Abstract (eng)
Overweight is a worldwide problem, which is, among others, a result of an overconsumption of energy. Capsaicin increases, Ca2+-dependently via activation of the TRPV1-receptor, the release of the neurotransmitters serotonin and dopamine. A stimulation of these neurotransmitters is associated with reduced food intake, resulting in weight loss. This thesis aimed to confirm the neurotransmitter-stimulating effect of capsaicin in vitro in neuronal SH-SY5Y cells and to identify a less pungent structural related compound with comparable effects. Natural alkamides were screened and the most effective compound was compared to capsaicin. Also the effect on serotonin and dopamine receptor gene expression and the impact on possible target receptors were studied. 1 µM Capsaicin most potently increased the release of serotonin by 73 ± 51 % and 10 µM the release of dopamine by 1196 ± 535 %. 0.1 µM trans-pellitorine, the most effective alkamide, increased the release of serotonin by 40 ± 26 % and the release of dopamine by 83 ± 55 %. The effects of 0.1 µM trans-pellitorine on serotonin (140 ± 26 %) and dopamine (183 ± 55 %) release were comparable to capsaicin (112 ± 22 % or 221 ± 35 %). 0.1 µM trans-pellitorine led to a time-dependent regulation of the serotonin receptors 5-HT2A, 5-HT1A, 5-HT1B and dopamine receptors D1 und D2. 0.1 µM trans-pellitorine increased the expression of TRPA1 mRNA and reduced those of CNR1 mRNA. Trans-pellitorine increased, possibly via a TRPA1-mediated, Ca2+-dependent mechanism, the release of the neurotransmitter serotonin and dopamine in neuronal SH-SY5Y cells.