Pentamidine (isethionate)

Pentamidine isethionate (MP-601205 isethionate) is an antimicrobial agent and interferes with DNA biosynthetics. Pentamidine isethionate inhibits parasite Leishmania infantum with an IC₅₀ of 2.5 μM. Pentamidine isethionate is a potent and selective protein tyrosine phosphatases (PTPases) and phosphatase of regenerating liver (PRL) inhibitor. Pentamidine isethionate has the potential for Gambian trypanosomiasis, antimony-resistant leishmaniasis, and Pneumocystis carinii pneumonia treatment. Antitumor and antibacterial activities^[1][2][3][4]. IC50 & Target:IC50: 2.5 μM (Leishmania infantum)^[2]
Protein tyrosine phosphatases (PTPases)^[1]
Phosphatase of regenerating liver (PRL)^[1] In Vitro: Pentamidine (0-10 µg/mL; 6 days; WM9, DU145, C4-2, Hey, WM480, and A549 cells) treatment inhibits the growth of cancer cells in a concentration-dependent manner^[1].
The cytotoxic properties of Pentamidine isethionate towards the promastigotes of the protozoan parasite Leishmania infantum is determined. The leishmanicidal activity of Pentamidine isethionate is 60 times higher after 72 h of incubation than that of Cisplatin. Pentamidine isethionate induces a higher amount of programmed cell death (PCD) than Cisplatin, which is associated with inhibition of DNA synthesis and cell-cycle arrest in the G2/M phase. Binding of Pentamidine isethionate to calf-thymus DNA (CT-DNA) induces conformational changes in the DNA double helix, consistent with a B-->A transition. The interaction of Pentamidine isethionate with ubiquitin leads to a 6% increase in the beta-sheet content of the protein^[2]. In Vivo: Pentamidine (0.25 mg/mouse; intramuscular injection; every 2 days; for 4 weeks; athymic nude mice) treatment markedly inhibits the growth of WM9 human melanoma tumors in nude mice^[1].