1.Hypericum Perforatum Decreased Hippocampus TNF-alpha and Corticosterone Levels with No Effect on Kynurenine/Tryptophan Ratio in Bilateral Ovariectomized Rats.
Wesam M EL-BAKLY ; Amany H HASANIN
The Korean Journal of Physiology and Pharmacology 2014;18(3):233-239
The present study was designed to investigate the effect Hypericum Perforatum (HP), on behavioral changes, corticosterone, TNF-alpha levels and tryptophan metabolism and disposition in bilateral ovariectomized rats compared to 17alpha -ethinylestradiol. Behavioral analysis by measuring immobility time in forced swimming test and open field test, serum and hippocampal corticosterone and TNF-alpha along with hippocampal kynurenine/tryptophan ratio were determined in mature ovariectomized rats treated orally either by HP at three different doses 125, 250, and 500 mg/kg/day or by 17alpha-ethinylestradiol 30 microg/kg/day for 30 days. Ovariectomized rats showed significant increase in immobility time in the forced swimming test. Along with elevation in serum and hippocampal TNF-alpha and corticosterone levels associated with significant increase in hippocampal kynurenine/tryptophan ratio. Immobility time in the forced swimming test was decreased in rats treated by different doses of HP in a dose dependent manner and 17alpha-ethinylestradiol with no concomitant changes in the open field test. Only Rats treated with HP exhibited significant decrease in the elevated serum and hippocampal TNF-alpha and corticosterone, which couldn't explain the associated insignificant effect on hippocampaus kynurenine/tryptophan ratio in comparison to ovariectomized untreated rats. It is concluded that increased tryptophan metabolism toward kynurenine secondary to elevated corticosterone and TNF-alpha might be one of the pathohphysiological mechanisms that could explain depression like state observed in this rat model. Further, the observed attenuating effect of HP on TNF-alpha and corticosterone could contribute in its antidepressant effect in this animal model by other ways than their effects on tryptophan-kynurenine metabolism pathway.
Animals
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Corticosterone*
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Depression
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Hippocampus*
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Hypericum*
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Kynurenine
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Metabolism
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Models, Animal
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Physical Exertion
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Rats*
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Tryptophan
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Tumor Necrosis Factor-alpha*