PAF (C16) (Synonyms: Platelet-activating Factor C-16)

PAF(C16) is a membrane-derived phospholipid, It is also a platelet activating factor and a ligand for PAF G protein-coupled receptor (PAFR). PAF(C16) is a potent MAPK and MEK/ERK activator. PAF(C16) can induce cell exosmosis in a dose-dependent manner and improve vascular permeability. PAF(C16) inhibits Caspase-dependent cell apoptosis by activating PAFR and has anti-apoptotic effect^[1-4].

PAF(C16) (10, 25, 50, and 100 μg/ml; 2 h) inhibits M. smegmatis and M. bovis BCG growth in a dose-dependent manner^[2]. PAF(C16) (10 nM; 24 h) can destroy the decreased levels of IL-25 and IL-33 in cells caused by 5α-DHT ^[5]. 500 nM PAF(C16) increased the numbers of phenotypic Haematopoietic stem/progenitor cell (HSPC) and induced cell cycling of HSPC^[6].

PAF(C16) (5 mg/kg; orally administrated every 3 days) significantly inhibited the effect of 5α-DHT on airway hyperreactivity (AHR) ^[4]. PAF(C16) (0.5-10 ng/kg) given as a bolus into the renal arterial circulation of pentobarbital sodium-anesthetized male Wistar rats caused systemic hypotension and produced a dose-dependent increase in renal blood flow ^[7].

References:

[1]. Vadas, P, Perelman, B, et,al. Platelet-activating factor, histamine, and tryptase levels in human anaphylaxis. J. Allergy Clin. Immunol. 131, 144–149. doi: 10.1016/j.jaci.2012.08.016

[2]. Riaz MS, Kaur A, et,al. Direct Growth Inhibitory Effect of Platelet Activating Factor C-16 and Its Structural Analogs on Mycobacteria. Front Microbiol. 2018 Sep 11;9:1903. doi: 10.3389/fmicb.2018.01903. PMID: 30258409; PMCID: PMC6143801.

[3]. Ryan SD, Harris CS, et,al. Heterogeneity in the sn-1 carbon chain of platelet-activating factor glycerophospholipids determines pro- or anti-apoptotic signaling in primary neurons. J Lipid Res. 2008 Oct;49(10):2250-8. doi: 10.1194/jlr.M800263-JLR200. Epub 2008 Jun 12. PMID: 18550892.

[4]. Bögershausen N, Tsai IC, et,al. RAP1-mediated MEK/ERK pathway defects in Kabuki syndrome. J Clin Invest. 2015 Sep;125(9):3585-99. doi: 10.1172/JCI80102. Epub 2015 Aug 17. PMID: 26280580; PMCID: PMC4588287.

[5]. Xia T, Ma J, et,al. Androgen receptor suppresses inflammatory response of airway epithelial cells in allergic asthma through MAPK1 and MAPK14. Hum Exp Toxicol. 2022 Jan-Dec;41:9603271221121320. doi: 10.1177/09603271221121320. PMID: 35982617.

[6]. Sun Q, Zhou Y, et,al. MEK1 activation enhances the ex vivo proliferation of haematopoietic stem/progenitor cell. Cell Biochem Funct. 2022 Jan;40(1):79-89. doi: 10.1002/cbf.3677. Epub 2021 Dec 2. PMID: 34855220.

[7]. Handa RK, Strandhoy JW, et,al. Platelet-activating factor is a renal vasodilator in the anesthetized rat. Am J Physiol. 1990 Jun;258(6 Pt 2):F1504-9. doi: 10.1152/ajprenal.1990.258.6.F1504. PMID: 2360650.