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Hypericum perforatum chronic treatment affects cognitive parameters and brain neurotrophic factor levels
Samira S Valvassori1,2, Cenita Borges1, Daniela V Bavaresco1,2
1Laboratório de Neurociências, Programa de Pós-Graduação em Ciências da Saúde (PPGCS), Unidade Acadêmica de Ciências da Saúde (UNASAU), Universidade do Extremo Sul Catarinense (UNESC), Criciúma, SC, Brazil.
Revista Brasileira De Psiquiatria (Sao Paulo, Brazil : 1999)
|August 16, 2018
Summary
Long-term hypericum (Hypericum perforatum) administration impairs cognitive functions and reduces neurotrophic factors in rats, with more pronounced effects observed in females.
Area of Science:
- Neuroscience
- Pharmacology
- Behavioral Science
Background:
- Hypericum perforatum, commonly known as St. John's Wort, is a herbal remedy with reported effects on mood.
- The impact of hypericum on cognitive functions and underlying neurobiological mechanisms, particularly sex-dependent differences, requires further investigation.
Purpose of the Study:
- To investigate the effects of chronic hypericum administration on cognitive behavior in male and female rats.
- To assess the impact of hypericum on key neurotrophic factors, including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and glial cell-line derived neurotrophic factor (GDNF), in specific brain regions.
Main Methods:
- Wistar rats (male and female) were administered hypericum or a placebo (water) daily via gavage for 28 days.
- Cognitive performance was evaluated using the open-field test, novel object recognition test, and step-down inhibitory avoidance test.
- Levels of NGF, BDNF, and GDNF were quantified in the hippocampus and frontal cortex.
Main Results:
- Hypericum significantly impaired short- and long-term aversive memory acquisition in male rats.
- Female rats exhibited deficits in immediate, short-term, and long-term memory acquisition.
- Hypericum reduced the object recognition index in males and impaired new object recognition in females. Decreased BDNF was observed in the hippocampus of both sexes, and NGF was reduced in females.
Conclusions:
- Chronic administration of hypericum leads to significant cognitive impairment in rats.
- The observed cognitive deficits may be linked to a reduction in hippocampal and cortical neurotrophic factor levels.
- Cognitive impairment induced by hypericum was more severe in female rats compared to males.
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