Modulation of Gene Expression in Human Macrophages Treated with the Anti- Leishmania Pentavalent Antimonial Drug Sodium Stibogluconate

Abstract

Within the mammalian host, Leishmania donovani is an obligatory intracellular protozoan parasite that resides and multiplies exclusively in the phagolysosomes of macrophages. Leishmania control relies primarily on chemotherapy, with the mainstay being pentavalent antimony (SbV) complexed to carbohydrates in the form of sodium stibogluconate (Pentostam) or meglumine antimoniate (Glucantime). The mode of action of SbV is still not known precisely. To explore the effect of SbV on macrophage gene expression, a microarray analysis was performed using Affymetrix focus arrays to compare gene expression profiles in noninfected and L. donovani-infected THP-1 monocytic cells treated or not treated with sodium stibogluconate. Under our experimental conditions, SbV changed the expression of a few host genes, and this was independent of whether cells were infected or not infected with Leishmania. Leishmania infection had a greater effect on the modulation of host gene expression. Statistical analyses have indicated that the expression of eight genes was modified by at least twofold upon SbV treatment, with six genes upregulated and two genes downregulated. One gene whose expression was affected by SbV was the heme oxygenase gene HMOX-1, and this change was observed both in the monocytic cell line THP-1 and in primary human monocyte-derived macrophages. Another pathway that was affected was the glutathione biosynthesis pathway, where the expression of the glutamate-cysteine ligase modifier subunit was increased upon SbV treatment. Our analysis has suggested that, under our experimental conditions, the expression of a few genes is altered upon SbV treatment, and some of these encoded proteins may be implicated in the yet-to-be-defined mode of action of SbV.

Knockdown of Host Antioxidant Defense Genes Enhances the Effect of Glucantime on Intracellular Leishmania braziliensis in Human Macrophages

“…Similar results have been reported for the THP-1 human macrophage cell line and confirmed in human MDMs, suggesting that Sb V induces oxidative stress in human macrophages (20). In our study, overexpression of the CAT, GPX2, HMOX1, and TRX genes confirms the effect of Sb V and possibly Sb III in inducing oxidative stress.…”

“…In those studies, antimony compounds, as well as Leishmania infection, were demonstrated to modulate the expression of the GSR gene, which is involved in the reduction of glutathione, and that of the ABCB6 and SLC7A11 genes, which encode drug transporters involved in drug distribution or drug reduction in human macrophages (20,22). We also found upregulation of genes involved in the glutathione biosynthesis pathway, antioxidant defense, and drug transporters of the ABCB family, highlighting the expression levels observed for GSTP1, GSS, TRX, and ABCB5.…”

4-Amino Bis-Pyridinium Derivatives as Novel Antileishmanial Agents

“…THP-1 cells were grown at 37°C and 5% CO 2 in RPMI 1640 supplemented with 10% iFBS, 2 mM glutamate, 100 U/ml penicillin, and 100 g/ml streptomycin. Cells, at 3 ϫ 10 4 /well in 96-well plates, were differentiated to macrophages with 20 ng/ml of PMA treatment for 48 h followed by 24 h of culture in fresh medium (10). The cellular toxicity of all compounds was determined using the colorimetric MTT-based assay (9), as described previously for Leishmania promastigotes, except for the incubation temperature, which was 37°C in this case.…”

Snapshot Profiling of the Antileishmanial Potency of Lead Compounds and Drug Candidates against Intracellular Leishmania donovani Amastigotes, with a Focus on Human-Derived Host Cells

“…Drug transporters at the host cell level have been linked to clinical responses to antimonial treatment and drug resistance (10,11,27). Modulation of gene expression profiles by SSG has also been demonstrated in vitro, and increased levels of glutathione were measured in SSG-treated cells compared to untreated host cells (28). It is possible that differences in the response to oxidative stress, production of cytokines, expression of drug transport- ers, or a combination of these factors between different host cells account for the host cell-dependent phenotype of antimonial drug action.…”