Skip to main content
Log in

A review of the mechanisms of valproate-induced liver injury with an emphasis on the role of reactive metabolites discovered by Tom Baillie

  • Review Article
  • Published:
Medicinal Chemistry Research Aims and scope Submit manuscript

Abstract

The anticonvulsant valproic acid (VA) is associated with a range of idiosyncratic drug reactions; the most common is liver injury. The liver injury can take several forms: hyperammonemia with encephalopathy, liver injury with hepatic microvesicular steatosis, liver injury without steatosis, and a Reye’s-like syndrome. The most common form leading to liver failure is the injury with hepatic microvesicular steatosis. This is different from most drug-induced idiosyncratic liver injury. Children under the age of 2 and those with inborn errors in metabolism are at increased risk. VA is a simple branched carboxylic acid, but it is metabolized to >20 metabolites. One metabolite, 2-n-propyl-4-pentenoic acid, resembles the structure of hypoglycin A, the cause of Jamaican Vomiting Sickness. However, there does not appear to be a good correlation between the level of this metabolite and liver injury. Tom Baillie discovered that the 4-ene metabolite is further metabolized to the reactive 2,4-diene. There appears to be a correlation between the amount of the N-acetylcysteine conjugate of the 2,4-diene in the urine of patients and the risk of liver injury. There are many hypotheses as to how VA and its metabolites cause liver injury. It obviously causes mitochondrial injury, which is the basis for the microvesicular steatosis and hyperammonemia. It decreases the levels of Co-enzyme A and carnitine, but that is not sufficient to explain the liver injury. It also causes oxidative stress and changes in DNA methylation, but it is not clear what is responsible for the idiosyncratic nature of valproate-induced liver failure.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1

Similar content being viewed by others

References

  1. Coulter DL, Allen RJ. Hyperammonemia with valproic acid therapy. J Pediatr. 1981;99:317–9.

    Article  CAS  PubMed  Google Scholar 

  2. Batshaw ML, Brusilow SW. Valproate-induced hyperammonemia. Ann Neurol. 1982;11:319–21.

    Article  CAS  PubMed  Google Scholar 

  3. Kay JD, Hilton-Jones D, Hyman N. Valproate toxicity and ornithine carbamoyltransferase deficiency. Lancet. 1986;2:1283–4.

    Article  CAS  PubMed  Google Scholar 

  4. Dealberto MJ. Valproate-induced hyperammonaemic encephalopathy: review of 14 cases in the psychiatric setting. Int Clin Psychopharmacol. 2007;22:330–7.

    Article  PubMed  Google Scholar 

  5. Lheureux PE, Penaloza A, Zahir S, Gris M. Science review: carnitine in the treatment of valproic acid-induced toxicity—what is the evidence. Crit Care. 2005;9:431–40.

    Article  PubMed  PubMed Central  Google Scholar 

  6. Nakamura M, Nagamine T. The effect of carnitine supplementation on hyperammonemia and carnitine deficiency treated with valproic acid in a psychiatric setting. Innov Clin Neurosci. 2015;12:18–24.

    PubMed  PubMed Central  Google Scholar 

  7. Nicholson C, Fowler M, Mullen C, Cunningham B. Evaluation of levocarnitine, lactulose, and combination therapy for the treatment of valproic acid-induced hyperammonemia in critically ill patients. Epilepsy Res. 2021;178:106806.

    Article  CAS  PubMed  Google Scholar 

  8. Murphy JV, Groover RV, Hodge C. Hepatotoxic effects in a child receiving valproate and carnitine. J Pediatr. 1993;123:318–20.

    Article  CAS  PubMed  Google Scholar 

  9. Murphy JV, Marquardt K. Asymptomatic hyperammonemia in patients receiving valproic acid. Arch Neurol. 1982;39:591–2.

    Article  CAS  PubMed  Google Scholar 

  10. Zafrani ES, Berthelot P. Sodium valproate in the induction of unusual hepatotoxicity. Hepatology 1982;2:648–9.

    Article  CAS  PubMed  Google Scholar 

  11. Zimmerman HJ, Ishak KG. Valproate-induced hepatic injury: analyses of 23 fatal cases. Hepatology 1982;2:591–7.

    Article  CAS  PubMed  Google Scholar 

  12. Powell-Jackson PR, Tredger JM, Williams R. Hepatotoxicity to sodium valproate: a review. Gut 1984;25:673–81.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  13. König SA, Siemes H, Bläker F, et al. Severe hepatotoxicity during valproate therapy: an update and report of eight new fatalities. Epilepsia 1994;35:1005–15.

    Article  PubMed  Google Scholar 

  14. Zimmerman H. Hepatotoxicity: The adverse effects of drugs and other chemicals on the liver. Philadelphia: Lippincott Williams & Wilkins; 1999.

  15. Gerber N, Dickinson RG, Harland RC, et al. Reye-like syndrome associated with valproic acid therapy. J Pediatr. 1979;95:142–4.

    Article  CAS  PubMed  Google Scholar 

  16. Young RS, Bergman I, Gang DL, Richardson EP. Fatal Reye-like syndrome associated with valproic acid. Ann Neurol. 1980;7:389.

    Article  CAS  PubMed  Google Scholar 

  17. Chalasani N, Bonkovsky HL, Stine JG, et al. Clinical characteristics of antiepileptic-induced liver injury in patients from the DILIN prospective study. J Hepatol. 2022;76:832–40.

    Article  CAS  PubMed  Google Scholar 

  18. Finsterer J, Zarrouk Mahjoub S. Epilepsy in mitochondrial disorders. Seizure. 2012;21:316–21.

    Article  PubMed  Google Scholar 

  19. Stewart JD, Horvath R, Baruffini E, et al. Polymerase gamma gene POLG determines the risk of sodium valproate-induced liver toxicity. Hepatology 2010;52:1791–6.

    Article  CAS  PubMed  Google Scholar 

  20. Hynynen J, Pokka T, Komulainen-Ebrahim J, et al. Variants p.Q1236H and p.E1143G in mitochondrial DNA polymerase gamma POLG1 are not associated with increased risk for valproate-induced hepatotoxicity or pancreatic toxicity: A retrospective cohort study of patients with epilepsy. Epilepsia. 2018;59:2125–36.

    Article  CAS  PubMed  Google Scholar 

  21. Li J, Norwood DL, Mao LF, Schulz H. Mitochondrial metabolism of valproic acid. Biochemistry. 1991;30:388–94.

    Article  CAS  PubMed  Google Scholar 

  22. Ponchaut S, van Hoof F, Veitch K. In vitro effects of valproate and valproate metabolites on mitochondrial oxidations. Relevance of CoA sequestration to the observed inhibitions. Biochem Pharm. 1992;43:2435–42.

    Article  CAS  PubMed  Google Scholar 

  23. Price KE, Pearce RE, Garg UC, et al. Effects of valproic acid on organic acid metabolism in children: a metabolic profiling study. Clin Pharm Ther. 2011;89:867–74.

    Article  CAS  Google Scholar 

  24. Verrotti A, Agostinelli S, Parisi P, Chiarelli F, Coppola G. Nonalcoholic fatty liver disease in adolescents receiving valproic acid. Epilepsy Behav. 2011;20:382–5.

    Article  PubMed  Google Scholar 

  25. Tong V, Teng XW, Chang TK, Abbott FSVA. I: time course of lipid peroxidation biomarkers, liver toxicity, and valproic acid metabolite levels in rats. Toxicol Sci. 2005;86:427–35.

    Article  CAS  PubMed  Google Scholar 

  26. Michoulas A, Tong V, Teng XW, Chang TK, Abbott FS, Farrell K. Oxidative stress in children receiving valproic acid. J Pediatr. 2006;149:692–6.

    Article  CAS  PubMed  Google Scholar 

  27. Gai Z, Krajnc E, Samodelov SL, Visentin M, Kullak-Ublick GA. Obeticholic acid ameliorates valproic acid-induced hepatic steatosis and oxidative stress. Mol Pharm. 2020;97:314–23.

    Article  CAS  Google Scholar 

  28. Ahmed N, Aljuhani N, Al-Hujaili HS, et al. Agmatine protects against sodium valproate-induced hepatic injury in mice via modulation of nuclear factor-κB/inducible nitric oxide synthetase pathway. J Biochem Mol Toxicol. 2018;32:e22227.

    Article  PubMed  Google Scholar 

  29. Wolters JEJ, van Breda SGJ, Caiment F, Claessen SM, de Kok TMCM, Kleinjans JCS. Nuclear and mitochondrial DNA methylation patterns induced by valproic acid in human hepatocytes. Chem Res Toxicol. 2017;30:1847–54.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Ezhilarasan D, Mani U. Valproic acid induced liver injury: An insight into molecular toxicological mechanism. Environ Toxicol Pharm. 2022;95:103967.

    Article  CAS  Google Scholar 

  31. Rettenmeier AW, Gordon WP, Prickett KS, et al. Metabolic fate of valproic acid in the rhesus monkey. Formation of a toxic metabolite, 2-n-propyl-4-pentenoic acid. Drug Metab Dispos. 1986;14:443–53.

    CAS  PubMed  Google Scholar 

  32. Rettenmeier AW, Howald WN, Levy RH, et al. Quantitative metabolic profiling of valproic acid in humans using automated gas chromatographic/mass spectrometric techniques. Biomed Environ Mass Spectrom. 1989;18:192–9.

    Article  CAS  PubMed  Google Scholar 

  33. Bjorge SM, Baillie TA. Studies on the beta-oxidation of valproic acid in rat liver mitochondrial preparations. Drug Metab Dispos. 1991;19:823–9.

    CAS  PubMed  Google Scholar 

  34. Tanaka K, Kean EA, Johnson B. Jamaican vomiting sickness. Biochemical investigation of two cases. N Engl J Med. 1976;295:461–7.

    Article  CAS  PubMed  Google Scholar 

  35. Kochen W, Schneider A, Ritz A. Abnormal metabolism of valproic acid in fatal hepatic failure. Eur J Pediatr. 1983;141:30–35.

    Article  CAS  PubMed  Google Scholar 

  36. Rettie AE, Boberg M, Rettenmeier AW, Baillie TA. Cytochrome P-450-catalyzed desaturation of valproic acid in vitro. Species differences, induction effects, and mechanistic studies. J Biol Chem. 1988;263:13733–8.

    Article  CAS  PubMed  Google Scholar 

  37. Rettie AE, Rettenmeier AW, Howald WN, Baillie TA. Cytochrome P-450-catalyzed formation of delta 4-VPA, a toxic metabolite of valproic acid. Science. 1987;235:890–3.

    Article  CAS  PubMed  Google Scholar 

  38. Sadeque AJ, Fisher MB, Korzekwa KR, Gonzalez FJ, Rettie AE. Human CYP2C9 and CYP2A6 mediate formation of the hepatotoxin 4-ene-valproic acid. J Pharm Exp Ther. 1997;283:698–703.

    CAS  Google Scholar 

  39. Rettie AE, Sheffels PR, Korzekwa KR, Gonzalez FJ, Philpot RM, Baillie TA. CYP4 isozyme specificity and the relationship between omega-hydroxylation and terminal desaturation of valproic acid. Biochemistry. 1995;34:7889–95.

    Article  CAS  PubMed  Google Scholar 

  40. Levy RH, Rettenmeier AW, Anderson GD, et al. Effects of polytherapy with phenytoin, carbamazepine, and stiripentol on formation of 4-ene-valproate, a hepatotoxic metabolite of VA. Clin Pharm Ther. 1990;48:225–35.

    Article  CAS  Google Scholar 

  41. Bjorge SM, Baillie TA. Inhibition of medium-chain fatty acid beta-oxidation in vitro by valproic acid and its unsaturated metabolite, 2-n-propyl-4-pentenoic acid. Biochem Biophys Res Commun. 1985;132:245–52.

    Article  CAS  PubMed  Google Scholar 

  42. Kesterson JW, Granneman GR, Machinist JM. The hepatotoxicity of valproic acid and its metabolites in rats. I. Toxicologic, biochemical and histopathologic studies. Hepatology. 1984;4:1143–52.

    Article  CAS  PubMed  Google Scholar 

  43. Lewis JH, Zimmerman HJ, Garrett CT, Rosenberg E. Valproate-induced hepatic steatogenesis in rats. Hepatology. 1982;2:870–3.

    Article  CAS  PubMed  Google Scholar 

  44. Espandiari P, Zhang J, Schnackenberg LK, et al. Age-related differences in susceptibility to toxic effects of valproic acid in rats. J Appl Toxicol. 2008;28:628–37.

    Article  CAS  PubMed  Google Scholar 

  45. Siemes H, Nau H, Schultze K, et al. Valproate (VPA) metabolites in various clinical conditions of probable VPA-associated hepatotoxicity. Epilepsia. 1993;34:332–46.

    Article  CAS  PubMed  Google Scholar 

  46. Tennison MB, Miles MV, Pollack GM, Thorn MD, Dupuis RE. Valproate metabolites and hepatotoxicity in an epileptic population. Epilepsia. 1988;29:543–7.

    Article  CAS  PubMed  Google Scholar 

  47. Rettenmeier AW, Gordon WP, Prickett KS, Levy RH, Baillie TA. Biotransformation and pharmacokinetics in the rhesus monkey of 2-n-propyl-4-pentenoic acid, a toxic metabolite of valproic acid. Drug Metab Dispos. 1986;14:454–64.

    CAS  PubMed  Google Scholar 

  48. Kassahun K, Hu P, Grillo MP, Davis MR, Jin L, Baillie TA. Metabolic activation of unsaturated derivatives of valproic acid. Identification of novel glutathione adducts formed through coenzyme A-dependent and -independent processes. Chem Biol Interact. 1994;90:253–75.

    Article  CAS  PubMed  Google Scholar 

  49. Porubek DJ, Grillo MP, Baillie TA. The covalent binding to protein of valproic acid and its hepatotoxic metabolite, 2-n-propyl-4-pentenoic acid, in rats and in isolated rat hepatocytes. Drug Metab Dispos. 1989;17:123–30.

    CAS  PubMed  Google Scholar 

  50. Prickett KS, Baillie TA. Metabolism of unsaturated derivatives of valproic acid in rat liver microsomes and destruction of cytochrome P-450. Drug Metab Dispos. 1986;14:221–9.

    CAS  PubMed  Google Scholar 

  51. Kassahun K, Baillie TA. Cytochrome P-450-mediated dehydrogenation of 2-n-propyl-2(E)-pentenoic acid, a pharmacologically-active metabolite of VA, in rat liver microsomal preparations. Drug Metab Dispos. 1993;21:242–8.

    CAS  PubMed  Google Scholar 

  52. Kassahun K, Farrell K, Abbott F. Identification and characterization of the glutathione and N-acetylcysteine conjugates of (E)-2-propyl-2,4-pentadienoic acid, a toxic metabolite of valproic acid, in rats and humans. Drug Metab Dispos. 1991;19:525–35.

    CAS  PubMed  Google Scholar 

  53. Gopaul S, Farrell K, Abbott F. Effects of age and polytherapy, risk factors of VALPROIC ACID (VPA) hepatotoxicity, on the excretion of thiol conjugates of (E)-2,4-diene VPA in people with epilepsy taking VPA. Epilepsia. 2003;44:322–8.

    Article  CAS  PubMed  Google Scholar 

  54. Dreifuss FE, Santilli N, Langer DH, Sweeney KP, Moline KA, Menander KB. VALPROIC ACID hepatic fatalities: a retrospective review. Neurology 1987;37:379–85.

    Article  CAS  PubMed  Google Scholar 

  55. Cho T, Uetrecht J. How Reactive Metabolites Induce an Immune Response That Sometimes Leads to an Idiosyncratic Drug Reaction. Chem Res Toxicol. 2017;30:295–314.

    Article  CAS  PubMed  Google Scholar 

  56. van Zoelen MA, de Graaf M, van Dijk MR, et al. valproic acid-induced DRESS syndrome with acute liver failure. Neth J Med. 2012;70:155.

    PubMed  Google Scholar 

  57. Gigli GL, Scalise A, Pauri F, et al. Valproate-induced systemic lupus erythematosus in a patient with partial trisomy of chromosome 9 and epilepsy. Epilepsia 1996;37:587–8.

    Article  CAS  PubMed  Google Scholar 

  58. Park-Matsumoto YC, Tazawa T. Valproate induced lupus-like syndrome. J Neurol Sci. 1996;143:185–6.

    Article  CAS  PubMed  Google Scholar 

  59. Verrotti A, Basciani F, Trotta D, Greco R, Morgese G, Chiarelli F. Effect of anticonvulsant drugs on interleukins-1, -2 and -6 and monocyte chemoattractant protein-1. Clin Exp Med. 2001;1:133–6.

    Article  CAS  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Jack Uetrecht.

Ethics declarations

Conflict of interest

The author declares no competing interests.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Uetrecht, J. A review of the mechanisms of valproate-induced liver injury with an emphasis on the role of reactive metabolites discovered by Tom Baillie. Med Chem Res 32, 1995–2000 (2023). https://doi.org/10.1007/s00044-023-03130-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00044-023-03130-x

Keywords

Navigation