Background . The expansion of the territory of human habitation leads to inevitable interference in the natural range of distribution of one or another species of animals, some of which may be ...dangerous for human life. Scorpions—the Arachnida class and order Scorpiones—can be considered as such typical representatives. Scorpions of the Buthidae family pose a particular danger to humans. However, LD 50 has not yet been defined for many species of this family, in particular, new representatives of the genus Leiurus . Leiurus macroctenus is a newly described species of scorpion distributed in Oman, and the toxicity of its venom is still unknown. Estimating the LD 50 of the venom is the first and most important step in creating the antivenom and understanding the medical significance of the researched animal species. The purpose of this study was to determine the lethal dose (LD 100 ), the maximum tolerated dose (LD 0 ), and the average lethal dose (LD 50 ) in rats when using Leiurus macroctenus scorpion venom. Methods and Results . 15 sexually mature scorpions were used in the study, which were kept in the same conditions and milked by a common method (electric milking). For the study, 60 male rats were used, which were injected intramuscularly with 0.5 ml of venom solution with a gradual increase in the dose (5 groups, 10 rats in each), and 10 rats were injected intramuscularly with physiological solution as control group. LD calculations were done using probit analysis method in the modification of the method by V.B. Prozorovsky. The LD 0 of Leiurus macroctenus scorpion venom under the conditions of intramuscular injection was 0.02 mg/kg, LD 100 was 0.13 mg/kg, and LD 50 was 0.08 ± 0.01 mg/kg. Conclusions . The analysis of scientific publications and other sources of information gives reason to believe that Leiurus macroctenus has one of the highest values of LD 50 not only among scorpions but also among all arthropods in the world. All these point to the significant clinical importance of this species of scorpion and require further research that will concern the toxic effect of its venom on various organ systems. Determining the LD50 of the venom for new scorpion species is crucial for creating effective antivenoms and understanding the medical implications of envenomation by this species.
Despite clearly recognized links between increased body mass and increased risk for various pathological conditions, therapeutic options to treat obesity are still very limited. The aim of the ...present study is to explore the effect of low-molecular-mass collagen fragments obtained from the scales of Antarctic wild marine fish on rats' visceral and subcutaneous white adipose tissue in a high-calorie diet-induced obesity model.
The study was conducted on outbred rats, which were divided into 3 experimental groups: (
) control, consuming standard food (3.81 kcal/g), (
) obese group, consuming a high-calorie diet (5.35 kcal/g), and (
) obese group, consuming a high-calorie diet (5.35 kcal/g) with intragastric administration of low-molecular-mass collagen fragments (at a dose 1 g/kg of body mass during 6 weeks). Low-molecular-mass collagen fragments were obtained by a procedure that included collagen extraction from fish scales and enzymatic hydrolysis with pepsin. Apart from hematoxylin and eosin staining, fibrosis level was assessed by histochemical Van Gieson's trichrome picrofuchsin staining, and mast cells were analysed by toluidine blue O staining.
Group treated with low-molecular-mass fragments of collagen exhibited decreased rate of mass gain, relative mass, area occupied by collagen fibre of both visceral and subcutaneous adipose tissue, and cross-sectional area of both visceral and subcutaneous adipocytes. Treatment with low-molecular-mass fragments of collagen reduced the infiltration of immune cells, number of mast cells and their redistribution back to the septa. This was also accompanied by a decreased number of the crown-like structures formed by the immune cells, which are markers of chronic inflammation that accompanies obesity.
This is the first study that reports the anti-obesity effect of low-molecular-mass fragments produced as a result of controlled hydrolysis of collagen from the scales of Antarctic wild marine fish in the
model. Another novelty of this work is the observation that the tested collagen fragments not only reduce the body mass, but also improve the morphological and inflammatory parameters (decrease in the number of crown-like structures, immune cell infiltration, fibrosis and mast cells). Altogether, our work suggests that low-molecular-mass collagen fragments are a promising candidate for amelioration of some comorbidities linked to obesity.
Background. Scorpion stings may be life-threatening since their venoms are comprised of a wide range of toxins and other bioactive molecules, such as enzymes. At the same time, scorpion envenomation ...may increase matrix metalloproteases (MMPs) levels, which enhance proteolytic tissue destruction by venom. However, investigations on the impact of many scorpions’ venoms, such as those of Leiurus macroctenus, on tissue proteolytic activity and MMP levels have not yet been conducted. Methods and Results. The present study aimed to examine the total proteolysis levels in various organs after Leiurus macroctenus envenomation and evaluate the metalloproteases and serine proteases’ contributions to the total proteolytic activity. Changes in MMPs and TIMP-1 levels were tested as well. Envenomation led to a significant increase in proteolytic activity levels in all assessed organs, mostly in the heart (by 3.34 times) and lungs (by 2.25 times). Conclusions. Since EDTA presence showed a noticeable decrease in total proteolytic activity level, metalloproteases appeared to play a prominent role in total proteolytic activity. At the same time, MMPs and TIMP-1 levels were increased in all assessed organs, suggesting that Leiurus macroctenus envenomation causes systemic envenomation, which may induce multiple organ abnormalities, mostly because of the uncontrolled metalloprotease activity.
Nowadays, more than two billion inhabitants of underdeveloped tropical and subtropical countries are at risk of being stung by scorpions. Scorpion stings annually cause 2000–3000 deaths as they can ...lead to the respiratory and/or cardiovascular complications. Pathogenesis of lung damage under scorpion envenomation is often comprehensive. Respiratory failure can have a cardiogenic origin, associated with venom neurotoxin action. However, some venom components can stimulate pro-inflammatory signaling cascades followed by cytokines synthesis, recruit and activate immune cells, participating in the inflammatory response in lung injury. Scorpions of the Leiurus genus ("deathstalker") are one of the most dangerous Arthropoda. To date, 22 species of this genus have been described, but the venom composition and the mechanisms of tissues damage under envenomation have been studied to some extent only for L. quinquestriatus, L. hebraeus, and L. abdullahbayrami. Scorpions of L. macroctenus species are expected to be very hazardous, but the possibility of their venom cause inflammation in the lung tissue has not been investigated to date. Therefore, in this study, we focused on evaluating the levels of cytokines and their regulators – transcription factors (HIF-1α and NF-κB) and growth factors (FGF-2, VEGF, and EGF) – in rat lung homogenates after L. macroctenus envenomation. The results revealed a decrease in the levels of most pro-inflammatory cytokines (IL-6, IL-8, IL-1β and TNF-α) with simultaneous rise in the content of both anti-inflammatory cytokines (IL-4 and IL-10) and interferon-γ. Furthermore, the levels of all researched transcription factors and growth factors were shown to be increased too. The detected changes peak occurred at 24 h, whereas a tendency towards all indicators values normalization was observed in 72 h after venom injection. Thus, our results did not reveal signs of a classic inflammatory process in the lungs of rats injected with L. macroctenus venom. However, the obtained data indicate venom influence both on cytokine profile and on their regulators content in the rat lungs, which is a feature of certain alterations in the innate immune response, caused by studied venom components. But, the mechanisms of the changes we found require additional researches.
•L. macroctenus envenomation cause decrease in the levels of most pro-inflammatory cytokines.•Levels of transcription factors and growth factors increase after L. macroctenus envenomation.•L. macroctenus venom rise the content of anti-inflammatory cytokines and interferon-γ.•Peak of changes occurred at 24 h after L. macroctenus venom injection.•Components of the venom of the scorpion L. macroctenus activate the innate immune response.
Background: A growing number of reports indicate that amphibian skin secretions may have a remarkable medical importance; however, the effects of the components of some dermal secretions on blood ...platelets and hemostasis are inadequately recognized. Since our previous studies demonstrated that the general Bufo bufo skin secretions induced platelet aggregation in platelet-rich plasma, this work was designed to study the effects of the components of some fractions on platelet functions to comprehend its possible mechanism of action as platelet modulators. Methods: Chromatographic separation of B. bufo general skin secretions was carried out using size exclusion chromatography. Rabbit platelets were purified by column chromatography on Sepharose 4B. Various aspects of platelet function such as activation, aggregation, and adhesion were evaluated. Results: One fraction, out of 7, dose-dependently induced aggregation of isolated platelets and was used in further experiments. The studied fraction was shown to induce platelet adhesion onto fibrinogen-coated surface. Furthermore, the results demonstrated the effects of the fraction on some processes that involved in platelets activation: The fraction components facilitated (Ca2+) i mobilization and attenuated platelets Akt phosphorylation, but had no effect on platelet serotonin secretion. Membrane integrity was determined using lactate dehydrogenase (LDH) assay. No increased LDH release was recorded that means no platelet damage, which could lead to misinterpretation of the data, occurred. Conclusion: The results suggest that components of the B. bufo skin secretions may be a promising source of natural compounds which can modulate platelet functions.
Post-COVID-19 conditions are the subject of extensive scientific study. It is known that system disorders may persist in people who recover from COVID-19 for 3 to 12 months (in most cases). The first ...line of systemic disorders is dysfunction of the immune system, especially the cytokine profile. The mechanism of the launch of immune complications is currently unknown. We hypothesized that anti-SARS-CoV-2 IgG might trigger the development of post-COVID-19 complications. Our research aimed to study the cytokine profile (including IL-1β, IL-4, IL-6, IL-8, IL-10, IL-12β, TNF-α, IFN-γ) and the transcription factor NF-kB in the blood plasma of donor groups depending on various titers of anti-SARS-CoV-2 IgG. We determined the qualitative values of the cytokine parameters using ELISA (Enzyme Linked Immunosorbent Assay). We estimated the changes in the cytokine profiles in all donor groups. Differences between donor groups were established for each research parameter. We detected changes in NF-κB levels as a key transcription factor for the expression of inflammatory cytokines. The highest level was found in the donor group with a titer of anti-SARS-CoV-2 IgG 75 ± 5 Index (S/C). We detected some differences between donor groups in the levels of pro-inflammatory cytokines compared to a reference point. IL-1β, IL-6, IL-8, INF-γ, and TNF-α levels changed in most donor groups with titers of anti-SARS-CoV-2 IgG ≥ 10 ± 3 Index (S/C). In addition, we showed that the decrease in anti-inflammatory cytokine IL-4 in donor groups ranged from the titer of anti-SARS-CoV-2 IgG 55 ± 5 Index (S/C) to 85 ± 5 Index (S/C), but these changes for the anti-inflammatory cytokine IL-10 were not detected. We found that the cytokine profile may be affected during post-COVID-19 conditions. The cytokine profiles of the donor groups changed depending on the titers of anti-SARS-CoV-2 IgG. The obtained results testify to the fact that the antibody subpopulation may be a key reason for immune dysfunction, influencing the development of other pathological processes.
Problem of scorpion envenomation becomes more alarming each year. Main effects of scorpion venom are commonly believed to be related to its neurotoxic properties, yet severe symptoms may also be ...developed due to the uncontrolled enzymatic activity and formation of various bioactive molecules, including middle-mass molecules (MMMs). MMMs are considered as endogenous intoxication markers, their presence may indicate multiple organ failure. Scorpions, belong to the Leiurus macroctenus species, are very dangerous, nevertheless, effects of their venom on protein and peptide composition within the tissues remains unclear. In this work we have focused the attention on changes in protein and MMM levels and peptide composition in various organs during Leiurus macroctenus envenomation. The results revealed a decrease in protein level during envenomation as well as a significant increment of MMM210 and MMM254 levels in all assessed organs. Quantitative and qualitative compositions of various protein and peptide factions were continually changing. All of this may suggest that Leiurus macroctenus sting causes considerable destruction of cell microenvironment across all essential organs, providing systemic envenomation. In addition, MMM level increment may indicate endogenous intoxication development. Peptides, formed during envenomation, may possess various bioactive properties, analysis of which constitutes an area of further studies.
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•Leiurus macroctenus venom promotes alterations in protein quantitative and qualitative composition in most vital organs.•Decrement of protein levels mostly found in brain (by 16.4 %) and liver (by 14.7 %).•The most significant changes are observed in 24 h after Leiurus macroctenus venom injection.
The disease COVID-19, caused by SARS-CoV-2 infection, has a systemic effect and is associated with a number of pathophysiological mechanisms that mobilize a wide range of biomolecules. Cytokines and ...growth factors (GFs) are critical regulators of tissue damage or repair in osteoarthritis (OA) and are being recognized as key players in the pathogenesis of COVID-19. A clear understanding of the long-term consequences of SARS-CoV-2 infection, especially in patients with concomitant chronic diseases, is limited and needs to be elucidated. The study aimed to evaluate the degree of inflammation and levels of pro-angiogenic and hypoxic factors, as well as heat shock proteins HSP60 and HSP70 in plasma, of patients with OA after recovery from COVID-19.
The research involved patients of an orthopedic specialty clinic aged 39 to 80 diagnosed with knee OA. All examined patients were divided into three groups: the Control group included conditionally healthy donors, group OA included patients with knee OA mainly stage II or III and the group of OA and COVID-19 included patients with OA who had COVID-19. The plasma levels of pro-inflammatory molecules IL-1β, IL-6, TNF-α, NF-κB, angiogenic factors VEGF, FGF-2, PDGF, hypoxic factor HIF-1α and molecular chaperones HSP60 and HSP70 were measured by enzyme-linked immunosorbent assay.
The study showed that in both groups of patients, with OA and convalescent COVID-19, there was an increase in the plasma level of IL-1β and a decrease in TNF-α and NF-κB levels when compared to healthy controls. Systemic deregulation of the cytokine profile was accompanied by reduction in plasma levels of pro-angiogenic growth factors, most pronounced in cases of VEGF and PDGF. This analysis did not reveal any significant difference in the plasma level of HIF-1α. A decrease in the level of stress protein HSP60 in the blood of patients with OA, as well as those patients who have had SARS-CoV-2 infection, has been established.
The results suggest the potential role pro-inflammatory cytokines and angiogenesis-related growth factors in pathogenesis of both joint pathologies and long-term systemic post-COVID-19 disorders.
Background
Bladder cancer (BC) is an aggressive disease with a poor prognosis. A bladder tumor, like other malignant neoplasms, is characterized by the presence of both cancer cells and stromal cells ...which secrete cytokines, chemokines, growth factors, and proteolytic enzymes. One such class of proteolytic enzymes are serine proteases, which take part in the tumor microenvironment formation via supporting and contributing to tumor progression. This study aims to evaluate the proteolytic activity and serine protease contribution in plasma from BC patients.
Methods
The research involved patients of Alexandrovsky city clinical hospital aged 52–76 with transitional cell carcinoma of the bladder. All examined patients were divided into five groups: the control group included conditionally healthy donors, while other patients were grouped according to their tumor stage (I, II, III and IV). Plasma plasminogen levels were determined by enzyme-linked immunosorbent assay, and the potential activity was measured by chromogenic plasminogen assay. Serine proteases fractions were obtained by the affinity chromatography method, and enzyme concentration in the selected fractions were determined by the Bradford method. Serine proteases distribution was investigated by electrophoresis in a polyacrylamide gel.
Results
It was determined that the concentration, potential activity of plasminogen, and the total amount of serine proteases in plasma from BC patients were greater than the values of the corresponding indicators in healthy donors. This could be one of the factors contributing to increased proteolysis seen in the process of carcinogenesis. Plasminogen concentration in BC patients with stage IV disease; however, displayed a tendency to be reduced compared to earlier stages, and the potential activity of plasminogen was significantly lower in patients with stages III – IV BC. Futhermore, a tumor stage specific gradual decline in the serine protease plasma content was shown. The results of electrophoretic analysis established a significant diminishment in the percentage of high molecular weight components (under non-reducing conditions) and their complete disappearance (under reducing conditions) in plasma serine protease fractions from BC patients. A decline in the percentage of heavy and light plasmin chains in BC patients was also observed. Additionally, a rise in the degraded forms of plasminogen/plasmin content was seen in BC samples, as well as the presence of fractions corresponding to trypsin and NE (under non-reducing conditions) that were absent in the control samples.
Conclusion
The results indicate significant changes in the proteolytic activity of plasma, from BC patients when compared to healthy controls, which is accompanied by alterations in serine protease distribution caused by tumor microenvironment pecularlities at the different stages of oncopathology.
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