Browsing by Autor "Jacques Gardon"

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Arsenic exposure and biomarkers for oxidative stress and telomere length in indigenous populations in Bolivia
(Elsevier BV, 2022) Jessica De Loma; Annette M. Krais; Christian Lindh; Josué Mamani; Noemí Tirado; Jacques Gardon; Karin Bröberg
Arsenic exposure and cancer-related biomarkers in indigenous populations in Bolivia – modification by arsenic metabolism efficiency
(2024) Jessica De Loma; Noemí Tirado; Michael Levi; Jacques Gardon; Karin Bröberg
Inorganic arsenic is a known carcinogen. Telomere length (TL) and mitochondrial DNA copy number (mtDNAcn) in peripheral blood may serve as biomarkers for genotoxicity and cancer risk. Our aim is to assess if arsenic exposure influences TL and mtDNAcn in women living around Lake Poopó (Bolivia) from two ethnicities (Aymara-Quechua and Uru). Arsenic exposure was evaluated as the sum of arsenic metabolite concentrations in urine (U-As) measured by high-performance liquid chromatography online with hydride generation and inductively coupled plasma-mass spectrometry (HPLC-HG-ICP-MS), and as total arsenic in blood (B-As) measured by ICP-MS. Efficiency of arsenic metabolism was evaluated using the relative fractions of urinary metabolites, and arsenic methylating genetics (AS3MT rs3740393 and rs1046778) measured by TaqMan allelic discrimination or chip-based genotyping. TL and mtDNAcn were determined in blood by real-time PCR. Our results show that arsenic exposure (assessed as U-As and B-As) was associated with longer TL and higher mtDNAcn in this study population, and the associations were modified by arsenic metabolism capacity and AS3MT genotype.
Arsenic Exposure and Cancer-Related Proteins in Urine of Indigenous Bolivian Women
(Frontiers Media, 2020) Jessica De Loma; Anda R. Gliga; Michael Levi; Franz Ascui; Jacques Gardon; Noemí Tirado; Karin Bröberg
Indigenous people living in the Bolivian Andes are exposed through their drinking water to inorganic arsenic, a potent carcinogen. However, the health consequences of arsenic exposure in this region are unknown. The aim of this study was to evaluate associations between arsenic exposure and changes in cancer-related proteins in indigenous women (n = 176) from communities around the Andean Lake Poopó, Bolivia. Arsenic exposure was assessed in whole blood (B-As) and urine (as the sum of arsenic metabolites, U-As) by inductively coupled plasma-mass spectrometry (ICP-MS). Cancer-related proteins (N = 92) were measured in urine using the proximity extension assay. The median B-As concentration was 2.1 (range 0.60-9.1) ng/g, and U-As concentration was 67 (12-399) μg/L. Using linear regression models adjusted for age, urinary osmolality, and urinary leukocytes, we identified associations between B-As and four putative cancer-related proteins: FASLG, SEZ6L, LYPD3, and TFPI2. Increasing B-As concentrations were associated with lower protein expression of SEZ6L, LYPD3, and TFPI2, and with higher expression of FASLG in urine (no association was statistically significant after correcting for multiple comparisons). The associations were similar across groups with different arsenic metabolism efficiency, a susceptibility factor for arsenic toxicity. In conclusion, arsenic exposure in this region was associated with changes in the expression of some cancer-related proteins in urine. Future research is warranted to understand if these proteins could serve as valid biomarkers for arsenic-related toxicity.
Blood transcriptome changes linked to long-term arsenic exposure through drinking water – a cross-sectional study from the Bolivian Andes
(Elsevier BV, 2025) Ying Yang; Anastasiia Snigireva; Jessika Barrón Cuenca; Noemí Tirado; Maria Teresa Alvarez Aliaga; Gina Torres; Paolo Manghi; Philippe Gérard; Michael Levi; Jacques Gardon
Child neurodevelopment in a Bolivian mining city
(Elsevier BV, 2011) María Ruiz‐Castell; Pamela Paco; Flavia-Laura Barbieri; Jean‐Louis Duprey; Joan Forns; Anne‐Elie Carsin; Rémi Freydier; Corinne Casiot; Jordi Sunyer; Jacques Gardon
CHILD NEURODEVELOPMENT IN A BOLIVIAN MINING CITY
(National Institute of Environmental Health Sciences, 2011) María Ruiz‐Castell; Pamela Paco; Flavia-Laura Barbieri; Jean‐Louis Duprey; Joan Forns; Anne-Elie Carsina; Rémi Freydier; Corinne Casiot; Jordi Sunyer; Jacques Gardon
Background and Aims: This study evaluates the neurodevelopment of children living near highly contaminated mining industries during their first year of life. Methods: Participants from the city of Oruro (Bolivia) were prospectively recruited during pregnancy and followed-up between May 2007 and November 2009. Questionnaires were used to obtain information regarding the pregnant women’s socioeconomic status, as well as anamnesis. Neurodevelopment was tested on 246 children using the Bayley Scales of Infant Development (BSID) at 10.5 to 12.5 months of age. Trace elements (Pb, As, Cd, Sb, Cs, Zn, Fe, Cu, Se, Rb, Sr) exposure during prenatal life was evaluated by testing maternal blood concentrations before delivery. Results: The blood lead concentration of pregnant women was low, considering the contaminated environmental context. The geometric mean was 1.85µg/dL (95% IC: 1.71; 2.00), a level almost comparable with those observed in non contaminated areas. The only element found to be relatively elevated was antimony, with 1.03µg/dL (95% IC: 0.94; 1.13). The Bayley Scales of Infant Development (BSID) did not reveal mental or psychomotor abnormalities associated to blood levels of trace metals during pregnancy. Almost all levels were lower than the control limits. Conclusion: Our results suggest that women from this mining area were poorly exposed.
Child patterns of growth delay and cognitive development in a bolivian mining city
(Wiley, 2012) María Ruiz‐Castell; Anne‐Elie Carsin; Flavia-Laura Barbieri; Pamela Paco; Jacques Gardon; Jordi Sunyer
In this Bolivian cohort, children born smaller were more likely to grow/develop faster and attain greater weight and length. Their cognitive development was not affected by their growth patterns.
Co-infection withOnchocerca volvulusandLoa loamicrofilariae in central Cameroon: are these two species interacting?
(Cambridge University Press, 2006) Sébastien D. S. Pion; Paul Clarke; João A. N. Filipe; Joseph Kamgno; Jacques Gardon; María‐Gloria Basáñez; Michel Boussinesq
Ivermectin treatment may induce severe adverse reactions in some individuals heavily infected with Loa loa. This hampers the implementation of mass ivermectin treatment against onchocerciasis in areas where Onchocerca volvulus and L. loa are co-endemic. In order to identify factors, including co-infections, which may explain the presence of high L. loa microfilaraemia in some individuals, we analysed data collected in 19 villages of central Cameroon. Two standardized skin snips and 30 mul of blood were obtained from each of 3190 participants and the microfilarial (mf) loads of both O. volvulus and L. loa were quantified. The data were analysed using multivariate hierarchical models. Individual-level variables were: age, sex, mf presence, and mf load; village-related variables included the endemicity levels for each infection. The two species show a certain degree of ecological separation in the study area. However, for a given individual host, the presence of microfilariae of one species was positively associated with the presence of microfilariae of the other (OR=1.79, 95% CI [1.43-2.24]). Among individuals harbouring Loa microfilariae, there was a slight positive relationship between the L. loa and O. volvulus mf loads which corresponded to an 11% increase in L. loa mf load per 100 O. volvulus microfilariae. Co-infection with O. volvulus is not sufficient to explain the very high L. loa mf loads harboured by some individuals.
Ecosistemas alto-andinos del valle de La Paz: aportes a la sociedad y vulnerabilidad frente a los cambios globales
(2015) Fabien Anthelme; Laetitia Perrier Bruslé; Rosa Isela Loza Herrera; Jacques Gardon; Anaïs Zimmer; Rosa Iselas Meneses
capitulo 8
Elevated arsenic exposure and efficient arsenic metabolism in indigenous women around Lake Poopó, Bolivia
(Elsevier BV, 2018) Jessica De Loma; Noemí Tirado; Franz Ascui; Michael Levi; Marie Vahter; Karin Bröberg; Jacques Gardon
Elevated concentrations of inorganic arsenic, one of the most potent environmental toxicants and carcinogens, have been detected in well water around Lake Poopó, Bolivia. This study aimed to assess human exposure to arsenic in villages around Lake Poopó, and also to elucidate whether the metabolism and detoxification of arsenic in this population is as efficient as previously indicated in other Andean areas. We recruited 201 women from 10 villages around Lake Poopó. Arsenic exposure was determined as the sum concentration of arsenic metabolites (inorganic arsenic; monomethylarsonic acid, MMA; and dimethylarsinic acid, DMA) in urine (U-As), measured by HPLC-HG-ICP-MS. Efficiency of arsenic metabolism was assessed by the relative fractions of the urinary metabolites. The women had a wide variation in U-As (range 12-407 μg/L, median 65 μg/L) and a markedly efficient metabolism of arsenic with low %MMA (median 7.7%, range: 2.2-18%) and high %DMA (80%, range: 54-91%) in urine. In multivariable-adjusted linear regression models, ethnicity (Aymara-Quechua vs. Uru), body weight, fish consumption and tobacco smoking were associated with urinary arsenic metabolite fractions. On average, the Uru women had 2.5 lower % (percentage unit) iAs, 2.2 lower %MMA and 4.7 higher %DMA compared with the Aymara-Quechua women. Our study identified several factors that may predict these women's arsenic methylation capacity, particularly ethnicity. Further studies should focus on mechanisms underlying these differences in arsenic metabolism efficiency, and its importance for the risk of arsenic-related health effects.
Genetic polymorphism of the β-tubulin gene of Onchocerca volvulus in ivermectin naïve patients from Cameroon, and its relationship with fertility of the worms
(Cambridge University Press, 2005) Catherine Bourguinat; Sébastien D. S. Pion; Joseph Kamgno; Jacques Gardon; N. Gardon-Wendel; B. O. L. Duke; Roger K. Prichard; Michel Boussinesq
Observations of low response of patients infected with Onchocerca volvulus to ivermectin suggest that the parasite may be under a selection process toward potential resistance. To limit the extension of this phenomenon, it is crucial to characterize the genes of O. volvulus that are involved. For this, O. volvulus adult worms collected before the introduction of ivermectin in an onchocerciasis endemic area of central Cameroon were genotyped for beta-tubulin. To derive a baseline to investigate the selective pressure of ivermectin, we analysed (1) the frequency distribution of the beta-tubulin alleles, and (2) the relationship between the different beta-tubulin related genotypes and the fertility status of the female worms. The frequency of allele b of the beta-tubulin gene was very low, as it was observed in West Africa. We observed a deficit of heterozygous female worms leading to Hardy Weinberg disequilibrium, which might be explained by a shorter life-span of these worms compared to the homozygous worms. Unexpectedly, our results also show that the heterozygous female worms were much less fertile than the homozygotes: more than two thirds of the homozygotes were fertile, whereas only 37% of the heterozygotes were fertile. These results will be further considered when analysing post-treatment data.
Genetic Selection of Low Fertile Onchocerca volvulus by Ivermectin Treatment
(Public Library of Science, 2007) Catherine Bourguinat; Sébastien D. S. Pion; Joseph Kamgno; Jacques Gardon; B. O. L. Duke; Michel Boussinesq; Roger K. Prichard
The results indicate that ivermectin is causing genetic selection on O. volvulus. This genetic selection is associated with a lower reproductive rate in the female parasites. We hypothesize that this genetic selection indicates that a population of O. volvulus, which is more tolerant to ivermectin, is being selected. This selection could have implications for the development of ivermectin resistance in O. volvulus and for the ongoing onchocerciasis control programmes.
Genotoxicity in humans exposed to arsenic and lithium in drinking water in the Bolivian Andes
(2023) Noemí Tirado; Josué Mamani; Jessica De Loma; Franz Ascui; Karin Bröberg; Jacques Gardon
Elevated concentrations of arsenic, lithium and boron in drinking water have already been reported in the Bolivian Andes. Arsenic causes genotoxicity but that caused by lithium and boron is less well known. The aim of the present study was to evaluate associations between arsenic, lithium and boron exposure and genotoxicity, while taking genetic susceptibility into account. Women (n=230) were recruited in ten villages around Lake Poopó. Arsenic exposure was determined as the sum of concentrations of arsenic metabolites (iAs, MMA, and DMA) in urine. Exposure to lithium and boron was determined based on their concentrations in urine. Genetic susceptibility was determined by GSTM1 and GSTT1 null genotypes and AS3MT rs3740393,. Genotoxicity (DNA strand breaks) was measured peripheral blood by the comet assay. Median arsenic, lithium, and boron concentrations were 60 µg/L, 989 µg/L, and 3929 µg/L, respectively. GSTM1 and GSTT1 null carriers showed more DNA strand breaks than gene carriers (p=0.008, p=0.005). We found no correlation between urinary arsenic and DNA strand breaks (rS=0.03, p=0.64), and only a weak non-significant positive association in the multivariate analysis (β=0.09, p=0.14). Unexpectedly, increasing concentrations of lithium in urine were negatively correlated with DNA strand breaks (rS=-0.24, p=0.0006), and the association persisted in multivariate analysis after adjusting for arsenic (β=-0.22, p=0.003). We found no association between boron and DNA strand breaks. The lack of genotoxic effect of arsenic could be associated with the specific metabolic adaptation to arsenic previously reported in this population. The apparent protective effect of lithium against genotoxicity merits further investigation.
Genotoxicity in humans exposed to arsenic, lithium, and boron in drinking water in the Bolivian Andes—A cross sectional study
(Wiley, 2024) Noemí Tirado; Josué Mamani; Jessica De Loma; Franz Ascui; Karin Bröberg; Jacques Gardon
Elevated concentrations of arsenic, lithium and boron in drinking water have already been reported in Bolivia. Arsenic is known to cause genotoxicity but that caused by lithium and boron is less well known. The aim of the present cross-sectional study was to evaluate potential genotoxic effects of exposure to arsenic, while considering exposure to lithium and boron and genetic susceptibility. Women (n = 230) were recruited in villages located around Lake Poopó. Exposure to arsenic was determined as the sum of concentrations of arsenic metabolites inorganic arsenic, monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) in urine. Exposure to lithium and boron was determined based on their concentrations in urine. Genetic susceptibility was determined by GSTM1 (glutathione S-transferase-mu-1) and GSTT1 (glutathione S-transferase-theta-1) null genotypes and AS3MT (Arsenite Methyltransferase) rs3740393. Genotoxicity was measured in peripheral blood leukocytes using the comet assay. The geometric means of arsenic, lithium, and boron concentrations were 68, 897, and 3972 μg/L, respectively. GSTM1 and GSTT1 null carriers had more DNA strand breaks than gene carriers (p = .008, p = .005). We found no correlation between urinary arsenic and DNA strand breaks (rS = .03, p = .64), and only a weak non-significant positive association in the adjusted multivariate analysis (β = .09 [-.03; .22], p = .14). Surprisingly, increasing concentrations of lithium in urine were negatively correlated with DNA strand breaks (rS = -.24, p = .0006), and the association persisted in multivariate analysis after adjusting for arsenic (β = -.22 [-.36; -.08], p = .003). We found no association between boron and DNA strand breaks. The apparent protective effect of lithium merits further investigation.
Hair mercury levels in Amazonian populations: spatial distribution and trends
(BioMed Central, 2009) F. Barbieri; Jacques Gardon
Hair Trace Elements Concentration to Describe Polymetallic Mining Waste Exposure in Bolivian Altiplano
(Springer Science+Business Media, 2010) F. Barbieri; Amandine Cournil; Jorge Eduardo de Souza Sarkis; Eric Bénéfice; Jacques Gardon
Human adaptation to arsenic in Bolivians living in the Andes
(Elsevier BV, 2022) Jessica De Loma; Mário Vicente; Noemí Tirado; Franz Ascui; Marie Vahter; Jacques Gardon; Carina M. Schlebusch; Karin Bröberg
Humans living in the Andes Mountains have been historically exposed to arsenic from natural sources, including drinking water. Enzymatic methylation of arsenic allows it to be excreted more efficiently by the human body. Adaptation to high-arsenic environments via enhanced methylation and excretion of arsenic was first reported in indigenous women in the Argentinean Andes, but whether adaptation to arsenic is a general phenomenon across native populations from the Andes Mountains remains unclear. Therefore, we evaluated whether adaptation to arsenic has occurred in the Bolivian Andes by studying indigenous groups who belong to the Aymara-Quechua and Uru ethnicities and have lived in the Bolivian Andes for generations. Our population genetics methods, including genome-wide selection scans based on linkage disequilibrium patterns and allele frequency differences, in combination with targeted and whole-genome sequencing and genotype-phenotype association analyses, detected signatures of positive selection near the gene encoding arsenite methyltransferase (AS3MT), the main arsenic methylating enzyme. This was among the strongest selection signals (top 0.5% signals via locus-specific branch length and extended haplotype homozygosity tests) at a genome-wide level in the Bolivian study groups. We found a large haplotype block of 676 kb in the AS3MT region and identified candidate functional variants for further analysis. Moreover, our analyses revealed associations between AS3MT variants and the fraction of mono-methylated arsenic in urine and showed that the Bolivian study groups had the highest frequency of alleles associated with more efficient arsenic metabolism reported so far. Our data support the idea that arsenic exposure has been a driver for human adaptation to tolerate arsenic through more efficient arsenic detoxification in different Andean populations.
Indoor metallic pollution and children exposure in a mining city
(Elsevier BV, 2014) Enio Barbieri; Francisco E. Fontúrbel; Cristian Herbas; F. Barbieri; Jacques Gardon
Indoor metallic pollution related to mining activity in the Bolivian Altiplano
(Elsevier BV, 2011) Francisco E. Fontúrbel; Enio Barbieri; Cristian Herbas; F. Barbieri; Jacques Gardon
Influence of source distribution and geochemical composition of aerosols on children exposure in the large polymetallic mining region of the Bolivian Altiplano
(Elsevier BV, 2011) Sylvaine Goix; David Point; Priscia Oliva; Mireille Polvé; Jean Louis Duprey; Hubert Mazurek; Ludivine Guislain; Carlos Huayta; F. Barbieri; Jacques Gardon