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Effect of pregnancy and stage of lactation on energy processes in isolated blood cells of dairy cows
2017
Dębski, Bogdan | Nowicki, Tadeusz | Zalewski, Wojciech | Bartoszewicz, Agnieszka | Twardoń, Jan
Introduction: The transition period is the most challenging time for dairy cattle, which is characterised not only by negative energy balance but also by fatty tissue mobilisation.Material and Methods: The efficiency of energy pathways, β-oxidation in WBC and glycolysis in RBC (based on deoxyglucose transmembrane transport) were estimated. Insulin in blood plasma was determined using ELISA.Results: After calving and up to one month after delivery, a significant drop in blood plasma level was noticed, simultaneously with a rise in β-oxidation from 18.93 ±3.64 to 30.32 ±5.28 pmol/min/mg protein in WBC. A strong negative correlation between these two indices (r = −0.68) was found. During the period of transition to lactation an increase in glucose cross-membrane transportation from 41.44 ±4.92 to 50.49 ±6.41 μmol/h/g Hb was observed. A strong positive correlation between glucose transportation in RBC and β-oxidation in WBC (r = 0.71) was noticed. These data are in agreement with results of studies on dairy cows using liver slices from dairy cows in late pregnancy and different stages of lactation, in which changes in gene expression were analysed.Conclusion: It seems that measuring fatty acids oxidation and glycolysis using isolated blood cells may be an adequate and relatively simple method for energy state analysis to estimate the state of dairy cow metabolism and animal health.
Afficher plus [+] Moins [-]Preliminary study on gene regulation and its pathways in Chinese Holstein cows with clinical mastitis caused by Staphylococcus aureus
2022
Wang, Wenjia | Li, Rongling | Ye, Tingzhu | Zhang, Xinxin | Chen, Chao | Liang, Ai-xin | Yang, Li-guo
Clinical mastitis (CM) is one of the most common diseases of dairy cows globally, has a complex aetiology and recurs easily. Staphylococcus aureus is a frequently isolated pathogen responsible for bovine mastitis and remains difficult to eradicate. To characterise the transcriptional profiles of dairy cows infected by S. aureus, we performed an RNA-seq analysis of peripheral blood leukocytes in lactating Chinese Holstein dairy cows with CM and did the same with healthy cows’ samples as controls. A total of 4,286 genes were detected in the CM cases infected with S. aureus which were differentially expressed compared to the controls, 3,085 of which were upregulated, the remainder being downregulated. Notably, we observed that some differentially expressed genes (DEGs) had strong protein–protein interaction. Of these, six downregulated DEGs (AKR1C4, PTGS2, HNMT, EPHX2, CMBL, and IDH1) were involved in the metabolic pathway, while eight upregulated DEGs (VWF, GP9, MYLK, GP6, F2RL3, ITGB3, GP5, and PRKG1) were associated with the platelet activation pathway. The transcriptome dataset of CM cases would be a valuable resource for clinical guidance on anti-inflammatory medication and for deeper understanding of the biological processes of CM response to S. aureus infection, and it would enable us to identify specific genes for diagnostic markers and possibly for targeted therapy.
Afficher plus [+] Moins [-]Fasciola hepatica isolates induce different immune responses in unmaturated bovine macrophages
2019
Bąska, Piotr | Zawistowska-Deniziak, Anna | Norbury, Luke James | Wiśniewski, Marcin | Januszkiewicz, Kamil
Introduction: Fasciola hepatica (liver fluke) is a parasite of great socioeconomic importance. A number of fluke isolates have been identified; however, to date the differences between the immunomodulatory properties of different parasite isolates have not been sufficiently investigated. The aim of this study was to explore differences between the immunomodulatory properties of two F. hepatica isolates using unmaturated bovine macrophages. Material and Methods: A cell line of bovine macrophages was stimulated with excretory/secretory products released by adult flukes from either a laboratory (Fh-WeyES) or wild (Fh-WildES) strain and subsequently subjected to microarray and ELISA analyses. Results: Both Fh-WeyES and Fh-WildES dampened the release of interleukin-10 by bovine macrophages, but only Fh-WildES dampened the release of proinflammatory tumour necrosis factor-α. Microarray analysis revealed that Fh-WildES down- and upregulated 90 and 18 genes, respectively, when compared to Fh-WeyES. Conclusion: The results indicated different impacts of the isolates on macrophages. A number of researchers use flukes obtained from local slaughterhouses for experiments. Our findings may explain some discrepancies between published results arising from parasite strain choice. The findings indicate that consideration should be given to the use of different strains, and open new and currently unexplored avenues in parasitology for controlling the parasite.
Afficher plus [+] Moins [-]Cloning and differential expression analyses of Cdc42 from sheep
2018
Yang, Yong-Jie | Liu, Zeng-Shan | Lu, Shi-Ying | Hu, Pan | Li, Chuang | Ahmad, Waqas | Li, Yan-Song | Xu, Yun-Ming | Tang, Feng | Zhou, Yu | Ren, Hong-Lin
Serological diagnosis of brucellosis is still a great challenge due to the infeasibility of discriminating infected animals from vaccinated ones, so it is necessary to search for diagnostic biomarkers for differential diagnosis of brucellosis. Cell division cycle 42 (Cdc42) from sheep (Ovis aries) (OaCdc42) was cloned by rapid amplification of cDNA ends (RACE), and then tissue distribution and differential expression levels of OaCdc42 mRNA between infected and vaccinated sheep were analysed by RT-qPCR. The full-length cDNA of OaCdc42 was 1,609 bp containing an open reading frame (ORF) of 576 bp. OaCdc42 mRNAs were detected in the heart, liver, spleen, lung, kidneys, rumen, small intestine, skeletal muscles, and buffy coat, and the highest expression was detected in the small intestine. Compared to the control, the levels of OaCdc42 mRNA from sheep infected with Brucella melitensis or sheep vaccinated with Brucella suis S2 was significantly different (P < 0.01) after 40 and 30 days post-inoculation, respectively. However, the expression of OaCdc42 mRNA was significantly different between vaccinated and infected sheep (P < 0.05 or P < 0.01) on days: 14, 30, and 60 post-inoculation, whereas no significant difference (P > 0.05) was noted 40 days post-inoculation. Moreover, the expression of OaCdc42 from both infected and vaccinated sheep showed irregularity. OaCdc42 is not a good potential diagnostic biomarker for differential diagnosis of brucellosis in sheep.
Afficher plus [+] Moins [-]Investigation of effects of omeprazole on the fecal and gastric microbiota of healthy adult horses
2019
Tyma, Jesse F. | Epstein, Kira L. | Whitefield-Cargile, Canaan M. | Cohen, Noah D. | Giguère, S. (Steeve)
OBJECTIVE To determine the effects of oral omeprazole administration on the fecal and gastric microbiota of healthy adult horses. ANIMALS 12 healthy adult research horses. PROCEDURES Horses were randomly assigned to receive omeprazole paste (4 mg/kg, PO, q 24 h) or a sham (control) treatment (tap water [20 mL, PO, q 24 h]) for 28 days. Fecal and gastric fluid samples were collected prior to the first treatment (day 0), and on days 7, 28, 35, and 56. Sample DNA was extracted, and bacterial 16S rRNA gene sequences were amplified and sequenced to characterize α and β diversity and differential expression of the fecal and gastric microbiota. Data were analyzed by visual examination and by statistical methods. RESULTS Composition and diversity of the fecal microbiota did not differ significantly between treatment groups or over time. Substantial variation in gastric fluid results within groups and over time precluded meaningful interpretation of the microbiota in those samples. CONCLUSIONS AND CLINICAL RELEVANCE Results supported that omeprazole administration had no effect on fecal microbiota composition and diversity in this group of healthy adult horses. Small sample size limited power to detect a difference if one existed; however, qualitative graphic examination supported that any difference would likely have been small and of limited clinical importance. Adequate data to evaluate potential effects on the gastric microbiota were not obtained. Investigations are needed to determine the effects of omeprazole in horses with systemic disease or horses receiving other medical treatments.
Afficher plus [+] Moins [-]Effect of firocoxib on cyclooxygenase 2, microsomal prostaglandin E2 synthase 1, and cytosolic phospholipase A2 gene expression in equine mononuclear cells
2015
Barton, Michelle H. | Darden, Joshua E. | Clifton, Sarah | Vandenplas, Michel
OBJECTIVE To validate primer sets for use in reverse transcription quantitative PCR assays to measure gene expression of cytosolic phospholipase A2 (cPLA2) and microsomal prostaglandin E2 synthase 1 (mPGES1) in equine mononuclear cells and determine the effects of firocoxib, a selective cyclooxygenase 2 (COX-2) inhibitor, on COX-2, cPLA2, and mPGES1 gene expression following incubation of mononuclear cells with lipopolysaccharide (LPS). ANIMALS 8 healthy adult horses. PROCEDURES Peripheral blood mononuclear cells were isolated by density gradient centrifugation and incubated at 37°C with medium alone, firocoxib (100 ng/mL), LPS (1 ng/mL or 1 μg/mL), or combinations of firocoxib and both LPS concentrations. After 4 hours, supernatants were collected and tested for prostaglandin E2 (PGE2) concentration with an enzyme inhibition assay, and gene expression in cell lysates was measured with PCR assays. RESULTS Primer pairs for cPLA2 and mPGES1 yielded single products on dissociation curve analyses, with mean assay efficiencies of 102% and 100%, respectively. Incubation with firocoxib and LPS significantly decreased PGE2 supernatant concentrations and significantly reduced COX-2 and mPGES1 gene expression, compared with values following incubation with LPS alone. CONCLUSIONS AND CLINICAL RELEVANCE Primer sets for mPGES1 and cPLA2 gene expression in equine mononuclear cells were successfully validated. Firocoxib significantly decreased LPS-induced COX-2 and mPGES1 expression, suggesting that it may be useful in the control of diseases in which expression of these genes is upregulated.
Afficher plus [+] Moins [-]Identification of potential biomarkers of P-glycoprotein substrate neurotoxicity in transgenic mice expressing the mutated canine ABCB1 gene
2014
Zhu, Min | Ming, Yi | Swaim, Heidi | Swain, Marla D. | Myers, Michael J. | Deaver, Christine | Wu, Xiaolin | Jones, Yolanda L. | Yancy, Haile F.
Objective—To identify biomarkers of P-glycoprotein (P-gp) substrate neurotoxicity in transgenic mice expressing the mutant canine ABCB1 gene (ABCB1-1Δ). Animals—8 ABCB1 knock-in and knock-out transgenic mice expressing the ABCB1-1Δ gene and 8 control mice expressing the wild-type canine ABCB1 gene (ABCB1-WT). Procedures—Groups including 2 ABCB1-1Δ mutant mice and 2 ABCB1-WT mice were administered the P-gp substrates ivermectin (10 mg/kg, SC), doramectin (10 mg/kg, SC), moxidectin (10 mg/kg, PO), or digoxin (1.53 mg/kg, SC). A toxicogenomic approach based on DNA microarrays was used to examine whole-genome expression changes in mice administered P-gp substrates. Results—Compared with control ABCB1-WT mice, ABCB1-1Δ mutant mice developed neurotoxic signs including ataxia, lethargy, and tremors similar to those reported for dogs with the ABCB1-1Δ mutation. Microarray analysis revealed that gene expression was altered in ABCB1-1Δ mutant mice, compared with findings for ABCB1-WT mice, following administration of the same P-gp substrates. Gene pathway analysis revealed that genes with a ≥ 2-fold gene expression change were associated with behavior and nervous system development and function. Moreover, 34 genes were altered in the ABCB1-1Δ mutant mice in all 4 drug treatment groups. These genes were also associated with behavior, which was identified as the top-ranked gene network. Conclusions and Clinical Relevance—These study data have facilitated understanding of the molecular mechanisms of neurotoxicosis in ABCB1-1Δ mutant mice following exposure to various P-gp substrates. Some genes appear to be potential biomarkers of P-gp substrate neurotoxicity that might be used to predict the safety of those drugs in dogs with the ABCB1-1Δ mutation.
Afficher plus [+] Moins [-]Differences in virulence gene expression between atypical enteropathogenic Escherichia coli strains isolated from diarrheic and healthy ruminants
2013
Horcajo, Pilar | Domínguez-Bernal, Gustavo | Carrion, Javier | Fuente, Ricardo de la | Ruiz-Santa-Quiteria, José A. | Orden, José A.
Differences in the pathogenicity of atypical enteropathogenic Escherichia coli (EPEC) strains may be due, at least partially, to different expression patterns of some virulence genes. To investigate this hypothesis, the virulence gene expression patterns of 6 atypical EPEC strains isolated from healthy and diarrheic ruminants were compared using quantitative real-time reverse transcription polymerase chain reaction after growing the bacteria in culture medium alone or after binding it to HeLa epithelial cells. Some virulence genes in strains from diarrheic animals were upregulated relative to their expression in strains from healthy animals. When bacteria were cultured in the presence of HeLa cells, the ehxA and efa1/lifA genes, previously associated with the production of diarrhea, were expressed at higher levels in strains from diarrheic animals than in strains from healthy animals. Thus, the expression levels of some virulence genes may help determine which atypical EPEC strains cause diarrhea in ruminants.
Afficher plus [+] Moins [-]Activity of feline interferon-omega after ocular or oral administration in cats as indicated by Mx protein expression in conjunctival and white blood cells
2006
Bracklein, T. | Theise, S. | Metzler, A. | Spiess, B.M. | Richter, M.
Objective-To assess the biological response to recombinant feline interferon-omega (rFeIFN-omega) following ocular or oral administration in cats via estimation of Mx protein expression in conjunctival cells (CCs) and WBCs. Animals-10 specific pathogen-free cats. Procedures-In multiple single-dose drug experiments, each cat received various concentrations of rFeIFN-omega administered topically into both eyes (50 to 10,000 U/eye) and orally (200 to 20,000 units). The same cats received saline (0.9% NaCl) solution topically and orally as control treatments. The CCs and WBCs were collected prior to treatment (day 0), on day 1, and every third or seventh day thereafter until samples yielded negative results for Mx protein. Samples were examined for Mx protein expression via immunohistochemistry and immunoblotting procedures involving murine anti-Mx protein monoclonal antibody M143. Results-After topical application of 10,000 U of rFeIFN-omega/eye, CCs stained for Mx protein for a minimum of 7 days, whereas WBCs were positive for Mx protein for a minimum of 31 days. After topical application of lower concentrations, CCs did not express Mx protein, in contrast to WBCs, which stained for Mx protein at 1,000 units for at least 1 day. Following oral administration, Mx protein was expressed in WBCs at rFeIFN-omega concentrations as low as 200 units, whereas CCs did not stain for Mx protein at any concentration. Conclusions and Clinical Relevance-Results indicate that Mx protein expression (a marker of the biological response to rFeIFN-omega) in CCs and WBCs of rFeIFN-omega-treated cats depends on the dose of rFeIFN-omega, site of administration, and cell type.
Afficher plus [+] Moins [-]Characterization of canine mitochondrial protein expression in natural and induced forms of idiopathic dilated cardiomyopathy
2006
Lopes, R. | Solter, P.F. | Sisson, D.D. | Oyama, M.A. | Prosek, R.
Objective-To map canine mitochondrial proteins and identify qualitative and quantitative differences in heart mitochondrial protein expression between healthy dogs and dogs with naturally occurring and induced dilated cardiomyopathy (DCM). Sample Population-Left ventricle samples were obtained from 7 healthy dogs, 7 Doberman Pinschers with naturally occurring DCM, and 7 dogs with induced DCM. Procedures-Fresh and frozen mitochondrial fractions were isolated from the left ventricular free wall and analyzed by 2-dimensional electrophoresis. Protein spots that increased or decreased in density by greater than or equal to 2-fold between groups were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or quadrupole selecting, quadrupole collision cell, time-of-flight mass spectrometry. Results-Within narrow pH gradients of control canine heart mitochondrial samples, a total of 1,528 protein spots were revealed. Forty subunits of heart mitochondrial proteins that differ significantly from control tissues were altered in tissue specimens from dogs with naturally occurring and induced forms of DCM. The most affected heart mitochondrial proteins in both groups were those of oxidative phosphorylation (55%). Upregulation of manganese superoxide dismutase was suggestive of heart oxidative injury in tissue specimens from dogs with both forms of DCM. Evidence of apoptosis was associated with overexpression of the heart mitochondrial voltage-dependent anion channel-2 protein and endonuclease G in tissue specimens from dogs with induced DCM. Conclusions and Clinical Relevance-Alterations of heart mitochondrial proteins related to oxidative phosphorylation dysfunction were more prevalent in tissue specimens from dogs with induced or naturally occurring DCM, compared with those of control dogs.
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