The interaction between oxidative stress and mast cell activation plays a role in acute lung injuries induced by intestinal ischemia-reperfusion.

BACKGROUND: Both oxidative stress and mast cells are involved in acute lung injuries (ALIs) that are induced by intestinal ischemia-reperfusion (IIR). The aim of this study was to further investigate the interaction between oxidative stress and mast cells during the process of IIR-induced ALI. MATERIALS AND METHODS: Thirty adult Sprague-Dawley rats were randomly divided into five groups: sham, IIR, IIR + compound 48/80 (CP), N-acetylcysteine (NAC) + IIR, and NAC + IIR + CP. All rats except those in the sham group were subjected to 75 min of superior mesenteric artery occlusion, followed by 2 h of reperfusion. The rats in the NAC + IIR and NAC + IIR + CP groups were injected intraperitoneally with NAC (0.5 g/kg) for three successive days before undergoing IIR. The rats in the IIR + CP and NAC + IIR + CP groups were treated with CP (0.75 mg/kg), which was administered intravenously 5 min before the reperfusion. At the end of the experiment, lung tissue was obtained for pathologic and biochemical assays. RESULTS: IIR resulted in ALI, which was detected by elevated pathology scores, a higher lung wet-to-dry ratio, and decreased expression of prosurfactant protein C (P < 0.05). Concomitant elevations were observed in the expression levels of the nicotinamide adenine dinucleotide phosphate oxidase subunits p47(phox) and gp91(phox) and the levels of hydrogen peroxide and malondialdehyde. However, superoxide dismutase activity in the lung was reduced (P < 0.05). The level of interleukin 6, the activity of myeloperoxidase, and the expression of intercellular adhesion molecule 1 were also increased in the lung. IIR led to pulmonary mast cell degranulation and increases in the plasma and pulmonary ß-hexosaminidase levels, mast cell counts, and tryptase expression in lung tissue. CP aggravated these conditions, altering the measurements further, whereas NAC attenuated the IIR-induced ALI and all biochemical changes (P < 0.05). However, CP abolished some of the protective effects of NAC. CONCLUSIONS: Oxidative stress and mast cells interact with each other and promote IIR-induced ALI.

Microheterogeneity of serum ß-hexosaminidase in chronic alcohol abusers in a driver's license regranting program.

BACKGROUND: Carbohydrate-deficient transferrin (CDT) is one of the best indicators for chronic alcohol abuse and detection of relapse. In this study, we explore the microheterogeneity of ß-hexosaminidase (ß-HEX) in chronic alcohol abusers in the framework of a driver's license regranting program. Studies have shown that increased serum activity of ß-HEX B (isoforms P, I, and B) may be a sensitive marker for chronic alcohol abuse. Here, we describe methodology, limitations, and correlation of ß-HEX isoforms with CDT. METHODS: CDT was assayed at the central laboratory of the Ghent University Hospital by capillary zone electrophoresis, measured on the Capillarys 2™ system and was expressed as a percentage of total serum transferrin (%CDT). Serum of chronic alcohol abusers was compared to nonheavy drinkers using agarose gel isoelectric focusing (IEF). Total ß-HEX activity was assayed fluorimetrically following preparative IEF in 81 subjects. ß-HEX isoforms were investigated and compared between nonheavy drinkers and heavy drinkers. RESULTS: Agarose gel IEF shows additional cathodal bands in serum of chronic alcohol abusers. Mean total ß-HEX activity between pH 6.8 and 7.7, designated as HEX-7, showed the highest correlation with %CDT (r = 0.70, p < 0.0001, n = 68). In a selected subgroup, where CDT could not be quantified (n = 13) because of an atypical electropherogram, HEX-7 was in concordance with either estimated %CDT value or liver enzyme activities. CONCLUSIONS: In this proof-of-concept study, we introduce a novel approach to quantify ß-HEX isoforms using preparative IEF and fluorimetry. A highly significant correlation of HEX-7 and %CDT has been found. Because of exclusion of the P isoform, HEX-7 could be a useful supplementary marker for detecting chronic alcohol abuse.

The mechanism of sevoflurane preconditioning-induced protections against small intestinal ischemia reperfusion injury is independent of mast cell in rats.

The study aimed to investigate whether sevoflurane preconditioning can protect against small intestinal ischemia reperfusion (IIR) injury and to explore whether mast cell (MC) is involved in the protections provided by sevoflurane preconditioning. Sprague-Dawley rats exposed to sevoflurane or treated with MC stabilizer cromolyn sodium (CS) were subjected to 75-minute superior mesenteric artery occlusion followed by 2-hour reperfusion in the presence or absence of MC degranulator compound 48/80 (CP). Small intestinal ischemia reperfusion resulted in severe intestinal injury as demonstrated by significant elevations in intestinal injury scores and p47(phox) and gp91(phox), ICAM-1 protein expressions and malondialdehyde and IL-6 contents, and MPO activities as well as significant reductions in SOD activities, accompanied with concomitant increases in mast cell degranulation evidenced by significant increases in MC counts, tryptase expression, and ß-hexosaminidase concentrations, and those alterations were further upregulated in the presence of CP. Sevoflurane preconditioning dramatically attenuated the previous IIR-induced alterations except MC counts, tryptase, and ß-hexosaminidase which were significantly reduced by CS treatment. Furthermore, CP exacerbated IIR injury was abrogated by CS but not by sevoflurane preconditioning. The data collectively indicate that sevoflurane preconditioning confers protections against IIR injury, and MC is not involved in the protective process.

Ym1, an eosinophilic chemotactic factor, participates in the brain inflammation induced by Angiostrongylus cantonensis in mice.

Angiostrongylus cantonensis is an emerging zoonotic pathogen that has caused hundreds of cases of human angiostrongyliasis worldwide. The larva in nonpermissive hosts cannot develop into an adult worm and can cause eosinophilic meningitis and ocular angiostrongyliasis. The mechanism of brain inflammation caused by the worm remains poorly defined. According to previous data of GeneChip, Ym1 in the brain of mice 21 days after infection with A. cantonensis was highly upregulated to over 7,300 times than the untreated mice. Ym1 is an eosinophilic chemotactic factor with the alternative names of chitinase-3-like protein 3, eosinophil chemotactic cytokine, and ECF-L. Ym1 displays chemotactic activity for T lymphocytes, bone marrow cells, and eosinophils and may favor inflammatory responses induced by parasitic infections and allergy. It has been reported that Ym1 is synthesized and secreted by activated macrophages during parasitic infection (Chang et al., J Biol Chem 276(20):17497-17506, 2001). In the brain, microglia are alternatively activated macrophage-derived cells which are the key immune cells in central nervous system inflammation. To explore the role of Ym1 in inflammation caused by A. cantonensis-infected mice, we examined the levels of Ym1 in the sera and cerebrospinal fluid (CSF) of the infected animals, followed by detection of the mRNA expression level of Ym1 in various organs including the brain, lung, liver, spleen, and kidney and of the cytokines IL-5 and IL-13 in the brain of the infected mice with or without intraperitoneal injection of minocycline (an inhibitor of microglial activation) by real-time reserve transcription PCR. Furthermore, immunolocalization of Ym1 in the brains of the infected mice was observed by using a fluorescence microscope. Our results showed that Ym1 was most highly expressed in the brains and CSF of the infected mice along with the process of inflammation. The antibody localized Ym1 to the microglia in the brain of the mice in both infection and minocycline + infection groups. And as in the brain, the mRNA level of Ym1 changed more obviously than IL-5 and IL-13. The study implies that Ym1 might serve as an alternative potential pathological marker which is detected not only in the sera and CSF but also in the brains of the infected mice and Ym1 secreted by microglia might be involved in eosinophilic meningitis and meningoencephalitis caused by A. cantonensis infection.

Mucolipidosis type III in an adolescent presenting with atypical facial features and skeletal deformities.

Mucolipidosis type III (MLIII) (MIM# 252600) is an uncommon autosomal recessive disorder that results from deficiency of the multimeric enzyme, UDP-N-acetylglucosamine-1-phosphotransferase. The enzymatic defect results in deficiencies of lysosomal degradative enzymes with concomitant intracellular accumulation of both partly degraded glycosaminoglycans and sphingolipids leading to clinical manifestations such as short stature, developmental delay and other structural abnormalities. The diagnosis is challenging since musculoskeletal presentation may mimic some of the rheumatic and metabolic disorders. We herein report on a 13-year-old adolescent who was admitted to our rheumatology clinic because of progressive joint stiffness and deformities of her hands. The clinical and radiological findings led us to the diagnosis of MLIII despite negative urinary aminoglycosyaminoglycans. Therefore we decided to check for the presence of elevated activities of alpha-mannosidase and beta-hexosaminidase A+B in the plasma which was actually the case and confirmed the clinical diagnosis ofMLIII.

Effect of sample collection, temperature and time of storage on ß-galactosidase and total hexosaminidase activities in dried blood collected on filter paper.

BACKGROUND: Dried blood spots (DBS) on filter paper is a valuable sampling technique in clinical chemistry, but the stability of enzymes used in the diagnosis of lysosomal storage diseases (LSDs) needs to be evaluated. METHODS: In a first experiment, blood from 20 subjects was collected using a syringe without additives and distributed into EDTA tubes, heparin tubes, and spotted on filter paper for the comparison of sampling effects. In a second experiment, blood from 30 healthy subjects was spotted on filter paper and analyzed for ß-galactosidase and total hexosaminidase activities after storage of the samples at different temperatures for up to 180 days. RESULTS: Initially, we observed that enzyme activities were the same, independent of the collection method. When DBS was stored at 37°C the activity of ß-galactosidase dropped to 85% of the initial value after 180 days (p<0.05). At all other temperatures (-20°C, 4°C and 25°C), the results were within the methodological error. Total hexosaminidase activity did not change significantly during the entire study period and at different storage temperatures. CONCLUSIONS: The two enzymes investigated in the present study may be stored for up to 17 days (ß-galactosidase) or 180 days (total hexosaminidase) until analysis without loss of activity.

N-acetyl-beta-D-hexosaminidase and its isoenzymes A and B in blood serum and urine, as a potential colon cancer markers.

BACKGROUND/AIMS: Evaluation of N-acetyl-beta-D-hexosaminidase (HEX), and its isoenzymes A (HEX A) and B (HEX B) activity in blood serum and urine as potential markers of colorectal cancer. METHODOLOGY: The study was performed in blood serum and urine of 32 patients with adenocarcinoma, 6 with adenocarcinoma mucinosum of the colon, and 20 healthy people. The activity of HEX, HEX A and HEX B was determined in blood serum and urine by spectrophotometric method of Marciniak et al. The concentration of CEA was determined in blood serum by immunoenzymatic method (MEIA). The concentration of protein was assessed by the Lowry method, whereas the concentration of creatinine in urine by the Jaffe method (without deproteinization). RESULTS: A significant increase in the concentration of HEX, HEX A and HEX B activity was proved in serum and urine of patients with colon adenocarcinoma. In patients with colon adenocarcinoma mucinosum, the higher activity of HEX was revealed in blood serum compared to healthy people, and the significantly higher activity of HEX and HEX B expressed as pKat/mg of creatinine, was found in urine. We observe a significant increase in the activity of HEX, HEX A and HEX B expressed in pKat/mg of creatinine was found in urine of patients bearing tumor of diameter 6.0-7.0 cm in comparison to patients with tumor of diameter 4.0-5.0 cm. CONCLUSIONS: The present study results suggest that determination of HEX, HEX A and HEX B activity in blood serum and urine may be used to detect colon cancer in its early stages. However, the use of HEX, HEX A and HEX B activity in oncological diagnostics requires further studies on a larger group of patients.

Altered regulation of serum lysosomal acid hydrolase activities in Parkinson's disease: A potential peripheral biomarker?

INTRODUCTION: Recent studies have indicated that lysosomal dysfunction contributes to the development of idiopathic Parkinson's disease (PD). It is uncertain whether dysregulation of serum lysosomal acid hydrolase activity exists in sporadic PD patients compared with normal controls (NCs) and parkinsonian syndrome (PS) patients. METHODS: Sporadic PD patients without GBA1 mutations (n = 68) were matched with normal controls (n = 45), and parkinsonian syndrome patients (n = 32) in terms of family history, age, and sex. We measured the activities of lysosomal enzymes, α-galactosidase, ß-galactosidase, and ß-hexosaminidase and examined the possible correlations between lysosomal acid hydrolase activities with age in NCs, PD, and PS patients. RESULTS: ß-Galactosidase activity was significantly higher in the PD and PS than in the NC group (P < 0.001). The ß-galactosidase to α-galactosidase and ß-hexosaminidase to ß-galactosidase activity ratios were more useful for distinguishing PD and PS patients from NCs (P < 0.0001). Furthermore, α-galactosidase activity was significantly higher in PS patients than both PD and NC groups (p = 0.04). ß-Galactosidase and α-galactosidase activities exhibited a statistically significant negative correlation with age in NCs, and ß-hexosaminidase activity showed a positive correlation with age in PS. However, PD patients did not show any of these correlations. CONCLUSION: Our results suggest the presence of an unknown regulatory mechanism(s) of serum acid hydrolase activities with aging in the normal population and abnormalities in their regulation in PD and PS patients. However, the pattern of dysregulation in these two groups is different. Thus, serum lysosomal acid hydrolase activity can be used as a peripheral biomarker for PD.

N-acetyl-beta-hexosaminidase activity in asthma.

BACKGROUND: N-acetyl-beta-hexosaminidase (beta-hex) is a lysosomal hydrolase, which is selectively secreted into the extracellular space by inflammatory cells. The aim of our study was to assess the activity of beta-hex in the plasma of asthmatic patients, and to establish whether it correlates with asthma severity and airway inflammation. METHODS: The study was conducted in a group of 46 asthmatic patients and 13 healthy volunteers. All study participants underwent analysis of exhaled nitric oxide and flow-volume spirometry. beta-hex activity, peripheral blood eosinophils, total serum IgE and eosinophil cationic protein were analyzed in blood samples from all asthmatic patients and healthy volunteers. RESULTS: beta-hex activity was significantly higher in patients with severe or moderate asthma compared with healthy volunteers and was positively correlated with exhaled nitric oxide levels and serum eosinophil cationic protein in these groups of patients. There was no correlation between beta-hex activity and forced expiratory volume in 1 s, blood eosinophil count or total serum IgE in these groups of asthmatics. CONCLUSIONS: Our results suggest that beta-hex could take part in airway inflammation and remodeling in asthma. Our study is the first report in which the elevated activity of beta-hex in subjects with asthma has been observed. However, more studies are needed to establish the precise role of this enzyme in asthma in humans.

The effect of the binge drinking session on the activity of salivary, serum and urinary beta-hexosaminidase: preliminary data.

Our report is the first to show that an acute ingestion (6 h) of a relatively large, yet tolerable dose of alcohol (120-160 g), significantly increases activity of total serum beta-hexosaminidase (total beta-HEX), beta-HEX A and beta-HEX B isoenzymes, as well as salivary total beta-HEX and urinary beta-HEX A, in eight infrequent binge drinkers. An increase in the activity of serum and urinary total HEX is mainly due to its secretory isoenzyme beta-HEX A.

Reference Data on Neonatal Serum N-Acetyl-ß-hexosaminidase Activity.

BACKGROUND: Determination of neonate serum's N-acetyl-ß-hexosaminidase (HEX) activity and correlation results with Apgar scale and factors routinely determined in newborn serum. AIMS: Providing reference values of neonates serum HEX activities, and indicate their diagnostic significance. STUDY DESIGN: The study was performed using random serum samples of 111 infants (53 ♂/58 ♀), aged 1-30 days. The activity of HEX was determined colorimetrically and expressed in nKat/L. RESULTS: Serum HEX activity of 111 newborns was 360.5 ± 114.0 nKat/L and significantly positively correlated with gestation week at the day of delivery, birth weight, weight on day of blood collection, sex, and serum CRP. CONCLUSIONS: Reference values presented for neonatal serum activities of HEX may be used in neonatal diagnostics, for example, to detect inflammation and other diseases or for early assessment of the risk of Tay-Sachs and Sandhoff diseases.

Positive Correlation of Serum N-Acetyl-ß-hexosaminidase with Markers of Atherosclerosis in Diabetes Type 2 Patients with Mild Symptoms of Depression and Anxiety.

BACKGROUND: Analysis of the correlation between diabetes type 2 (DT2) and serum N-acetyl-ß-hexosaminidase (HEX) activity with parameters of fat metabolism and symptoms of anxiety and depression. MATERIAL AND METHOD: The study was performed using a random sample of 40 DT2 patients (22 women and 18 men) between the ages of 43 and 71 (median 59) and 40 control persons (28 women and 12 men) between the ages of 18 and 64 (median 46). The activity of HEX was determined by a colorimetric method. The activity of the serum exoglycosidase was expressed in pkat/mL. Each participant underwent Hamilton tests, to evaluate level of anxiety and depression. Additionally, the HEX activity and concentration of particular lipidograms were monitored using a blood sample from each participant. RESULTS: In DT2 patients, a significant positive correlation was found between serum HEX activity and the concentration of serum cholesterol LDL fractions, triacylglycerols (TAG), and Castelligro atherogenic indexes. A significantly increased level of anxiety and depression in comparison to the control group was found as well. CONCLUSION: Serum HEX activity in DT2 patients is a better marker of atherosclerosis than serum total cholesterol level in persons with mild symptoms of depression and anxiety. In DT2 patients, a routine testing of anxiety and depression is recommended. Early detection of these disorders creates the possibility for treatment, an improvement in a patient's quality of life, and the overall longevity of DT2 patients.

Specific correction of impaired acid hydrolase secretion in storage pool-deficient platelets by adenosine diphosphate.

Storage pool-deficient (SPD) platelets, which have decreased amounts of dense-granule and/or alpha-granule constituents, contain normal amounts of lysosomal acid hydrolases, but in some cases exhibit impaired secretion of these enzymes. We examined this impaired secretion response in SPD patients with varying extents of granule deficiencies, and determined the effects of added dense-granule constituents. Acid hydrolase secretion was impaired in patients with severe dense-granule deficiencies, but not in patients with lesser dense-granule deficiencies, including those with alpha-granule deficiencies as well. When dense-granule constituents (ADP, ATP, serotonin, Ca+2, pyrophosphate) were added to gel-filtered platelets, ADP, but none of the other constituents, completely corrected the impairment of thrombin and A23187-induced secretion in SPD platelets. The concentration of ADP required to normalize thrombin-induced secretion varied markedly, from 0.01 to 10 microM, among the individual patients. Fixation of platelets with formaldehyde before centrifugation did not prevent the enhancement of secretion by ADP. Excess ATP, which acts as a specific antagonist of ADP-mediated responses, completely blocked this enhancement of secretion in SPD platelets by ADP, and partially inhibited acid hydrolase secretion induced by low, but not high, concentrations of thrombin in normal platelets as well. Treatment of normal platelets with acetylsalicylic acid in vivo, but not in vitro, produced an impairment of acid hydrolase secretion similar in extent to that in SPD platelets, but which could not be completely corrected by added ADP. One possible explanation of these results is that the impairment of acid hydrolase secretion may be secondary to the dense-granule deficiency in SPD platelets, and that secreted ADP may potentiate the lysosomal secretion response in normal platelets as well.

Isoenzyme pattern and partial characterization of hexosaminidases in the membrane and cytosol of human erythrocytes.

OBJECTIVES: Hexosaminidase activity is present in lysosomes, plasma membrane and cytosol of many human cells. Plasma membrane and cytosolic hexosaminidase is not well characterized, particularly as regards their isoenzyme forms and their relationship with the lysosomal ones. DESIGN AND METHODS: Erythrocyte hexosaminidase isoforms were chromatographically separated, characterized and compared to those in the plasma of healthy individuals and in the erythrocytes of a Tay-Sachs patient. RESULTS: Hexosaminidase isoenzymes were found in plasma membrane and cytosol and were composed of the same alpha- and beta-subunits as the lysosomal and plasma hexosaminidase A and B isoenzymes, though with some structural and kinetic differences. In addition, the cytosol contained a hexosaminidase that is a specific N-acetyl-beta-D-glucosaminidase, the one involved in the removal of N-acetylglucosamine residues O-linked to proteins, named O-GlcNAcase. CONCLUSIONS: This work provides an additional step in the characterization of hexosaminidases helping better understand their role in non-lysosomal compartments and their involvement in physiological or pathological situations.

[Concentration of thyroid stimulating hormone and activity of N-acetyl-beta-D-hexosaminidase and its isoenzymes, in serum of patients with thyroid cancer]. / Stezenie hormonu tyreotropowego oraz aktywnosc N-acetylo-beta-D-heksozoaminidazy i jej izoenzymów A i B w surowicy chorych na raka tarczycy.

UNLABELLED: Thyroid cancer consists 1% of all malignant neoplasms. It is not known interrelationship between concentration of TSH in blood serum and condition of thyroid cancer. Thyroid cancer is difficult for diagnosis and differentiation. Therefore it is necessary to search for biochemical markers helpful in diagnostics of thyroid cancer. Significant increase in activity of N-acetyl-beta-D-hexosaminidase and its isoenzymes A and B in serum of patients with neoplasms of kidney and pancreas suggest approporiateness of evaluation of HEX and its isoenzymes in diagnostics of thyroid cancer. THE AIM: of the study--evaluation of TSH concentration and activity of HEX and its isoenzymes A and B, in serum of patients with thyroid cancer. MATERIALS AND METHODS: Blood was taken from 7 patients with thyroid cancer (6 men and 1 woman). Control consisted of 7 healthy men. In blood serum concentration of TSH was determined with immunoenzymatic method on analyzer Axsym of Abbott and expressed in microU/mL. The activity of HEX and its isoenzymes A and B was determined by method of Chatterjee et al., as modified by Zwierz et.al. Determination of HEX was performed on microplate reader ELX800 BIO-TEK. Activity of HEX, HEX A and B was expressed in pKat/mL, and specific activity in pKat/mg protein). Protein was determined by biuret method and results were expressed in mg/mL. RESULTS: Concentration of HEX A activity in serum of thyroid cancer patients is significantly higherin comparison to healthymen (p = 0.0191). Also specific activity of HEX A in serum of thyroid cancer patients is significantly higher in comparison to healthy men (p = 0.0393). CONCLUSIONS: 1. Determination of TSH concentration in serum of thyroid cancer before the operation may confirm euthyreosis. 2. Determination of HEX A activity in serum may be helpful in diagnostics of thyroid cancer.

Determination of N-acetyl-ß-hexosaminidase in serum from hemolyzed blood.

BACKGROUND: Determination of lysosomal N-acetyl-ß-hexosaminidase (HEX) in serum from hemolyzed blood, creates serious analytical problems, because hemoglobin absorbs light at a similar wavelength like 4-nitrophenol, which is released from artificial substrate. OBJECTIVE: The objective of the work was to adapt a manual method to allow analysis of HEX in hemolyzed samples. METHODS: Serums without and with hemolysis were incubated with 4-nitrophenol-N-acetylglucosamine as a substrate. Released 4-nitrophenol was determined colorimetrically. After the incubation of the serum from hemolyzed blood with substrate, hemoglobin was precipitated with trichloroacetic acid (TCA) before 4-nitrophenol determination. RESULTS: The mean concentration of HEX activity in non-hemolyzed and hemolyzed blood of the same patients, determined with non-modified and modified methods had no significant differences, and they are: 243.12±119.76 and 233.99±108.76pkat/mL, respectively. A coefficient of correlation between non-modified and modified methods equals the 0.98. For HEX determination with the modified method in serum from hemolyzed blood, optimal reaction time was 60min, pH of reaction mixture was 4.7, and Km was 0.11mMm. CONCLUSION: HEX determinations in the same serums from non-hemolyzed blood by the non-modified method and hemolyzed blood with the modified method, gave similar results with a 0.98 coefficient of correlation. The modified method is appropriate for HEX determination in serum from hemolyzed blood.

Leukocyte glucocerebrosidase and ß-hexosaminidase activity in sporadic and genetic Parkinson disease.

BACKGROUND: Recent reports have shown that the activities of lysosomal enzymes are altered in the CNS of sporadic PD (sPD) without GBA mutations. We hypothesized that the activities of lysosomal enzymes are altered in peripheral blood leukocytes (PBLs) of patients with sPD and other genetic parkinsonism. METHODS: Glucocerebrosidase and ß-hexosaminidase activities in PBLs were measured in 36 patients with sPD, 5 PD patients with PARK2 mutations, 10 patients with spinocerebellar ataxia (SCA) 17 with parkinsonism, and 20 healthy controls. RESULTS: The glucocerebrosidase and ß-hexosaminidase activities were not different in patients with sPD, PD with PARK2 mutations, and SCA17 with parkinsonism from those of the controls. In the patients with sPD, the activity of GCase was positively correlated with disease duration. CONCLUSION: The glucocerebrosidase and ß-hexosaminidase activities in PBLs cannot be used as a biomarker in sPD and other genetic parkinsonism.

Plasma tumor necrosis factor-a (TNF-a) levels in Gaucher disease.

Tumor necrosis factor-a (TNF-a) levels were measured in the plasma of patients with different types of Gaucher disease (GD) and patients with other lysosomal storage diseases. The highest TNF-a levels were observed in the most severe neuronopathic type of GD, exceeding those found in healthy individuals as well as patients with other lysosomal disorders. Type I GD cases showed a wide range of TNF-a levels ranging from normal to 2.5 x the highest control value. TNF-a is a pleiotropic cytokine produced mainly by activated macrophages. Our data suggest that it may play a role in the pathophysiology of GD disease.

Beta-hexosaminidase isoenzyme profiles in serum, plasma, platelets and mononuclear, polymorphonuclear and unfractionated total leukocytes.

OBJECTIVES: The relative proportion in percentage of the isoenzyme A of beta-hexosaminidase (Hex) is the single discriminatory function most frequently used for the biochemical screening of heterozygote Tay-Sachs disease carriers. It has been suggested that the assay of the Hex isoenzymes in homogeneous cell preparations is preferable to that in mixed total leukocytes which present greater interindividual variation. The major aim of our study was the evaluation of this hypothesis. DESIGN AND METHODS: Total Hex and its Hex A and Hex B isoenzymes were determined in different samples of serum and plasma (n = 81) as well as in lysates of platelets (n = 75), and mononuclear (n = 81), polymorphonuclear (n = 81) and mixed total leukocytes (n = 33). RESULTS: The interindividual variations found for % Hex A in the different biological samples were: plasma (CV = 23.4%), platelets (CV = 10.2%), mononuclear (CV = 5.7%), polymorphonuclear (CV = 5.3%) and total leukocytes (CV = 7.1%). Although the relative proportion of Hex A was significantly greater in polymorphonuclear than in mononuclear leukocytes (P < 0.001), a statistical significance was not attained for the correlation between the relative proportions of blood polymorphonuclear cells and Hex A in mixed total leukocytes (r = 0.220). CONCLUSIONS: The use of total leukocyte lysates does not appear to introduce a significant increase for the interindividual variation of the Hex A isoenzyme relative proportion in relation to the use of homogeneous cell preparations.

[Activity of N-acetylo-beta-hexosamninidase in joint fluid from knee and serum of patients with rheumatoid arthritis and osteoarthritis]. / Aktywnosc N-acetylo-beta-heksozoaminidazy w plynie stawowym i surowicy krwi chorych z reumatoidalnym zapaleniem stawów i artroza.

N-acetyl-beta-hexosoaminidase (Hex) is a lysosomal enzyme which releases N-acetylaminohexose from non reducing end of glycosaminoglycans, glycoproteins and glycolipids, taking part in degradation of these substances. It is not known what role Hex plays in the degradation of joints in rheumatoid arthritis and osteoarthritis. The aim of our work was evaluation of Hex activity in synovial fluid and serum of patients with rheumatoid arthritis and osteoarthritis. The investigation was performed on material taken from 28 patients with rheumatoid arthritis aged 22-74 years with III or IV stage of disease and 26 patients with osteo-arthritis aged 41-75 years. The synovial fluid was collected from the knee joint during puncture. Hex activity was also determined in serum of healthy people at the age 25-40 years which constitute a control group. Hex activity was determined by the method of Chatterjee et al. modified by Zwierz et al. The concentration of Hex activity in synovial fluid of patients with rheumatoid arthritis was 15.2 nmol/ml/min and 3-4 times excedeed the serum value in these patients. In osteoarthrosis patients Hex concentration in synovial fluid was 6.15 nmol/ml/min. In serum of all investigated groups, concentration of Hex activity was 4.0-4.7 nml/ml/min. The specific activity of Hex (calculated as a constant amount of protein) in synovial fluid of patients with rheumatoid arthritis was significantly higher than in serum of these persons (p<0.017 and 0.014 respectively).