HIV Protease Inhibitors Trigger Lipid Metabolism Dysregulation Through Endoplasmic Reticulum Stress and Autophagy

<p>HIV protease inhibitors (PI) are core components of Highly Active Antiretroviral Therapy (HAART). HIV PIs are extremely effective at suppressing viral load, but have been linked to lipodystrophy and dyslipidemia, which are major risk factors for cardiovascular disease. Recent studies indicate that activation of endoplasmic reticulum (ER) stress is an important cellular mechanism underlying HIV PI-induced dysregulation of lipid metabolism. However, the exact role of ER stress in HIV PI-associated lipodystrophy and dyslipidemia remains to be identified. Hepatocytes and adipocytes are important players in regulating lipid metabolism and the inflammatory state. Dysfunction of these two cell types is closely linked to various metabolic diseases. In this dissertation research, we aimed to define the role of activation of ER stress in HIV PI-induced dysregulation of lipid metabolism in adipocytes and hepatocytes and further identifty the potential molecular mechanisms. Both cultured and primary mouse adipocytes and hepatocytes were used to examine the effect of individual HIV PIs on ER stress activation and lipid metabolism. The results indicated that HIV PIs differentially activate ER stress through depletion of ER calcium stores, activating the unfolded protein response (UPR). UPR activation further lead to an alteration of cellular differentiation through downstream transcription factor CHOP. At the same time, HIV PIs also altered adipogenesis via differential regulation of the adipogenic transcription factor PPARγ. HIV PI-induced ER stress was closely linked to dysregulation of autophagy activation through CHOP, and upstream ATF-4, signaling pathways. In hepatocytes, the integrase inhibitor raltegravir abrogated HIV PI-induced lipid accumulation by inhibiting ER stress activation and dysregulation of autophagy pathway. Our studies suggest that both ER stress and autophagy are involved in HIV PI-induced dysregulation of lipid metabolism in adipocytes and hepatocytes. The key components of ER stress and autophagy signaling pathways are potential therapeutic targets for HIV PI-induced metabolic side effects in HIV HAART-treated patients.</p>

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Microbiology & Immunology

Year dc:date.available

2011

Author dc:creator

• Zha, Beth Shoshana

Contributors dc:contributor

• Huiping Zhou

• HIV Protease Inhibitors
• ER Stress
• Autophagy
• PPARγ
• adipocyte
• hepatocyte
• raltegravir
• Medicine and Health Sciences

Statement dc:rights

• © The Author

Identifier

https://scholarscompass.vcu.edu/etd/273

OAI identifier oai:identifier

oai:scholarscompass.vcu.edu:etd-1272