ritonavir and Chemical-and-Drug-Induced-Liver-Injury--Chronic

Ritonavir (RTV), a pharmacoenhancer used in anti-HIV regimens, can induce liver damage. RTV is primarily metabolized by cytochrome P450 3A4 (CYP3A4) in the liver. HNF4A antisense RNA 1 (HNF4A-AS1) and HNF1A antisense RNA 1 (HNF1A-AS1) are long noncoding RNAs that regulate the expression of pregnane X receptor (PXR) and CYP3A4. This study investigated the role and underlying mechanisms of HNF4A-AS1 and HNF1A-AS1 in RTV-induced hepatotoxicity. HNF4A-AS1 and HNF1A-AS1 were knocked down by small hairpin RNAs in Huh7 and HepG2 cells. Lactate dehydrogenase and reactive oxygen species assays were performed to assess RTV-induced hepatotoxicity. Chromatin immunoprecipitation quantitative real-time polymerase chain reaction was used to detect PXR enrichment and histone modifications in the CYP3A4 promoter. HNF4A-AS1 knockdown increased PXR and CYP3A4 expression and exacerbated RTV-induced cytotoxicity, whereas HNF1A-AS1 knockdown generated the opposite phenotype. Mechanistically, enrichment of PXR and trimethylation of histone 3 lysine 4 (H3K4me3) in the CYP3A4 promoter was increased, and trimethylation of histone 3 lysine 27 (H3K27me3) was decreased after HNF4A-AS1 knockdown. However, PXR and H3K4me3 enrichment decreased after HNF1A-AS1 knockdown. Alterations in RTV-induced hepatotoxicity caused by decreasing HNF4A-AS1 or HNF1A-AS1 were reversed by knockdown or overexpression of PXR. Increased susceptibility to RTV-induced liver injury caused by the PXR activator rifampicin was attenuated by HNF4A-AS1 overexpression or HNF1A-AS1 knockdown. Taken together, these results revealed that HNF4A-AS1 and HNF1A-AS1 modulated RTV-induced hepatotoxicity by regulating CYP3A4 expression, primarily by affecting the binding of PXR and histone modification status in the CYP3A4 promoter. SIGNIFICANCE STATEMENT: HNF4A-AS1 and HNF1A-AS1, transcribed separately from neighboring antisense genes of the human transcription factor genes

Topics: Carcinoma, Hepatocellular; Chemical and Drug Induced Liver Injury, Chronic; Cytochrome P-450 CYP3A; Hepatocyte Nuclear Factor 1; Hepatocyte Nuclear Factor 4; Histones; Humans; Liver Neoplasms; Lysine; Receptors, Steroid; Rifampin; Ritonavir; RNA, Antisense; RNA, Long Noncoding

To evaluate the occurrence of hepatotoxicity in patients during antiretroviral therapy (ART) that contains protease inhibitors and the role of hepatitis viruses in its development, we performed a retrospective study including 1325 HIV-infected patients treated with ART for at least 6 months. Presence or absence of hepatitis viruses, alanine aminotransferase (ALT), total bilirubin, CD4 cell count, and plasma HIV RNA levels were evaluated. Hepatotoxicity developed in a few study subjects without coinfection, whereas it was significantly higher in coinfected patients. Univariate logistic regression analysis showed that viral hepatitis coinfections are independent risk factors for hepatotoxicity. After 6 months of treatment, ritonavir was associated with higher rates of severe hepatotoxicity in the coinfected group; in fact, ritonavir seems to be the most strongly hepatotoxic agent among coinfected patients. After 12 months of therapy, hepatotoxicity occurred more frequently in patients with hepatitis C virus who did not respond to antiretroviral therapy (ART), whereas patients who did respond to ART showed decreased ALT levels. Hepatotoxicity is not exclusively an effect of drug toxicity, and the presence of hepatitis coinfection is an independent risk factor. Moreover, chronic hepatotoxicity mainly occurs in patients who did not respond to therapy. Conversely, patients who did respond to ART seemed to show improvement of chronic liver infection.

Topics: Adult; Alanine Transaminase; Antiviral Agents; Bilirubin; Chemical and Drug Induced Liver Injury, Chronic; Female; Hepatitis B; Hepatitis C; HIV Infections; HIV Protease Inhibitors; Humans; Italy; Male; Prevalence; Regression Analysis; Retrospective Studies; Risk Factors; Ritonavir; Time Factors; Viral Load