title: Hyperglycemia exacerbates antiretroviral drug combination induced blood-brain barrier endothelial toxicity.
abstract: In this study, we sought to investigate how concomitant hyperglycemia influences the impact of combination antiretroviral therapy on blood-brain barrier (BBB) endothelial function. Immortalized human brain microvascular endothelial cell line (hCMEC/D3) was exposed to azidothymidine (AZT; a nucleoside reverse transcriptase inhibitor) and/or indinavir (IND; protease inhibitor) in normal glycemic (5.5mM) or hyperglycemic (HG; 25mM) media containing D-glucose for 24-72h. Cellular reactive oxygen species (ROS) and mitochondria-specific superoxide levels were assayed in addition to membrane potential to determine the extent of mitochondrial dysfunction. Nrf2 expression was analyzed by immunofluorescence. Our results indicated a significant increase in BBB endothelial toxicity (decreased ATP) by HG and AZT+IND with progression of time (24-72h). Concurrent HG and antiviral drug combination synergistically elevated BBB endothelial ROS induced by either condition alone. Further, HG and AZT+IND mutually interact to elicit a pronounced increase in mitochondrial superoxide levels post 24h (vs. either condition alone or controls). In addition, HG and AZT+IND complemented each other to induce potential loss of mitochondrial membrane potential. While HG or AZT+IND alone for 24h increased Nrf2 nuclear distribution, co-exposure conditions induced a potential loss of Nrf2 expression/nuclear translocation in BBB endothelium. In summary, our data strongly suggest that antiretroviral drug combination potentially interacts with concomitant HG and triggers exacerbated mitochondrial dysfunction and BBB endothelial toxicity, possibly through dysregulation of Nrf2 signaling. Thus, this study warrants the critical need for safety evaluation and monitoring of neurovascular complications of HAART regimens in HIV-infected diabetic patient cohort.
authors.affiliation: Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, 1300 S. Coulter Street, Amarillo, TX 79106, USA.
authors.forename: Shikha
authors.initials: S
authors.lastname: Prasad
authors.affiliation: Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, 1300 S. Coulter Street, Amarillo, TX 79106, USA.
authors.forename: Ravi K
authors.initials: RK
authors.lastname: Sajja
authors.affiliation: Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, 1300 S. Coulter Street, Amarillo, TX 79106, USA.
authors.forename: Mohammad A
authors.initials: MA
authors.lastname: Kaisar
authors.affiliation: Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, 1300 S. Coulter Street, Amarillo, TX 79106, USA. Electronic address: luca.cucullo@ttuhsc.edu.
authors.forename: Luca
authors.initials: L
authors.lastname: Cucullo
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000998:Antiviral Agents / Q000493:pharmacokinetics*; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000187:drug effects*; D005434:Flow Cytometry; D005947:Glucose / Q000494:pharmacology*; D006801:Humans; D019469:Indinavir / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism; D013997:Time Factors; D015215:Zidovudine / Q000494:pharmacology*
chemical_list: D000998:Antiviral Agents; D017382:Reactive Oxygen Species; D013481:Superoxides; D015215:Zidovudine; D019469:Indinavir; D000255:Adenosine Triphosphate; D005947:Glucose
keywords: BBB; Diabetes; HAART; Mitochondria; Nrf2; Oxidative stress; Zidovudine