NON-RESPONSIVENESS TO PREDNISOLONE IN ALCHOL-ASSOCIATED HEPATITIS PATIENTS WAS LINKED WITH COMPROMISED HEPATIC PROTEOTOXIC STRESS RESPONSE, AND ALTERED GLUCOCORTICOID METABOLISM AND SIGNALING

Background: Alcohol-associated hepatitis (AH) is the active inflammatory state of alcohol-associated liver disease (ALD). AH varies in severity from mild to severe with mortality rates reaching 30-50% in severe AH. Prednisolone, which is a glucocorticoid receptor agonist, is the standard treatment for severe AH. The duration of treatment is based on the clinical response to prednisolone that is calculated by Lille score, where a Lille Score <0.45 at day 7 indicates that a prednisolone “responder” (AH-R) should continue treatment for 28 days. A Lille Score >0.45 indicates that a patient is a “non-responder” (AH-NR) to prednisolone and treatment should be terminated at day 7. Utilizing a proteomic approach, the current study aimed to identify hepatic proteins/pathways associated with non-responsiveness to prednisolone treatment and to characterize proteomic changes that negatively impact mortality in AH-NR.
Methods: LC/MS proteomic analysis was performed on liver biopsy samples obtained from non-ALD controls (n=10) and AH patients (n=21). Six-month survival within the AH-R was 93% (n=13 out of 14 patients) and 43% (n= 3 out of 7 patients) within the AH-NR. Significant differences in hepatic protein expression between groups were identified by a one-way ANOVA.
Results: Analysis of the hepatic proteome identified 7,944 total proteins and revealed 222 proteins that were decreased and 294 that were increased in AH-NR vs AH-R. Notably, among the significantly increased proteins in AH-NR was DHI1, an enzyme involved in metabolism of both prednisolone and prednisone. Significantly downregulated proteins in AH-NR included members of the glucocorticoid signaling pathway, GCR and GMEB2. Further, when comparing to controls, AH-R and AH-NR shared multiple protein changes but there were various proteins and pathways explicitly changed in AH-R or AH-NR. For example, the proteotoxic stress response pathway including HSF1, PSD10, RAF1, and HPBP1 was uniquely downregulated in AH-NR but not in AH-R. Next, when comparing non-survivors vs survivors within the AH-NR 113 significant proteins (57 decreased and 56 increased) were identified. Proteins involved in blood coagulation, defense response, and response to stress were significantly reduced in AH-NR non-survivors. In addition, acute inflammatory response and the expression of several acute phase proteins were downregulated in AH-NR non-survivors. For example, A1AG2, a steroid transport protein, AACT, a protease inhibitor, and AMBP, a heme homeostasis protein, among others.
Conclusion: The current study identified the specific changes in the hepatic proteins associated with non-responsiveness to prednisolone treatment and mortality in AH patients. Further studies are needed to investigate the mechanisms as to how these changes may contribute to AH patient response to prednisolone therapy and mortality.