Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Growth factors and their mechanisms of action have been studied extensively. However, it remained widely unrecognized that binding of ATP to growth factors is a prerequisite for their bioactivity. Here we demonstrated the binding of ATP to nerve growth factor (NGF) as well as its relevance for neuroprotection. By using mass spectrometry-based methodology we identified one or two molecules of ATP as being bound to NGF. To test neuroprotective activity of NGF we used primary cultures of rat cortical neurons damaged by staurosporine. ATP was indispensable for the neuroprotective effect of NGF. When the ATP concentration in the culture medium was reduced below approximately 2 nM by adding alkaline phosphatase (AP) or ATPase the neuroprotective activity of NGF was abolished. Site-directed mutagenesis within the heparin-binding domain (HBD) of NGF abolished ATP-binding and the neuroprotective effect. Thus, NGF has to bind ATP to be capable of protecting neurons.
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PMID:Binding of ATP to nerve growth factor: characterization and relevance for bioactivity. 1989 1

We have shown previously that nerve growth factor (NGF) requires only low nanomolar ATP concentrations in the cell culture medium to protect cortical rat neurons (CRN) from cellular damage induced by staurosporine (STS). We have also demonstrated before that NGF and other growth factors form stable non-covalent complexes with ATP. Here we demonstrated that 8N(1)ATP-NGF, but not NGF, protected CRN against damage. The photo-reactive ATP derivative 8N(3)ATP was incubated with NGF and was trapped in its position by UV irradiation forming a covalent bond. The cross-link with a molar ratio of 1:1 (8N(1)ATP:NGF) was confirmed by mass spectrometry. Circular dichroism experiments revealed that 8N(1)ATP altered the secondary structure of NGF in the same way as ATP did. Covalently bound 8N(1)ATP-NGF was shown to be stable in the presence of the ATP-hydrolyzing enzyme alkaline phosphatase while the non-covalent ATP-NGF-complex dissociated with the removal of free ATP from the solution. 8N(1)ATP-NGF protected CRN against damage by STS independently of free ATP in the culture medium. These results suggest that the ATP-NGF-complex, but not NGF, is the active ligand.
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PMID:ATP-NGF-complex, but not NGF, is the neuroprotective ligand. 2193 Jan 74

Red Liriope platyphylla (RLP) produced by steaming process has been reported to enhance the secretion of insulin and nerve growth factor (NGF). However, there has been no report on the toxicity of RLP in the specific organs of mice. To investigate the toxic effect of RLP, we tried to observe a significant alteration on body weight, food/water intake, organ weight, liver pathology and kidney pathology in female ICR mice received 12.5, 25.0 and 50.0 mg/kg body weight/day of RLP via gavage for 10 days. Out of seven organs including brain, heart, lung, liver, kidney, spleen and ovary, two organs (heart and lung) showed significantly decreased weights in the medium dosage RLP-treated group, whereas weights of other organs were maintained at constant levels in all dosage groups. In the liver toxicity analysis, no significant increase of alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate amino-transferase (AST) were detected in any RLP-treated group compared to vehicle-treated group. The specific pathological changes induced by most of toxic compounds were not observed in the liver in microscopic examination. Furthermore, in the kidney toxicological analysis, a significant enhancement of the blood urea nitrogen (BUN) concentration was detected in the high dosage RLP-treated group compared to the vehicle-treated group. However, the serum creatinine (CA) concentration on the serum biochemistry as well as the pathological changes in microscopic examination were not significantly different between the vehicle- and RLP-treated groups. Therefore, these results suggest that RLP does not induce any specific toxicity in liver or kidney tissues of mice, although the BUN level slightly increased in 50.0 mg/kg of RLP-treated group.
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PMID:Toxicity of red Liriope platyphylla manufactured by steaming process on liver and kidney organs of ICR mice. 2332 83

The isolation and characterization of individual snake venom components is important for a deeper understanding of the pathophysiology of envenomations, for improving the therapeutic procedures of patients, and it also opens possibilities for the discovery of novel toxins that might be useful as tools for understanding cellular and molecular processes. This review provides a summary of the different toxins that have been isolated and characterized from the venoms of Vipera lebetina (Macrovipera lebetina) subspecies Macrovipera lebetina cernovi, Macrovipera lebetina lebetina, Macrovipera lebetina obtusa, Macrovipera lebetina transmediterranea, Macrovipera lebetina turanica, the snake species causing the majority of human envenomings in Central Asia (Middle East) and North Africa. The venoms of these snakes contain proteins belonging to different families: Zn2+- metalloproteinases, serine proteinases, L-amino acid oxidase, 5'-nucleotidase, phosphodiesterase, phosphomonoesterase, nucleases, hyaluronidase, phospholipase A2, C-type lectin-like protein, disintegrin, DC-fragment, cystein-rich secretory protein, proteinase inhibitors, nerve growth factor (NGF), vascular endothelial growth factor (VEGF), low molecular weight peptides. Their main biochemical properties, toxic and pharmacological actions have been described. In this review we will provide an overview of the proteins and peptides from the venoms of M. lebetina subspecies, their biochemical, pharmacological and structural features and their role in snake venom toxinology. A lot of contributions have been made for better understandings of these venomous snakes, their venom, and their pharmacological effects. Many of these components are also fascinating models for drug design.
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PMID:Biochemistry and pharmacology of proteins and peptides purified from the venoms of the snakes Macrovipera lebetina subspecies. 3047 10


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