Total Lactate Dehydrogenase Activity Research Articles

Biological effects of molybdenum(IV) sulfide nanoparticles and microparticles in the rat after repeated intratracheal administration.

In this study, molybdenum(IV) sulfide (MoS2 ) nanoparticles (97 ± 32 nm) and microparticles (1.92 ± 0.64 μm) stabilized with poly (vinylpolypyrrolidone) (PVP) were administered intratracheally to male and female rats (dose of 1.5 or 5mg/kg bw), every 14 days for 90 days (seven administrations in total). Blood parameters were assessed during and at the end of the study (hematology, biochemistry including glucose, albumins, uric acid, urea, high density lipoprotein HDL, total cholesterol, triglycerides, aspartate transaminase, and alanine transaminase ALT). Bronchoalveolar lavage fluid (BALF) analyses included cell viability, biochemistry (total protein concentration, lactate dehydrogenase, and glutathione peroxidase activity), and cytokine levels (tumor necrosis factor α, TNF-α, macrophage inflammatory protein 2-alpha, MIP-2, and cytokine-induced neutrophil chemoattractant-2, CINC-2). Tissues were subjected to routine histopathological and electron microscopy (STEM) examinations. No overt signs of chronic toxicity were observed. Differential cell counts in BALF revealed no significant differences between the animal groups. An increase in MIP-2 and a decrease in TNF-α were observed in BALF in the exposed males. The histopathological changes in the lung evaluated according to a developed classification system (based on severity of inflammation, range 0-4, with 4 indicating the most severe changes) showed average histopathological score of 1.33 for animals exposed to nanoparticles and microparticles at the lower dose, 1.72 after exposure to nanoparticles at the higher dose, and 2.83 for animals exposed to microparticles at the higher dose. In summary, it was shown that nanosized and microsized MoS2 can trigger dose-dependent inflammatory reactions in the lungs of rats after multiple intratracheal instillation irrespective of the animal sex. Some evidence indicates a higher lung pro-inflammatory potential of the microform.

Effects of fermented feed on growth performance, serum biochemical indexes, antioxidant capacity, and intestinal health of lion-head goslings.

The aim of this study was to evaluate the effects of fermented feed on growth performance, antioxidant indexes and intestinal health in lion-head goslings. 288 male lion-head goslings (one-day-old) were randomly divided into four groups (6 replicates per group, 12 samples per replicate): control group (basal diet) and fermented feed (FF) groups (basal diet supplemented with 2.5, 5.0 and 7.5% FF, respectively). The experimental period lasted 28 days. The results showed that 5.0 and 7.5% FF groups decreased feed conversion rate (FCR) when compared with the control group (p < 0.05). The 5.0% FF group reduced the activity of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) in serum; while the 7.5% FF group decreased the concentration of total cholesterol (TC), ALP and LDH activity (p < 0.05). Furthermore, the 7.5% FF group significantly increased total antioxidant capacity (T-AOC) in serum (p < 0.05); 2.5% and 5.0% FF groups significantly increased glutathione peroxidase (GSH-Px) in serum (p < 0.05); all FF groups increased the activity of superoxide dismutase (T-SOD) in serum (p < 0.05). For intestinal health, the villous height and villi/crypt ratio in jejunum were increased in all FF groups, but crypt depth was decreased (p < 0.05); The 5.0% FF groups enhanced T-AOC activity in jejunum (p < 0.05); The 2.5% and 5.0% FF groups enhanced GSH-Px activity (p < 0.05) in jejunum; All FF groups reduced malondialdehyde (MDA) level in jejunum (p < 0.05). LEfSe analysis showed that the cecum microbiota was significantly dominant in the 2.5% FF group compared to the control group including Firmicutes, Lactobacillales, Lactobacillus, and Prevotella; the flora that were significantly dominant in the 5.0% FF group compared to the control group included Bacteroidaceae, Bacteroides, Megamonas, and Prevotella; and the groups that were significantly dominant in the 7.5% FF group compared to the control group included Bacteroidota, Bacteroides, Bacteroidaceae, and Ruminococcaceae. In summary, dietary FF supplementation improved growth performance, serum biochemical parameters and antioxidant capacity of lion-head goslings, as well as improved jejunal tissue morphology and optimized intestinal flora structure. In particular, the FF addition at a dose of 7.5% was relatively more effective for lion- head goslings.

Dinoflagellate Karenia mikimotoi on the growth performance, antioxidative responses, and physiological activities of the rotifer Brachionus plicatilis.

The harmful dinoflagellate Karenia mikimotoi is responsible for the mortality of aquatic animals. However, the mechanism behind these toxic effects has not been fully determined. Herein, the toxic effects of K. mikimotoi on the growth performance, antioxidative responses, physiological activities, and energetic substance contents of rotifer Brachionus plicatilis were assessed. Rotifers were exposed to Nannochloropsis salina (Eustigmatophyceae), K. mikimotoi, and a mixture of N. salina and K. mikimotoi with biomass ratio proportions of 3:1, 1:1, and 1:3, respectively. Results indicated that K. mikimotoi negatively affected the population growth, survival, and specific growth rates of rotifers within 24 h. The level of reactive oxygen species (ROS), the content of malondialdehyde, and the activity of amylase increased. However, the total antioxidant capacity level, pepsase, cellulase, alkaline phosphatase, xanthine oxidase, and lactate dehydrogenase activities, and glycogen and protein contents decreased with increasing proportions of K. mikimotoi. The mixture of 50% N. salina and 50% K. mikimotoi promoted the increase in glutamic-pyruvic transaminase activity and triglyceride content. These findings underscore ROS-mediated antioxidative responses, physiological responses, and energetic substance content changes in B. plicatilis work together to affect population dynamics inhibition of rotifers by K. mikimotoi.

Biochemical responses of the giant clam (Tridacna squamosa Lamarck, 1819) and the burrowing sea urchin (Echinometra mathaei (de Blainville, 1825)) to spatial and seasonal variations on the Red Sea coast of Egypt

This study aims to investigate the spatial and seasonal impacts on the biochemical responses of two bioindicators: Tridacna squamosa and Echinometra mathaei which inhabit the Red Sea coast of Egypt. Samples were collected from three sites during the summer of 2019 and the winter of 2020. Total protein, MDA, and enzyme activity of pyruvate kinase (PK) and lactate dehydrogenase (LDH) were measured in the gonads of the collected samples. The results confirmed that environmental variables vary at both spatial and seasonal levels, where the two species exhibited different patterns of biochemical response to internal and external stresses. In addition, both studied species did not resort to anaerobic respiration as a defense mechanism. Therefore, this study confirms that the use of biomarkers in the field shall be regarded as a general warning of internal and external stress.

C57Bl/6N mice have an attenuated lung inflammatory response to dsRNA compared to C57Bl/6J and BALB/c mice

BackgroundLower respiratory infections caused by ssRNA viruses are a major health burden globally. Translational mouse models are a valuable tool for medical research, including research on respiratory viral infections. In in vivo mouse models, synthetic dsRNA can be used as a surrogate for ssRNA virus replication. However, studies investigating how genetic background of mice impacts the murine lung inflammatory response to dsRNA is lacking. Hence, we have compared lung immunological responses of BALB/c, C57Bl/6N and C57Bl/6J mice to synthetic dsRNA.MethodsdsRNA was administered intranasally to BALB/c, C57Bl/6N and C57Bl/6J mice once/day for three consecutive days. Lactate dehydrogenase (LDH) activity, inflammatory cells, and total protein concentration were analyzed in bronchoalveolar lavage fluid (BALF). Pattern recognition receptors levels (TLR3, MDA5 and RIG-I) were measured in lung homogenates using RT-qPCR and western blot. Gene expression of IFN-β, TNF-α, IL-1β and CXCL1 was assessed in lung homogenates by RT-qPCR. ELISA was used to analyze protein concentrations of CXCL1 and IL-1β in BALF and lung homogenates.ResultsBALB/c and C57Bl/6J mice showed infiltration of neutrophils to the lung, and an increase in total protein concentration and LDH activity in response to dsRNA administration. Only modest increases in these parameters were observed for C57Bl/6N mice. Similarly, dsRNA administration evoked an upregulation of MDA5 and RIG-I gene and protein expression in BALB/c and C57Bl/6J, but not C57Bl/6N, mice. Further, dsRNA provoked an increase in gene expression of TNF-α in BALB/c and C57Bl/6J mice, IL-1β only in C57Bl/6N mice and CXCL1 exclusively in BALB/c mice. BALF levels of CXCL1 and IL-1β were increased in BALB/c and C57Bl/6J mice in response to dsRNA, whereas the response of C57Bl/6N was blunt. Overall, inter-strain comparisons of the lung reactivity to dsRNA revealed that BALB/c, followed by C57Bl/6J, had the most pronounced respiratory inflammatory responses, while the responses of C57Bl/6N mice were attenuated.ConclusionsWe report clear differences of the lung innate inflammatory response to dsRNA between BALB/c, C57Bl/6J and C57Bl/6N mice. Of particular note, the highlighted differences in the inflammatory response of C57Bl/6J and C57Bl/6N substrains underscore the value of strain selection in mouse models of respiratory viral infections.

Determination of the effect of iatrogenic blood contamination on lactate dehydrogenase and creatine kinase activity in canine cerebrospinal fluid.

Lactate dehydrogenase (LDH) and creatine kinase (CK) have differential tissue activity and isoenzyme profiles. LDH and CK exist as 5 and 3 isoenzymes, respectively, in both serum and cerebrospinal fluid (CSF). Studies have demonstrated that measuring LDH, CK, and their isoenzymes in CSF has diagnostic and prognostic values for dogs and people with neurologic disorders. Iatrogenic blood contamination can distort the results of CSF analysis. The purpose of this study was to determine allowable thresholds of blood contamination (RBC/μL) for accurate measurement of LDH, CK, and their isoenzymes in canine CSF. Venous blood and CSF were collected from healthy dogs. Total LDH and CK activity were measured spectrophotometrically. Isoenzyme profiles were determined using gel electrophoresis and densitometric scanning. All samples were analyzed within 6hours of collection. A nonlinear mixed effects regression model was used to estimate the allowable thresholds of blood contamination for accurate measurement of LDH, CK, and their isoenzymes in canine CSF. The threshold of iatrogenic blood contamination for total LDH and total CK in healthy dogs are 6696 RBC/μL (95% CI 3879-11 187) and 5961 RBC/μL (95% CI 2939-12 085), respectively. LDH-1 is the most sensitive isoenzyme to iatrogenic blood contamination, while LDH-4 is the least sensitive. These results are important for the interpretation of LDH, CK, and their isoenzymes in canine CSF. Additionally, our methodology is translatable for determining thresholds of acceptable iatrogenic blood contamination in CSF for other diagnostic and prognostic biomarkers of neurologic disease.

Association between Calprotectin and Cystatin C levels with kidney injury Molecule-1 and their effects on developments of COVID-19 complications

Objectives: This work aimed to study the association between KIM-1, Calprotectin and Cystatin C and other biomarkers and their roles for early detection of the severity of Covid-19 associated with kidney injury complications that lead to death in severe Covid- 19 patients.&#x0D; Methods: This study included 91 samples patients with Covid-19 divided into two group, 46 patients of them with severe Covid-19 and 45 patients of them with moderate infected Covid-19 include (56 male, 35 female) with a matched age ranged between (22-88) years patients. The study was conducted from Al-hayat unit, Al-Hussein Teaching Hospital, Al-Hussein Medical City during the period from (Oct., 2020 to July., 2021). The biomarkers determined include: ferritin, C-reactive protein (CRP), total lactate dehydrogenase (LDH) activity, creatinine, urea, cystatin C (Cys C), calprotectin (CLP), and kidney injury molecule-1 (KIM-1) beside complete blood count test (CBC) which were determined by using various biochemical techniques including ELISA. Results: The results of data which include 46 patients with severe Covid-19 group and another 45 patients with moderate Covid-19 infection, there is significant data obtained for ferritin, LDH and RDW-CV when compare between severe and moderate group of Covid-19 patients (p&lt;0.05) while other parameter showed a non-significant increased result. There is positive correlation between KIM-1 and Cys C in severe and moderate group (p&lt; 0.01) and with creatinine (p&lt;0.01) and urea (p&lt;0.05) in severe Covid-19 group, and significant correlation between Cys C and creatinine in severe group (p&lt;0.05).&#x0D; Conclusion: There is a significant correlation between KIM-1 and CysC and serum creatinine with Cys. C and KIM-1. Also, the obtained results illustrated that CLP, Cys C and KIM-1were non-significant increase in Covid-19 patients groups, but ferritin and LDH had increment significantly when compare between severe and moderate group and can be served as parameter predictor and increased mortality risk for Covid-19 patients.

Biochemical Studies on the Colorectal Tissues of Wistar Rats Treated with Methanol Leaf and Stem Bark Extracts of Annona muricata (Soursop).

Annona muricata(AMC), is a tropical plant species of theAnnonaceaefamily known for its medicinal uses in ameliorating and/or protecting several organs and tissues in the body. In this study we elucidated the influence of the methanol extracts of AMC leaf and stem bark on the biochemical and histological integrity of the colorectum. Different doses (100, 200, 400, 600, and 800mg of extract/kg body weight) of methanol extracts of the leaves and stembark were orally administered to adult male Wistar rats of average weight (100 - 150 g) for 28 days. At the end of the experimental period, the rats were sacrificed and colorectal tissues harvested for analyses. Adenosine triphosphatase (ATPases), lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G6PD) activities, and tissue protein (TP) concentration, were evaluated by colorimetric method using appropriate test kits.The results in the colorectal tissue analysed showed that total ATPase, LDH and G6PD (energy markers) activities increased significantly in the groups which received methanol leaf and stem bark extracts of AMC when compared with control. However, a general decrease was observed in TP and Na+/K+-ATPase activity but there was a twist in Na+/K+-ATPase activity in stem bark doses of 200mg/kg and 400mg/kg which showed significant increases in dose dependent manner when compared with the control. Even though G6PD activity showed fluctuating patterns for both extracts, the highest dose (800mg/kg) reflected the most significant increase when compared with the control. The histology confirmed the toxicological results by the biochemical parameters. Under the condition of this study, we inferred that the methanol leaf and stem-bark extracts of AMC may significantly influence the enzymes by reducing and increasing total ATPase and Na+/K+-ATPase activities depending on the doses and administration should therefore depend on the desired outcome.

Influence of Microplastics on the Development of Proteus Biofilm

Currently, research on the effects of microplastics (MPs) in biofilms has mainly been focused on the mature biofilm communities, with a lack of sufficient details on the influence on different development stages of biofilms. Proteus and 1 μm polystyrene microplastics (PS-MPs), which are widely found in the environment, were selected as the research objects to explore the effects of microplastics on biofilms at different developmental stages. In our study, the effects of PS-MPs on biofilm biomass, extracellular polymer composition(EPS), and extracellular enzyme activity were investigated using an exposure test. Our results showed that the effect of PS-MPs on biofilms at different stages was similar, but the effect was significantly reduced with the development of biofilms. Biofilms at different development stages had different sensitivities to microplastics. In the reversible attachment stage, the no observed effect concentration (NOEC) of EPS composition, reactive oxygen species (ROS) production, and extracellular enzyme activity were significantly lower than those in other stages; however, the NOEC of total antioxidant capacity (T-AOC) and lactate dehydrogenase (LDH) activity were similar. This may be the result of ROS-mediated protein oxidation, which can be reduced but not completely eliminated by EPS in other stages of biofilm. This indicates that PS-MPs has a low toxic effect on biofilm.

INFLUENCE OF HEAVY METALS ON ANTIOXIDANT SYSTEM AND BIOCHEMICAL INDEXES IN RATS

The study was undertaken to examine the effect of heavy metals on antioxidant system and biochemical indexes in the organism of rats. The influence of heavy metals on indexes The influence of heavy metals on the indicators of the antioxidant system (activity of the antioxidant system enzymes – glutathione peroxidase, glutathione reductase, catalase, and superoxide dismutase) and the processes of lipid peroxidation (content of hydroperoxides and products of thiobarbituric acid) was determined. It is established, that the antioxidant system functions more intensively in blood and liver of rats under the action of heavy metals. The study of enzyme activity showed the activation of the latter under conditions of heavy metal intoxication in 1.5–2.0 times (depending on heavy metal) compared with the control. We found that blood levels of total and direct bilirubin, creatinine, and urea increased in intoxicated rats from all experimental groups compared with intact animals. However, a decrease in the content of albumin, total protein, cholesterol, and triglycerides was also found in all experimental groups, in comparison with intact rats. Under the action of heavy metals, the activity of total α-amylase, lactate dehydrogenase, and glucose concentration increases in blood of rats. According to the results of studies in intoxicated animals compared with the intact group, there was a change in the cation-anion pool, in particular, a tendency to decrease the content of sodium and inorganic phosphorus and increase chlorides, magnesium, calcium, and potassium.

Hepatotoxicity induced by intravenous administration of PEGylated nano-graphene oxide in albino mice

Graphene oxide (GO) has been intensely investigated in recent years due to its biocompatibility and its role in drug delivery. Its conjugation with polyethylene glycol (PEG) further improves its solubility in physiological solutions, which is important for enhancing efficacy of drug delivery. The present study aimed to assess the hepatotoxicity of PEG-nGO in mature mice. Liver function tests such as Alanine transferase (ALT), Alkaline phosphatase (ALP) were performed in the liver homogenate of the control and treated groups after intravenous administration of a single dose (5 mg/kg) of PEG-nGO through the tail vein. Total Glycogen content and lactate dehydrogenase (LDH) activity was measured. For histology studies, liver slices were fixed in 10% formalin and stained with H&amp;E and photographed. The liver function test indicated a significant increase in ALT and ALP activity following 1 to 2 h of treatment with PEG-nGO, which recovers to normal levels at 4 h. Total glycogen contents were mobilized from the liver in the first hour in response to stress, which again regain normality after 4 h. The LDH assay showed maximum necrosis and apoptosis of hepatocytes at 1 h. Histology studies further indicated that infiltration of inflammatory cells and vacuolization of cytoplasm occurred mostly at 1 h. PEG-nGO treatments caused maximum damage and toxicity to the liver during the first 2 h. Following this, the liver tissues recover substantially which indicated that the low dose toxicity of PEG-nGO to the liver was transient and reversible.

Coxsackievirus A2 Leads to Heart Injury in a Neonatal Mouse Model.

Coxsackievirus A2 (CVA2) has emerged as an active pathogen that has been implicated in hand, foot, and mouth disease (HFMD) and herpangina outbreaks worldwide. It has been reported that severe cases with CVA2 infection develop into heart injury, which may be one of the causes of death. However, the mechanisms of CVA2-induced heart injury have not been well understood. In this study, we used a neonatal mouse model of CVA2 to investigate the possible mechanisms of heart injury. We detected CVA2 replication and apoptosis in heart tissues from infected mice. The activity of total aspartate transaminase (AST) and lactate dehydrogenase (LDH) was notably increased in heart tissues from infected mice. CVA2 infection also led to the disruption of cell-matrix interactions in heart tissues, including the increases of matrix metalloproteinase (MMP)3, MMP8, MMP9, connective tissue growth factor (CTGF) and tissue inhibitors of metalloproteinases (TIMP)4. Infiltrating leukocytes (CD45+ and CD11b+ cells) were observed in heart tissues of infected mice. Correspondingly, the expression levels of inflammatory cytokines in tissue lysates of hearts, including tumor necrosis factor alpha (TNF-α), interleukin-1beta (IL-1β), IL6 and monocyte chemoattractant protein-1 (MCP-1) were significantly elevated in CVA2 infected mice. Inflammatory signal pathways in heart tissues, including phosphatidylinositol 3-kinase (PI3K)-AKT, mitogen-activated protein kinases (MAPK) and nuclear factor kappa B (NF-κB), were also activated after infection. In summary, CVA2 infection leads to heart injury in a neonatal mouse model, which might be related to viral replication, increased expression levels of MMP-related enzymes and excessive inflammatory responses.

Plasma LDH: A specific biomarker for lung affectation in COVID-19?

ObjectivesWe aimed to determine whether the plasma profile of lactate dehydrogenase (LDH) isoenzymes is altered in patients with COVID-19, and whether this is attributable to a specific release of LDH-3, the main LDH isoenzyme expressed in lungs. DesignWe collected fresh plasma aliquots from 17 patients (LDH range, 281–822 U/L) and seven controls (LDH ​< ​230 U/L). In-gel relative activity of the different LDH isoenzymes was determined by electrophoresis and densitometric analysis. ResultsDespite the expected higher total LDH activity levels in patients (p ​< ​0.001), the in-gel relative activities of LDH isoenzymes did not differ between patients and controls (all p ​> ​0.05). We found no correlation between total plasma LDH activity and the in-gel relative activities of the different LDH isoenzymes, including LDH-3. Likewise, there was no correlation between LDH-3 and various routine haematological and serum parameters that have been previously reported to be altered in COVID-19 (such as lymphocyte count, albumin, alanine and aspartate aminotransferase, creatinine, C-reactive protein, or ferritin). ConclusionsOur findings suggest that elevation of plasma LDH activity in patients with COVID-19 is not associated to a specific release of LDH-3 into the bloodstream, and do not support the use of LDH as a specific biomarker for lung affectation in patients with COVID-19.

Activity of alkaline phosphataseand total lactate dehydrogenase in blood of patients with hypertension depending on solar activity and variantsof antihypertensive therapy

Activity of alkaline phosphataseand total lactate dehydrogenase in blood of patients with hypertension depending on solar activity and variantsof antihypertensive therapy

Lactate dehydrogenase as a predictor of bronchiolitis severity in children in teaching hospitals in Egypt

Background: Bronchiolitis is a common lower respiratory tract infection in infants. Lactate Dehydrogenase (LDH) may be a useful biomarker to assist its severityAim of current study was to study the efficacy of LDH in both nasal secretions (NW-LDH) and serum (S-LDH) as a useful biochemical indicator of bronchiolitis severity .Subject and Methods: The present study was conducted on 96 infant with bronchiolitis ( < 24 months old ) presenting to pediatric department of Al-ahrar and Ahmed Maher Teaching Hospital. during the period from November 2018 to March 2019. Patients were subjected to history taking, clinical examination general and systemic, investigations including blood gases &CRP, chest X –ray if necessary, total LDH activity in both nasal secretions and serum. Results: In bronchiolitis, percentage of male was higher than female (65.6%, 34.4 %), with a mean ±SD of age 8.25±2.61 months, percentage of mild , moderate and severe cases were 36 (37.5%) , 44(45.8 %) ,16 (16.7%) respectively. No significant difference in serum LDH(S-LDH) between mild cases not admission moderate require hospital admission or severe cases require PICO admission (F:1.46 P: 0.237) while there was significant difference in nasal wash LDH (NW-LDH) among different grades of severity (F: 70.85 ,P:0.001) The significant predictors for severity of bronchiolitis were NW-LDH , younger age , longer hospital stay ,. Conclusion: NW-LDH is a biochemical Predictor of bronchiolitis severity , hospital ,PICO admission than S-LDH if demographic variable and viral etiology are taken in consideration

Lemon Exosome-like Nanoparticles-Manipulated Probiotics Protect Mice from C.d iff Infection.

SummaryClostridioides difficile (C. diff) is the leading cause of antibiotic-associated colitis. Here, we report that lemon exosome-like nanoparticles (LELNs) manipulated probiotics to inhibit C. diff infection (CDI). LELN-manipulated Lactobacillus rhamnosus GG (LGG) and Streptococcus thermophilus ST-21 (STH) (LELN-LS) decrease CDI mortality via an LELN-mediated increase in bile resistance and gut survivability. LELN-LS treatment increases the AhR ligands indole-3-lactic acid (I3LA) and indole-3-carboxaldehyde (I3Ald), leading to induction of IL-22, and increases lactic acid leading to a decrease of C. diff fecal shedding by inhibiting C. diff growth and indole biosynthesis. A synergistic effect between STH and LGG was identified. The STH metabolites inhibit gluconeogenesis of LGG and allow fructose-1,6-bisphosphate (FBP) to accumulate in LGG; accumulated FBP then activates lactate dehydrogenase of LGG (LGG-LDH) and enhances production of lactic acid and the AhR ligand. Our findings provide a new strategy for CDI prevention and treatment with a new type of prebiotics.

Contribution of Pulmonary CYP-mediated Bioactivation of Naphthalene to Airway Epithelial Injury in the Lung

Previous studies have established that cytochrome P450 enzymes (CYPs) in both liver and lung are capable of bioactivating naphthalene (NA), an omnipresent air pollutant and possible human carcinogen, in vitro and in vivo. The aim of this study was to examine the specific contribution of pulmonary CYPs in airway epithelial cells to NA-induced airway toxicity. We used a lung-Cpr-null mouse model, which undergoes doxycycline-induced, Cre-mediated deletion of the Cpr (a redox partner of all microsomal CYPs) gene specifically in airway epithelial cells. In 2-month-old lung-Cpr-null mice, Cpr deletion occurred in 75%-82% of epithelial cells of conducting airways. The extent of NA-induced acute lung toxicity (as indicated by total protein concentration and lactate dehydrogenase activity in bronchoalveolar lavage fluid collected at 24-h after initiation of a 4-h, nose-only, 10-ppm NA inhalation exposure) was substantially lower (by 37%-39%) in lung-Cpr-null mice, compared with control littermates. Moreover, the extent of cellular proliferation (as indicated by 5-bromo-2'-deoxyuridine incorporation) was noticeably lower in both proximal and distal airways (by 59% and 65%, respectively) of NA-treated lung-Cpr-null mice, compared with control littermates, at 2-day post-NA inhalation exposure. A similar genotype-related difference in the extent of postexposure cell proliferation was also observed in mice exposed to NA via intraperitoneal injection at 200 mg/kg. These results directly validate the hypothesis that microsomal CYP enzymes in airway epithelial cells play a large role in causing injury to airway epithelia following exposure to NA via either inhalation or intraperitoneal route.

The influence of selenium deficiency on chosen biochemical parameters and histopathological changes in muscles of goat kids.

The research was conducted on 40 young alpine goats (kids) divided into two groups. First group consisted of 20 kids demonstrating clinical signs of muscular dystrophy. Second group was a control and consisted of 20 animals that received intramuscular injection (2ml per animal) of vitamin E and selenium preparation containing in 1ml 50 mg of tocopherol acetate, 0.5mg of sodium selenite and solvent on 2nd day of life. The kids were clinically examined and blood for laboratory analyses was sampled three times from day 5 of their life in 10 day intervals. In addition, six 24 days old kids demonstrating clinical signs of muscular dystrophy and six control kids were subjected to biceps femoris biopsy. Serum total protein, glucose, triglycerides, cholesterol as well as AST, CK and LDH were determined in all the animals. In addition, the activity of glutathione peroxidase (GSH-Px) was determined in whole blood and serum concentrations of selenium and vitamin E were deter-mined in 6 kids from each group. Total lactate dehydrogenase activity and its separation into isoenzymatic fractions were determined in the collected biopsy material. The muscle samples collected were additionally subjected to histopathological examination consisting of HE staining and HBFP staining to detect necrotic muscle fibers. Symptoms of muscular dystrophy began to appear in the first group between 17 and 23 days of age and included tremors of the limbs, poor posture, stilt gait and increased time of laying. The control animals did not show any symptoms of the disease during the experiment. Hypo-proteinemia, hypoglycemia, cholesterol reduction and elevated triglycerides level associated with lipolysis of adipose tissue have been found in the sick kids. A significant decrease in selenium, vitamin E and activity of glutathione peroxidase levels was observed in the kids with symptoms of muscular dystrophy. The activity of AST, CK and LDH was significantly higher in the animals with symptoms of the disease as well. Five isoenzymes were obtained in the electrophoretic separation of lactate dehydrogenase into isoenzymatic fractions in the muscle tissue. LDH4and LDH5 isoenzymes were dominating, and a significant increase in LDH5 fraction of the sick animals was also observed. Histopathological examination of muscle samples from sick animals revealed changes characteristic for the presence of Zenker necrosis.

Clinical and Diagnostic Significance of Lactate Dehydrogenase and Its Isoenzymes in Animals.

Lactate dehydrogenase (LDH) is widely distributed enzyme in cells of various living systems where it is involved in carbohydrate metabolism catalyzing interconversion of lactate and pyruvate with NAD+/NADH coenzyme system. Cells of tissues are direct source of lactate dehydrogenase isoenzymes that are naturally distributed in blood plasma/serum of animals and humans producing characteristic profile. This profile depends on intracellular isoenzyme concentration in all tissues that contribute to the common pool of lactate dehydrogenases in plasma/serum as a consequence of natural cell degradation. LDH is widely distributed in the body, high activities are found in the heart, liver, skeletal muscle, kidney, and erytrocytes, whereas lesser amounts are found in the lung, smooth muscle, and brain. Because of its widespread activities in numerous body tissues, LDH is elevated in a variety of disorders. There are many conditions that contribute to increased activity of LDH. An elevated total LDH value is a rather nonspecific finding. Therefore, LDH assays assume a more clinical significance when separated into isoenzyme fractions. The activity of LDH and its serum and tissue patterns and composition show great variations between the species. These differences do not allow using catalytic activities of LDH isoenzymes from one species to another. Instead, the pattern of serum LDH isoenzymes should be interpreted in respect to its species origin that is important in particular in veterinary medicine. Determination of total LDH activity and its isoenzyme pattern in serum of mammals had become one of the biochemical indicators in the assessment of organ disorders. When the content of cells is released from tissue to plasma, as on cell injury, the LDH isoenzyme pattern of the serum changes in favour of the profile of the affected organ (tissue) that can be used in the diagnostic practice.

Genotoxicity and oxidative damage in zebrafish (Danio rerio) after exposure to effluent from ethyl alcohol industry

In this research, the toxicological effect of untreated wastewater from of ethyl alcohol industry was evaluated on the zebrafish (Danio rerio) under experimental conditions. Fish were treated with zero, half, one and two percent of sewage effluent for 21 days. Toxic effects were monitored in liver by determining biochemical indicators, oxidative stress biomarkers, and the expression of genes involved in the detoxification. Results showed that Sod1, Gstp-1a, Gpx1a gene expressions were significantly increased in the hepatocytes after 21 days at 2.0% sewage exposure. Sewage exposure also significantly increased Gsr, Ces2 and Cyp1a, Mt1 and Mt2 gene expression in the hepatocytes of zebrafish as compared to the reference group (P < 0.01). Total cellular antioxidants, malondialdehyde (MDA) levels, aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP) activities in fish exposed to 1 and 2% of sewage were significantly higher than the control group (P < 0.01), whereas alanine aminotransferase (ALT) was only increased in fish exposed to 2% sewage (P < 0.01). A significant decrease in gamma-glutamyl-transferase (GGT) activity in fish exposed to 2% effluent was found (P < 0.01). Catalase (CAT) activity was increased in zebrafish exposed to all concentrations of effluent. The transcriptional analysis of the detoxification-related genes and the changes in the biochemical indicators evidenced that drainage of sewage effluents from the ethyl alcohol company is a serious threat to the health of aquatic animals in the Khorram-Rood River. These results will contribute to further study on the impact of sewage effluents of the alcohol industry on aquatic organisms.