Publications by authors named "Lucie Sauzéat"

5 Publications

  • Page 1 of 1

Inter-comparison of stable iron, copper and zinc isotopic compositions in six reference materials of biological origin.

Talanta 2021 Jan 8;221:121576. Epub 2020 Sep 8.

Univ Lyon, ENSL, Univ Lyon 1, CNRS, LGL-TPE, F-69007, Lyon, France. Electronic address:

There is a lack of certified reference materials with an organic matrix for which metal isotope ratios have been certified. Here, we have determined the iron, copper and zinc stable isotopic compositions for six reference materials of biological origin with diverse matrices, i.e. BCR-380R (whole milk), BCR-383 (beans), ERM-CE464 (tuna fish), SRM-1577c (bovine liver), DORM-4 (fish protein) and TORT-3 (lobster hepatopancreas) in three different labs. The concentrations for six major and sixteen trace elements, spanning almost four orders of magnitude, were also measured and the results obtained show an excellent agreement with certified values, demonstrating that the dissolution step was quantitative for all the standards. By taking literature data into account, 39 possible pair-wise comparisons of mean iron, copper and zinc isotopic values (δ values) could be made. Results of Tukey multiple comparisons of means yielded 11 significantly different pairs. Most of these differences are of the same order of magnitude as the estimated mean expanded uncertainties (U, k = 2) (±0.10‰, ±0.05‰, and ±0.05‰ for the δFe, δCu and δZn values, respectively). The present inter-comparison study finally proposes nineteen new preferred values for the Cu, Zn and Fe isotopic compositions of six reference materials of biological origin.
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http://dx.doi.org/10.1016/j.talanta.2020.121576DOI Listing
January 2021

Isotopic Evidence for Disrupted Copper Metabolism in Amyotrophic Lateral Sclerosis.

iScience 2018 Aug 1;6:264-271. Epub 2018 Aug 1.

Université de Lyon, ENS de Lyon, CNRS, LGL-TPE, 69007 Lyon, France. Electronic address:

Redox-active metals are thought to be implicated in neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). To address this point, we measured the concentrations of 12 elements and, for the first time, the stable isotope compositions of copper (redox-active) and zinc (redox-inactive) in human cerebrospinal fluids of 31 patients with ALS, 11 age-matched controls (CTRL), and 14 patients with Alzheimer disease. We first show that metal concentrations weakly discriminate patients with ALS from the two other groups. We then report that zinc isotopic compositions are similar in the three groups, but that patients with ALS have significantly 65copper-enriched isotopic compositions relative to CTRL and patients with AD. This result unambiguously demonstrates that copper is implicated in ALS. We suggest that this copper isotopic signature may result from abnormal protein aggregation in the brain parenchyma, and propose that isotopic analysis is a potential tool that may help unraveling the molecular mechanisms at work in ALS.
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http://dx.doi.org/10.1016/j.isci.2018.07.023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6137708PMC
August 2018

Coral bleaching is linked to the capacity of the animal host to supply essential metals to the symbionts.

Glob Chang Biol 2018 07 17;24(7):3145-3157. Epub 2018 Apr 17.

CNRS UMR 5276 "Laboratoire de Géologie de Lyon", Ecole Normale Supérieure de Lyon, Lyon Cedex 07, France.

Massive coral bleaching events result in extensive coral loss throughout the world. These events are mainly caused by seawater warming, but are exacerbated by the subsequent decrease in nutrient availability in surface waters. It has therefore been shown that nitrogen, phosphorus or iron limitation contribute to the underlying conditions by which thermal stress induces coral bleaching. Generally, information on the trophic ecology of trace elements (micronutrients) in corals, and on how they modulate the coral response to thermal stress is lacking. Here, we demonstrate for the first time that heterotrophic feeding (i.e. the capture of zooplankton prey by the coral host) and thermal stress induce significant changes in micro element concentrations and isotopic signatures of the scleractinian coral Stylophora pistillata. The results obtained first reveal that coral symbionts are the major sink for the heterotrophically acquired micronutrients and accumulate manganese, magnesium and iron from the food. These metals are involved in photosynthesis and antioxidant protection. In addition, we show that fed corals can maintain high micronutrient concentrations in the host tissue during thermal stress and do not bleach, whereas unfed corals experience a significant decrease in copper, zinc, boron, calcium and magnesium in the host tissue and bleach. In addition, the significant increase in δ Cu and δ Zn signature of symbionts and host tissue at high temperature suggests that these isotopic compositions are good proxy for stress in corals. Overall, present findings highlight a new way in which coral heterotrophy and micronutrient availability contribute to coral resistance to global warming and bleaching.
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http://dx.doi.org/10.1111/gcb.14141DOI Listing
July 2018

Metallome evolution in ageing C. elegans and a copper stable isotope perspective.

Metallomics 2018 03 14;10(3):496-503. Epub 2018 Mar 14.

Université de Lyon, ENS de Lyon, CNRS, LGL-TPE, 69007 Lyon, France.

Ageing is accompanied by important chemical deregulations resulting in bodily metal imbalances. The way and extent to which these deregulations are associated with ageing processes are however poorly understood and their use as potential biomarkers of ageing has not been investigated. In this study, we report whole-body elementary concentrations and copper and zinc isotopic compositions of Caenorhabditis elegans in ageing wild type (i.e.'normal'-lived) and mutant (i.e. short and long-lived) strains. We show that the strains are characterized by different levels of mutation-related variations such as in phosphorus and magnesium as well as in zinc isotopic composition. During ageing, strains are affected by elemental age-related variations, such as an increase in calcium and iron concentrations and a decrease in the copper isotopic composition and concentration for long-lived mutants. The deregulated metabolism of copper seems to be connected to ageing probably in association with the production of reactive oxygen species. We emphasize that the copper stable isotope composition could serve as a biomarker of normal or accelerated ageing in the future.
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http://dx.doi.org/10.1039/c7mt00318hDOI Listing
March 2018