, 2010), and the issue of utilization of UGT-cleared integrase inhibitors for HIV/AIDS during fetal development and early infancy, given the low UGT activity during this phase (Strassburg et al., 2002). Glucuronidation studies of compound 1 and, for comparison, raltegravir, were determined in pooled human liver microsomes verified to contain UGT 1A1, 1A4, 1A6, 1A9 and 2B7. Compound 1 was not a substrate for these key UGTs in human liver microsomes or for specific cDNA-expressed UGT isozymes, UGT1A1 Panobinostat datasheet and UGT1A3 (Table 4). Furthermore, in the kinetic studies in human liver microsomes, there was no indication of the

activation of UGT isozymes. In contrast, raltegravir was a substrate for UGT (Fig. 4), which is consistent with previously reported data (Kassahun et al., 2007). We also examined the possible competitive inhibition of UGTs by compound 1 using 4-methylumbelliferone (4-MU), a substrate for multiple isoforms of UGT. However, no evidence for significant competitive inhibition of the key UGT isozymes

1A1, 1A6, 1A9 and 2B7 was found (IC50 > 300 μM). In addition, compound 1 was not an inhibitor of another key UGT isozyme, namely UGT1A4. In summary, we have discovered a new HIV integrase Selleck PS341 inhibitor (1), that exhibits significant antiviral activity against a diverse set of HIV-1 isolates, as well as against HIV-2 and SIV and that displays low in vitro cytotoxicity. It has a favorable resistance and related drug susceptibility profile. Compound 1 is not a substrate for key human UGT isoforms, which is of particular relevance, both in HIV co-infection therapeutics and in HIV treatments during fetal development and early infancy. Finally, Cyclin-dependent kinase 3 the CYP isozyme profile of compound 1 suggests that it is not expected to interfere with normal human CYP-mediated metabolism. Support of this research by the National

Institutes of Health (R01 AI 43181 and NCRR S10-RR025444) is gratefully acknowledged. The contents of this paper are solely the responsibility of the authors and do not necessarily represent the official views of the NIH. One of us (VN) also acknowledges support from the Terry Endowment (RR10211184) and from the Georgia Research Alliance Eminent Scholar Award (GN012726). The in vitro anti-HIV data were determined by Southern Research Institute, Frederick, MD, using federal funds from the Division of AIDS, NIAID, NIH, under contract HHSN272200700041C entitled “Confirmatory In Vitro Evaluations of HIV Therapeutics.” We acknowledge the help of Dr. Byung Seo and Dr. Pankaj Singh in the early structure-activity studies. We thank Dr. John Bacsa of Emory University for the X-ray crystal structure data. “
“Viral hemorrhagic fever (VHF) designates a group of diseases caused by enveloped, single-stranded RNA viruses belonging to four different families of viruses that include the Arenaviridae, Bunyaviridae, Filoviridae and Flaviviridae.