Activity Of Peripheral Leukocytes Research Articles

Effects of stimulation of glutamate receptors in medial septum on some immune responses in rats

The immunomodulatory role of medial septum (MS) has been explored so far only in MS lesioned rats. But in MS lesioned rats, all the nerve cells and fibres of the lesioned area are damaged and the specific role of the neural circuits of MS on immunomodulation cannot be assessed from the lesion of MS. Considering the presence of a large number of glutamate receptors in MS, the specific role of glutamate receptors stimulation on some immune responses has been investigated in the present study. Hyperreactive behaviour, TC and DC of WBC, phagocytic activity of peripheral leukocytes, adhesibility and cytotoxicity of splenic mononuclear cells (MNC), delayed type of hypersensitivity (DTH) responses and the serum corticosterone (CORT) were measured after microinfusion of glutamate into MS of rats. To ascertain the specific role of those glutamate receptors, the parameters were also measured after microinfusion of glutamate receptor blocker 6, 7-dinitroquinoxaline-2, 3-dione (DNQX). The hyperreactive behaviour, TC and DC of WBC remained unaltered after stimulation or blocking of glutamate receptors. The phagocytic activity, adhesibility and cytotoxicity of splenic MNC, and DTH responses were increased after infusion of 0.25 and 0.5µM glutamate. But after infusion of higher dose of glutamate (1µM), the phagocytic activity and the adhesibility of splenic MNC were decreased and other parameters remained unaltered in that condition. After infusion of 4 and 8mM DNQX all the observed immunological parameters were decreased. The CORT concentration was decreased after infusion of 0.25 and 0.5µM of glutamate but it was increased after infusion of 1µM glutamate or 4 and 8mM DNQX. Results indicate that the medial septal glutamate receptors play an important role in the modulation of some immune responses.

Cocaine-Induced Endothelial Dysfunction: Role of RhoA/Rho Kinase Pathway Activation.

AbstractAbstract 2177 Background.Cocaine abuse is associated with an increased risk of cardiac and cerebrovascular events, such as myocardial infarction, sudden cardiac death, and ischemic stroke. The underlying mechanisms leading to these complications are not fully understood although intravascular thrombus formation and accelerated atherosclerosis are prominent findings. We have recently demonstrated that chronic cocaine use is associated with endothelial dysfunction (Sáez et al. Thromb Res 2011; 128: 18), a key event in the onset and progression of atherosclerosis. There is growing evidence that the RhoA/Rho kinase (ROCK) pathway has an important pathophysiological role in vascular endothelial dysfunction. Accordingly, we hypothesized that cocaine use induces activation of RhoA/ROCK pathway. Objectives.The main aim of this work was to investigate the activation of RhoA/ROCK pathway through ex vivo, in vivo and in vitro studies. Methods.Ex vivo studies. We studied 13 cocaine dependent individuals (aged 19–52 years mean age 37 years) who met DSM-IV criteria for cocaine dependence, seeking treatment for cocaine abuse and age, sex-matched healthy controls (aged 20–49 years, mean age 35 years). Samples were obtained at admission, within 72 hours of drug exposure. Endothelial cell damage was determined by enumerating circulating endothelial cells (CECs). Rho-kinase activity was assessed by the levels of phosphorylated to total myosin light chain phosphatase 1 (MYPT1-P/T) in circulating leukocytes. In vivo studies. Adult male Sprague-Dawley rats were randomly assigned to receive either cocaine (30mg/kg, provided by NIDA, USA) or saline intraperitoneally once daily for 21 days. The levels of aortic phosphorylated MYPT1 (phospho-MYPT1) were assessed by western blot in aorta extracts. In vitro experiments. Human umbilical vein endothelial cells (HUVECs) were cultured under standard conditions and supplemented for 5 hours with plasma from chronic cocaine users, normal plasma, cocaine (10μM) or vehicle. After media removal, HUVECs were either lysed for determination of ROCK activity or co-cultured with resting platelets and immunostained for von Willebrand factor (FVW). Platelet adhesion was evaluated by immunofluorescence microsocopy. Experiments were conducted in the presence or absence of ROCK inhibitors, Y-27632 (10 μM) or atorvastatin (10μM). Results.Cocaine users showed significantly elevated number of CECs compared to the controls (65 ± 6.6 vs 14 ± 3.4 cells/mL, p: 0.0002). In the control subjects, leukocyte mean MYPT1-P/T ratio was 2.2 ± 0.8 whereas in cocaine addicts were significantly increased (9.8 ± 2.8; p 0.015). ROCK activity was higher by 100% (p: 0.019) in the aortic wall of the cocaine-treated rats compared to sham animals. HUVECs supplemented with plasma from cocaine users showed an increase in ROCK activity by 25% (p: 0.039), released significantly higher amount of FVW (p<0.05) and adhered a larger number of platelets (22.6±5 vs 7.9±3 platelets/cell, respectively; p: 0.006) compared with control plasma. Cocaine exposure induced a dramatically higher number of platelets adhered to HUVEC than in vehicle-treated cells (220±73 vs 10.2±1.1 platelets/cell, respectively; p>0.001).ROCK inhibitors, atorvastatin and Y-27632 reduced the release of FVW by HUVECs exposed to plasma from cocaine users by 65% (p: 0.004) and strongly inhibited platelet adhesion (by 75% in plasma-treated cells and by 90% in HUVECs exposed to cocaine, p:< 0.006). Conclusions.We found an increase in Rho kinase activity in peripheral leukocytes of cocaine abusers, in the vessel wall of rats exposed to cocaine and a marked positive effect of ROCK inhibitors on the cellular injury induced by cocaine or plasma from cocaine consumers on endothelial cells. Collectively, these data suggest that activation of RhoA/ROCK pathway plays a key role in cocaine-induced endothelial dysfunction. Inhibition of ROCK may provide therapeutic benefits in a comprehensive treatment for cocaine addiction. Disclosures:No relevant conflicts of interest to declare.

Effects of Chinese herbal medicine Shoushen Granule on telomere length and telomerase activity of peripheral white blood cells and vascular cells in rats with atherosclerosis

To observe the effects of Shoushen Granule, a compound traditional Chinese herbal medicine, on telomere length and telomerase activity in peripheral leukocytes and vascular cells, artery wall lesions and blood lipid in a Sprague-Dawley (SD) rat model of atherosclerosis. Forty SD rats were randomly divided into normal control group, model group, Shoushen Granule group and Western medicine group with 10 in each group. The rat model of atherosclerosis was established by high-fat diet and vitamin D3 loading. The model group was given gastric perfusion of double distilled water; The Shoushen Granule group and the Western medicine group were respectively given gastric perfusion of Shoushen Granule and pravastatin. After 12 weeks, pathological changes of abdominal aorta were determined by hematoxylin and eosin staining. Biochemical colorimetric method was used to detect the contents of total cholesterol (TC), triacylglycerol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol (LDL-C) in serum of the rats. Telomere length and telomerase activity in peripheral leukocytes and vascular cells of the rats were tested by quantitative real-time polymerase chain reaction method. When compared with the model group, atherosclerosis lesions of the arterial wall were significantly improved in the Shoushen Granule group. In addition, both TC and LDL-C levels in the Shoushen Granule group were decreased significantly compared with the model group (P<0.01). Besides, not only telomerase activity but also telomere length in peripheral leukocytes (P<0.01) and vascular cells (P<0.05) were increased significantly as compared to those in the model group. However, there was no significant difference between the Shoushen Granule group and the normal control group (P>0.05). Shoushen Granule improves the atherosclerosis lesions in rats, and the mechanism may be related to regulating telomere length and telomerase activity.

Interleukin-1&amp;bgr; Increases Release of Endothelin-1 and Tumor Necrosis Factor as Well as Reactive Oxygen Species by Peripheral Leukocytes During Experimental Subarachnoid Hemorrhage

In the subarachnoid hemorrhage (SAH) blood mixes with cerebrospinal fluid, what starts immunoinflammatory processes - increased synthesis of proinflammatory cytokines, and formation of reactive oxygen species (ROS), resulting in pre-activation of different populations of peripheral leukocytes. Migration of leukocytes to the brain parenchyma through broken blood brain barrier may produce extra brain tissue injury besides of that resulting from SAH. We examined in adult rats the effect of interleukin-1β (IL-1β) neutralization on secretion of cytokines as well as production of ROS in the course of SAH. SAH was produced by injection of 150 μL of autologous arterial blood into cisterna magna. In 50% of animals, IL-1beta activity was inhibited by intracerebroventricular administration of anti-rat IL-1β antibodies. Ninety minutes or 24 hrs following surgery, blood samples were drawn from the extraorbital plexus and centrifuged to obtain two leukocyte subpopulations - polymorphonuclear (PMN) and mononuclear (MN). The chemiluminescence, a hallmark of ROS synthesis, was measured in PMNs. In supernatants from MNs cultures, concentrations endothelin-1 (ET-1), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were assessed. SAH caused the increase ofn PMNs chemiluminescence as well as the increase of production of ET-1 and TNF-α by MNs but had no influence on IL-6 concentration. Neutralization of IL-1β resulted in significant decrease of chemiluminescence as well as concentration of both ET-1 and TNF-α, while IL-6 concentration was increased. These revealed an important role of IL-1β in the activation of peripheral leukocytes in the course of subarachnoid hemorrhage.

Mineralocorticoid Receptor Blocker Eplerenone Improves Endothelial Function and Inhibits Rho-Associated Kinase Activity in Patients With Hypertension

Hypertension is associated with endothelial dysfunction and activated Rho-associated kinases (ROCKs). The purpose of this study was to evaluate the effects of the selective mineralocorticoid receptor blocker, eplerenone, on endothelial function and ROCK activity in patients with hypertension. The study was carried out over 48 weeks in 60 untreated patients with hypertension who were randomly assigned to eplerenone, nifedipine, and losartan groups. We evaluated the effects of each treatment on flow-mediated vasodilation (FMD) and ROCK activity in peripheral leukocytes. Eplerenone increased FMD and decreased leukocyte ROCK activity. Nifedipine decreased ROCK activity but did not alter FMD. Losartan increased FMD but did not alter ROCK activity. Hypotensive effects were similar in the three groups, as was nitroglycerin-induced vasodilation during the follow-up period. There were no significant differences between the groups with respect to other parameters. The study results show that eplerenone improves endothelial function and inhibits ROCK activity in patients with essential hypertension.

Glucocerebrosidase gene variants in parkinsonian patients with Machado Joseph/spinocerebellar ataxia 3

Machado-Joseph disease/spinocerebellar ataxia type 3 (MJD/SCA3) may rarely presents a parkinsonian phenotype. Considering that mutations in the glucocerebrosidase (GBA) gene have been associated with Parkinson disease, we investigated whether these would be more prevalent in MJD/SCA3 patients with parkinsonian manifestations than in those without them. MethodsMJD/SCA3 patients with parkinsonian features were identified and compared to relatives and to a MJD/SCA3 control group with no such features. The GBA gene was sequenced and, in a subset of patients and in normal volunteers, GBA enzyme activity was measured. ResultsWe have identified nine index MJD/SCA3 patients with parkinsonian manifestations. Overall, GBA sequence variations were found in 3/9 MJD/SCA3 index cases with parkinsonian manifestations (33%) and in 0/40 MJD/SCA3 controls without parkinsonism (p=0.03, Fisher exact test). The GBA sequence variations found were p.K(-27)R, p.E326K, and p.T369M. The latter two sequence variations were also found in two symptomatic relatives with no parkinsonian manifestations. A MJD/SCA3 relative belonging to the first positive pedigree and carrier of the p.K(-27)R mutation also presented parkinsonian manifestations. GBA activity in MJD/SCA3 patients was similar to those found in the normal control group. ConclusionSequence variations at the GBA gene may play a role as a minor, modifying gene of MJD/SCA3 phenotype. This hypothetical role was not related to changes in GBA activity in peripheral leukocytes.

Rho-Associated Kinase Activity, Endothelial Function, and Cardiovascular Risk Factors

Cardiovascular diseases are associated with chronic activation of Rho-associated kinases (ROCKs) and endothelial dysfunction. Both increased ROCK activity and endothelial dysfunction are thought to be closely associated with conventional cardiovascular risk factors. The purpose of this study was to determine the relationships between ROCK activity, endothelial function, and cardiovascular risk factors. We evaluated ROCK activity in peripheral leukocytes by Western blot analysis and flow-mediated vasodilation by ultrasonography in 242 men who had no cardiovascular or cerebrovascular diseases (mean age, 40±10 years; range, 20 to 73 years). ROCK activity was defined as the ratio of phospho myosin-binding subunit on myosin light chain phosphatase to total myosin-binding subunit. Univariate regression analysis revealed that leukocyte ROCK activity significantly correlated with body mass index (r=0.29, P=0.003); systolic blood pressure (r=0.25, P=0.01); low-density lipoprotein cholesterol level (r=0.21, P=0.04); and Framingham risk factor score, a cumulative cardiovascular risk index for heart attack (r=0.31, P<0.001), and that flow-mediated vasodilation significantly correlated with age (r=-0.23, P=0.02), body mass index (r=0.19, P=0.05), systolic blood pressure (r=-0.22, P=0.03), total cholesterol level (r=-0.21, P=0.04), low-density lipoprotein cholesterol level (r=-0.22, P=0.04), glucose level (r=-0.20, P=0.04), and Framingham risk factor score (r=-0.37, P<0.001). There was a significant correlation between leukocyte ROCK activity and flow-mediated vasodilation (r=-0.41, P<0.001). Multivariate analysis revealed that flow-mediated vasodilation was an independent predictor of leukocyte ROCK activity. These findings suggest that cumulative cardiovascular risk may enhance ROCK activity and endothelial dysfunction, leading to progression of cardiovascular diseases and outcomes.

Analysis of the Mitochondrial Complex I-V Enzyme Activities of Peripheral Leukocytes in Oxidative Phosphorylation Disorders

Mitochondrial oxidative phosphorylation defects are a common cause of mitochondrial diseases, which are characterized by multiorgan involvement and clinically heterogeneous manifestations. Diagnosis is difficult because of the lack of clinically feasible methods. In this study, mitochondrial complex I-V enzyme activity was measured in 64 patients with suspected mitochondrial disease and 200 healthy controls. Spectrophotometric assay was used for the analysis of mitochondrial complex I-V enzyme activity in peripheral leukocytes. Diagnosis was based on clinical presentation, magnetic resonance imaging (MRI), muscle pathology, and point mutation screening in mitochondrial DNA. The differential diagnosis of aminoacidopathies, organic acidurias, and fatty acid β-oxidation defects was made. Thirty-five patients (54.7%) were diagnosed with Leigh syndrome based on characteristic brain MRI. Complex enzyme activity in controls was found to be stable. A deficiency in the oxidative phosphorylation was found in 29 patients (45.3%). Twenty (31.2%) patients had isolated complex defects, complex I deficiency (n = 2, 3.1%), complex II deficiency (n = 3, 4.7%), complex III deficiency (n = 5, 7.8%), complex IV deficiency (n = 5, 7.8%), and complex V deficiency (n = 5, 7.8%). Nine patients were found to have combined deficiencies, 3 (4.7%) had combined deficiencies of complex I and IV, 2 (3.1%) had combined deficiencies of complex III and V, and 2 (3.1%) had a combined deficiency of complex I and V. In conclusion, the peripheral leukocyte oxidative phosphorylation enzyme activity assay was found to be a reliable method for the diagnosis of mitochondrial diseases.

Therapy with recombinant T-cell receptor ligand reduces infarct size and infiltrating inflammatory cells in brain after middle cerebral artery occlusion in mice

Stroke induces a biphasic effect on the peripheral immune response that involves early activation of peripheral leukocytes followed by severe immunosuppression and atrophy of the spleen. Peripheral immune cells, including T lymphocytes, migrate to the brain and exacerbate the developing infarct. Recombinant T-cell receptor (TCR) Ligand (RTL)551 is designed as a partial TCR agonist for myelin oligodendrocyte glycoprotein (MOG)-reactive T cells and has demonstrated the capacity to limit infarct volume and inflammation in brain when administered to mice undergoing middle cerebral artery occlusion (MCAO). The goal of this study was to determine if RTL551 could retain protection when given within the therapeutically relevant 4 h time window currently in clinical practice for stroke patients. RTL551 was administered subcutaneously 4 h after MCAO, with repeated doses every 24 h until the time of euthanasia. Cell numbers were assessed in the brain, blood, spleen and lymph nodes and infarct size was measured after 24 and 96 h reperfusion. RTL551 reduced infarct size in both cortex and striatum at 24 h and in cortex at 96 h after MCAO and inhibited the accumulation of inflammatory cells in brain at both time points. At 24 h post-MCAO, RTL551 reduced the frequency of the activation marker, CD44, on T-cells in blood and in the ischemic hemisphere. Moreover, RTL551 reduced expression of the chemokine receptors, CCR5 in lymph nodes and spleen, and CCR7 in the blood and lymph nodes. These data demonstrate effective treatment of experimental stroke with RTL551 within a therapeutically relevant 4 h time window through immune regulation of myelin-reactive inflammatory T-cells.

Calcium channel blocker and Rho-associated kinase activity in patients with hypertension

Rho-associated kinases (ROCKs) play an important role in Ca sensitization and vascular resistance. Activation of ROCKs is associated with hypertension. The purpose of this study was to evaluate the effect of the calcium channel blocker amlodipine on ROCKs activity in patients with hypertension. We evaluated ROCK activity in peripheral leukocytes by Western blot analysis in 651 patients with hypertension treated with antihypertensive agents, 28 untreated hypertensive patients and 28 healthy individuals, and the effects of treatment with amlodipine or losartan for 12 weeks on ROCK activity in 28 untreated hypertensive patients who were randomly divided into an amlodipine group (n = 14) and a losartan group (n = 14). ROCK activity was defined as the ratio of phospho myosin-binding subunit (MBS) on myosin light-chain phosphatase to total MBS. Leukocyte ROCK activity was greater in untreated patients with essential hypertension than in the healthy individuals (0.84 ± 0.24 vs. 0.61 ± 0.18, P = 0.03). In 651 patients with hypertension treated with antihypertensive agents, ROCK activity was significantly lower in the calcium channel blocker-treated group than in the groups treated with renin-angiotensin system inhibitors, diuretics, and β-blockers (0.70 ± 0.24 vs. 0.85 ± 0.29, 0.83 ± 0.24, and 0.86 ± 0.31, P < 0.05, respectively). ROCK activity after 4 and 12 weeks of treatment was significantly decreased in the amlodipine group (0 weeks: 0.85 ± 0.25, 4 weeks: 0.66 ± 0.16, 12 weeks: 0.64 ± 0.15, P < 0.05, respectively) but not in the losartan group, whereas the antihypertensive effects were similar in the two groups. These findings suggest that calcium channel blocker amlodipine inhibits ROCK activity in patients with hypertension.

Increased leukocyte rho kinase (ROCK) activity and endothelial dysfunction in cigarette smokers

Rho-associated kinases (ROCKs) have been shown to be involved in the pathogenesis of atherosclerosis. Although smoking is associated with endothelial dysfunction and ROCK inhibitors improve endothelial function in smokers, it is not known whether ROCK activity is increased in smokers and whether this correlates with endothelial dysfunction. The purpose of this study was to evaluate the relationship between ROCK activity and endothelial function in smokers. We evaluated flow-mediated vasodilatation (FMD) using ultrasonography and ROCK activity in peripheral leukocytes using western blot analysis in 14 male smokers (28.1+/-3.9 years) and 15 healthy male non-smokers (28.3+/-3.6 years). ROCK activity was defined as the ratio of phospho-myosin-binding subunit (MBS) on myosin light-chain phosphatase to total MBS. FMD was significantly less in smokers than in non-smokers (4.7+/-3.1 vs. 9.0+/-3.8%, P=0.005). Nitroglycerine-induced vasodilation was similar in the two groups. ROCK activity was greater in smokers than in non-smokers (0.78+/-0.27 vs. 0.54+/-018, P=0.012). The expression of total MBS, ROCK1 and ROCK2 were similar in the two groups. ROCK activity correlated with systolic blood pressure (r=0.42, P=0.039). Multiple regression analysis revealed that smoking is an independent predictor of ROCK activity. There was a significant correlation between FMD and ROCK activity (r=-0.42, P=0.035). No other variable was correlated with FMD. These findings suggest that ROCK activity is enhanced by smoking and is a predictor of endothelial function.

Interleukin-1&amp;#946; Plays a Role in the Activation of Peripheral Leukocytes after Blood-Brain Barrier Rupture in the Course of Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) develops when extravasated arterial blood enters subarachnoid space and mixes with cerebrospinal fluid. As a result, many pathologies develop, including increase in brain-blood barrier (BBB) permeability and activation of peripheral leukocytes, that in turn augments immuno-inflammatory response, considered as the cause of numerous complications following SAH. In the study, we examined the role of one of major cytokines, interleukin 1-beta (IL-1beta), in the BBB rupture and subsequent migration of leukocytes into central nervous system (CNS) after experimental SAH in adult rats. SAH was produced by injection of 150 uL of autologous arterial blood into cisterna magna. In 50% of animals, IL-1beta activity was inhibited by intracerebroventricular administration of anti-rat IL-1beta antibodies (SAH' groups). Control group consisted of sham-operated rats. Ninety minutes or 24 hrs following surgery, blood samples were taken, then animals were perfused transcardially and whole brains were collected. Three major populations of leukocytes present at brain stem and frontal part of the brain - granulocytes, monocytes/macrophages and lymphocytes - were labeled with appropriate antibodies. S-100B protein concentration in the serum, a marker of BBB permeability, was also measured. Neutralization of IL-1beta activity reduced elevated S-100B level and number of leukocytes found within the CNS, however these changes were not uniformly significant among different subgroups. The results demonstrate an important role of IL-1beta in the BBB damage and leukocyte migration into the CNS subarachnoid hemorrhage.

C-Reactive Protein Elicits White Blood Cell Activation in Humans

Objective Consistent epidemiologic evidence suggests that acute infections increase the risk for acute cardiovascular events. We tested in humans whether activation of peripheral leukocytes in reaction to the administration of recombinant human C-reactive protein (rhCRP) may provide a mechanism for infectious diseases to promote atherosclerotic disease. Methods and Results By using quantitative real-time polymerase chain reaction analysis, whole-blood expression profiles were analyzed for 95 inflammatory markers before and after infusion of 1.25 mg/kg rhCRP in 5 male volunteers. Relevant transcript levels were measured at baseline and 4 and 8 hours after rhCRP-infusion. CRP caused significant up-regulation of matrix metalloproteinase (MMP)-9, monocyte chemoattractant protein (MCP)-1, plasminogen activator urokinase, macrophage inflammatory protein 1α, and nuclear factor of kappa B inhibitor mRNAs in peripheral leukocytes. mRNA up-regulation of MMP-9 and MCP-1 was 17- and 11-fold, respectively. The corresponding increase in plasma protein levels of MMP-9 (78 ± 32 ng/mL to 109 ± 41 ng/mL; P = .014) and MCP-1 (312 ± 92 pg/mL to 2590 ± 898 pg/mL; P = .007) closely mirrored mRNA findings. Also, in whole-blood culture stimulation assays, CRP induced proinflammatory changes. Notably, heat inactivation abolished the capacity of CRP to evoke these proinflammatory changes, excluding a role for contaminants within the purified CRP preparation. Conclusion CRP elicits activation of peripheral leukocytes with ensuing secretion of plaque-destabilizing mediators. These findings are consistent with the hypothesis that infectious diseases trigger manifestations of atherosclerosis, in which CRP elevation might contribute to the onset of cardiovascular events.

Recombinant T Cell Receptor Ligand Treats Experimental Stroke

Experimental stroke induces a biphasic effect on the immune response that involves early activation of peripheral leukocytes followed by severe immunodepression and atrophy of the spleen and thymus. In tandem, the developing infarct is exacerbated by influx of numerous inflammatory cell types, including T and B lymphocytes. These features of stroke prompted our use of recombinant T cell receptor ligands (RTL), partial major histocompatibility complex Class II molecules covalently bound to myelin peptides. We tested the hypothesis that RTL would improve ischemic outcome in the brain without exacerbating defects in the peripheral immune system function. Four daily doses of RTL were administered subcutaneously to C57BL/6 mice after middle cerebral artery occlusion, and lesion size and cellular composition were assessed in the brain and cell numbers were assessed in the spleen and thymus. Treatment with RTL551 (I-A(b) molecule linked to MOG-35-55 peptide) reduced cortical and total stroke lesion size by approximately 50%, inhibited the accumulation of inflammatory cells, particularly macrophages/activated microglial cells and dendritic cells, and mitigated splenic atrophy. Treatment with RTL1000 (HLA-DR2 moiety linked to human MOG-35-55 peptide) similarly reduced the stroke lesion size in HLA-DR2 transgenic mice. In contrast, control RTL with a nonneuroantigen peptide or a mismatched major histocompatibility complex Class II moiety had no effect on stroke lesion size. These data are the first to demonstrate successful treatment of experimental stroke using a neuroantigen-specific immunomodulatory agent administered after ischemia, suggesting therapeutic potential in human stroke.

Successful Intensive Insulin Treatment of Type 1 Diabetic Dogs Leads to Restoration of Peripheral Leukocyte Insulin Signaling Gene Expression and Enzyme Activities

The purpose of this study was to investigate whether intensive insulin treatment of dogs suffering from type 1 diabetes mellitus, resulting in tight glycemic control, could be reflected by changes in peripheral leukocyte metabolism. Specifically, plasma metabolites and enzyme activities were assessed. In addition, quantitative RT-PCR was used to determine changes in insulin signaling gene (insulin receptor substrate (IRS)-1, IRS-2 and phosphatidylinositol 3-kinase (PI3-K) P85alpha) mRNA levels in peripheral leukocytes. Lastly, leukocyte enzymes involved in cellular energy metabolism were examined for changes in glucose utilization. Our results indicated that intensive insulin treatment was successful in type 1 DM dogs, leading to tight glycemic control. The mean glucose concentration and glycated albumin percentage significantly decreased to 156 mg/dl and 15.6%, respectively, following treatment. In peripheral leukocytes, the IRS-2 and PI3-K p85alpha mRNA levels significantly increased, and a significant increase in pyruvate kinase and pyruvate carboxylase activity, two enzymes involved in cellular energy metabolism, was also observed post treatment. Therefore, the observed changes in insulin signaling pathway activity and cellular energy metabolism enzyme activity in peripheral leukocytes are considered to be characteristics of amelioration of glucose metabolism by insulin action. As such, peripheral leukocytes are sufficiently sensitive to monitor for improving glycemic control during intensive insulin treatment of type 1 DM dogs. Blood cells such as leukocytes are much more readily available than muscle or adipose tissue for studies in dogs.

Fabry's disease: normal alpha-galactosidase activity and urinary-sediment glycosphingolipid levels in two obligate heterozygotes.

SUMMARY A clinical and hiochemical study of twelve persons in the same family, including two hemizygous and one typical heterozygous patients, for Fabry's disease is reported. Two obligate heterozygous females—daughters of the index case—lacked any of the clinical manifestations found in typical heterozygous carriers, having also normal α-galactosidase activity in peripheral leukocytes and normal urinary excretion of trihexosylceramide and digalactosylceramide. Blood group serology was determined to exclude illegitimacy. The validity of these findings and some possible explanations are discussed.

Morbus gaucher: A report of two cases

[corrected] Clinical features of inherited glucocerebrosidase deficiency were first described by Phillippe Charles Ernest Gaucher, French physician (1854-1918). Deficiency of glucocerebrosidase leads to the accumulation of the lipid glucocerebroside within the lysosomes of the monocyte macrophage system. Lipid-laden cells, known as Gaucher cells, lead to hepatosplenomegaly, multiorgan dysfunction and sceletal deterioration. We reported a 36-year-old male and a 42-year-old female admitted for the clinical examination due to hepatosplenomegaly. The Clinical diagnosis was provided by a bone marrow examination and demonstration of the characteristic Gaucher cells. Both of the patients had type I Gaucher's disease (a mild form of the disease), wich is distiguished by the lack of central nervous system involvement and striking phenotypic variation. We had not a possibility of testing beta-glucocerebrosidase activity in peripheral leukocytes (a definitive diagnosis of Gaucher's disease). Also, enzyme replacement therapy had not been available in our country. Althoungh rare, Gaucher's disease is also present in our country. Both molecular genetic, and the enzyme beta-glucocerebrosidase activity testing in peripheral leukocytes are needed for the definitive diagnosis of this disease.

Immunological characteristics of cattle with Mycobacterium avium subsp. paratuberculosis infection

Several years lasting clinical and microbiological monitoring of a cattle herd infected with paratuberculosis allowed to identify three groups of animals showing different courses of the infection. Group N (non-shedders) included animals negative by faecal culture throughout the monitoring period. Animals of Group L (low shedders) shed sporadically small quantities of mycobacteria (1 to 9 CFU), but remained clinically healthy throughout the monitoring period. Group H (high shedders) included animals shedding repeatedly large quantities of Mycobacterium avium subsp. paratuberculosis (10 CFU) with a progressive deterioration of the state of health in most of them. Animals with specific antibodies detected by agar gel immunodiffusion and complement fixation test were found in all groups, but the percentage of serologically positive animals was higher in animals of Group L and significantly higher (p &amp;lt; 0.01) in animals of Group H than in animals of Group N. Specific cell-mediated immunity was demonstrated especially in the group of low shedders (Group L), the differences&amp;nbsp;in the percentages of interferon gamma assay positive animals in this group and other groups was highly significant (p &amp;lt; 0.01). Only insignificant differences in the counts and activity of peripheral leukocytes were found among groups of clinically healthy animals differing in intensity of M.&amp;nbsp;paratuberculosis shedding. However, the progressive development of clinical signs of paratuberculosis in Group H was associated with a significant (p &amp;lt; 0.01) decrease of lymphocytes and monocytes, a non-significant decrease of neutrophils, a significant (p &amp;lt; 0.05) increase in the percentage of CD4&lt;sup&gt;+&lt;/sup&gt; cells and a insignificant decrease in the percentage of CD8&lt;sup&gt;+&lt;/sup&gt; cells; consequently the CD4/CD8 ratio increased.

Actividad de la telomerasa en leucocitos de sangre periférica de pacientes con hipertensión arterial esencial

Primary or secondary activation of the immune mechanisms that lead to proliferation and dysfunction of specific cellular groups appears to be involved in the pathogenesis and complications of essential hypertension. In view of the evidence that, on one hand, telomeric length determines the replicative capacity and life span of cells and, on the other hand, idiopathic hypertensive patients have peripheral white cell replicative disorders, we decided to investigate the relationship between the influence of telomerase activity in peripheral leukocytes as an indirect marker of telomeric length and the presence of arterial hypertension. Telomerase activity in peripheral white blood cells was measured in healthy individuals, in effectively treated hypertensive patients and in a non-well controlled hypertensive group. White blood cells were separated through a density gradient, then lysed and their DNA amplified by a polimerase chain reaction (PCR). Telomerase activity was determined with an ELISA specific kit. The white blood cell count was higher in the hypertensive than the control group (p < 0.05). Telomerase activity was positive in all three groups but higher in patients under 45 year-old with bad controlled hypertension as compared with healthy individuals and patients under 45 year-old with well controlled hypertension (p < 0.05); in the latter group, telomerase activity was significantly lower than in the other groups (p < 0.05). Our results indicate that there exists a relationship between telomerase activity in peripheral leukocytes, the proliferation of these white blood cells and the presence of essential arterial hypertension.

Cytosolic ratio of malate dehyrogenase/lactate dehydrogenase activity in peripheral leukocytes of race horses with training

The activities of the enzymes involved in the malate–aspartate shuttle and m RNA expression of malate dehydrogenase (MDH), a crucial enzyme for the NADH shuttle that produces ATP in glucose metabolism in the peripheral leukocytes of horses, were measured to investigate the change in metabolic states with training. There were no significant differences in plasma glucose and immunoreactive insulin concentrations between race horses and riding horses, used as a comparable reference. The cytosolic and mitochondrial MDH activities in leukocytes of race horses were significantly higher than those of riding horses. High activities of MDH in leukocytes of race horses were confirmed by RT - PCR analysis on the total RNA extracted from the whole blood. The cytosolic ratio ofMDH /lactate dehydrogenase (LDH) activity (M/L ratio) in leukocytes of race horses was significantly higher than in those of riding horses. Increase in the M/L ratio was considered to reflect elevation of energy metabolism in animal tissues. The M/L ratio may be a useful parameter to evaluate the difference in metabolic states between race horses and riding horses.