Levels Of Beta-hexosaminidase Research Articles

TBBPA regulates calcium-mediated lysosomal exocytosis and thereby promotes invasion and migration in hepatocellular carcinoma.

Tetrabromobisphenol A (TBBPA) and its derivatives are the common flame-retardants that may increase the risk of development of many types of cancers, including liver cancer. However, the effects of TBBPA in the development and progression of liver cancer remains unknown. This study investigated the potential effects of TBBPA on a metastatic phenotype of hepatocellular carcinoma cell line-HepG2. Our results revealed that TBBPA significantly promoted the migration and invasion via affecting the number and distribution of lysosomes in HepG2 cells in a dose-dependent manner. Moreover, TBBPA decreased the intracellular protein levels of Beta-Hexosaminidase (HEXB), Cathepsin B (CTSB) and Cathepsin D (CTSD) while increased the extracellular CTSB and CTSD. It entailed that TBBPA exposure could promote the lysosomal exocytosis in cancer cells. The reversal results were obtained after adding lysosomal exocytosis inhibitor vacuolin-1. Docking results suggested that TBBPA could bind to TRPML1. It was consistent with the binding position of agonist ML-SA1. TRPML1 knockdown significantly decreased the invasion and migration, and the results were reversed when TBBPA was added. The results were indicated that TRPML1 was critical in lysosomal exocytosis. In addition, our results showed that TBBPA-TRPML1 complex regulated the calcium-mediated lysosomal exocytosis, thereby promoting the metastasis in liver cancer cells. It was expected that our data could provide important basis for understanding the molecular mechanism(s) of TBBPA promoting invasion and migration of hepatoma cells and give rise to profound concerns of TBBPA exposure on human health.

A rare case of Sandhoff disease: two in the same family

Sandhoff disease is a rare lysosomal storage disorder which is inherited in an autosomal recessive pattern. Prevalence of Sandhoff disease is 1 in 384000 live births. Here we report a 14 month old male child who presented with macrocephaly, regression of developmental milestones and seizures. Fundus examination showed macular cherry red spot. Enzyme studies revealed reduced levels of beta hexosaminidase A and B, following which a diagnosis of Sandhoff disease was made. Mother was offered prenatal diagnosis of the fetus in the subsequent pregnancy, which was also found to have the same enzyme deficiency and the pregnancy was medically terminated. Early identification of this neurodegenerative disorder, helped in preventing the birth of subsequent affected children in the same family, thereby reducing the burden on the family as well as the society.

Nasal allergen deposition leads to conjunctival mast cell degranulation in allergic rhinoconjunctivitis.

The naso-ocular interaction in allergic rhinoconjunctivitis is well recognized from epidemiological, clinical, and experimental observations. The precise mechanisms remain incompletely understood. A new mouse model of allergic rhinoconjunctivitis was used to investigate the contribution of mast cells and trigeminal ganglia activation to conjunctival (conj.) inflammation after nasal allergen provocation. Sensitized mice were exposed to ovalbumin (OVA) via the nose and/or conjunctiva, and conj. homogenates were analyzed for histamine and substance P (using ELISA) and by eosinophil peroxidase (EPO) and beta-hexosaminidase assays. The conj. effects of nasal allergen deposition were compared with those induced by the mast cell activator C48/80 and with pretreatment of the mast cell stabilizer ketotifen or the transient receptor potential channel receptor (TRP) agonist capsaicin. Protachykinin 1 (TAC1) expression was quantified in the trigeminal ganglia using real time polymerase chain reaction. At 1 hour after nasal application of OVA, increased conj. levels of beta-hexosaminidase (0.68 ± 0.03 nm versus 0.56 ± 0.02 nm; p = 0.02), histamine (751.1 ± 52.17 ng/mL versus 546.3 ± 76.91 ng/mL; p = 0.05), and EPO (0.66 ± 0.09 nm versus 0.37 ± 0.03 nm; p = 0.02) were detected compared with saline. Higher levels of TAC1 expression were found in the trigeminal ganglia at 24 hours after OVA application (1326 ± 255 versus 687.5 ± 90.77 TAC1/beta-actin; p = 0.04). Nasal challenge with C48/80 increased substance P and beta-hexosaminidase levels in the conjunctiva, as well as TAC1 expression. Pretreatment with ketotifen resulted in lower levels of substance P as well as TAC1 expression. Destruction of sensory nerves in the nose by capsaicin reduced the OVA-induced conj. levels of substance P, histamine, and beta-hexosaminidase. Nasal allergen deposition in sensitized mice induced trigeminal TAC1 expression and conj. mast cell degranulation. These data represent a significant step forward in understanding the close interaction between nasal and conj. inflammation in allergy.

Effect of modified-Okbyungpoongsan on mast cell-mediated allergic responses in RBL-2H3 mast cells

Objectives : In this study, we investigated the effect of modified-Okbyungpoongsan (mOP) on mast cell-mediated allergic response in basophilic leukemia cell line, RBL-2H3 mast cells. Methods : Cells were stimulated with anti-DNP-IgE after the treatment of DNP-HSA (AI/D), and then incubated with different concentrations of mOP (0.1, 0.2, 0.5 and 1 mg/) in RBL-2H3 cells. Cell toxicity was determined by WST-1 assay. The degranulation of mast cells was observed by microscope with toluidine blue staining and also the levels of beta-hexosaminidase, histamine and TNF-alpha were measured in culture supernatants by enzyme-linked immunosorbant assay. Results : mOP inhibited anti-DNP-IgE-imduced degranulation of mast cells in RBL-2H3 cells. mOP also significantly decreased the levels of histamine and inflammatory cytokine, TNF-alpha in RBL-2H3 cells, but slightly decreased the level of beta-hexosaminidase. Conclusions : These results indicate that mOP, an oriental prescription could be inhibit the allergic response through suppressing the mast cell activation.

Stem cells act through multiple mechanisms to benefit mice with neurodegenerative metabolic disease

Intracranial transplantation of neural stem cells (NSCs) delayed disease onset, preserved motor function, reduced pathology and prolonged survival in a mouse model of Sandhoff disease, a lethal gangliosidosis. Although donor-derived neurons were electrophysiologically active within chimeric regions, the small degree of neuronal replacement alone could not account for the improvement. NSCs also increased brain beta-hexosaminidase levels, reduced ganglioside storage and diminished activated microgliosis. Additionally, when oral glycosphingolipid biosynthesis inhibitors (beta-hexosaminidase substrate inhibitors) were combined with NSC transplantation, substantial synergy resulted. Efficacy extended to human NSCs, both to those isolated directly from the central nervous system (CNS) and to those derived secondarily from embryonic stem cells. Appreciating that NSCs exhibit a broad repertoire of potentially therapeutic actions, of which neuronal replacement is but one, may help in formulating rational multimodal strategies for the treatment of neurodegenerative diseases.

Effects of triton WR 1339 and orotic acid on biliary and serum dolichols in rats

Two lysosomal storage diseases, aspartylglucosaminuria and mannosidosis, are associated with highly elevated serum dolichol concentrations. To elucidate possible mechanisms leading to elevated serum dolichols, we studied the effects of Triton WR 1339 (known to increase serum cholesterol) and orotic acid (known to decrease serum cholesterol) on blood and biliary dolichol and beta-hexosaminidase levels in rats. In Triton WR 1339-treated rats, serum dolichol was markedly increased compared with saline-treated controls 1 (400 +/- 70 ng/mL, n = 7 v 85 +/- 11 ng/mL, n = 8, P < .001), 4 (789 +/- 70 ng/mL, n = 10 v 110 +/- 10 ng/mL, n = 7, P < .0001), and 8 (549 +/- 43 ng/mL, n = 8 v 87 +/- 8 ng/mL, n = 7, P < .001) days after administration of the drug. By contrast, serum dolichol was decreased (64 +/- 5 ng/mL, n = 8 v 119 +/- 7 ng/mL, n = 8, P < .0001) after a 7-day orotic acid feeding compared with controls. Serum beta-hexosaminidase was unaffected by both treatments. Orotic acid also increased biliary dolichol (280 +/- 47 ng/100 g body weight [BW]/h, n = 7 v 83 +/- 15 ng/100 g BW/h, n = 7, P < .01) and beta-hexosaminidase (21 +/- 3 mU/100 g BW/h, n = 7 v 8.3 +/- 2 mU/100 g BW/h, n = 9, P < .01) excretion compared with controls. Thus, both Triton WR 1339 and orotic acid have an effect on dolichol metabolism, and it is conceivable--based on our results--that serum dolichol concentrations are regulated, at least in part, by a mechanism similar to that for serum cholesterol levels.

Plasma lysosomal enzyme levels in patients with motor neuron disease

beta-Hexosaminidase and acid-alpha-mannosidase were estimated in 17 adult patients with motor neuron disease. Normal plasma levels of beta-hexosaminidase ((A+B) and A) were found in all patients studied. Plasma acid alpha-mannosidase levels were normal in all but two patients with the spinal muscular atrophy type of the disorder. In addition, altered biochemical properties of acid alpha-mannosidase (i.e. Km, thermal stability) were found in the low-activity cases.

Serum Hexosaminidase as a Possible Biomarker for Human Cancer

The levels of total serum hexosaminidase and of its heat stable isozyme (beta-hexosaminidase) were determined in the sera of subjects bearing ovarian and other female genital cancers and of control subjects. The assays were carried out on a double blind basis. Total hexosaminidase levels were significantly elevated in sera of subjects with female genital cancers and in subjects with ovarian cancer. Levels of beta-hexosaminidase were elevated in all subjects with genital cancer. The hexosaminidase assay may be a convenient biomarker for human cancer since earlier studies have shown that total and beta-hexosaminidase levels are elevated in sera of most cancer patients studied.

Carcinoembryogenic antigen and lysosomal enzymes in gastric juice as an aid in the diagnosis of gastric cancer.

Malignant transformation in cells is accompanied by enzymatic changes that may be useful markers of malignancy. Studies of oncofetal antigens in gastric juice show an increased concentration in patients with gastric carcinoma. The object of the present study was to test if the concentration of lysosomal enzymes and carcinoembryonic antigen (CEA) were altered in patients with gastric carcinoma compared to patients earlier operated with gastric resection--a supposedly premalignant condition. The results show that no differences could be found in CEA and beta-hexosaminidase levels between the patients with gastric carcinoma and those with gastric resection. However, lysozyme content was significantly higher in gastric carcinoma and might prove useful for screening of patients after gastric resection. Both CEA, beta-hexosaminidase, and lysozyme levels were significantly higher in patients with gastric carcinoma than in a control population, and can therefore have a role in screening of asymptomatic patients.

β-Hexosaminidase Level in Serum from Patients with Viral Hepatitis as a Measure of Reticuloendothelial Function

The lysosomal enzyme beta-hexosaminidase was elevated in different forms of hepatitis. The enzyme level was correlated to the aminotransferases in the acute stage of hepatitis A and B. In hepatitis B there was also a correlation to ALP and bilirubin. In chronic hepatitis B a significant correlation was found only to ALAT. The elevated beta-hexosaminidase levels are attributed to defective non-parenchymal liver cell function in hepatitis.

Secretion of lysosomal enzymes by human placental villi in vitro.

Chorionic villi from first trimester and term human placentas have been incubated in vitro and shown to release the lysosomal enzymes, beta-hexosaminidase, alpha-glucosidase and beta-glucuronidase. There was negligible release of the cytoplasmic enzyme, lactate dehydrogenase, under the same conditions. The first trimester villi released proportionally more of their lysosomal enzyme content than did the term villi. Extracellular levels of beta-hexosaminidase were raised and those of alpha-glucosidase and beta-glucuronidase were lowered when tissue was incubated with 1 microM colchicine, suggesting that microtubules are involved in the control of lysosomal enzyme release from placental villi.