Protein Farnesyltransferase Inhibitors Exhibit Potent Antimalarial Activity
摘要:
New therapeutics to combat malaria are desperately needed. Here we show that the enzyme protein farnesyltransferase (PFT) from the malaria parasite Plasmodium falciparum (P. falciparum) is an ideal drug target. PFT inhibitors (PFTIs) are well tolerated in man, but are highly cytotoxic to P. falciparum. Because of their anticancer properties, PFTIs comprise a highly developed class of compounds. PFTIs are ideal for the rapid development of antimalarials, allowing "piggy-backing" on previously garnered information. Low nanomolar concentrations of tetrahydroquinoline (THQ)-based PFTIs inhibit P. falciparum PFT and are cytotoxic to cultured parasites. Biochemical studies suggest inhibition of parasite PFT as the mode of THQ cytotoxicity. Studies with malaria-infected mice show that THQ PFTIs dramatically reduce parasitemia and lead to parasite eradication in the majority of animals. These studies validate P. falciparum PFT as a target for the development of antimalarials and describe a potent new class of THQ PFTIs with antimalaria activity.
Second Generation Tetrahydroquinoline-Based Protein Farnesyltransferase Inhibitors as Antimalarials
作者:Pravin Bendale、Srinivas Olepu、Praveen Kumar Suryadevara、Vivek Bulbule、Kasey Rivas、Laxman Nallan、Brian Smart、Kohei Yokoyama、Sudha Ankala、Prakash Rao Pendyala、David Floyd、Louis J. Lombardo、David K. Williams、Frederick S. Buckner、Debopam Chakrabarti、Christophe L. M. J. Verlinde、Wesley C. Van Voorhis、Michael H. Gelb
DOI:10.1021/jm0703340
日期:2007.9.1
Substituted tetrahydroquinolines (THQs) have been previously identified as inhibitors of mammalian protein farnesyltransferase (PFT). Previously we showed that blocking PFT in the malaria parasite led to cell death and that THQ-based inhibitors are the most potent among several structural classes of PFT inhibitors (PFTIs). We have prepared 266 THQ-based PFTIs and discovered several compounds that inhibit the malarial enzyme in the sub- to low-nanomolar range and that block the growth of the parasite (P. falciparum) in the lownanomolar ran-e. This body of structure- activity data can be rationalized in most cases by consideration of the X-ray structure of one of the THQs bound to mammalian PFT together with a homology structural model of the malarial enzyme. The results of this study provide the basis for selection of antimalarial PFTIs for further evaluation in preclinical drug discovery assays.