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  1. New pyrimidine-benzoxazole/benzimidazole hybrids: Synthesis, antioxidant, cytotoxic activity, in vitro cyclooxygenase and phospholipase A2-V inhibition
    Abdelgawad MA, Bakr RB, Ahmad W, Al-Sanea MM, Elshemy HAH
    Bioorg Chem, 2019 11;92:103218.
    PMID: 31536956 DOI: 10.1016/j.bioorg.2019.103218
    To enhance the cytotoxicity of benzimidazole and/or benzoxazole core, the benzimidazole/benzoxazole azo-pyrimidine were synthesized through diazo-coupling of 3-aminophenybenzimidazole (6a) or 3-aminophenylbenzoxazole (6b) with diethyl malonate. The new azo-molanates 6a&b mixed with urea in sodium ethoxide to afford the benzimidazolo/benzoxazolopyrimidine 7a&b. The structure elucidation of new synthesized targets was proved using spectroscopic techniques NMR, IR and elemental analysis. The cytoxicity screening had been carried out against five cancer cell lines: prostate cancer (PC-3), lung cancer (A-549), breast cancer (MCF-7), pancreas cancer (PaCa-2) and colon cancer (HT-29). Furthermore, the antioxidant activity, phospholipase A2-V and cyclooxygenases inhibitory activities of the target compounds 7a&b were evaluated and the new compounds showed potent activity (cytotoxicity IC50 range from 4.3 to 9.2 µm, antioxidant activity from 40% to 80%, COXs or LOX inhibitory activity from 1.92 µM to 8.21 µM). The docking of 7a&b was made to confirm the mechanism of action.
    Matched MeSH terms: Group V Phospholipases A2/antagonists & inhibitors; Group V Phospholipases A2/metabolism
  2. Fulltext Prevalence, virulence and antifungal activity of C. albicans isolated from infected root canals
    Abraham SB, Al Marzooq F, Himratul-Aznita WH, Ahmed HMA, Samaranayake LP
    BMC Oral Health, 2020 12 01;20(1):347.
    PMID: 33256696 DOI: 10.1186/s12903-020-01347-5
    BACKGROUND: There is limited data on the prevalence of Candida species in infected root canal systems of human teeth. We attempted to investigate the prevalence, genotype, virulence and the antifungal susceptibility of Candida albicans isolated from infected root canals of patients with primary and post-treatment infections in a UAE population.

    METHODS: Microbiological samples from 71 subjects with infected root canals were aseptically collected, and cultured on Sabouraud dextrose agar, and C. albicans was identified using multiplex polymerase chain reaction, and the isolates were further subtyped using ABC genotyping system. Their relative virulence was compared using further four archival samples of endodontic origin from another geographical region, and four more salivary isolates, as controls. The virulence attributes compared were biofilm formation, and production of phospholipase and haemolysin, and the susceptibility to nystatin, amphotericin B, ketoconazole, and fluoconazole was also tested.

    RESULTS: 4 out of 71 samples (5.6%) yielded Candida species. On analysis of variance among the groups, the intracanal isolates, mainly Genotype A, possessed a high degree of phospholipase and haemolysin activity (p 

    Matched MeSH terms: Phospholipases
  3. One-step analysis of growth kinetics of mesophilic Bacillus cereus in liquid egg yolk during treatment with phospholipase A2: Model development and validation
    Ahmad NH, Huang L, Juneja V
    Food Res Int, 2024 Jan;176:113786.
    PMID: 38163703 DOI: 10.1016/j.foodres.2023.113786
    Liquid egg yolk (LEY) is often treated with phospholipase A2 (PLA2) to improve its emulsifying capacity and thermal stability. However, this process may allow certain pathogens to grow. The objective of this study was to evaluate the growth kinetics of mesophilic Bacillus cereus in LEY during PLA2 treatment. Samples, inoculated with B. cereus vegetative cells, were incubated isothermally at different temperatures between 9 and 50 °C to observe the bacterial growth and survival. Under the observation conditions, bacterial growth occurred between 15 and 48 °C, but not at 9 and 50 °C. The growth curves were analyzed using the USDA IPMP-Global Fit, with the no-lag phase model as the primary model in combination with either the cardinal temperatures model (CTM) or the Huang square-root model (HSRM) as the secondary model. While similar maximum growth temperatures (Tmax) were determined (48.4 °C for HSRM and 48.1 °C for CTM), the minimum growth temperature (Tmin) of the HSRM more accurately described the lower limit (9.26 °C), in contrast to 6.51 °C for CTM, suggesting that the combination of the no-lag phase model and HSRM was more suitable to describe the growth of mesophilic B. cereus in LEY. The root mean square error (RMSE) of model validation and development was <0.5 log CFU/g, indicating the combination of the no-lag phase model and HSRM could predict the growth of mesophilic B. cereus in LEY during PLA2 treatment. The results of this study may allow the food industry to choose a suitable temperature for PLA2 treatment of LEY to prevent the growth of mesophilic B. cereus.
    Matched MeSH terms: Phospholipases; Phospholipases A2
  4. Fulltext High sPLA2-IIA level is associated with eicosanoid metabolism in patients with bacterial sepsis syndrome
    Ahmad NS, Tan TL, Arifin KT, Ngah WZW, Yusof YAM
    PLoS One, 2020;15(3):e0230285.
    PMID: 32160261 DOI: 10.1371/journal.pone.0230285
    The aim of this study was to determine the association between secretory phospholipase A2 group IIA (sPLA2-IIA) and eicosanoid pathway metabolites in patients with bacterial sepsis syndrome (BSS). Levels of sPLA2-IIA, eicosanoids prostaglandin (PG)E2, PGD synthase were quantified in the sera from patients confirmed to have bacterial sepsis (BS; N = 45), bacterial severe sepsis/septic shock (BSS/SS; N = 35) and healthy subjects (N = 45). Cyclooxygenase (COX)-1 and COX-2 activities were analyzed from cell lysate. Serum levels of sPLA2-IIA, PGE2, and PGDS increased significantly in patients with BS and BSS/SS compared to healthy subjects (p<0.05). COX-2 activity was significantly increased in patients with BS compared to healthy subjects (p<0.05), but not COX-1 activity. Binary logistic regression analysis showed that sPLA2-IIA and PGE2 were independent factors predicting BSS severity. In conclusion, high level of sPLA2-IIA is associated with eicosanoid metabolism in patients with BSS.
    Matched MeSH terms: Group II Phospholipases A2/blood*
  5. Effects of novel diarylpentanoid analogues of curcumin on secretory phospholipase A2 , cyclooxygenases, lipo-oxygenase, and microsomal prostaglandin E synthase-1
    Ahmad W, Kumolosasi E, Jantan I, Bukhari SN, Jasamai M
    Chem Biol Drug Des, 2014 Jun;83(6):670-81.
    PMID: 24406103 DOI: 10.1111/cbdd.12280
    Arachidonic acid and its metabolites have generated a heightened interest due to their significant role in inflammation. Inhibiting the enzymes involved in arachidonic acid metabolism has been considered as the synergistic anti-inflammatory effect. A series of novel curcumin diarylpentanoid analogues were synthesized and evaluated for their inhibitory effects on activity of secretory phospholipase A2 , cyclooxygenases, soybean lipo-oxygenase as well as microsomal prostaglandin E synthase-1. Among the curcumin analogues, compounds 3, 6, 9, 12, and 17 exhibited strong inhibition of secretory phospholipase A2 activity, with IC50 values ranging from 5.89 to 11.02 μm. Seven curcumin analogues 1, 3, 6, 7, 9, 11, and 12 showed inhibition of cyclooxygenases-2 with IC50 values in the range of 46.11 to 94.86 μm, which were lower than that of curcumin. Compounds 3, 6, 7, 12, and 17 showed strong inhibition of lipo-oxygenase enzyme activity. Preliminary screening of diarylpentanoid curcumin analogues for microsomal prostaglandin E synthase-1 activity revealed that four diarylpentanoid curcumin analogues 5, 6, 7, and 13 demonstrated higher inhibition of microsomal prostaglandin E synthase-1 activity with IC50 ranging from 2.41 to 4.48 μm, which was less than that of curcumin. The present results suggest that some of these diarylpentanoid analogues were able to inhibit the activity of these enzymes. This raises the possibility that diarylpentanoid analogues of curcumin might serve as useful starting point for the design of improved anti-inflammatory agents.
    Matched MeSH terms: Phospholipases A2, Secretory/metabolism*
  6. Fulltext New quinoxalinone inhibitors targeting secreted phospholipase A2 and α-glucosidase
    Alasmary FAS, Alnahdi FS, Ben Bacha A, El-Araby AM, Moubayed N, Alafeefy AM, et al.
    J Enzyme Inhib Med Chem, 2017 Dec;32(1):1143-1151.
    PMID: 28856929 DOI: 10.1080/14756366.2017.1363743
    Elevated blood glucose and increased activities of secreted phospholipase A2 (sPLA2) are strongly linked to coronary heart disease. In this report, our goal was to develop small heterocyclic compound that inhibit sPLA2. The title compounds were also tested against α-glucosidase and α-amylase. This array of enzymes was selected due to their implication in blood glucose regulation and diabetic cardiovascular complications. Therefore, two distinct series of quinoxalinone derivatives were synthesised; 3-[N'-(substituted-benzylidene)-hydrazino]-1H-quinoxalin-2-ones 3a-f and 1-(substituted-phenyl)-5H-[1,2,4]triazolo[4,3-a]quinoxalin-4-ones 4a-f. Four compounds showed promising enzyme inhibitory effect, compounds 3f and 4b-d potently inhibited the catalytic activities of all of the studied proinflammatory sPLA2. Compound 3e inhibited α-glucosidase (IC50 = 9.99 ± 0.18 µM); which is comparable to quercetin (IC50 = 9.93 ± 0.66 µM), a known inhibitor of this enzyme. Unfortunately, all compounds showed weak activity against α-amylase (IC50 > 200 µM). Structure-based molecular modelling tools were utilised to rationalise the SAR compared to co-crystal structures with sPLA2-GX as well as α-glucosidase. This report introduces novel compounds with dual activities on biochemically unrelated enzymes mutually involved in diabetes and its complications.
    Matched MeSH terms: Phospholipases A2, Secretory/antagonists & inhibitors*; Phospholipases A2, Secretory/metabolism
  7. 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 A/genetics*; Phospholipases A/isolation & purification; Phospholipases A/chemistry*; Phospholipases A2
  8. Effect of phospholipase C treatment on the activity of the particulate cyclic nucleotide phosphodiesterase of rat brain
    Azila N, Ong KK
    Int. J. Biochem., 1989;21(10):1157-9.
    PMID: 2555229
    1. The activity of cAMP phosphodiesterase (PDE) was studied in a 10,000 g particulate fraction prepared from rat brain. 2. Phospholipase C such as sphingomyelin choline phosphodiesterase (SMase), phosphatidylinositol phosphodiesterase (PIase) and phosphatidylcholine phosphohydrolase (PCase) were used to deplete phospholipid(s) from the particulate fraction and their effects on PDE activity were investigated. 3. Treatment with SMase or PIase did not affect PDE activity whereas treatment with PCase resulted in inhibition. 4. It was also found that the PCase used not only hydrolyzed phosphatidylcholine but also other phospholipids such as phosphatidylethanolamine, phosphatidylserine and sphingomyelin.
    Matched MeSH terms: Type C Phospholipases/pharmacology
  9. Haemolytic and phospholipase A activities of the tentacle extract of Catostylus mosaicus
    Azila N, Othman I
    Biochem. Int., 1990;20(2):291-9.
    PMID: 1969267
    An extract prepared from the tentacle of Catostylus mosaicus was shown to lyse erythrocytes from rat, rabbit and human to a different extent; those from the rat being most susceptible followed by those from rabbit and human. The haemolytic activity was dependent on the concentration of crude extract protein exhibiting a sigmoidal curve. Only 60% of the haemolytic activity was retained after treament with heat and proteolytic enzyme. The extract was devoid of hydrolytic enzymes normally present in venoms except for phospholipase A activity, which resulted in the hydrolysis of membrane phospholipids with concomittant appearance of their lyso-derivatives.
    Matched MeSH terms: Phospholipases/metabolism*; Phospholipases A/metabolism*
  10. Reduction of cyclic AMP phosphodiesterase activity of several subcellular fractions of rat brain after pretreatment with phospholipase C
    Azila N, Kuppusamy UR, Ong KK
    Biochem. Int., 1989 Nov;19(5):1077-85.
    PMID: 2561441
    Cyclic AMP phosphodiesterase (PDE) activity was assayed in the plasma membrane, mitochondrial and microsomal fractions of rat brain. The specific activity of the enzyme was highest in the plasma membrane fraction followed by mitochondrial and then the microsomal fraction. Phosphodiesterase activity of all three fractions was reduced after pretreatment with lecithinase C (PCase) from Clostridium perfringens but less markedly affected by the pretreatment with sphingomyelinase (SMase) from human placenta. The PDE activity of the plasma membrane fraction was more sensitive to PCase treatment compared with the other two particulate fractions, which showed only a slight loss of activity. Temperature seemed to affect PDE activity of the plasma membrane. The enzyme was quite stable at 30 degrees C but its activity dropped by approximately 46% at 37 degrees C after 90 min of incubation. Pretreatment of the plasma membrane at 30 degrees C with PCase at a concentration of more than 5 U caused a marked loss of PDE activity and the decrease in activity reached a plateau at concentrations above 10 U.
    Matched MeSH terms: Type C Phospholipases/pharmacology*
  11. Phospholipase A2 group v in benign familial fleck retina in a set of triplets
    Bin NJ, Heng HM, Poh R, Noor SM, Subrayan V
    Retina, 2015 Jun;35(6):1266-72.
    PMID: 25549071 DOI: 10.1097/IAE.0000000000000446
    To evaluate the association of phospholipase A2, Group V (PLA2G5), with benign familial fleck retina in a consanguineous family with triplets.
    Matched MeSH terms: Group V Phospholipases A2/genetics*
  12. Pharmacological evaluation and docking studies of α,β-unsaturated carbonyl based synthetic compounds as inhibitors of secretory phospholipase A₂, cyclooxygenases, lipoxygenase and proinflammatory cytokines
    Bukhari SN, Lauro G, Jantan I, Bifulco G, Amjad MW
    Bioorg Med Chem, 2014 Aug 1;22(15):4151-61.
    PMID: 24938495 DOI: 10.1016/j.bmc.2014.05.052
    Arachidonic acid and its metabolites have generated high level of interest among researchers due to their vital role in inflammation. The inhibition of enzymes involved in arachidonic acid metabolism has been considered as synergistic anti-inflammatory effect. A series of novel α,β-unsaturated carbonyl based compounds were synthesized and evaluated for their inhibitory activity on secretory phospholipase A₂ (sPLA₂), cyclooxygenases (COX), soybean lipoxygenase (LOX) in addition to proinflammatory cytokines comprising IL-6 and TNF-α. Six α,β-unsaturated carbonyl based compounds (2, 3, 4, 12, 13 and 14) exhibited strong inhibition of sPLA₂ activity, with IC₅₀ values in the range of 2.19-8.76 μM. Nine compounds 1-4 and 10-14 displayed inhibition of COX-1 with IC₅₀ values ranging from 0.37 to 1.77 μM (lower than that of reference compound), whereas compounds 2, 10, 13 and 14 strongly inhibited the COX-2. The compounds 10-14 exhibited strong inhibitory activity against LOX enzyme. All compounds were evaluated for the inhibitory activities against LPS-induced TNF-α and IL-6 release in the macrophages. On the basis of screening results, five active compounds 3, 4, 12, 13 and 14 were found strong inhibitors of TNF-α and IL-6 release in a dose-dependent manner. Molecular docking experiments were performed to clarify the molecular aspects of the observed COX and LOX inhibitory activities of the investigated compounds. Present findings increases the possibility that these α,β-unsaturated carbonyl based compounds might serve as beneficial starting point for the design and development of improved anti-inflammatory agents.
    Matched MeSH terms: Phospholipases A2, Secretory/antagonists & inhibitors*; Phospholipases A2, Secretory/metabolism
  13. Anti-inflammatory trends of new benzimidazole derivatives
    Bukhari SN, Lauro G, Jantan I, Fei Chee C, Amjad MW, Bifulco G, et al.
    Future Med Chem, 2016 Oct;8(16):1953-1967.
    PMID: 27654499
    In present study, the anti-inflammatory activities of a new series of benzimidazole derivatives were studied, investigating their inhibition of secretory phospholipase A2, lipoxygenase, COXs and lipopolysaccharide-induced secretion of TNF-α and IL-6 in mouse RAW264.7 macrophages.
    Matched MeSH terms: Phospholipases A2, Secretory
  14. Fulltext A Biochemical and Pharmacological Characterization of Phospholipase A2 and Metalloproteinase Fractions from Eastern Russell's Viper (Daboia siamensis) Venom: Two Major Components Associated with Acute Kidney Injury
    Chaisakul J, Khow O, Wiwatwarayos K, Rusmili MRA, Prasert W, Othman I, et al.
    Toxins (Basel), 2021 Jul 26;13(8).
    PMID: 34437392 DOI: 10.3390/toxins13080521
    Acute kidney injury (AKI) following Eastern Russell's viper (Daboia siamensis) envenoming is a significant symptom in systemically envenomed victims. A number of venom components have been identified as causing the nephrotoxicity which leads to AKI. However, the precise mechanism of nephrotoxicity caused by these toxins is still unclear. In the present study, we purified two proteins from D. siamensis venom, namely RvPLA2 and RvMP. Protein identification using LCMS/MS confirmed the identity of RvPLA2 to be snake venom phospholipase A2 (SVPLA2) from Thai D. siamensis venom, whereas RvMP exhibited the presence of a factor X activator with two subunits. In vitro and in vivo pharmacological studies demonstrated myotoxicity and histopathological changes of kidney, heart, and spleen. RvPLA2 (3-10 µg/mL) caused inhibition of direct twitches of the chick biventer cervicis muscle preparation. After administration of RvPLA2 or RvMP (300 µg/kg, i.p.) for 24 h, diffuse glomerular congestion and tubular injury with minor loss of brush border were detected in envenomed mice. RvPLA2 and RvMP (300 µg/kg; i.p.) also induced congestion and tissue inflammation of heart muscle as well as diffuse congestion of mouse spleen. This study showed the significant roles of PLA2 and SVMP in snake bite envenoming caused by Thai D. siamensis and their similarities with observed clinical manifestations in envenomed victims. This study also indicated that there is a need to reevaluate the current treatment strategies for Thai D. siamensis envenoming, given the potential for irreversible nephrotoxicity.
    Matched MeSH terms: Phospholipases A2/isolation & purification; Phospholipases A2/toxicity*; Phospholipases A2/chemistry
  15. Enzymatic characterisation of clinical isolates of Cryptococcus neoformans, Cryptococcus gattii and other environmental Cryptococcus spp
    Chan MY, Tay ST
    Mycoses, 2010 Jan;53(1):26-31.
    PMID: 19389064 DOI: 10.1111/j.1439-0507.2008.01654.x
    This study compared the enzymatic activity of clinical isolates of Cryptococcus neoformans, Cryptococcus gattii, environmental isolates of C. neoformans and non-neoformans Cryptococcus. Most of the cryptococcal isolates investigated in this study exhibited proteinase and phospholipase activities. Laccase activity was detected from all the C. neoformans and C. gattii isolates, but not from the non-neoformans Cryptococcus isolates. There was no significant difference in the proteinase, phospholipase and laccase activities of C. neoformans and C. gattii. However, significant difference in the enzymatic activities of beta-glucuronidase, alpha-glucosidase, beta-glucosidase and N-acetyl-beta-glucosaminidase between C. neoformans and C. gattii isolates was observed in this study. Environmental isolates of C. neoformans exhibited similar enzymatic profiles as the clinical isolates of C. neoformans, except for lower proteinase and laccase activities.
    Matched MeSH terms: Phospholipases/analysis
  16. Fulltext Candida albicans isolates from a Malaysian hospital exhibit more potent phospholipase and haemolysin activities than non-albicans Candida isolates
    Chin VK, Foong KJ, Maha A, Rusliza B, Norhafizah M, Ng KP, et al.
    Trop Biomed, 2013 Dec;30(4):654-62.
    PMID: 24522136 MyJurnal
    This study was aimed at determining the phospholipase and haemolysin activity of Candida isolates in Malaysia. A total of 37 Candida clinical isolates representing seven species, Candida albicans (12), Candida tropicalis (8), Candida glabrata (4), Candida parapsilosis (1), Candida krusei (4), Candida orthopsilosis (1) and Candida rugosa (7) were tested. In vitro phospholipase activity was determined by using egg yolk plate assay whereas in vitro haemolysin activity was tested by using blood plate assay on sheep blood Sabouraud's dextrose agar (SDA) enriched with glucose. Phospholipase activity was detected in 75% (9 out of 12) of the C. albicans isolates. Among the 25 non- C. albicans Candida isolates, phospholipase activity was detected in only 24% of these isolates. The phospholipase activity of C. albicans was significantly higher than that of the non- C. albicans Candida isolates (P=0.002). Haemolysin activity was detected in 100% of the C. albicans, C. tropicalis, C. glabrata, C. krusei, C. parapsilosis, and C. orthopsilosis isolates while 75% of the C. krusei isolates and 12.3% of the C. rugosa isolates showed haemolysin activity. The haemolytic activity of C. albicans was significantly higher than that of the non- C. albicans Candida isolates (P=0.0001).The findings in this study indicate that C. albicans isolates in Malaysia may possess greater virulence potential than the non-albicans species.
    Matched MeSH terms: Phospholipases/analysis*
  17. 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 A/genetics; Phospholipases A/chemistry*; Phospholipases A2
  18. 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
  19. Fulltext Synthesis and evaluation of anticancer, antiphospholipases, antiproteases, and antimetabolic syndrome activities of some 3H-quinazolin-4-one derivatives
    El-Sayed NNE, Almaneai NM, Ben Bacha A, Al-Obeed O, Ahmad R, Abdulla M, et al.
    J Enzyme Inhib Med Chem, 2019 Dec;34(1):672-683.
    PMID: 30821525 DOI: 10.1080/14756366.2019.1574780
    Some new 3H-quinazolin-4-one derivatives were synthesised and screened for anticancer, antiphospholipases, antiproteases, and antimetabolic syndrome activities. Compound 15d was more potent in reducing the cell viabilities of HT-29 and SW620 cells lines to 38%, 36.7%, compared to 5-FU which demonstrated cell viabilities of 65.9 and 42.7% respectively. The IC50 values of 15d were ∼20 µg/ml. Assessment of apoptotic activity revealed that 15d decreased the cell viability by down regulating Bcl2 and BclxL. Moreover, compounds, 8j, 8d/15a/15e, 5b, and 8f displayed lowered IC50 values than oleanolic acid against proinflammatory isoforms of hGV, hG-X, NmPLA2, and AmPLA2. In addition, 8d, 8h, 8j, 15a, 15b, 15e, and 15f showed better anti-α-amylase than quercetin, whereas 8g, 8h, and 8i showed higher anti-α-glucosidase activity than allopurinol. Thus, these compounds can be considered as potential antidiabetic agents. Finally, none of the compounds showed higher antiproteases or xanthine oxidase activities than the used reference drugs.
    Matched MeSH terms: Phospholipases/antagonists & inhibitors*; Phospholipases/metabolism
  20. Proteomics, functional characterization and antivenom neutralization of the venom of Pakistani Russell's viper (Daboia russelii) from the wild
    Faisal T, Tan KY, Sim SM, Quraishi N, Tan NH, Tan CH
    J Proteomics, 2018 07 15;183:1-13.
    PMID: 29729992 DOI: 10.1016/j.jprot.2018.05.003
    The venom proteome of wild Pakistani Russell's viper (Daboia russelii) was investigated through nano-ESI-LCMS/MS of the reverse-phase HPLC fractions. A total of 54 venom proteins were identified and clustered into 11 protein families. Phospholipase A2 (PLA2, 63.8%) and Kunitz-type serine protease inhibitor (KSPI, 16.0%) were most abundant, followed by snake venom serine protease (SVSP, 5.5%, mainly Factor V activating enzyme), vascular endothelial growth factor (VEGF, 4.3%), snake venom metalloproteinase (SVMP, 2.5%, mainly Factor X activating enzyme) and phosphodiesterase (PDE, 2.5%). Other minor proteins include cysteine-rich secretory protein (CRiSP), snake venom C-type lectin/lectin-like protein (snaclec), nerve growth factor, L-amino acid oxidase and 5'-nucleotidase. PLA2, KSPI, SVSP, snaclec and SVMP are hemotoxic proteins in the venom. The study indicated substantial venom variation in D. russelii venoms of different locales, including 3 Pakistani specimens kept in the USA. The venom exhibited potent procoagulant activity on human plasma (minimum clotting dose = 14.5 ng/ml) and high lethality (rodent LD50 = 0.19 μg/g) but lacked hemorrhagic effect locally. The Indian VINS Polyvalent Antivenom bound the venom immunologically in a concentration-dependent manner. It moderately neutralized the venom procoagulant and lethal effects (normalized potency against lethality = 2.7 mg venom neutralized per g antivenom).

    BIOLOGICAL SIGNIFICANCE: Comprehensive venom proteomes of D. russelii from different locales will facilitate better understanding of the geographical variability of the venom in both qualitative and quantitative terms. This is essential to provide scientific basis for the interpretation of differences in the clinical presentation of Russell's viper envenomation. The study revealed a unique venom proteome of the Pakistani D. russelii from the wild (Indus Delta), in which PLA2 predominated (~60% of total venom proteins). The finding unveiled remarkable differences in the venom compositions between the wild (present study) and the captive specimens reported previously. The integration of toxicity tests enabled the correlation of the venom proteome with the envenoming pathophysiology, where the venom showed potent lethality mediated through coagulopathic activity. The Indian VINS Polyvalent Antivenom (VPAV) showed binding activity toward the venom protein antigens; however the immunorecognition of small proteins and PLA2-dominating fractions was low to moderate. Consistently, the antivenom neutralized the toxicity of the wild Pakistani Russell's viper venom at moderate efficacies. Our results suggest that it may be possible to enhance the Indian antivenom potency against the Pakistani viper venom by the inclusion of venoms from a wider geographical range including that from Pakistan into the immunogen formulation.

    Matched MeSH terms: Phospholipases A2/analysis
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