterparts (STD) from the sixth week of the differential regimen. However, 5 weeks of LA supplementation did not affect the body weight of animals in either the HFD or the STD group. (c) A general effect of the diet on the weekly food intake (Kcal) was evidenced, with HFD mice consuming significantly more calories than control animals. Besides, LA supplementation did not significantly impact food intake in either obese (HFD-LA vs. HFD-VEH) or non-obese animals (STD-LA vs. STD-VEH). (d) Sustained fat intake significantly influenced the weekly beverage intake in mice, with HFD individuals drinking a significantly lower volume than control animals. However, LA supplementation did not influence this behavior in either obese (HFD-LA vs. HFD-VEH) or non-obese animals (STD-LA vs. STD-VEH). Values plotted are mean ± SEM (n = 10 per group). *, p < 0.05; **, p < 0.01; ***, p < 0.001; ****, p < 0.0001; ns, not significant.