ORCID Profile
0000-0003-3368-6937
Current Organisation
University of South Australia
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Publisher: Wiley
Date: 22-02-2023
DOI: 10.1111/IJFS.16341
Abstract: In this study, sea cucumber ( Holothuria scabra Jaegar 1833) extracts and collagens were evaluated for inhibitory properties of protein‐bound advanced glycation end products (AGEs). Processed dried sea cucumber with salt extract showed a significant lower IC 50 value for fluorescent AGEs (9.19 ± 7.68 μg mL −1 , P 0.05) and fructosamine (503.47 ± 46.37 μg mL −1 , P 0.05), respectively. Processed dried with and without salt extracts significantly reduced the N ε ‐carboxymethyllysine (CML) and methylglyoxal‐derived hydroimidazolone‐1 (MG‐H1) levels tested at 250 μg mL −1 . Smoked dried and fresh‐dried extracts significantly reduced the N ε ‐carboxyethyllysine (CEL) levels tested at 250 μg mL −1 . Pepsin‐solubilised collagen and the crude collagen fibrils significantly reduced CML and MG‐H1 levels whereas CEL levels were unchanged. Pearson's correlation analysis showed that protein‐bound AGE and CML inhibition significantly correlated with the total phenolic and antioxidant activities, respectively. This study provides a strong rationale for further investigation aimed at identifying the active compounds responsible for the observed effects on biomarkers relevant to diabetes.
Publisher: Elsevier BV
Date: 05-2023
Publisher: Elsevier
Date: 2023
Publisher: Oxford University Press (OUP)
Date: 06-10-2021
Abstract: Advanced glycation end products (AGEs) are formed via non-enzymatic reactions between amino groups of proteins and the carbonyl groups of reducing sugars. Previous studies have shown that highly glycated albumin prepared using a glucose-bovine serum albumin (Glu-BSA) model system incubated at 60°C for 6 weeks induces genotoxicity in WIL2-NS cells at 9 days of exposure measured by the cytokinesis-block micronucleus cytome (CBMNcyt) assay. However, this AGE model system is not physiologically relevant as normal body temperature is 37°C and the degree of glycation may exceed the extent of albumin modification in vivo. We hypothesised that the incubation temperature and purification method used in these studies may cause changes to the chemical profile of the glycated albumin and may influence the extent of genotoxicity observed at 3, 6 and 9 days of exposure. We prepared AGEs generated using Glu-BSA model systems incubated at 60°C or 37°C purified using trichloroacetic acid (TCA) precipitation or ultrafiltration (UF) and compared their chemical profile (glycation, oxidation, and aggregation) and genotoxicity in WIL2-NS cells using the CBMNcyt assay after 3, 6 and 9 days of exposure. The number of micronuclei (MNi) was significantly higher for cells treated with Glu-BSA incubated at 60°C and purified via TCA (12 ± 1 MNi/1000 binucleated cells) compared to Glu-BSA incubated at 37°C and purified using UF (6 ± 1 MNi/1000 binucleated cells) after 9 days (P & 0.0001). The increase in genotoxicity observed could be explained by a higher level of protein glycation, oxidation, and aggregation of the Glu-BSA model system incubated at 60°C relative to 37°C. This study highlighted that the incubation temperature, purification method and cell exposure time are important variables to consider when generating AGEs in vitro and will enable future studies to better reflect in vivo situations of albumin glycation.
Publisher: Elsevier BV
Date: 12-2022
DOI: 10.1016/J.SCITOTENV.2022.158061
Abstract: Wastewater-based epidemiology is a tool incorporating biomarker analysis that can be used to monitor the health status of a population. Indicators of health include endogenous oxidative stress biomarkers and hormones, or exogenous such as alcohol and nicotine. 8-Iso-prostaglandin F
Publisher: Elsevier BV
Date: 08-2022
DOI: 10.1016/J.SCITOTENV.2022.155696
Abstract: Methcathinone is a prevalent Novel Psychoactive Substance (NPS) used illicitly in some countries. Routine analysis of wastewater s led from catchments in South Australia has shown a consistent low-level presence of the compound, inconsistent with NPS use. This raised the question was the occurrence due to regular use as a drug of choice or was it an artefact being produced from other sources in the sewer system? NPS consumption is generally sporadic and would therefore point to the origin of methcathinone in wastewater being due to in-sewer oxidation of its legal precursor, pseudoephedrine. The present study tested this hypothesis by comparing the levels of pseudoephedrine and methcathinone in wastewater s les collected bimonthly from 8 catchment sites in South Australia. Laboratory experiments exposing pseudoephedrine to common household oxidizing agents (hypochlorite and percarbonate) were also performed and the production of methcathinone was demonstrated and monitored. The results of this study showed that the level of pseudoephedrine and methcathinone measured in wastewater followed a similar pattern. However, there were periods when the levels of each compound erged. Laboratory experiments showed that when exposed to various oxidizing agents, pseudoephedrine is oxidised to non-stoichiometric quantities of methcathinone. Although the use of methcathinone as a drug of choice remains possible, the results of this study indicate that the low and persistent level of methcathinone found in wastewater may arise in part from the oxidation of pseudoephedrine in the sewer system.
Publisher: Oxford University Press (OUP)
Date: 23-01-2020
Abstract: This study investigated the effect of glucose and fructose, and advanced glycation end-products (AGEs) on genome damage in WIL2-NS cells, measured using the cytokinesis-block micronucleus cytome (CBMN-Cyt) assay. The effect of AGEs was investigated using the bovine serum albumin (AGE-BSA) model system induced either with glucose (Glu–BSA) or with fructose (Fru–BSA). Liquid chromatography-mass spectrometry (LC-MS/MS) analysis showed higher Nε-carboxymethyllysine (CML 26.76 ± 1.09 nmol/mg BSA) levels in the Glu–BSA model. Nε-Carboxyethyllysine (CEL 7.87 ± 0.19 nmol/mg BSA) and methylglyoxal-derived hydroimidazolone-1 (MG-H1 69.77 ± 3.74 nmol/mg BSA) levels were higher in the Fru–BSA model. Genotoxic effects were measured using CBMN-Cyt assay biomarkers [binucleated(BN) cells with micronuclei (MNi), BN with nucleoplasmic bridges (NPBs) and BN with nuclear buds (NBuds)] following 9 days of treatment with either glucose, fructose, Glu–BSA or Fru–BSA. Fructose treatment exerted a significant genotoxic dose–response effect including increases of BN with MNi (R2 = 0.7704 P = 0.0031), BN with NPBs (R2 = 0.9311 P & 0.0001) and BN with NBuds (R2 = 0.7118 P = 0.0091) on cells, whereas the DNA damaging effects of glucose were less evident. High concentrations of AGEs (400–600 µg/ml) induced DNA damage however, there was no effect on cytotoxicity indices (necrosis and apoptosis). In conclusion, this study demonstrates a potential link between physiologically high concentrations of reducing sugars or AGEs with increased chromosomal damage which is an important emerging aspect of the pathology that may be induced by diabetes. Ultimately, loss of genome integrity could accelerate the rate of ageing and increase the risk of age-related diseases over the long term. These findings indicate the need for further research on the effects of glycation on chromosomal instability and to establish whether this effect is replicated in humans in vivo.
Publisher: Oxford University Press (OUP)
Date: 08-05-2020
Abstract: The cytokinesis-block micronucleus cytome (CBMNcyt) assay is a comprehensive method to measure DNA damage, cytostasis and cytotoxicity caused by nutritional, radiation and chemical factors. A slide imaging technique has been identified as a new method to assist with the visual scoring of cells for the CBMNcyt assay. A NanoZoomer S60 Digital Pathology slide scanner was used to view WIL2-NS cells treated with hydrogen peroxide (H2O2) and measure CBMNcyt assay biomarkers using a high-definition desktop computer screen. The H2O2-treated WIL2-NS cells were also scored visually using a standard light microscope, and the two visual scoring methods were compared. Good agreement was found between the scoring methods for all DNA damage indices (micronuclei, nucleoplasmic bridges and nuclear buds) and nuclear ision index with correlation R values ranging from 0.438 to 0.789, P & 0.05. Apoptotic and necrotic cell frequency was lower for the NanoZoomer scoring method, but necrotic frequency correlated well with the direct visual microscope method (R = 0.703, P & 0.0001). Considerable advantages of the NanoZoomer scoring method compared to direct visual microscopy includes reduced scoring time, improved ergonomics and a reduction in scorer fatigue. This study indicates that a digital slide scanning and viewing technique may assist with visual scoring for the CBMNcyt assay and provides similar results to conventional direct visual scoring.
Publisher: Elsevier BV
Date: 11-2023
Publisher: Oxford University Press (OUP)
Date: 22-04-2020
Abstract: This study investigated the effect of dietary sugars and advanced glycation end-products (AGE) on telomere dynamics in WIL2-NS cells. Dietary sugars [glucose (Glu) and fructose (Fru) 0.1 M each] were incubated with bovine serum albumin (BSA) (10 mg/ml) at 60 ± 1°C for 6 weeks to generate AGE-BSA. Liquid chromatography-mass spectrometry (LC-MS/MS) analysis showed total AGE levels as 87.74 ± 4.46 nmol/mg and 84.94 ± 4.28 nmol/mg respectively in Glu-BSA and Fru-BSA model. Cell treatment studies using WIL2-NS cells were based on either glucose, fructose (each 2.5–40 mM) or AGE-BSA (200–600 µg/ml) in a dose-dependent manner for 9 days. Telomere length (TL) was measured using qPCR. Nitric oxide (NO) production and tumour necrosis factor-α (TNF-α) levels were measured in WIL2-NS culture medium. An increasing trend for TNF-α and NO production was observed with higher concentration of glucose (R2 = 0.358 P = 0.019 R2 = 0.307 P = 0.027) and fructose (R2 = 0.669 P = 0.001 R2 = 0.339 P = 0.006). A decreasing trend for TL (R2 = 0.828 P = 0.000), and an increasing trend for NO production (R2 = 0.352 P = 0.031) were observed with increasing Glu-BSA concentrations. Fru-BSA treatment did not show significant trend on TL (R2 = 0.135 P = 0.352) with increasing concentration, however, a significant reduction was observed at 600 µg/ml (P & 0.01) when compared to BSA treatment. No trends for TNF-α levels and a decreasing trend on NO production (R2 = 0.5201 P = 0.019) was observed with increasing Fru-BSA treatment. In conclusion, this study demonstrates a potential relationship between dietary sugars, AGEs and telomere attrition. AGEs may also exert telomere shortening through the production of pro-inflammatory metabolites, which ultimately increase the risk of diabetes complications and age-related disease throughout lifespan.
No related grants have been discovered for Emma Jaunay.