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Background/Aims: Kynurenic acid (KYNA), a tryptophan metabolite along the kynurenine pathway, is an endogenous antagonist of glutamate ionotropic excitatory amino acid (EAA) receptors and the a7 nicotinic acetylcholine receptor (nAChR). The involvement of KYNA in various pathological conditions and during the aging process is significant. KYNA synthesis from L-kynurenine (L-KYN), through the action of several kynurenine aminotransferases (KATs), is present in the central nervous system (CNS) and periphery of mammals. We were interested in investigating the ability of the brain and peripheral organs of Helix pomatia snails to synthesize KYNA, in an in vitro study. In comparative studies between rat and snail, we looked for the synthesis of KYNA in the liver. We then looked for an effect of age on KYNA synthesis. Materials: Ten shell parameters of the Helix pomatia snail were used to establish an Age Rating Scale (ARS), i.e. body weight, shell weight, shell length, width and height, shell opening length and width, lip width, number of shell turns and external shell growth rings. An age of the snails was determined according to the ARS and the snails were divided into three groups, i.e. young, middle and old age. Homogenates of dissected regions, i.e. cerebral ganglia (CG), subpharyngeal ganglia (SG) consisting of pedal, visceral and pleural ganglia, heart and liver, were examined. KYNA was measured by high performance liquid chromatography (HPLC) and KAT activities were measured by an enzymatic method. Results: With respect to ARS, an evaluation of the age of the snails between young (1-2 years), middle (5-7 years) and old (9-13 years) showed significant differences (p<0.001). Analysis of KYNA levels in different snail tissues, i.e. CG, SG, heart and liver, showed an occurrence in the low femtomolar range. Marked and significant increases of KYNA were found in the liver of middle and old age groups. In the SG, KYNA decreased significantly with age. There were no differences in KYNA levels between groups in CG and heart. The lowest KAT activity was found in CG and SG (5 pmol/mg/h), while in heart and liver the values were visibly higher (between 8 and 80 pmol/mg/h). Only in the liver, and exceptionally only for KAT I, the activity increased significantly with age, i.e. up to 14 years. No age-related changes in KAT I, II and III activities were found in CG and SG. Snail liver shows a different pattern of KAT activities compared to the rat liver. Conclusion: Regions of the CNS and periphery of the snail Helix pomatia are able to synthesize KYNA due to KAT activities. In the snail liver, KAT I activity increased with age. Notably, there was no age-related increase in KAT activities in the heart and especially in the CNS of Helix pomatia, indicating significant differences from mammals. A moderate KYNA metabolism in the Helix pomatia snail in the periods studied, up to 14 years, could be a physiological phenomenon that protects organs from possible functional insufficiency due to high KYNA levels, as has been suggested. It is reasonable to search for the factor(s) that could regulate the concentration of KYNA in the body of the snail. [ABSTRACT FROM AUTHOR]

The food preferences and palatability of different plant species for snail and slug species in arable fields has been a major area of research in the past. The assumed diet of Helix pomatia (Linnaeus, 1758), however, provides an example of the limited knowledge of snail diets in nonagricultural habitats. This species has been described as a generalist herbivore, although it showed preferences for individual plant species in another study. Helix pomatia is considered a pest species, while also being listed as endangered in several Red Lists. In this study, the feeding activity of eight subpopulations of H. pomatia were recorded in a nature reserve in Cottbus, Germany, from April to October 2021 to understand food preferences and feeding behaviour. Along with the plant species on which feeding was observed, the height of feeding in the vegetation, shell width and height, number of whorls, and exposure to direct sunlight at observation sites were recorded. Results indicate that H. pomatia prefers Urtica dioica, and plant litter, which accounted for 35% and 44% of all observed feeding interactions respectively, as food resources, while generally only feeding on 27 of 143 available plant species. The importance of U. dioica as a food resource for 19 other terrestrial snail species is confirmed by 18 previous studies. In H. pomatia, analysis of the width and height of shells indicated that smaller, juvenile snails consumed plant material significantly higher up in vegetation as compared to adult snails, which fed closer to the ground. Awareness of the preference in H. pomatia for U. dioica as a food resource may be beneficial for land managers regarding the impact of this snail as an agriculture pest to crops. Urtica dioica is a very important food plant for terrestrial snails, and could play an important role in future species conservation strategies. [ABSTRACT FROM AUTHOR]

Aim: Were postglacial recolonizations facilitated by persistence close to the colonized areas rather than by dispersal ability allowing for colonization from distant sources? This question is particularly relevant for organisms with low active dispersal abilities and lacking specialized propagules. Here we identified glacial refugia of four Central European land snail species, including one for which a northern glacial refugium in the region was indicated by indirectly dated fossils. Location: Central Europe and the Balkans. Taxon: Pulmonate land snails: Monachoides incarnatus (Hygromiidae) and Helix pomatia, Helix thessalica and Caucasotachea vindobonensis (Helicidae). Methods: We used continuous phylogeographic analysis of mitochondrial sequence data to trace the origin of postglacially expanding lineages. We assessed the credibility of results from our focal species, M. incarnatus, by comparison to three other broadly sympatric land snail species. In addition, we performed direct radiocarbon dating of fossil shells to verify the presumed glacial presence of M. incarnatus on the territories of Czechia and Slovakia and to test the reliability of the available fossil data. Results: In three of the four species, the molecular data supported refugia located south of the Pannonian Basin, from the south‐eastern Alps to the south‐western Carpathians, but not more northerly. The direct radiocarbon dating resulted in younger dates than previously assumed. However, the molecular data also revealed unexpected, yet substantial postglacial southward expansions of M. incarnatus and C. vindobonensis into the Balkans. Main Conclusions: Neither the phylogeographic analyses nor the direct radiocarbon dating provided evidence for the glacial survival of studied land snail species in Central Europe. The refugia located adjacent to the Pannonian Basin were the most important source of postglacial expansions to Central Europe, but were also the source of the expansion southwards. Both climatic factors and biological interactions might explain why such southward expansions seem rather rare in Europe. [ABSTRACT FROM AUTHOR]

Atmospheric pollution remains one of the growing concerns in the twenty-first century, with particular focus on metal trace elements (MTE) from anthropogenic sources, due to their adverse effects on biota. The concentration and type of MTE in the atmosphere and in the soil are diverse, depending on the origin of pollutants, which can cause diverse detrimental effects on organisms living in the nearby environment. Three sites in Central Serbia with different origins of MTE pollution (urban contamination, smelting, and fly ash area) were assessed, using terrestrial Roman snails (Helix pomatia) as biomarker organisms. These snails are sentinel organisms and are known for their capacities for accumulation of MTE. Snails were sampled and their body was divided in three parts: viscera, foot, and shell and concentrations of MTE were determined in each of these body parts using inductively coupled plasma optical spectrometry. Results showed contrasting MTE accumulation patterns in body parts of the snails. Of three studied sites, snails sampled in the vicinity of fly ash containment had lower concentrations of MTE compared to other two polluted sites. [ABSTRACT FROM AUTHOR]

Phasmarhabditis papillosa is a promising biocontrol agent of gastropods in crops. To enhance the efficacy of mollusc parasitic nematodes, a better understanding of the chemical signalling between hosts and parasites is needed. The objective of this research was to test the stimulus–response behaviour of the mollusc parasitic nematode P. papillosa towards mucus of the following mollusc species: Arion vulgaris, Limax maximus, Deroceras reticulatum, and Helix pomatia. The nematode chemotactic response was observed as directed motility towards mucus of the tested mollusc species at two temperature regimes under laboratory conditions. The motility of P. papillosa was more strongly expressed at a higher temperature (20 °C) than at a lower temperature (15 °C). When comparing mucus of different mollusc species, none of the tested molluscs significantly affected the directed motility of P. papillosa at the lower temperature (15 °C). At the higher temperature (20 °C), mucus samples from L. maximus and H. pomatia were observed to be more attractive than those from A. vulgaris or D. reticulatum for the nematodes. Our results indicate that P. papillosa distinguishes among mollusc species by exhibiting a chemotactic response to a signal emanating from mollusc mucus. [ABSTRACT FROM AUTHOR]

Our purpose was to monitor the environmental pollution with heavy metals, such as Pb, Zn, Cu, and Cd, and their accumulation in Roman snails (Helix pomatia L.) and the possibility of Roman using snail as a bioindicator of heavy metal pollution. For analyses, we were taken 22 specimens of roman snails in the Mitrovica town (area with the heavy metal pollution derived from the "Trepça" smelter) and 22 specimens in the Vernica village (control area), in which case is analyzed the concentration of heavy metals: Lead (Pb), cadmium (Cd), Zinc (Zn) and Copper (Cu) in the hepatopancreas, foot, and shell of snails. Our results show the high concentration of Pb, Zn, and Cd in the hepatopancreas compared to the other tissues (foot and shell), whereas Cu concentration was higher in the foot of snails from Mitrovica compared to the control group in a significant degree (P < 0.001). We have found a significant (P<0.001) positive correlation between all heavy metals (Pb/Cd; Pb/Cu; Pb/Zn; Cd/Cu; Cd/Zn and Cu/Zn) in the hepatopancreas tissue. In the foot, we have found the negative correlation for Pb/Cd and Pb/Cu and positive for the Pb/Zn; Cd/Cu; Cd/Zn, and Cu/Zn, whereas in the shell the correlation was positive for the Pb/ Cd; Pb/Cu and Cd/Cu, and negative for the Pb/Zn; Cd/Zn and Cu/Zn. In the hepatopancreas, the concentration of metals ranged from higher to the lower concentration was: Zn>Cd>Pb>Cu; in the foot: Cu>Zn>Cd>Pb, whereas in the shell: Zn>Cu>Pb>Cd. The Mitrovica town is the area with heavy metals pollution, whereas the Roman snail accumulates relatively high values of these heavy metals and can serve as an indicator organism for pollution with the metals such as Pb, Cd, Zn, and Cu. [ABSTRACT FROM AUTHOR]

Epilepsy is a neurological disorder characterized by a hyperexcitable state in neurons from different brain regions. Much is unknown about epilepsy and seizures development, depicting a growing field of research. Animal models have provided important clues about the underlying mechanisms of seizure-generating neuronal circuits. Mammalian complexity still makes it difficult to define some principles of nervous system function, and non-mammalian models have played pivotal roles depending on the research question at hand. Mollusks and the Helix land snail have been used to study epileptic-like behavior in neurons. Neurons from these organisms confer advantages as single-cell identification, isolation, and culture, either as single cells or as physiological relevant monosynaptic or polysynaptic circuits, together with amenability to different protocols and treatments. This review's purpose consists in presenting relevant papers in order to gain a better understanding of Helix neurons, their characteristics, uses, and capabilities for studying the fundamental mechanisms of epileptic disorders and their treatment, to facilitate their more expansive use in epilepsy research. [ABSTRACT FROM AUTHOR]

Shells of molluscs from snail farms (heliciculture) are used as food additives or construction material and ecological engineering approaches utilize their potential to assist with ecosystem restoration. Previous studies, for example, highlighted the importance of snail shells as microhabitat for threatened arthropod species with particular focus on wild bees nesting in empty shells. This study focuses on shells of the Roman snail (Helix pomatia Linnaeus, 1758) and their value as microhabitat for shell adopters in different dominant vegetation forms and sample periods. In total, 1408 empty shells were placed in areas dominated by one of two vegetation forms (herbaceous vegetation or trees) from February to November 2019 (autumn) or from February to June/July 2020 (summer). All collected shells (N = 618) were sealed at the time of collection, frozen and all content was then analysed with a digital microscope. In total, 91.4 % of all collected shells were occupied and the average number of shell adopters was 1.5 time higher in shells collected in summer compared to shells collected in autumn. The number of shell adopters per shell was 1.5 times higher in study areas dominated by herbaceous vegetation compared to study areas dominated by trees. Shell width, but not shell height significantly affected the composition of shell adopter communities. Shells with a larger width were more frequently colonized by another gastropod species [Discus rotundatus (O. F. Müller, 1774)] than less wide shells. Shells of the Roman snail provide important multipurpose benefits for a wide range of soil organisms, particularly in habitats that were dominated by herbaceous vegetation and in summer. In autumn, shell adopters included isopods, gastropods and spiders in one subset of shells or Collembola in another subset. The future use of commercially available, empty shells from heliciculture in local restoration projects of open, tree-free areas, holds the potential to support a diverse invertebrate fauna with additional refuge habitats.

The aim of this study was to compare the quality of clutches and reproduction results of two groups of Roman snails (Helix pomatia) from the same local population, laying eggs simultaneously in semi-natural farm conditions and in a natural habitat. The study material were Roman snails aged 2 or more years which had entered the third phenological season of their life and thus the first season of sexual maturity. Observations were conducted at an earthen enclosure in a greenhouse belonging to the experimental farm for edible snails at the National Research Institute of Animal Reproduction in Balice near Kraków (Poland) as well as at a site where a local population naturally occurs in the uncultivated park surrounding the Radziwiłł Palace. In the June-July season, differences among such parameters as weight of clutch, number of eggs in clutch, mean egg weight, and hatchling percentage when compared to the total number of eggs in the clutch were compared. It was determined that clutches of eggs from the natural population laid in the greenhouse were of lesser weight (P<0.01), contained fewer eggs (P<0.05), and the mean weight of individual eggs was less (P<0.05) than in clutches laid simultaneously in a natural habitat. Both in the greenhouse and the natural habitat, in the first phase of laying eggs (June) the weight of the clutch and number of eggs its contained were greater than in the second phase (July). However, only for snails laying eggs in the greenhouse were these differences statistically significant (P<0.05) and highly significant (P<0.01), respectively. Statistically significant differences were not observed in hatchling percentage between eggs laid in the greenhouse and the natural habitat. The lower number of eggs laid in the farmed conditions of the greenhouse was successfully compensated for by the absence of mass destruction by rodents which occurred in the natural habitat. [ABSTRACT FROM AUTHOR]

Introduction: The objective of the present research was to carry out a comparative assessment of copper, zinc, and selenium concentrations in the meat of edible land snails collected in Poland (Helix pomatia, Cornu aspersum maxima, and Cornu aspersum aspersum), as well as to determine the effect of preliminary processing of Roman snails (Helix pomatia) on the content of the aforementioned elements. Material and Methods: In the first stage, determinations were made on unprocessed snail meat. In the second stage, the study focused on Roman snails and consisted in an additional evaluation of frozen meat after full processing. Zinc and copper contents were determined by flame atomic absorption spectrometry and the selenium content was established by graphite furnace atomic absorption spectrometry. Results: The selenium content differed significantly among all three species. The copper content in Roman snails differed significantly from that in farmed snails. No significant difference in the zinc level was noted among the three snail species. The selenium content in raw and processed meat of Roman snails did not show any significant difference while the copper and zinc level was significantly higher in processed meat samples. Conclusion: The present research on the meat of edible snails showed different levels of selenium, copper, and zinc, depending on the species, collection site, and subjection to processing.

The aim of the study was to improve and determine the degree of freshness of meat of snails of Helix genus after different technological processing by bacterioscopic method. Since there is no data in the modern scientific literature about the determination of indicators of safety and quality of meat of snails, in particular the freshness of meat of different species and different technological processes by bacterioscopic method, therefore the problem is relevant. The meat of snails of genus Helix has been used for the study, subspecies: Helix pomatia, Helix aspersa maxima and Helix aspersa muller. 30 samples of meat of snails of each species, bred in a snail farm of the Kyiv region were selected for the study. The research was conducted in the winter, when the snails were in anabiosis condition. The meat of snails was investigated after various technological processing: live, chilled and cooked and frozen. According to the results of the study, it was found that the meat of live snails was fresh for 2 days; doubtful freshness - from 3 days to 5 days; stale - in 7 days; freshly chilled meat of snails was fresh in 2 days including; doubtful freshness - from 3 to 6 days; stale - in 7 and 8 days; and cooked and chilled snails' meat was fresh after the storage for 6 months at a temperature of minus 18 °C. These data are stable and reliable, therefore, these indicators can be used in assessing the safety of snail meat under different processing conditions and after different storage periods. [ABSTRACT FROM AUTHOR]

The total number of hemocytes and their morphological characteristics were analyzed in Helix pomatia Linnaeus, 1758, by light microscopy during different phases of hibernation. Three types of hemocytes were identified: hyalinocytes, agranulocytes, and granulocytes. Total number of hemocytes decreased significantly during hibernation. Most intensive changes in cell size, morphology, and appearance of special structures in granulocytes happened during the hibernation period itself. Termination of hibernation coincides with very important granulocyte transformation and the appearance of specific gigantic short-lived cells. All of the changes in cell number and morphology are characteristics of different hibernation phases and have a major role in adaptive hypothermia. Granulocytes are hemocytes of great importance in immune response while specific functions of hyalinocytes and agranulocytes remain largely unexplored. [ABSTRACT FROM AUTHOR]

Populations of Roman Snail, Helix pomatia, a large European land snail, are reported for the first time in Canada from disturbed habitats in two distant locations: Sarnia, Ontario and Montrose, British Columbia. As Roman Snail is an edible species subject to international commercial trade, its deliberate, but illegal, introduction into Canada and intentional or unintentional releases are possible sources of these populations. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Sulfatases hydrolyze sulfated metabolites to their corresponding alcohols and are present in all domains of life. These enzymes have found major application in metabolic investigation of drugs, doping control analysis and recently in metabolomics. Interest in sulfatases has increased due to a link between metabolic processes involving sulfated metabolites and pathophysiological conditions in humans. Herein, we present the first comprehensive substrate specificity and kinetic analysis of the most commonly used arylsulfatase extracted from the snail Helix pomatia. In the past, this enzyme has been used in the form of a crude mixture of enzymes, however, recently we have purified this sulfatase for a new application in metabolomics-driven discovery of sulfated metabolites. To evaluate the substrate specificity of this promiscuous sulfatase, we have synthesized a series of new sulfated metabolites of diverse structure and employed a mass spectrometric assay for kinetic substrate hydrolysis evaluation. Our analysis of the purified enzyme revealed that the sulfatase has a strong preference for metabolites with a bi- or tricyclic aromatic scaffold and to a lesser extent for monocyclic aromatic phenols. This metabolite library and mass spectrometric method can be applied for the characterization of other sulfatases from humans and gut microbiota to investigate their involvement in disease development. [ABSTRACT FROM AUTHOR]

The aim of this work was to analyse the effect of incubation HPA (lectin Helix pomatia agglutinin) with ID (insemination dose) on reproduction parameters (conception ratio, number of live and dead born of pups and birth weight of pups) of rabbits. The experiments were carried out under conditions of 2 rabbit breeds (production breed P and experimental breed E). Fresh ID, in sperm concentrations 25 mil. / 0.5 ml ID, were divided into control ID (without HPA) and experimental ID (with HPA). HPA was added to the experimental ID in concentrations 1μg HPA / 1x106 spermatozoa (30 - 60 minutes of incubation before AI - artificial insemination). Conception ratios obtained from 2 different breeds (P, E) showed minor improvement (+ 2.67 % P; + 7.36 % E) between the monitored groups of females, however without statistically significant differences (P χ2 = 0.03; E χ2 = 0.11). Number of live born pups in litter obtained from breeds P and E showed minor improvement (+ 0.37 pcs P (p>0.05); + 0.95 pcs E (p≤0.05)) compared to the control groups. The weight of live pups among the monitored groups was comparable. It can be concluded from the present study that incubation of ID with lectin HPA had been positively affected by the observed reproductive parameters. The statistically significant difference was found only in the number of live-born pups in the litter. The price of lectin is too high for breeding in common breeding practice. [ABSTRACT FROM AUTHOR]

Introduction: The objective was to determine the content of fatty acids in edible snail fat by snail species, collection site, and processing stage. Material and Methods: The research material comprised 180 edible fat samples from the three genera of edible snails collected in Poland: free-living Helix pomatia (HP) and two cultivated Cornu subspecies: C. aspersa maxima (CAM) and C. aspersum aspersum (CAA). All snails came from the Greater Poland and Lower Silesian Provinces: HP from their natural habitat and CAM and CAA from heliciculture farms. The studies focused on the raw meat, cooked meat, and frozen meat processing stages. Fatty acid (FA) profiles were determined by the gas chromatography method. Results:Helix pomatia fat showed a higher saturated fatty acid (SFA) content, whereas the fat of Cornu genus snails had a higher unsaturated fatty acid (UFA) component, i.e. monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA). Thermal processing of snail meat increased all the determined SFA and decreased all the PUFA values, and increased the content of C18:1, C20:1, and C22:1 acids in the MUFA group. The material collection site had limited impact on FA content as differences were noted only in levels of C18:1, C18:2 n6, and C20:5. The differences pertained only to the fat of farmed snails of the Cornu genus. Conclusion: Due to the high content of UFA and a favourable ratio of n6:n3 acids and PUFA:SFA, snail fat can be regarded as nutritionally valuable. [ABSTRACT FROM AUTHOR]

Цель исследования – изучение восприимчивости моллюсков вида Helix pomatia к протостронгилидам при многократном заражении. Материалы и методы. Экспериментальное заражение моллюсков вида H. pomatia (Mollusca, Helicidae) протостронгилидами (Nematoda: Protostrongylidae) осуществляли последовательно 4 раза через каждые 14–20 сут. Через 2 недели после каждого очередного заражения часть моллюсков вскрывали с целью определения экстенсивности и интенсивности инвазии (ИИ), коэффициента внедрения личинок в моллюсков, стадии развития в моллюсках. Личинок протостронгилид получали из ноги моллюска, которую отсекали и исследовали под микроскопом компрессорным методом. Полученные результаты обработали статистически, используя программу Statistica 7. Результаты и обсуждение. Выявлено, что после каждого нового заражения ИИ и коэффициент внедрения повышаются. Данные исследований показали, что моллюски остаются восприимчивыми к инвазии протостронгилидами в условиях многократного заражения. После 3 и 4-го заражений относительное число внедрившихся в моллюсков личинок меньше, по сравнению с 1 и 2-м инвазированием. Это означает, что у хозяина существуют механизмы, ограничивающие увеличение интенсивности инвазии протостронгилидами в условиях повторяющихся заражений.

European snail Helix pomatia Linnaeus, 1758 has been widely introduced in Central Russia. The history of the introduction and review of the recent distribution of the species are presented. Possible ways of the introduction of this species are discussed.

The aim of this study was to evaluate the differences between concentrations of heavy metals (cadmium, copper, zinc, iron, and manganese) in terrestrial gastropods, Helix pomatia, collected in four different environment locations in Pančevo city, Serbia. Metal concentrations in the foot and in the digestive gland were measured. Heavy metals cadmium, copper, zinc, iron, and manganese were measured in triplicate by atomic absorption spectrophotometry. Also, this study investigated correlations between the trace element content in the soft tissues and different seasons (summer and fall). The results showed that heavy metal concentrations of the measured elements in both snail tissues were significantly higher in polluted sites when compared to the background levels in the city. In digestive gland tissues, the concentration of heavy metals was higher compared with that in foot tissues. The bioaccumulation (heavy metal concentrations in soft tissues) of heavy metals (Cd, Cu, Zn, Fe, and Mn) in snails, Helix pomatia, has been assessed and related to seasons and sites. Heavy metal accumulation in the soft tissues of snails could provide a powerful monitoring tool for the assessment of environmental heavy metal pollution. [ABSTRACT FROM AUTHOR]

Total number and types of hemocytes were analysed in hemolymph of Roman snail (Helix pomatia L.). Significant differences in the number and types of hemocytes during the season at different locations were identified. The average number of hemocytes ranged from 154 to 288 per 10 μL of hemolymph. The highest number of hemocytes was recorded in snails at higher altitudes. Significant intergroup differences between all sites were identified. The most numerous hemocytes were granulocytes, followed by agranulocytes, while hyalinocytes were the least common in the post-hibernation period. Post hoc analysis showed certain intragroup differences for most locations except for comparison between wet habitat and habitats with anthropogenic influence, and between wet habitats and urban place with wet vegetation. A large number of transformed hemocytes in the encapsulated phase were identified in snail hemolymph infected with flat worms. Our results represent the first record of data for the number of hemocytes in molluscs and the first data for hemocytes of Helix pomatia. Further investigations and development of a uniform classification of hemocytes and their role in the immune response would be necessary in the future. [ABSTRACT FROM AUTHOR]

The work is a continuation of two previous studies in which biomarker fatty acids (12 of 56 FA pools) were analysed in Helix pomatia L. after heterogeneous micro-supplementation of Zn and Cu (administered in five micro-doses in the form of salts and EDTA and lysine chelates). This time, peroxidation (PI) and unsaturation coefficients (UI) as biomarker were analysed. These indices were calculated based on the FA profile in the foot and hepatopancreas of snails. The correlation of frequently used oxidation status indicators of organisms (catalase - CAT, glutathione peroxidase - GPx, selenium-dependent peroxidase - se-GPx, superoxide dismutase - SOD, glutathione transferase - GST, glutathione reductase - GR, glutathione - GSH, carbonyl protein - CP, thiobarbituric acid reactive substances - TBARS) with the rarely used UI and PI ratios was analysed. It was found that the 12-week micro-exposure to Zn and Cu did not inhibit but rather stimulated antioxidative defence at a sufficient level to increase the values of peroxidation/unsaturation indices in comparison to the control groups. Induction of an opposite process to oxidation of fatty acids was demonstrated. Maximum activities and amounts of antioxidants as well as minima of protein and lipid decomposition were recorded in groups supplemented with 0.75 mg/l Zn and 1.0 mg/l Cu. The possibility of a direct use of fatty acids as well as peroxidation/unsaturation indices as sensitive and reproducible biomarkers of exposure and oxidative physiological status in snails was confirmed. [ABSTRACT FROM AUTHOR]

The Holocene postglacial expansions offer a possibility to assess how quickly snails, with proverbially slow active dispersal and unclear passive dispersal capabilities, can naturally spread. We explore the possibilities and limitations of such an approach on an iconic European snail. We locate probable sources of postglacial expansion of Helix pomatia and date its earliest postglacial subfossil occurrences in Central Europe, close to presumed natural northern distribution limits. With dense sampling of the species native range, we found most of its mitochondrial diversity at c. 45 °N or more southerly. A hotspot in Bosnia and Serbia contributed to colonization of the Pannonian Basin, Carpathians and Bohemian Massif; however, the most widely distributed lineage has a more westerly centre of diversity, with a possible refugium in Italy. We revised the oldest occurrences post-dating the Late Pleniglacial from Czechia and Slovakia suggested by literature and radiocarbon-dated the preserved shell fragments. No reliably identified fragment yielded a date earlier than 10 121-9695 cal BP. Stratigraphy-based records presumed older turned out to be unreliable, making the argument for a direct dating approach. However, our results confirm that in the absence of northern refugia, H. pomatia must have been able to colonize the newly emerging postglacial habitats rapidly. [ABSTRACT FROM AUTHOR]

Metal regulation is essential for terrestrial gastropods to survive. In helicid snails, two metal-selective metallothionein (MT) isoforms with different functions are expressed. A cadmium-selective isoform (CdMT) plays a major role in Cd 2 + detoxification and stress response, whereas a copper-selective MT (CuMT) is involved in Cu homeostasis and hemocyanin synthesis. A third, non-metal-selective isoform, called Cd/CuMT, was first characterized in Cantareus aspersus . The aim of this study was to quantify the transcriptional activity of all three MT genes in unexposed and metal-exposed (Cd, Cu) embryonic Roman snails. In addition, the complete Cd/CuMT mRNA of the Roman snail ( Helix pomatia ) was characterized, and its expression quantified in unexposed and Cd-treated adult individuals. In embryos of Helix pomatia , the Cd/CuMT gene was induced upon Cu exposure. Its transcription levels were many times higher than that of the other two MT genes, and also exceeded by far the Cd/CuMT mRNA concentrations of adult snails. In the hepatopancreas of adult Roman snails, no Cd/CuMT could be detected at the protein level, irrespective of whether the snails had been exposed to Cd or not. This contrasts with the situation in the near relative, Cantareus aspersus . It appeared that the 3′-UTR of the Cd/CuMT mRNA differed largely between Cantareus aspersus and Helix pomatia , being larger in the latter species, with a number of putative binding sites for proteins and miRNAs known to inhibit mRNA translation. We suggest this as a possible mechanism responsible for the lack of Cd/CuMT protein expression in adult Roman snails. [ABSTRACT FROM AUTHOR]

Streptococcus pneumoniae is a common human pathogen and a major causal agent of life-threatening infections that can either be respiratory or non-respiratory. It is well known that the Helix pomatia (edible snail) agglutinin (HPA) lectin shows specificity for terminal αGalNAc residues present, among other locations, in the Forssman pentasaccharide (αGalNAc1→3βGalNAc1→3αGal1→4βGal1→4βGlc). Based on experiments involving choline-independent mutants and different growth conditions, we propose here that HPA recognizes the aGalNAc terminal residues of the cell wall teichoic and lipoteichoic acids of S. pneumoniae. In addition, experimental evidence showing that pneumococci can be specifically labeled with HPA when growing as planktonic cultures as well as in mixed biofilms of S. pneumoniae and Haemophilus influenzae has been obtained. It should be underlined that pneumococci were HPA-labeled despite of the presence of a capsule. Although some non-pneumococcal species also bind the agglutinin, HPA-binding combined with fluorescence microscopy constitutes a suitable tool for identifying S. pneumoniae and, if used in conjunction with Gram staining and/or other suitable technique like antigen detection, it may potentially facilitate a fast and accurate diagnosis of pneumococcal infections. [ABSTRACT FROM AUTHOR]

The first data regarding protein and mineral concentration during hibernation were obtained in the species Helix pomatia. Total proteins, albumins, globulins, Ca2+ and K+ concentrations were measured at the beginning of hibernation, end of hibernation and post-hibernation period (control group). Hemolymph was collected from the pericardial cavity. Total proteins were analyzed using the Biuret method, albumins were analyzed by BCG method, while calcium and potassium concentrations were obtained by CPC method and turbidimetric method, respectively. During hibernation the total protein, globulin and calcium levels were decreased, while the concentration of potassium was evidently increased. Total protein, globulin and calcium levels had the highest values in post-hibernation period. Exceptionally high values were obtained for calcium and globulin concentrations. Significant positive correlation between protein and globulin levels was established. Protein synthesis is the energy-utilizing process during metabolic depression and in our study decreasement of protein concentration in general has been shown during hibernation period. [ABSTRACT FROM AUTHOR]

Apart from their well-known culinary use, gastropod species such as Helix , which have a hydrogel-like mucus, are increasingly being exploited for cosmetic, bioengineering and medical applications. However, not only are the origin and composition of these “sticky” secretions far from being fully characterized, the number and morphology of the mucus glands involved is also uncertain. This study aims to characterize in detail the cutaneous glands of the Helix pomatia foot on morphological, histochemical and immunohistochemical levels. Hereby the focus is on the gland position and appearance on the foot sole as well as on the chemical nature of the different gland secretions. At least five different gland types can be distinguished by their microanatomy; three are located on the dorsal side and two on the ventral side of the foot sole. Most glands are reactive for acidic proteins and sugars such as mannose and fucose, indicating the presence of acidic glycosaminoglycans. One dorsal gland type shows high reactivity for acidic proteins only. The isolated mucus includes a certain amount of the elements chlorine, potassium and calcium ; evidence for lipids was also confirmed in the isolated mucus. The present results for Helix pomatia show a clear difference in the number of glands compared to the related species Helix aspersa (only four mucus glands); histochemically, the glands of both species similarly produce acidic proteins as well as acidic glycosaminoglycans. While calcium ions are known to play a role in mucus formation, the presence and function of other ions such as potassium still need to be clarified. [ABSTRACT FROM AUTHOR]

We analyzed the changes in the profile of fatty acids (FA) in the foot tissues and hepatopancreas (HP) of snails Helix pomatia exposed to five microdoses of zinc (0.1, 0.25, 0.5, 0.75, or 1 mg/l) administered in the form of a pure salt solution and in the form of EDTA and lysine chelates. Selection from a pool of 56 fatty acids analyzed in snail tissues yielded a set of 12 biomarker acids undergoing significant changes in contact with toxic substances. The selection criteria included the greatest percentage among the FA profile and their significant role in physiological processes. The proposed palette of acids of the biomarker FAs comprised C16:0; C18:0; C23:0; C18:1 n-9; C20:1 n-9; C18:2 n-6; C18:3 n-3; C20:2; C20:4 n-6; C20:5 n-3; C22:4 n-6; and C22:5 n-3, and saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs), determined separately in the foot tissues and hepatopancreas. The significant (p=0.01) influence of the dose as well as the source of the zinc on its' concentration in the tissues and on changes in the fatty acid profiles. Among the three zinc forms administered to the snails, the highest bioaccumulation of zinc in both tissues was noted in the group receiving the Zn-EDTA chelate. The content of PUFAs increased as the supplementation with zinc increased up to 0.75 mg/l, but at 1 mg/l, the share of these FAs began to decrease. This trend was observed in both analyzed tissue types - foot and hepatopancreas. The dose of 1 mg Zn/l might be considered as a threshold dose above which the saturation of FAs increases. The results proved that determination of FA profile in snails can be used in ecotoxicological research as a reliable test of the effect of trace doses of stressors. The micro-supplementation of the mollusks diet with zinc is an example of a non-routine approach to issues connected with both diet and toxicology. [ABSTRACT FROM AUTHOR]

On the basis of the analysis of genetic variation detectable by ISSR-PCR, the state of the gene pools of 14 populations of Roman snail Helix pomatia L. in the conditions of urbanized landscapes of the southeastern and eastern parts of the current range was examined. According to the data obtained, the majority of the studied populations of this mollusk are in satisfactory condition. This is evidenced by the increased level of genetic diversity ( H = 0.199 ± 0.025, I = 0.306 ± 0.035) and the high values of effective population size, calculated, on the basis of the straight-line regression equation, between the pairwise genetic and geographic distances (Ne = 2.0-4.9) that are comparable with indigenous common species of terrestrial mollusks. Despite the high level of differentiation (G = 0.255, Φ = 0.233, N = 0.822), the population distribution was not random ( R =-0.591, p = 0.0004) and corresponded to the model of isolation by distance. It is hypothesized that, in the adventitious colonies of this mollusk, effective formation of a balanced genetic structure takes place that, in the context of biological and ecological features, facilitates its adaptation to the conditions of an urban environment and the population of the new territories of Eastern Europe. [ABSTRACT FROM AUTHOR]

Two stages of selection from a pool of 56 fatty acids analyzed in Helix pomatia yielded a set of 12 biomarker acids undergoing significant changes in contact with three microdoses of toxic substances, i.e. three molluscicides containing metaldehyde, methiocarb, and potassium chloride (PC). The proposed palette of acids, including saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA), determined separately in the foot tissues and hepatopancreas of Gastropoda , can be used in ecotoxicological research as a reliable test of the effect of trace doses of stressors. The final set of the biomarker FA comprised C16:0; C18:0; C23:0; C18:1 n-9; C20:1 n-9; C18:2 n-6; C18:3 n-3; C20:2; C20:4 n-6; C20:5 n-3; C22:4 n-6; and C22:5 n-3. A clear physiological response manifested as changes in the content of fatty acids (FA) was observed in the snails even in the case of the lowest doses of the pollutants. All experimental factors analyzed, i.e., the dose (5, 10, or 15 μl 0.01% w/v concentration) and the type of preparation (metaldehyde, methiocarb or PC), had a significant (p ≤ 0.01) impact on the FA composition of the foot and hepatopancreas. Limitation of the analysis to a narrow pool of reactive FA meets the requirements of parameters of biomarkers of exposure and facilitates and accelerates visualization of the bioindicator organism's response to the presence of the stressor in the environment. [ABSTRACT FROM AUTHOR]

Olfaction, a chemosensory modality, plays a pivotal role in the orientation and behavior of invertebrates. The central olfactory processing unit in terrestrial stylomatophoran snails is the procerebrum, which contains NO synthesizing interneurons, whose oscillatory currents are believed to be the base of odor evoked memory formation. Nevertheless, in this model the up- and downstream events of molecular cascades that trigger and follow NO release, respectively, have not been studied. Immunocytochemistry and flow cytometry studies performed on procerebral neural perikarya isolated from the snail Helix pomatia revealed cell populations with discrete DAF-2 fluorescence, indicating the release of different amounts of NO. Glutamate increased the intensity of DAF-2 fluorescence, and the number of DAF-2 positive non-bursting interneurons, through a mechanism likely to involve an NMDA-like receptor. Similarly to glutamate, NO activation induced an increase in intracellular cGMP levels through activation of soluble guanylyl cyclase. Immunohistochemical localization of proteins possessing the phosphorylated target sequence of AGC family kinases (RXXS/T-P), among them protein kinase A (RRXS/T-P), showed striking similarities to the distribution of NOS/cGMP. Activators of cyclic nucleotide synthesis increased the AGC-kinase-dependent phosphorylation of discrete proteins with 28, 45, and 55 kDa mw. Importantly, exposure of snails to an attractive odorant induced hyperphosphorylation of the 28 kDa protein, and increased levels of cGMP synthesis. Protein S-nitrosylation and intercellular activation of protein kinase G were also suggested as alternative components of NO signaling in the snail procerebrum. The present results from Helix pomatia indicate an important role for procerebrum NO/cGMP/PKA signaling pathways in the regulation of olfactory (food-finding) behavior. [ABSTRACT FROM AUTHOR]

Water channel proteins, classified as a family of Membrane Intrinsic Proteins (MIPs) superfamily, enable rapid movement of water and small uncharged molecules through biological membranes. Although water channel proteins are required in several important processes characteristic for the animals, such as osmoregulation, mucus secretion, or defense against desiccation, molluscs, until now, have been very poorly explored in this aspect. Therefore, we decided to study MIPs in Helix pomatia L. applied as a model in studies on terrestrial snail physiology. Our studies consisted in: the snail organ transcriptome sequencing and consecutive bioinformatic analysis of the predicted protein, estimation of the encoding transcript expression (qPCR), investigation of the predicted protein function in the yeast Saccharomyces cerevisiae cells, and the phylogenetic analysis. We identified six water channel proteins, named HpAQP1 to HpAQP6. All of them were proven to transport water, two of them (HpAQP3 and HpAQP4) were also shown to be able to transport glycerol, and other two (HpAQP5 and HpAQP6) to transport H 2 O 2 . Phylogenetic analysis indicated that the proteins either fell into aquaporins (HpAQP1, HpAQP2 and HpAQP5) or formed new groups of invertebrate water channel proteins, not described until now, that we suggest to term malacoglyceroporins (HpAQP3 and HpAQP4) and malacoaquaporins (HpAQP6). Thus, the classification of animal water channels based on the vertebrate proteins and including aquaporin, aquaglyceroporin, S-aquaporin and AQP8-type grades does not reflect diversity of these proteins in invertebrates. The obtained results provide important data concerning diversity of water channel protein repertoire in aquatic and terrestrial invertebrates and should also contribute to the improvement of animal water channel classification system. [ABSTRACT FROM AUTHOR]