Pineal indoles stimulate the gene expression of immunomodulating cytokines

Male C57 mice received 10 consecutive daily intraperitoneal injections of m elatonin, 5-methoxytryptamine or 5-methoxytryptophol (5mg/kg body weight). Control mice received the alcoholic saline vehicle. All mice were sacrifice d 24 hours after the last injection. Following extraction of RNA from perit oneal exudate cells (PEC) and splenocytes, the level of gene expression was analyzed with the reverse transcription-polymerase chain reaction (RT-PCR) . The results revealed that melatonin up-regulated the level of gene expres sion of transforming growth factor-beta (TGF-beta), macrophage-colony stimu lating factor (M-CSF), tumor necrosis factor-alpha (TNF-alpha) and stem cel l factor (SCF) in PEG, and the level of gene expression of interleukin-1 be ta (IL-1 beta), M-CSF, TNF-alpha, interferon-gamma (IFN-gamma) and SCF in s plenocytes. 5-Methoxytryptamine augmented the level of gene expression of T GF-beta, M-CSF and SCF in PEC, and the level of gene expression of IL-1 bet a, TNF-alpha, IFN-gamma, M-CSF and SCF in splenocytes. 5-Methoxytryptophol elevated the level of gene expression of TNF-alpha, IL-1 beta, TGF-beta and M-CSF in PEC, and the level of gene expression of inducible nitric oxide s ynthase (iNOS), IL-1 beta, M-CSF, TNF-alpha, IFN-gamma and SCF in splenocyt es.