Pidotimod increases inflammation in wounded zebrafish embryos

Li Ding; Kaiming Luo; Carl G Feng; Stefan H Oehlers

doi:10.1016/j.fsi.2021.12.013

Pidotimod increases inflammation in wounded zebrafish embryos

Fish Shellfish Immunol. 2022 Jan:120:429-433. doi: 10.1016/j.fsi.2021.12.013. Epub 2021 Dec 16.

Authors

Li Ding¹, Kaiming Luo², Carl G Feng³, Stefan H Oehlers⁴

Affiliations

¹ Department of Infectious Diseases, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China; School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, NSW, 20006, Australia; Tuberculosis Research Program at the Centenary Institute, The University of Sydney, Camperdown, NSW, 2050, Australia. Electronic address: dingli@mail.sysu.edu.cn.
² Tuberculosis Research Program at the Centenary Institute, The University of Sydney, Camperdown, NSW, 2050, Australia. Electronic address: op21425@bristol.ac.uk.
³ School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, NSW, 20006, Australia; Tuberculosis Research Program at the Centenary Institute, The University of Sydney, Camperdown, NSW, 2050, Australia. Electronic address: carl.feng@sydney.edu.au.
⁴ School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, NSW, 20006, Australia; Tuberculosis Research Program at the Centenary Institute, The University of Sydney, Camperdown, NSW, 2050, Australia. Electronic address: s.oehlers@centenary.org.au.

PMID: 34922016
DOI: 10.1016/j.fsi.2021.12.013

Abstract

Pidotimod (PDT) is a synthetic dipeptide molecule which can improve immune responses in mice and humans, protecting hosts from infection. However, the exact mechanism of protection remains ill-defined. The effect of pidotimod has not yet been investigated in the inflammatory response of zebrafish. In this study, we used tail wound and infection models of zebrafish to study the effect of PDT on inflammation. We found that zebrafish larvae were sensitive to PDT immersion causing toxicity at doses above 50 μg/mL. The tail wound assay showed that PDT increased the recruitment of neutrophils and macrophages to the wound site and promoted the transcription of the pro-inflammatory cytokine il1b. However, we did not observe protection of uropathogenic Escherichia coli or Mycobacterium marinum infected zebrafish larvae following PDT treatment. This study provides a new platform for PDT research, which is worthy of further research to identify further effects of PDT therapy.

Keywords: Inflammation; Pidotimod; Tail wound; Toxicity; Zebrafish.

MeSH terms

Animals
Inflammation* / chemically induced
Larva
Pyrrolidonecarboxylic Acid / adverse effects
Pyrrolidonecarboxylic Acid / analogs & derivatives*
Thiazolidines / adverse effects*
Zebrafish*

Substances

Thiazolidines
pidotimod
Pyrrolidonecarboxylic Acid