Decreased Activity of Blood Acid Sphingomyelinase in the Course of Multiple Myeloma.

Acid sphingomyelinase (aSMase) is involved in the generation of metabolites that function as part of the sphingolipid signaling pathway. It catalyzes the breakdown of sphingomyelin into ceramide, a bioactive lipid that, among other roles, is involved in regulation of apoptosis. Dry drop blood test (DBS) and colorimetric 2-step enzymatic assay were used to assess the activity of human blood aSMase, beta-galactosidase, and beta-glucosidase, these enzymes are lysosomal hydrolases that catalyze the degradation of related sphingolipids, of sphingolipid signaling molecules. Blood was collected from a group of healthy volunteers and patients that were diagnosed with multiple myeloma (MM) in various stages of the disease. Additionally, activity of those enzymes in patients diagnosed with other hematological cancers was also assessed. We found that aSMase activity in the blood of patients with MM (at the time of diagnosis) was 305.43 pmol/spot*20 h, and this value was significantly lower (p < 0.030) compared to the healthy group 441.88 pmol/spot*20 h. Our collected data suggest a possible role of aSMase in pathogenesis of MM development.

The modulation of inflammatory parameters, Brain-derived neurotrophic factor levels and global histone H4 acetylation status in peripheral blood of patients with Gaucher disease type 1.

OBJECTIVES: Gaucher's disease type 1 (GD1) pathophysiology includes an imbalance on brain-derived neurotrophic factor (BDNF) levels and in the inflammatory system. However, the pathways involved remain poorly understood. The hypothesis of this study is that epigenetic mechanisms might be involved, at least partially, in this phenomenon. DESIGN AND METHODS: This study investigated the BDNF modulation, global histone H4 acetylation and pro- and anti-inflammatory cytokines levels in the peripheral blood of GD1 patients (n=10) when compared with control samples (CS) (n=11). RESULTS: The results showed a significant increase in Chitotriosidase (CT) (p=0.019) and decreased ß-glucosidase (GBA) activities (p=0.001) in GD1 samples when compared to CS, for GD1 diagnostic confirmation. Reduced levels of BDNF (p=0.004) and elevated levels of TNF-α (p=0.017) and IL-4 (p=0.035) were also found in the GD group. No significant differences were observed in IL-6 or IL-17a levels between groups (p>0.05). Finally, a trend on higher global histone H4 acetylation levels (p=0.054) was observed in the control group when compared to GD1 individuals. CONCLUSIONS: Combined, these results suggest inflammatory cytokines imbalance, reduced BDNF levels and global histone H4 hypoacetylation status in GD type 1 physiopathology. These preliminary findings may open new avenues to introduce therapies and strategies in the preventive management and treatment of this population.

Validity of ß-D-glucosidase activity measured in dried blood samples for detection of potential Gaucher disease patients.

OBJECTIVES: Gaucher disease (GD) diagnosis relies on the demonstration of deficient ß-D-glucosidase (GBA) activity in cellular homogenates. Diagnosis process, however, can be delayed as (i) some GD symptoms are non-specific; and (ii) diagnostic tests are performed in specialized laboratories. These difficulties negatively impact on timely access of patients to therapy. GBA assay in dried blood spots (DBS) represents a method facilitating early identification of patients who will be finally diagnosed with gold standard assay of nucleated cells. Aim of this study is to investigate the DBS analytical performance compared with gold standard method. DESIGN & METHODS: A cross-sectional study started by comparing data of 50 DBS and 50 homogenate samples from the same subjects (25 known-GD and 25 controls). The subsequent phase examined 443 DBS samples. Along with these, 73 blood samples were sent for leukocyte separation and/or EBV-lymphoblast cell lines, and 1 skin biopsy for fibroblast cell lines. Overall the study included a total of 493 subjects. RESULTS: While the results from this first validation group did not yield false positive/negative values, when the analysis was extended to 443 DBS, 14.4% (64 samples) of positive results was yielded. Among these, only 15 were confirmed as GD values with gold standard test. In addition, a thorough examination of some clinical data also revealed 2 false negative results which were confirmed by both enzymatic and molecular analyses. CONCLUSIONS: DBS test could be useful as screening method although with cautions, whereas the standardized GBA assay should remain the gold standard for laboratory diagnosis of Gaucher disease.

Suppression of tumor growth and invasion in 9,10 dimethyl benz(a) anthracene induced mammary carcinoma by the plant bioflavonoid quercetin.

Administration of quercetin, a common polyphenolic component of many vascular and edible plants including vegetables, fruits and tea significantly reduced the tumor volume in rats induced for mammary carcinoma using dimethyl benz (a) anthracene (DMBA). Dose response was assessed, by treating the animals with different doses (15-45 mg/kgbw) of quercetin and 25 mg/kgbw was taken as effective dose. Quercetin was administered as an intra tumoral injection once a week for 4 weeks. Serum levels of carcino embryonic antigen (CEA), a potent marker for tumor growth and invasion was significantly decreased on quercetin treatment. Quercetin caused a significant decrease in the activities of acid phosphatase and Cathepsin D in serum of experimental animals. Activities of lysosomal enzymes- (beta-D galactosidase, beta-D glucuronidase, beta-D glucosidase and sialidase), in serum and tissue were significantly altered in DMBA animals compared to control animals. However, quercetin treatment caused no significant change in lysosomal enzyme activities in tissues, whereas the activities were significantly lowered in serum. Partial purification of tissue type plasminogen activator (t-PA) from the tumor and kidney showed increased activity in the DMBA induced animals. Serum urokinase, -like plasminogen activator (u-PA) was also increased in animals with tumor, indicating tumor invasion. Administration of quercetin caused a significant decrease of both t-PA and u-PA. In conclusion, the present study suggests the possible role of quercetin in primary and invasive mammary tumor treatment. The above observations in vivo warrant further studies, due to the easy availability, common occurrence and low toxicity of this dietary bioflavonoid.

Low levels of occupational exposure to arsenic and antimony: effects on lysosomal glycohydrolase levels in plasma of exposed workers and in lymphocyte cultures.

BACKGROUND: Heavy metals have been shown to alter the mechanism and release of lysosomal enzymes. In the present study, the activities of lysosomal glycohydrolases were determined in order to evaluate the asymptomatic toxic effects of low levels of exposure to arsenic (As) and antimony (Sb) in art glass workers. METHODS: N-acetyl-beta-D-glucosaminidase (NAG), beta-D-glucuronidase (GCR), alpha- and beta-D-galactosidase, alpha-D-glucosidase, and alpha-D-mannosidase were determined by a fluorimetric assay in the plasma of 26 art glass workers. Lymphocytes cultured in the presence of different species of As and Sb served as an in vitro model for the study of the protective action of selenium and zinc. RESULTS: No significant difference in the plasma levels of the various enzymes was detected in art glass workers or control subjects. The in vitro experiments demonstrated that secretion of lysosomal glycohydrolases was increased by Sb (225%) and decreased by As (57%) at the same concentration of elements (200 microg/L). The addition of bivalent selenium to the culture neutralized the effects of both metals, while zinc chloride did not show any protective effect. CONCLUSIONS: As for the plasma glycohydrolases, no praecox signs of toxicity related to a low concentration of As and Sb was evident in art glass workers. This may be due to the antagonistic effects demonstrated by these two metals in vitro. Their different mechanism of action on release of glycohydrolases is being discussed.

Serum cytosolic beta-glucosidase elevation and early ischemic injury to guinea pig small intestine.

BACKGROUND: The lack of an early, sensitive marker for intestinal ischemia has led to delay in diagnosis and worsended outcome for patients with acute onset of this condition. Our preliminary studies revealed that guinea pig cytosolic beta-glucosidase (CBG) is expressed predominantly in the small intestine, with lower levels in the liver and pancreas and undetectable levels in other organs. Cytosolic beta-glucosidase was investigated as a serum marker of small intestinal ischemia in a guinea pig model. METHODS: Guinea pigs underwent anesthesia, sham laparotomy, 30 minutes of mesenteric ischemia followed by 6 hours of reperfusion 6 hours of sustained mesenteric ischemia, or closed-loop small bowel obstruction. Serum samples were assayed for CBG activity. At the conclusion of the ischemia/reperfusion experiments, small bowel samples were assayed for residual enzyme activity, and paraffin sections were graded for the severity of histologic injury. RESULTS: Serum CBG activity rose rapidly after intestinal ischemia with and without reperfusion. Peak enzyme activities were elevated 23-fold for reperfused animals (P < .001) by 4 hours. For nonreperfused animals, peak serum CBG activities reached 29-fold above baseline and were significantly higher than the CBG activities of reperfused animals at 4 hours (P < .01) and at 6 hours (P < .05). Mucosal injury ranged from undetectable to moderate and corresponded in severity with both peak serum enzyme activity and decreased residual activity in the small bowel. In animals subjected to closed-loop obstruction, there was a mean increase of serum CBG of 9.2-fold from 4 to 6 hours after establishment of obstruction (P < .05). CONCLUSIONS: In the guinea pig model, CBG is a sensitive marker of ischemic injury caused by arterial occlusion or closed-loop obstruction of the small bowel.

[Gaucher's disease suspected by abdominal echography findings]. / Enfermedad de Gaucher sospechada por los hallazgos de la ecografía abdominal.

Abdominal ultrasonographic findings of Gaucher's disease had been reported, but a specific pattern has not been described. We report here a patient with an abdominal sonographic pattern which was concluded to be strongly suggestive of Gaucher's disease: solid focal splenic lesions with different patterns (hypoechoic, hiperechoic and mixed nodules associated with hypoechoic irregular areas) and bright liver and spleen echo pattern with posterior beam attenuation. Gaucher's disease was subsequently confirmed by determination of leukocyte beta-glucosidase activity and mutations of glucocerebrosidase gene.

Bone marrow transplantation in Gaucher's disease: effect of mixed chimeric state.

The effective dose and schedule of enzyme replacement therapy for Gaucher's disease have not been definitely established. We report a case of mixed chimeric state in an allogeneic BMT patient and followed her clinical and laboratory progress. The result shows that a low but sustained glucocerebrosidase level may provide symptomatic relief for this lysosomal disorder.

beta-Glucosidase activity in fetal bovine serum renders the plant glucoside, hypoxoside, cytotoxic toward B16-F10-BL-6 mouse melanoma cells.

By using p-nitrophenyl-beta-D-glucopyranoside as substrate, beta-glucosidase activity was observed in fetal bovine serum (FBS). This activity could be inhibited by heat inactivation of the serum. Gel chromatography of FBS indicated the presence of beta-glucosidase activity with an apparent molecular mass of 29 kDa. In McCoy's 5A medium supplemented with non-heat inactivated FBS, the diglucoside hypoxoside ([E]-1,5-bis[4'beta-D-glucopyranosyloxy-3'-hydroxyphenyl]pent-4-en - 1-yne) showed cytotoxicity toward B16-F10-BL-6 mouse melanoma cells. In incubations where the media were supplemented with FBS previously heat inactivated at 56 degrees C for 1 h or more, no cytotoxicity was observed in the presence of hypoxoside. The aglucone of hypoxoside, rooperol ([E]-1,5-bis[3',4'-dihydroxyphenyl]pent-4-en-1-yne), showed cytotoxicity regardless of whether the serum was heat inactivated or not. The kinetics of the heat inactivation of the beta-glucosidase activity in FBS coincided with the loss of apparent cytotoxicity of hypoxoside. High performance liquid chromatography analysis showed that rooperol could be generated by incubation of hypoxoside in non-heat inactivated FBS, but that this ability was lost in serum that was heat inactivated for 1 h or longer. Newborn bovine serum did not contain any beta-glucosidase activity whereas it was found in three different commercial sources of FBS. This observation is of practical importance because conventional heat inactivation of FBS at 56 degrees C for 30 min was not sufficient to inactivate the beta-glucosidase activity completely.

On the biocompatibility of IBM 2997 continuous flow plateletapheresis.

During the procedure of centrifugation cytapheresis donors occasionally experience adverse clinical reactions. We evaluated the possibility of whether activation of granulocytes and their subsequent release reactions, which may have been triggered by this extracorporeal circuit, were responsible for these adverse effects. Six blood samples were obtained during various set intervals during plateletapheresis. Of these, four samples were taken directly from each donor. The remaining two were drawn from the efferent lines, i.e. those which return blood from the cytapheresis machine back to the donor. Reactive oxygen species produced by granulocytes were monitored by chemiluminescence using microamounts of whole blood or isolated granulocytes. Furthermore, secreted granulocyte products such as neutral proteinase elastase, present in plasma in a complex with alpha 1-proteinase inhibitor (complexed elastase), and lysosomal beta-glucuronidase were examined. A complete blood cell count, as well as values of haemoglobin, haematocrit, lactate dehydrogenase, protein, albumin and proteinase inhibitors such as alpha 2-macroglobulin and alpha 1-proteinase inhibitor were also determined. Complexed elastase increased from a preapheresis value of about 140 micrograms/l to about 180 micrograms/l at the end of the cytapheresis. All other clinical chemical and cytological values were 8 to 12 percent lower than preapheresis values, which can be attributed to inherent plasma volume expansion. Reduced chemiluminescence was observed upon stimulation of phagocytes in the whole blood assay (about 700 counts/min x 10(3) x 50,000 cells vs. about 600 counts/min x 10(3) x 50,000 cells). This decrease was also seen with stimulated granulocytes (about 5800 counts/min x 10(3) x 50,000 cells vs. about 4500 counts/min x 10(3) x 50,000 cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Use of 4-heptylumbelliferyl-beta-D-glucoside to identify Gaucher's disease heterozygotes.

Three fluorometric beta-glucosidase assays were compared for their ability to identify Gaucher's disease heterozygotes, using leukocytes as the source of enzyme: the pH 5.5-taurocholate assay of Peters et al.; the conduritol B epoxide dependent variation of that assay; and the newly developed method described herein. While the first two procedures utilize the standard substrate 4-methylumbelliferyl-beta-D-glucopyranoside to estimate beta-glucosidase activity, the new assay uses 4-heptylumbelliferyl-beta-D-glucoside as (C7UGlc) substrate. Use of this substrate enhances the specificity of the method for lysosomal glucocerebrosidase, thereby minimizing the contribution of the nonspecific cytosolic beta-glucosidase to estimates of substrate hydrolysis. Using Student's t test for the three assays examined, the C7UGlc assay procedure was determined to have the lowest p value (p less than 0.001) and highest t value (t = 4.95) for the discrimination between the mean glucocerebrosidase value of control and obligate Gaucher heterozygote samples. The high reliability and simplicity of the C7UGlc assay lends adequate reason to favor this assay for regular clinical diagnosis of Gaucher heterozygotes.

Pseudo-Gaucher cells in the bone marrow of a patient with Hodgkin's disease.

The authors studied an 18-year-old woman with stage IIIB nodular sclerosis Hodgkin's disease whose bone marrow contained abnormal storage cells that resembled Gaucher cells by light microscopic examination ("pseudo-Gaucher" cells). Electron microscopic examination revealed that these cells differed from true Gaucher cells and resembled storage cells previously described in chronic myelogenous leukemia. The patient's peripheral blood leukocyte beta-glucosidase and serum acid phosphatase levels were elevated, ruling out the diagnosis of inherited Gaucher's disease. After treatment with six monthly cycles of systemic chemotherapy (nitrogen mustard, vincristine, procarbazine, bleomycin, doxorubicin, and prednisone), all signs of Hodgkin's disease and pseudo-Gaucher cells disappeared. Repeat leukocyte beta-glucosidase and serum acid phosphatase levels were unchanged. The present case is unique with its documentation of classical enzyme patterns for beta-glucosidase and acid phosphatase and electron microscopic features. The authors postulate that pseudo-Gaucher cells result from excessive cell breakdown with an overload of available beta-glucosidase.

Serum beta-N-acetylglucosaminidase, beta-D-glucosidase, alpha-D-glucosidase, beta-D-fucosidase, alpha-L-fucosidase and beta-D-galactosidase levels in acute viral hepatitis, pancreatitis, myocardial infarction and breast cancer.

The specific activities of several glycosidases (beta-N-acetylglucosaminidase, beta-D-glucosidase, alpha-D-glucosidase, beta-D-fucosidase, alpha-L-fucosidase and beta-D-galactosidase) were determined in human sera from a control group to 10 normal subjects and in four groups, each of 10 patients, with acute viral hepatitis, acute pancreatitis, acute myocardial infarction and breast cancer. The results show significantly higher activities in acute viral hepatitis for beta-N-acetylglucosaminidase, beta-D-glucosidase and alpha-D-glucosidase (p less than 0.001); in acute pancreatitis for the first two of these enzymes (p less than 0.001); and in breast cancer for beta-D-glucosidase (p less than 0.001). Further, lower differences were found in the patients with acute viral hepatitis for beta-D-fucosidase and alpha-L-fucosidase (p less than 0.01); in acute myocardial infarction for beta-N-acetylglucosaminidase, beta-D-glucosidase, alpha-D-glucosidase, beta-D-fucosidase and beta-D-galactosidase (p less than 0.01, p less than 0.05, p less than 0.05, p less than 0.01 and p less than 0.01, respectively); and in breast cancer for beta-N-acetylglucosaminidase (p less than 0.01). No significant differences were found for the other glycosidases.

[Glycosidases of mammals: association of activities and changes of levels in some disorders]. / Glicosidasas de m amíferos: asociación de actividades y variaciones de niveles en algunos trastornos.

beta-Galactosidase and associated activities (beta-glucosidase and beta-fucosidase) have been studied in rabbit and bovine liver and rabbit spleen. The physico-chemical (optimal pH, pI, MW) and kinetical (Km, Vmax, Ki) properties were determined for all the activities. Two enzyme forms were separated in rabbit spleen. beta-Galactosidase, beta-fucosidase and beta-glucosidase activities were catalyzed by the same enzyme in rabbit and bovine liver. The enzyme from bovine liver showed nonlinear double-reciprocal plots, suggesting a substrate-activation model, and the presence of more than one binding site in the enzyme. The enzyme activities of several glycosidases were determined in human sera fom control groups and from patients with diabetes mellitus, pancreatitis, hepatitis, cirrhosis, stomach and breast cancer, myocardial infarction and renal failure. The results show significantly different enzyme levels for several glycosidases in all the studied diseases. Experimentally-induced diabetes mellitus, alcoholism and nephrotoxicity in rats showed different glycosidase levels in several tissues, as compared with control groups.

Lymphoblastoid cell lines, transformed by Epstein-Barr virus, in the enzymatic study of hereditary lysosomal storage diseases.

Assay conditions were studied for eight lysosomal enzymes in lymphoblastoid cell lines transformed by Epstein-Barr virus. The transformed lymphoblastoid cells retained all eight enzyme activities, though the levels sometimes differed from those in the peripheral lymphocytes or granulocytes. The levels of these eight lysosomal enzymes were measured in lymphoblastoid cells from 11 patients with hereditary lysosomal storage diseases--GMI-gangliosidosis, a variant of beta-galactosidase deficiency (sialidase deficiency with a partial beta-galactosidase deficiency), Tay-Sachs disease, Gaucher disease, Hurler syndrome, Scheie syndrome and I-cell disease--and from 20 of their obligate heterozygotes. No activity of enzymes that were deficient in the respective disease, except I-cell disease, was detected in the lymphoblastoid cells from the patient. In I-cell disease, the cells showed lower levels of some enzyme activities. beta-D-Galactosidase activity from heterozygotes of the patient with GMI-gangliosidosis and alpha-L-iduronidase activity from heterozygotes of the patient with Hurler syndrome were in carrier range. On sephadex G-150 gel filtration, beta-D-galactosidase in control material gave two peaks (I and II). In GMI-gangliosidosis, peak II was absent and peak I was markedly diminished. Peak II in the heterozygotes was smaller than that of control. On DEAE cellulose column chromatography of hexosaminidase, two major isoenzymes (hexosaminidase A and B) were detected in control. However, hexosaminidase A was not detected in Tay-Sachs disease, and the ratios of hexosaminidase (Hex) A/Hex B in the parents were lower than those in control.

Acid hydrolases in sera and plasma from patients with cystic fibrosis.

The enzyme activities of alpha-fucosidase (pH 4.0 and pH 5.5), alpha-galactosidase, beta-galactosidase, alpha-glucosidase (pH 4.5 and pH 6.0), beta-glucosidase, beta-glucuronidase, beta-hexosaminidase, and alpha-mannosidase (pH 4.5 and pH 5.5) were investigated in sera from cystic fibrosis (CF) patients. Several of these activities were significantly increased in sera from patients compared to age-matched control children. CF-patients in a more advanced stage of the disease had a tendency to higher values of some of these hydrolases than those in better condition. No new isoenzymes of these hydrolases were found. Only minor differences could be detected in the pH-profiles of alpha-mannosidase and acid phosphatase from age-matched normal controls, heterozygotes and homozygotes for CF. With our technique, alpha-mannosidase and acid phosphatase showed the same thermostability in CF-patients. CF-heterozygotes and age-matched controls, except at 56 degrees C, when the activity of acid-phosphatase in the plasma from adult CF-heterozygotes decreased more than that from adult controls

Gaucher's disease. I. Modern enzymatic and anatomic methods of diagnosis.

The physician who diagnoses Gaucher's disease should take advantage of the noninvasive method that analyzes WBCs for residual beta-glucocerebrosidase and beta-glucosidase activities. When this method is carried out in conjunction with the measurement of serum acid phosphatase levels, a bone marrow examination may be unnecessary. With this method, we studied an adult who had mild splenomegaly and abdominal pain. When bone marrow was finally obtained subsequent to diagnosis by the enzymatic analysis, the deposits that are specifically formed in Gaucher's disease were easily demonstrated by electron microscopy. We believe that these methods are more specific for the diagnosis of Gaucher's disease than is the light microscopic finding of bone marrow cells that have abundant and striated cytoplasm.