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Animals : An Open Access Journal From... Jun 2024Ciguatera is a foodborne disease caused by ciguatoxins (CTXs), produced by dinoflagellates (genera and ), which bioaccumulate in fish through the food web, causing...
Ciguatera is a foodborne disease caused by ciguatoxins (CTXs), produced by dinoflagellates (genera and ), which bioaccumulate in fish through the food web, causing poisoning in humans. Currently, the physiological mechanisms of the species with the highest amount of toxins in their adult stage of life that are capable of causing these poisonings are poorly understood. Dusky grouper () is a relevant fishing species and is part of the CTX food chain in the Canary Islands. This study developed an experimental model of dietary exposure featuring adult dusky groupers with two diets of tissue naturally contaminated with CTXs (amberjack and moray eel flesh) with two different potential toxicities; both groups were studied at different stages of exposure (4, 6, 10, 12, and 18 weeks). The results showed that this species did not show changes in its behavior due to the provided feeding, but the changes were recorded in biochemical parameters (mainly lipid and hepatic metabolism) that may respond to liver damage and alterations in the homeostasis of the fish; more research is needed to understand histopathological and cytotoxic changes.
PubMed: 38929377
DOI: 10.3390/ani14121757 -
International Journal of Environmental... Jun 2024Deoxynivalenol (DON) is a foodborne mycotoxin produced by molds that commonly infect cereal grains. It is a potent protein synthesis inhibitor that can significantly... (Review)
Review
Deoxynivalenol (DON) is a foodborne mycotoxin produced by molds that commonly infect cereal grains. It is a potent protein synthesis inhibitor that can significantly impact humans' gastrointestinal, immune, and nervous systems and can alter the microbiome landscape. Low-dose, chronic exposure to DON has been found to stimulate the immune system, inhibit protein synthesis, and cause appetite suppression, potentially leading to growth failure in children. At higher doses, DON has been shown to cause immune suppression, nausea, vomiting, abdominal pain, headache, diarrhea, gastroenteritis, the malabsorption of nutrients, intestinal hemorrhaging, dizziness, and fever. A provisional maximum tolerable daily intake (PMTDI) limit of 1 µg/kg/body weight has been established to protect humans, underscoring the potential health risks associated with DON intake. While the adverse effects of dietary DON exposure have been established, healthcare communities have not adequately investigated or addressed this threat to child health, possibly due to the assumption that current regulatory exposure limits protect the public appropriately. This integrative review investigated whether current dietary DON exposure rates in infants and children regularly exceed PMTDI limits, placing them at risk of negative health effects. On a global scale, the routine contamination of cereal grains, bakery products, pasta, and human milk with DON could lead to intake levels above PMTDI limits. Furthermore, evidence suggests that other food commodities, such as soy, coffee, tea, dried spices, nuts, certain seed oils, animal milk, and various water reservoirs, can be intermittently contaminated, further amplifying the scope of the issue. Better mitigation strategies and global measures are needed to safeguard vulnerable youth from this harmful toxicant.
Topics: Humans; Trichothecenes; Child; Dietary Exposure; Infant; Food Contamination; Child, Preschool
PubMed: 38929054
DOI: 10.3390/ijerph21060808 -
International Journal of Environmental... May 2024Besides being vectors of the onchocerciasis parasite, blackflies are a source of nuisance in onchocerciasis-endemic communities. We investigated the experience of...
Community Perceptions of Blackfly Nuisance and Acceptability of the "Slash and Clear" Vector Control Approach in the Ntui Health District of Cameroon: A Qualitative Study.
Besides being vectors of the onchocerciasis parasite, blackflies are a source of nuisance in onchocerciasis-endemic communities. We investigated the experience of residents in the Ntui Health District (Cameroon) regarding blackfly nuisance and assessed their perceptions of a novel "Slash and Clear" (S&C) intervention for blackfly control. Focus group discussions were conducted before and after S&C implementation (respectively, in February 2022 and December 2023). Blackflies were known to emerge from the river areas and cause disease. To prevent blackfly bites, the population often covered their body with protective clothing and applied various substances (kerosene, oil, or lemon) to their skin. Post-intervention data showed reduced blackfly nuisance, and the willingness to sustain blackfly control in the long-term was unanimous among community leaders and members, including the village volunteers who implemented the S&C intervention. In conclusion, blackfly nuisance is evident in the Ntui onchocerciasis focus of Cameroon and led to a panoply of coping practices, some of which could be detrimental to their health. Implementing S&C for blackfly control is well accepted and could sustainably alleviate the nuisance caused by blackflies while simultaneously breaking the onchocerciasis transmission cycle.
Topics: Cameroon; Animals; Simuliidae; Humans; Onchocerciasis; Insect Control; Female; Male; Adult; Insect Vectors; Middle Aged; Focus Groups; Health Knowledge, Attitudes, Practice; Young Adult; Insect Bites and Stings
PubMed: 38928904
DOI: 10.3390/ijerph21060658 -
International Journal of Molecular... Jun 2024Humans are continuously exposed to various heavy metals including copper, iron, cadmium, and arsenic, which were specifically selected for the current analysis because... (Review)
Review
Humans are continuously exposed to various heavy metals including copper, iron, cadmium, and arsenic, which were specifically selected for the current analysis because they are among the most frequently encountered environmental mankind and industrial pollutants potentially causing human health hazards and liver injury. So far, these issues were poorly assessed and remained a matter of debate, also due to inconsistent results. The aim of the actual report is to thoroughly analyze the positive as well as negative effects of these four heavy metals on human health. Copper and iron are correctly viewed as pollutant elements essential for maintaining human health because they are part of important enzymes and metabolic pathways. Healthy individuals are prepared through various genetically based mechanisms to maintain cellular copper and iron homeostasis, thereby circumventing or reducing hazardous liver and organ injury due to excessive amounts of these metals continuously entering the human body. In a few humans with gene aberration, however, liver and organ injury may develop because excessively accumulated copper can lead to Wilson disease and substantial iron deposition to hemochromatosis. At the molecular level, toxicities of some heavy metals are traced back to the Haber Weiss and Fenton reactions involving reactive oxygen species formed in the course of oxidative stress. On the other hand, cellular homeostasis for cadmium and arsenic cannot be provided, causing their life-long excessive deposition in the liver and other organs. Consequently, cadmium and arsenic represent health hazards leading to higher disability-adjusted life years and increased mortality rates due to cancer and non-cancer diseases. For unknown reasons, however, liver injury in humans exposed to cadmium and arsenic is rarely observed. In sum, copper and iron are good for the human health of most individuals except for those with Wilson disease or hemochromatosis at risk of liver injury through radical formation, while cadmium and arsenic lack any beneficial effects but rather are potentially hazardous to human health with a focus on increased disability potential and risk for cancer. Primary efforts should focus on reducing the industrial emission of hazardous heavy metals.
Topics: Humans; Arsenic; Iron; Cadmium; Copper; Environmental Exposure; Environmental Pollutants; Chemical and Drug Induced Liver Injury; Liver; Metals, Heavy; Oxidative Stress
PubMed: 38928368
DOI: 10.3390/ijms25126662 -
International Journal of Molecular... Jun 2024An accumulation of reactive oxygen species (ROS) in cardiomyocytes can induce pro-arrhythmogenic late Na currents by removing the inactivation of voltage-gated Na...
An accumulation of reactive oxygen species (ROS) in cardiomyocytes can induce pro-arrhythmogenic late Na currents by removing the inactivation of voltage-gated Na channels including the tetrodotoxin (TTX)-resistant cardiac α-subunit Nav1.5 as well as TTX-sensitive α-subunits like Nav1.2 and Nav1.3. Here, we explored oxidant-induced late Na currents in mouse cardiomyocytes and human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) as well as in HEK 293 cells expressing Nav1.2, Nav1.3, or Nav1.5. Na currents in mouse cardiomyocytes and hiPSC-CMs treated with the oxidant chloramine T (ChT) developed a moderate reduction in peak current amplitudes accompanied by large late Na currents. While ChT induced a strong reduction in peak current amplitudes but only small persistent currents on Nav1.5, both Nav1.2 and Nav1.3 produced increased peak current amplitudes and large persistent currents following oxidation. TTX (300 nM) blocked ChT-induced late Na currents significantly stronger as compared to peak Na currents in both mouse cardiomyocytes and hiPSC-CMs. Similar differences between Nav1.2, Nav1.3, and Nav1.5 regarding ROS sensitivity were also evident when oxidation was induced with UVA-light (380 nm) or the cysteine-selective oxidant nitroxyl (HNO). To conclude, our data on TTX-sensitive Na channels expressed in cardiomyocytes may be relevant for the generation of late Na currents following oxidative stress.
Topics: Myocytes, Cardiac; Humans; Animals; Tetrodotoxin; Mice; Induced Pluripotent Stem Cells; HEK293 Cells; Oxidation-Reduction; Chloramines; Reactive Oxygen Species; NAV1.5 Voltage-Gated Sodium Channel; Sodium; Action Potentials; Tosyl Compounds
PubMed: 38928302
DOI: 10.3390/ijms25126596 -
International Journal of Molecular... Jun 2024The peripheral nervous system can encounter alterations due to exposure to some of the most commonly used anticancer drugs (platinum drugs, taxanes, vinca alkaloids,... (Review)
Review
The peripheral nervous system can encounter alterations due to exposure to some of the most commonly used anticancer drugs (platinum drugs, taxanes, vinca alkaloids, proteasome inhibitors, thalidomide), the so-called chemotherapy-induced peripheral neurotoxicity (CIPN). CIPN can be long-lasting or even permanent, and it is detrimental for the quality of life of cancer survivors, being associated with persistent disturbances such as sensory loss and neuropathic pain at limb extremities due to a mostly sensory axonal polyneuropathy/neuronopathy. In the state of the art, there is no efficacious preventive/curative treatment for this condition. Among the reasons for this unmet clinical and scientific need, there is an uncomplete knowledge of the pathogenetic mechanisms. Ion channels and transporters are pivotal elements in both the central and peripheral nervous system, and there is a growing body of literature suggesting that they might play a role in CIPN development. In this review, we first describe the biophysical properties of these targets and then report existing data for the involvement of ion channels and transporters in CIPN, thus paving the way for new approaches/druggable targets to cure and/or prevent CIPN.
Topics: Humans; Antineoplastic Agents; Peripheral Nervous System Diseases; Ion Channels; Animals; Neurotoxicity Syndromes; Membrane Transport Proteins; Neoplasms
PubMed: 38928257
DOI: 10.3390/ijms25126552 -
International Journal of Molecular... Jun 2024Aflatoxin B (AFB) contamination is a serious threat to nutritional safety and public health. The CotA-laccase from ANSB821 previously reported by our laboratory showed...
Aflatoxin B (AFB) contamination is a serious threat to nutritional safety and public health. The CotA-laccase from ANSB821 previously reported by our laboratory showed great potential to degrade AFB without redox mediators. However, the use of this CotA-laccase to remove AFB in animal feed is limited because of its low catalytic efficiency and low expression level. In order to make better use of this excellent enzyme to effectively degrade AFB, twelve mutants of CotA-laccase were constructed by site-directed mutagenesis. Among these mutants, E186A and E186R showed the best degradation ability of AFB, with degradation ratios of 82.2% and 91.8% within 12 h, which were 1.6- and 1.8-times higher than those of the wild-type CotA-laccase, respectively. The catalytic efficiencies (/K) of E186A and E186R were found to be 1.8- and 3.2-times higher, respectively, than those of the wild-type CotA-laccase. Then the expression vectors pPICZαA-N-E186A and pPICZαA-N-E186R with an optimized signal peptide were constructed and transformed into GS115. The optimized signal peptide improved the secretory expressions of E186A and E186R in GS115. Collectively, the current study provided ideal candidate CotA-laccase mutants for AFB detoxification in food and animal feed and a feasible protocol, which was desperately needed for the industrial production of CotA-laccases.
Topics: Aflatoxin B1; Bacillus licheniformis; Bacterial Proteins; Laccase; Mutagenesis, Site-Directed; Recombinant Proteins; Saccharomycetales
PubMed: 38928160
DOI: 10.3390/ijms25126455 -
International Journal of Molecular... Jun 2024The compound 15-deacetylcalonectrin (15-deCAL) is a common pathway intermediate in the biosynthesis of trichothecenes. This tricyclic intermediate is metabolized to...
The compound 15-deacetylcalonectrin (15-deCAL) is a common pathway intermediate in the biosynthesis of trichothecenes. This tricyclic intermediate is metabolized to calonectrin (CAL) by trichothecene 15--acetyltransferase encoded by . Unlike other trichothecene pathway gene mutants, the Δ mutant produces lower amounts of the knocked-out enzyme's substrate 15-deCAL, and instead, accumulates higher quantities of earlier bicyclic intermediate and shunt metabolites. Furthermore, evolutionary studies suggest that may play a role in shaping the chemotypes of trichothecene-producing strains. To better understand the functional role of Tri3p in biosynthesis and evolution, we aimed to develop a method to produce 15-deCAL by using transgenic strains derived from a trichothecene overproducer. Unfortunately, introducing mutant , encoding a catalytically impaired but structurally intact acetylase, did not improve the low 15-deCAL production level of the Δ deletion strain, and the bicyclic products continued to accumulate as the major metabolites of the active-site mutant. These findings are discussed in light of the enzyme responsible for 15-deCAL production in trichothecene biosynthesis machinery. To efficiently produce 15-deCAL, we tested an alternative strategy of using a CAL-overproducing transformant. By feeding a crude CAL extract to a strain that was isolated in this study and capable of specifically deacetylating C-15 acetyl, 15-deCAL was efficiently recovered. The substrate produced in this manner can be used for kinetic investigations of this enzyme and its possible role in chemotype diversification.
Topics: Fusarium; Trichothecenes; Mutation; Acetyltransferases; Fungal Proteins; Biosynthetic Pathways
PubMed: 38928120
DOI: 10.3390/ijms25126414 -
International Journal of Molecular... Jun 2024In most cases, the number of honeybee stings received by the body is generally small, but honeybee stings can still cause serious allergic reactions. This study fully...
In most cases, the number of honeybee stings received by the body is generally small, but honeybee stings can still cause serious allergic reactions. This study fully simulated bee stings under natural conditions and used H Nuclear Magnetic Resonance (H NMR) to analyze the changes in the serum metabolome of Sprague-Dawley (SD) rats stung once or twice by honeybees to verify the impact of this mild sting on the body and its underlying mechanism. The differentially abundant metabolites between the blank control rats and the rats stung by honeybees included four amino acids (aspartate, glutamate, glutamine, and valine) and four organic acids (ascorbic acid, lactate, malate, and pyruvate). There was no separation between the sting groups, indicating that the impact of stinging once or twice on the serum metabolome was similar. Using the Principal Component Discriminant Analysis ( PCA-DA) and Variable Importance in Projection (VIP) methods, glucose, lactate, and pyruvate were identified to help distinguish between sting groups and non-sting groups. Metabolic pathway analysis revealed that four metabolic pathways, namely, the tricarboxylic acid cycle, pyruvate metabolism, glutamate metabolism, and alanine, aspartate, and glutamate metabolism, were significantly affected by bee stings. The above results can provide a theoretical basis for future epidemiological studies of bee stings and medical treatment of patients stung by honeybees.
Topics: Animals; Bees; Metabolome; Rats; Rats, Sprague-Dawley; Insect Bites and Stings; Male; Metabolic Networks and Pathways; Principal Component Analysis
PubMed: 38928075
DOI: 10.3390/ijms25126365 -
International Journal of Molecular... Jun 2024Eastern Diamondback Rattlesnake () envenomation is a medical emergency encountered in the Southeastern United States. The venom contains a snake venom thrombin-like...
Eastern Diamondback Rattlesnake () envenomation is a medical emergency encountered in the Southeastern United States. The venom contains a snake venom thrombin-like enzyme (SVTLE) that is defibrinogenating, causing coagulopathy without effects on platelets in humans. This investigation utilized thrombelastographic methods to document this coagulopathy kinetically on the molecular level in a rabbit model of envenomation via the analyses of whole blood samples without and with platelet inhibition. Subsequently, the administration of a novel ruthenium compound containing site-directed antivenom abrogated the coagulopathic effects of envenomation in whole blood without platelet inhibition and significantly diminished loss of coagulation in platelet-inhibited samples. This investigation provides coagulation kinetic insights into the molecular interactions and results of SVTLE on fibrinogen-dependent coagulation and confirmation of the efficacy of a ruthenium antivenom. These results serve as a rationale to investigate the coagulopathic effects of other venoms with this model and assess the efficacy of this site-directed antivenom.
Topics: Animals; Rabbits; Antivenins; Crotalus; Crotalid Venoms; Blood Coagulation; Thrombelastography; Ruthenium; Snake Bites; Male; Venomous Snakes
PubMed: 38928044
DOI: 10.3390/ijms25126334