Introduction: Antimicrobial peptides (AMP) are a large group of innate immune effectors, which apart from antimicrobial activity show immunomodulative properties. Platelet-rich plasma (PRP) is a source of autologous growth factors and is used for stimulation of bone and soft tissue healing. The purpose of this study was to assess the influence of PRP and AMP extract on ovine monocyte-derived macrophage cultures. Material and Methods: The study was conducted on ovine macrophages (Mfs) previously stimulated with LPS or dexamethasone and then with preparations of PRP or AMP. Following activation of the Mfs their morphological and functional features were assessed. Results: The study revealed pro-inflammatory influence of both examined preparations on Mfs cultures on the basis of morphology, ROS generation and arginase activity. Both preparations enhanced the pro-inflammatory response of cultured Mfs. Conclusion: This activity may intensify the antimicrobial action of Mfs, however, in cases of excessive and prolonged inflammation the use of these preparations should be limited.

For many years, scientists have been pursuing research on skeletal muscle ageing both in humans and animals. Studies on animal models have extended our knowledge of this mechanism in humans. Most researchers agree that the major processes of muscle ageing occur in the mitochondria as the major energy production centres in muscle cells. It is believed that decisive changes occur at the enzymatic activity level as well as in protein synthesis and turnover ability. Deregulation of ion channels and oxidative stress also play significant roles. In particular, in recent years the free radical theory of ageing has undergone considerable modification; researchers are increasingly highlighting the partly positive effects of free radicals on processes occurring in cells. In addition, the influence of diet and physical activity on the rate of muscle cell ageing is widely debated as well as the possibility of delaying it through appropriate physical exercise and diet programmes. Numerous studies, especially those related to genetic processes, are still being conducted, and in the near future the findings could provide valuable information on muscle ageing. The results of ongoing research could answer the perennial question of whether and how we can influence the rate of ageing both in animals and humans.

Introduction: Peroxiredoxin 6 (Prdx6) is a bifunctional protein with glutathione peroxidase activity and phospholipase A2 activity. Previous studies have shown a significant positive correlation between the intracellular survival ability of Brucella and Prdx6. Here, the Prdx6 enzyme with a single activity was constructed to facilitate study of the relationship between the single function of Prdx6 and Brucella infection. Material and Methods: The target open reading frame (ORF) DNAs of Prdx6 with a single active centre were prepared using gene splicing by overlap extension PCR (SOE-PCR), and the recombinant eukaryotic expression plasmids inserted by Prdx6 with the single activity centre were constructed and transfected into murine Raw264.7 macrophages. The glutathione peroxidase activity and phospholipase A2 activity of the constructed Prdx6 were examined. Results: The core centres (Ser³² and Cys⁴⁷) of Prdx6 were successfully mutated by changing the 94ᵗʰ nucleotide from T to G and the 140ᵗʰ nucleotide from G to C in the two enzyme activity cores, respectively. The constructed recombinant plasmids of Prdx6 with the single active centre were transfected into murine macrophages showing the expected single functional enzyme activity, which MJ33 or mercaptosuccinate inhibitors were able to inhibit. Conclusion: The constructed mutants of Prdx6 with the single activity cores will be a benefit to further study of the biological function of Prdx6 with different enzyme activity.

The aim of this study was to evaluate potential protective effects of propolis on furan-induced hepatic damage by assessing the levels of malondialdehyde (MDA) and reduced glutathione (GSH), antioxidant enzyme activities, and histopathological changes in the liver. Albino Wistar rats were divided into six groups: a control, propolis-treated (100 mg/kg b.w./day), low-dose furan-treated (furan-L group; 2 mg/kg b.w./day), high-dose furan-treated (furan-H group; 16 mg/kg b.w./day), furan-L+propolis treated, and furan-H+propolis treated group. Propolis and furan were applied by gavage; propolis for 8 days, and furan for 20 days in furan-L groups and 10 days in furan-H groups. While MDA levels were elevated in furan-treated groups, levels of GSH and activities of antioxidant enzymes decreased (p < 0.001). The levels of MDA and GSH and activities of antioxidant enzymes were normal in the furan+propolis groups, especially in the furan-L+propolis group (p < 0.001). While the aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate pdehydrogenase activities were elevated in the furan-H treated group (p < 0.05 and p < 0.001), they were unchanged in the furan-L treated group. Histopathologically, several lesions were observed in the liver tissues of the furan-treated groups, especially in the higher-dose group. It was determined that these changes were milder in both of the furan+propolis groups. The results indicate that propolis exhibits good hepatoprotective and antioxidant potential against furan-induced hepatocellular damage in rats.

Introduction: A model of fatty liver in postpartum sheep was established to measure blood paraoxonase 1 (PON1) and other biochemical indicators, which were used to predict fatty liver in sheep. Material and Methods: Sheep were assigned into two experimental groups: a fatty liver group (T, n = 10) and a healthy control group (C, n = 5). PON1 enzyme activity towards paraoxon as a substrate was quantified spectrophotometrically. The results were analysed by t-test and pearson correlation coefficient. Disease was predicted by binary logistic analysis, and diagnostic thresholds were determined by receiver operatingcharacteristic (ROC) analysis. Results: The activity of serum PON1 in group T was significantly decreased (P < 0.05) when compared with C group, and liver lipid content and the levels of serum BHBA, NEFA, and TG were significantly increased (P < 0.05). Thresholds were lower than 74.0 U/mL for PON1, higher than 0.97 mmol/L for β-hydroxybutyrate, higher than 1.29 mmol/L for non-esterified fatty acids, higher than 0.24 mmol/L for triglycerides, and lower than 71.35 g/L for total protein. Conclusion: This study verified that PON1, BHBA, NEFA, TG, and TP could be used to predict the risk of fatty liver in sheep.

This study was designed to evaluate the antioxidative status of serum by measuring its total antioxidant capacity, as well as the antioxidant enzyme activity (superoxide dismutase, catalase, and glutathione reductase), in dogs with various stages of degenerative mitral valve disease (DMVD) compared to healthy controls. In total, 71 client-owned dogs in different stages of DMVD, which included healthy controls, took part in the study. Following an anamnesis, clinical examination, standard transthoracic echocardiograpic examination, chest X-ray, complete blood (cell) count, and serum biochemistry, dogs were divided into 2 study groups. Blood was drawn from each dog once at the time of presentation and selected antioxidant parameters were measured using commercially available assay kits. The activity of superoxide dismutase gradually decreased in the more advanced stages of DMVD, while the activity of catalase was significantly higher in the group of dogs with asymptomatic DMVD compared to healthy controls and dogs with symptomatic DMVD. No significant changes were noted in total antioxidant capacity and the activity of glutathione reductase. Results suggested that DMVD has a significant impact on the activity of superoxide dismutase and catalase in the serum of the tested dogs. Knowledge of changes in the activity of antioxidative enzymes may warrant further studies, possibly to evaluate the potential role of compounds with antioxidative properties in the clinical outcome of dogs with DMVD.

OBJECTIVE To investigate effects of storage duration and temperature on biochemical analytes in plasma from red-eared sliders (Trachemys scripta elegans). ANIMALS 8 red-eared sliders. PROCEDURES Blood samples were collected. Plasma was harvested and analyzed at room temperature (approx 23°C; time = 1 hour) and then fractioned into 0.1-mL aliquots that were stored at room temperature or were refrigerated (4°C) or frozen (−20°C). Biochemical analysis of stored samples was performed at 4 (room temperature), 8 (4°C), 24 (4°C), 48 (4° and −20°C), and 72 (−20°C) hours and at 7 days (−20°C). For each time point for each storage temperature, bias was calculated by subtracting values from the value obtained at 1 hour. Bias was modeled by use of a linear mixed model. RESULTS Storage temperature had a significant effect on several plasma biochemical analytes. In general, aspartate aminotransferase activity and uric acid, total protein, and potassium concentrations increased after storage at 4° and −20°C. Differences in values after storage were mostly within the acceptable range for allowable total error, except for calcium and potassium concentrations for samples stored at −20°C. Both storage temperatures increased variability of measurement results. Results for samples stored at room temperature for 4 hours did not differ significantly from values at 1 hour. Results differed significantly between refrigerated and frozen samples stored for 48 hours. CONCLUSIONS AND CLINICAL RELEVANCE Short-term storage conditions influenced results for some biochemical analytes. These effects should be considered when performing biochemical analyses of plasma samples obtained from red-eared sliders.

OBJECTIVE To identify clinical or clinicopathologic variables that can be used to predict a positive PCR assay result for Anaplasma phagocytophilum infection in equids. ANIMALS 162 equids. PROCEDURES Medical records were reviewed to identify equids that underwent testing for evidence of A phagocytophilum infection by PCR assay between June 1, 2007, and December 31, 2015. For each equid that tested positive (case equid), 2 time-matched equids that tested negative for the organism (control equids) were identified. Data collected included age, sex, breed, geographic location (residence at the time of testing), physical examination findings, and CBC and plasma biochemical analysis results. Potential predictor variables were analyzed by stepwise logistic regression followed by classification and regression tree analysis. Generalized additive models were used to evaluate identified predictors of a positive test result for A phagocytophilum. RESULTS Total lymphocyte count, plasma total bilirubin concentration, plasma sodium concentration, and geographic latitude were linear predictors of a positive PCR assay result for A phagocytophilum. Plasma creatine kinase activity was a nonlinear predictor of a positive result. CONCLUSIONS AND CLINICAL RELEVANCE Assessment of predictors identified in this study may help veterinarians identify equids that could benefit from early treatment for anaplasmosis while definitive test results are pending. This information may also help to prevent unnecessary administration of oxytetracycline to equids that are unlikely to test positive for the disease.

Sulfur-induced polioencephalomalacia (PEM) is an important disease affecting cattle in certain geographical regions. However, the pathogenesis of brain damage is not completely understood. We previously observed that excess dietary sulfur may influence thiamine status and altered thiamine metabolism may be involved in the pathogenesis of sulfur-induced PEM in cattle. In this study, we evaluated the activities of thiamine-dependent enzymes [α-ketogluterate dehydrogenase (α-KGDH) and pyruvate dehydrogenase (PDH)] and cytochrome c oxidase (COX) in the cerebral cortex of sulfur-induced PEM-affected cattle (n = 9) and clinically normal cattle (n = 8, each group) exposed to low or high dietary sulfur [LS = 0.30% versus HS = 0.67% sulfur on a dry matter (DM) basis]. Enzyme activities in PEM brains were measured from the brain tissue regions and examined using ultraviolent (UV) light illumination to show fluorescence or non-fluorescence regions. No gross changes under regular or UV light, or histopathological changes indicative of PEM were detected in the brains of cattle exposed to LS or HS diets. The PDH, α-KGDH, and COX activities did not differ between LS and HS brains, but all enzymes showed significantly lower (P < 0.05) activities in UV-positive region of PEM brains compared with LS and HS brains. The UV-negative regions of PEM brain had similar PDH activities to LS and HS brains, but the activities of α-KGDH and COX were significantly lower than in LS and HS brains. The results of this study suggest that reduced enzyme activities of brain PHD, α-KGDH, and COX are associated with the pathogenesis of sulfur-induced PEM.

OBJECTIVE To assess the discriminatory value for corticosteroid-induced alkaline phosphatase (CiALP) activity and other variables that can be measured routinely on a CBC and biochemical analysis for the diagnosis of hypoadrenocorticism in dogs. SAMPLE Medical records of 57 dogs with confirmed hypoadrenocorticism and 57 control dogs in which hypoadrenocorticism was suspected but ruled out. PROCEDURES A retrospective case-control study was conducted. Dogs were included if a CBC and complete biochemical analysis had been performed. Dogs with iatrogenic hypoadrenocorticism and dogs treated previously with glucocorticoids were excluded. Cortisol concentration for dogs with hypoadrenocorticism was ≤ 2 μg/dL both before and after ACTH administration. Cortisol concentration for control dogs was > 4 μg/dL before or after ACTH administration. RESULTS Area under the receiver operating characteristic (ROC) curve for CiALP activity was low (0.646; 95% confidence interval, 0.494 to 0.798). Area under the ROC curve for a model that combined the CiALP activity, Na-to-K ratio, eosinophil count, activity of creatine kinase, and concentrations of SUN and albumin was high (0.994; 95% confidence interval, 0.982 to 1.000). Results for this model could be used to correctly classify all dogs, except for 1 dog with hypoadrenocorticism and no electrolyte abnormalities. CONCLUSIONS AND CLINICAL RELEVANCE CiALP activity alone cannot be used as a reliable diagnostic test for hypoadrenocorticism in dogs. Combined results for CiALP activity, Na-to-K ratio, eosinophil count, creatine kinase activity, and concentrations of SUN and albumin provided an excellent means to discriminate between hypoadrenocorticism and diseases that mimic hypoadrenocorticism.