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1.
Neurotoxicology ; 82: 35-44, 2021 01.
Article in English | MEDLINE | ID: mdl-33166614

ABSTRACT

Uranium exposure can lead to neurobehavioral alterations in particular of the monoaminergic system, even at non-cytotoxic concentrations. However, the mechanisms of uranium neurotoxicity after non-cytotoxic exposure are still poorly understood. In particular, imaging uranium in neurons at low intracellular concentration is still very challenging. We investigated uranium intracellular localization by means of synchrotron X-ray fluorescence imaging with high spatial resolution (< 300 nm) and high analytical sensitivity (< 1 µg.g-1 per 300 nm pixel). Neuron-like SH-SY5Y human cells differentiated into a dopaminergic phenotype were continuously exposed, for seven days, to a non-cytotoxic concentration (10 µM) of soluble natural uranyl. Cytoplasmic submicron uranium aggregates were observed accounting on average for 62 % of the intracellular uranium content. In some aggregates, uranium and iron were co-localized suggesting common metabolic pathways between uranium and iron storage. Uranium aggregates contained no calcium or phosphorous indicating that detoxification mechanisms in neuron-like cells are different from those described in bone or kidney cells. Uranium intracellular distribution was compared to fluorescently labeled organelles (lysosomes, early and late endosomes) and to fetuin-A, a high affinity uranium-binding protein. A strict correlation could not be evidenced between uranium and the labeled organelles, or with vesicles containing fetuin-A. Our results indicate a new mechanism of uranium cytoplasmic aggregation after non-cytotoxic uranyl exposure that could be involved in neuronal defense through uranium sequestration into less reactive species. The remaining soluble fraction of uranium would be responsible for protein binding and for the resulting neurotoxic effects.


Subject(s)
Dopaminergic Neurons/metabolism , Uranium/metabolism , Cell Line , Dopaminergic Neurons/chemistry , Humans , Organometallic Compounds/metabolism , Spectrometry, X-Ray Emission , Synchrotrons , Uranium/analysis
2.
PLoS Negl Trop Dis ; 13(12): e0007824, 2019 12.
Article in English | MEDLINE | ID: mdl-31825968

ABSTRACT

BACKGROUND: Domestic carnivores can introduce rabies into disease-free countries or areas if they are incubating the disease and transported during the pre-symptomatic period. For pets moved into the European Union, the European Commission decided to establish a system of community approval of laboratories willing to carry out the rabies serological controls to guarantee an effective control system. As the specific institute to coordinate the approval of the laboratories, designated by the European Commission in 2000, our laboratory organizes annual proficiency tests (PT) for laboratories already agreed or willing to be agreed to perform rabies serological controls (by detecting rabies virus neutralizing antibodies only) in the frame of international trade. METHODOLOGY/PRINCIPAL FINDINGS: The assessment criteria of this PT rely on the analysis of the specificity and the intra-laboratory consistency. The approach used to evaluate the degree of laboratory consistency is based on the use of compiled data obtained from previous PT campaigns, and is measured by the quality of a regression model. By using historical data for calculating assigned values and associated standard deviations, instead of values obtained from only one campaign, they became robust without any additional statistical treatment. In the present paper, more than 800 historical values were compiled for each of the regression parameters. CONCLUSIONS/SIGNIFICANCE: Since the beginning of these PT schemes in 1999, the overall percentage of failing laboratories remained stable over the years (4.1%) while the number of participants increased to 79 in 2018. This highlighted the robustness and the consistency of the statistical analyses used to assess the laboratory's performance over the years. The improvements carried out and the consistency of our statistical analyses have resulted in the compliance of the rabies serology PT with the ISO/IEC 17043 and ISO 13528:2015 International Standards.


Subject(s)
Antibodies, Viral/blood , Dog Diseases/diagnosis , Laboratory Proficiency Testing , Rabies virus/immunology , Rabies/veterinary , Serologic Tests/methods , Animals , Dogs , European Union , Neutralization Tests/methods , Rabies/diagnosis
3.
Vet Res ; 49(1): 84, 2018 08 30.
Article in English | MEDLINE | ID: mdl-30165897

ABSTRACT

The original article [1] contained an error in the Author details paragraph. "5Neglected Zoonotic Diseases, World Health Organization, Geneva, Switzerland" should be replaced by "5Le Grand-Saconnex, Switzerland".

4.
Vet Res ; 49(1): 61, 2018 07 13.
Article in English | MEDLINE | ID: mdl-30005701

ABSTRACT

The mass vaccination of dogs is a proven tool for rabies prevention. Besides parenteral delivery of inactivated vaccines, over the past several decades, several self-replicating biologics, including modified-live, attenuated and recombinant viruses, have been evaluated for the oral vaccination of dogs against rabies. Vaccines are included within an attractive bait for oral consumption by free-ranging dogs. Due to the high affinity between dogs and humans, such biologics intended for oral vaccination of dogs (OVD) need to be efficacious as well as safe. Baits should be preferentially attractive to dogs and not to non-target species. Although many different types have been evaluated successfully, no universal bait has been identified to date. Moreover, high bait acceptance does not necessarily mean that vaccine efficacy and programmatic success is predictable. The use of OVD in the laboratory and field has demonstrated the safety and utility of this technology. Within a One Health context, OVD should be considered as part of a holistic plan for the global elimination of canine rabies.


Subject(s)
Dog Diseases/prevention & control , Rabies Vaccines/administration & dosage , Rabies/veterinary , Vaccination/veterinary , Administration, Oral , Animals , Dogs , Humans , Rabies/prevention & control
5.
Vet Res ; 48(1): 57, 2017 09 22.
Article in English | MEDLINE | ID: mdl-28938920

ABSTRACT

RABORAL V-RG® is an oral rabies vaccine bait that contains an attenuated ("modified-live") recombinant vaccinia virus vector vaccine expressing the rabies virus glycoprotein gene (V-RG). Approximately 250 million doses have been distributed globally since 1987 without any reports of adverse reactions in wildlife or domestic animals since the first licensed recombinant oral rabies vaccine (ORV) was released into the environment to immunize wildlife populations against rabies. V-RG is genetically stable, is not detected in the oral cavity beyond 48 h after ingestion, is not shed by vaccinates into the environment, and has been tested for thermostability under a range of laboratory and field conditions. Safety of V-RG has been evaluated in over 50 vertebrate species, including non-human primates, with no adverse effects observed regardless of route or dose. Immunogenicity and efficacy have been demonstrated under laboratory and field conditions in multiple target species (including fox, raccoon, coyote, skunk, raccoon dog, and jackal). The liquid vaccine is packaged inside edible baits (i.e., RABORAL V-RG, the vaccine-bait product) which are distributed into wildlife habitats for consumption by target species. Field application of RABORAL V-RG has contributed to the elimination of wildlife rabies from three European countries (Belgium, France and Luxembourg) and of the dog/coyote rabies virus variant from the United States of America (USA). An oral rabies vaccination program in west-central Texas has essentially eliminated the gray fox rabies virus variant from Texas with the last case reported in a cow during 2009. A long-term ORV barrier program in the USA using RABORAL V-RG is preventing substantial geographic expansion of the raccoon rabies virus variant. RABORAL V-RG has also been used to control wildlife rabies in Israel for more than a decade. This paper: (1) reviews the development and historical use of RABORAL V-RG; (2) highlights wildlife rabies control programs using the vaccine in multiple species and countries; and (3) discusses current and future challenges faced by programs seeking to control or eliminate wildlife rabies.


Subject(s)
Animals, Wild/virology , Rabies Vaccines/therapeutic use , Rabies/veterinary , Administration, Oral , Animals , Rabies/prevention & control , Rabies Vaccines/administration & dosage , Rabies virus/genetics , Vaccines, Synthetic/therapeutic use , Vaccinia virus/genetics
6.
Vet Res ; 45: 77, 2014 Aug 10.
Article in English | MEDLINE | ID: mdl-25106552

ABSTRACT

The SAG2 vaccine (RABIGEN® SAG2) is a modified live attenuated rabies virus vaccine, selected from the SAD Bern strain in a two-step process of amino acid mutation using neutralizing monoclonal antibodies. The strain is genetically stable and does not spread in vivo or induce a persistent infection. Its absence of residual pathogenicity was extensively demonstrated in multiple target and non target species (such as wild carnivores and rodent species), including non-human primates. The efficacy of SAG2 baits was demonstrated according to the EU requirements for the red fox and raccoon dog. The use of safe and potent rabies vaccines such as SAG2 largely contributed to the elimination of rabies in Estonia, France, Italy and Switzerland. Importantly, these countries were declared free of rabies after few years of oral vaccination campaigns with SAG2 baits distributed with an appropriate strategy. The excellent tolerance of the SAG2 vaccine has been confirmed in the field since its first use in 1993. No safety issues have been reported, and in particular no vaccine-induced rabies cases were diagnosed, after the distribution of more than 20 million SAG2 baits in Europe.


Subject(s)
Foxes , Rabies Vaccines/administration & dosage , Rabies virus/physiology , Rabies/veterinary , Raccoon Dogs , Administration, Oral , Animals , Disease Eradication , Europe , Rabies/prevention & control , Rabies Vaccines/genetics , Rabies Vaccines/standards , Vaccination/veterinary , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/genetics
7.
Endocrinology ; 154(11): 4237-48, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24029240

ABSTRACT

Abnormally high GH/IGF-I levels, most often caused by adenomas arising from pituitary somatotrophs, generate deleterious effects. We recently described a targeted secretion inhibitor (SXN101742) comprising a GHRH domain and the endopeptidase domain of botulinum toxin serotype D (GHRH-light chain endopeptidase type D domain [LC/D] associated to a heavy chain translocation domain [HN]) able to down-regulate the GH/IGF-I axis. In the present study, we compared the effect of a single iv bolus of a related molecule developed for clinical studies (SXN101959, 1 mg/kg) with a sc infusion of the somatostatin analog octreotide (SMS201-995, 10 µg/kg · h) to lower GH/IGF-I activity in growing male rats. Ten days after administration of SXN101959 or initiation of the octreotide infusion, body and pituitary weights, body length, GH peaks, and IGF-I production were reduced by both treatments but to a greater extent with SXN101959. In contrast to unaltered GH gene expression and increased GH storage in pituitaries from octreotide-treated rats, the inhibition of GH secretion was associated with a collapse of both GH mRNA and protein level in pituitaries from SXN101959-treated rats, in line with a specific decrease in hypothalamic GHRH production, not observed with octreotide. SXN101959 did not induce major apoptotic events in anterior pituitary and exhibited a reversible mode of action with full recovery of somatotroph cell functionality 30 days after treatment. Octreotide infusion permanently decreased ghrelin levels, whereas SXN101959 only transiently attenuated ghrelinemia. Both treatments limited bone mass acquisition and altered specifically tissues development. In conclusion, SXN101959 exerts a powerful and reversible inhibitory action on the somatotropic axis. Specific features of SXN101959, including long duration of action coupled to a strong inhibition of pituitary GH synthesis, represent advantages when treating overproduction of GH.


Subject(s)
Botulinum Toxins/pharmacology , Growth Hormone/antagonists & inhibitors , Insulin-Like Growth Factor I/metabolism , Octreotide/pharmacology , Recombinant Fusion Proteins/pharmacology , Animals , Bone Development/drug effects , Growth Hormone/metabolism , Insulin-Like Growth Factor I/genetics , Male , Rats
8.
PLoS One ; 7(11): e50131, 2012.
Article in English | MEDLINE | ID: mdl-23166830

ABSTRACT

Poor fetal growth, also known as intrauterine growth restriction (IUGR), is a worldwide health concern. IUGR is commonly associated with both an increased risk in perinatal mortality and a higher prevalence of developing chronic metabolic diseases later in life. Obesity, type 2 diabetes or metabolic syndrome could result from noxious "metabolic programming." In order to better understand early alterations involved in metabolic programming, we modeled IUGR rat pups through either prenatal exposure to synthetic glucocorticoid (dams infused with dexamethasone 100 µg/kg/day, DEX) or prenatal undernutrition (dams feeding restricted to 30% of ad libitum intake, UN). Physiological (glucose and insulin tolerance), morphometric (automated tissue image analysis) and transcriptomic (quantitative PCR) approaches were combined during early life of these IUGR pups with a special focus on their endocrine pancreas and adipose tissue development. In the absence of catch-up growth before weaning, DEX and UN IUGR pups both presented basal hyperglycaemia, decreased glucose tolerance, and pancreatic islet atrophy. Other early metabolic defects were model-specific: DEX pups presented decreased insulin sensitivity whereas UN pups exhibited lowered glucose-induced insulin secretion and more marked alterations in gene expression of pancreatic islet and adipose tissue development regulators. In conclusion, these results show that before any catch-up growth, IUGR rats present early physiologic, morphologic and transcriptomic defects, which can be considered as initial mechanistic basis of metabolic programming.


Subject(s)
Dexamethasone/adverse effects , Fetal Growth Retardation/metabolism , Malnutrition/metabolism , Prenatal Exposure Delayed Effects/metabolism , Adipose Tissue/growth & development , Adipose Tissue/metabolism , Analysis of Variance , Animals , Blood Glucose/metabolism , Blotting, Western , Body Weights and Measures , C-Peptide/blood , Corticosterone/blood , DNA Primers/genetics , Female , Gene Expression Profiling , Insulin/blood , Insulin Resistance/physiology , Islets of Langerhans/growth & development , Islets of Langerhans/metabolism , Islets of Langerhans/pathology , Leptin/blood , Pregnancy , Radioimmunoassay , Rats , Rats, Sprague-Dawley , Real-Time Polymerase Chain Reaction
9.
J Clin Invest ; 122(9): 3295-306, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22850878

ABSTRACT

Botulinum neurotoxins (BoNTs) are zinc endopeptidases that block release of the neurotransmitter acetylcholine in neuromuscular synapses through cleavage of soluble N-ethylmaleimide-sensitive fusion (NSF) attachment protein receptor (SNARE) proteins, which promote fusion of synaptic vesicles to the plasma membrane. We designed and tested a BoNT-derived targeted secretion inhibitor (TSI) targeting pituitary somatotroph cells to suppress growth hormone (GH) secretion and treat acromegaly. This recombinant protein, called SXN101742, contains a modified GH-releasing hormone (GHRH) domain and the endopeptidase domain of botulinum toxin serotype D (GHRH-LHN/D, where HN/D indicates endopeptidase and translocation domain type D). In vitro, SXN101742 targeted the GHRH receptor and depleted a SNARE protein involved in GH exocytosis, vesicle-associated membrane protein 2 (VAMP2). In vivo, administering SXN101742 to growing rats produced a dose-dependent inhibition of GH synthesis, storage, and secretion. Consequently, hepatic IGF1 production and resultant circulating IGF1 levels were reduced. Accordingly, body weight, body length, organ weight, and bone mass acquisition were all decreased, reflecting the biological impact of SXN101742 on the GH/IGF1 axis. An inactivating 2-amino acid substitution within the zinc coordination site of the endopeptidase domain completely abolished SXN101742 inhibitory actions on GH and IGF1. Thus, genetically reengineered BoNTs can be targeted to nonneural cells to selectively inhibit hormone secretion, representing a new approach to treating hormonal excess.


Subject(s)
Down-Regulation/drug effects , Growth Hormone/metabolism , Growth Inhibitors/pharmacology , Insulin-Like Growth Factor I/metabolism , Recombinant Fusion Proteins/pharmacology , Acromegaly/drug therapy , Animals , Area Under Curve , Body Weight/drug effects , Botulinum Toxins/chemistry , Botulinum Toxins/genetics , Cell Line , Cyclic AMP/metabolism , Dose-Response Relationship, Drug , Growth Hormone/blood , Growth Hormone-Releasing Hormone/chemistry , Growth Hormone-Releasing Hormone/genetics , Growth Inhibitors/chemistry , Growth Plate/drug effects , Growth Plate/growth & development , Growth Plate/pathology , Insulin-Like Growth Factor I/genetics , Liver/metabolism , Male , Organ Size/drug effects , Pituitary Gland/drug effects , Pituitary Gland/metabolism , Pituitary Gland/pathology , Prolactin/metabolism , Protein Structure, Tertiary , Proteolysis , Rats , Rats, Sprague-Dawley , Recombinant Fusion Proteins/chemistry , Vesicle-Associated Membrane Protein 2/chemistry
10.
Vector Borne Zoonotic Dis ; 11(4): 341-7, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21395417

ABSTRACT

INTRODUCTION: In May 2007, five patients with Q fever-like symptoms were reported in an agricultural educational center in the rural southern French town of Florac. An investigation was undertaken to identify the outbreak source and risk factors for infection, and to implement control measures. MATERIALS AND METHODS: We undertook active case finding. Patients were defined as individuals with an unexplained fever of ≥38.5°C who lived in, worked in, or visited Florac between April 1 and June 30, 2007. Patients were confirmed by a positive Q fever serology test. A cross-sectional survey with a seroprevalence component was carried out in the educational center and surrounding area. A standardized questionnaire on known risk factors for the infection was used and serological testing was carried out on finger prick blood specimens from participants. The veterinary services investigated local herds within a 5-mile radius using polymerase chain reaction and serological tests. RESULTS: One hundred twenty-two people were included in the cross-sectional survey. Eighteen serologically confirmed acute cases were identified, of whom 12 were from the educational center. The statistical analysis showed an independent association between acute infection and living or working near an area where manure had been spread (p = 0.0.042) and male gender (p = 0.022). Frequenting the educational center's canteen was also associated with infection (p = 0.008) among staff and students. The veterinary investigations identified 11 of the 26 tested flocks of goats and sheep as seropositive for Coxiella burnetii, including 2 ovine flocks located northwest of Florac that had high shedding levels of the bacterium. DISCUSSION: The observed excess of cases of Q fever in Florac, an area endemic for this infection, in spring 2007 could be explained by an aerial transmission from infectious ovine flocks situated close to the town. All local herd owners were re-educated about the risks and prevention practices for Q fever.


Subject(s)
Coxiella burnetii/isolation & purification , Disease Outbreaks , Q Fever/epidemiology , Q Fever/transmission , Adult , Aged , Agriculture , Animal Husbandry , Animals , Antibodies, Bacterial/blood , Cattle , Coxiella burnetii/immunology , Cross-Sectional Studies , Disease Outbreaks/prevention & control , Disease Outbreaks/statistics & numerical data , Female , France/epidemiology , Goats , Humans , Logistic Models , Male , Manure/microbiology , Middle Aged , Polymerase Chain Reaction , Q Fever/blood , Q Fever/prevention & control , Risk Factors , Seasons , Seroepidemiologic Studies , Sheep , Surveys and Questionnaires
11.
Int J Dev Neurosci ; 29(1): 37-43, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20955774

ABSTRACT

In recent years, considerable research has focused on the biological effect of endocrine-disrupting chemicals. Bisphenol A (BPA) has been implicated as an endocrine-disrupting chemical (EDC) due to its ability to mimic the action of endogenous estrogenic hormones. The aim of this study was to assess the effect of perinatal exposure to BPA on cerebral structural development and metabolism after birth. BPA (1mg/l) was administered in the drinking water of pregnant dams from day 6 of gestation until pup weaning. At postnatal day 20, in vivo metabolite concentrations in the rat pup hippocampus were measured using high field proton magnetic resonance spectroscopy. Further, brain was assessed histologically for growth, gross morphology, glial and neuronal development and extent of myelination. Localized proton magnetic resonance spectroscopy ((1)H MRS) showed in the BPA-exposed rat a significant increase in glutamate concentration in the hippocampus as well as in the Glu/Asp ratio. Interestingly these two metabolites are metabolically linked together in the malate-aspartate metabolic shuttle. Quantitative histological analysis revealed that the density of NeuN-positive neurons in the hippocampus was decreased in the BPA-treated offspring when compared to controls. Conversely, the density of GFAP-positive astrocytes in the cingulum was increased in BPA-treated offspring. In conclusion, exposure to low-dose BPA during gestation and lactation leads to significant changes in the Glu/Asp ratio in the hippocampus, which may reflect impaired mitochondrial function and also result in neuronal and glial developmental alterations.


Subject(s)
Brain , Endocrine Disruptors/pharmacology , Estrogens, Non-Steroidal/pharmacology , Lactation/drug effects , Phenols/pharmacology , Prenatal Exposure Delayed Effects , Animals , Aspartic Acid/metabolism , Benzhydryl Compounds , Brain/drug effects , Brain/embryology , Brain/growth & development , Energy Metabolism/drug effects , Female , Glutamic Acid/metabolism , Humans , Magnetic Resonance Spectroscopy/methods , Male , Neuroglia/drug effects , Neuroglia/metabolism , Neurons/drug effects , Neurons/metabolism , Pregnancy , Rats , Rats, Sprague-Dawley
12.
Environ Toxicol Chem ; 30(1): 103-11, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20853451

ABSTRACT

The frequency of occurrence and relative concentration of 44 pesticides in apicultural (Apis mellifera) matrices collected from five French locations (24 apiaries) were assessed from 2002 to 2005. The number and nature of the pesticides investigated varied with the matrices examined-living honeybees, pollen loads, honey, and beeswax. Pollen loads and beeswax had the highest frequency of pesticide occurrence among the apiary matrices examined in the present study, whereas honey samples had the lowest. The imidacloprid group and the fipronil group were detected in sufficient amounts in all matrices to allow statistical comparisons. Some seasonal variation was shown when residues were identified in pollen loads. Given the results (highest frequency of presence) and practical aspects (easy to collect; matrix with no turnover, unlike with bees that are naturally renewed), pollen loads were the best matrix for assessing the presence of pesticide residues in the environment in our given conditions.


Subject(s)
Bees/metabolism , Environmental Monitoring/methods , Environmental Pollutants/metabolism , Pesticides/metabolism , Animals , Environmental Pollutants/analysis , Environmental Pollution/statistics & numerical data , France , Honey/analysis , Models, Biological , Pesticides/analysis , Pollen/chemistry , Waxes/chemistry
13.
Vet Res ; 41(6): 54, 2010.
Article in English | MEDLINE | ID: mdl-20423694

ABSTRACT

Until the late 1980s, specific viral infections of the honey bee were generally considered harmless in all countries. Then, with the worldwide introduction of the ectoparasite mite Varroa destructor, beekeepers encountered increasing difficulties in maintaining their colonies. Epidemiological surveys and laboratory experiments have demonstrated that the newly acquired virulence of several viruses belonging to the family Dicistroviridae (acute bee paralysis virus, Kashmir bee virus and Israeli acute paralysis virus) in Europe and the USA had been observed in relation with V. destructor acting as a disseminator of these viruses between and within bee colonies and as an activator of virus multiplication in the infected individuals: bee larvae and adults. Equal emphasis is given to deformed wing virus (DWV) belonging to the Iflaviridae. Overt outbreaks of DWV infections have been shown to be linked to the ability of V. destructor to act not only as a mechanical vector of DWV but also as a biological vector. Its replication in mites prior to its vectoring into pupae seemed to be necessary and sufficient for the induction of a overt infection in pupae developing in non-viable bees with deformed wings. DWV in V. destructor infested colonies is now considered as one of the key players of the final collapse. Various approaches for combating bee viral diseases are described: they include selection of tolerant bees, RNA interference and prevention of new pathogen introduction. None of these approaches are expected to lead to enhanced bee-health in the short term.


Subject(s)
Bees/parasitology , Bees/virology , Dicistroviridae/physiology , Animals , Host-Parasite Interactions , Host-Pathogen Interactions , Varroidae/physiology
14.
Bone ; 46(6): 1574-81, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20178866

ABSTRACT

INTRODUCTION: Isocaloric protein undernutrition is associated with decreased bone mass and decreased bone strength, together with lower IGF-I levels. It remains unclear whether administration of growth hormone (GH) corrects these alterations in bone metabolism. MATERIALS AND METHODS: Six-month-old female rats were fed isocaloric diets containing either 2.5% or 15% casein for 2 weeks. Bovine growth hormone (bGH, 0.5 or 2.5mg/kg of body weight) or vehicle was then administered as subcutaneous injections, twice daily, to rats on either diet for 4 weeks. At the proximal tibia, analysis of bone mineral density (BMD), maximal load and histomorphometry were performed. In addition, urinary deoxypyridinoline, plasma osteocalcin and IGF-I concentrations were measured. Weight was monitored weekly. RESULTS: bGH caused a dose-dependent increase in plasma IGF-I regardless of the dietary protein content. However, bGH dose-dependently decreased BMD and bone strength in rats fed the low-protein diet. There was no significant effect of bGH on BMD in rats fed the normal protein diet within this short-term treatment period, however bone formation as detected by histomorphometry was improved in this group but not the low-protein group. Osteoclast surface was increased in the low-protein bGH-treated animals only. Changes in bone turnover markers were detectable under both normal and low-protein diets. CONCLUSION: These results emphasize the major importance of dietary protein intake in the bone response to short-term GH administration, and highlight the need for further investigation into the effects of GH treatment in patients with reduced protein intake.


Subject(s)
Bone Density/drug effects , Bone and Bones/drug effects , Bone and Bones/physiology , Growth Hormone/pharmacology , Animals , Biomechanical Phenomena/drug effects , Body Weight , Bone and Bones/metabolism , Caseins , Cattle , Diet, Protein-Restricted/adverse effects , Female , Muscle, Skeletal/drug effects , Rats , Rats, Sprague-Dawley
15.
Environ Health Perspect ; 117(10): 1549-55, 2009 Oct.
Article in English | MEDLINE | ID: mdl-20019905

ABSTRACT

BACKGROUND: The causes of the current obesity pandemic have not been fully elucidated. Implication of environmental endocrine disruptors such as bisphenol A (BPA) on adipose tissue development has been poorly investigated. OBJECTIVES: The aim of the present study was to evaluate the effects of perinatal exposure to BPA on early adipose storage at weaning. METHODS: Pregnant Sprague-Dawley rats had access to drinking water containing 1 mg/L BPA from day 6 of gestation through the end of lactation. Pups were weaned on postnatal day (PND) 21. At that time, we investigated perigonadal adipose tissue of pups (weight, histology, gene expression). For the remaining animals, we recorded body weight and food intake for animals on either standard chow or a high-fat diet. RESULTS: Gestational exposure to BPA did not alter the sex ratio or litter size at birth. On PND1, the weight of male and female BPA-exposed pups was increased. On PND21, body weight was increased only in females, in which parametrial white adipose tissue (pWAT) weight was increased about 3-fold. This excess of pWAT was associated with adipocyte hypertrophy and overexpression of lipogenic genes such as C/EBP-alpha (CAAT enhancer binding protein alpha), PPAR-gamma (peroxisome proliferator-activated receptor gamma), SREBP-1C (sterol regulatory element binding protein-1C), LPL (lipoprotein lipase), FAS (fatty acid synthase), and SCD-1 (stearoyl-CoA desaturase 1). In addition, gene expression of SREBP-1C, FAS, and ACC (acetyl-CoA carboxylase) was also increased in liver from BPA-exposed females at PND21, without a change in circulating lipids and glucose. After weaning, perinatal BPA exposure predisposed to overweight in a sex- and diet-dependent manner. We observed no change in food intake due to perinatal BPA exposure in rats on either standard chow or a high-fat diet. CONCLUSIONS: Perinatal exposure to a low dose of BPA increased adipogenesis in females at weaning. Adult body weight may be programmed during early life, leading to changes dependent on the sex and the nutritional status. Although further studies are required to understand the mechanisms of BPA action in early life, these results are particularly important with regard to the increasing prevalence of childhood obesity and the context-dependent action of endocrine disruptors.


Subject(s)
Adipogenesis/drug effects , Adipose Tissue/drug effects , Environmental Pollutants/toxicity , Gene Expression Regulation, Developmental/drug effects , Phenols/toxicity , Prenatal Exposure Delayed Effects/chemically induced , Adipose Tissue/embryology , Adipose Tissue/metabolism , Animals , Benzhydryl Compounds , Body Weight/drug effects , CCAAT-Enhancer-Binding Protein-alpha/genetics , Female , Gene Expression Regulation, Developmental/genetics , In Vitro Techniques , Lipogenesis/drug effects , Litter Size/drug effects , Liver/metabolism , Male , PPAR gamma/genetics , Pregnancy , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Sex Ratio , Sterol Regulatory Element Binding Protein 1/genetics , Weaning
16.
Environ Entomol ; 38(3): 514-23, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19508759

ABSTRACT

A 3-yr field survey was carried out in France, from 2002 to 2005, to study honey bee (Apis mellifera L.) colony health in relation to pesticide residues found in the colonies. This study was motivated by recent massive losses of honey bee colonies, and our objective was to examine the possible relationship between low levels of pesticide residues in apicultural matrices (honey, pollen collected by honey bees, beeswax) and colony health as measured by colony mortality and adult and brood population abundance. When all apicultural matrices were pooled together, the number of pesticide residue detected per sampling period (four sampling periods per year) and per apiary ranged from 0 to 9, with the most frequent being two (29.6%). No pesticide residues were detected during 12.7% of the sampling periods. Residues of imidacloprid and 6- chloronicotinic acid were the most frequently detected in pollen loads, honey, and honey bee matrices. Several pairs of active ingredients were present concurrently within honey bees and in pollen loads but not in beeswax and honey samples. No statistical relationship was found between colony mortality and pesticide residues. When pesticide residues from all matrices were pooled together, a mixed model analysis did not show a significant relationship between the presence of pesticide residues and the abundance of brood and adults, and no statistical relationship was found between colony mortality and pesticide residues. Thus, although certain pesticide residues were detected in apicultural matrices and occasionally with another pesticide residual, more work is needed to determine the role these residues play in affecting colony health.


Subject(s)
Bees/drug effects , Insecticides/adverse effects , Pesticide Residues/adverse effects , Animal Husbandry , Animals , France , Honey/analysis , Insecticides/analysis , Pesticide Residues/analysis , Waxes/analysis
18.
Mol Cell Endocrinol ; 304(1-2): 69-77, 2009 May 25.
Article in English | MEDLINE | ID: mdl-19433250

ABSTRACT

Presently, a growing interest is focused on the origins of the "Metabolic Syndrome", a cluster of several metabolic disorders linking obesity, dyslipidemia, hypertension and type 2 diabetes mellitus. Clearly, genetic predisposition and deleterious lifestyle, including low physical activity and hypercaloric alimentation, have an influence on the occurrence of the Metabolic Syndrome. However, recent data suggest that the Metabolic Syndrome could also be "programmed" during intrauterine life by diverse insults to the growing foetus. Nicotine is the main stimulant and dependence-forming alkaloid found in tobacco, and despite medical advice, statistics show that 20-30% of female smokers continue the habit during gestation, representing around 10% of all pregnancies. In consequence, nicotine is one of the most universally dangerous chemicals to which developing foetuses are exposed. The present review focuses on recent epidemiological surveys and experimental animal studies that provide evidences indicating that pre- and postnatal nicotine exposure might be a contributing factor for the occurrence of metabolic disorders later in life.


Subject(s)
Cardiovascular Diseases/metabolism , Fetus/drug effects , Metabolic Diseases/metabolism , Nicotine/pharmacology , Prenatal Exposure Delayed Effects , Animals , Blood Glucose/metabolism , Cardiovascular Diseases/etiology , Female , Homeostasis , Humans , Nicotine/adverse effects , Nicotine/metabolism , Obesity/etiology , Obesity/metabolism , Pancreas/drug effects , Pancreas/physiology , Pregnancy , Smoking/adverse effects
19.
Endocrinology ; 149(12): 6289-99, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18687784

ABSTRACT

Despite medical advice, 20-30% of female smokers continue to smoke during pregnancy. Epidemiological studies have associated maternal smoking with increased risk of obesity and type-2 diabetes in the offspring. In the present study, we investigated the impact of prenatal nicotine exposure (3 mg/kg in Sprague Dawley rats via osmotic Alzet minipumps) on the early endocrine pancreas and adipose tissue development in rat pups before weaning. Body weight, fat deposition, food intake and food efficiency, cold tolerance, spontaneous physical activity, glucose utilization, and insulin sensitivity were also examined at adulthood. Prenatal nicotine exposure led to a decrease in endocrine pancreatic islet size and number at 7 d of life (postnatal d 7), which corroborates with a decrease in gene expression of specific transcription factors such as pancreatic and duodenal homeobox 1, Pax-6, Nkx6.1, and of hormones such as insulin and glucagon. The prenatal nicotine exposure also led to an increase in epididymal white adipose tissue weight at weaning (postnatal d 21), and marked hypertrophy of adipocytes, with increased gene expression of proadipogenic transcription factors such as CAAT-enhancer-binding protein-alpha, peroxisome proliferator activated receptor-gamma, and sterol regulatory element binding protein-1C. These early tissue alterations led to significant metabolic consequences, as shown by increased body weight and fat deposition, increased food efficiency on high-fat diet, cold intolerance, reduced physical activity, and glucose intolerance combined with insulin resistance observed at adulthood. These results prove a direct association between fetal nicotine exposure and offspring metabolic syndrome with early signs of dysregulations of adipose tissue and pancreatic development.


Subject(s)
Body Weight/drug effects , Glucose/metabolism , Islets of Langerhans/drug effects , Nicotine/toxicity , Prenatal Exposure Delayed Effects/metabolism , Adipogenesis/drug effects , Adipose Tissue/drug effects , Adipose Tissue/growth & development , Adipose Tissue/metabolism , Animals , Calorimetry , Carbohydrate Metabolism/drug effects , Eating/drug effects , Female , Ganglionic Stimulants/administration & dosage , Ganglionic Stimulants/toxicity , Glucose Tolerance Test , Insulin Resistance , Islets of Langerhans/growth & development , Male , Nicotine/administration & dosage , Pregnancy , Prenatal Exposure Delayed Effects/chemically induced , Prenatal Exposure Delayed Effects/physiopathology , Rats , Rats, Sprague-Dawley
20.
Vet Microbiol ; 124(3-4): 286-97, 2007 Oct 06.
Article in English | MEDLINE | ID: mdl-17532581

ABSTRACT

Performances of an ELISA, an immunofluorescence assay (IFA) and a complement fixation test (CFT) were assessed for detecting antibodies against Coxiella burnetii after Q fever abortions in naturally infected goats. The goal of the study was to provide information useful for veterinary serodiagnosis in regard to categories of goats either experiencing Q fever abortion or not, blood sampling times and recommended cut-offs. The study was conducted on eight goat herds with evidence of C. burnetii abortions. In each herd, at least 5 goats that had aborted and 10 goats prior to parturition or at term were monitored 15, 30 and 60 days (D15, D30, D60) after the onset of Q fever abortion. The overall CFT results distribution did not differ between the two groups of goats and showed poor agreement with the ELISA results. In contrast, the ELISA and IFA results revealed comparable significant differences, but overall the ELISA test was slightly more sensitive than the IFA test. Seroprevalence, according to ELISA and IFA respectively, was higher in the aborting (88% and 82%) than in the non-aborting group (60% and 50%). High levels of serum antibodies were detected in goats post-abortion with an average of 114 %OD using ELISA and a log10(titer) of 2.4 using IFA. Strongly positive ELISA (%OD>80) and positive IFA results (log10(titers)>1.9) were significantly associated with abortion. Sampling on D15 gave the best association with ORs of 10 for ELISA and 6 for IFA. The practical interest of these results is discussed.


Subject(s)
Antibodies, Bacterial/blood , Coxiella burnetii/immunology , Goat Diseases/diagnosis , Q Fever/veterinary , Abortion, Veterinary/diagnosis , Abortion, Veterinary/microbiology , Animals , Antigens, Bacterial/immunology , Complement Fixation Tests/methods , Complement Fixation Tests/standards , Complement Fixation Tests/veterinary , Coxiella burnetii/isolation & purification , Diagnosis, Differential , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/standards , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Fluorescent Antibody Technique, Indirect/methods , Fluorescent Antibody Technique, Indirect/standards , Fluorescent Antibody Technique, Indirect/veterinary , Goat Diseases/epidemiology , Goats , Pregnancy , Q Fever/diagnosis , Q Fever/epidemiology , Reproducibility of Results , Sensitivity and Specificity , Seroepidemiologic Studies
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