Neuroprotective and memory-enhancing effects of Aloysia gratissima extract and rutin in an MPTP-induced model of Parkinson's disease.

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder worldwide and currently has no cure. Available treatments mainly alleviate symptoms but show limited long-term efficacy, underscoring the need for new therapeutic strategies. This work aimed to investigate the neuroprotective potential of Aloysia gratissima leaf extract and the flavonoid rutin on memory deficits, inflammatory markers, and neurotransmitter bioavailability in an MPTP-induced model of PD in rats. At 12-13 weeks of age Wistar rats were intranasally administered 1 mg of MPTP to induce PD-like symptoms. Animals were treated by oral gavage for 14 days with A. gratissima extract (100 or 200 mg/kg) or rutin (50 or 100 mg/kg). Behavioral evaluations included the social recognition and Y-maze tests on treatment days 7 and 14. After treatment, hippocampal and cortical levels of dopamine, serotonin, and inflammatory markers were quantified. MPTP exposure caused significant memory deficits, neurotransmitter depletion, and increased neuroinflammatory markers. Treatment with A. gratissima (200 mg/kg) or rutin (100 mg/kg) significantly reversed these effects, improving memory performance, restoring dopamine and serotonin levels, and reducing neuroinflammation. A. gratissima extract and rutin demonstrated potential neuroprotective activity in the MPTP model of PD, likely through anti-inflammatory and neurotransmitter-regulating mechanisms. These findings support their potential as alternative therapeutic strategies for PD management.