1a,1b-dihomo Prostaglandin E2 (PGE2) is a rare polyunsaturated fatty acid first identified in extracts of sheep vesicular gland microsomes, known to contain COX, incubated with adrenic acid . 1a,1b-dihomo PGE2 has also been identified in conditioned media of RAW 264.7 macrophages stimulated with endotoxin and arachidonic acid . This product is thought to be produced by elongation of AA to adrenic acid, which is then metabolized sequentially by COX and PGE synthase.
16,16-Dimethyl prostaglandin E2 is an orally active vertebrate Hematopoietic stem cells homeostasis critical regulator. It can act through EP2 EP4 and has an interaction with the Wnt pathway.
Bimatoprost is the Allergan trade name for 17-phenyl trinor prostaglandin F2α ethyl amide (17-phenyl trinor PGF2α ethyl amide), an F-series PG analog which has been approved for use as an ocular hypotensive drug. Oxidation of the C-15 hydroxyl group produces 15-keto-17-phenyl trinor PGF2α ethyl amide. 15-keto-17-phenyl trinor PGF2α ethyl amide is a potential metabolite of 17-phenyl trinor PGF2α ethyl amide when 17-phenyl trinor PGF2α ethyl amide is administered to intact animals. No pharmacological studies on 15-keto-17-phenyl trinor PGF2α ethyl amide have been reported.
PGBx is a mixture of oligomers of PGB1 with a molecular weight of 1,000-1,500. It has antioxidant and free radical trapping activity that was first studied in isolated mitochondria.1 PGBx has anti-inflammatory and cytoprotective activity which may be attributed to inhibition of the 14 kDa sPLA2.2,3 At a dose of 1 mg/kg, PGBx significantly reduces the incidence of ulcers in rats.2References1. Polis, B.D., Polis, E., and Kwong, S. Protection and reactivation of oxidative phosphorylation in mitochondria by a stable free-radical prostaglandin polymer (PGBΧ). Proceedings of the National Academy of Sciences of the United States of America 76, 1598-1602 (1979).2. Kumashiro, R., Devlin, T.M., Kholoussy, A.M., et al. Prostaglandin BΧ in the prevention of stress ulcers in rats. International Surgery 70, 247-250 (1985).3. Franson, R.C., Rosenthal, M.D., and Regelson, W. Mechanism(s) of cytoprotective and anti-inflammatory activity of PGB1 oligomers: PGBx has potent anti-phospholipase A2 and anti-oxidant activity. Prostaglandins, Leukotrienes and Essential Fatty Acids 43, 63-70 (1991). PGBx is a mixture of oligomers of PGB1 with a molecular weight of 1,000-1,500. It has antioxidant and free radical trapping activity that was first studied in isolated mitochondria.1 PGBx has anti-inflammatory and cytoprotective activity which may be attributed to inhibition of the 14 kDa sPLA2.2,3 At a dose of 1 mg/kg, PGBx significantly reduces the incidence of ulcers in rats.2 References1. Polis, B.D., Polis, E., and Kwong, S. Protection and reactivation of oxidative phosphorylation in mitochondria by a stable free-radical prostaglandin polymer (PGBΧ). Proceedings of the National Academy of Sciences of the United States of America 76, 1598-1602 (1979).2. Kumashiro, R., Devlin, T.M., Kholoussy, A.M., et al. Prostaglandin BΧ in the prevention of stress ulcers in rats. International Surgery 70, 247-250 (1985).3. Franson, R.C., Rosenthal, M.D., and Regelson, W. Mechanism(s) of cytoprotective and anti-inflammatory activity of PGB1 oligomers: PGBx has potent anti-phospholipase A2 and anti-oxidant activity. Prostaglandins, Leukotrienes and Essential Fatty Acids 43, 63-70 (1991).
Isoprostanes are produced by the non-enzymatic, free radical peroxidation of phospholipid-esterified arachidonic acid. They have been used as biomarkers of oxidative stress, but they also have been found to have potent biological activity. ent-8-iso-15(S)-Prostaglandin F2α (ent-8-iso-15(S)-PGF2α) is a potent vasoconstrictor of porcine retinal and brain microvessels with EC50 values of 15 and 24 nM, respectively. This isoprostane is about ten-fold more potent than 8-iso-PGF2α in a whole blood platelet aggregation inhibition assay.
Enzymatically-derived prostaglandin E2 (PGE2) is an optically pure compound whereas PGE2 derived from the free radical-catalyzed peroxidation of arachidonate is a racemic mixture. Ent-PGE2 is the opposite enantiomer of PGE2. Significant amounts of racemic PGE2 (rac-PGE2) are generated in vitro and in vivo in settings of oxidative stress via the isoprostane pathway. A proposed mechanism for the formation of rac-PGE2 involves the base catalyzed equilibration from 15-E2t-isoprostane (8-iso-PGE2), generated from the 15-H2t-isoprostane endoperoxide.
16,16-dimethyl PGA2 is a metabolism-resistant analog of PGA2 with a prolonged in vivo half-life. It inhibits the proliferation of Sendai virus in cultured African green monkey kidney cells by >90% at a concentration of 4 μg ml. Daily infusion of 10 μg of 16,16-dimethyl PGA2 methyl ester into mice infected with influenza A virus increased survival by 40%. Similar treatment of mice inoculated with erythroleukemia cells delayed tumor growth and increased survival time.