Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

K562 is a human leukemic cell line used as model of hematopoietic differentiation. A variety of differentiation-inducing agents was used in this study, and the expression of surface membrane antigens associated with specific lineages of differentiation and changes in the cytochemistry of the induced cells were monitored. Sodium butyrate, hemin, retinoic acid, dimethyl sulfoxide (DMSO), phorbol myristate acetate (PMA), and interferon induced unique alterations in the binding of monoclonal antibodies specific for erythroid, granulocytic, monocytic, and megakaryocytic lineages. Hemoglobinization, Sudan Black B, glycogen content, nonspecific esterase, alkaline phosphatase, and 5'-nucleotidase staining were also altered. K562 cells were terminally differentiated with PMA to nitroblue tetrazolium-(NBT) positive macrophages. Expression of 3-fucosyl-N-acetyl lactosamine, previously thought to be myeloid specific but found on all early hematopoietic progenitors, was modulated during differentiation to nonmyeloid lineages. Lineage infidelity was noted during functional differentiation along all hematopoietic lineages. The presence of multiple lineage surface markers and cytoplasmic characteristics in leukemic cells is not indicative of lack of potential to differentiate. K562 cells cannot be compared to any normal stage of hematopoietic differentiation, but they do have the capacity to differentiate along erythroid, macrophage, and megakaryocytic lineages.
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PMID:Differentiation of K562 leukemia cells along erythroid, macrophage, and megakaryocyte lineages. 242 57

The human monocytic leukemia cell line, THP-1, is induced to differentiate into more functionally mature monocyte (macrophage)-like cells by incubation with retinoic acid at concentrations of 10nM or higher. There is no apparent morphological change accompanying this functional maturation. These induced cells show increases in nitroblue tetrazolium reduction, immunoerythrophagocytosis, hexose monophosphate shunt activity, and 5'-nucleotidase and NAD+-glycohydrolase activities. Prostaglandin E2, dibutyryl cyclic adenosine 3':5'-monophosphate, or T-lymphocyte-derived differentiation-inducing activity, all inactive or less active alone, increase the extent of differentiation of THP-1 in combination with 10nM retinoic acid. THP-1 is also induced to differentiate by 0.1nM or higher concentrations of cholera toxin. Furthermore, 24,24-difluoro-1 alpha,25-dihydroxyvitamin D3 induces less differentiation of THP-1 compared to retinoic acid. Dimethyl sulfoxide and 12-O-tetradecanoylphorbol-13-acetate show no induction of functional differentiation. THP-1 thus joins the list of leukemic myelomonocytic cell lines (e.g., the promyelocytic HL-60 and the monoblast-like U-937) that are blocked at a relatively late stage of maturation and which differentiate in response to retinoic acid.
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PMID:Induction of functional differentiation of a human monocytic leukemia cell line (THP-1) by retinoic acid and cholera toxin. 298 63

The authors elaborated and described the optimum conditions for fixation, incubation and preparation of human blood cell samples in minimum quantities for ultrastructural and ultracytochemical investigations of 5'-nucleotidase and ATPase activities. The best preservation of the blood cell ultrastructure was obtained after fixation with buffered 1% glutaraldehyde solution followed by postfixation in buffered 1% OsO4 solution. The best ultracytochemical demonstration of 5'-nucleotidase and ATPase activities was achieved after fixation in buffered 2% formaldehyde prior to cytochemical incubation. DMSO added to either fixation or incubation media was shown to damage the plasmalemma and glycocalyx structure in cell suspensions. ATPase in 5'-nucleotidase activities were revealed in plasmalemma, cytoplasmic reticulum, Golgi complex, mitochondria and in the nuclei, in particular, in the perinuclear space, nucleolus and chromatin. With respect to the localization and activity of nucleosidephosphatases, lymphocytes proved to be most heterogenic, with the enzyme activity level directly depending on the rate of ultrastructural differentiation in lymphocytes.
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PMID:[Ultracytochemical detection of nucleoside phosphatase activity in human peripheral blood cells]. 300 81

The effect of dimethylsulfoxide (DMSO) and butyrate, agents which induce differentiation of certain cancer cells, on membrane associated 5'-nucleotidase (5'-NT) of 2 human renal carcinoma cell lines (Cur and Caki) was investigated. Under a variety of conditions of agent addition, 5'-NT specific activity increased in Cur and decreased in Caki cells. This opposite response pattern was observed for assays performed on lysates at pH 9.0 and 7.4 and assays with intact cell monolayers, even under conditions of identical cellular growth inhibition. It is concluded that the cell lines responded in a fundamentally different way to the chemical agents. An increase in 5'-NT has correlated with cell maturation for a number of processes. The DMSO induced increase in Cur 5'-NT was dependent on protein synthesis.
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PMID:Effect of dimethylsulfoxide and butyrate on 5'-nucleotidase of human renal carcinoma cells. 609 92

The effects of the differentiation-inducing agents sodium butyrate (NaOBt), dimethylsulfoxide (DMSO) and mycophenolic acid (MA), on purine nucleotide metabolism, was studied in an ovarian carcinoma cell line (GZL-8). Exposure to these agents inhibited cell proliferation, but did not affect cell viability. Three hours following exposure, NaOBt and DMSO moderately decelerated purine synthesis de novo, but MA accelerated it three-fold, this being associated with a two-fold increase in the excretion of hypoxanthine and xanthine into the incubation medium. NaOBt and DMSO did not affect the cellular nucleotide content, but MA caused a 73% decrease in GTP content and about a 50% increase in the cellular content of UTP. The following alterations in cellular enzyme activity were observed 72 h following exposure: NaOBt decreased the activity of hypoxanthine-guanine phosphoribosyltransferase and increased the activity of IMP and of AMP 5'-nucleotidases, DMSO increased the activity of IMP 5'-nucleotidase, and MA increased the activity of the two nucleotidases. The results suggest that, in the carcinoma cell line studied, the differentiation process induced by NaOBt and DMSO may be associated with a general shift in the direction of purine metabolism from anabolism to catabolism, whereas that induced by MA is associated with a specific decrease in the production of GTP.
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PMID:Effects of differentiation-inducing agents on purine nucleotide metabolism in an ovarian cancer cell line. 779 96

Bacterial endotoxin (lipopolysaccharide; LPS) given to animals in large doses results in pronounced, midzonal liver injury. Exposure to smaller, non-injurious doses of LPS augments the toxicity of certain hepatotoxicants. This study was conducted to delineate the development of injury in a rat model of augmentation of aflatoxin B(1) (AFB(1)) hepatotoxicity by LPS. At large doses (i.e., > 1 mg/kg, ip), AFB(1) administration resulted in pronounced injury to the periportal regions of the liver. Male, Sprague-Dawley rats (250-350 g) were treated with 1 mg AFB(1)/kg, ip or its vehicle (0.5% DMSO/saline) and 4 h later with either E. coli LPS (7.4 x 106 EU/kg, iv) or its saline vehicle. Liver injury was assessed 6, 12, 24, 48, 72, or 96 h after AFB(1) administration. Hepatic parenchymal cell injury was evaluated as increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities in serum and from histologic examination of liver sections. Biliary tract alterations were evaluated as increased concentration of serum bile acids and activities of gamma-glutamyltransferase (GGT), alkaline phosphatase (ALP), and 5'-nucleotidase (5'-ND) in serum. At all times and for all markers, injury in rats treated with either AFB(1) or LPS alone was absent or modest. In the AFB(1)/LPS cotreated group, hepatic parenchymal cell injury was pronounced by 24 h and had returned to control values by 72 h. The injury began in the periportal region and spread midzonally with time. Furthermore, changes in serum markers indicative of biliary tract alterations were evident by 12 h and had returned to control values by 72 h. Thus, the nature of the hepatic lesions suggested that LPS potentiated the effects of AFB(1) on both parenchymal and bile duct epithelial cells.
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PMID:Bacterial lipopolysaccharide exposure augments aflatoxin B(1)-induced liver injury. 1082 77

Exposure to small, noninjurious doses of the inflammagen, bacterial endotoxin (lipopolysaccharide, LPS) augments the toxicity of certain hepatotoxicants including aflatoxin B(1) (AFB(1)). Mediators of inflammation, in particular neutrophils (PMNs), are responsible for tissue injury in a variety of animal models. This study was conducted to examine the role of PMNs in the pathogenesis of hepatic injury after AFB(1)/LPS cotreatment. Male, Sprague-Dawley rats (250-350 g) were treated with either 1 mg AFB(1)/kg, ip or its vehicle (0.5% DMSO/saline), and 4 h later with either E. coli LPS (7. 4 x 10(6) EU/kg, iv) or its saline vehicle. Over a course of 6 to 96 h after AFB(1) administration, rats were killed and livers were stained immunohistochemically for PMNs. LPS resulted in an increase in PMN accumulation in the liver that preceded the onset of liver injury. To assess if PMNs contributed to the pathogenesis, an anti-PMN antibody was administered to reduce PMN numbers in blood and liver, and injury was evaluated. Hepatic parenchymal cell injury was evaluated as increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities in serum and from histologic examination of liver sections. Biliary tract alterations were evaluated as increased concentration of serum bile acids and activities of gamma-glutamyltransferase (GGT), alkaline phosphatase (ALP), and 5'-nucleotidase (5'-ND) in serum. Neutrophil depletion protected against hepatic parenchymal cell injury caused by AFB(1)/LPS cotreatment but not against markers of biliary tract injury. This suggests that LPS augments AFB(1) hepatotoxicity through two mechanisms: one of which is PMN-dependent, and another that is not.
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PMID:Lipopolysaccharide augments aflatoxin B(1)-induced liver injury through neutrophil-dependent and -independent mechanisms. 1105 57

The expression of ENTPD1 (ecto-nucleoside triphosphate diphosphohydrolase) along the glomerular microvasculature of the kidney is downregulated in ischemic conditions, in contrast to E5NT (ecto-5'-nucleotidase), which may explain the increased tendency for intraglomerular microthrombus formation in vivo. It has been suggested that in ischemia, reactive oxygen species (ROS) affect glomerular ENTPD1, whereas E5NT seems less sensitive to oxidant stress. To test this hypothesis, a soluble ATP and ADP hydrolyzing enzyme solution (apyrase) [0.4 U/ml] or 5'-nucleotidase solution [0.33 U/ml] as well renal tissue were exposed to ROS, generated by gamma-irradiation in vitro. The enzymes diluted in distilled water or cryostat rat kidney sections were exposed to gamma-irradiation (0.037 Gy/s) for 0, 2, 5, 10, or 15 min, with or without supplementation of the ROS scavenger dimethylsulfoxide (DMSO). The enzyme activity of the samples was biochemically tested using standard methods, before and after irradiation. The reaction product of irradiated versus nonirradiated kidney sections was semiquantitatively evaluated after histochemical staining for either glomerular ENTPD1 or glomerular E5NT expression. The results show that the enzyme activity in samples of soluble apyrase was significantly decreased after irradiation. This effect was inhibited by DMSO. In contrast, 5'-nucleotidase activity showed only a limited decline of the activity curve after irradiation, which could also be restored following supplementation of DMSO. Glomerular ENTPD1 expression showed significant decrease after irradiation of kidney sections; again, this was inhibitable by DMSO. Glomerular E5NT activity was not altered by irradiation and DMSO supplementation did not affect its activity. It is concluded that soluble apyrase as well as the glomerular ENTPD1 are sensitive to oxidant stress, which may explain their downregulation in the ischemic condition in vivo. However, soluble 5'-nucleotidase and E5NT seem much less sensitive to ROS. This relative insensitivity of E5NT to oxidant injury may counteract ischemic injury by promoting local generation of adenosine in the ischemic micro-environment.
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PMID:Histochemical detection of ischemia-like alterations induced in kidney tissue in vitro--different sensitivity to oxidant stress of glomerular ENTPD1 versus E5NT. 1916 47