The Reactivation Effect Of Resveratrol On Latent HIV And Its Mechanism Of Action

The application of highly active antiretroviral therapy(HAART)has successfully transformed acquired immune deficiency syndrome from a deadly disease into a chronic and controllable disease.However,once cessation of the therapy would lead to a sudden rebound of viremia because of the presence of latent HIV reservoirs.The "shock and kill" strategy aims at leading to an HIV functional cure by awakening latent HIV in latently infected cells while preventing the spread of infection by implementing HAART,ultimately resulting in elimination of the activated cells due to viral cytopathic effects or the host immune response.Nowadays,the development of highly efficacious and safe latency reversing agents is the major topic of AIDS cure research.Resveratrol is a natural product existing in many plants species,especially abundant in red wine.Resveratrol has been reported previously to be capable to reactivate latent HIV.However,its reactivation effect on latent HIV and the underlying mechanism involved remains poorly defined.In this study,we verified the reactivation effect of resveratrol on HIV latency through a variety of methods including flow cytometry,quantitative RT-PCR and Western blotting,and investigate the molecular mechanisms involved in resveratrol-mediated reactivation through using J-Lat A2 cells as a primary cell model.The reactivation effect of resveratrol on latent HIV was verified by using various HIV latency cell models including J-Lat A2,J-Lat 10.6 and ACH2 cells.XTT assay was used to investigate the cytotoxicity of resveratrol in these HIV latency cell models,Jurkat T cells and human peripheral blood mononuclear cells(PBMCs).The results showed that resveratrol exhibited minimal cytotoxicity to these cells.To further evaluate the safety of resveratrol,the effect of resveratrol on global T cell activation was evaluated.The results showed that resveratrol did not influence the expression of T cell activation biomarkers CD25 and CD69 in human peripheral blood mononuclear cells,which revealed that resveratrol did not cause global T cell activation.Additionally,synergistic activation of the latent HIV reservoirs was observed under co-treatment with resveratrol and conventional LRAs prostratin,JQ1 or SAHA.On the basis of the reactivation effect of resveratrol on latent HIV,the reactivation effects of resveratrol derivatives(triacetyl resveratrol,dihydroresveratrol and resveratrol trimethyl ether,piceatannol,pterostilbene and polydatin)on latent HIV in J-Lat A2 cells were further evaluated.The results showed that triacetyl resveratrol induced a similar reactivation effect on latent HIV with resveratrol and also had a synergistic effect with prostratin,JQ1 or SAHA on the reactivation of HIV from latency,while other derivatives slightly influenced HIV transcription.By analyzing the structure-activity relationship,we supposed that the hydroxyl group in the meta-position of the benzene ring and the double bond between two benzene rings might be critical for maintaining the pharmacological activity.To substantiate the mechanism of action of resveratrol,various methods including Western blotting,flow cytometry and chromatin immunoprecipation were used.Mode of action studies showed resveratrol-mediated reactivation from latency did not involve the activation of SIRT1.However,resveratrol induced transcription initiation and elongation to reactivate latent HIV by increasing histone acetylation and activating heat shock factor(HSF1)and P-TEFb.In summary,resveratrol is a potent antagonist of HIV latency through increasing histone acetylation,activating HSF1 and p-TEFb without global T cell activation.Besides,resveratrol shows synergistic effects with conventional latency reversing agents prostratin,JQ1 or SAHA.