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The edema inducing activity of phospholipase A2 enzymes

Tan NH, Saifuddin MN, Yong WY

Biochem. Int., 1991 Jan;23(1):175-81.
PMID: 1863271

The edema inducing activity of phospholipase A2 (PLA2) enzymes from snake venoms and porcine pancreas was investigated using mouse paw as experimental model. All ten PLA2 enzymes exhibited potent edema inducing activity. PLA2, however, is generally not the major edema inducing component of snake venom. Chemical modification studies indicated that enzymatic activity of PLA2 was required for its edema inducing activity. All PLA2 enzymes examined displayed a rapid onset edema which was suppressed by pretreatment of the mice with antihistamine. Dexamethasone pretreatment also inhibited edemas elicited by some PLA2 enzymes.

Matched MeSH terms: Phospholipases A2
Oxidative stress and sperm function: A systematic review on evaluation and management

Dutta S, Majzoub A, Agarwal A

Arab J Urol, 2019;17(2):87-97.
PMID: 31285919 DOI: 10.1080/2090598X.2019.1599624

Objective: To review and present the most distinct concepts on the association of reactive oxygen species (ROS) with male reproduction. Methods: The Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) guidelines were used to search PubMed, Medline, EMBASE, and the Cochrane electronic databases for studies investigating the role of oxidative stress (OS) on sperm function. Results: The literature search yielded 1857 studies, of which 1791 articles were excluded because of irrelevance of data, non-English language, non-human nature or because they were case reports or commentaries. All included studies were reviews (46), meta-analyses (one), original research studies (18) and guideline articles (one). The studies were published between 1984 and 2018. Under normal physiological conditions, ROS are vital for sperm maturation, hyperactivation, capacitation, acrosome reaction, as well as fertilisation. However, a number of endogenous and exogenous causes may induce supra-physiological levels of ROS resulting in lipid peroxidation, sperm DNA fragmentation and apoptosis, and consequently infertility. Several laboratory testing methods can be used in infertile men to diagnose OS. Treatment usually involves antioxidant supplementation and, when possible, elimination of the causative factor. Conclusion: OS is an important cause of male factor infertility. Its assessment provides essential information that can guide treatment strategies aimed at improving the male's reproductive potential. Abbreviations: bp: base-pair; CAT: catalase; LPO: lipid peroxidation; MDA: malondialdehyde; MiOXSYS: Male Infertility Oxidative System; mtDNA: mitochondrial DNA; NAD(PH): nicotinamide adenine dinucleotide (phosphate); NO: nitric oxide; 8-OHdG: 8-hydroxy-2'-deoxyguanosine; ORP: oxidation-reduction potential; OS: oxidative stress; PKA: protein kinase A; PLA2: phospholipase A2; PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses; PUFA: poly-unsaturated fatty acid; ROS: reactive oxygen species; SOD: superoxide dismutase; TAC: total antioxidant capacity; TBA: thiobarbituric acid.

Matched MeSH terms: Phospholipases A2
Two-dimensional polyacrylamide gel electrophoresis of Bali bull (Bos javanicus) seminal plasma proteins and their relationship with semen quality

Sarsaifi K, Haron AW, Vejayan J, Yusoff R, Hani H, Omar MA, et al.

Theriogenology, 2015 Oct 1;84(6):956-68.
PMID: 26119476 DOI: 10.1016/j.theriogenology.2015.05.035

The present study evaluated the relationship between Bali bull (Bos javanicus) seminal plasma proteins and different semen quality parameters. Semen samples from 10 mature Bali bulls were evaluated for conventional semen parameters (general motility, viability, and normal morphology), sperm functionality (acrosome reaction, sperm penetration rate, sperm penetration index), sperm kinetics (computer-assisted semen analysis parameters such as sperm velocity), and sperm morphology (acrosome and membrane integrity). Frozen-thawed semen with higher sperm motility, viability, acrosome integrity, and membrane integrity (P < 0.05) are consistently higher in acrosome reaction and sperm penetration assay. Three bulls showed the highest, four bulls displayed the medium, and the remaining three bulls showed the lowest for all sperm parameters and SPA. The proteome maps of seminal plasma from high-quality and low-quality Bali bulls were also established. Seminal plasma of both high-quality and low-quality Bali bulls was subjected to two-dimensional SDS-PAGE with isoelectric point ranged from 3 to 10 and molecular weight from 10 to 250 kDa. Approximately 116 spots were detected with Blue Silver stain, and of these spots, 29 were selected and identified by MALDI-TOF/TOF-MS/MS. A majority of the proteins visualized in the seminal plasma two-dimensional maps was successfully identified. An essential group of the identified spots represented binder of sperm 1 (BSP1), clusterin, spermadhesin, tissue inhibitor of metalloproteinases 2 (TIMP-2), and phospholipase A2 (PLA2). Other proteins found in high abundance included seminal ribonuclease, serum albumin, cationic trypsin, and peptide similar to β2 microglobulin. Thus, a reference map of Bali bull seminal plasma proteins has been generated for the very first time and can be used to relate protein pattern changes to physiopathologic events that may influence Bali bull reproductive performance.

Matched MeSH terms: Phospholipases A2
Induction of cell death and modulation of Annexin A1 by phytoestrogens in human leukemic cell lines

Sabran A, Kumolosasi E, Jantan I, Jamal JA, Azmi N, Jasamai M

Saudi Pharm J, 2021 Jan;29(1):73-84.
PMID: 33603542 DOI: 10.1016/j.jsps.2020.12.011

Background: Phytoestrogens are polyphenolic plant compounds which are structurally similar to the endogenous mammalian estrogen, 17β-estradiol. Annexin A1 (ANXA1) is an endogenous protein which inhibits cyclo-oxygenase 2 (COX-2) and phospholipase A2, signal transduction, DNA replication, cell transformation, and mediation of apoptosis.
Objective: This study aimed to determine the effects of selected phytoestrogens on annexin A1 (ANXA1) expression, mode of cell death and cell cycle arrest in different human leukemic cell lines.
Methods: Cells viability were examined by MTT assay and ANXA1 quantification via Enzyme-linked Immunosorbent Assay. Cell cycle and apoptosis were examined by flow cytometer and phagocytosis effect was evaluated using haematoxylin-eosin staining.
Results: Coumestrol significantly (p

Matched MeSH terms: Phospholipases A2
Regional and accelerated molecular evolution in group I snake venom gland phospholipase A2 isozymes

Chuman Y, Nobuhisa I, Ogawa T, Deshimaru M, Chijiwa T, Tan NH, et al.

Toxicon, 2000 Mar;38(3):449-62.
PMID: 10669032

In accordance with detection of a few phospholipase A2 (PLA2) isozyme genes by Southern blot analysis, only two cDNAs, named NnkPLA-I , and NnkPLA-II, encoding group I PLA2s, NnkPLA-I and NnkPLA-II, respectively, were isolated from the venom gland cDNA library of Elapinae Naja naja kaouthia of Malaysia. NnkPLA-I and NnkPLA-II showed four amino acid substitutions, all of which were brought about by single nucleotide substitution. No existence of clones encoding CM-II and CM-III, PLA2 isozymes which had been isolated from the venom of N. naja kaouthia of Thailand, in Malaysian N. naja kaouthia venom gland cDNA library was verified by dot blot hybridization analysis with particular probes. NnkPLA-I and NnkPLA-II differed from CM-II and CM-III with four and two amino acid substitutions, respectively, suggesting that their molecular evolution is regional. The comparison of NnkPLA-I, NnkPLA-II and cDNAs encoding other group I snake venom gland PLA2s indicated that the 5'- and 3'-untranslated regions are more conserved than the mature protein-coding region and that the number of nucleotide substitutions per nonsynonymous site is almost equal to that per synonymous site in the protein-coding region, suggesting that accelerated evolution has occurred in group I venom gland PLA2s possibly to acquire new physiological functions.

Matched MeSH terms: Phospholipases A2
Isolation and characterization of the major phospholipase A2 from the venom of Trimeresurus purpureomaculatus (shore pit viper)

Nget Hong Tan, Chon Seng Tan, Hun Teck Khor

Int. J. Biochem., 1989;21(12):1421-6.
PMID: 2612728

1. The major phospholipase A2 (PLA-DE4) of the venom of Trimeresurus purpureomaculatus (shore pit viper) has been purified to electrophoretic homogeneity. 2. The isoelectric point of the purified enzyme was determined to be 4.20, and the mol. wt was 31,700 as estimated by Sephadex G-75 gel filtration chromatography; and 14,000 as estimated by SDS-polyacrylamide gel electrophoresis. The purified enzyme hydrolyzed phosphatidylcholine (PC) faster than phosphatidylethanolamine (PE), whereas phosphatidylserine (PS) was not hydrolyzed at all (PC greater than PE greater than PS =0). However, in reaction system consisted of mixtures of PC and PS, phosphatidylserine was effectively hydrolyzed by the enzyme. 4. The phospholipase A2 exhibited edema-forming activity but not hemolytic, hemorrhagic or anticoagulant activities. It was not lethal to mice at a dosage of 10 micrograms/g by i.v. route.

Matched MeSH terms: Phospholipases A2
Neuromuscular effects of four phospholipases A2 from the venom of Pseudechis australis, the Australian king brown snake

Geh SL, Rowan EG, Harvey AL

Toxicon, 1992 Sep;30(9):1051-7.
PMID: 1440642

Four homologous single chain phospholipases A2 (Pa-1G, Pa-5, Pa-12C and Pa-15) were tested for neuromuscular effects on chick biventer cervicis and mouse hemidiaphragm nerve-muscle preparations. The four isozymes blocked directly elicited (mouse hemidiaphragm) and indirectly elicited (mouse and chick nerve-muscle preparations) twitch responses in concentrations of 1-30 micrograms/ml. The order of potency seen in both types of preparations was Pa-1G = Pa-5 greater than Pa-12C much greater than Pa-15. All four isozymes caused slow-onset, sustained contractures and reduction of muscle membrane potentials. In the chick preparation, responses to acetylcholine, carbachol and KCl were reduced by exposure to the toxins. It is concluded that the toxins act primarily postsynaptically to depress muscle contractility, perhaps by directly damaging muscle fibres. The order of potency agrees with their phospholipase A2 activity. Pa-1G is unusual because it is an acidic molecule, most toxic phospholipases being basic.

Matched MeSH terms: Phospholipases A2
Cloning and characterization of cDNAs encoding three isoforms of phospholipase A2 in Malayan spitting cobra (Naja naja sputatrix) venom

Armugam A, Earnest L, Chung MC, Gopalakrishnakone P, Tan CH, Tan NH, et al.

Toxicon, 1997 Jan;35(1):27-37.
PMID: 9028006

cDNAs encoding three phospholipase A2 (PLA2) isoforms in Naja naja sputatrix were cloned and characterized. One of them encoded an acidic PLA2 (APLA) while the others encoded neutral PLA2 (NPLA-1 and NPLA-2). The specific characteristics of APLA and NPLA were attributed to mutations at nt139 and nt328 from G to C and G to A, respectively, resulting in amino acid substitutions from Asp20 and 83 in APLA to His20 and Asn83 in NPLA. Amino acid sequencing of purified protein also showed the presence of this Asp20 and His20 in APLA and NPLA, respectively. The cDNA encoding one of the PLA2 (NAJPLA-2A), when expressed in Escherichia coli, yielded a protein that exhibited PLA2 activity.

Matched MeSH terms: Phospholipases A2