AIDS Research

Ascorbate effect on cytokine stimulation of HIV production.

Nutrition 1995 Sep-Oct;11(5 Suppl):684-7 (ISSN: 0899-9007)

Harakeh S; Jariwalla RJ Virology and Immunodeficiency Research Program, Linus Pauling Institute of Science and Medicine, Palo Alto, California 94306, USA.

We have recently shown that ascorbic acid (AA) suppresses the production of HIV in a latently infected T-lymphocytic cell line (ACH-2) following stimulation with the tumor promoter, PMA. To evaluate the effect of ascorbic acid on virus activation following treatment with inflammatory cytokine, we tested tumor necrosis factor alpha (TNF-alpha) whose levels are elevated in patients with HIV/AIDS. ACH-2 cultures, pretreated with various nontoxic concentrations of ascorbate or AZT were stimulated for 2 h with TNF-alpha, and incubated further with fresh supplements of ascorbate or AZT. At 24 to 48 h post-treatment, the Reverse Transcriptase (RT) activity released into culture supernatant was determined. Results showed that TNF-alpha alone caused approximately 13- to 16-fold stimulation in the level of extracellular RT. Pretreatment with ascorbic acid at 200 micrograms/ml caused a little more than about 2- to 4-fold reduction in extracellular RT levels. Most remarkably, exposure to 300 micrograms/ml ascorbate resulted in approximately 5- to 10-fold lowering of the extra-cellular RT titer. In contrast, no significant suppression in extracellular RT levels was seen with concentrations of AZT in the range of 1-5 micrograms/ml.