Phospholipase A2, a nonnegligible enzyme superfamily in gastrointestinal diseases

Biochimie ◽  
2021 ◽  
Author(s):  
Wei Wu ◽  
Wen-Xuan Li ◽  
Chun-Hong Huang
Keyword(s):  
Phospholipase A2 ◽  
Gastrointestinal Diseases ◽  
Enzyme Superfamily

Deficiency of Group VIA phospholipase A2 Primes the Cytokine Releases by Kupffer cells and Lymphocytes

2015 ◽  
Vol 53 (12) ◽  
Author(s):  
J Inhoffen ◽  
S Tuma-Kellner ◽  
W Stremmel ◽  
W Chamulitrat
Keyword(s):  
Phospholipase A2 ◽  
Kupffer Cells

Mechanism of Inhibitory Action on Platelet Activation of a Phospholipase A2 Isolated from Lachesis muta (Bushmaster) Snake Venom

1997 ◽  
Vol 78 (05) ◽  
pp. 1372-1380 ◽  
Author(s):  
André L Fuly ◽  
Olga L T Machado ◽  
Elias W Alves ◽  
Célia R Carlinis
Keyword(s):  
Platelet Aggregation ◽  
Enzymatic Activity ◽  
Phospholipase A2 ◽  
Inhibitory Activity ◽  
Thermal Inactivation ◽  
Anticoagulant Activity ◽  
Gel Filtration ◽  
Apparent Molecular Weight ◽  
Crude Venom ◽  
Lachesis Muta

SummaryCrude venom from Lachesis muta exhibited procoagulant, proteolytic and phospholipase A2 activities. A phospholipase A2, denoted LM-PLA2 was purified from L. muta venom to homogeneity, through a combination of chromatographic steps involving gel-filtration on Sephacryl S-200 HR and reverse phase chromatography on a C2/C18 column. LM-PLA2 presented a single polypeptide chain with an isoelectric point at pH 4.7 and apparent molecular weight of 17 kDa. Partial aminoacid sequence indicated a high degree of homology for LM-PLA2 with other PLA2 from different sources.LM-PLA2 displayed a potent enzymatic activity as measured by indirect hemolysis of red blood cells but it was neither lethal when injected i.p. into mice nor did it present anticoagulant activity. Furthermore, LM-PLA2 displayed a moderate inhibitory activity on the aggregation of rabbit platelets induced by low levels of ADP, thrombin and arachidonate. In contrast, platelet aggregation induced by high doses of collagen was strongly inhibited by LM-PLA2 as well as ATP-release. Treatment of the protein with p-bromophenacyl bromide or 2-mercapto-ethanol, as well as thermal inactivation studies, suggested that the platelet inhibitory effect of LM-PLA2 is dependent on its enzymatic activity. Thus, the platelet inhibitory activity of LM-PLA2 was shown to be dependent on the hydrolysis of plasma phospholipids and/or lipoproteins, most probably those rich in phosphatidylcholine. Surprisingly, lyso-phosphatidylcholine released by LM-PLA2 from plasma was shown to preferentially inhibited collagen-induced platelet aggregation, in contrast to other PLA2s, whose plasma hydrolytic products indistinctly affect platelet’s response to several agonists.

Frequency of Gastrointestinal Diseases in Patients with End-Stage Renal Disease Treated with Long Term Dialysis

2018 ◽  
Vol 2 (2) ◽  
pp. 105-112
Author(s):  
Lutfi Zylbeari ◽  
Zamira Bexheti ◽  
Gazmend Zylbeari ◽  
Ferizate Haxhirexha ◽  
Kastriot Haxhirexha
Keyword(s):  
Renal Disease ◽  
End Stage Renal Disease ◽  
Gastrointestinal Diseases ◽  
Stage Renal Disease ◽  
End Stage

Statistical analysis of distribution, dynamics and etiological structure of bovine diseases in Vologda region

2020 ◽  
pp. 3-4
Author(s):  
Oksana B. Badeeva ◽  
Keyword(s):  
Respiratory Diseases ◽  
Birth Rate ◽  
Statistical Data ◽  
Delayed Diagnosis ◽  
Specific Weight ◽  
Gastrointestinal Diseases ◽  
Vologda Region ◽  
High Incidence ◽  
Young Cattle ◽  
High Level

Statistical data of livestock for 30 years is reflected in the article. Author used the materials of the state veterinary reporting. A comparative analysis of the number, incidence and death rate of adult animals and young cattle for two five-year periods (2001-2005 and 2014-2018). the data of the analysis of veterinary statistical reports for 2018 on the specific weight of the large horned cattle and age dynamics of calves in farms of the Vologda region are shown. A significant decrease in livestock of the large horned cattle by 56.3% (from 1990 to 2018) is shown in the analysis of the data. Over the five years 2014-2018, there was a decrease in the number of the large horned cattle by 31.3%, the birth rate of calves - by 26.2%, and the incidence of calves - by 12.3% and the mortality rate decreased by 3.3%. Despite the decline in the number of livestock, in 2018 there is a high incidence of animal diseases (49.6%). The highest incidence rate was observed among calves under 10 days of age 43.3%, 31.7% - from 11 to 30 days, 15.8% - from one to three months, 6.5% - from three to six months and 2.7% - from 6 to 12 months. Of the total number of sick calves in 2018, 63.2% had gastrointestinal diseases, and death for this reason is 49.6% of the total number of victims. Respiratory diseases affect 21.8% of young animals, and death due to respiratory diseases is 18.2%. Analysis of statistical data showed that, despite the complex of veterinary and sanitary measures, the incidence and death of calves remain at a high level. This can be explained by delayed diagnosis and low therapeutic effectiveness in gastrointestinal and respiratory diseases of cattle.

Stimulation of Ca(2+)-dependent exocytosis of the sperm acrosome by cAMP acting downstream of phospholipase A2

Reproduction ◽  
2000 ◽  
pp. 57-68 ◽  
Author(s):  
J Garde ◽  
ER Roldan
Keyword(s):  
Arachidonic Acid ◽  
Phospholipase A2 ◽  
Phospholipase C ◽  
Phosphodiesterase Inhibitors ◽  
Dibutyryl Camp ◽  
Camp Phosphodiesterase ◽  
Ram Sperm ◽  
Camp Formation ◽  
Stimulation Of

Spermatozoa undergo exocytosis in response to agonists that induce Ca2+ influx and, in turn, activation of phosphoinositidase C, phospholipase C, phospholipase A2, and cAMP formation. Since the role of cAMP downstream of Ca2+ influx is unknown, this study investigated whether cAMP modulates phospholipase C or phospholipase A2 using a ram sperm model stimulated with A23187 and Ca2+. Exposure to dibutyryl-cAMP, phosphodiesterase inhibitors or forskolin resulted in enhancement of exocytosis. However, the effect was not due to stimulation of phospholipase C or phospholipase A2: in spermatozoa prelabelled with [3H]palmitic acid or [14C]arachidonic acid, these reagents did not enhance [3H]diacylglycerol formation or [14C]arachidonic acid release. Spermatozoa were treated with the phospholipase A2 inhibitor aristolochic acid, and dibutyryl-cAMP to test whether cAMP acts downstream of phospholipase A2. Under these conditions, exocytosis did not occur in response to A23187 and Ca2+. However, inclusion of dibutyryl-cAMP and the phospholipase A2 metabolite lysophosphatidylcholine did result in exocytosis (at an extent similar to that seen when cells were treated with A23187/Ca2+ and without the inhibitor). Inclusion of lysophosphatidylcholine alone, without dibutyryl-cAMP, enhanced exocytosis to a lesser extent, demonstrating that cAMP requires a phospholipase A2 metabolite to stimulate the final stages of exocytosis. These results indicate that cAMP may act downstream of phospholipase A2, exerting a regulatory role in the exocytosis triggered by physiological agonists.

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