Abstract: Sponges biosynthesize α-methoxylated fatty acids with unusual biophysical and biological properties and in some cases they display enhanced anticancer activities. However, the antiprotozoal properties of the α-methoxylated fatty acids have been less studied. In this work, we describe the total synthesis of (5Z,9Z)-(±)-2-methoxy-5, 9-eicosadienoic acid (1) and its acetylenic analog (±)-2-methoxy-5,9-eicosadiynoic acid (2), and report that they inhibit (EC50 values between 31 and 22 µM) the Leishmania donovani DNA topoisomerase IB enzyme (LdTopIB). The inhibition of LdTopIB (EC50 = 53 µM) by the acid (±)-2-methoxy-6-icosynoic acid (12) was studied as well. The potency of LdTopIB inhibition followed the trend 2 > 1 > 12, indicating that the effectiveness of inhibition depends on the degree of unsaturation. All of the studied α-methoxylated fatty acids failed to inhibit the human topoisomerase IB enzyme (hTopIB) at 100 µM. However, the α-methoxylated fatty acids were capable of inhibiting an active but truncated LdTopIB with which camptothecin (CPT) cannot interact suggesting that the methoxylated fatty acids inhibit LdTopIB with a mechanism different from that of CPT. The diunsaturated fatty acids displayed low cytotoxicity towards Leishmania infantum promastigotes (EC50 values between 260 and 240 µM), but 12 displayed a better cytotoxicity towards Leishmania donovani promastigotes (EC50 = 100 µM) and a better therapeutic index.
Keywords: methoxylated fatty acids; leishmania donovani; 2-methoxy-5,9-eicosadienoic acid; topoisomerase IB
Export to BibTeX
MDPI and ACS Style
Carballeira, N.M.; Montano, N.; Alvarez-Velilla, R.; Prada, C.F.; Reguera, R.M.; Balaña-Fouce, R. Synthesis of Marine α-Methoxylated Fatty Acid Analogs that Effectively Inhibit the Topoisomerase IB from Leishmania donovani with a Mechanism Different from that of Camptothecin. Mar. Drugs 2013, 11, 3661-3675.
Carballeira NM, Montano N, Alvarez-Velilla R, Prada CF, Reguera RM, Balaña-Fouce R. Synthesis of Marine α-Methoxylated Fatty Acid Analogs that Effectively Inhibit the Topoisomerase IB from Leishmania donovani with a Mechanism Different from that of Camptothecin. Marine Drugs. 2013; 11(10):3661-3675.
Carballeira, Néstor M.; Montano, Nashbly; Alvarez-Velilla, Raquel; Prada, Christopher F.; Reguera, Rosa M.; Balaña-Fouce, Rafael. 2013. "Synthesis of Marine α-Methoxylated Fatty Acid Analogs that Effectively Inhibit the Topoisomerase IB from Leishmania donovani with a Mechanism Different from that of Camptothecin." Mar. Drugs 11, no. 10: 3661-3675.