Rifampicin-induced ER stress and excessive cytoplasmic vacuolization instigate hepatotoxicity via alternate programmed cell death paraptosis in vitro and in vivo.

Abstract

AIMS:

Rifampicin-induced hepatotoxicity is a primary cause of drug-induced liver injury (DILI), posing a significant challenge to its continued clinical application. Moreover, the mechanism underlying rifampicin-induced hepatotoxicity remains unclear.

MAIN METHODS:

Human hepatocyte line-17 (HHL-17) cells were treated with an increasing dose of rifampicin for 24 h, and male Wistar rats were given rifampicin [150 mg/kg body weight (bw)] orally for 28 days. Viability assay, protein expression, and cell death assays were analyzed in vitro. Moreover, liver serum markers, body/organ weight, H&E staining, protein expression, etc., were assayed in vivo.

KEY FINDINGS:

Rifampicin induced a dose-dependent hepatotoxicity in HHL-17 cells (IC50; 600 μM), and increased the serum levels of liver injury markers, e.g., alanine transaminase (ALT) and aspartate transaminase (AST) in rats. Rifampicin-induced cell death was non-apoptotic and non-necroptotic both in vitro and in vivo. Further, excessive cellular vacuolization and reduced expression of Alix protein confirmed the induction of paraptosis both in vitro and in vivo. In addition, a significant increase in the endoplasmic reticulum (ER) stress markers (e.g., BiP, CHOP, and total polyubiquitinated proteins) was detected, demonstrating the induction of ER stress and altered protein homeostasis. Interestingly, rifampicin-induced hepatotoxicity was associated with the inhibition of autophagy and enhanced reactive oxygen species (ROS) generation in HHL-17 cells. Furthermore, inhibition of protein synthesis by cycloheximide (CHX) suppressed paraptosis by alleviating rifampicin-induced ER stress and ROS generation.

SIGNIFICANCE:

Rifampicin-induced hepatotoxicity involves ER stress-driven paraptosis as a novel mechanism of its toxicity that may be targeted to protect liver cells from rifampicin toxicity.

• Authors: K M Kainat, Mohammad Imran Ansari, Nuzhat Bano, Pankaj Ramji Jagdale, Anjaneya Ayanur, Mahadeo Kumar, Pradeep Kumar Sharma
• Journal: Life sciences (Life Sci) Vol. 333 Pg. 122164 (Nov 15 2023) ISSN: 1879-0631 [Electronic] Netherlands
• PMID: 37827230 (Publication Type: Journal Article)
• Copyright: Copyright © 2023 Elsevier Inc. All rights reserved.

Chemical References

• Rifampin
• Reactive Oxygen Species

Topics

• Male
• Humans
• Rats
• Animals
• Rifampin (toxicity)
• Reactive Oxygen Species (metabolism)
• Rats, Wistar
• Apoptosis
• Endoplasmic Reticulum Stress
• Chemical and Drug Induced Liver Injury (etiology)