Nanoflow-nanospray mass spectrometry metabolomics reveals disruption of the urinary metabolite profiles of HIV-positive patients on combination antiretroviral therapy

Background: The use of combination antiretroviral therapy (cART) has substantially improved the outlook for patients with HIV infection. However, lifelong exposure to cART is also associated with adverse metabolic changes and an enhanced risk of renal, hepatic and cardiovascular dysfunction. This study investigated disruptions of the urinary metabolome of cART-exposed patients, thereby furthering our understanding of some of the side effects of pharmaceutical intervention. Methods: HIV-positive patients were recruited from an HIV clinic and divided into cART-naive and cART-exposed groups. HIV-negative patients were recruited from a sexual health clinic. All 89 subjects were white males. Targeted biochemistry analyses were performed on plasma samples. Urine samples were collected following an overnight fast and analysed with a highly sensitive untargeted metabolomic method using nanoflow/nanospray liquid chromatography-time of flight mass spectrometry. Datasets were analysed using projection modelling to detect metabolite markers of cART exposure. Results: Metabolites or parent compounds of all cART drugs were detected in urine extracts of all but one of the cART-exposed patients confirming adherence to the pharmaceutical regimen. Analysis of urine samples from patients on cART revealed significant reductions in selected bile acids, lipid, nucleoside and androgen metabolites. However, plasma concentrations of free or conjugated testosterone were unchanged indicating possible disruption of androgen transport or excretion in urine of patients on cART. Conclusions: Discovery-based metabolomics reveals the potential to identify novel markers of cART intervention and metabolite disruption in HIV-positive patients, which may enable the efficacy, compliance and side effects of these pharmaceutical mixtures to be investigated.