Cloning of a cysteine proteinase gene of Theileria sergenti.

A cDNA encoding cysteine proteinase of Theileria sergenti was isolated from a piroplasm cDNA library and its nucleotide sequence was determined. The gene encodes a polypeptide of 402 amino acids with predicted molecular mass of 46.4 kDa. Analysis of the predicted amino acid sequence revealed a number of features common to known cysteine proteinases. Southern blot analysis showed that the cysteine proteinase gene was likely to be a single copy per genome.     

Purification and characterization of carbon monoxide dehydrogenase from the aerobic hyperthermophilic archaeon <Emphasis Type="Italic">Aeropyrum pernix</Emphasis>

The aerobic hyperthermophilic archaeon Aeropyrum pernix expresses carbon monoxide (CO) oxidation activity under heterotrophic growth conditions. Using activity stain gel analysis, CO oxidation activity was detected in a protein with a molecular mass of 210 kDa. The 210 kDa CODH protein was purified to homogeneity from A. pernix. Aeropyrum Mo-CODH catalyzed the oxidation of CO with a specific activity of 2.1 μmol CO min⁻¹ mg⁻¹ at 95°C, pH 8.0 using methyl viologen as the electron acceptor. The CODH protein showed high oxygen and thermo stability. The protein contains three subunits: L (86.6 kDa), M (34.5 kDa), and S (12.6 kDa), which form the LM₂S complex. The molecular mass of the complex was calculated by gel filtration and found to be 163.7 kDa. N-terminal amino acid sequencing and peptide mass fingerprinting analysis of the subunits indicated that they corresponded to NP_148462.1, NP_148464.2, and NP_148465.1, and their genes annotated the molybdo iron-sulfur flavoprotein carbon monoxide dehydrogenase S, L, and M subunits, respectively. Phylogenetic analysis revealed that CODH belongs to a novel clade of diverse CODHs.     

Age-specific plasma biochemistry reference ranges in <1 year old dogs in Japan

The purpose of this study was to investigate and propose possible reference intervals of plasma biochemical analytes in young dogs (<12 months old) in Japan, using 896 canine plasma samples, collected from an array of veterinary clinics throughout the greater Tokyo metropolis area in Japan. The following biochemical parameters were assessed: albumin (ALB), alanine aminotransferase (ALT), alkaline phosphatase (ALP), amylase, aspartate aminotransferase (AST), blood urea nitrogen (BUN), creatinine (CRE), glucose, lipase, total cholesterol (T-Cho), and total protein (TP) were evaluated. Multivariate linear regression analysis indicated that partitioning according to age or gender may be necessary for some plasma analytes. Age appeared to significantly affect ALB, ALT, ALP, BUN, Glucose, Lipase, and Total Protein (P=?<0.001, <0.001, <0.001, 0.013, <0.001, 0.025, and <0.001, respectively). On the other hand, gender significantly influenced ALP, Amylase, Lipase, and T-Cho levels (P=0.017, <0.001, <0.001, and <0.001, respectively) whereas it may be borderline significant with ALT (P=0.072).     

Changes in activities of enzymes related to malate-aspartate shuttle in leukocytes from dogs given a herb supplement.

Changes in activities of enzymes related to the malate-aspartate shuttle were measured in leukocytes (WBC) from dogs given food supplemented with 2 mg/kg of herb powder, Echevaria glauca, every day for 4 weeks. There were no significant differences in plasma concentrations of glucose, immunoreactive insulin, free fatty acids and triglyceride between dogs given food with or without the herb supplementation. Activities of malate dehydrogenase (MDH) and aspartate aminotransferase (AST) in the malate-aspartate shuttle increased remarkably in mitochondria of WBC from dogs fed the herb supplementation. It is suggested that Echevaria glauca herb supplementation might activate NADH shuttle systems and mitochondrial energy metabolism in dogs.     

Serum glycated albumin: Potential use as an index of glycemic control in diabetic dogs

Measurements of serum fructosamine, glycated hemoglobin, and glycated albumin (GA) complement serum glucose concentration for better management of diabetes mellitus (DM). Especially, the serum fructosamine test has long been used for diagnosing and monitoring the effect of treatment of DM in dogs. However, fructosamine tests are currently not performed in veterinary medicine in Japan. GA and fructoasmine levels have been shown to strongly correlate. However, the clinical implications of using GA remain to be elucidated. Therefore, the purpose of the current study was threefold: 1) Determine whether GA% is altered by acute hyperglycemia in normal dogs, simulating stress induced hyperglycemia; 2) Demonstrate that GA% does not dynamically change with diurnal variation of blood glucose concentration in diabetic dogs; and 3) Investigate whether GA% is capable of providing an index of glycemic control for 1–3 weeks in diabetic dogs as is the case with diabetic human patients. Our study demonstrated that serum GA% remains very stable and unaltered under acute hyperglycemic conditions (intravenous glucose injection) and in spite of diurnal variation of blood glucose concentration. Furthermore, serum GA% can reflect long-term changes (almost 1–3 weeks) in blood glucose concentration and the effect of injected insulin in diabetic dogs.     

Comparison of insulin signaling gene expression in insulin sensitive tissues between cats and dogs

Diabetes mellitus (DM) is a common endocrine disease in cats and dogs with increasing prevalence. Type 1 DM appears to be the most common form of diabetes in dogs whereas Type 2 DM prevails for cats. Since insulin resistance is more frequently encountered in cats than dogs, our laboratory was interested in determining whether differences at the insulin signaling pathway level and differences in glucose and lipid metabolism could be observed between cats and dogs. Insulin resistance has been positively correlated to insulin signaling pathway abnormalities. As such, this study measured insulin receptor substrate-1 (IRS-1), insulin receptor substrate-2 (IRS-2), and phosphatidylinositol 3-kinase (PI3-K) P-85α mRNA expression levels in classical insulin-responsive sensitive tissues (liver, skeletal muscle, and abdominal fat) and peripheral leukocytes between cats and dogs by qRT-PCR. Different tissues were sampled because it is currently unknown where insulin-resistance arises from. In addition, enzymes involved in glucose and lipid metabolism, malate dehydrogenase (MDH), glucose-6-phosphate dehydrogenase (G6PDH) and fatty acid synthase (FAS) were also assessed since glucose and lipid metabolism differs between cats and dogs. Overall, IRS-1, IRS-2, PI3-K, MDH, G6DPH, and FAS mRNA tissue expression profiles demonstrated different levels of expression, in various tissues for both canines and felines, which was expected. No distinct expression pattern emerged; however, differences were noted between canines and felines. In addition, IRS-1, IRS-2, PI3-K, MDH, G6DPH, and FAS mRNA expression was significantly higher in canine versus feline tissues, including peripheral leukocytes. Remarkable differences in insulin signaling gene expression between felines and canines indicate that cats may have an underlying low insulin sensitivity level due to low IRS-1, IRS-2, and PI3-K P-85α mRNA expression levels which would predispose cats to develop insulin resistance. Moreover, differences in glucose and lipid metabolism related gene expression (MDH, G6DPH, and FAS) demonstrate that felines have an overall lower metabolic rate in various tissues which may be attributed to overall lower insulin signaling gene expression and a lack of physical activity as compared to canines. Therefore, a combination of genetic and environmental factors appears to make felines more prone to suffer from insulin resistance and type 2 DM than canines.     

A comparison of the activities of certain enzymes related to energy metabolism in leukocytes in dogs and cats

The activities of Na>⁺,K>⁺-ATPase in plasma membrane, of cytosolic enzymes and of glutamate dehydrogenase (GlGD) in mitochondria were measured in leukocytes (WBC) from dogs and cats to clarify the differences in energy metabolism in these cells. Feline WBC had significantly higher activities of hexokinase (HK), pyruvate kinase (PK) and LDH with pyruvate as substrate than did canine WBC. Canine WBC had significantly higher activities of glucokinase (GK) and GlDH than did feline WBC. Feline WBC had unique characteristics of energy metabolism in that the activities of the cytosolic enzymes under anaerobic conditions were significantly higher than those in canine WBC. It therefore appears that there are distinct differences in glucose metabolism in WBC between dogs and cats. WBC enzyme activities are considered to reflect the metabolic state in the whole body of the animal. It is therefore suggested that changes in the activities of certain glycolytic enzymes in WBC may be useful as a diagnostic indicator in some types of metabolic disease in dogs and cats.