Melatonin (Synonyms: NSC 56423, NSC 113928, Regulin)

Melatonin is a hormone made by the pineal gland that can activates melatonin receptor. Melatonin plays a role in sleep and possesses important antioxidative and anti-inflammatory properties[1][2][3]. Melatonin is a novel selective ATF-6 inhibitor and induces human hepatoma cell apoptosis through COX-2 downregulation[4].

Melatonin increases the levels of activated PTEN, RSK-1, mTOR and AMPKα kinases, mildly inhibits ERK-1/2 phosphorylation and Bad phosphorylation, significantly inhibits phosphorylations of S6 Ribosomal Protein, 4E-BP1, GSK-3α and GSK-3β, and slightly increases PRAS40 phosphorylation in animals[1]. Melatonin ameliorates the neurotoxiciy and astrocyte activation induced by Aβ1-42 in the cerebral cortex. Melatonin also blocks the reduction in Reelin and Dab1 expression induced by Aβ1-42[2]. Melatonin treatment and lack of NLRP3-/- share similar inhibition of NF-κB and NLRP3 signaling pathway in mice. Melatonin treatment and lack of NLRP3-/- share some patterns of clock genes expression, and improve cardiomyocytes morphology in mice[3].

References:
[1]. Kilic U, et al. Particular phosphorylation of PI3K/Akt on Thr308 via PDK-1 and PTEN mediates melatonin's neuroprotective activity after focal cerebral ischemia in mice. Redox Biol. 2017 Apr 5;12:657-665
[2]. Hu C, et al. Neuroprotective effect of melatonin on soluble Aβ1-42-induced cortical neurodegeneration via Reelin-Dab1 signaling pathway. Neurol Res. 2017 Apr 7:1-1
[3]. Rahim I, et al. Melatonin administration to wild-type mice and non-treated NLRP3 mutant mice share similar inhibition of the inflammatory response during sepsis. J Pineal Res. 2017 Mar 31
[4]. Bu LJ, et al. Melatonin, a novel selective ATF-6 inhibitor, induces human hepatoma cell apoptosis through COX-2 downregulation. World J Gastroenterol. 2017 Feb 14;23(6):986-998.