Arginase as a Potential Biomarker of Disease Progression: A Molecular Imaging Perspective

Gonçalo Santos Clemente, dos, Aren van Waarde, Ines F. Antunes, Alex Dömling, Philip H. Elsinga*

*Corresponding author for this work

Research output: Contribution to journalReview articlepeer-review

38 Citations (Scopus)
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Arginase is a widely known enzyme of the urea cycle that catalyzes the hydrolysis of L-arginine to L-ornithine and urea. The action of arginase goes beyond the boundaries of hepatic ureogenic function, being widespread through most tissues. Two arginase isoforms coexist, the type I (Arg1) predominantly expressed in the liver and the type II (Arg2) expressed throughout extrahepatic tissues. By producing L-ornithine while competing with nitric oxide synthase (NOS) for the same substrate (L-arginine), arginase can influence the endogenous levels of polyamines, proline, and NO•. Several pathophysiological processes may deregulate arginase/NOS balance, disturbing the homeostasis and functionality of the organism. Upregulated arginase expression is associated with several pathological processes that can range from cardiovascular, immune-mediated, and tumorigenic conditions to neurodegenerative disorders. Thus, arginase is a potential biomarker of disease progression and severity and has recently been the subject of research studies regarding the therapeutic efficacy of arginase inhibitors. This review gives a comprehensive overview of the pathophysiological role of arginase and the current state of development of arginase inhibitors, discussing the potential of arginase as a molecular imaging biomarker and stimulating the development of novel specific and high-affinity arginase imaging probes.
Original languageEnglish
Article number5291
Pages (from-to)1-36
Number of pages36
JournalInternational Journal of Molecular Sciences
Issue number15
Publication statusPublished - 25-Jul-2020


  • arginase
  • nitric oxide
  • arginase inhibitors
  • molecular imaging
  • positron emission tomography (PET)

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