Search Results (259)

Background: Enzymes secreted by the digestive glands are excreted from the body with urine, sweat and feces, and they are also removed from the blood due to their participation in the enzymatic provision of the secretion entering the gastrointestinal tract. Objective: The aim of this work was to analyze the activity of pepsinogen, amylase and lipase in the coprofiltrate of pregnant women in each trimester of pregnancy and in the postpartum period, taking into account the timing and type of delivery (term, premature, late delivery or cesarean section). Methods: Data from studies of non-pregnant (n = 45) and pregnant (n = 193) women were analyzed. The materials for preparation coprofiltrate were collected during delivery. Pepsinogen activity was determined by proteolytic activity at pH = 1.5–2.0 using the tyrosine spectrophotometric method, while amylase activity was determined by the amyloclastic method of Karavey, and lipolytic activity was determined by a unified kinetic method using olive oil as a substrate. Outcomes: A small amount of pepsinogen was excreted in the coprofiltrate, and while the level of its excretion increased after childbirth, it remained below the control values. At the same time, an increase in the amylolytic activity of the coprofiltrate was observed in all groups of pregnant women examined from the first to the third trimester of pregnancy. In pregnant women, multidirectional changes in lipase activity were observed depending on the timing and type of delivery. Conclusions: At the end of pregnancy, amylolytic activity increased in all women, and pepsinase activity decreased compared to the indicators of non-pregnant women. No reliable differences were found in the lipolytic activity of the coprofiltrate in pregnant women at the end of pregnancy and the indicators of non-pregnant women. Full article

Plastic manufacturing involves using compounds that could be considered endocrine disruptors. Consequently, concern about the effect of these particles on the hormonal regulation of various systems, including the hypothalamic–pituitary–thyroid axis, has been increasing. By applying the Amphibian Metamorphosis Assay (AMA), the effects of irregular polystyrene microplastics (PS) MPs on the thyroid gland of Xenopus laevis were investigated. The histological effects on other organs of tadpoles were also studied. Tadpoles were exposed to 500 and 50 µg of virgin PS MP particles, (200 µm range)/L, administered by diet for 21 days. PS dietary exposure revealed statistically significant effects for the snout to vent length and the whole body length apical endpoints on day 21. The histological survey of both treatment groups revealed no noteworthy effects on the thyroid gland, digestive tract, or kidneys, but slight modifications to the liver. Mild ultrastructural modifications were detected in tadpoles’ enterocytes and hepatocytes in both treatment groups, but were likely to be reversible. Overall, our results contrast with previous research results in which effects were observed, but using different types, concentrations, and numbers of MPs. All this suggests the need for standardized methods for the environmental risk assessment of MPs/NPs (nanoplastics). Concern about the risk of NPs seems to be greater, and more studies with NP particles should be conducted. Full article

Vibrios are widespread in marine environments, and their persistence is often linked to natural reservoirs such as filter-feeding bivalves. This study investigated the capacity of the Mediterranean mussel, Mytilus galloprovincialis, to act as a reservoir of Vibrio harveyi using a GFP-tagged strain in controlled experiments. Mussels (shell length 4–6 cm) were exposed to V. harveyi gfp in estuarine and seawater at 12 °C and 20 °C over six days. Bacterial accumulation in gills, digestive gland, and gonads, as well as in feces and pseudofeces, was quantified, and the immune response following microbial challenge was assessed by histopathological analysis. Mussels actively removed V. harveyi from the water, but not completely. Vibrios were rapidly accumulated in organs, with the highest densities in the digestive gland (up to 10⁷–10⁸ CFU g⁻¹), and substantial bacterial loads detected in biodeposits (1.55–3.77 × 10⁷ CFU g⁻¹). Salinity had a greater effect than temperature on bacterial accumulation, with consistently higher counts in seawater assays. Concurrently with bacterial accumulation, mussels activated their immune system, as evidenced by the detection of granulocytomas and hemocytic infiltrations. Overall, these results demonstrate that M. galloprovincialis accumulates V. harveyi in tissues and biodeposits, serving as a natural reservoir for this bacterium. Full article

This study investigated the ecotoxicological impacts of environmentally relevant concentrations (0.05, 0.50, and 5.00 mg/L) of nickel nanoparticles (Ni-NPs) by assessing oxidative stress biomarkers. The worm Hediste diversicolor, the bivalve Mytilus spp., and the fish Sparus aurata were chronically exposed to Ni-NPs for 28 days, and glutathione S-transferases (GST), catalase (CAT), and thiobarbituric acid reactive substances (TBARS) levels were measured to evaluate biochemical responses. GST activity increased in H. diversicolor and the liver of S. aurata, suggesting a key role for this enzyme in Ni-NPs detoxification. CAT activity was inhibited in the digestive gland of Mytilus spp. at the highest Ni-NPs concentration, indicating possible disruption of antioxidant defense. TBARS levels rose significantly in the gills of Mytilus spp. exposed to high Ni-NP concentrations, suggesting oxidative damage beyond detoxification capacity. In contrast, TBARS decreased in the digestive gland of Mytilus and in H. diversicolor, possibly due to compensatory upstream antioxidant responses. These findings indicate that each species exhibits distinct adaptive responses to Ni-NP exposure. Overall, this study highlights the need to consider species- and tissue-specific responses when performing ecotoxicological risk assessments of nanomaterials. Full article

Utilizing a multi-biomarker approach, we assessed the potential adverse effects of pollutants on subcellular responses in the digestive gland of the freshwater mussel Unio crassus from a historically contaminated lowland section (KIZ) of the river Mrežnica compared to its less impacted upstream karstic section (REF) and their seasonality (spring vs. autumn). This approach accounted for the diverse modes of action of pollutants by including biomarkers of metal exposure (metallothioneins, MT), general stress (total cytosolic proteins, TP), antioxidative capacity (catalase, CAT; glutathione, GSH; glutathione-S-transferase, GST), oxidative damage (malondialdehyde, MDA), and neurotoxicity (acetylcholinesterase, AChE). Only in spring, MT concentrations were 15% higher at the REF site (4.38 ± 1.06 µg mg proteins⁻¹) compared to the KIZ site (3.69 ± 0.63 µg mg proteins⁻¹), likely related to elevated Cd bioaccumulation due to the karstic substrate. Regardless of the season, mussels from KIZ showed consistently lower TP and GSH, with significantly higher CAT, GST, and MDA levels, indicating elevated stress, activation of antioxidant defenses, and oxidative damage from chronic exposure to pro-oxidant pollutants, including metal(loid)s and organic contaminants (e.g., ibuprofen, nicotine). Compared to the REF site, AChE activity at the KIZ site was higher in late spring and lower in early autumn, indicating seasonal variability in AChE activity at the contamination-impacted location driven by fluctuating exposure to neurotoxicants, such as drugs and insecticides. Overall, biomarker responses indicated that mild historical pollution, reinforced by current low-capacity sources, has an observable impact on mussel health, posing long-term risks to sediment-dwelling aquatic organisms. Full article

Fipronil (FIP) and imidacloprid (IMID) are two of the most commonly used ectoparasiticides to control parasites in pets. Compared with those of farm animals, their environmental risks have generally been considered low because of their limited use; however, the growing pet population and evolving treatment practices make this assumption challenging. To assess these risks, water samples were collected at an animal shelter in Italy to monitor the abundance of ectoparasiticides in aquatic environments. Additionally, laboratory-based ecotoxicological assays were carried out on a range of marine non-target species across different trophic levels (algae, copepods, and mussels). In vitro toxicity tests on human epithelial cell cultures were also implemented to examine potential cytotoxic effects at the levels of human exposure detectable in a domestic setting after pet treatment. Wastewater samples from the shelter contained 0.18 µg L⁻¹ of IMID, 0.50 µg L⁻¹ of FIP, and 0.20 µg L⁻¹ of FIP-sulfone, with these concentrations remaining stable for 60 days. Chronic exposure to FIP and IMID at 30.0 µg L⁻¹ impaired the mobility of the copepods. The EC₁₀ and EC₂₀ values were determined to be 1.7 (0.06–6.59) µg L⁻¹ and 2.8 (0.436–8.51) µg L⁻¹ for FIP and 2.6 (0.80–6.33) µg L⁻¹ and 7.6 (3.12–15.8) µg L⁻¹ for IMID, respectively. FIP and IMID exposure led to lipid peroxidation in the digestive glands and gills of mussels, whereas only IMID exposure increased acetylcholinesterase activity in the digestive glands at concentrations between 0.5 and 5.0 µg L⁻¹. Additionally, both fipronil and imidacloprid triggered the production of reactive oxygen species and lipid peroxidation and decreased the viability of human keratinocyte cells in a concentration-dependent manner. These findings highlight the persistence and potential risks of FIP and IMID, stressing the need for stricter regulations and further research on chronic environmental exposure to safeguard ecosystems and public health. Full article

Argentina is among the top consumers of herbicides, yet studies on their environmental and health impact remain scarce. This work aimed to evaluate the effects of herbicide exposure on Pomacea canaliculata as potential biomarkers of contamination. Specifically, we investigated whether paraquat (Pq) and fluroxypyr (Fx) alter enzymatic antioxidant defenses in tissues following acute exposure and induce histological modifications in the digestive gland (DG), particularly in symbiotic corpuscles, after chronic exposure. The nominal no-observed-effect concentration on lethality (NOEC_L) values were 3.62 µg/g dry mass (DM) for Pq and 10.42 µg/g DM for Fx. After acute exposure, superoxide dismutase activity decreased in the DG but increased in the kidney for both herbicides. Catalase activity decreased in the gills but increased in the kidneys of exposed snails, while glutathione-S-transferase activity increased in the DG and kidney after Pq exposure. Following chronic exposure (Pq: 1.45 µg/g DM; Fx: 6.94 µg/g DM), epithelial thickening and vacuolization were observed in Fx-exposed snails. Morphometric analysis of the DG showed that Pq reduced the epithelial occupancy of the symbiont’s vegetative form while increasing its cystic form. These findings indicate that both herbicides impact antioxidant defenses, DG function and host–symbiont interactions, reinforcing the suitability of P. canaliculata as bioindicator organisms. Full article

Snakebite envenoming constitutes a significant global health issue, particularly in Africa, where venomous species such as Echis vipers and Dendroaspis mambas pose substantial risks to human health. This study employs a standardized venomics workflow to comprehensively characterize and comparatively quantify the venom composition of nine medically relevant snake species chosen from among the deadliest in Africa. Utilizing shotgun venom proteomics and venom gland transcriptomics, we report detailed profiles of venom complexity, highlighting the relative abundance of dominant toxin families such as three-finger toxins and Kunitz-type proteins in Dendroaspis, and metalloproteinases and phospholipases A₂ in Echis. We delineate here the relative abundance and structural diversity of venom components. Key to our proteomic approach is the implementation of Multi-Enzymatic Limited Digestion (MELD), which improved protein sequence coverage and enabled the identification of rare toxin families such as hyaluronidases and renin-like proteases, by multiplying the overlap of generated peptides and enhancing the characterization of both toxin and non-toxin components within the venoms. The culmination of these efforts resulted in the construction of a detailed toxin database, providing insights into the biological roles and potential therapeutic targets of venom proteins and peptides. The findings here compellingly validate the MELD technique, reinforcing its reproducibility as a valuable characterization approach applied to venomics. This research significantly advances our understanding of venom complexity in African snake species, including representatives of both Viperidae and Elapidae families. By elucidating venom composition and toxin profiles, our study paves the way for the development of targeted therapies aimed at mitigating the morbidity and mortality associated with snakebite envenoming globally. Full article

The thyroid is a vital endocrine organ that regulates metabolism, heart rate, respiration, digestion, body temperature, brain development, skin and bone maintenance, and reproduction and fertility. Thyroid cancer (TC) is the most common endocrine malignancy, with an estimate of 44,020 new cases in 2025. Incidence has been increasing, most notably at 4–5% per year in young adults. Papillary thyroid cancer (PTC), the most common TC subtype, accounts for approximately 80% of newly diagnosed TC cases. Furthermore, 2290 deaths are expected from the disease in 2025, with survival at over 98% with treatment. However, as PTC occurs most frequently in young women, recurrences are frequent and the 10-year disease-specific survival rate for advanced PTC is less than 50%. This narrative review aims to describe the current understanding of the thyroid gland, the incidence and subtypes of thyroid cancer, and specifically the diagnosis, prognosis, treatment, and recurrence of PTC. This is supplemented by the role of molecular pathways and biomarkers in PTC. Full article

Nutraceuticals are gaining research interest due to their beneficial potential and their use to counter the impact of emerging contaminants on natural ecosystems. Particularly, during the COVID-19 pandemic, the use of personal hygiene/care products and disinfectants increased significantly. These products contain several substances in their formulations, including surfactants, which have proven to be hazardous to the entire aquatic ecosystem. In the present study, bergamot (Citrus bergamia) peel extract was used as a nutraceutical to counteract the toxicity of sodium lauryl sulphate (SLS), a common anionic detergent with antimicrobial activity. Specimens of Mytilus galloprovincialis, were exposed to SLS (0.01 mg/L), bergamot peels’ extract (BRG: 5 mg/L), and their mixture for 14 days. The cellular and physiological alterations in haemocytes, digestive gland (DG) and gill cells were analysed. The analyses included cell viability of haemocytes and DG cells (trypan blue exclusion assay and the neutral red retention test); the ability of DG cells to regulate their volume (RVD); haemocyte phagocytic activity; expression of genes involved in antioxidant response (Cu/ZnSOD, MnSOD, Hsp70, and CYP4Y) on gills and DG; the energy efficiency of the organism through byssus production; and the measurement of key macromolecules, including total lipid and fatty acid content, total protein, tocopherols and carotenoids, which play a key role in maintaining physiological and metabolic functions in the organism. Overall, significant differences emerged between the control (CTR) and treated groups, with the CTR and BRG groups resembling each other, while the SLS-treated groups showed significant alterations. Meanwhile, the groups exposed to the combination showed a recovery, suggesting the potential beneficial effect of the BRG. Full article

Pain is a significant global public health issue that can interfere with daily activities, sleep, and interpersonal relationships when it becomes chronic or worsens, ultimately impairing quality of life. Despite ongoing efforts, the efficacy of pain treatments in improving outcomes for patients remains limited. At present, the challenge lies in developing a personalized care and management plan that helps to maintain patient activity levels and effectively manages pain. Neuropathic pain is a chronic condition resulting from damage to the somatosensory nervous system, significantly impacting quality of life. It is partly thought to be caused by inflammation and oxidative stress, and clinical research has suggested a link between this condition and diet. However, these links are not yet well understood and require further investigation to evaluate the pathways involved in neuropathic pain. Specifically, the question remains whether supplementation with dietary antioxidants, such as melatonin, could serve as a potential adjunctive treatment for neuropathic pain modulation. Melatonin, primarily secreted by the pineal gland but also produced by other systems such as the digestive system, is known for its anti-inflammatory, antioxidant, and anti-aging properties. It is found in various fruits and vegetables, and its presence alongside other polyphenols in these foods may enhance melatonin intake and contribute to improved health. The aim of this review is to provide an overview of neuropathic pain and examine the potential role of melatonin as an adjunctive treatment in a neuro-nutritional approach to pain management. Full article

Fish are vital for material cycling and energy flow in aquatic ecosystems. The genus Triplophysa, with over 100 known species, is significant in the Central Asian highlands’ freshwater ecosystems. T. strauchii and T. tenuis, as representatives, occupy distinct ecological niches and face challenges from climate change and human activities. There is a lack of research on Triplophysa fishes’ digestive systems, especially comparative studies, so this research aims to fill this gap. In September 2024, 40 samples of T. strauchii were collected from Sayram Lake and 40 samples of T. tenuis were collected from the Muzat River in Xinjiang. After acclimation, morphological observations (measuring fish and digestive tract parameters) and histological analyses (paraffin sectioning, HE staining, and microscopy) were carried out. The data were sorted in Excel and analyzed with an independent samples t-test in SPSS 27.0. Morphologically, T. strauchii has an obtuse snout, terminal mouth, specific upper lip papillae, and an S-shaped intestine about (1.45 ± 0.11) times its body length, while T. tenuis has an arc-shaped subterminal mouth, fringed papillae, and a spiral-shaped intestine around (0.82 ± 0.09) times its body length. Both possess a digestive tract, glands, and a hepatopancreas attached to the mesentery. Histologically, a large number of club cells were found in the oropharyngeal cavities of both species; their secretions have an adhesive effect on food, aiding food selection. Their digestive systems vary in structure and cell composition: the oropharyngeal cavity has three layers; the esophagus has four layers with more goblet cells in T. strauchii; the stomach has three regions without goblet cells and a thicker muscular layer in T. strauchii; the intestinal wall has four layers with different villi and goblet cell distributions; the hepatopancreas has lobules; and T. strauchii has a typical portal area. In conclusion, this study systematically compared the gastrointestinal systems of T. strauchii and T. tenuis for the first time, revealing significant structural differences related to their niches and feeding patterns as adaptations to specific environments. It fills the research gap, provides a basis for exploring fish ecological adaptation and environmental impacts on digestion, offers new ideas for Triplophysa protection strategies, and guides fish evolutionary biology research and Triplophysa resource protection and utilization. Full article

Bivalve microbiota play a vital role in host health, supporting nutrient processing, immunity, and disease resistance. However, the increasing hypoxia in Chilean coastal waters, caused by climate change and eutrophication, threatens to disrupt this microbial balance, potentially promoting pathogens and impairing essential functions. Mytilus chilensis is vulnerable to hypoxia-reoxygenation cycles, yet the effects on its microbiota remain poorly understood. This study investigates the impact of hypoxia on the structure and functional potential of the microbial communities residing in the gills and digestive glands of M. chilensis. Employing full-length 16S rRNA gene sequencing, we explored hypoxia’s effects on microbial diversity and functional capacity. Our results revealed significant alterations in the microbial composition, with a shift towards facultative anaerobes thriving in low oxygen environments. Notably, there was a decrease in dominant bacterial taxa such as Rhodobacterales, while opportunistic pathogens such as Vibrio and Aeromonas exhibited increased abundance. Functional analysis indicated a decline in critical microbial functions associated with nutrient metabolism and immune support, potentially jeopardizing the health and survival of the host. This study sheds light on the intricate interactions between host-associated microbiota and environmental stressors, underlining the importance of managing the microbiota in the face of climate change and aquaculture practices. Full article

Bivalves serve as the first intermediate hosts in the life cycles of some digeneans, but little is known about their larval stages along the southwestern Atlantic coast. These larvae may provide valuable insights into the ecological role of mollusks in parasite life cycles and marine food webs. This study offers a morphological, histological, and molecular (ITS2, 28S rDNA) description of the larval stages of three digenean species parasitizing the bivalve Jukesena foveolata in the Beagle Channel, Tierra del Fuego Province, Argentina. Sporocysts containing cercariae of a monorchiid species were found infecting the gonads and digestive glands (p = 2%), while metacercariae were encysted in the foot (p = 7%). Additionally, metacercariae of Renicola sp. (Renicolidae) were located between the tubules of the digestive gland (p = 2%), and metacercariae of Bartolius sp. (Gymnophallidae) were found in the extrapallial space (between the mantle and the valve, p = 13.5%), where they elicited a histopathological reaction with the secretion of a calcareous, igloo-shaped coating. The monorchiid larvae are described here for the first time in this bivalve, with fish as their definitive hosts. Metacercariae of Renicola sp. and Bartolius sp., both of which use coastal birds as definitive hosts, have been previously recorded in other mollusks from the Argentine coast. This study contributes to our understanding of the life cycles of digeneans from the southwestern Atlantic coast and the role of bivalve hosts in marine food webs. Full article

Nuclear power plants utilize great quantities of seawater to cool down, resulting in substantial warm water discharges that may affect nearby fisheries and marine ecosystems. This study focused on Crassostrea (Magallana) ariakensis, a commercially farmed oyster species along the southern coast of China. To evaluate the thermal impacts of warm water discharges from nuclear power plants, indoor simulations replicated seasonal water temperature conditions near coastal facilities (26 °C in spring and autumn, 16 °C in winter, and 30 °C in summer). We conducted thermal tolerance static and dynamic experiments, along with a 51-day long-term experiment on suitable growth under different acclimation temperatures. The thermal effects of warm water discharges on C. ariakensis were systematically assessed through survival, growth, digestibility, and nutritional quality. The results showed that the discomfort temperature range of C. ariakensis was (48.6 ± 1.2)~(58.9 ± 3.0) °C, the critical thermal maxima (CTM) value range of C. ariakensis was (51.6 ± 1.4)~(61.2 ± 2.2) °C, and the incipient lethal temperature (ILT₅₀) of C. ariakensis was 45.61 °C, 53.71 °C, and 55.90 °C, respectively; all these values increased gradually with the rise of acclimation temperature. After the 51-day long-term experiment on suitable growth, the temperature increase of 1 °C, 2 °C and 4 °C did not affect the soft tissue wet weight, condition index, moisture content, and fat content of C. ariakensis, but the amylase activity in digestive gland tissue decreased in different temperature experimental groups. The experimental results show that the influence of temperature rise on the growth and physiological metabolism of C. ariakensis is limited. However, based on the normal habitat temperature in summer, the long-term effects of temperature rise caused by warm water discharges need to be paid attention to. Full article