Short communication: Methamphetamine treatment increases in vitro and in vivo HIV replication

Abstract

To delineate the mechanistic basis for the epidemiological association between methamphetamine use and accelerated progression to AIDS, we evaluated the direct in vitro and in vivo effects of methamphetamine on HIV-1 replication. Methamphetamine administration significantly increased HIV-1 production by both HIV-infected monocytes and CD4 T lymphocytes in vitro. In addition, in vivo methamphetamine treatment increased HIV production and viremia in mice transgenic for a replication-competent HIV provirus and human cyclin T1. Methamphetamine activated transcription of the HIV long terminal repeat (LTR) regulatory region, was associated with nuclear translocation of NF-kappaB. Our results provide further insights into the mechanisms by which methamphetamine accelerates disease course in HIV-infected individuals.

Figures

FIG. 1.

Meth administration increases HIV production in human monocytes and activates the HIV LTR. (A) Eight days after infection and exposure to the indicated concentrations of meth, HIV production was measured by determining the concentration of p24 antigen in the culture supernatant. Cells were cultured in triplicate and the experiment was repeated three times. Data shown represent the mean ± standard error (SEM) of fold increase in p24 production induced by the indicated dose of meth from three independent experiments. (B) The TZM-bl reporter cell line was exposed to the indicated dose of meth for 2 days and then luciferase activity was measured. Data shown represent the mean ± SEM of fold increase in luciferase activity induced by the indicated dose of meth from two independent experiments. The Student's t test for unpaired data was used for all statistical comparisons made. Significance was assigned to p values of <0.05. (C) Monocytes were exposed to the indicated concentration of meth, and 2 h later nuclear extracts were prepared and analyzed for NF-κB p65. Nuclear extracts from LPS-stimulated monocytes cultured and processed in parallel are included as positive controls. Results are presented as specific absorbance (450 nm) of the ELISA assay and are means for two independent experiments with SEM shown.

FIG. 1.

Meth administration increases HIV production in human monocytes and activates the HIV LTR. (A) Eight days after infection and exposure to the indicated concentrations of meth, HIV production was measured by determining the concentration of p24 antigen in the culture supernatant. Cells were cultured in triplicate and the experiment was repeated three times. Data shown represent the mean ± standard error (SEM) of fold increase in p24 production induced by the indicated dose of meth from three independent experiments. (B) The TZM-bl reporter cell line was exposed to the indicated dose of meth for 2 days and then luciferase activity was measured. Data shown represent the mean ± SEM of fold increase in luciferase activity induced by the indicated dose of meth from two independent experiments. The Student's t test for unpaired data was used for all statistical comparisons made. Significance was assigned to p values of <0.05. (C) Monocytes were exposed to the indicated concentration of meth, and 2 h later nuclear extracts were prepared and analyzed for NF-κB p65. Nuclear extracts from LPS-stimulated monocytes cultured and processed in parallel are included as positive controls. Results are presented as specific absorbance (450 nm) of the ELISA assay and are means for two independent experiments with SEM shown.

FIG. 2.

Meth administration increases in vitro and in vivo HIV production by JR-CSF mouse leukocytes. (A) Purified bone marrow-derived monocytes from JR-CSF/hu-CycT1 mice were cultured in quadruplicate in the presence of GM-CSF and the indicated dose of meth. After 8 days, HIV-1 production was measured by determining p24 antigen concentration present in the culture supernatant. Data shown represent the mean ± SEM of fold increase in p24 values in JR-CSF/huCycT1 murine monocytes from two independent experiments. (B) JR-CSF/hu-CycT1 mice were treated with PBS or meth at a dose of 5 mg/kg for six doses, or at a dosage range of 5–7 mg/kg for 2 weeks (administered as 5 mg/kg for the first week, then 6.0, 6.5, and 7.0 mg/kg for the last three doses). HIV p24 antigen production in lysed splenocytes harvested after treatment was quantified as described. Data shown represent the mean ± SEM of fold increase in p24 antigen of the spleen of meth-treated mice compared to PBS-treated mice. There were five mice in each group and three independent experiments were performed. (C) JR-CSF/hu-CycT1 mice were treated with either PBS or meth (5 mg/kg for six does over 2 weeks). HIV RNA copy number in mouse serum was quantified using the Versant HIV-1 RNA 3.0 assay (bDNA). Data shown represent the mean ± SEM of HIV RNA (copies/ml) initially and after completion of the indicated treatment. There were five mice in each group and the experiment was performed twice.

FIG. 2.

Meth administration increases in vitro and in vivo HIV production by JR-CSF mouse leukocytes. (A) Purified bone marrow-derived monocytes from JR-CSF/hu-CycT1 mice were cultured in quadruplicate in the presence of GM-CSF and the indicated dose of meth. After 8 days, HIV-1 production was measured by determining p24 antigen concentration present in the culture supernatant. Data shown represent the mean ± SEM of fold increase in p24 values in JR-CSF/huCycT1 murine monocytes from two independent experiments. (B) JR-CSF/hu-CycT1 mice were treated with PBS or meth at a dose of 5 mg/kg for six doses, or at a dosage range of 5–7 mg/kg for 2 weeks (administered as 5 mg/kg for the first week, then 6.0, 6.5, and 7.0 mg/kg for the last three doses). HIV p24 antigen production in lysed splenocytes harvested after treatment was quantified as described. Data shown represent the mean ± SEM of fold increase in p24 antigen of the spleen of meth-treated mice compared to PBS-treated mice. There were five mice in each group and three independent experiments were performed. (C) JR-CSF/hu-CycT1 mice were treated with either PBS or meth (5 mg/kg for six does over 2 weeks). HIV RNA copy number in mouse serum was quantified using the Versant HIV-1 RNA 3.0 assay (bDNA). Data shown represent the mean ± SEM of HIV RNA (copies/ml) initially and after completion of the indicated treatment. There were five mice in each group and the experiment was performed twice.