20.500.12556/RUL-131155 Ostreolysin A/pleurotolysin B and equinatoxins structure, function and pathophysiological effects of these pore-forming proteins Acidic ostreolysin A/pleurotolysin B (OlyA/PlyB, formerly known as ostreolysin (Oly), and basic 20 kDa equinatoxins (EqTs) are cytolytic proteins isolated from the edible mushroom Pleurotus ostreatus and the sea anemone Actinia equina, respectively. Both toxins, although from different sources, share many similar biological activities: (i) colloid-osmotic shock by forming pores in cellular and artificial membranes enriched in cholesterol and sphingomyelin; (ii) increased vascular endothelial wall permeability in vivo and perivascular oedema; (iii) dose-dependent contraction of coronary vessels; (iv) haemolysis with pronounced hyperkalaemia in vivo; (v) bradycardia, myocardial ischemia and ventricular extrasystoles accompanied by progressive fall of arterial blood pressure and respiratory arrest in rodents. Both types of toxins are haemolytic within nanomolar range concentrations, and it seems that hyperkalaemia plays an important role in toxin cardiotoxicity. However, it was observed that the haemolytically more active EqT III is less toxic than EqT I, the most toxic and least haemolytic EqT. In mice, EqT II is more than 30 times more toxic than OlyA/PlyB when applied intravenously. These observations imply that haemolysis with hyperkalaemia is not the sole cause of the lethal activity of both toxins. Additional mechanisms responsible for lethal action of the two toxins are direct effects on heart, coronary vasoconstriction and related myocardial hypoxia. In this review, we appraise the pathophysiological mechanisms related to the chemical structure of OlyA/PlyB and EqTs, as well as their toxicity. ostreolysin A/pleurotolysin B equinatoxins pore-forming proteins biological effects pore forming cytotoxic proteins relative biological effectiveness true false true Angleški jezik Ni določen Članek v reviji 2021-09-23 08:25:42 2021-09-23 08:25:42 2022-09-10 04:10:18 0000-00-00 00:00:00 2017 0 0 10 str. iss. 4, art. 128 Vol. 9 2017 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 577 2072-6651 10.3390/toxins9040128 4296570 RAZ_Frangez_Robert_2017.pdf RAZ_Frangez_Robert_2017.pdf 1 84726958D768606E5ED26CB5AF04B280 8b701eb73e22fadf841cb305669938e9046e1cfdaeead402e9d96a6b57c46678 309ed4f6-1c37-11ec-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=148415 http://www.mdpi.com/2072-6651/9/4/128 1 ceb7cd4a-1c36-11ec-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=148414 Veterinarska fakulteta Medicinska fakulteta 0 0 0