Oxidative Albumin Damage in Chronic Liver Failure: Relation to Albumin Binding Capacity, Liver Dysfunction and Survival
Bibliographic info
- Authors: Karl Oettl, Ruth Birner-Gruenberger, Walter Spindelboeck, Hans Peter Stueger, Livia Dorn, Vanessa Stadlbauer, Csilla Putz-Bankuti, Peter Krisper, Ivo Graziadei, Wolfgang Vogel, Carolin Lackner, Rudolf E. Stauber
- Journal: Journal of Hepatology, 2013, with accompanying Editorial pp. 918–920
- Institutions: Medical University of Graz; Medical University of Innsbruck, Austria
Key question
Does irreversibly oxidized albumin (HNA2) relate to albumin binding function and does it predict 30-day and 90-day survival in patients with advanced liver disease and sepsis?
Methods
- Sample type: Plasma from cirrhotic patients and septic patients
- Technique: HPLC-ESI-MS (top-down) for HMA/HNA1/HNA2 quantification; Orbitrap Velos LC-MS/MS (Thermo) for BU confirmation of sulfonic acid at Cys residues; dansylsarcosine (DS) binding assay for albumin binding site II capacity
- Cohort: Cirrhotic patients (n specified for DS binding subset n=29) + septic patients (n=18); external validation cohort for survival
- Statistical: Spearman correlation; stepwise regression; ROC analysis (AUROCs); Kaplan-Meier; Youden index for cut-off
Key definitions: HMA / HNA1 / HNA2 nomenclature
| Form | Cys34 state | Δmass | Fraction (healthy) |
|---|---|---|---|
| HMA (mercaptalbumin) | Free thiol (reduced) | 0 | 70–80% |
| HNA1 (nonmercaptalbumin-1) | Reversibly oxidized (disulfide with Cys/homocysteine/glutathione) | +119 Da (cysteinylation) | 20–30% |
| HNA2 (nonmercaptalbumin-2) | Irreversibly oxidized (sulfinic/sulfonic acid at Cys34) | +32 Da / +48 Da | ~5% |
Main findings
- HNA2 (irreversible oxidation) is significantly elevated in patients with advanced cirrhosis compared to healthy subjects — 4-fold increase, the highest values reported among all patient groups at that time
- HNA2 correlates with MELD score, bilirubin, INR, and CRP — reflecting both liver dysfunction and systemic inflammation as drivers of irreversible oxidation
- Albumin binding capacity impaired: DS binding (binding site II, benzodiazepine site) reduced in both cirrhotic and septic patients
- DS binding better explained by bilirubin and INR than by HNA2 in stepwise regression — suggests competitive displacement at site II is driven more by ligand accumulation than by Cys34 oxidation per se
- HNA2 predicts 30-day and 90-day survival in cirrhotic patients — optimal cut-off: 12% HNA2
- Patients with baseline HNA2 >12% had significantly higher 90-day mortality (Kaplan-Meier)
- AUROCs for HNA2 vs MELD: comparable (not significantly different)
- External validation cohort: survival prediction confirmed
- Sepsis comparison: HNA2 also elevated in septic patients without liver disease → HNA2 reflects systemic oxidative stress broadly, not only liver disease
Clinical context
- Disease: Advanced Liver fibrosis / cirrhosis; sepsis
- Biomarker: HNA2 >12% = poor prognosis (30/90-day survival)
- Implication: Irreversible oxidation of Cys34 on HSA is a marker of cumulative systemic oxidative burden; once irreversible (HNA2), no functional recovery possible — unlike HNA1 (reversible)
Limitations
- Sample size for binding studies small (n=29 for DS; n=18 sepsis)
- HNA2 and MELD had comparable AUROCs — HNA2 does not outperform MELD alone in this cohort
- IEC/HPLC method used — not the more modern full isoform LC-HR-MS approach of the Bologna group; only quantifies Cys34 redox states (HMA/HNA1/HNA2), not the full multiPTM isoform landscape
Connections
- HSA — Cys34 redox state focus (HMA/HNA1/HNA2)
- Oxidation — HNA2 as marker of irreversible oxidative damage
- Liver fibrosis — cirrhosis severity correlation
- domenicali-2014 — complements with full isoform profiling (7 isoforms) vs Cys34-only approach here
- baldassarre-2021-ealb — effective albumin concept directly builds on this; eAlb = fraction of structurally intact albumin including Cys34 state
- alcaraz-quiles-2018 — HNA1 (reversible oxidation) triggers p38 MAPK cytokine storm; HNA2 levels from this paper used as comparison
Take home notes
- This paper establishes the cut-off HNA2 >12% = poor 30/90-day prognosis — a clinically actionable threshold that should be tracked in the ALBOM context.
- The Graz group (Oettl, Stauber) is the main Austrian center for albumin redox biology; they developed the IEC-based HMA/HNA1/HNA2 quantification method used widely in this field.
- Critical distinction from the Bologna group’s approach: Oettl et al. only resolve Cys34 redox states (3 fractions). The HPLC-MS approach of domenicali-2014 and el-balkhi-2025 resolves all multi-PTM isoform combinations (7→10 isoforms). More information content in the isoform approach.
- HNA2 in the ALBOM context corresponds to what Soli calls the “sulfonylated” isoform (HSA+SULF, +48 Da). Its increase in severe CLD is consistent with this paper’s findings.