Ritonavir and Lopinavir Suppress RCE1 and CAAX Rab Proteins Sensitizing the Liver to Organelle Stress and Injury

Abstract

Organelle stress and Liver injuries often occur in human immunodeficiency virus (HIV) infected patients underanti-HIV therapies, yet few molecular off-targets of anti-HIV drugs have been identified in the liver. Here, we found through total RNA sequencing that the transcription of a host protease Ras converting CAAX endopeptidase 1 (RCE1) was altered in HepG2 cells treated with anti-HIV protease inhibitors, ritonavir and lopinavir. Levels of RCE1 protein were inhibited in HepG2 and primary mouse hepatocytes and in the liver of mice treated with the anti-HIV drugs, which were accompanied with inhibition of two potential substrates of RCE1, small GTP binding protein Rab13 and Rab18, which are with a common CAAX motif and known to regulate the ER-Golgi traffic or lipogenesis. Neither Rce1 transcription nor RCE1 protein level was inhibited by Brefeldin A, which is known to interfere with the ER-Golgi traffic causing Golgi stress. Knocking down Rce1 with RNA interference increased ritonavir and lopinavir-induced cell death as well as expression of Golgi stress response markers, TFE3, HSP47 and GCP60, in both primary mouse hepatocytes and mouse liver, and deteriorated alcohol-induced alanine aminotransferase (ALT) and fatty liver injury in mice. In addition, overexpressing Rab13 or Rab18 in primary human hepatocytes reduced partially the anti-HIV drugs and alcohol-induced Golgi fragmentation, Golgi stress response, and cell death injury. Conclusion: We identified a mechanism linking a host protease and its substrates, small guanosine triphosphate-binding proteins, to the anti-HIV drug-induced Golgi dysfunction, organelle stress response, and fatty liver injury. (Hepatology Communications 2020;4:932-944).

Drug-Induced Liver Injury in COVID-19 Patients: A Systematic Review

“…In a more recent study evaluating the biliary excretion index (BEI) of 5( 6 )-carboxy-29, 79 dichlorofluorescein (CDF) through confocal imaging, the inhibitory effects of LPV was further supported ( 88 ). In another recent study, hepatotoxicity of PIs, LPV and, RTV, was reported to interfere with ER-Golgi trafficking via inhibition of Ras converting CAAX endopeptidase-1 (RCE1) and its potential substrates, leading to cellular stress responses and fatty liver disease ( 89 ). Another possible cause of hepatotoxicity due to LPV/RTV is insufficient P450 activity to metabolize large amounts of those drugs during the treatment period.…”

Adverse Effects of Anti‐Covid‐19 Drug Candidates and Alcohol on Cellular Stress Responses of Hepatocytes

“…Extraction of proteins from the whole-cell lysates, immunohistochemistry, and fluorescence immunohistochemistry were conducted according to the method described previously. (21,22)…”

Past and Future Strategies to Inhibit Membrane Localization of the KRAS Oncogene

“…Another screening approach identified nine small-molecule inhibitors of RCE1, including NSC 1011, 73101, 295642, 321237, and 609974 [41]. Recently, it has been published that the anti-HIV protease inhibitors Ritonavir and Lopinavir can suppress RCE1 and CAAX Rab proteins, sensitizing the liver to organelle stress and injury [42].…”