Insulin and Metformin Administration: Unravelling the Multifaceted Association with Mortality across Various Clinical Settings Considering Type 2 Diabetes Mellitus and COVID-19.

Due to the molecular mechanisms of action of antidiabetic drugs, they are considered to be effective in the treatment of both COVID-19 and the post-COVID-19 syndromes. The aim of this study was to determine the effect of administering insulin and metformin on the mortality of patients with type 2 diabetes (T2DM) with symptomatic COVID-19 with the use of logistic regression models. The association between death and insulin and metformin was weak and could not be included in the multivariate model. However, the interaction of both drugs with other factors, including remdesivir and low-molecular-weight heparin (metformin), age and hsCRP (insulin), modulated the odds of death. These interactions hint at multifaceted (anti-/pro-) associations of both insulin and metformin with the odds of death, depending on the patient's characteristics. In the multivariate model, RDW-SD, adjusted with low-molecular-weight heparin treatment, age, sex and K+, was associated with mortality among patients with COVID-19 and T2DM. With a 15% increase in RDW-SD, the risk of death increased by 87.7%. This preliminary study provides the foundations for developing further, more personalized models to assess the risk of death in T2DM patients, as well as for identifying patients at an increased risk of death due to COVID-19.

Effect of advanced glycation end-products in a wide range of medical problems including COVID-19.

Glycation is a physiological process that determines the aging of the organism, while in states of metabolic disorders it is significantly intensified. High concentrations of compounds such as reducing sugars or reactive aldehydes derived from lipid oxidation, occurring for example in diabetes, atherosclerosis, dyslipidemia, obesity or metabolic syndrome, lead to increased glycation of proteins, lipids and nucleic acids. The level of advanced glycation end-products (AGEs) in the body depends on rapidity of their production and the rate of their removal by the urinary system. AGEs, accumulated in the extracellular matrix of the blood vessels and other organs, cause irreversible changes in the biochemical and biomechanical properties of tissues. As a consequence, micro- and macroangiopathies appear in the system, and may contribute to the organ failure, like kidneys and heart. Elevated levels of AGEs also increase the risk of Alzheimer's disease and various cancers. In this paper, we propose a new classification due to modified amino acid residues: arginyl-AGEs, monolysyl-AGEs and lysyl-arginyl-AGEs and dilysyl-AGEs. Furthermore, we describe in detail the effect of AGEs on the pathogenesis of metabolic and old age diseases, such as diabetic complications, atherosclerosis and neurodegenerative diseases. We summarize the currently available data on the diagnostic value of AGEs and present the AGEs as a therapeutic goal in a wide range of medical problems, including SARS-CoV-2 infection and so-called long COVID.

Alcoholic Liver Disease Is Associated with Elevated Plasma Levels of Novel Advanced Glycation End-Products: A Preliminary Study.

Elucidating the biochemical mechanisms associated with the progression of alcoholic liver disease (ALD) to more advanced stages such as alcoholic hepatitis (AH) remains an important clinical and scientific challenge. Several hypotheses point to the involvement of advanced glycation end-products (AGEs) in alcohol-associated liver injuries. Recently, we determined the structure of a synthetic, melibiose-derived AGE (MAGE), which was an analog of the novel AGE subgroup AGE10. The primary objective of our study was to determine whether AGE10 was associated with alcoholic hepatitis. The secondary objective was to provide a diagnostic accuracy of AGE10 in AH. To achieve this objective, we examined the plasma levels of AGE10 in 65 healthy individuals and 65 patients with AH. The AGE10 level was measured using a competitive ELISA. Our study confirmed that patients with AH had significantly higher plasma concentrations of AGE10 compared with healthy controls (184.5 ± 71.1 µg/mL and 123.5 ± 44.9 µg/mL, respectively; p < 0.001). In addition, AGE10 showed an acceptable performance as a diagnostic marker of AH, with an AUC of 0.78. In conclusion, AH was associated with elevated levels of novel advanced glycation end-product AGE10.

Association of Novel Advanced Glycation End-Product (AGE10) with Complications of Diabetes as Measured by Enzyme-Linked Immunosorbent Assay.

Advanced glycation end-products (AGEs) contribute to vascular complications and organ damage in diabetes. The unique AGE epitope (AGE10) has recently been identified in human serum using synthetic melibiose-derived AGE (MAGE). We aimed at developing ELISA for AGE10 quantification, determining whether AGE10 is present in diabetic patients (n = 82), and evaluating its association with diabetic complications. In a competitive ELISA developed, the reaction of synthetic MAGE with anti-MAGE was inhibited by physiological AGE10 present in serum. In this assay, new murine IgE anti-MAGE monoclonal antibodies, which do not recognize conventional AGEs, a synthetic MAGE used to coat the plate, and LMW-MAGE (low molecular mass MAGE) necessary to plot a standard curve were used. AGE10 was significantly higher in patients with microangiopathy, in whom it depended on treatment, being lower in patients treated with aspirin. AGE10 levels were positively correlated with estimated glomerular filtration rate (eGFR) and negatively with creatinine. As a marker of stage ≥3 chronic kidney disease or microangiopathy, AGE10 displayed moderate overall accuracy (respectively, 69% and 71%) and good sensitivity (82.6% and 83.3%) but poor specificity (58.1% and 57.8%). In conclusion, newly developed immunoassay allows for AGE10 quantification. AGE10 elevation is associated with microangiopathy while its decrease accompanies stage ≥3 chronic kidney disease.

Role of Advanced Glycation End-Products and Other Ligands for AGE Receptors in Thyroid Cancer Progression.

To date, thyroid cancers (TCs) remain a clinical challenge owing to their heterogeneous nature. The etiopathology of TCs is associated not only with genetic mutations or chromosomal rearrangements, but also non-genetic factors, such as oxidative-, nitrosative-, and carbonyl stress-related alterations in tumor environment. These factors, through leading to the activation of intracellular signaling pathways, induce tumor tissue proliferation. Interestingly, the incidence of TCs is often coexistent with various simultaneous mutations. Advanced glycation end-products (AGEs), their precursors and receptors (RAGEs), and other ligands for RAGEs are reported to have significant influence on carcinogenesis and TCs progression, inducing gene mutations, disturbances in histone methylation, and disorders in important carcinogenesis-related pathways, such as PI3K/AKT/NF-kB, p21/MEK/MPAK, or JAK/STAT, RAS/ERK/p53, which induce synthesis of interleukins, growth factors, and cytokines, thus influencing metastasis, angiogenesis, and cancer proliferation. Precursors of AGE (such as methylglyoxal (MG)) and selected ligands for RAGEs: AS1004, AS1008, and HMGB1 may, in the future, become potential targets for TCs treatment, as low MG concentration is associated with less aggressive anaplastic thyroid cancer, whereas the administration of anti-RAGE antibodies inhibits the progression of papillary thyroid cancer and anaplastic thyroid cancer. This review is aimed at collecting the information on the role of compounds, engaged in glycation process, in the pathogenesis of TCs. Moreover, the utility of these compounds in the diagnosis and treatment of TCs is thoroughly discussed. Understanding the mechanism of action of these compounds on TCs pathogenesis and progression may potentially be the grounds for the development of new treatment strategies, aiming at quality-of-life improvements.

Advanced glycation end products and their receptors in serum of patients with type 2 diabetes.

Glycation is a non-enzymatic process involving the reaction of reducing sugars or reactive oxoaldehyde with proteins, lipids or nucleic acids, which results in the formation of advanced glycation end products (AGEs). The presented work discusses the glycation process in people with advanced stage of type 1 or type 2 diabetes. The concentration of different AGEs and their receptors for 58 serum samples was determined by ELISA and by spectrofluorimetric methods. In addition to fluorescent low molecular weight and protein-bound AGEs, we have also marked a new class of AGEs: melibiose-derived glycation product (MAGE). Our attention was also focused on the two groups of AGEs receptors: scavenger receptors (SR-A and SR-B) and RAGE. The correlation between the SR-AI scavenging receptors concentration and the fluorescence of AGEs as well as diabetes biological markers: GFR, creatinine contentration and HbA1c was demonstrated. A relationship between the concentration of AGEs and their receptors was also found in serum sample of patients treated with the metformin and aspirin. Furthermore, the concentration of SR-AI scavenger and the fluorescence of total AGEs was significantly lower in treated patients than in non treated patients. AGEs have also been found to contribute to the development of cardiovascular disease, atherosclerosis and diabetic complications, what could be deduced from the correlation of AGEs level and HDL cholesterol or uric acid level. Thus, it was confirmed that AGEs are involved in the pathomechanism of diabetes and other degenerative diseases. Nowadays, it is believed that AGEs due to the long time remaining in the body may be an important diagnostic marker. Their determination may allow monitoring the progression of the disease and the effectiveness of the therapy.

The melibiose-derived glycation product mimics a unique epitope present in human and animal tissues.

Non-enzymatic modification of proteins by carbohydrates, known as glycation, leads to generation of advanced glycation end-products (AGEs). In our study we used in vitro generated AGEs to model glycation in vivo. We discovered in vivo analogs of unusual melibiose-adducts designated MAGEs (mel-derived AGEs) synthesized in vitro under anhydrous conditions with bovine serum albumin and myoglobin. Using nuclear magnetic resonance spectroscopy we have identified MAGEs as a set of isomers, with open-chain and cyclic structures, of the fructosamine moiety. We generated a mouse anti-MAGE monoclonal antibody and show for the first time that the native and previously undescribed analogous glycation product exists in living organisms and is naturally present in tissues of both invertebrates and vertebrates, including humans. We also report MAGE cross-reactive auto-antibodies in patients with diabetes. We anticipate our approach for modeling glycation in vivo will be a foundational methodology in cell biology. Further studies relevant to the discovery of MAGE may contribute to clarifying disease mechanisms and to the development of novel therapeutic options for diabetic complications, neuropathology, and cancer.

Advanced glycation end products derived from serum albumin modification by glucose (AGE-1) reflect clustering of lipid-associated metabolic abnormalities and are decreased in patients treated with acarbose: A cross-sectional study.

BACKGROUND: Advanced glycation end products (AGEs) are formed during protein modification by a reduction of sugars or reactive aldehydes. Depending on the pathology, various AGEs may be formed. They are stable compounds and are considered as potential diseases markers. OBJECTIVES: The objective of this study was to assess glucose-mediated albumin modification that yields non-standard epitopes of AGEs (AGE-1) in diabetes and in associated metabolic abnormalities. MATERIAL AND METHODS: The AGE-1, expressed as median AGE-1 level and AGE-1 positivity, was determined in 246 individuals (198 with prediabetes/diabetes) using a new slot-dot-blot method (allowing for detection of barely traceable analytes) and related to the presence of diabetes-associated metabolic abnormalities and complications, and treatment. RESULTS: The AGE-1 level was higher in patients with prediabetes/diabetes than in controls. Its elevation was associated with metabolic syndrome (MetS), obesity, hyperlipidemia, and non-alcoholic fatty liver disease (NAFLD) but not with diabetic control or microand macroangiopathy, except for atherosclerotic plaques formation in carotid arteries. The AGE-1-positive patients had higher triglycerides and lower high-density lipoprotein (HDL)-cholesterol. In patients untreated with aspirin, AGE-1 positivity was associated with higher C-reactive protein (CRP) level. Treatment with aspirin, sulfonylureas and gliptins was associated with higher AGE-1 level and with dyslipidemia medications with higher AGE-1 positivity. In patients with abnormal glucose metabolism, acarbose treatment was associated with lower AGE-1 positivity. Multivariate analysis showed MetS, carotid artery plaques, NAFLD, and treatment with aspirin and acarbose to be independently associated with AGE-1 positivity. CONCLUSIONS: Unlike standard AGEs, AGE-1 is more tightly associated with abnormalities in lipid than glucose metabolism, and lower in patients treated with acarbose but not with other antidiabetics.

Non-standard AGE4 epitopes that predict polyneuropathy independently of obesity can be detected by slot dot-blot immunoassay.

BACKGROUND: Advanced glycation end-products (AGEs) are formed during cascade reactions between reducing sugars or reactive aldehydes and proteins, lipids or DNA molecules. They constitute a group of various stable compounds. Advanced glycation end-products are considered potential biomarkers of metabolic disorders. However, so far only a few methods to determine the level of individual AGEs have been developed. OBJECTIVES: The aim of the study was to compare the efficiency of the slot-dot blot method and direct enzyme-linked immunosorbent assay (ELISA) in detecting non-standard epitopes of methylglyoxal (MGO)-modified proteins (AGE4) found in diabetes serum in trace amounts, and to assess AGE4 in diabetes and associated metabolic abnormalities. MATERIAL AND METHODS: The presence of AGE4 was detected using 2 methods: direct ELISA and the slot-dot blot method - a newly developed immunoassay based on monoclonal, commercially available antibody detection of non-standard AGE epitopes. AGE4 quantification, expressed as median AGE4 in arbitrary units (AU) and AGE4 positivity (the percent of samples with detectable AGE4) was related to diabetes-associated metabolic abnormalities, complications and treatment. RESULTS: Slot-dot blot was significantly more efficient than ELISA in detecting non-standard AGE4 epitopes. AGE4 positivity was less frequent in patients with microangiopathy and in those with polyneuropathy. In patients with abnormal glucose metabolism, metformin treatment was associated with higher AGE4. AGE4 positivity was significantly lower in gliptin-treated patients. Multivariate analysis showed that polyneuropathy and obesity were independently associated with AGE4 positivity, with odds ratios (ORs) of 0.21 and 3.02, respectively. Moreover, logistic regression showed that AGE4 positivity and HbA1c are independent predictors of polyneuropathy. Considering both indicators allows correct classification of 70.4% of cases with a general accuracy of 76%. CONCLUSIONS: The slot dot-blot method detects compounds found in serum in trace amounts. Accumulation of AGE4 was associated with glucose metabolism abnormalities. A tendency toward AGE4 positivity was less frequent in patients with microangiopathy and in non-treated and gliptin-treated diabetes patients.

Metabolites of the Nitric Oxide (NO) Pathway Are Altered and Indicative of Reduced NO and Arginine Bioavailability in Patients with Cardiometabolic Diseases Complicated with Chronic Wounds of Lower Extremities: Targeted Metabolomics Approach (LC-MS/MS).

OBJECTIVE: The status of metabolites of the nitric oxide (NO) pathway in patients with chronic wounds in the course of cardiometabolic diseases is largely unknown. Yet arginine supplementation and citrulline supplementation as novel therapeutic modalities aimed at increasing NO are tested. MATERIAL AND METHODS: Targeted metabolomics approach (LC-MS/MS) was applied to determine the concentrations of L-arginine, L-citrulline, asymmetric and symmetric dimethylarginines (ADMA and SDMA), and arginine/ADMA and arginine/SDMA ratios as surrogate markers of NO and arginine availability in ulnar and femoral veins, representing systemic and local levels of metabolites, in patients with chronic wounds in the course of cardiometabolic diseases (n = 59) as compared to patients without chronic wounds but with similar cardiometabolic burden (n = 55) and healthy individuals (n = 88). RESULTS: Patients with chronic wounds had significantly lower systemic L-citrulline and higher ADMA and SDMA concentrations and lower L-arginine/ADMA and L-arginine/SDMA as compared to healthy controls. The presence of chronic wounds in patients with cardiometabolic diseases was associated with decreased L-arginine but with increased L-citrulline, ADMA, and SDMA concentrations and decreased L-arginine/ADMA and L-arginine/SDMA. Serum obtained from the ulnar and femoral veins of patients with chronic wounds differed by L-arginine concentrations and L-arginine/SDMA ratio, both lower in the femoral vein. Wound etiology affected L-citrulline and SDMA concentrations, lower and higher, respectively, in patients with venous stasis, and the L-arginine/SDMA ratio-lower in venous stasis. The wound type affected L-arginine/ADMA and citrulline-lower in patients with ulcerations or gangrene. IL-6 was an independent predictor of L-arginine/ADMA, VEGF-A of ADMA, G-CSF of L-arginine/SDMA, and GM-CSF of L-citrulline and SDMA. CONCLUSION: Chronic wounds in the course of cardiometabolic diseases are associated with reduced NO and arginine availability due to ADMA and SDMA accumulation rather than arginine deficiency, not supporting its supplementation. Wound character seems to affect NO bioavailability and wound etiology-arginine bioavailability. Arginine concentration and its availability are more markedly reduced at the local level than the systemic level.

Impact of chronic wounds of various etiology on systemic profiles of key inflammatory cytokines, chemokines and growth factors, and their interplay.

BACKGROUND: Non-healing wounds are becoming a growing concern for public health as a result of their increasing prevalence in progressively aging societies. OBJECTIVES: The aim of this article is to evaluate the effects of wound etiology on a panel of circulating cytokines in patients with non-healing wounds of the lower extremities. MATERIAL AND METHODS: This prospective case-control study involved 104 individuals: healthy elderly people (n = 46) and patients with diabetes and/or cardiovascular disease (n = 58; among them 38 with chronic wounds of venous, ischemic or neurotrophic etiology). Selected serum cytokines - i.e. IL-1ß, IL-4, IL-6, IL-8, FGF-2, G-CSF, GM-CSF, MCP-1, MIP-1α, TNF-α, VEGF-A, and PDGF-BB - were measured using the Luminex platform. RESULTS: Compared to healthy elderly people, presence of diabetes and/or cardiovascular disease was associated with elevated IL-6, IL-8, MCP-1 and G-CSF while non-healing wounds coexisted with the increase in the levels of all examined cytokines/growth factors except for G-CSF and GM-CSF. Among diseased elderly people, having wounds was associated with increased levels of IL-1ß, IL-4, IL-6, IL-8, FGF-2, MIP-1α, PDGF-BB, and VEGF-A. Interleukin 1ß elevation was a sole independent predictor of chronic wounds with an odds ratio (OR) of 6.3. Cytokines in healthy seniors were loosely interrelated, while the levels of cytokines in diseased patients with wounds displayed a tight pattern of association. When stratified by their etiology, the association pattern for IL-6, IL-8, MCP-1, and VEGF-A was disrupted in neurotrophic wounds. CONCLUSIONS: The results presented herein may improve our understanding of the pathomechanisms which lead to chronic wounds and of the effects they exert on a systemic level, as well as providing potential targets for more effective therapies.

Experimental and bioinformatic approach to identifying antigenic epitopes in human α- and ß-enolases.

Human α- and ß-enolases are highly homologous enzymes, difficult to differentiate immunologically. In this work, we describe production, purification and properties of anti-α- and anti-ß-enolase polyclonal antibodies. To raise antibodies, rabbits were injected with enolase isoenzymes that were purified from human kidney (α-enolase) and skeletal muscle (ß-enolase). Selective anti-α- and anti-ß-enolase antibodies were obtained by affinity chromatography on either α- or ß-enolase-Sepharose columns. On Western blots, antibodies directed against human ß-enolase, did not react with human α-isoenzyme, but recognized pig and rat ß-enolase. To determine what makes these antibodies selective bioinformatic tools were used to predict conformational epitopes for both enolase isoenzymes. Three predicted epitopes were mapped to the same regions in both α- and ß-enolase. Peptides corresponding to predicted epitopes were synthesized and tested against purified antibodies. One of the pin-attached peptides representing α-enolase epitope (the C-terminal portion of the epitope 3 - S262PDDPSRYISPDQ273) reacted with anti-α-enolase, while the other also derived from the α-enolase sequence (epitope 2 - N193VIKEKYGKDATN205) was recognized by anti-ß-enolase antibodies. Interestingly, neither anti-α- nor anti-ß-antibody reacted with a peptide corresponding to the epitope 2 in ß-enolase (G194VIKAKYGKDATN206). Further analysis showed that substitution of E197 with A in α-enolase epitope 2 peptide lead to 70% loss of immunological activity, while replacement of A198 with E in peptide representing ß-enolase epitope 2, caused 67% increase in immunological activity. Our results suggest that E197 is essential for preserving immunologically active conformation in epitope 2 peptidic homolog, while it is not crucial for this epitope's antigenic activity in native ß-enolase.

Effect of tocopherol on biochemical blood parameters in pleuritis-induced rats treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin.

The aim of this study was to evaluate the effect of tocopherol on pleuritis-induced rats exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Rats were treated with a single TCDD dose of 5 µg/kg body weight (b.w.) and then for 3 weeks they were daily supplemented with tocopherol at a dose of 30 mg/kg b.w. The inflammation was initiated by intrapleural injection of a single dose of 1% carrageenin solution in a volume of 0.15 ml. Changes in biochemical blood parameters were measured three times at the 24th, 72nd and 120th hour of pleuritis and the blood was collected from 20 animals of each group of rats (group with the control inflammation; group treated with TCDD and with control inflammation; group treated with TCDD, supplemented with tocopherol and with the inflammation). The following biochemical parameters were measured: tumor necrosis factor (TNF), interleukin-1 (IL-1), IL-2, IL-4, IL-6, procollagen, telopeptide, fibrinogen, cholesterol, urea, creatinine, aspartate aminotransferase (AspAT) and alanine aminotransferase (AlAT). Daily supplementation of tocopherol caused significant changes in the level of TNF, IL-1, IL-4, IL-6, urea, creatinine, AspAT and AlAT. According to the results of these studies, we suggest that tocopherol supplementation in high doses could act as a protective treatment to improve liver metabolism.

Influence of dioxin intoxication on the human system and possibilities of limiting its negative effects on the environment and living organisms.

INTRODUCTION AND OBJECTIVE: Despite the restrictive legal regulations related to the reduction of dioxins emission, their concentration in the environment is still too high. Mainly, this is related to the illegal utilisation of electronic equipment and combustion of wastes, and also to intensified activity and maintenance of ships, especially in developing countries. The most important remaining source in Europe is the metal industry. Studies on the mechanism of impact of dioxins are still being carried out. This review points at new possibilities for limiting the molecular mechanisms of dioxins activity, inter alia, through the application of high doses of tocopherol and acetylsalicylic acid while treating dioxins intoxication. BRIEF DESCRIPTION OF THE STATE OF KNOWLEDGE: Apart from the knowledge of dioxins affinity to the aryl hydrocarbon receptor (AhR), the multi-stage radical-form actions and the pro-inflammatory mechanism associated with cyclooxygenase-II enzyme (COX-2) are under intense investigation at the moment. Due to the high affinity of dioxins to animals adipose tissue and their ability to accumulate in it, they can enter the food chain. Furthermore, high dioxin doses can cause poisoning manifested as advanced clinical symptoms, whereas in smaller doses, when cumulated, can cause metabolic changes which are often difficult to associate with their presence. Recently, some serious food contaminations by dioxins have been demonstrated. Sea fish and products from contaminated aqueducts still constitute potential sources of dioxins pollution. CONCLUSION: According to recent studies, dioxins are present in different concentrations in the environment and cause specific and long-time effects. These effects could be limited by the use of tocopherol and acetylsalicylic acid.

The influence of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on hematological parameters during experimentally induced pleuritis in rats.

Proper functioning of homeostatic mechanisms is characteristic for every healthy organism and enables adapting to environmental changes. These complicated systematic reactions can neutralize the harmful stress factors leading to various inflammatory reactions. The aim of this study was to determine dynamic changes in the inflammatory reaction after single 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) administration of 5 µg/kg body weight into rats with experimentally induced pleuritis. These changes were observed by monitoring the hematological blood parameters during inflammation. The obtained results proved that dioxins contribute to various changes in the character of the inflammatory response. TCDD administration before pleuritis initiation caused an increase of lymphocytes and significant decrease of the number of neutrophils during inflammation. The current study proved that administration of low TCDD dose (seven times lower than used in other studies) can cause thymus, spleen, or lymphatic gland atrophy. This finding indicates the toxic influence of small TCDD dose especially on the immune system.

Mechlorethamine (NTG) effects on the erythrocytic and leukocytic blood parameters during experimentally induced pleuritis in rats.

BACKGROUND: According to cytotoxic and mutagenic properties, nitrogranulogen (NTG) changes the character of inflammatory reactions. Our previous studies have shown that NTG can enhance immunological defense reactions, because of its high affinity to DNA, and causes disorders in the synthesis of acute phase proteins (e.g., haptoglobin, transferrin, fibrinogen and complement protein C3) [15]. The aim of the current studies was to determine the influence of three different NTG doses: 5 µg/kg b.w. (body weight), 50 µg/kg b.w. and 600 µg/kg b.w. (cytotoxic dose) on the values of hematological blood parameters: RBC, HGB, HCT, RDW, MCV, MCH, MCHC, PLT, MPV, PCT, PDW, WBC, NEUT, LYMPH, MONO, EOS and BASO in pleuritis-induced rats. METHODS: The animals were randomized into five groups: Group I - control group; Group II - IP (induced pleuritis) group; Group III - NTG5 group; Group IV - NTG50 group; Group V - NTG600 group. The blood was collected from all the groups at the 24(th) h, 48(th) h, and 72(nd) h after the initiation of the carrageenin-induced inflammatory reaction. RESULTS: These investigations have revealed that NTG administered at the dose of 5 µg/kg b.w. caused the drop of the leukocyte and lymphocyte numbers and the rise of the neutrophil number at the 72(nd) h of the experimental-induced inflammatory reaction. Moreover, the dose of: 5 µg/kg b.w. was an immunomodulatory property and it also increased the erythrocytic parameters. On the contrary, NTG applied at the doses of 50 µg/kg and 600 µg/kg b.w. contributed to the drop of both: the erythrocytic and leukocytic parameters during the whole time of the inflammatory reaction. CONCLUSIONS: The results suggest that nitrogranulogen affects the erythropoiesis.

Estimation of the action of three different mechlorethamine doses on biochemical parameters during experimentally induced pleuritis in rats.

Nitrogranulogen (NTG) may modify the character of inflammatory reactions. These modifications are a result of cytotoxic and mutagenic effects. NTG has high affinity to DNA and causes disorders in the synthesis of acute phase proteins (e.g., haptoglobin, transferrin, fibrinogen, and complement protein C3). Our previous studies have shown that small doses of NTG can enhance immunological defense reactions in the organism. The aim of the current studies was to determine how different NTG doses cause changes in the values of biochemical parameters in pleuritis-induced rats. The animals were randomized into five groups: Group I - control group; Group II - IP (induced pleuritis) group; Group III - NTG5 group; Group IV - NTG50 group; Group V - NTG600 group. Blood was collected from all groups of animals at 24, 48, and 72 h after the initiation of the carrageenin-induced inflammatory reaction. These investigations revealed that a dose of 5 µg NTG/kg b.w. (body weight) can change the character of the inflammation. Our studies also show that a dose of 600 µg NTG/kg b.w. causes a rapid decrease in the level of C3 at the 72 h of the experiment (after 3 applications every 24 h), which indicates a cytotoxic action of such a large NTG dose. NTG used at doses of 50 and 600 µg/kg b.w. causes the opposite metabolism of albumins and other serum proteins. Our studies show that the different doses of NTG have distinct effects on the inflammatory reaction.

Glycation of the muscle-specific enolase by reactive carbonyls: effect of temperature and the protection role of carnosine, pyridoxamine and phosphatidylserine.

Reactive carbonyls such as 4-hydroxy-2-nonenal (4-HNE), trans-2-nonenal (T2 N), acrolein (ACR) can react readily with nucleophilic protein sites forming of advanced glycation end-products (AGE). In this study, the human and pig muscle-specific enolase was used as a protein model for in vitro modification by 4-HNE, T2 N and ACR. While the human enolase interaction with reactive α-oxoaldehyde methylglyoxal (MOG) was demonstrated previously, the effect of 4-HNE, T2N and ACR has not been identified yet. Altering in catalytic function were observed after the enzyme incubation with these active compounds for 1-24 h at 25, 37 and 45 °C. The inhibition degree of enolase activity occurred in following order: 4-HNE > ACR > MOG > T2N and inactivation of pig muscle-specific enolase was more effective relatively to human enzyme. The efficiency of AGE formation depends on time and incubation temperature with glycating agent. More amounts of insoluble AGE were formed at 45 °C. We found that pyridoxamine and natural dipeptide carnosine counteracted AGE formation and protected enolase against the total loss of catalytic activity. Moreover, we demonstrated for the first time that phosphatidylserine may significantly protect enolase against decrease of catalytic activity in spite of AGE production.

[The composition, biochemical properties and toxicity of snake venoms]. / Sklad i wlasciwosci biochemiczne oraz toksycznosc jadów wezy.

2.5 million cases of snake bites are noticed in the world every year (within 100,000 is mortal). These bites occur frequently in Asia and Africa. Some reports proved the toxicity and composition changes of well-known venoms from the same snake species according to the climatic zone. Snake venom is a natural source of many biologically active substances, including those with potential therapeutic properties. These substances contain peptides, proteins, and enzymes which are divided into five subfamilies: three-finger toxins, serine protease inhibitors of the Kunitz type, phospholipases A2, serine proteases, and metalloproteases. All snake venoms are grouped depending on their mode of action. They usually cause neurotransmission disorders, cardiotoxic action, hemostasis disorders, and have central nervous system and necrotic activity.

[Amphibian skin secretions as a new source of antibiotics and biologically active substances]. / Substancje wydzielane przez gruczoly skórne plazów jako nowe zródlo antybiotyków i zwiazków biologicznie czynnych.

So far, the main sources of biologically active substances used in medicine have been plants, molds, and propolis. The obtained compounds have either therapeutic features or require additional modification. They are sometimes combined with other pharmacological substances to intensify their therapeutic effect. However, the effectiveness of many drugs has been rapidly decreasing.The overuse of antibiotics in the treatment and prophylaxis of human infections (especially in hospitals) as well as their widespread and often unjustified use in the treatment and prophylaxis of farm animal illnesses contribute to the development of a variety of resistance mechanisms by microorganisms. Because of the increasing ineffectiveness of antibiotics used so far and difficulties in obtaining new drugs, it is necessary to find new sources of these compounds, for example in animal organisms. Research has demonstrated that amphibian skin secretions are rich in a variety of active substances which have strong pharmacological properties. In these compounds we can distinguish, for example, toxins, antimicrobial peptides, opioid peptides, steroids, and alkaloids.These compounds show cytotoxic, antimicrobial, analgesic, anti-inflammatory, and even antiviral activities (including anti-HIV). These substances can be used in cell receptor studies and in transmembrane ion transport analysis. Because these compounds are secreted by skin glands,they can be easy obtained without injuring these animals. It is probable that amphibian skin constitutes a potential source of modern drugs.