Introduction:
In psychic depression, St. John's wort (Hypericum perforatum L.) extracts are an established herbal treatment option. As depression has been linked to an inflammatory response, the combined antioxidant and anti-inflammatory properties [1] are suggested to contribute to the antidepressant effects [2] by normalization of an overactive hypothalamic-pituitary-adrenal axis [3].
Objective:
Thus, the aim of our investigations was to determine the effects of a Hypericum extract, STW 3-VI (extraction medium ethanol 80%, DER 3-6:1), on the protection of differentiated mouse hippocampal HT22 cells against the cytotoxic effects of glutamate or NMDA and the possible anti-inflammatory properties on LPS-activated macrophages (MΦ).
Material and Methods:
Differentiated HT22 cells were pre-treated with STW 3-VI to investigate the protective effects against glutamate or NMDA cytotoxicity. The anti-inflammatory properties of STW 3-VI were evaluated by quantification of the TNF release on LPS activated PMA-differentiated THP 1 MΦ using ELISA assay and the mRNA expression of TNF and IL-6 by qRT-PCR. Glutamate or NMDA (0.1mM) induced 30% cytotoxicity in HT22 cells.
Results and Discussion:
Pre-incubation (24h) with STW 3-VI improved the viability by 30% compared to the control. Pre-treatment (48h) of LPS activated MΦ with STW 3-VI induced a significant lowering (54%, 64% and 53%) of TNF release. QRT-PCR revealed that 48 h pre-treatment with STW 3-VI inhibited the mRNA expression of IL-6 and TNF respectively by LPS-activated MΦ.
Conclusion:
STW 3-VI protects hippocampal cells from glutamate or NMDA induced cytotoxicity and activates the anti-inflammatory defense by in hibition of the cytokine production by MΦ. These effects are in accordance with the therapeutic use of STW3-VI in depression.
References:
1. Breyer A et al. Phytomedicine 2007, 14: 250-255
2. Denke A et al. Drug Res 2000, 50: 415-419
3. Gastpar M, Singer A, Zeller K. Pharmacopsychiatry 2006, 39: 66-75
4. Grundmann O, Kelber O, Butterweck V. Planta Medica 2006, 72: 1366-1371