eCite Digital Repository

Pro-inflammatory and pro-apoptotic effects of the non-protein amino acid L-Azetidine-2-carboxylic acid in BV2 microglial cells


Piper, JA and Jansen, MI and Broome, ST and Rodgers, KJ and Musumeci, G and Castorina, A, Pro-inflammatory and pro-apoptotic effects of the non-protein amino acid L-Azetidine-2-carboxylic acid in BV2 microglial cells, Current Issues in Molecular Biology, 44, (10) pp. 4500-4516. ISSN 1467-3045 (2022) [Refereed Article]

PDF (Published)

Copyright Statement

2022. The Authors. Licensee MDPI, Basel, Switzerland. This article is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) License (, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

DOI: doi:10.3390/cimb44100308


L-Azetidine-2-carboxylic acid (AZE) is a toxic non-protein coding amino acid (npAA) that is highly abundant in sugar and table beets. Due to its structural similarity with the amino acid L-proline, AZE can evade the editing process during protein assembly in eukaryotic cells and be misincorporated into L-proline-rich proteins, potentially causing protein misfolding and other detrimental effects to cells. In this study, we sought to determine if AZE treatment triggered pro-inflammatory and pro-apoptotic responses in BV2 microglial cells. BV2 microglial cells exposed to AZE at increasing concentrations (02000 M) at 0, 3, 6, 12 and 24 h were assayed for cell viability (MTT) and nitric oxide release (Griess assay). Annexin V-FITC/propidium iodide (PI) staining was used to assess apoptosis. Real-time qPCR, Western blot and immunocytochemistry were used to interrogate relevant pro- and anti-inflammatory and other molecular targets of cell survival response. AZE (at concentrations > 1000 M) significantly reduced cell viability, increased BAX/Bcl2 ratio and caused cell death. Results were mirrored by a robust increase in nitric oxide release, percentage of activated/polarised cells and expression of pro-inflammatory markers (IL-1β, IL-6, NOS2, CD68 and MHC-2a). Additionally, we found that AZE induced the expression of the extracellular matrix degrading enzyme matrix metalloproteinase 9 (MMP-9) and brain derived neurotrophic factor (BDNF), two critical regulators of microglial motility and structural plasticity. Collectively, these data indicate that AZE-induced toxicity is associated with increased pro-inflammatory activity and reduced survival in BV2 microglia. This evidence may prompt for an increased monitoring of AZE consumption by humans.

Item Details

Item Type:Refereed Article
Keywords:azetidine, proinflammatory, neuropathology, neuroscience,
Research Division:Biomedical and Clinical Sciences
Research Group:Neurosciences
Research Field:Central nervous system
Objective Division:Health
Objective Group:Clinical health
Objective Field:Diagnosis of human diseases and conditions
UTAS Author:Piper, JA (Mr Jordan Piper)
ID Code:153963
Year Published:2022
Deposited By:Health Sciences
Deposited On:2022-10-18
Last Modified:2022-12-11
Downloads:1 View Download Statistics

Repository Staff Only: item control page