Sensitive Animal Species Research Articles

Balancing Rare Species Conservation with Extractive Industries

The Colorado Plateau has abundant oil, gas, and alternative energy potential. This energy potential is scattered among a patchwork of land ownership, with private, tribal, and public lands being actively developed for energy extraction. Elements of biodiversity (e.g., listed and sensitive plant and animal species) are distributed among all land tenures, yet the laws protecting them can vary as a function of land tenure. It is imperative to understand the spatial distributions of threatened endangered, and sensitive species in relation to land tenure to preserve habitat and conserve species populations in areas undergoing energy development. We developed species distribution models and spatial conservation optimization frameworks to explore the interactions among land ownership, existing and potential energy extraction, and biodiversity. Four management scenarios were tested to quantify how different approaches to energy extraction may impact rare plant distributions. Results show that incorporating risk and land tenure in spatially optimized frameworks it is possible to facilitate the long-term viability of rare plant species. The scenarios developed here represent a different attitude towards the value of rare plants and the risk of energy development. Results gives insight into the financial consequences of rare species protection and quantifies the biodiversity costs of energy development across landscapes.

First Description of Serological Evidence for SARS-CoV-2 in Lactating Cows.

Simple SummarySevere Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is the agent of the disease that has caused a global pandemic, known as coronavirus disease 2019 (COVID-19). Coronaviruses (CoVs) may emerge from wildlife hosts and infect humans and animals. Up to now, natural infection with SARS-CoV-2 has been reported in several animals, but it has not been found in farm animals, such as buffaloes, goats, sheep, horses, rabbits, hens, pigs, or cows, despite contact with their SARS-CoV-2-positive human breeders. Furthermore, a low susceptibility to SARS-CoV-2 has been detected in experimentally infected cattle with SARS-CoV-2. The unknown zoonotic potential of this virus is a cause of concern for pet owners and farmers. The limited data on cattle suggest that cattle show low susceptibility to SARS-CoV-2 and probably do not function as reservoirs. However, in areas with large cattle populations and a high prevalence of SARS-CoV-2 infection in humans, close contact between livestock and farmworkers may cause reverse zoonotic infections in cattle, as has already been described for highly sensitive animal species, such as minks, cats, and dogs. Thus, studying the zoonotic characteristics of SARS-CoV-2 could help in the development of a strategy for virus detection and the control of viral dissemination.Following the COVID-19 epidemic outbreak in Ariano Irpino, Campania region (Italy), we tested lactating cows for the presence of SARS-CoV-2 on a cattle farm at which, prior to the investigation, 13 of the 20 farmworkers showed COVID-19-like symptoms, and one of them died. Twenty-four lactating cows were sampled to detect SARS-CoV-2. All nasal and rectal swabs and milk samples were negative for SARS-CoV-2 RNA. Of the 24 collected serum samples, 11 showed antibodies against SARS-CoV-2 nucleocapsid protein, 14 showed antibodies against SARS-CoV-2 spike protein, and 13 developed neutralising antibodies for SARS-COV-2; all samples were negative for Bovine Coronavirus (BCoV), another betacoronavirus. To our knowledge, this is the first report of natural serological evidence of SARS-CoV-2 infection in lactating cows. We hypothesise that this may be a case of reverse zoonosis. However, the role of cattle in SARS-CoV-2 infection and transmission seems to be negligible.

Геоинформационное обеспечение и планирование познавательного экотуризма для организации рекреационной деятельности на особо охраняемых природных территориях озера Байкал

The paper considers the features of planning of educational ecological tourism on specially protected areas based on geosystem research and methods of geoinformation mapping. These approaches take into account the distribution of unique and sensitive landscapes, rare plant and animal species and the dynamics peculiarities of local geosystems and their components for designing recreational infrastructure in accordance with the requirements of environmental protection. As a result, the influence of the tourist activity factor and recreational using on certain sections of protected areas is reduced. The model plots are located within the FSE Zapovednoe Podlemor'e in the Zabaikalsky National Park and the Barguzinsky Reserve. A planning scheme of educational tourism is developed. It has a number of logical steps from the idea origin to the design of a route and excursion projection. Fundamental approaches of physical-geographical and landscape research, geoinformation analysis and landscape-interpretation mapping, methods of quantitative and qualitative (scoring) assessment, monitoring analysis are the scientific basis for the work. Authors carried out a number of fieldwork in the study area for a complex geographical analysis of the territory. A specific unit geoinformation database was created for key plots using ArcGIS and other programs. It contains basic information about the research area, for example, landscape characteristics, degree of disturbance and resistance to impact, the unique and rare plants and animals, available infrastructure, proposed routes, etc. Collected information and created thematic maps is a basis for development of scenarios for the planning of educational tourist activity at the model plots. Proposed scenarios take into account their landscapeecological, recreational and infrastructural features. The algorithm can be replicated for other Russian protected areas with similar legal, managerial, and socio-economic conditions.

The Influence of Fusarium Mycotoxins on the Liver of Gilts and Their Suckling Piglets.

Simple SummaryMycotoxins are toxic secondary metabolites of fungi that frequently contaminate animal feed and human food in different combinations; therefore, it is of great importance to determine the effects of mycotoxin co-contamination. Pigs are one of the most sensitive animal species to Fusarium mycotoxins, and the liver is an important site of mycotoxin metabolism. The objective of the present research was to determine histopathological changes, apoptosis, and proliferation in the liver of gilts fed with Fusarium mycotoxin-contaminated feed for a prolonged time at the end of their pregnancy and until weaning of their piglets. Additionally, the same parameters were evaluated in the liver of their piglets to determine whether Fusarium mycotoxins would affect the offspring. The results revealed increased hepatocellular necrosis and apoptosis as well as sinusoidal leukocytosis with inflammatory infiltrates of hepatic lobules in experimental gilts, but no significant changes were observed in the piglet livers, implying that the utilized concentrations and duration of exposure did not cause detrimental effects on them. Interestingly, the amount of interlobular connective tissue in the liver of experimental gilts was significantly decreased. The obtained results emphasized the need to evaluate Fusarium mycotoxin concentrations in feed because even at low concentrations, they can cause adverse effects, but there is less concern for severe detrimental effects on the offspring.Mycotoxins are common fungal secondary metabolites in both animal feed and human food, representing widespread toxic contaminants that cause various adverse effects. Co-contamination with different mycotoxins is frequent; therefore, this study focused on feed contaminated with Fusarium mycotoxins, namely, deoxynivalenol (5.08 mg/kg), zearalenone (0.09 mg/kg), and fusaric acid (21.6 mg/kg). Their effects on the liver of gilts and their piglets were chosen as the research subject as pigs are one of the most sensitive animal species that are also physiologically very similar to humans. The gilts were fed the experimental diet for 54 ± 1 day, starting late in their pregnancy and continuing until roughly a week after weaning of their piglets. Livers of gilts and their piglets were assessed for different histopathological changes, apoptosis, and proliferation activity of hepatocytes. On histopathology, gilts fed the experimental diet had a statistically significant increase in hepatocellular necrosis and apoptosis (p = 0.0318) as well as sinusoidal leukocytosis with inflammatory infiltrates of hepatic lobules (p = 0.0004). The amount of interlobular connective tissue in the liver of experimental gilts was also significantly decreased (p = 0.0232), implying a disruption in the formation of fibrous connective tissue. Apoptosis of hepatocytes and of cells in hepatic sinusoids, further assessed by the terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay, showed a statistically significant increase (p = 0.0224 and p = 0.0007, respectively). No differences were observed in piglet livers. These results indicated that Fusarium mycotoxins elicited increased apoptosis, necrosis, and inflammation in the liver of gilts, but caused no effects on the liver of piglets at these concentrations.

Tetanus in Animals — Summary of Knowledge

Abstract Tetanus is a neurologic non-transmissible disease (often fatal) of humans and other animals with a worldwide occurrence. Clostridium tetani is the spore producing bacillus which causes the bacterial disease. In deep penetrating wounds the spores germinate and produce a toxin called tetanospasmin. The main characteristic sign of tetanus is a spastic paralysis. A diagnosis is usually based on the clinical signs because the detection in the wound and the cultivation of C. tetani is very difficult. Between animal species there is considerable variability in the susceptibility to the bacillus. The most sensitive animal species to the neurotoxin are horses. Sheep and cattle are less sensitive and tetanus in these animal species are less common. Tetanus in cats and dogs are rare and dogs are less sensitive than cats. Clinically two forms of tetanus have been recognized, i. e. localized and generalized. The available treatment is not specific because the toxin in neuronal cells cannot be accessed by antitoxin antibodies. The aim of the therapy is to: neutralise the unbound neurotoxin, inhibit C. tetani growth in the wound, and provide supportive care to mitigate the effects of the neurotoxin. The treatment is difficult with an unclear prognosis.

The role of protein kinase C alpha in tri-ortho-cresyl phosphate-induced autophagy in human neuroblastoma SK-N-SH cells.

As an organophosphorus ester, tri-ortho-cresyl phosphate (TOCP) has been widely used in agriculture and industry. It is reported that TOCP can induce organophosphate-induced delayed neuropathy (OPIDN) in sensitive animal and human species. However, the exact molecular mechanisms underlying TOCP-induced neurotoxicity are still unknown. In this study, we found that TOCP could induce autophagy by activating protein kinase C alpha (PKCα) signaling in neuroblastoma SK-N-SH cells. PKCα activators could positively regulate TOCP-induced autophagy by increasing the expression levels of neighbor BRCA1 gene protein 1 (NBR1), LC3 and P62 autophagic receptor protein. Furthermore, PKCα activation impaired the ubiquitin-proteasome system (UPS), resulting in inhibition of proteasome activity and accumulation of ubiquitinated proteins. UPS dysfunction could stimulate autophagy to serve as a compensatory pathway, which contributed to the accumulation of the abnormally hyperphosphorylated tau proteins and degradation of impaired proteins of the MAP 2 and NF-H families in neurodegenerative disorders.

An assessment of non-consumptive recreation effects on wildlife: current and future research, management implications, and next steps

Most research on the effects of non-consumptive recreation on wildlife to date has focused on birds and mammals. This research typically focuses on behavioral responses of individuals despite practical limitations in extrapolating ecological outcomes from individual behavior. Data gaps therefore present difficulties in integrating wildlife-protective policies into public access management. These gaps are exacerbated by a lack of wildlife studies that include data on public use patterns of open space areas. In a survey of park and open space managers in the San Francisco Bay Area, few of the entities surveyed restricted recreational access permanently or seasonally to address biological constraints; yet most indicated the presence of sensitive plant or animal species on their lands or stated conservation as one of their organization’s purposes. To better bridge the gap between research and management practice, more research is needed on species beyond birds and mammals. This research should extend beyond noting behavioral response and should integrate investigation of outdoor recreation use patterns.

Determination of 27 Elements in Animal Feed by Inductively Coupled Plasma-Mass Spectrometry.

A method was developed to determine 27 elements (aluminum, arsenic, boron, cadmium, calcium, chromium, cobalt, copper, iron, lead, magnesium, manganese, mercury, molybdenum, nickel, phosphorus, potassium, selenium, sodium, sulfur, vanadium, zinc, antimony, uranium, beryllium, thallium, and thorium) in animal feeds and pet foods using closed vessel microwave digestion and inductively coupled plasma-mass spectrometry. These elements can adversely affect animal health when amounts become excessive or deficient in food. For potentially toxic elements, the target LOQ was determined to be 1/10 the lowest maximum tolerable level (MTL) for the most sensitive animal species. For nutritionally essential elements, the target LOQ was determined to be 1/10 the concentration that would be considered deficient in feed if that level is lower than 1/10 the lowest MTL. The targeted high end of the quantitation range was selected as twice the highest MTL. A single-laboratory validation (SLV) was performed to determine the accuracy and precision of the method, and the results were evaluated with respect to predetermined performance characteristics. The test materials used in the SLV included two National Institute of Standards and Technology certified reference materials, two Association of American Feed Control Officials (AAFCO) check samples, and one in-house previously analyzed feed sample. The concentrations of each element determined were the result of spiked analyte, incurred analyte, or a combination of spiked and incurred analyte. All samples were analyzed seven times on different days at 2 × LOQ and at the midrange concentration. For most data, the results of the SLV met or exceeded the criteria for accuracy and repeatability. For accuracy, K at the midrange level had a mean recovery of 95%, which is just below the low preferred accuracy threshold of 97%. For repeatability, all the 2 × LOQ CVr values were below the preferred values. Be, Cr, Ni, Na, Mn, and S all had midrange CVr values exceeding the preferred values. Be had the highest midrange CVr value of 9.93. Eight AAFCO check samples were also analyzed to determine the method's accuracy and repeatability for elements at the manufacturer's claimed levels. For accuracy, all results had z-scores <1.5. For repeatability, three CVr values from two AAFCO check samples were greater than the preferred limits.

Antimicrobial Activity of Essential Oils Against the Fungal Pathogens Ascosphaera apis and Pseudogymnoascus destructans.

Fungal pathogens are a growing worldwide concern. Declines in a number of economically and agriculturally important plant and animal species pose a significant threat to both biodiversity and food security. Although many effective antifungal agents have been identified, their toxicity often precludes their use with food products or sensitive animal species. This has prompted the exploration of natural products as effective treatment compounds. In the present study, several essential oils were tested for their capacity to limit the growth of the fungal pathogens Ascosphaera apis and Pseudogymnoascus destructans, the causative agents of chalkbrood disease among honey bee larvae and white-nose syndrome among bats, respectively. Essential oils of cinnamon bark, citronella, lemongrass, and orange were exposed to A. apis in contact-dependent oil-agar suspensions as well as in contact-independent shared airspaces. Essential oils of cinnamon bark, citronella, and lemongrass were exposed to P. destructans in contact-dependent oil-agar suspensions. All compounds were found to significantly inhibit mycelial growth at low concentrations, suggesting the potential for these natural products to be used for controlling these and other select fungal pathogens.

Diclofenac-induced biochemical changes in nephrotoxicity among male Albino rats

Background: Nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with adverse renal effects caused by the reduction in synthesis of renal prostaglandins in sensitive persons or animal species, and potentially during long-term use in non-sensitive persons if resistance to side effects decreases with age. The effects of diclofenac sodium on the kidneys were studied during 4 1/2 hours in eight patients with normal renal function. Urinary output decreased within 10 min after the injection, and maximally by 80%. The renal plasma flow and the glomerular filtration rate initially diminished significantly, by 35%, but began to increase after only 2 hours. The dominant and persistent effect was a reduction of free water clearance, with maximum fall from 5.9 to 0.08ml/min after 2 1/2 hours. Aim: The aim of this study was to evaluate the effects of diclofenac-induced acute nephrotoxicity using biochemical parameters in rats.Methods: 12 male Wistar rats allotted in 4 equal groups were intraperitoneally injected with 0, 10, 50 and 100mg/kg diclofenac, respectively and 12 hours after injection, blood serum samples were collected for assessment of basic renal function test parameters such as urea, creatinine, and uric acid, sodium, Potassium.Results: Rats treated up to 50mg/kg diclofenac were considered to be within normal range in rats. By increase in dose more than 50mg/kg showed significant increases in uremia were evidenced in intoxicated animals. Observed specifically in group IV Rats.Conclusions: In this study, uremia, as an indicator of kidney damage, was significantly increased depending on dose. Diclofenac may cause kidney damage depending on dose and this effect may also be observed. NSAIDs-induced nephrotoxicity may be due to the inhibitory effect of these drugs on prostaglandin synthesis, thus causing kidney ischemia.

Using DNA Barcodes to Evaluate Ecosystem Health in the SWRCMS Reserve

The Western Center Academy (WCA) Charter School and Mt. San Jacinto College (MSJC) are located on the Southwestern Riverside County Multi-Species Reserve (SWRCMSR). Developed in 1992, the reserve is home to at least 8 sensitive bird, animal, and plant species. Although the reserve is protected against direct human influence, within a 100-mile circle of SWRCMSR live more than 21 million people with their indirect impact on the environment. Our goal was to determine if the reserve is protecting the species within by analyzing the genetics of those species to determine if there is a healthy amount of genetic diversity in the populations within. We collected insects at MSJC Menifee campus and in the SWRCMSR to evaluate how human impact affects the genetic diversity of insects. MSJC served as the site that was impacted by human activities and SWRCMSR served as the site that was not impacted by human activities. The School Malaise Trap Project (SMTP) selected 160 of our specimens, sequenced their genetic barcodes, and entered the data into the Barcode of Life Database (BOLD) for analysis. Using the BOLD website and a Clustal Omega tool, we compared the genetic sequences in the insects we collected to measure genetic differences in the two populations of insects. The results from the two collections seem to show that the nature reserve insect population is a younger population with genetic changes possibly acquired by gene flow from immigration. The insect population at MSJC appears to be well developed, but isolated genetically.

Zebrafish Sensitivity to Botulinum Neurotoxins.

Botulinum neurotoxins (BoNT) are the most potent known toxins. The mouse LD50 assay is the gold standard for testing BoNT potency, but is not sensitive enough to detect the extremely low levels of neurotoxin that may be present in the serum of sensitive animal species that are showing the effects of BoNT toxicity, such as channel catfish affected by visceral toxicosis of catfish. Since zebrafish are an important animal model for diverse biomedical and basic research, they are readily available and have defined genetic lines that facilitate reproducibility. This makes them attractive for use as an alternative bioassay organism. The utility of zebrafish as a bioassay model organism for BoNT was investigated. The 96 h median immobilizing doses of BoNT/A, BoNT/C, BoNT/E, and BoNT/F for adult male Tübingen strain zebrafish (0.32 g mean weight) at 25 °C were 16.31, 124.6, 4.7, and 0.61 picograms (pg)/fish, respectively. These findings support the use of the zebrafish-based bioassays for evaluating the presence of BoNT/A, BoNT/E, and BoNT/F. Evaluating the basis of the relatively high resistance of zebrafish to BoNT/C and the extreme sensitivity to BoNT/F may reveal unique functional patterns to the action of these neurotoxins.

Estudo sobre a sensibilidade dos caprinos à toxidez de crotalárias tóxicas para bovinos visando a sua utilização na profilaxia

Resumo: A intoxicação por plantas é sabidamente uma das principais causas de morte de bovinos adultos no Brasil. Uma vez que pouco pode ser feito no que diz respeito ao tratamento destas intoxicações, os esforços devem se concentrar na adoção de medidas profiláticas alternativas, como a utilização de uma espécie menos sensível no local de ocorrência de determinadas plantas. Objetivou-se com esse trabalho verificar a sensibilidade de caprinos às crotalárias (Crotalaria spectabilis e Crotalaria juncea) para que estes possam ser utilizados na profilaxia da intoxicação por essas plantas em bovinos. Sementes de C. spectabilis e C. juncea foram fornecidas em doses únicas ou diárias a oito caprinos adultos jovens, de ambos os sexos, divididos aleatoriamente em dois grupos de quatro animais (um grupo para cada planta). Dos quatro caprinos que receberam as sementes de C. juncea, nenhum desenvolveu sinais clínicos de intoxicação ou apresentou alterações significativas no exame bioquímico. Entre os quatro caprinos que receberam sementes de C. spectabilis três morreram. Um animal recebeu uma dose única de 20g/kg de sementes da planta e desenvolveu sinais de intoxicação aguda, caracterizadas macro e microscopicamente por necrose hemorrágica centrolobular. Os outros dois caprinos desenvolveram um quadro de intoxicação crônica pela administração de doses diárias de 2g/kg de sementes da planta por 35 e 150 dias respectivamente. Um animal apresentou uma marcada pneumonia intersticial e lesões hepáticas leves, enquanto no outro caprino observaram-se apenas lesões hepáticas crônicas. Ambos os animais apresentaram alterações transitórias ao exame bioquímico. O quarto caprino recebeu a dose única de 10g/kg, sobreviveu e não apresentou alterações clínicas ou da bioquímica sanguínea significativas. Os resultados do trabalho mostraram que não se deve usar caprinos como medida profilática na intoxicação por C. spectabilis,mas que pode se recomendar esta espécie na profilaxia da intoxicação por C. juncea.

Induction of autophagy in human neuroblastoma SH-SY5Y cells by tri-ortho-cresyl phosphate.

Tri-ortho-cresyl phosphate (TOCP) is an organophosphorus ester and has been widely used in industry. It is found that TOCP induced delayed neurotoxicity in humans and sensitive animal species. However, the mechanism of TOCP-induced neural cytotoxicity remains unclear. In this study, we studied whether autophagy is involved in TOCP-induced neural cytotoxicity in human neuroblastoma SH-SY5Y cells. We found that 0.5 and 1.0 mM TOCP treatment significantly increased the ectopic accumulation of microtubule-associated protein 1 light chain 3 (LC3)-immunopositive puncta, Beclin 1, and LC3-II/LC3-I levels in SH-SY5Y cells in a dose-dependent manner. Notably, by monodansylcadaverine staining method, we found abundant punctate fluorescent acidic vesicular organelles in TOCP-treated cells. Furthermore, ultrastructural observation under the transmission electron microscope indicated that the cytoplasm was occupied by autophagosomes in TOCP-treated SH-SY5Y cells. Thus, these results suggest that TOCP may induce autophagy, and autophagy may be involved in the development of TOCP-induced neural cytotoxicity.

Artificial sweeteners

Low-calorie sweeteners are authorised food additives in the European Union (EU). The safety of these sweeteners has been evaluated in accordance with internationally agreed principles for the safety evaluation of food additives. In the EU, the European Commission’s Scientific Committee for Food (SCF) was the scientific guarantor for the safety of food additives until March 2003. Since then this has been taken over by the European Food Safety Authority (EFSA), notably its Scientific Panel on Food Additives and Nutrient Sources Added to Food (ANS Panel). Based on the large number of toxicological studies that are requested for the safety evaluation of food additives, a no observed adverse effect level (NOAEL) is identified for the most sensitive effect in the most sensitive animal species. A safety factor of 100 is normally applied to the NOAEL in order to establish an acceptable daily intake (ADI) for humans. The ADI is the amount of the food additive, expressed on a milligram per kilogram of body weight (bw) basis, that can be ingested daily over a lifetime without any appreciable health risk. The following low-calorie sweeteners have been allocated an ADI by either the SCF or EFSA: acesulfame K, aspartame, cyclamates, neotame, saccharin, steviol glycosides and sucralose.

Validation of the phase 0 concept.

TPS143 Background: Over 90% of drugs entering Phase I trials eventually fail, however, it is not currently possible to predict failure prior to undergoing costly and lengthy clinical trials. In response, the FDA proposed an “exploratory IND” (investigational new drug), a novel clinical trial design commonly referred to as “Phase 0”, aimed at accelerating the critical path of drug development. Phase 0 trials expose a small number of patients to a single “microdose” (starting at 1/50th of the no observed adverse effect level, NOAEL, from the most sensitive animal species) of an experimental drug with the goal of validating pre-clinical models to aid in the ‘go/no-go’ decision of drug development. The ultimate goal is to allow Phase 0 effective drugs to enter combination studies earlier, and Phase 0 ineffective drugs to avoid further costly development (Kummar S, Nat Rev Cancer 7:131-139, 2007). We are concerned that potentially effective drugs or classes of drugs may be discarded based on a microdosing concept which has not been effectively validated in human subjects. To our knowledge, the Phase 0 dosing concept has not been evaluated using a known effective agent. Our hypothesis is that a microdose may not be an accurate surrogate for standard doses, and thus, a Phase 0 trial may yield false negative results. We are now conducting a Phase 0 trial evaluating the effects of microdoses of an FDA-approved drug, temsirolimus, on its known pharmacodynamic (PD) targets. The primary endpoint is PD target modulation. Methods: Patients with advanced cancer, preferably with tumor available for biopsy, >5 half lives removed from previous therapy, and being screened for Phase I trials involving temsirolimus will be eligible (n = maximum 15). The exclusion criteria are pregnancy or lactation, <18 years of age, bleeding diathesis, or hypersensitivity to temsirolimus. Temsirolimus will be administered once, with a starting dose level of 0.02 mg (~1/50th NOAEL). PD markers will be assessed in PBMCs before and after dosing. Phase 0 patients who subsequently enroll on a temsirolimus-containing Phase I trial will have the same PD markers assessed to compare drug effect of Phase 0 and Phase I doses. The trial was activated in November 2010, currently has enrolled 4 patients, and is supported in part by 2K12CA088084-11.

Toxic effects induced by mycotoxin fumonisin B1 on equine spermatozoa: Assessment of viability, sperm chromatin structure stability, ROS production and motility

Fumonisin B1 (FB1) is a mycotoxin produced by Fusarium species that exerts its toxic effect through interference with the sphingolipid pathway by inhibiting ceramide synthase. A FB1-dependent sperm toxicity was reported in boars. No information on FB1-related reproductive toxicity in stallions, the most sensitive animal species, has been reported. The aim of the present study was to assess the in vitro toxicity of FB1 on fresh and frozen-thawed equine spermatozoa by analyzing sperm viability, chromatin stability (SCSA) and reactive oxygen species (ROS) production by flow cytometry and sperm motility by CASA system. Fumonisin B1 did not affect viability of fresh spermatozoa after 2 h exposure up to 25 μM. Damage on sperm chromatin structure was observed only in one frozen sample after exposure up to 2.5 × 10 −5 μM FB1 without associated increase of ROS. Increase of ROS, at FB1 levels up to 2.5 × 10 −4 μM, was found on another frozen-thawed sperm sample, may be as a consequence of seminal plasma removal. At 7.5 and 15 μM, FB1 induced reduction of total and progressive motility.

Porcine oocytes are most vulnerable to the mycotoxin deoxynivalenol during formation of the meiotic spindle

Deoxynivalenol (DON, vomitoxin) is a secondary metabolite and mycotoxin produced by Fusarium species that occurs with a high prevalence in cereals and grains intended for human and animal consumption. Pigs are considered to be the most sensitive animal species and exposure to DON results in reduced feed intake, reduced performance and cause alterations in the expression of markers of inflammation and cell cycle regulation. The objective of this study was to determine how DON possibly affects the oocyte developmental potential in vitro at concentrations which correspond to those observed in practice. To evaluate DON toxicity during specific stages of oocyte meiosis, cumulus-oocyte complexes were exposed to 0.02, 0.2, or 2 μM DON. Exposure to the highest DON concentration inhibited cumulus expansion and induced cumulus cell death. After exposure for 42 h, DON at all concentrations reduced Metaphase II formation and led to malformations of the meiotic spindle. Despite spindle malformations, exposure to different concentrations of DON did not lead to increased percentages of blastomeres with abnormal ploidy in embryos. Spindle malformation occurred by DON exposure during formation of meiotic spindles at Metaphase I and II, but embryo development was also reduced when oocytes were exposed to DON during Prophase I. Together, these results indicate that exposure to DON via contaminated food or feed can affect oocyte developmental competence by interfering directly with microtubule dynamics during meiosis, and by disturbing oocyte cytoplasmic maturation through other as yet undetermined mechanisms.

Successful drug development despite adverse preclinical findings part 1: processes to address issues and most important findings.

Unexpected adverse preclinical findings (APFs) are not infrequently encountered during drug development. Such APFs can be functional disturbances such as QT prolongation, morphological toxicity or carcinogenicity. The latter is of particular concern in conjunction with equivocal genotoxicity results. The toxicologic pathologist plays an important role in recognizing these effects, in helping to characterize them, to evaluate their risk for man, and in proposing measures to mitigate the risk particularly in early clinical trials. A careful scientific evaluation is crucial while termination of the development of a potentially useful drug must be avoided. This first part of the review discusses processes to address unexpected APFs and provides an overview over typical APFs in particular classes of drugs. If the mode of action (MoA) by which a drug candidate produces an APF is known, this supports evaluation of its relevance for humans. Tailor-made mechanistic studies, when needed, must be planned carefully to test one or several hypotheses regarding the potential MoA and to provide further data for risk evaluation. Safety considerations are based on exposure at no-observed-adverse-effect levels (NOAEL) of the most sensitive and relevant animal species and guide dose escalation in clinical trials. The availability of early markers of toxicity for monitoring of humans adds further safety to clinical studies. Risk evaluation is concluded by a weight of evidence analysis (WoE) with an array of parameters including drug use, medical need and alternatives on the market. In the second part of this review relevant examples of APFs will be discussed in more detail.

Growth inhibition and induction of G 1 phase cell cycle arrest in neuroblastoma SH-SY5Y cell by tri- ortho-cresyl phosphate

It has been known that tri- ortho-cresyl phosphate (TOCP) can induce delayed neurotoxicity in humans and sensitive animal species; however, it also has influence on the developing central nervous system or differentiating neuronal cells. In this study, the effects of TOCP on cell proliferation and cell cycle regulation and the mechanisms that contribute to this effect were investigated by using human neuroblastoma SH-SY5Y cell line. Treatment of the cells with TOCP suppressed cell proliferation and reduced cell viability in a dose- and time-dependent manner. Analysis of cell cycle profile indicated that TOCP blocked cell cycle progression by arresting the cell cycle at G 1 phase. The data of determination of cell cycle regulated molecules at mRNA and protein levels showed that TOCP decreased cyclin D1 and increased p21 expression, while did not affect the p53 and p27 levels. Thus, these results indicated that TOCP might induce potential neurodevelopmental toxicity, and a possible mechanism of this toxicity might be the disturbance of cell proliferation by disrupting cell cycle regulatory proteins cyclin D1 and p21 expression.