saquinavir and Inflammation

HIV-associated neurocognitive disorder (HAND) is prevalent in people living with HIV, despite the use of antiretroviral therapy (ART). Although several risk factors have been proposed to be related to HAND, substantial effort has been made to explore the neurotoxic effects of ART on HAND. HIV protease inhibitor (PI), an essential component of ART, has neurotoxicity in vivo and in vitro, which can contribute to the development of HAND. However, the pathogenesis of PI-associated neurotoxicity remains unclear. Here, we explored whether PI treatment is a potential pathogenic factor for HAND and elucidated its potential mechanisms. In our study, U87 cells were exposed to PIs, including lopinavir (LPV), ritonavir (RTV), darunavir, indinavir, and saquinavir at different concentrations, we found that LPV, LPV/RTV, and saquinavir attenuated autophagy in U87 cells, the results of Western blot showed that the expression of p62 dramatically was elevated and the level of LC3II/LC3I was decreased. Moreover, comparative transcriptomics revealed the involvement of the inflammatory response in the physiological activities of U87 cells exposed to LPV, with differential genes significantly enriched in the p38 MAPK signaling pathway. In the following study, we verified the results from RNA-sequence using the liquid chip technique, qRT-PCR, Elisa, and western blots, which suggested that LPV induced inflammatory response and the p38 MAPK pathway was involved in this process. Collectively, we demonstrated that PIs attenuated the involvement of astrocyte autophagy in inflammation via the p38 MAPK pathway, providing new insights into the mechanism of HAND.

Topics: Astrocytes; Autophagy; HIV Infections; HIV Protease; HIV Protease Inhibitors; Humans; Inflammation; p38 Mitogen-Activated Protein Kinases; Ritonavir; Saquinavir

This protocol describes microsphere-based protease assays for use in flow cytometry and high-throughput screening. This platform measures a loss of fluorescence from the surface of a microsphere due to the cleavage of an attached fluorescent protease substrate by a suitable protease enzyme. The assay format can be adapted to any site or protein-specific protease of interest and results can be measured in both real time and as endpoint fluorescence assays on a flow cytometer. Endpoint assays are easily adapted to microplate format for flow cytometry high-throughput analysis and inhibitor screening.

Topics: Animals; Biotinylation; Flow Cytometry; Fluorescence Resonance Energy Transfer; Green Fluorescent Proteins; High-Throughput Screening Assays; Humans; Inflammation; Kinetics; Microspheres; Peptide Hydrolases; Peptides; Reproducibility of Results; Temperature