Cyclic zinc-dithiocarbamate-S,S'-dioxide blocks CXCR4-mediated HIV-1 infection

Antiviral Potential of Selected N-Methyl-N-phenyl Dithiocarbamate Complexes against Human Immunodeficiency Virus (HIV)

Despite the use of highly active antiretroviral therapy approved by the United States Food and Drug Administration (FDA) for the treatment of human immunodeficiency virus (HIV) infection, HIV remains a public health concern due to the inability of the treatment to eradicate the virus. In this study, N-methyl-N-phenyl dithiocarbamate complexes of indium(III), bismuth(III), antimony(III), silver(I), and copper(II) were synthesized. The complexes were characterized by thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). The N-methyl-N-phenyl dithiocarbamate complexes were then evaluated for their antiviral effects against HIV-1 subtypes A (Q168), B (QHO.168), and C (CAP210 and ZM53). The results showed that the copper(II)-bis (N-methyl-N-phenyl dithiocarbamate) complex had a neutralization efficiency of 94% for CAP210, 54% for ZM53, 45% for Q168, and 63% for QHO.168. The silver(I)-bis (N-methyl-N-phenyl dithiocarbamate) complex showed minimal neutralization efficiency against HIV, while indium(III) and antimony(III) N-methyl-N-phenyl dithiocarbamate complexes had no antiviral activity against HIV-1. The findings revealed that copper(II)-bis (N-methyl-N-phenyl dithiocarbamate), with further improvement, could be explored as an alternative entry inhibitor for HIV.

The Versatility in the Applications of Dithiocarbamates

Dithiocarbamate ligands have the ability to form stable complexes with transition metals, and this chelating ability has been utilized in numerous applications. The complexes have also been used to synthesize other useful compounds. Here, the up-to-date applications of dithiocarbamate ligands and complexes are extensively discussed. Some of these are their use as enzyme inhibitor and treatment of HIV and other diseases. The application as anticancer, antimicrobial, medical imaging and anti-inflammatory agents is examined. Moreover, the application in the industry as vulcanization accelerator, froth flotation collector, antifouling, coatings, lubricant additives and sensors is discussed. The various ways in which they have been employed in synthesis of other compounds are highlighted. Finally, the agricultural uses and remediation of heavy metals via dithiocarbamate compounds are comprehensively discussed.

Zinc coupling potentiates anti-HIV-1 activity of baicalin

Baicalin (BA) has been shown with anti-HIV-1 activity. Zinc is a nutrient element. The anti-HIV-1 activity of zinc complex of baicalin (BA-Zn) in vitro was studied and compared with the anti-HIV-1 activities between BA and BA-Zn in the present study. Our results suggested that BA-Zn has lower cytotoxicity and higher anti-HIV-1 activity compared with those of BA in vitro. The CC50s of BA-Zn and BA were 221.52 and 101.73 microM, respectively. The cytotoxicity of BA-Zn was about 1.2-fold lower than that of BA. The BA and BA-Zn inhibited HIV-1 induced syncytium formation, HIV-1 p24 antigen and HIV-1 RT production. The EC50s of BA-Zn on inhibiting HIV-1 induced syncytium formation (29.08 microM) and RT production (31.17 microM) were lower than those of BA (43.27 and 47.34 microM, respectively). BA-Zn was more effective than BA in inhibiting the activities of recombinant RT and HIV-1 entry into host cells. Zinc coupling enhanced the anti-HIV-1 activity of baicalin.

Anti-HIV-1 peptides derived from partial amino acid sequences of CC-chemokine RANTES. Regulated upon activation, normal T-cell expressed and secreted

Fifteen acetyl-peptide-amides with partial amino acid sequences of RANTES (regulated upon activation, normal T-cell expressed and secreted), all Cys residues of which were substituted by Ala, were synthesized, and screened for anti-HIV-1 activity. Peptides corresponding to 1-10, 37-46, and 57-68 showed marked activity against CC-chemokine receptor 5-using HIV-1(JR-CSF) (% inhibition at 100 nM 69, 82, 76%, respectively). The results indicate that multiple regions, including the N-terminal part responsible for chemotactic activity, are involved in anti-HIV-1 activity of RANTES, yielding possible lead compounds for anti-HIV-1 agents.

Novel strategy for anti-HIV-1 action: selective cytotoxic effect of N-myristoyltransferase inhibitor on HIV-1-infected cells

N-myristoyltransferase (NMT) is essential for the survival of eukaryotes and the production of infectious human immunodeficiency virus type-1(HIV-1) by the host cell. In this study, we found decreases in the mRNA levels of human NMT isoforms and the NMT activities in the course of HIV-1 infection in the human T-cell line, CEM. Investigating the cytotoxic effect of the novel synthetic NMT inhibitors on the chronic HIV-1 infected T-cell line, CEM/LAV-1, and the uninfected CEM, revealed that the cytotoxic effect was significantly selective for CEM/LAV-1. This was thought to be due to the difference between the NMT levels of the cell lines. In this paper, we propose that NMT may be a candidate target for anti-HIV-1-infected-cell agents.

Down-regulation of N-myristoyl transferase expression in human T-cell line CEM by human immunodeficiency virus type-1 infection

The present study focuses on the expression level of N-myristoyl transferase (NMT) in the course of human immunodeficiency virus type-1 (HIV-1) infection. HIV-1 structural proteins were gradually expressed during the process of infection of the human T-cell line CEM, whereas the expression levels of NMT subsequently decreased under the same conditions. In addition, the chronically HIV-1-infected T-cell line CEM/LAV-1 exhibited low expression levels of NMT. We hypothesize that the decrease in the expression level of NMT due to HIV-1 infection may be related to the virus' strategy that leads to its persistent replication.

Chemokine receptors: emerging opportunities for new anti-HIV therapies

The chemokine receptors CCR5 and CXCR4 are G-protein coupled receptors (GPCRs) of the immune system and the major co-receptors required for entry of HIV into CD4(+) target cells. CCR5 is critical for both human immunodeficiency virus (HIV) disease transmission and progression, whereas CXCR4 may be very important in late stages of disease. Additional co-receptors have been shown to function under certain conditions in vitro but evidence of supporting roles in HIV disease is currently lacking. The sheer number of co-receptors potentially used by HIV and the complexity of co-receptors usage are major challenges confronting usage of these molecules as drug development targets. Balanced against this, is a long history of success by the pharmaceutical industry in developing small molecule antagonists for many other classes of GPCRs. In this review, we discuss the current state of understanding of the co-receptor-based antiviral agents designed to block viral entry. The therapeutic potential of this field will be judged from future studies on the efficacy of these novel inhibitors in clinical trials. The data so far obtained from a number of studies point to the potential clinical use of this emerging class of therapeutic agents. Here we review current progress in co-receptor-based antiretroviral drug development and discuss the potential advantages and disadvantages of this approach.

Myristoylation of human immunodeficiency virus type 1 gag protein is required for efficient env protein transportation to the surface of cells

Highly conserved amino acids in the N-terminal region of the human immunodeficiency virus type 1 (HIV-1) Pr55(gag) are recognized to be critical for the attachment of myristic acid. We previously reported that the env protein was not detected on the cell surface by blocking of N-myristoylation of Pr55(gag) with N-myristoyl glycinal diethylacetal. Here, we constructed a mutant by substituting the N-terminal glycine of Pr55(gag) with alanine to demonstrate that N-myristoylation of Pr55(gag) is required for efficient env protein transportation to the cell surface. The expression level of the env protein on the surface of Jurkat cells transfected with the myristoylation-defective phenotype was observed to be significantly reduced by electron microscopic analyses with a gold-labeled monoclonal antibody against the env protein. In addition, Jurkat cells transfected with the myristoylation-defective phenotype lost the ability of envelope-mediated cell-to-cell fusion. The results suggest that N-myristoylation of the HIV-1 gag protein is necessary for efficient env protein transportation to the cell surface.