Hydroxytyrosol (HT; 3,4-dihydroxyphenyl ethanol) is an
important
functional polyphenol in olive oil. Our study sought to evaluate the
protective effects and underlying mechanisms of HT on obesity-induced
cognitive impairment. A high-fat and high-fructose-diet-induced obese
mice model was treated with HT for 14 weeks. The results show that
HT improved the learning and memory abilities and enhanced the expressions
of brain-derived neurotrophic factors (BDNFs) and postsynaptic density
proteins, protecting neuronal and synaptic functions in obese mice.
Transcriptomic results further confirmed that HT improved cognitive
impairment by regulating gene expression in neural system development
and synaptic function-related pathways. Moreover, HT treatment alleviated
neuroinflammation in the brain of obese mice. To sum up, our results
indicated that HT can alleviate obesity-induced cognitive dysfunction
by enhancing BDNF expression and alleviating neuroinflammation in
the brain, which also means that HT may become a potentially useful
nutritional supplement to alleviate obesity-induced cognitive decline.