Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Gene/Protein
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Target Concepts:
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Query: UNIPROT:P00750 (
PLA
)
16,800
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Activated phagocytes, particularly polymorphonuclear leukocytes (neutrophils), by means of oxidative photonic burst, i.e., the combined activation of NADPH-oxidase and myeloperoxidase, generate large amounts of oxidants of the
hypochlorite
/chloramine type that are an important physiologic source for the nonradical, photon-emitting oxidant singlet oxygen (1O2), which (in the dark blood stream) is both a signal and an agent of defense against bacteria or fibrin. 1O2-oxidized fibrinogen or oxidized fibrin monomer has previously been shown to be unpolymerizable, and methionine to methionine sulfoxide-oxidized fibrinogen occurs in circulating blood. The present study demonstrates that thrombin converts oxidized fibrinogen into a soluble stimulator of
tissue-type plasminogen activator
(t-PA). After addition of 0.1 IU thrombin to 25 microl oxidized normal human plasma and an incubation time of 10 min (room temperature), t-PA activity increases about 20-fold when compared with oxidized plasma without the addition of thrombin. Thus, since oxidized fibrin monomer is a t-PA cofactor, thrombin-degraded oxidized fibrinogen can be used as a stimulator in functional t-PA assays.
...
PMID:Thrombin converts singlet oxygen (1O2)-oxidized fibrinogen into a soluble t-PA cofactor. A new method for preparing a stimulator for functional t-PA assays. 1140 Oct 83
Activated polymorphonuclear neutrophils (PMN) participate in physiologic thrombolysis. PMN produce large amounts of urokinase (u-PA) and oxidants of the
hypochlorite
/chloramine-type that generate nonradical excited singlet oxygen ((1)O(2)). The u-PA/(1)O(2)-mediated thrombolysis was imitated in vitro. One hundred microliters microclots of normal human plasma were oxidized with 25 microL 0 to 5.0 micromoles of chloramine-T in physiol. NaCl in the absence or presence of 100 microL 6% bovine serum albumin or 100 microL normal plasma. Twenty-five microliters 0 to 167 IU/mL (related to 150 microL added supernatant) u-PA or 0 to 2.08 microg/mL
t-PA
were added. The absorbance at 405 nm was determined after 0 to 27 hours (37 degrees C). The specific clot turbidity was calculated, subtracting the 100% lysis absorbance from the respective measured absorbance. The chloramine-effective dose 50% (ED(50)) after 27 hours was determined in the presence of 2.6 IU/mL u-PA. The
plasminogen activator
-ED(25) was determined after 2 hours (37 degrees C), and the ET(25); i.e., the time needed to lyse a microclot by 25%, was determined for each respective clot-oxidation. The ED(25) of u-PA depends on the oxidation of the microclots: 1.25 micromoles chloramine/100 microL clot enhances thrombolysis approximately 20-fold; here, 25% of clot lysis is achieved within 50 minutes (using approximately 20 IU/mL u-PA), whereas approximately 5 hours are needed to lyse an unoxidized microclot by 25%. The present global assay technique imitates the u-PA/(1)O(2) aspects of physiologic thrombolysis by PMN.
...
PMID:Singlet oxygen potentiates thrombolysis. 1763 88
Polyunsaturated fatty acids usually undergo lipid peroxidation induced by reactive oxygen species (ROS). Calcium-independent cellular phospholipase A
2
(iPLA
2
) can maintain fatty acid compositions in phospholipids depending on physiological conditions. An insect iPLA
2
(Pi-iPLA
2
) was predicted from the transciptome of the Indianmeal moth, Plodia interpunctella. It encodes 835 amino acids. It possesses five ankyrin repeats in the N terminal and patatin lipase domain in the C terminal. Pi-iPLA
2
was expressed in all developmental stages of the Indianmeal moth. In the larval stage, it was expressed in all tissues tested. RNA interference (RNAi) specific to Pi-iPLA
2
was performed using specific double-stranded RNA (dsRNA). It resulted in almost 70% of reduction in gene expression. Under such RNAi condition, P. interpunctella exhibited significant accumulation of lipid peroxidation based on the amount of malondialdehyde. RNAi of Pi-
PLA
2
expression also impaired cellular immune response of P. interpunctella. Chlorine dioxide (
ClO
2
), an insecticidal agent by generating ROS, increased lipid peroxidation in a dose-dependent manner. However, the addition of vitamin E (an antioxidant) reduced the formation of lipid peroxidation.
ClO
2
treatment significantly reduced expression of Pi-iPLA
2
but increased lipid peroxidation in larval fat body of P. interpunctella. Furthermore, larvae treated with dsRNA specific to Pi-iPLA
2
were significantly susceptible to
ClO
2
treatment. These results suggest that Pi-iPLA
2
plays a crucial role in repairing damaged fatty acids from phospholipids. Our results also suggest that
ClO
2
can elevate lipid peroxidation through inhibiting Pi-iPLA
2
expression in addition to direct ROS production.
...
PMID:Chlorine dioxide enhances lipid peroxidation through inhibiting calcium-independent cellular PLA
2
in larvae of the Indianmeal moth, Plodia interpunctella. 2918 10
