Anti-HIV drugs have primarily focused on inhibition of essential viral enzymes such as reverse transcriptase or viral protease. However, these drugs fail in long-term treatment of HIV-1 due to viral drug resistance. Alternative targets of attack of the HIV-1 would be targeting host cell transcription factors. Transcription of HIV-1 viral genes is uniquely dependent on both viral proteins and host cell factors. The hypothesis of this proposal is that iron chelators may inhibit HIV-1 replication by affecting host cell transcription factors. To address the hypothesis, the iron chelators, desferrioxamine, 2-hydroxy-1-naphthylaldehyde isonicotinoylhydrazone (311) and ICL670 will be utilized to chelate intracellular iron.
The first aim of the proposal will investigate the effect of the iron chelators on HIV-1 gene expression and replication in several cell lines, including HeLa, HeLa-MAGI, CEM T, 293T and HIV-1 infected lymphocytic cells. HIV-1 transcription and viral replication will be measured with the use of reporters or infection with pseudotyped HIV-1 viruses. The extent of the iron chelation will be evaluated by measuring labile Iron. Also, Lactate DeHydrogenase (LDH)-Cytotoxicity Assay will be utilized to test if chelators render any damage to the cells. The second part of the proposal will focus on understanding the mechanism for HIV-1 inhibition. Our lab has previously shown that cyclin dependent kinase 2 (CDK2)/cyclin T1 is important for HIV-1 transcription. Therefore, the second aim will study if iron chelators inhibit expression and cellular activities of the cyclin dependent kinase 9 (CDK9) and CDK2. Tat phosphorylation by CDK2/cyclin E will be measured to determine if iron chelators inhibit the activity of CDK2. The ability of HIV-1 to replicate is also shown to depend on nuclear factor (NF)-kappa ? activation, mediating inducible HIV-1 gene transcription. NF-kappa ? activation, regulating proviral transcription, can be influenced by iron. Thus, the effect of the iron chelators on NF-kappa ? level, activation and target genes will also be studied. These findings will provide information in the search for alternative therapeutic approaches that are hopefully more effective and efficient to treat HIV-1. Iron chelators could add to improve the treatment of HIV disease.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Predoctoral Individual National Research Service Award (F31)
Project #
5F31HL090025-02
Application #
7587384
Study Section
Special Emphasis Panel (ZRG1-IMM-L (29))
Program Officer
Werner, Ellen
Project Start
2008-03-15
Project End
2011-03-14
Budget Start
2009-03-15
Budget End
2010-03-14
Support Year
2
Fiscal Year
2009
Total Cost
$41,176
Indirect Cost
Name
Howard University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
056282296
City
Washington
State
DC
Country
United States
Zip Code
20059