Studying the Impact of Persistent Organic Pollutants Exposure on Human Health by Proteomic Analysis: A Systematic Review.

Persistent organic pollutants (POPs) are organic chemical substances that are widely distributed in environments around the globe. POPs accumulate in living organisms and are found at high concentrations in the food chain. Humans are thus continuously exposed to these chemical substances, in which they exert hepatic, reproductive, developmental, behavioral, neurologic, endocrine, cardiovascular, and immunologic adverse health effects. However, considerable information is unknown regarding the mechanism by which POPs exert their adverse effects in humans, as well as the molecular and cellular responses involved. Data are notably lacking concerning the consequences of acute and chronic POP exposure on changes in gene expression, protein profile, and metabolic pathways. We conducted a systematic review to provide a synthesis of knowledge of POPs arising from proteomics-based research. The data source used for this review was PubMed. This study was carried out following the PRISMA guidelines. Of the 742 items originally identified, 89 were considered in the review. This review presents a comprehensive overview of the most recent research and available solutions to explore proteomics datasets to identify new features relevant to human health. Future perspectives in proteomics studies are discussed.

Marine Neurotoxins' Effects on Environmental and Human Health: An OMICS Overview.

Harmful algal blooms (HAB), and the consequent release of toxic metabolites, can be responsible for seafood poisoning outbreaks. Marine wildlife can accumulate these toxins throughout the food chain, which presents a threat to consumers' health. Some of these toxins, such as saxitoxin (STX), domoic acid (DA), ciguatoxin (CTX), brevetoxin (BTX), tetrodotoxin (TTX), and ß-N-methylamino-L-alanine (BMAA), cause severe neurological symptoms in humans. Considerable information is missing, however, notably the consequences of toxin exposures on changes in gene expression, protein profile, and metabolic pathways. This information could lead to understanding the consequence of marine neurotoxin exposure in aquatic organisms and humans. Nevertheless, recent contributions to the knowledge of neurotoxins arise from OMICS-based research, such as genomics, transcriptomics, proteomics, and metabolomics. This review presents a comprehensive overview of the most recent research and of the available solutions to explore OMICS datasets in order to identify new features in terms of ecotoxicology, food safety, and human health. In addition, future perspectives in OMICS studies are discussed.

Guidance Level for Brevetoxins in French Shellfish.

Brevetoxins (BTXs) are marine biotoxins responsible for neurotoxic shellfish poisoning (NSP) after ingestion of contaminated shellfish. NSP is characterized by neurological, gastrointestinal and/or cardiovascular symptoms. The main known producer of BTXs is the dinoflagellate Karenia brevis, but other microalgae are also suspected to synthesize BTX-like compounds. BTXs are currently not regulated in France and in Europe. In November 2018, they have been detected for the first time in France in mussels from a lagoon in the Corsica Island (Mediterranean Sea), as part of the network for monitoring the emergence of marine biotoxins in shellfish. To prevent health risks associated with the consumption of shellfish contaminated with BTXs in France, a working group was set up by the French Agency for Food, Environmental and Occupational Health & Safety (Anses). One of the aims of this working group was to propose a guidance level for the presence of BTXs in shellfish. Toxicological data were too limited to derive an acute oral reference dose (ARfD). Based on human case reports, we identified two lowest-observed-adverse-effect levels (LOAELs). A guidance level of 180 µg BTX-3 eq./kg shellfish meat is proposed, considering a protective default portion size of 400 g shellfish meat.

Pinnatoxins' Deleterious Effects on Cholinergic Networks: From Experimental Models to Human Health.

Pinnatoxins (PnTXs) are emerging neurotoxins that were discovered about 30 years ago. They are solely produced by the marine dinoflagellate Vulcanodinium rugosum, and may be transferred into the food chain, as they have been found in various marine invertebrates, including bivalves. No human intoxication has been reported to date although acute toxicity was induced by PnTxs in rodents. LD50 values have been estimated for the different PnTXs through the oral route. At sublethal doses, all symptoms are reversible, and no neurological sequelae are visible. These symptoms are consistent with impairment of central and peripheral cholinergic network functions. In fact, PnTXs are high-affinity competitive antagonists of nicotinic acetylcholine receptors (nAChRs). Moreover, their lethal effects are consistent with the inhibition of muscle nAChRs, inducing respiratory distress and paralysis. Human intoxication by ingestion of PnTXs could result in various symptoms observed in episodes of poisoning with natural nAChR antagonists. This review updates the available data on PnTX toxicity with a focus on their mode of action on cholinergic networks and suggests the effects that could be extrapolated on human physiology.

Targeted identification of sialoglycoproteins in hypoxic endothelial cells and validation in zebrafish reveal roles for proteins in angiogenesis.

The formation of new vessels in the tumor, termed angiogenesis, is essential for primary tumor growth and facilitates tumor invasion and metastasis. Hypoxia has been described as one trigger of angiogenesis. Indeed, hypoxia, which is characterized by areas of low oxygen levels, is a hallmark of solid tumors arising from an imbalance between oxygen delivery and consumption. Hypoxic conditions have profound effects on the different components of the tumoral environment. For example, hypoxia is able to activate endothelial cells, leading to angiogenesis but also thereby initiating a cascade of reactions involving neutrophils, smooth muscle cells, and fibroblasts. In addition, hypoxia directly regulates the expression of many genes for which the role and the importance in the tumoral environment remain to be completely elucidated. In this study, we used a method to selectively label sialoglycoproteins to identify new membrane and secreted proteins involved in the adaptative process of endothelial cells by mass spectrometry-based proteomics. We used an in vitro assay under hypoxic condition to observe an increase of protein expression or modifications of glycosylation. Then the function of the identified proteins was assessed in a vasculogenesis assay in vivo by using a morpholino strategy in zebrafish. First, our approach was validated by the identification of sialoglycoproteins such as CD105, neuropilin-1, and CLEC14A, which have already been described as playing key roles in angiogenesis. Second, we identified several new proteins regulated by hypoxia and demonstrated for the first time the pivotal role of GLUT-1, TMEM16F, and SDF4 in angiogenesis.

Label-free quantification and shotgun analysis of complex proteomes by one-dimensional SDS-PAGE/NanoLC-MS: evaluation for the large scale analysis of inflammatory human endothelial cells.

To perform differential studies of complex protein mixtures, strategies for reproducible and accurate quantification are needed. Here, we evaluated a quantitative proteomic workflow based on nanoLC-MS/MS analysis on an LTQ-Orbitrap-VELOS mass spectrometer and label-free quantification using the MFPaQ software. In such label-free quantitative studies, a compromise has to be found between two requirements: repeatability of sample processing and MS measurements, allowing an accurate quantification, and high proteomic coverage of the sample, allowing quantification of minor species. The latter is generally achieved through sample fractionation, which may induce experimental bias during the label-free comparison of samples processed, and analyzed independently. In this work, we wanted to evaluate the performances of MS intensity-based label-free quantification when a complex protein sample is fractionated by one-dimensional SDS-PAGE. We first tested the efficiency of the analysis without protein fractionation and could achieve quite good quantitative repeatability in single-run analysis (median coefficient of variation of 5%, 99% proteins with coefficient of variation <48%). We show that sample fractionation by one-dimensional SDS-PAGE is associated with a moderate decrease of quantitative measurement repeatability while largely improving the depth of proteomic coverage. We then applied the method for a large scale proteomic study of the human endothelial cell response to inflammatory cytokines, such as TNFα, interferon γ, and IL1ß, which allowed us to finely decipher at the proteomic level the biological pathways involved in endothelial cell response to proinflammatory cytokines.

First Observations of a Potential Association Between Accumulation of Per- and Polyfluoroalkyl Substances in the Central Nervous System and Markers of Alzheimer's Disease.

The entire human population is exposed to persistent organic pollutants throughout their lives. Among them, per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals widely used in industrial and consumer products that are known to exert adverse effects on human health. As they bioaccumulate in the human brain and are known to be neurotoxic in experimental models, they are assumed to be involved in neurodegenerative processes. In this proof-of-concept study, we measured the level of 18 PFAS in cerebrospinal fluid (CSF) from 8 patients hospitalized with suspected normal pressure hydrocephalus. We then analyzed whether PFAS levels could be related to both biological and clinical markers of Alzheimer's disease. We showed that PFAS and perfluorooctanesulfonate were found in all CSF samples from a French region without fluorochemical industries. Moreover, we observed a significant difference between the levels of PFAS and perfluorooctanesulfonate in the CSF of patients with both Alzheimer's disease markers and cognitive impairment compared with those with only 1 or neither. Two previous studies have shown that PFAS levels in human CSF increase with age and are linked to impaired blood-brain barrier integrity. Our results provide the first evidence of a link between PFAS accumulation in the central nervous system and clinical and biological markers of Alzheimer's disease.

Cerebrospinal fluid proteomic profile of frailty: Results from the PROLIPHYC cohort.

Frailty is a clinical state reflecting a decrease in physiological reserve capacities, known to affect numerous biological pathways and is associated with health issues, including neurodegenerative diseases. However, how global protein expression is affected in the central nervous system in frail subject remains underexplored. In this post hoc cross-sectional biomarker analysis, we included 90 adults (52-85 years) suspected of normal pressure hydrocephalus (NPH) and presenting with markers of neurodegenerative diseases. We investigated the human proteomic profile of cerebrospinal fluid associated with frailty defined by an established cumulated frailty index (FI, average = 0.32), not enriched for neurology clinical features. Using a label-free quantitative proteomic approach, we identified and quantified 999 proteins of which 13 were positively associated with frailty. Pathway analysis with the top positively frailty-associated proteins revealed enrichment for proteins related to inflammation and immune response. Among the 60 proteins negatively associated with frailty, functional pathways enriched included neurogenesis, synaptogenesis and neuronal guidance. We constructed a frailty prediction model using ridge regression with 932 standardized proteins. Our results showed that the "proteomic model" could become an equivalent predictor of FI in order to study chronological age. This study represents the first comprehensive exploration of the proteomic profile of frailty within cerebrospinal fluid. It sheds light on the physiopathology of frailty, particularly highlighting processes of neuroinflammation and inhibition of neurogenesis. Our findings unveil a range of biological mechanisms that are dysregulated in frailty, in NPH subjects at risk of neurodegenerative impairment, offering new perspectives on frailty phenotyping and prediction.

Association Between Homocysteine, Frailty and Biomechanical Response of the CNS in NPH-Suspected Patients.

Frailty is a geriatric syndrome that combines physiological decline, disruptions of homeostatic mechanisms across multiple physiologic systems and thus, strong vulnerability to further pathological stress. Previously, we provided the first evidence that increased risk of poor health outcomes, as quantified by a frailty index (FI), is associated with an alteration of the central nervous system (CNS) biomechanical response to blood pulsatility. In this study, we explored correlation between 14 biological parameters, the CNS elastance coefficient and FI. We included 60 adults (52-92 years) suspected of normal pressure hydrocephalus and presenting with markers of multiple coexisting brain pathologies, including Parkinson disease, Alzheimer disease, and vascular dementia. We showed that the homocysteine (Hcy) level was independently and positively associated with both the FI and the CNS elastance coefficient (adjusted R² of 10% and 6%). We also demonstrated that creatinine clearance and folate level were independently associated with Hcy level. Based on previous literature results describing the involvement of Hcy in endothelial dysfunction, glial activation, and neurodegeneration, we discuss how Hcy could contribute to the altered biomechanical response of the CNS and frailty.

Human poisonings by neurotoxic phycotoxins related to the consumption of shellfish: study of cases registered by the French Poison Control Centres from 2012 to 2019.

CONTEXT: In June 2019, a paralytic shellfish poisoning (PSP) case related to the consumption of mussels contaminated by saxitoxins at a concentration below the regulatory threshold came to the attention of the French Agency for Food, Environmental and Occupational Health and Safety (ANSES). This pointed to probable undetected human cases of poisoning by neurotoxic phycotoxins. METHODS: We conducted a retrospective study of poisoning cases by bivalve shellfish (oysters, mussels and scallops) recorded by the French Poison Control Centres (PCC) from 2012 to 2019. All medical records were reviewed by a toxicologist.Cases that could be related to neurotoxic phycotoxins were selected and described. Diagnosis was based on symptoms compatible with ingestion of contaminated shellfish and on contamination data for the shellfish production area (analysed by the French Research Institute for Exploitation of the Sea, Ifremer), or notifications to the European Rapid Alert System for Food and Feed when the origin of the shellfish was known. RESULTS: Among the 619 shellfish poisoning cases recorded by the PCCs from 2012 to 2019, 22% (n = 134) had reported at least one neurological symptom (headache, dizziness or paraesthesia). Review of medical records for the 134 patients led to suspicion of 14 cases of PSP and one case of amnesic shellfish poisoning. Five patients experienced persistent neurological symptoms. Marine toxins were not tested for in the blood or urine of these patients. CONCLUSION: This retrospective identification of cases strongly suspected of being related to neurotoxic phycotoxins led ANSES, PCCs and Ifremer to develop a specific questionnaire and to recommend actions to take when neurological symptoms related to shellfish consumption are reported to a PCC. Daily monitoring of shellfish poisoning cases registered in the national PCCs database was also implemented in order to rapidly detect any suspicious cases, alert the competent authorities, and warn the general population.

Poison control centres and alternative forms of communication: comparison of response rates between text message and telephone follow-up.

INTRODUCTION: In recent years, the number of patients managed by poison control centres (PCCs) has increased without a proportional increase in the number of physicians. To improve efficiency without neglecting patient follow-up, some PCCs have begun using text messages. We evaluated the difference in response rates between text messaging and traditional telephone follow-up. MATERIALS AND METHODS: This retrospective, monocentric, non-randomised cohort study was conducted using data from calls made by the New Aquitaine PCC between February 27, 2019, and March 31, 2019. Patients were contacted up to three times by a phone call or short message service (SMS). RESULTS: For the analysis, 823 patients were included. At the end of follow-up, the response rates were similar in the phone call and SMS group (94 vs. 94%; p = 0.76) with median [interquartile range] response times of 0 min [0; 27 min] and 29 min [6; 120 min], respectively. The response rates did not differ in subgroups stratified according to sex, self-poisoning vs. relative response, age class, and solicitation during working hours vs. outside of working hours (all p > 0.5). Moreover, health practitioners required 2.4-fold more time to call than to send text messages (p < 0.001), and all practitioners were satisfied or very satisfied with text messaging implementation. CONCLUSION: Patients had good adherence to text messages. Text messages are easy to use, rapid, and allow the physician to easily prioritise follow-up without occupying the emergency line. Additionally, the costs of installation and maintenance are low for text message systems; these low costs facilitate the implementation of such services in various medical situations.

Ocular Lesions Other Than Stings Following Yellow-Legged Hornet (Vespa velutina nigrithorax) Projections, as Reported to French Poison Control Centers.

Importance: Since the accidental introduction of the yellow-legged hornet (Vespa velutina nigrithorax) in France in 2004, there have been reports of this insect unexpectedly projecting a liquid toward the human face, but ocular morbidity associated with this is unknown, to our knowledge. Objective: To describe a case series of ocular lesions after exposure to a liquid projection emitted by a hornet. Design, Setting, and Participants: This was an analysis of all cases of ocular exposure to a projection by a yellow-legged hornet (excluding stings in the eye) collected by French poison control centers between January 1, 2004, and December 31, 2019. Main Outcomes and Measures: Symptoms were evaluated, and a fluorescein eye stain test was used. Results: Twenty-nine cases were recorded (24 in male and 5 in female patients; median age, 40 [interquartile range, 11] years); the first occurred in 2009. Most cases (20 [80%]) were occupational exposure among professionals dealing with hornet nests (eg, firefighters, wasp exterminators). Symptoms consistent with conjunctivitis often resolved quickly after ocular decontamination, but 5 patients developed a periorbital edema, 2 experienced radiating neuropathic pain, and 2 experienced keratitis. Conclusions and Relevance: These findings suggest that the projection of a liquid into the eyes by the yellow-legged hornet presents a new risk to human health, but its precise nature remains to be determined. Ocular lesions had a favorable outcome. For professionals who deal with these insects, adaptation of the usual protections designed for native hymenopterans may be warranted.

Ciguatera fish poisoning in France: experience of the French Poison Control Centre Network from 2012 to 2019.

INTRODUCTION: Ciguatera fish poisoning (CFP) is a common Poisoning in the tropical countries. France is directly concerned with French tourists in endemic area and with French citizens living in the French overseas territories. METHOD: Retrospective, descriptive study of CFP cases handled by the French Poison Control Centre Network from 2012 through 2019. RESULTS: Fifty-two events were studied concerning 130 patients. The fish species was identified for 41 events, mainly belonging to five fish families: 14 groupers, 11 snappers, 5 jacks, 4 parrotfishes, 4 barracudas. The origin of the fish was the Atlantic Ocean (23 events), the Indian Ocean (17 events) and the Pacific Ocean (12 events). 91% of the poisonings occurring in the Atlantic Ocean began with gastrointestinal effects while in 44% of events occurring in the Pacific Ocean, the patients had no gastrointestinal effects (onset with neurological symptoms: paraesthesia and dysesthesia). The evolution of the 130 patients has been classic for CFP with persistent symptoms during 1 to 45 weeks. Numerous patients reported exacerbation of neurological signs several months after poisoning following consumption of alcoholic beverages (23 patients) or seafood (19 patients). DISCUSSION: Medical practitioners in Europe must be trained to manage CFP as cases are reported with tourists returning from endemic areas but also with poisoned patients far from tropical areas after consumption of imported fish.

Health risk assessment related to pinnatoxins in French shellfish.

Pinnatoxins (PnTXs) are a group of emerging marine biotoxins produced by the benthic dinoflagellate Vulcanodinium rugosum, currently not regulated in Europe or in any other country in the world. In France, PnTXs were detected for the first time in 2011, in mussels from the Ingril lagoon (South of France, Mediterranean coast). Since then, analyses carried out in mussels from this lagoon have shown high concentrations of PnTXs for several months each year. PnTXs have also been detected, to a lesser extent, in mussels from other Mediterranean lagoons and on the Atlantic and Corsican coasts. In the French data, the main analog is PnTX G (low levels of PnTX A are also present in some samples). No cases of PnTXs poisoning in humans have been reported so far in France or anywhere else in the world. In mice, PnTXs induce acute neurotoxic effects, within a few minutes after oral administration. Clinical signs of toxicity include decreased mobility, paralysis of the hind legs, tremors, jumps and breathing difficulties leading to death by respiratory arrest at high doses. The French agency for food safety (ANSES) recently conducted a review of the state of knowledge related to PnTXs and V. rugosum. Based on (i) the clinical signs of toxicity in mice, (ii) the mode of action of PnTXs as nicotinic acetylcholine receptor competitive antagonists and (iii) knowledge on drugs and natural toxins with PnTX-related pharmacology, potential human symptoms have been extrapolated and proposed. In this work, a provisional acute benchmark value for PnTX G of 0.13 µg/kg bw per day has been derived from an oral acute toxicity study in mice. Based on this value and a large shellfish meat portion size of 400g, a concentration lower than 23 µg PnTX G/kg shellfish meat is not expected to result in adverse effects in humans. ANSES recommends taking into account PnTXs in the French official monitoring program for shellfish production and identified data gaps to refine health risk assessment.

Snake bites by European vipers in Mainland France in 2017-2018: comparison of two antivenoms Viperfav® and Viperatab®.

Context: Today, immunotherapy with Fab or F(ab')2 fragments is considered as a gold standard treatment for patients bitten by vipers. We compared the efficiency of two antivenoms, Viperfav® and Viperatab®, in mainland France in 2017-2018 with data provided by the French poison control centre (PCC).Methods: Patients with a moderate (2a and 2b) or severe (3) envenomation after a European viper bite and treated with immunotherapy were included and the markers chosen were the risk of post-antivenom treatment worsening, duration of hospital stay and persistent functional discomfort on day 15. Statistical studies were based on multivariate data analysis.Results: Two hundred and ninety-seven cases were recorded. One hundred and eighty-two (61.3%) patients received Viperfav® and 115 (38.7%) received Viperatab®. Compared to Viperfav®, use of Viperatab® significantly increased the risk of post-antivenom treatment worsening (OR* 12.05; 95%CI [3.11; 46.70]; p < .001). No significant difference between these antivenoms was recorded with respect to the duration of hospital stay and persistent functional discomfort on day 15. Viperfav® and Viperatab® have a similar tolerance (p > .21). Otherwise, duration of hospitalisation was significantly increased by a delay of immunotherapy infusion of more than 12 h (OR 2.70; 95%CI [1.45-5.06]; p = .002) or a preventive administration of LMWH (OR 6.55; 95%CI [1.58-27.13]; p=.02).Discussion: While Viperfav® and Viperatab® have a similar tolerance, our data show that Viperatab® was associated with a higher risk of post-antivenom treatment worsening compared to Viperfav®. Furthermore, this study confirms that the antivenom should be used as soon as possible. Indeed, patients receiving the immunotherapy infusion from the grade 2b presented significantly more frequent exacerbated symptoms (OR 3.99; 95%CI [1.16-13.73]; p=.028) after the antivenom infusion compared to grade 2a group.Conclusions: Whereas no significant difference between these antivenoms was recorded with respect to the duration of hospital stay and persistent functional discomfort on day 15, use of Viperatab®, compared to Viperfav®, significantly increased the risk of post-antivenom treatment worsening (OR* 12.05; 95%CI [3.11; 46.70]; p < .001). Taken together, these data show that Viperfav® is the treatment of choice for the management of snake bites in France.

GPCR-jacking: from a new route in RTK signalling to a new concept in GPCR activation.

A large body of evidence indicates that agonists of some G protein-coupled receptors (GPCRs) can activate growth factor receptor tyrosine kinases (RTKs) in the absence of added growth factor. This phenomenon, called transactivation, is an important pathway that contributes to growth-promoting activity of many GPCR ligands. Reciprocally, recent advances indicate that RTKs utilize GPCR signalling molecules to transduce signals and that RTK ligands themselves can transactivate GPCRs. This novel transactivation process, which places GPCR signalling downstream of RTKs, either requires the production of a GPCR ligand of the transactivated GPCR or occurs in a ligand independent manner within an integrated signalling network. Here, we provide an overview of the molecular mechanisms involved in this novel cross-communication between GPCRs and RTKs and discuss its relevance in the specification of growth factor signalling and functions.

Assessment of Translocator Protein Density, as Marker of Neuroinflammation, in Major Depressive Disorder: A Pilot, Multicenter, Comparative, Controlled, Brain PET Study (INFLADEP Study).

Background: Major depressive disorder (MDD) is a serious public health problem with high lifetime prevalence (4.4-20%) in the general population. The monoamine hypothesis is the most widespread etiological theory of MDD. Also, recent scientific data has emphasized the importance of immuno-inflammatory pathways in the pathophysiology of MDD. The lack of data on the magnitude of brain neuroinflammation in MDD is the main limitation of this inflammatory hypothesis. Our team has previously demonstrated the relevance of [18F] DPA-714 as a neuroinflammation biomarker in humans. We formulated the following hypotheses for the current study: (i) Neuroinflammation in MDD can be measured by [18F] DPA-714; (ii) its levels are associated with clinical severity; (iii) it is accompanied by anatomical and functional alterations within the frontal-subcortical circuits; (iv) it is a marker of treatment resistance. Methods: Depressed patients will be recruited throughout 4 centers (Bordeaux, Montpellier, Tours, and Toulouse) of the French network from 13 expert centers for resistant depression. The patient population will be divided into 3 groups: (i) experimental group-patients with current MDD (n = 20), (ii) remitted depressed group-patients in remission but still being treated (n = 20); and, (iii) control group without any history of MDD (n = 20). The primary objective will be to compare PET data (i.e., distribution pattern of neuroinflammation) between the currently depressed group and the control group. Secondary objectives will be to: (i) compare neuroinflammation across groups (currently depressed group vs. remitted depressed group vs. control group); (ii) correlate neuroinflammation with clinical severity across groups; (iii) correlate neuroinflammation with MRI parameters for structural and functional integrity across groups; (iv) correlate neuroinflammation and peripheral markers of inflammation across groups. Discussion: This study will assess the effects of antidepressants on neuroinflammation as well as its role in the treatment response. It will contribute to clarify the putative relationships between neuroinflammation quantified by brain neuroimaging techniques and peripheral markers of inflammation. Lastly, it is expected to open innovative and promising therapeutic perspectives based on anti-inflammatory strategies for the management of treatment-resistant forms of MDD commonly seen in clinical practice. Clinical trial registration (reference: NCT03314155): https://www.clinicaltrials.gov/ct2/show/NCT03314155?term=neuroinflammation&cond=depression&cntry=FR&rank=1.