Protectin conjugates in tissue regeneration 1 (PCTR1) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid . DHA is oxidized to 16S,17S-epoxy-protectin, which is then converted to PCTR1 by glutathione S-transferase. PCTR1 levels increase during resolution of acute microbial-induced peritonitis in mice. PCTR1 (30 ng, i.p.) administration 12 hours post-infection increases macrophage numbers and activity and shortens the resolution phase of inflammation by 57%. It also reduces the levels of PGE2 , PGD2 , and TXB2 in peritoneal exudates.
Maresin conjugates in tissue regeneration 3 (MCTR3) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid in macrophages. DHA is oxidized to maresin 1 , which is converted to MCTR1 by glutathione S-transferase Mu 4 or leukotriene C4 synthase, then to MCTR2 by γ-glutamyl transferase, and to MCTR3 by dipeptidase. MCTR3 accelerates tissue regeneration in planaria (1 and 100 nM) approximately as potently as MCTR2 and more potently than MCTR1. Pretreatment with MCTR3 prior to E. coli administration in mice reduces neutrophil infiltration, shortens the inflammatory resolution period, and increases phagocytosis of E. coli by macrophages. When administered at a dose of 100 ng 12h post E. coli infection in a mouse model of peritonitis, MCTR3 selectively reduces the amount of the eicosanoids PGD2 , PGE2 , PGF2α , and TXB2 in the exudate.
Maresin conjugates in tissue regeneration 1 (MCTR1) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid in macrophages at the site of inflammation. DHA is oxidized to maresin 1 , which is then converted to MCTR1 by glutathione S-transferase Mu 4 or leukotriene C4 synthase. MCTR1 accelerates tissue regeneration in planaria (1 and 100 nM). Pretreatment with MCTR1 (50 ng mouse, i.p.) prior to E. coli administration reduces neutrophil infiltration, shortens the inflammatory resolution period, and increases phagocytosis of E. coli by macrophages. When administered at a dose of 100 ng 12h post E. coli infection in a mouse model of peritonitis, MCTR1 reduces the amount of eicosanoids in the exudate.
Benastatin A is a polyketide synthase-derived benastatin that has been found inStreptomycesand has diverse biological activities.1,2,3It inhibits glutathione S-transferase (GST; Ki= 5 μM for the rat liver enzyme).2Benastatin A is active against several bacteria, including methicillin-resistantS. aureus(MRSA; MIC = 3.12 μg ml). It induces apoptosis and cell cycle arrest at the G1 G0phase in Colon 26 mouse colon cancer cells when used at concentrations of 20 and 16 μM, respectively.3 1.Xu, Z., Schenk, A., and Hertweck, C.Molecular analysis of the benastatin biosynthetic pathway and genetic engineering of altered fatty acid-polyketide hybridsJ. Am. Chem. Soc.129(18)6022-6030(2007) 2.Aoyagi, T., Aoyama, T., Kojima, F., et al.Benastatins A and B, new inhibitors of glutathione S-transferase, produced by Streptomyces sp. MI384-DF12. I. Taxonomy, production, isolation, physico-chemical properties and biological activitiesJ. Antibiot. (Tokyo)45(9)1385-1390(1992) 3.Kakizaki, I., Ookawa, K., Ishikawa, T., et al.Induction of apoptosis and cell cycle arrest in mouse colon 26 cells by benastatin AJpn. J. Cancer Res.91(11)1161-1168(2000)
Maresin conjugates in tissue regeneration 2 (MCTR2) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid in macrophages at the site of inflammation. DHA is oxidized to maresin 1 , which is converted to MCTR1 by glutathione S-transferase Mu 4 or leukotriene C4 synthase then to MCTR2 by γ-glutamyl transferase. MCTR2 accelerates tissue regeneration in planaria (1 and 100 nM). Pretreatment with MCTR2 prior to E. coli administration reduces neutrophil infiltration, shortens the inflammatory resolution period, and increases phagocytosis of E. coli by macrophages. When administered at a dose of 100 ng 12h post E. coli infection in a mouse model of peritonitis, MCTR2 selectively reduced the amount of the eicosanoids PGD2 and PGF2α in the exudate.
Benastatin C is a polyketide synthase-derived benastatin that has been found inStreptomycesand has diverse biological activities.1,2It inhibits glutathione S-transferase (GST; IC50= 24 μg ml for the rat liver enzyme).2Benastatin C also inhibits the esterase activity of isolated porcine pancreatic lipase (IC50= 10 μg ml). It increases LPS- or concanavalin A-induced blastogenesis of isolated mouse spleen lymphocytes in a concentration-dependent manner. 1.Xu, Z., Schenk, A., and Hertweck, C.Molecular analysis of the benastatin biosynthetic pathway and genetic engineering of altered fatty acid-polyketide hybridsJ. Am. Chem. Soc.129(18)6022-6030(2007) 2.Aoyama, T., Kojima, F., Yamazaki, T., et al.Benastatins C and D, new inhibitors of glutathione S-transferase, produced by Streptomyces sp. MI384-DF12. Production, isolation, structure determination and biological activitiesJ. Antibiot. (Tokyo)46(5)712-718(1993)