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Katan M, Moon YP, Paik MC, Wolfert RL, Sacco RL, Elkind MSV. Lipoprotein-associated phospholipase A2 is associated with atherosclerotic stroke risk: the Northern Manhattan Study. PLoS One 2014; 9:e83393. [PMID: 24416164 PMCID: PMC3886969 DOI: 10.1371/journal.pone.0083393] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 11/04/2013] [Indexed: 11/18/2022] Open
Abstract
Background Lipoprotein-associated phospholipase A2 (LpPLA2) levels are associated with stroke, though whether this extends to all populations and stroke subtypes is unknown. Methods Serum samples from stroke-free community participants in the Northern Manhattan Study were assayed for LpPLA2 mass and activity. Participants were followed annually for stroke. Cox-proportional-hazard models were fitted to estimate hazard-ratios and 95% confidence intervals (HR, 95% CI) for the association of LpPLA2 levels with ischemic stroke (IS), after adjusting for demographic and medical risk factors. Results Serum samples were available in 1946 participants, of whom 151 (7.8%) experienced a first IS during median follow-up 11 years. Mean age was 69 (SD 10), 35.6% were men, 20% non-Hispanic Whites, 22% non-Hispanic Blacks, and 55% Hispanics. LpPLA2 mass and activity levels were not associated with overall IS risk. LpPLA2 mass but not activity levels were associated with strokes due to large artery atherosclerosis (LAA; adjusted HR per SD 1.55, 95% CI 1.17–2.04). There was a dose-response relationship with LAA (compared to first quartile, 2nd quartile HR = 1.43, 95% CI 0.23–8.64; 3rd quartile HR = 4.47, 95% CI 0.93–21.54; 4th quartile HR = 5.07, 95% CI 1.07–24.06). The associations between LpPLA2-mass and LAA-stroke risk differed by race-ethnicity (p = 0.01); LpPLA2-mass was associated with increased risk of LAA among non-Hispanic Whites (adjusted HR per SD 1.44, 95% CI 0.98–2.11), but not other race-ethnic groups. Conclusion LpPLA2-mass levels were associated with risk of atherosclerotic stroke among non-Hispanic White participants, but not in other race-ethnic groups in the cohort. Further study is needed to confirm these race-ethnic differences and the reasons for them.
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Affiliation(s)
- Mira Katan
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
- Department of Neurology, University Hospital of Zurich, Switzerland
- * E-mail:
| | - Yeseon P. Moon
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
| | - Myunghee C. Paik
- Department of Biostatistics, Mailman School of Public Health, Columbia University New York, New York, United States of America
| | | | - Ralph L. Sacco
- Department of Neurology, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
- Departments of Epidemiology and Human Genetics, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
| | - Mitchell S. V. Elkind
- Department of Neurology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
- Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York, United States of America
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Abstract
Since the phospholipase B (PLB) was reported as a deacylase of both lecithin and lysolecithin yielding fatty acids and glycerophosphocholine (GPC), there was a question as to whether it is a single enzyme or a mixture of a phospholipase A2 (PLA2) and a lysophospholipase (LPL). We purified the PLB in Penicillium notatum and showed that it catalyzed deacylation of sn-1 and sn-2 fatty acids of 1,2-diacylphospholipids and also sn-1 or sn-2 fatty acids of 1- or 2-monoacylphospholipids (lysophospholipids). Further, it also has a monoacyllipase activity. The purified PLB is a glycoprotein with m.w. of 91,300. The sugar moiety is M9 only and the protein moiety consists of 603 amino acids. PLB, different from PLA2, shows other enzymatic activities, such as transacylase, lipase and acylesterase. PLB activity is influenced by various substances, e.g. detergents, deoxycholate, diethylether, Fe(3+), and endogenous protease. Therefore, PLB might have broader roles than PLA2 in vivo. The database shows an extensive sequence similarity between P. notatum PLB and fungal PLB, cPLA2 and patatin, suggesting a homologous relationship. The catalytic triad of cPLA2, Ser, Asp and Arg, is also present in P. notatum PLB. Other related PLBs, PLB/Lipases are discussed.
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203
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Aslan M, Özcan F, Tuzcu H, Kıraç E, Elpek GO. Inhibition of neutral sphingomyelinase decreases arachidonic acid mediated inflammation in liver ischemia-reperfusion injury. Int J Clin Exp Pathol 2014; 7:7814-23. [PMID: 25550821 DOI: pmid/25550821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 10/16/2014] [Indexed: 02/08/2023]
Abstract
This study aimed to determine the role of selective neutral sphingomyelinase (N-SMase) inhibition on arachidonic acid (AA) mediated inflammation following liver ischemia-reperfusion (IR) injury. Selective N-SMase inhibitor was administered via intraperitoneal injections. Liver IR injury was created by clamping blood vessels supplying the median and left lateral hepatic lobes for 60 min, followed by 60 min reperfusion. Levels of AA in liver tissue were determined by multiple reaction monitoring (MRM) using ultra fast-liquid chromatography (UFLC) coupled with tandem mass spectrometry (MS/MS). Phospholipase A₂ (PLA₂), cyclooxygenase (COX) and prostaglandin E₂ (PGE₂) were measured in liver tissue. Arachidonic acid levels, activity of PLA₂, COX and PGE₂ levels were significantly increased in postischemic liver tissue compared to nonischemic controls. N-SMase inhibition significantly decreased COX activity and PGE₂ levels in postischemic liver. Future studies evaluating agents blocking N-SMase activity can facilitate the development of treatment strategies to alleviate inflammation in liver I/R injury.
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Affiliation(s)
- Mutay Aslan
- Department of Medical Biochemistry, Akdeniz University Faculty of Medicine Antalya 07070, Turkey
| | - Filiz Özcan
- Department of Medical Biochemistry, Akdeniz University Faculty of Medicine Antalya 07070, Turkey
| | - Hazal Tuzcu
- Department of Medical Biochemistry, Akdeniz University Faculty of Medicine Antalya 07070, Turkey
| | - Ebru Kıraç
- Department of Medical Biochemistry, Akdeniz University Faculty of Medicine Antalya 07070, Turkey
| | - Gulsum O Elpek
- Department of Pathology, Akdeniz University Faculty of Medicine Antalya 07070, Turkey
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D'Almeida RE, Isla MI, Vildoza EDL, Quispe C, Schmeda-Hirschmann G, Alberto MR. Inhibition of arachidonic acid metabolism by the Andean crude drug Parastrephia lucida (Meyen) Cabrera. J Ethnopharmacol 2013; 150:1080-1086. [PMID: 24432370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Parastrephia lucida (Meyen) Cabrera is used in the traditional medicine of Argentinean highlands as an antiseptic and anti-inflammatory medicinal plant. To give scientific support to the ethnopharmacological claim of Parastrephia lucida as an anti-inflammatory crude drug the effect of Parastrephia lucida extracts and fractions was assessed on key enzymes of the biosynthesis of pro-inflammatory eicosanoids mediators from arachidonic acid (AA). MATERIALS AND METHODS A bio-guided fractionation of the plant extract was carried out to find out the compounds or mixtures responsible for the anti-inflammatory effect. The extracts and fractions were tested in vitro for their ability to inhibit the enzymes cyclooxygenase (COX)-1 and COX-2, lipoxygenase (LOX) and phospholipase (sPLA2). Fractions were analyzed by HPLC-MS, HPLC-ESI-MS/MS and NMR to relate the effect with groups of secondary metabolites. RESULTS Parastrephia lucida was more effective inhibiting COX and sPLA2 than LOX. Assay-guided isolation led to the active fractions C and F which showed different effect on the selected enzymes. The fraction C was more effective inhibiting LOX while fraction F showed better activity against sPLA2 and COX-2. Both fractions were further worked-up following the isolation of the anti-inflammatory agents with the selected enzyme assays. The main compounds identified in the most active fractions were 5,4′-dihydroxi-7-methoxyflavanone, apigenin, apigenin methyl ether and apigenin trimethyl ether, methyl and dimethyl ethers from quercetin, kaempferol and luteolin methyl ether, ferulic acid esters, cinnamic acid and vanillin. CONCLUSIONS Parastrephia lucida extract inhibit AA metabolism via several enzymes. The results give support to the traditional use of this plant for the treatment of inflammatory disorders.
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205
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Fan F, Sun CW, Maier KG, Williams JM, Pabbidi MR, Didion SP, Falck JR, Zhuo J, Roman RJ. 20-Hydroxyeicosatetraenoic acid contributes to the inhibition of K+ channel activity and vasoconstrictor response to angiotensin II in rat renal microvessels. PLoS One 2013; 8:e82482. [PMID: 24324797 PMCID: PMC3853207 DOI: 10.1371/journal.pone.0082482] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 11/02/2013] [Indexed: 11/24/2022] Open
Abstract
The present study examined whether 20-hydroxyeicosatetraenoic acid (HETE) contributes to the vasoconstrictor effect of angiotensin II (ANG II) in renal microvessels by preventing activation of the large conductance Ca2+-activated K+ channel (KCa) in vascular smooth muscle (VSM) cells. ANG II increased the production of 20-HETE in rat renal microvessels. This response was attenuated by the 20-HETE synthesis inhibitors, 17-ODYA and HET0016, a phospholipase A2 inhibitor AACOF3, and the AT1 receptor blocker, Losartan, but not by the AT2 receptor blocker, PD123319. ANG II (10-11 to 10-6 M) dose-dependently decreased the diameter of renal microvessels by 41 ± 5%. This effect was blocked by 17-ODYA. ANG II (10-7 M) did not alter KCa channel activity recorded from cell-attached patches on renal VSM cells under control conditions. However, it did reduce the NPo of the KCa channel by 93.4 ± 3.1% after the channels were activated by increasing intracellular calcium levels with ionomycin. The inhibitory effect of ANG II on KCa channel activity in the presence of ionomycin was attenuated by 17-ODYA, AACOF3, and the phospholipase C (PLC) inhibitor U-73122. ANG II induced a peak followed by a steady-state increase in intracellular calcium concentration in renal VSM cells. 17-ODYA (10-5 M) had no effect on the peak response, but it blocked the steady-state increase. These results indicate that ANG II stimulates the formation of 20-HETE in rat renal microvessels via the AT1 receptor activation and that 20-HETE contributes to the vasoconstrictor response to ANG II by blocking activation of KCa channel and facilitating calcium entry.
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MESH Headings
- Angiotensin II/pharmacology
- Animals
- Calcium/metabolism
- Gene Expression
- Hydroxyeicosatetraenoic Acids/metabolism
- Ionomycin/pharmacology
- Male
- Microvessels/drug effects
- Microvessels/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Phospholipases A2/metabolism
- Potassium Channel Blockers/pharmacology
- Potassium Channels/metabolism
- Potassium Channels, Calcium-Activated/antagonists & inhibitors
- Potassium Channels, Calcium-Activated/metabolism
- Rats
- Receptors, Angiotensin/genetics
- Receptors, Angiotensin/metabolism
- Renal Circulation/drug effects
- Renal Circulation/physiology
- Type C Phospholipases/metabolism
- Vasoconstrictor Agents/pharmacology
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Affiliation(s)
- Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi, United States of America
| | - Cheng-Wen Sun
- Department of Pharmaceutical Sciences, North Dakota State University, Fargo, North Dakota, United States of America
| | - Kristopher G. Maier
- Division of Vascular Surgery and Endovascular Services, SUNY Upstate Medical University, Syracuse, New York, United States of America
| | - Jan M. Williams
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi, United States of America
| | - Malikarjuna R. Pabbidi
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi, United States of America
| | - Sean P. Didion
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi, United States of America
| | - John R. Falck
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Jialong Zhuo
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi, United States of America
| | - Richard J. Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, Mississippi, United States of America
- * E-mail:
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Stanca E, Serviddio G, Bellanti F, Vendemiale G, Siculella L, Giudetti AM. Down-regulation of LPCAT expression increases platelet-activating factor level in cirrhotic rat liver: potential antiinflammatory effect of silybin. Biochim Biophys Acta 2013; 1832:2019-26. [PMID: 23851051 DOI: 10.1016/j.bbadis.2013.07.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 06/24/2013] [Accepted: 07/03/2013] [Indexed: 02/08/2023]
Abstract
Cholestasis is one of the major causes of liver diseases. A chronic accumulation of toxic bile acids in the liver, which occurs in this condition, can induce fibrosis and cirrhosis. Inflammation is a fundamental component of acute and chronic cholestatic liver injury. Platelet-activating factor (PAF) is a proinflammatory lipid which may be generated by two independent pathways called the de novo and remodeling pathway being the last responsible for the synthesis of PAF during inflammation. In recent years a key role in PAF remodeling has been attributed to lysophosphatidylcholine acyltransferase (LPCAT) enzymes. Although the knowledge on their characteristic is growing, the exact mechanism of LPCAT in pathological conditions remains still unknown. Here, we reported that the level of lyso-PAF and PAF significantly increased in the liver of cirrhotic vs. control rats together with a significant decrease in both mRNA abundance and protein level of both LPCAT1 and LPCAT2. Acyltransferase activities of both LPCAT1 and LPCAT2 were parallel decreased in the liver of cirrhotic animals. Interestingly, treatment with silybin strongly decreased the level of both pro-inflammatory lipids and restored the activity and expression of both LPCAT1 and LPCAT2 of cirrhotic liver. Silybin effect was specific for LPCAT1 and LPCAT2 since it did not affect LPCAT3 mRNA abundance of cirrhotic liver.
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Affiliation(s)
- Eleonora Stanca
- Laboratory of Biochemistry and Molecular Biology, Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
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207
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Choi JM, Choi YH, Kim SK, Ahn KH, Won JH, Lim JH, Jang YJ, Lee S, Kim DH, Kim DK. (S)-tetrahydroisoquinoline alkaloid inhibits LPS-induced arachidonic acid release through downregulation of cPLA2 expression. Mol Cells 2013; 36:400-9. [PMID: 24293010 PMCID: PMC3887938 DOI: 10.1007/s10059-013-0078-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 09/10/2013] [Accepted: 09/15/2013] [Indexed: 01/24/2023] Open
Abstract
Sepsis, a systemic inflammatory response syndrome, remains a potentially lethal condition. (S)-1-α-Naphthylmethyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (CKD712) is noted as a drug candidate for sepsis. Many studies have demonstrated its significant anti-inflammatory effects. Here we first examined whether CKD712 inhibits lipopolysaccharide (LPS)-induced arachidonic acid (AA) release in the RAW 264.7 mouse monocyte cell line, and subsequently, its inhibitory mechanisms. CKD712 reversed LPS-associated morphological changes in the RAW 264.7 cells, and inhibited LPS-induced release of AA in a concentrationdependent manner. The inhibition was apparently due to the diminished expression of a cytosolic form of phospholipase A2 (cPLA2) by CKD712, resulting from reduced NF-κB activation. Furthermore, CKD712 inhibited the activation of ERK1/2 and SAP/JNK, but not of p38 MAPK. CKD712 had no effect on the activity or phosphorylation of cPLA2 and on calcium influx. Our results collectively suggest that CKD712 inhibits LPS-induced AA release through the inhibition of a MAPKs/NF-κB pathway leading to reduced cPLA2 expression in RAW 264.7 cells.
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Affiliation(s)
- Jong Min Choi
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Young Hwa Choi
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Seok Kyun Kim
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Kyong Hoon Ahn
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Jong Hoon Won
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - Joo Hyuk Lim
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | - You Jin Jang
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
| | | | | | - Dae Kyong Kim
- Department of Environmental and Health Chemistry, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea
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Hsu PY, Lee KK, Lee PS, Hu CC, Lin CH, Liu PC. Biochemical characterization of a phospholipase A2 from Photobacterium damselae subsp. piscicida. Z NATURFORSCH C 2013; 68:471-481. [PMID: 24601085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Photobacterium damselae subsp. piscicida (Phdp) is the causative agent of fish photobacteriosis (pasteurellosis) in cultured cobia (Rachycentron canadum) in Taiwan. A component was purified from the extracellular products (ECP) of the bacterium strain 9205 by fast protein liquid chromatography (FPLC) and identified as a phospholipase. An N-terminal sequence of 10 amino acid residues, QDQPNLDPGK, was determined by mass spectroscopy (MS) and found to be identical with that of another Phdp phospholipase (GenBank accession no. BAB85814) at positions 21 to 30. The corresponding gene sequence of the phospholipase (GenBank accession no. AB071137) was employed to design primers for amplification of the sequence by the polymerase chain reaction (PCR). The PCR products were transformed into Escherichia coli, and a recombinant protein product was obtained which was purified as a His-tag fusion protein by Ni-metal affinity chromatography. A single 43-kDa band was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Phosphatidylcholine was degraded by this protein to lysophosphatidylcholine and a fatty acid. These products were characterized by thin-layer (TLC) and gas chromatography (GC), respectively, allowing the identification of the protein as a phospholipase A2. The recombinant protein had maximum enzymatic activity between pH 4 and 7, and at 40 degrees C. The activity was inhibited by Zn(2+) and Cu(2+), activated by Ca(2+) and Mg(2+), and completely inactivated by dexamethasone and p-bromophenacyl bromide. A rabbit antiserum against the recombinant protein neutralized the phospholipase A2 activity in the ECP of Phdp strain 9205 and the recombinant protein itself. The recombinant protein was toxic to cobia of about 5 g weight with an LD50 value between 2 and 4 microg protein/g fish. The results revealed phospholipase A2 as a fish toxin in the ECP of Phdp strain 9205.
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Affiliation(s)
- Po-Yuan Hsu
- Department of Aquaculture, National Taiwan Ocean University, 2, Pei-Ning Road, Keelung, Taiwan
| | - Kuo-Kau Lee
- Department of Aquaculture, National Taiwan Ocean University, 2, Pei-Ning Road, Keelung, Taiwan
| | - Pei-Shan Lee
- Eastern Marine Biology Research Center, Fisheries Research Institute, 22, Wuquan Road, Chenggong Township, Taitung, Taiwan
| | - Chih-Chuang Hu
- Department of Aquaculture, National Taiwan Ocean University, 2, Pei-Ning Road, Keelung, Taiwan
| | - Cheng-Hui Lin
- Department of Aquaculture, National Taiwan Ocean University, 2, Pei-Ning Road, Keelung, Taiwan
| | - Ping-Chung Liu
- Department of Aquaculture, National Taiwan Ocean University, 2, Pei-Ning Road, Keelung, Taiwan
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209
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Venkatesh M, Gowda V. Synergistically acting PLA₂: peptide hemorrhagic complex from Daboia russelii venom. Toxicon 2013; 73:111-20. [PMID: 23872188 DOI: 10.1016/j.toxicon.2013.07.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 07/03/2013] [Accepted: 07/04/2013] [Indexed: 10/26/2022]
Abstract
Snake venoms are complex mixture of enzymatic and non-enzymatic proteins. Non-covalent protein-protein interaction leads to protein complexes, which bring about enhanced pharmacological injuries by their synergistic action. Here we report identification and characterization of a new Daboia russelii hemorrhagic complex I (DR-HC-I) containing phospholipase A₂ (PLA₂) and non-enzymatic peptide. DR-HC-I was isolated from the venom of D. russelii by CM-Shepadex-C25 and gel permeation chromatography. Individual components were purified and identified by RP-HPL chromatography, mass spectrometry and N-terminal amino acid sequencing. DR-HC-I complex was lethal to mice with the LD₅₀ dose of 0.7 mg/kg body weight with hemorrhagic and neurotoxic properties. DR-HC-I complex consists of non-hemorrhagic PLA₂ and neurotoxic non-enzymatic peptide. The non-enzymatic peptide quenched the intrinsic fluorescence of PLA₂ in a dose dependent manner, signifying the synergistic interaction between two proteins. PLA₂ and peptide toxin in a 5:2 M ratio induced skin hemorrhage in mice with MHD 20 μg. However, addition of ANS (1-Anilino-8-naphthalene sulfonate) to DR-HC-I complex inhibited skin hemorrhagic effect and also synergic interaction. But there was no impact on PLA₂ due to this synergistic interaction, and indirect hemolytic or plasma re-calcification activity. However, the synergistic interaction of PLA₂ and non-enzymatic peptide contributes to the enhanced venom-induced hemorrhage and toxicity of Daboia russellii venom.
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Affiliation(s)
- Madhukumar Venkatesh
- Department of Studies in Biochemistry, Manasagangotri, University of Mysore, Mysore 570006, Karnataka, India
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Martins DA, Rocha F, Castanheira F, Mendes A, Pousão-Ferreira P, Bandarra N, Coutinho J, Morais S, Yúfera M, Conceição LEC, Martínez-Rodríguez G. Effects of dietary arachidonic acid on cortisol production and gene expression in stress response in Senegalese sole (Solea senegalensis) post-larvae. Fish Physiol Biochem 2013; 39:1223-1238. [PMID: 23443720 DOI: 10.1007/s10695-013-9778-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2012] [Accepted: 02/18/2013] [Indexed: 06/01/2023]
Abstract
Dietary fatty acids, particularly arachidonic acid (ARA), affect cortisol and may influence the expression of genes involved in stress response in fish. The involvement of ARA on stress, lipid, and eicosanoid metabolism genes, in Senegalese sole, was tested. Post-larvae were fed Artemia presenting graded ARA levels (0.1, 0.4, 0.8, 1.7, and 2.3%, dry matter basis), from 22 to 35 days after hatch. Whole-body cortisol levels were determined, before and 3 h after a 2 min air exposure, as well as the expression of phospholipase A2 (PLA 2 ), cyclooxygenase-2 (COX-2), steroidogenic acute regulatory protein (StAR), glucocorticoid receptors (GRs), phosphoenolpyruvate carboxykinase (PEPCK), and peroxisome proliferator-activated receptor alpha (PPARα). Relative growth rate (6.0-7.8% day(-1)) and survival at the end of the experiment (91-96%) and after stress (100%) were unaffected. Fish reflected dietary ARA content and post-stress cortisol increased with ARA supply up to 1.7%, whereas 2.3% ARA seemed to enhance basal cortisol slightly and alter the response to stress. Results suggested that elevating StAR transcription might not be necessary for a short-term response to acute stress. Basal cortisol and PLA 2 expression were strongly correlated, indicating a potential role for this enzyme in steroidogenesis. Under basal conditions, larval ARA was associated with GR1 expression, whereas the glucocorticoid responsive gene PEPCK was strongly related with cortisol but not GR1 mRNA levels, suggesting the latter might not reflect the amount of GR1 protein in sole. Furthermore, a possible role for PPARα in the expression of PEPCK following acute stress is proposed.
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Affiliation(s)
- Dulce Alves Martins
- Centro de Ciências do Mar do Algarve, Universidade do Algarve, Campus de Gambelas, 8005-139, Faro, Portugal,
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211
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Smith RC, Kizito C, Rasgon JL, Jacobs-Lorena M. Transgenic mosquitoes expressing a phospholipase A(2) gene have a fitness advantage when fed Plasmodium falciparum-infected blood. PLoS One 2013; 8:e76097. [PMID: 24098427 PMCID: PMC3788000 DOI: 10.1371/journal.pone.0076097] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 08/20/2013] [Indexed: 11/18/2022] Open
Abstract
Background Genetically modified mosquitoes have been proposed as an alternative strategy to reduce the heavy burden of malaria. In recent years, several proof-of-principle experiments have been performed that validate the idea that mosquitoes can be genetically modified to become refractory to malaria parasite development. Results We have created two transgenic lines of Anophelesstephensi, a natural vector of Plasmodium falciparum, which constitutively secrete a catalytically inactive phospholipase A2 (mPLA2) into the midgut lumen to interfere with Plasmodium ookinete invasion. Our experiments show that both transgenic lines expressing mPLA2 significantly impair the development of rodent malaria parasites, but only one line impairs the development of human malaria parasites. In addition, when fed on malaria-infected blood, mosquitoes from both transgenic lines are more fecund than non-transgenic mosquitoes. Consistent with these observations, cage experiments with mixed populations of transgenic and non-transgenic mosquitoes show that the percentage of transgenic mosquitoes increases when maintained on Plasmodium-infected blood. Conclusions Our results suggest that the expression of an anti-Plasmodium effector gene gives transgenic mosquitoes a fitness advantage when fed malaria-infected blood. These findings have important implications for future applications of transgenic mosquito technology in malaria control.
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Affiliation(s)
- Ryan C. Smith
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Christopher Kizito
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Jason L. Rasgon
- Department of Entomology, Center for Infectious Disease Dynamics and the Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Marcelo Jacobs-Lorena
- Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail:
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Pryvrots'ka IB, Kuchmerovs'ka TM. [Oxidative stress in blood leukocytes, pro/antioxidant status and fatty acids composition of pancreas lipids at experimental acute pancreatitis in rats]. Ukr Biokhim Zh (1999) 2013; 85:124-136. [PMID: 24479330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In an experimental model of acute pancreatitis (AP) in rats no alteration in leukocyte's viability was found by flow cytometry as compared to control. After 1 day of AP production of reactive oxygen forms in granulocytes was increased more than 5 times, but after 3 days their level was decreased. Alterations of pro/antioxidant status and specific changes in the fatty acid composition in the pancreas were established. With the development of AP, the processes of lipids peroxidation were intensified while antioxidant system was altered, that was evidenced by inflammation in the pancreas. In these conditions, the increase of phospholipase A2 activity was accompanied by significant changes of fatty acid composition of the total lipids in the pancreas. This increased relative total content of saturated fatty acids, in particular myristic, palmitic and stearic acid increased, while the total content of polyunsaturated essential fatty acids omega-3 (linolenic, eicosapentaenoic, dokozapentayenoic, docosahexaenoic) decreased. The preparation containing omega-3 polyunsaturated fatty acids partially normalized the lipid and fatty acids composition as well as prooxidant-antioxidant system.
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MESH Headings
- Animals
- Animals, Outbred Strains
- Arginine
- Fatty Acids/analysis
- Fatty Acids/metabolism
- Fatty Acids, Omega-3/administration & dosage
- Fatty Acids, Unsaturated/analysis
- Fatty Acids, Unsaturated/metabolism
- Granulocytes/drug effects
- Granulocytes/metabolism
- Granulocytes/pathology
- Leukocytes, Mononuclear/drug effects
- Leukocytes, Mononuclear/metabolism
- Leukocytes, Mononuclear/pathology
- Lipid Peroxidation/drug effects
- Male
- Oxidative Stress
- Pancreas/drug effects
- Pancreas/metabolism
- Pancreas/pathology
- Pancreatitis, Acute Necrotizing/chemically induced
- Pancreatitis, Acute Necrotizing/drug therapy
- Pancreatitis, Acute Necrotizing/metabolism
- Pancreatitis, Acute Necrotizing/pathology
- Phospholipases A2/metabolism
- Rats
- Reactive Oxygen Species/antagonists & inhibitors
- Reactive Oxygen Species/metabolism
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213
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Talib LL, Valente KD, Vincentiis S, Gattaz WF. Correlation between platelet and brain PLA(2) activity. Prostaglandins Leukot Essent Fatty Acids 2013; 89:265-8. [PMID: 23880350 DOI: 10.1016/j.plefa.2013.07.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 06/26/2013] [Accepted: 07/02/2013] [Indexed: 11/17/2022]
Abstract
The phospholipase A2 (PLA2) enzymes have been implicated in several neuropsychiatry disorders and activity alterations have been described in brain and platelet. Since brain tissue is not readily available for the measurement of PLA2 activity, it would be of interest to test directly whether PLA2 activities in both tissues are correlated. We performed this task assessing PLA2 activity in platelets and hippocampus collected simultaneously from 19 patients undergoing temporal lobectomy for treatment of refractory epilepsy. Our findings suggest that total PLA2 activity in platelets may reflect the total activity of the enzyme in the brain (rs=0.59, p=0.008). However in our sample no correlations were found between the subgroups of the enzyme in brain and in platelets. This lack of correlations may be due to different effects of drug treatment on the PLA2 subtypes. In face of the difficulty to obtain brain tissues from living patients, further studies with larger drug-free samples are warranted to clarify whether the use of platelets is a reliable strategy to reflect the subtypes of PLA2 activity in the brain.
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Affiliation(s)
- Leda L Talib
- Laboratory of Neuroscience-LIM 27, Department and Institute of Psychiatry, Faculty of Medicine, University of Sao Paulo, Brazil
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214
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Loucks K, Waddell D, Ross C. Lipopolysaccharides elicit an oxidative burst as a component of the innate immune system in the seagrass Thalassia testudinum. Plant Physiol Biochem 2013; 70:295-303. [PMID: 23807482 DOI: 10.1016/j.plaphy.2013.05.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 05/20/2013] [Indexed: 06/02/2023]
Abstract
This study represents the first report characterizing the biological effects of a lipopolysaccharide (LPS) immune modulator on a marine vascular plant. LPS was shown to serve as a strong elicitor of the early defense response in the subtropical seagrass Thalassia testudinum Banks ex König and was capable of inducing an oxidative burst identified at the single cell level. The formation of reactive oxygen species (ROS), detected by a redox-sensitive fluorescent probe and luminol-based chemiluminescence, included a diphenyleneiodonium sensitive response, suggesting the involvement of an NADPH oxidase. A 900 bp cDNA fragment coding for this enzyme was sequenced and found to encode a NAD binding pocket domain with extensive homology to the Arabidopsis thaliana rbohF (respiratory burst oxidase homolog) gene. The triggered release of ROS occurred at 20 min post-elicitation and was dose-dependent, requiring a minimal threshold of 50 μg/mL LPS. Pharmacological dissection of the early events preceding ROS emission indicated that the signal transduction chain of events involved extracellular alkalinization, G-proteins, phospholipase A2, as well as K(+), Ca(2+), and anion channels. Despite exclusively thriving in a marine environment, seagrasses contain ROS-generating machinery and signal transduction components that appear to be evolutionarily conserved with the well-characterized defense response systems found in terrestrial plants.
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Affiliation(s)
- Kyle Loucks
- Department of Biology, University of North Florida, 1 UNF Drive, Jacksonville, FL 32224, USA
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215
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Romero P, Gandía M, Alférez F. Interplay between ABA and phospholipases A(2) and D in the response of citrus fruit to postharvest dehydration. Plant Physiol Biochem 2013; 70:287-294. [PMID: 23800664 DOI: 10.1016/j.plaphy.2013.06.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 06/01/2013] [Indexed: 06/02/2023]
Abstract
The interplay between abscisic acid (ABA) and phospholipases A2 and D (PLA2 and PLD) in the response of citrus fruit to water stress was investigated during postharvest by using an ABA-deficient mutant from 'Navelate' orange named 'Pinalate'. Fruit from both varieties harvested at two different maturation stages (mature-green and full-mature) were subjected to prolonged water loss inducing stem-end rind breakdown (SERB) in full-mature fruit. Treatment with PLA2 inhibitor aristolochic acid (AT) and PLD inhibitor lysophosphatidylethanolamine (LPE) reduced the disorder in both varieties, suggesting that phospholipid metabolism is involved in citrus peel quality. Expression of CsPLDα and CsPLDβ, and CssPLA2α and CssPLA2β was studied by real-time RT-PCR during water stress and in response to ABA. CsPLDα expression increased in mature-green fruit from 'Navelate' but not in 'Pinalate' and ABA did not counteract this effect. ABA enhanced repression of CsPLDα in full-mature fruit. CsPLDβ gene expression decreased in mature-green 'Pinalate', remained unchanged in 'Navelate' and was induced in full-mature fruit from both varieties. CssPLA2α expression increased in mature-green fruit from both varieties whereas in full-mature fruit only increased in 'Navelate'. CssPLA2β expression increased in mature-green flavedo from both varieties, but in full-mature fruit remained steady in 'Navelate' and barely increased in 'Pinalate' fruit. ABA reduced expression in both after prolonged storage. Responsiveness to ABA increased with maturation. Our results show interplay between PLA2 and PLD and suggest that ABA action is upstream phospholipase activation. Response to ABA during water stress in citrus is regulated during fruit maturation and involves membrane phospholipid degradation.
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Affiliation(s)
- Paco Romero
- Instituto de Agroquímica y Tecnología de Alimentos (IATA), Consejo Superior de Investigaciones Científicas (CSIC), Av. Agustín Escardino, 7, Paterna, Valencia 46980, Spain
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216
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Currò M, Ferlazzo N, Risitano R, Condello S, Vecchio M, Caccamo D, Ientile R. Transglutaminase 2 and phospholipase A₂ interactions in the inflammatory response in human Thp-1 monocytes. Amino Acids 2013; 46:759-66. [PMID: 23913269 DOI: 10.1007/s00726-013-1569-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 07/19/2013] [Indexed: 12/16/2022]
Abstract
Several experimental approaches have demonstrated that transglutaminase 2 (TG2) increased activity is involved in monocyte activation and inflammatory response. Preliminary results also demonstrate a TG-mediated post-translational modification of phospholipase A2 (PLA2), which catalyzes the release of arachidonic acid from its lipid storage sites. The control of PLA2-mediated production of eicosanoids has been found to be of great benefit for inflammatory disease treatment. However, the identification of the mechanisms of PLA2 activation is a very complex issue, because of the presence of multiple PLA2 forms. The aim of this study was to characterize the interactions between TG2 and sPLA2 in LPS-stimulated THP-1 cells, which were treated with TPA to induce early differentiated macrophage-type model. We demonstrated that increases in TG2 enzyme activity and protein expression may be considered an early event in monocyte/macrophage activation by LPS. Under these conditions, TG2 protein was co-immunoprecipitated with PLA2 by monoclonal antibody directed against the secretory form of the enzyme (sPLA2-V). Concomitantly, the PLA2 enzyme activity increased in TPA-treated cells exposed to LPS; these high levels of enzyme activity were significant reduced by R283, a site-specific inhibitor of TG2. Moreover, confocal laser scanning microscopy analysis of double-immunostained cytochemical specimens confirmed a co-localization of BAPA-labeled proteins and sPLA2-V in LPS-treated cells. These findings give evidence of a complex TG2/sPLA2-V, suggesting the possibility that sPLA2-V is a substrate for TG2. These results demonstrated that TG2 increases produced a sustained activation of PLA2 activity, suggesting a functional interaction between these enzymes in the regulation of inflammatory response.
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Affiliation(s)
- Monica Currò
- Department of Biomedical Sciences and Morphological and Functional Imaging, University of Messina, AOU Policlinico "G. Martino", Via C. Valeria, 98125, Messina, Italy
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217
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Jo M, Yun HM, Park KR, Hee Park M, Myoung Kim T, Ho Pak J, Jae Lee S, Moon DC, Park CW, Song S, Lee CK, Bae Han S, Tae Hong J. Lung tumor growth-promoting function of peroxiredoxin 6. Free Radic Biol Med 2013; 61:453-63. [PMID: 23643677 DOI: 10.1016/j.freeradbiomed.2013.04.032] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 04/17/2013] [Accepted: 04/24/2013] [Indexed: 01/05/2023]
Abstract
This study compared lung tumor growth in PRDX6-overexpressing transgenic (Tg) mice and normal mice. These mice expressed elevated levels of PRDX6 mRNA and protein in multiple tissues. In vivo, Tg mice displayed a greater increase in the growth of lung tumor compared with normal mice. Glutathione peroxidase and calcium-independent phospholipase 2 (iPLA2) activities in tumor tissues of Tg mice were much higher than in tumor tissues of normal mice. Higher tumor growth in PRDX6-overexpressing Tg mice was associated with an increase in activating protein-1 (AP-1) DNA-binding activity. Moreover, expression of proliferating cell nuclear antigen, Ki67, vascular endothelial growth factor, c-Jun, c-Fos, metalloproteinase-9, cyclin-dependent kinases, and cyclins was much higher in the tumor tissues of PRDX6-overexpressing Tg mice than in tumor tissues of normal mice. However, the expression of apoptotic regulatory proteins including caspase-3 and Bax was slightly less in the tumor tissues of normal mice. In tumor tissues of PRDX6-overexpressing Tg mice, activation of mitogen-activated protein kinases (MAPKs) was much higher than in normal mice. In cultured lung cancer cells, PRDX6 siRNA suppressed glutathione peroxidase and iPLA2 activities and cancer cell growth, but the enforced overexpression of PRDX6 increased cancer cell growth associated with their increased activities. In vitro, among the tested MAPK inhibitors, c-Jun NH2-terminal kinase (JNK) inhibitor clearly suppressed the growth of lung cancer cells and AP-1 DNA binding, glutathione peroxidase activity, and iPLA2 activity in normal and PRDX6-overexpressing lung cancer cells. These data indicate that overexpression of PRDX6 promotes lung tumor growth via increased glutathione peroxidase and iPLA2 activities through the upregulation of the AP-1 and JNK pathways.
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Affiliation(s)
- Miran Jo
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea
| | - Hyung-Mun Yun
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea
| | - Kyung-Ran Park
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea
| | - Mi Hee Park
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea
| | - Tae Myoung Kim
- College of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, Korea
| | - Jhang Ho Pak
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736, Korea
| | - Soo Jae Lee
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea
| | - Dong Cheul Moon
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea
| | - Chun-Woong Park
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea
| | - Sukgil Song
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea
| | - Chong-Kil Lee
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea
| | - Sang Bae Han
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea
| | - Jin Tae Hong
- College of Pharmacy, Medical Research Center, Cheongju, Chungbuk 361-763, Korea.
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218
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Korbecki J, Baranowska-Bosiacka I, Gutowska I, Chlubek D. The effect of reactive oxygen species on the synthesis of prostanoids from arachidonic acid. J Physiol Pharmacol 2013; 64:409-421. [PMID: 24101387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 08/14/2013] [Indexed: 06/02/2023]
Abstract
Reactive oxygen species (ROS), such as hydrogen peroxide, superoxide anion radical or hydroxyl radical, play an important role in inflammation processes as well as in transduction of signals from receptors to interleukin -1β (IL-1β), tumor necrosis factor α (TNF-α) or lipopolysaccharides (LPS). NADPH oxidase increases the ROS levels, leading to inactivation of protein phosphatase 1 (PP1), protein phosphatase 2A (PP2A) and protein tyrosine phosphatase (PTP): MAPK phosphatase 1 (MKP-1). Inactivation of phosphatases results in activation of mitogen-activated protein kinase (MAPK) cascades: c-Jun N-terminal kinase (JNK), p38 and extracellular signal-regulated kinase (Erk), which, in turn, activate cytosolic phospholipase A₂ (cPLA₂). ROS cause cytoplasmic calcium influx by activation of phospholipase C (PLC) and phosphorylation of IP₃-sensitive calcium channels. ROS activate nuclear factor κB (NF-κB) via IκB kinase (IKK) through phosphoinositide 3-kinase (PI3K), tumor suppressor phosphatase and tensin homolog (PTEN) and protein kinase B (Akt/PKB) or NF-κB-inducing kinase (NIK). IKK phosphorylates NF-κB α subunit (IκBα) at Ser³². Oxidative stress inactivates NIK and IκB kinase γ subunit/NF-κB essential modulator (IKKγ/NEMO), which might cause activation of NF-κB that is independent on IKK and inhibitor of IκBα degradation, including phosphorylation of Tyr⁴² at IκBα by c-Src and spleen tyrosine kinase (Syk), phosphorylation of the domain rich in proline, glutamic acid, serine and threonine (PEST) sequence by casein kinase II and inactivation of protein tyrosine phosphatase 1B (PTP1B). NF-κB and MAPK cascades-activated transcription factor activator protein 1 (AP-1) and CREB-binding protein (CBP/p300) lead to expression of cytosolic phospholipase A₂ (cPLA₂), cyclooxygenase-2 (COX-2) and membrane-bound prostaglandin E synthase 1 (mPGES-1), and thus to increased release of arachidonic acid and production of prostaglandins, particularly prostaglandin E₂ (PGE₂). ROS increase the activity of hematopoietic-type PGD synthase (H-PGDS), and, as a result, the production of prostaglandin D₂ (PGD₂). However, the superoxide radical reacts with nitric oxide forming peroxynitrite that inactivates prostaglandin I synthase (PGIS), suppressing the production of prostaglandin I₂ (PGI₂). ROS do not affect thromboxane synthesis in a direct manner; this is achieved by an increase in cPLA₂ activity and COX-2 expression. The aim of this review was to summarize knowledge of influence of ROS on the synthesis of prostanoids from arachidonic acid.
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Affiliation(s)
- J Korbecki
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University, Szczecin, Poland.
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219
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Ettinger K, Cohen G, Momic T, Lazarovici P. The effects of a chactoid scorpion venom and its purified toxins on rat blood pressure and mast cells histamine release. Toxins (Basel) 2013; 5:1332-42. [PMID: 23899970 PMCID: PMC3760037 DOI: 10.3390/toxins5081332] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Revised: 06/25/2013] [Accepted: 07/18/2013] [Indexed: 01/09/2023] Open
Abstract
The effect of the venom of the Chactoid family of scorpions on blood pressure was scantly investigated and was addressed in the present study using the venom of the Israeli scorpion, Scorpio maurus palmatus. Blood pressure in rats was monitored via cannulated femoral artery, while venom and toxins were introduced into femoral vein. Venom injection elicited a biphasic effect, expressed first by a fast and transient hypotensive response, which lasted up to 10 min, followed by a hypertensive response, which lasted up to one hour. It was found that these effects resulted from different venom components. Phospholipase A2 produced the hypotensive effect, while a non-enzymatic neurotoxic polypeptide fraction produced the hypertensive effect. Surprisingly, the main neurotoxic polypeptide to mice had no effect on blood pressure. In vitro experiments indicated that the hypertensive factors caused histamine release from the peritoneal mast cells, but this effect is assumed to be not relevant to their in vivo effect. In spite of the cytotoxic activity of phospholipase A2, it did not release histamine. These findings suggest that the effects of venom and isolated fractions on blood pressure parameters are mediated by different mechanisms, which deserve further pharmacological investigation.
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Affiliation(s)
| | | | | | - Philip Lazarovici
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +972-2-6758729; Fax: +972-2-6757490
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220
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Elkharaz J, Ugun-Klusek A, Constantin-Teodosiu D, Lawler K, Mayer RJ, Billett E, Lowe J, Bedford L. Implications for oxidative stress and astrocytes following 26S proteasomal depletion in mouse forebrain neurones. Biochim Biophys Acta Mol Basis Dis 2013; 1832:1930-8. [PMID: 23851049 DOI: 10.1016/j.bbadis.2013.07.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 06/25/2013] [Accepted: 07/01/2013] [Indexed: 02/06/2023]
Abstract
Neurodegenerative diseases are characterized by progressive degeneration of selective neurones in the nervous system, but the underlying mechanisms involved in neuroprotection and neurodegeneration remain unclear. Dysfunction of the ubiquitin proteasome system is one of the proposed hypotheses for the cause and progression of neuronal loss. We have performed quantitative two-dimensional fluorescence difference in-gel electrophoresis combined with peptide mass fingerprinting to reveal proteome changes associated with neurodegeneration following 26S proteasomal depletion in mouse forebrain neurones. Differentially expressed proteins were validated by Western blotting, biochemical assays and immunohistochemistry. Of significance was increased expression of the antioxidant enzyme peroxiredoxin 6 (PRDX6) in astrocytes, associated with oxidative stress. Interestingly, PRDX6 is a bifunctional enzyme with antioxidant peroxidase and phospholipase A2 (PLA2) activities. The PLA2 activity of PRDX6 was also increased following 26S proteasomal depletion and may be involved in neuroprotective or neurodegenerative mechanisms. This is the first in vivo report of oxidative stress caused directly by neuronal proteasome dysfunction in the mammalian brain. The results contribute to understanding neuronal-glial interactions in disease pathogenesis, provide an in vivo link between prominent disease hypotheses and importantly, are of relevance to a heterogeneous spectrum of neurodegenerative diseases.
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Affiliation(s)
- Jamal Elkharaz
- School of Biomedical Sciences, University of Nottingham, Nottingham, UK
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221
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Dedieu L, Serveau-Avesque C, Canaan S. Identification of residues involved in substrate specificity and cytotoxicity of two closely related cutinases from Mycobacterium tuberculosis. PLoS One 2013; 8:e66913. [PMID: 23843969 PMCID: PMC3699616 DOI: 10.1371/journal.pone.0066913] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 05/11/2013] [Indexed: 11/20/2022] Open
Abstract
The enzymes belonging to the cutinase family are serine enzymes active on a large panel of substrates such as cutin, triacylglycerols, and phospholipids. In the M. tuberculosis H37Rv genome, seven genes coding for cutinase-like proteins have been identified with strong immunogenic properties suggesting a potential role as vaccine candidates. Two of these enzymes which are secreted and highly homologous, possess distinct substrates specificities. Cfp21 is a lipase and Cut4 is a phospholipase A2, which has cytotoxic effects on macrophages. Structural overlay of their three-dimensional models allowed us to identify three areas involved in the substrate binding process and to shed light on this substrate specificity. By site-directed mutagenesis, residues present in these Cfp21 areas were replaced by residues occurring in Cut4 at the same location. Three mutants acquired phospholipase A1 and A2 activities and the lipase activities of two mutants were 3 and 15 fold greater than the Cfp21 wild type enzyme. In addition, contrary to mutants with enhanced lipase activity, mutants that acquired phospholipase B activities induced macrophage lysis as efficiently as Cut4 which emphasizes the relationship between apparent phospholipase A2 activity and cytotoxicity. Modification of areas involved in substrate specificity, generate recombinant enzymes with higher activity, which may be more immunogenic than the wild type enzymes and could therefore constitute promising candidates for antituberculous vaccine production.
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Affiliation(s)
- Luc Dedieu
- CNRS - Aix-Marseille Université - Enzymologie Interfaciale et Physiologie de la Lipolyse - UMR 7282, Marseille, France
| | - Carole Serveau-Avesque
- CNRS - Aix-Marseille Université - Enzymologie Interfaciale et Physiologie de la Lipolyse - UMR 7282, Marseille, France
| | - Stéphane Canaan
- CNRS - Aix-Marseille Université - Enzymologie Interfaciale et Physiologie de la Lipolyse - UMR 7282, Marseille, France
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222
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Almunia C, Bretaudeau M, Held G, Babon A, Marchetti C, Castelli FA, Ménez A, Maillere B, Gillet D. Bee Venom Phospholipase A2, a Good "Chauffeur" for Delivering Tumor Antigen to the MHC I and MHC II Peptide-Loading Compartments of the Dendritic Cells: The Case of NY-ESO-1. PLoS One 2013; 8:e67645. [PMID: 23825678 PMCID: PMC3688974 DOI: 10.1371/journal.pone.0067645] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 05/20/2013] [Indexed: 12/23/2022] Open
Abstract
Bee venom phospholipase A2 (bvPLA2) is a small, 15kDa enzyme which hydrolyses many phospholipids through interfacial binding. The mutated bvPLA2H34Q (bvPLA2m), in which histidine-34 is replaced by glutamine, is not catalytically active. This protein has been shown to be a suitable membrane anchor and has been suggested as a suitable tumor-antigen vector for the development of novel dendritic cell-based vaccines. To confirm this feature, in this study the fusion protein PNY, composed of NY-ESO-1(NY(s)) fused to the C-terminus of bvPLA2m, was engineered. bvPLA2m enhanced the binding of NY(s) to the membrane of human monocyte-derived dendritic cells (DCs) and, once taken up by the cells, the antigen fused to the vector was directed to both MHC I and MHC II peptide-loading compartments. bvPLA2m was shown to increase the cross-presentation of the NY(s)-derived, restricted HLA-A*02 peptide, NY-ESO-1157-165(NY157-165), at the T1 cell surface. DCs loaded with the fusion protein induced cross-priming of NY(s)-specific CD8 + T-cells with greater efficiency than DCs loaded with NY(s). Sixty-five percent of these NY(s)-specific CD8+ T-cell lines could also be activated with the DCs pulsed with the peptide, NY157-165. Of these CD8+ T-cell lines, two were able to recognize the human melanoma cell line, SK-MEL-37, in a context of HLA-A*02. Only a small number of bvPLA2m CD8+ T-cell lines were induced, indicating the low immunogenicity of the protein. It was concluded that bvPLA2m can be used as a membrane-binding vector to promote MHC class II peptide presentation and MHC class I peptide cross-presentation. Such a system can, therefore, be tested for the preparation of cell-based vaccines.
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Affiliation(s)
- Christine Almunia
- Service d’Ingénierie Moléculaire des Protéines, Institut de Biologie et Technologies de Saclay, Commissariat à l'énergie atomique et aux énergies alternatives, Gif Sur Yvette, France
- Service de Biochimie et de Toxicologie nucléaire, Institut de Biologie Environnementale et Biotechnologie, Commissariat à l'énergie atomique et aux énergies alternatives, Bagnols sur Cèze, France
| | - Marie Bretaudeau
- Service de Biochimie et de Toxicologie nucléaire, Institut de Biologie Environnementale et Biotechnologie, Commissariat à l'énergie atomique et aux énergies alternatives, Bagnols sur Cèze, France
| | - Gerhard Held
- Medizinische Klinik I, Universitaetsklinik des Saarlandes, Homburg, Germany
| | - Aurélie Babon
- Service d’Ingénierie Moléculaire des Protéines, Institut de Biologie et Technologies de Saclay, Commissariat à l'énergie atomique et aux énergies alternatives, Gif Sur Yvette, France
| | - Charles Marchetti
- Service de Biochimie et de Toxicologie nucléaire, Institut de Biologie Environnementale et Biotechnologie, Commissariat à l'énergie atomique et aux énergies alternatives, Bagnols sur Cèze, France
| | - Florence Anne Castelli
- Service d’Ingénierie Moléculaire des Protéines, Institut de Biologie et Technologies de Saclay, Commissariat à l'énergie atomique et aux énergies alternatives, Gif Sur Yvette, France
| | - André Ménez
- Service d’Ingénierie Moléculaire des Protéines, Institut de Biologie et Technologies de Saclay, Commissariat à l'énergie atomique et aux énergies alternatives, Gif Sur Yvette, France
- Museum National d'Histoire Naturelle, Paris, France
| | - Bernard Maillere
- Service d’Ingénierie Moléculaire des Protéines, Institut de Biologie et Technologies de Saclay, Commissariat à l'énergie atomique et aux énergies alternatives, Gif Sur Yvette, France
| | - Daniel Gillet
- Service d’Ingénierie Moléculaire des Protéines, Institut de Biologie et Technologies de Saclay, Commissariat à l'énergie atomique et aux énergies alternatives, Gif Sur Yvette, France
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Yun HM, Jin P, Han JY, Lee MS, Han SB, Oh KW, Hong SH, Jung EY, Hong JT. Acceleration of the development of Alzheimer's disease in amyloid beta-infused peroxiredoxin 6 overexpression transgenic mice. Mol Neurobiol 2013; 48:941-51. [PMID: 23771816 DOI: 10.1007/s12035-013-8479-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Accepted: 05/30/2013] [Indexed: 11/25/2022]
Abstract
The amyloid beta (Aβ) peptide in the brains of patients with Alzheimer's disease (AD) is cytotoxic to neurons and has a central role in the pathogenesis of the disease. Peroxiredoxin 6 (Prdx6) is an antioxidant protein and could act as a cytoprotective protein. However, the role of Prdx6 in neurodegenerative disease has not been studied. Thus, the roles and action mechanisms in the development of AD were examined. Aβ1-42-induced memory impairment in Prdx6 transgenic mice was worse than C57BL/6 mice, and the expression of amyloid precursor protein cleavage, C99, β-site APP-cleaving enzyme 1, inducible nitric oxide synthase, and cyclooxygenase-2 was greatly increased. In addition, the astrocytes and microglia cells of Aβ-infused Prdx6 transgenic mice were more activated, and Aβ also significantly increased lipid peroxidation and protein carbonyl levels, but decreased glutathione levels. Furthermore, we found that translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) to the nucleus was increased in Aβ-infused Prdx6 transgenic mice. These results suggest that the overexpression of Prdx6 could accelerate the development of AD through increased amyloidogenesis through independent PLA2 activation and Nrf2 transcription.
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Affiliation(s)
- Hyung-Mun Yun
- College of Pharmacy and Medical Research Center, Chungbuk National University, 12 Gaesin-dong, Heungduk-gu, Cheongju, Chungbuk, 361-763, South Korea
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Callaghan CM, Johnson A, Neumann P, Leggett RE, Schuler C, Levin RM. The effect of partial outlet obstruction on calpain and phospholipase-2 activities: analyzed by severity and duration. Mol Cell Biochem 2013; 381:217-20. [PMID: 23737136 DOI: 10.1007/s11010-013-1705-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2013] [Accepted: 05/24/2013] [Indexed: 12/23/2022]
Abstract
In an attempt to better understand the two pathways that lead to bladder decompensation following partial obstruction in rabbits one of which is caused by calcium-activated enzymes and the other by oxidative stress, calpain and phospholipase A2 (PLA2) biochemical assays were conducted to see how bladder decompensation is mediated by these two calcium-activated enzymes. Partial outlet obstructions of varying durations (4, 8, and 12 weeks plus controls) were performed on 32 New Zealand white rabbits. The rabbits were also grouped by severity: control, mild, intermediate, and severe. The activities of Calpain and PLA2 on the muscle tissue of the bladders were analyzed. A stronger correlation was seen between activities and severities as opposed to between activities and durations for both PLA2 and calpain. The activity for PLA2 increased dramatically from control to mild and then stayed constant for both intermediate and severe obstructions. Calpain activity increased steadily from control to mild to intermediate to severe. Based on the increase in levels of the calcium-dependent enzymes, it was clearly shown that calcium levels increased in all stages of bladder decompensation most notably with the mild obstructions. Based on previous studies in which nitrotyrosine and dinitrophenol levels did not increase in mildly obstructed rabbits, the calcium overload pathway may predominate in mild decompensation because cells in mildly obstructed bladders are better able to cope with oxidative stress than increased calcium levels.
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Affiliation(s)
- Connor M Callaghan
- Pharmacy Practice, Albany College of Pharmacy and Health Sciences, Albany, NY 12208, USA
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225
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Almilaji A, Szteyn K, Fein E, Pakladok T, Munoz C, Elvira B, Towhid ST, Alesutan I, Shumilina E, Bock CT, Kandolf R, Lang F. Down-regulation of Na/K+ atpase activity by human parvovirus B19 capsid protein VP1. Cell Physiol Biochem 2013; 31:638-648. [PMID: 23689698 DOI: 10.1159/000350083] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/23/2013] [Indexed: 10/09/2023] Open
Abstract
BACKGROUND/AIMS Human parvovirus B19 (B19V) may cause inflammatory cardiomyopathy (iCMP) which is accompanied by endothelial dysfunction. The B19V capsid protein VP1 contains a lysophosphatidylcholine producing phospholipase A2 (PLA) sequence. Lysophosphatidylcholine has in turn been shown to inhibit Na(+)/K(+) ATPase. The present study explored whether VP1 modifies Na(+)/K(+) ATPase activity. METHODS Xenopus oocytes were injected with cRNA encoding VP1 isolated from a patient suffering from fatal B19V-iCMP or cRNA encoding PLA2-negative VP1 mutant (H153A) and K(+) induced pump current (I(pump)) as well as ouabain-inhibited current (I(ouabain)) both reflecting Na(+)/K(+)-ATPase activity were determined by dual electrode voltage clamp. RESULTS Injection of cRNA encoding VP1, but not of VP1(H153A) or water, was followed by a significant decrease of both, I(pump) and I(ouabain) in Xenopus oocytes. The effect was not modified by inhibition of transcription with actinomycin (10 µM for 36 hours) but was abrogated in the presence of PLA2 specific blocker 4-bromophenacylbromide (50 µM) and was mimicked by lysophosphatidylcholine (0.5 - 1 µg/ml). According to whole cell patch clamp, lysophosphatidylcholine (1 µg /ml) similarly decreased I(pump) in human microvascular endothelial cells (HMEC). CONCLUSION The B19V capsid protein VP1 is a powerful inhibitor of host cell Na(+)/K(+) ATPase, an effect at least partially due to phospholipase A2 (PLA2) dependent formation of lysophosphatidylcholine.
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Affiliation(s)
- Ahmad Almilaji
- Department of Physiology, University of Tübingen, Tübingen, Germany
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226
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Pirman DA, Efuet E, Ding XP, Pan Y, Tan L, Fischer SM, DuBois RN, Yang P. Changes in cancer cell metabolism revealed by direct sample analysis with MALDI mass spectrometry. PLoS One 2013; 8:e61379. [PMID: 23658609 PMCID: PMC3637300 DOI: 10.1371/journal.pone.0061379] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 03/08/2013] [Indexed: 02/06/2023] Open
Abstract
Biomarker discovery using mass spectrometry (MS) has recently seen a significant increase in applications, mainly driven by the rapidly advancing field of metabolomics. Instrumental and data handling advancements have allowed for untargeted metabolite analyses which simultaneously interrogate multiple biochemical pathways to elucidate disease phenotypes and therapeutic mechanisms. Although most MS-based metabolomic approaches are coupled with liquid chromatography, a few recently published studies used matrix-assisted laser desorption (MALDI), allowing for rapid and direct sample analysis with minimal sample preparation. We and others have reported that prostaglandin E3 (PGE3), derived from COX-2 metabolism of the omega-3 fatty acid eicosapentaenoic acid (EPA), inhibited the proliferation of human lung, colon and pancreatic cancer cells. However, how PGE3 metabolism is regulated in cancer cells, particularly human non-small cell lung cancer (NSCLC) cells, is not fully understood. Here, we successfully used MALDI to identify differences in lipid metabolism between two human non-small-cell lung cancer (NSCLC) cell lines, A549 and H596, which could contribute to their differential response to EPA treatment. Analysis by MALDI-MS showed that the level of EPA incorporated into phospholipids in H596 cells was 4-fold higher than A549 cells. Intriguingly, H596 cells produced much less PGE3 than A549 cells even though the expression of COX-2 was similar in these two cell lines. This appears to be due to the relatively lower expression of cytosolic phospholipase A2 (cPLA2) in H596 cells than that of A549 cells. Additionally, the MALDI-MS approach was successfully used on tumor tissue extracts from a K-ras transgenic mouse model of lung cancer to enhance our understanding of the mechanism of action of EPA in the in vivo model. These results highlight the utility of combining a metabolomics workflow with MALDI-MS to identify the biomarkers that may regulate the metabolism of omega-3 fatty acids and ultimately affect their therapeutic potentials.
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Affiliation(s)
- David A. Pirman
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Ekem Efuet
- Department of General Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Xiao-Ping Ding
- Department of General Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Yong Pan
- Department of General Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Lin Tan
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Susan M. Fischer
- Department of Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Raymond N. DuBois
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Peiying Yang
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Department of General Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- * E-mail:
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227
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Liu R, Yang Y, Li Y, Li J, Ma Q, Zhao Y, Wang D. Effects of sevoflurane on pulmonary cytosolic phospholipase A₂ and clara cell secretory protein expressions in rabbits with one-lung ventilation-induced lung injury. Nan Fang Yi Ke Da Xue Xue Bao 2013; 33:469-473. [PMID: 23644101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
OBJECTIVE To investigate the effects of sevoflurane on cytosolic phospholipase A₂ (C-PLA₂) and clara cell secretory protein (CCSP) in lung tissues of rabbits with one-lung ventilation (OLV)-induced lung injuries. METHODS Thirty-six healthy Japanese white rabbits were randomized into sham-operated group, OLV group, and OLV plus sevoflurane group subdivided into 4 subgroups with sevoflurane concentrations of 1%, 2%, 3% and 4%. CCSP and C-PLA₂ mRNA and protein expressions in rabbit lung tissues were detected by Western blotting and real-time PCR, and the content of arachidonic acid (AA) was measured using ELISA. The severities of the lung injury were evaluated according to lung wet/dry weight (W/D) ratio and histological scores. RESULTS In the OLV group and OLV+ sevoflurane groups, pulmonary CCSP expressions were significantly lower, while C-PLA₂ expression, lung W/D ratios and lung histological scores were significantly higher than those in the sham-operated group (P<0.05). Compared with OLV group, the OLV+sevoflurane groups showed significantly increased expressions of CCSP and reduced C-PLA₂ expression, lung W/D ratios and histological scores (P<0.05). In the 4 OLV+sevoflurane groups, CCSP expressions underwent no significant changes as sevoflurane concentration increased, but C-PLA₂ expressions, lung W/D ratios and histological scores all decreased gradually as the concentrations of sevoflurane increased (P<0.05). CONCLUSION OLV can result in down-regulated CCSP expressions and up-regulated C-PLA₂ expressions in rabbit lung tissues. Sevoflurane can protect against OLV-induced acute lung injury possibly by inhibiting C-PLA₂ expression via up-regulation of CCSP expressions or through other mechanisms resulting in down-regulated expression of C-PLA₂.
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Affiliation(s)
- Rui Liu
- School of Pharmacy and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming 650031, China.
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228
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Jiang D, Zheng D, Wang L, Huang Y, Liu H, Xu L, Liao Q, Liu P, Shi X, Wang Z, Sun L, Zhou Q, Li N, Xu L, Le Y, Ye M, Shao G, Duan S. Elevated PLA2G7 gene promoter methylation as a gender-specific marker of aging increases the risk of coronary heart disease in females. PLoS One 2013; 8:e59752. [PMID: 23555769 PMCID: PMC3610900 DOI: 10.1371/journal.pone.0059752] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 02/18/2013] [Indexed: 12/22/2022] Open
Abstract
PLA2G7 gene product is a secreted enzyme whose activity is associated with coronary heart disease (CHD). The goal of our study is to investigate the contribution of PLA2G7 promoter DNA methylation to the risk of CHD. Using the bisulphite pyrosequencing technology, PLA2G7 methylation was measured among 36 CHD cases and 36 well-matched controls. Our results indicated that there was a significant association between PLA2G7 methylation and CHD (adjusted P = 0.025). Significant gender-specific correlation was observed between age and PLA2G7 methylation (males: adjusted r = −0.365, adjusted P = 0.037; females: adjusted r = 0.373, adjusted P = 0.035). A breakdown analysis by gender showed that PLA2G7 methylation was significantly associated with CHD in females (adjusted P = 0.003) but not in males. A further two-way ANOVA analysis showed there was a significant interaction between gender and status of CHD for PLA2G7 methylation (gender*CHD: P = 6.04E−7). Moreover, PLA2G7 methylation is associated with the levels of total cholesterols (TC, r = 0.462, P = 0.009), triglyceride (TG, r = 0.414, P = 0.02) and Apolipoprotein B (ApoB, r = 0.396, P = 0.028) in females but not in males (adjusted P>0.4). Receiver operating characteristic (ROC) curves showed that PLA2G7 methylation could predict the risk of CHD in females (area under curve (AUC) = 0.912, P = 2.40E−5). Our results suggest that PLA2G7 methylation changes with aging in a gender-specific pattern. The correlation between PLA2G7 methylation and CHD risk in females is independent of other parameters including age, smoking, diabetes and hypertension. PLA2G7 methylation might exert its effects on the risk of CHD by regulating the levels of TC, TG, and ApoB in females. The gender disparities in the PLA2G7 methylation may play a role in the molecular mechanisms underlying the pathophysiology of CHD.
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Affiliation(s)
- Danjie Jiang
- Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
- The Affiliated Hospital, Ningbo University, Ningbo, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University, Ningbo, Zhejiang, China
| | - Dawei Zheng
- Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
| | - Lingyan Wang
- Bank of Blood Products, Ningbo No.2 Hospital, Ningbo, Zhejiang, China
| | - Yi Huang
- The Affiliated Hospital, Ningbo University, Ningbo, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University, Ningbo, Zhejiang, China
| | - Haibo Liu
- Yinzhou People’s Hospital, Ningbo University, Ningbo, Zhejiang, China
| | - Leiting Xu
- The Affiliated Hospital, Ningbo University, Ningbo, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University, Ningbo, Zhejiang, China
| | - Qi Liao
- The Affiliated Hospital, Ningbo University, Ningbo, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University, Ningbo, Zhejiang, China
| | - Panpan Liu
- The Affiliated Hospital, Ningbo University, Ningbo, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University, Ningbo, Zhejiang, China
| | - Xinbao Shi
- Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
| | - Zhaoyang Wang
- Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
| | - Lebo Sun
- Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
| | - Qingyun Zhou
- Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
| | - Ni Li
- Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
| | - Limin Xu
- The Affiliated Hospital, Ningbo University, Ningbo, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University, Ningbo, Zhejiang, China
| | - Yanping Le
- The Affiliated Hospital, Ningbo University, Ningbo, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University, Ningbo, Zhejiang, China
| | - Meng Ye
- The Affiliated Hospital, Ningbo University, Ningbo, Zhejiang, China
- * E-mail: (SD); (GS); (MY)
| | - Guofeng Shao
- Ningbo Medical Center Lihuili Hospital, Ningbo University, Ningbo, Zhejiang, China
- * E-mail: (SD); (GS); (MY)
| | - Shiwei Duan
- The Affiliated Hospital, Ningbo University, Ningbo, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University, Ningbo, Zhejiang, China
- * E-mail: (SD); (GS); (MY)
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Abstract
Cardiolipin, a major component of mitochondria, is critical for mitochondrial functioning including the regulation of cytochrome c release during apoptosis and proper electron transport. Mitochondrial cardiolipin with its unique bulky amphipathic structure is a potential substrate for phospholipase A2 (PLA2) in vivo. We have developed mass spectrometric methodology for analyzing PLA2 activity toward various cardiolipin forms and demonstrate that cardiolipin is a substrate for sPLA2, cPLA2 and iPLA2, but not for Lp-PLA2. Our results also show that none of these PLA2s have significant PLA1 activities toward dilyso-cardiolipin. To understand the mechanism of cardiolipin hydrolysis by PLA2, we also quantified the release of monolyso-cardiolipin and dilyso-cardiolipin in the PLA2 assays. The sPLA2s caused an accumulation of dilyso-cardiolipin, in contrast to iPLA2 which caused an accumulation of monolyso-cardiolipin. Moreover, cardiolipin inhibits iPLA2 and cPLA2, and activates sPLA2 at low mol fractions in mixed micelles of Triton X-100 with the substrate 1-palmitoyl-2-arachidonyl-sn-phosphtidylcholine. Thus, cardiolipin functions as both a substrate and a regulator of PLA2 activity and the ability to assay the various forms of PLA2 is important in understanding its function.
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Affiliation(s)
- Yuan-Hao Hsu
- Department of Chemistry, Tunghai University, Taichung, Taiwan
- Department of Pharmacology, University of California San Diego, La Jolla, California, United States of America
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, United States of America
- * E-mail: (EAD); (YHH)
| | - Darren S. Dumlao
- Department of Pharmacology, University of California San Diego, La Jolla, California, United States of America
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, United States of America
| | - Jian Cao
- Department of Pharmacology, University of California San Diego, La Jolla, California, United States of America
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, United States of America
| | - Edward A. Dennis
- Department of Pharmacology, University of California San Diego, La Jolla, California, United States of America
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, United States of America
- * E-mail: (EAD); (YHH)
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230
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De Smet CH, Cox R, Brouwers JF, de Kroon AIPM. Yeast cells accumulate excess endogenous palmitate in phosphatidylcholine by acyl chain remodeling involving the phospholipase B Plb1p. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1167-76. [PMID: 23501167 DOI: 10.1016/j.bbalip.2013.03.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 03/01/2013] [Accepted: 03/04/2013] [Indexed: 11/18/2022]
Abstract
In the yeast Saccharomyces cerevisiae, the molecular species profile of the major membrane glycerophospholipid phosphatidylcholine (PC) is determined by the molecular species-selectivity of the biosynthesis routes and by acyl chain remodeling. Overexpression of the glycerol-3-phosphate acyltransferase Sct1p was recently shown to induce a strong increase in the cellular content of palmitate (C16:0). Using stable isotope labeling and mass spectrometry, the present study shows that wild type yeast overexpressing Sct1p incorporates excess C16:0 into PC via the methylation of PE, the CDP-choline route, and post-synthetic acyl chain remodeling. Overexpression of Sct1p increased the extent of remodeling of PE-derived PC, providing a novel tool to perform mechanistic studies on PC acyl chain exchange. The exchange of acyl chains occurred at both the sn-1 and sn-2 positions of the glycerol backbone of PC, and required the phospholipase B Plb1p for optimal efficiency. Sct1p-catalyzed acyl chain exchange, the acyl-CoA binding protein Acb1p, the Plb1p homologue Plb2p, and the glycerophospholipid:triacylglycerol transacylase Lro1p were not required for PC remodeling. The results indicate that PC serves as a buffer for excess cellular C16:0.
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231
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Massoner P, Kugler KG, Unterberger K, Kuner R, Mueller LAJ, Fälth M, Schäfer G, Seifarth C, Ecker S, Verdorfer I, Graber A, Sültmann H, Klocker H. Characterization of transcriptional changes in ERG rearrangement-positive prostate cancer identifies the regulation of metabolic sensors such as neuropeptide Y. PLoS One 2013; 8:e55207. [PMID: 23390522 PMCID: PMC3563644 DOI: 10.1371/journal.pone.0055207] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 12/27/2012] [Indexed: 12/15/2022] Open
Abstract
ERG gene rearrangements are found in about one half of all prostate cancers. Functional analyses do not fully explain the selective pressure causing ERG rearrangement during the development of prostate cancer. To identify transcriptional changes in prostate cancer, including tumors with ERG gene rearrangements, we performed a meta-analysis on published gene expression data followed by validations on mRNA and protein levels as well as first functional investigations. Eight expression studies (n = 561) on human prostate tissues were included in the meta-analysis. Transcriptional changes between prostate cancer and non-cancerous prostate, as well as ERG rearrangement-positive (ERG+) and ERG rearrangement-negative (ERG−) prostate cancer, were analyzed. Detailed results can be accessed through an online database. We validated our meta-analysis using data from our own independent microarray study (n = 57). 84% and 49% (fold-change>2 and >1.5, respectively) of all transcriptional changes between ERG+ and ERG− prostate cancer determined by meta-analysis were verified in the validation study. Selected targets were confirmed by immunohistochemistry: NPY and PLA2G7 (up-regulated in ERG+ cancers), and AZGP1 and TFF3 (down-regulated in ERG+ cancers). First functional investigations for one of the most prominent ERG rearrangement-associated genes - neuropeptide Y (NPY) - revealed increased glucose uptake in vitro indicating the potential role of NPY in regulating cellular metabolism. In summary, we found robust population-independent transcriptional changes in prostate cancer and first signs of ERG rearrangements inducing metabolic changes in cancer cells by activating major metabolic signaling molecules like NPY. Our study indicates that metabolic changes possibly contribute to the selective pressure favoring ERG rearrangements in prostate cancer.
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Affiliation(s)
- Petra Massoner
- Division of Experimental Urology, Department of Urology, Innsbruck Medical University, Innsbruck, Austria
- Oncotyrol, Center for Personalized Cancer Medicine GmbH, Innsbruck, Austria
- * E-mail: (PM); (HK)
| | - Karl G. Kugler
- Institute for Bioinformatics and Translational Research, University for Health Sciences, Medical Informatics and Technology (UMIT), Hall in Tirol, Austria
| | - Karin Unterberger
- Oncotyrol, Center for Personalized Cancer Medicine GmbH, Innsbruck, Austria
| | - Ruprecht Kuner
- Unit Cancer Genome Research, Division of Molecular Genetics, German Cancer Research Center and National Center of Tumor Diseases, Heidelberg, Germany
| | - Laurin A. J. Mueller
- Institute for Bioinformatics and Translational Research, University for Health Sciences, Medical Informatics and Technology (UMIT), Hall in Tirol, Austria
| | - Maria Fälth
- Unit Cancer Genome Research, Division of Molecular Genetics, German Cancer Research Center and National Center of Tumor Diseases, Heidelberg, Germany
| | - Georg Schäfer
- Division of Experimental Urology, Department of Urology, Innsbruck Medical University, Innsbruck, Austria
| | - Christof Seifarth
- Division of Experimental Urology, Department of Urology, Innsbruck Medical University, Innsbruck, Austria
| | - Simone Ecker
- Institute for Bioinformatics and Translational Research, University for Health Sciences, Medical Informatics and Technology (UMIT), Hall in Tirol, Austria
| | - Irmgard Verdorfer
- Division of Human Genetics, Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, Innsbruck, Austria
| | - Armin Graber
- Institute for Bioinformatics and Translational Research, University for Health Sciences, Medical Informatics and Technology (UMIT), Hall in Tirol, Austria
| | - Holger Sültmann
- Unit Cancer Genome Research, Division of Molecular Genetics, German Cancer Research Center and National Center of Tumor Diseases, Heidelberg, Germany
| | - Helmut Klocker
- Division of Experimental Urology, Department of Urology, Innsbruck Medical University, Innsbruck, Austria
- Oncotyrol, Center for Personalized Cancer Medicine GmbH, Innsbruck, Austria
- * E-mail: (PM); (HK)
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232
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Trono D, Soccio M, Laus MN, Pastore D. The existence of phospholipase A(2) activity in plant mitochondria and its activation by hyperosmotic stress in durum wheat (Triticum durum Desf.). Plant Sci 2013; 199-200:91-102. [PMID: 23265322 DOI: 10.1016/j.plantsci.2012.11.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 11/09/2012] [Accepted: 11/10/2012] [Indexed: 05/19/2023]
Abstract
The activity of mitochondrial phospholipase A(2) (PLA(2)) was shown for the first time in plants. It was observed in etiolated seedlings from durum wheat, barley, tomato, spelt and green seedlings of maize, but not in potato and topinambur tubers and lentil etiolated seedlings. This result was achieved by a novel spectrophotometric assay based on the coupled PLA(2)/lipoxygenase reactions using 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphatidylcholine as substrate; the mitochondrial localisation was assessed by checking recovery of marker enzymes. Durum wheat mitochondrial PLA(2) (DWM-PLA(2)) showed maximal activity at pH 9.0 and 1mM Ca(2+), hyperbolic kinetics (K(m)=90±6μM, V(max)=29±1nmolmin(-1)mg(-1) of protein) and inhibition by methyl arachidonyl fluorophosphonate, 5-(4-benzyloxyphenyl)-4S-(7-phenylheptanoylamino)pentanoic acid and palmityl trifluoromethyl ketone. Reactive oxygen species had no effect on DWM-PLA(2), that instead was activated by about 50% and 95%, respectively, under salt (0.21M NaCl) and osmotic (0.42M mannitol) stress imposed during germination. Contrarily, a secondary Ca(2+)-independent activity, having optimum at pH 7.0, was stress-insensitive. We propose that the activation of DWM-PLA(2) is responsible for the strong increase of free fatty acids recently measured in mitochondria under the same stress conditions [Laus, et al., J. Exp. Bot. 62 (2011) 141-154] that, in turn, activate potassium channel and uncoupling protein, able to counteract hyperosmotic stress.
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Affiliation(s)
- Daniela Trono
- Consiglio per la Ricerca e la sperimentazione in Agricoltura - Centro di Ricerca per la Cerealicoltura, Foggia, Italy
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233
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Abstract
Melatonin is a highly evolutionary conserved endogenous molecule that is mainly produced by the pineal gland, but also by other nonendocrine organs, of most mammals including man. In the recent years, a variety of anti-inflammatory and antioxidant effects have been observed when melatonin is applied exogenously under both in vivo and in vitro conditions. A number of studies suggest that this indole may exert its anti-inflammatory effects through the regulation of different molecular pathways. It has been documented that melatonin inhibits the expression of the isoforms of inducible nitric oxide synthase and cyclooxygenase and limits the production of excessive amounts of nitric oxide, prostanoids, and leukotrienes, as well as other mediators of the inflammatory process such as cytokines, chemokines, and adhesion molecules. Melatonin's anti-inflammatory effects are related to the modulation of a number of transcription factors such as nuclear factor kappa B, hypoxia-inducible factor, nuclear factor erythroid 2-related factor 2, and others. Melatonin's effects on the DNA-binding capacity of transcription factors may be regulated through the inhibition of protein kinases involved in signal transduction, such as mitogen-activated protein kinases. This review summarizes recent research data focusing on the modulation of the expression of different inflammatory mediators by melatonin and the effects on cell signaling pathways responsible for the indole's anti-inflammatory activity. Although there are a numerous published reports that have analyzed melatonin's anti-inflammatory properties, further studies are necessary to elucidate its complex regulatory mechanisms in different cellular types and tissues.
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Affiliation(s)
- José L Mauriz
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) and Institute of Biomedicine, University of León, León, Spain Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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234
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Penrod LV, Allen RE, Turner JL, Limesand SW, Arns MJ. Effects of oxytocin, lipopolysaccharide (LPS), and polyunsaturated fatty acids on prostaglandin secretion and gene expression in equine endometrial explant cultures. Domest Anim Endocrinol 2013; 44:46-55. [PMID: 23063410 DOI: 10.1016/j.domaniend.2012.09.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 09/05/2012] [Accepted: 09/09/2012] [Indexed: 11/28/2022]
Abstract
Increased secretion of prostaglandin F(2)α (PGF(2)α) within the uterus because of uterine inflammation can cause luteolysis and result in early embryonic loss. Supplementation with polyunsaturated fatty acids (PUFAs) has been shown to influence PG production in many species, although the effects on the mare remain unknown. The present study aimed to determine fatty acid uptake in equine endometrial explants and evaluate their influence on PG secretion and expression of enzymes involved in PG synthesis in vitro. Equine endometrial explants were treated with 100 μM arachidonic acid, eicosapentaenoic acid, or docosahexaenoic acid and then challenged with oxytocin (250 nM) or lipopolysaccharide (LPS; 1 μg/mL). Production of PGF(2)α and PG E(2) (PGE(2)) was measured, and mRNA expression of enzymes involved in PG synthesis was determined with quantitative real-time PCR. Media concentrations of PGF(2)α and PGE(2) were higher (P < 0.0001) from endometrial explants challenged with oxytocin or LPS compared with controls despite which fatty acid was added. Only DHA lowered (P < 0.0001) media concentrations of PGF(2)α and PGE(2) from explants. Endometrial explants stimulated with oxytocin had increased expression of PG-endoperoxide synthase 1 (PTGS1; P < 0.02), PG-endoperoxide synthase 2 (PTGS2; P < 0.001), PG F(2)α synthase (PGFS; P < 0.01), PG E(2) synthase (PGES; P < 0.01), and phospholipase A(2) (PLA(2); P < 0.005) compared with controls and regardless of fatty acid treatment; whereas stimulation with LPS increased expression of PTGS2 (P < 0.004), PGFS (P < 0.03), PGES (P < 0.01), and PLA(2) (P < 0.01) compared with controls and regardless of fatty acid treatment. Treatment with PUFAs, specifically DHA, can influence PG secretion in vitro through mechanisms other than enzyme expression.
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Affiliation(s)
- L V Penrod
- Department of Animal Sciences, The University of Arizona, Tucson, Arizona 85721, USA.
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Rapoport SI. Translational studies on regulation of brain docosahexaenoic acid (DHA) metabolism in vivo. Prostaglandins Leukot Essent Fatty Acids 2013; 88:79-85. [PMID: 22766388 PMCID: PMC3467358 DOI: 10.1016/j.plefa.2012.05.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2012] [Revised: 04/29/2012] [Accepted: 05/01/2012] [Indexed: 01/30/2023]
Abstract
One goal in the field of brain polyunsaturated fatty acid (PUFA) metabolism is to translate the many studies that have been conducted in vitro and in animal models to the clinical setting. Doing so should elucidate the role of PUFAs in the human brain, and effects of diet, drugs, disease and genetics on this role. This review discusses new in vivo radiotracer kinetic and neuroimaging techniques that allow us to do this, with a focus on docosahexaenoic acid (DHA). We illustrate how brain PUFA metabolism is influenced by graded reductions in dietary n-3 PUFA content in unanesthetized rats. We also show how kinetic tracer techniques in rodents have helped to identify mechanisms of action of mood stabilizers used in bipolar disorder, how DHA participates in neurotransmission, and how brain DHA metabolism is regulated by calcium-independent iPLA₂β. In humans, regional rates of brain DHA metabolism can be quantitatively imaged with positron emission tomography following intravenous injection of [1-¹¹C]DHA.
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Affiliation(s)
- Stanley I Rapoport
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Building 9, Room 1S128, Bethesda, MD 20892, USA.
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Kravtsov II, Kicherova OA. [The membrane stabilizing effect of glatiramer acetate in multiple sclerosis]. Zh Nevrol Psikhiatr Im S S Korsakova 2013; 113:69-71. [PMID: 23612414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The effect of glatiramer acetate on the structure of the lipid phase of cell membranes of red blood cells, the status of lipid peroxidation and antioxidant defense system in patients with relapsing forms of multiple sclerosis. It is shown that during treatment with glatiramer acetate reduces the initially high, level of phospholipase A2, and the concentration of lipid peroxidation products - diene conjugates and Schiff bases. At the same time against the increase initially reduced activity of the antioxidant defense normal structure of erythrocyte membranes in patients with relapsing-remitting multiple sclerosis. Based on the analysis of the dynamics of laboratory parameters proved membranoprotektiv effect the drug.
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Björnsdottir H, Granfeldt D, Welin A, Bylund J, Karlsson A. Inhibition of phospholipase A(2) abrogates intracellular processing of NADPH-oxidase derived reactive oxygen species in human neutrophils. Exp Cell Res 2012; 319:761-74. [PMID: 23274527 DOI: 10.1016/j.yexcr.2012.12.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 12/10/2012] [Accepted: 12/11/2012] [Indexed: 11/19/2022]
Abstract
Upon activation of human neutrophils, superoxide can be produced at two cellular sites; either in the plasma membrane, giving extracellular release of oxidants, or in intracellular organelles, resulting in oxidants being retained in the cell. The involvement of phospholipase A(2) (PLA(2)) in phorbol myristate acetate (PMA)-induced activation of the two pools of NADPH-oxidase was investigated using a variety of PLA(2) inhibitors and the oxidase activity was measured by luminol/isoluminol-amplified chemiluminescence (CL). Two of the seven inhibitors were without effect, two inhibitors inhibited both intra- and extracellular ROS production equally, and three inhibitors inhibited intracellular but not extracellular CL. Using another technique to measure ROS, PHPA oxidation, we found that intracellular ROS production was unaltered with the three last inhibitors, indicating that PLA(2) is not involved in the NADPH-oxidase activity per se, but in the intracellular processing of the radicals necessary for the CL reaction to take place. The PLA(2) inhibitors did not abolish the activity of myeloperoxidase (MPO), an enzyme necessary for intracellular CL to occur. Instead, we suggest that these PLA(2) inhibitors block heterotypic granule fusion and prohibit the colocalization of ROS and MPO needed for intracellular CL activity.
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Affiliation(s)
- Halla Björnsdottir
- The Phagocyte Research Laboratory, Department of Rheumatology and Inflammation Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg 41346, Sweden.
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Abstract
OBJECTIVES Intestinal dysmotility is one of the effects of cystic fibrosis (CF), but when and how this develops is not well understood. The goal of the present study was to use the Cftr knockout mouse to determine when in development circular smooth muscle of the small intestine becomes dysfunctional. METHODS Wild-type (WT) and CF mice were used at postnatal day 5 (P5) through adult. Pieces of small intestine were used to measure contractile activity of the circular muscle. Bacterial overgrowth was measured by quantitative polymerase chain reaction (PCR) of the bacterial 16S gene. Intestinal gene expression was determined by quantitative reverse transcription polymerase chain reaction (RT-PCR). Prostaglandin E2 (PGE2) and its metabolites were measured by enzyme immunoassay. RESULTS CF circular muscle response to cholinergic stimulation was similar to WT at P5, became somewhat impaired at P7, and was severely impaired by P14. In the CF intestine, bacterial overgrowth occurred by P4 and was maintained into adulthood. Eicosanoid metabolic gene expression in the CF intestine did not differ from WT shortly after birth. The phospholipase A2 genes, Pla2g4c and Pla2g5 exhibited increased expression in CF mice at P24. Prostaglandin degradative genes, Hpgd and Ptgr1, showed lower expression in CF as compared with WT at P16 and P24, respectively. PGE2 levels were significantly greater in CF mice at most ages from P7 through adulthood. CONCLUSIONS The results clearly demonstrate that lack of CFTR itself does not cause smooth muscle dysfunction, because the circular muscle from P5 CF mice had normal activity and dysfunction developed between P7 and P14.
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Affiliation(s)
- Robert C De Lisle
- University of Kansas School of Medicine, Anatomy and Cell Biology, Kansas City, KS 66160, USA.
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Mariani ME, Villarreal MA, Cheung F, Leiva EPM, Madoery RR, Fidelio GD. In silico and in vitro characterization of phospholipase A₂ isoforms from soybean (Glycine max). Biochimie 2012; 94:2608-19. [PMID: 23281487 DOI: 10.1016/j.biochi.2012.07.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
At the present, no secreted phospholipase A₂ (sPLA₂) from soybean (Glycine max) was investigated in detail. In this work we identified five sequences of putative secreted sPLA₂ from soybean after a BLAST search in G. max database. Sequence analysis showed a conserved PA2c domain bearing the Ca²⁺ binding loop and the active site motif. All the five mature proteins contain 12 cysteine residues, which are commonly conserved in plant sPLA₂s. We propose a phylogenetic tree based on sequence alignment of reported plant sPLA₂s including the novel enzymes from G. max. According to PLA₂ superfamily, two of G. max sPLA₂s are grouped as XIA and the rest of sequences as XIB, on the basis of differences found in their molecular weights and deviating sequences especially in the N- and C-terminal regions of the isoenzymes. Furthermore, we report the cloning, expression and purification of one of the putative isoenzyme denoted as GmsPLA₂-XIA-1. We demonstrate that this mature sPLA₂ of 114 residues had PLA₂ activity on Triton:phospholipid mixed micelles and determine the kinetic parameters for this system. We generate a model based on the known crystal structure of sPLA₂ from rice (isoform II), giving first insights into the three-dimensional structure of folded GmsPLA₂-XIA-1. Besides describing the spatial arrangement of highly conserved pair HIS-49/ASP-50 and the Ca⁺² loop domains, we propose the putative amino acids involved in the interfacial recognition surface. Additionally, molecular dynamics simulations indicate that calcium ion, besides its key function in the catalytic cycle, plays an important role in the overall stability of GmsPLA₂-XIA-1 structure.
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Affiliation(s)
- María Elisa Mariani
- Centro de Investigaciones en Química Biológica de Córdoba, (CIQUIBIC, UNCeCONICET), Departamento de Química Biológica, Fac. de Cs. Químicas, Universidad Nacional de Córdoba, Haya de Torre y Medina Allende, Ciudad Universitaria, X5000HUA Córdoba, Argentina
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240
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Peng Y, Chen J, He S, Yang J, Wu H. Release of ATP from marginal cells in the cochlea of neonatal rats can be induced by changes in extracellular and intracellular ion concentrations. PLoS One 2012; 7:e47124. [PMID: 23071731 PMCID: PMC3468545 DOI: 10.1371/journal.pone.0047124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 09/10/2012] [Indexed: 11/18/2022] Open
Abstract
Background Adenosine triphosphate (ATP) plays an important role in the cochlea. However, the source of ATP and the mechanism by which it is released remain unclear. This study investigates the presence and release mechanism of ATP in vitro cultured marginal cells isolated from the stria vascularis of the cochlea in neonatal rats. Methods Sprague-Dawley rats aged 1–3 days old were used for isolation, in vitro culture, and purification of marginal cells. Cultured marginal cells were verified by flow cytometry. Vesicles containing ATP in these cells were identified by fluorescence staining. The bioluminescence assay was used for determination of ATP concentration in the extracellular fluid released by marginal cells. Assays for ATP concentration were performed when the ATP metabolism of cells was influenced, and ionic concentrations in intracellular and extracellular fluid were found to change. Results Evaluation of cultured marginal cells with flow cytometry revealed the percentage of fluorescently-labeled cells as 92.9% and 81.9%, for cytokeratin and vimentin, respectively. Quinacrine staining under fluorescence microscopy revealed numerous green, star-like spots in the cytoplasm of these cells. The release of ATP from marginal cells was influenced by changes in the concentration of intracellular and extracellular ions, namely extracellular K+ and intra- and extracellular Ca2+. Furthermore, changes in the concentration of intracellular Ca2+ induced by the inhibition of the phospholipase signaling pathway also influence the release of ATP from marginal cells. Conclusion We confirmed the presence and release of ATP from marginal cells of the stria vascularis. This is the first study to demonstrate that the release of ATP from such cells is associated with the state of the calcium pump, K+ channel, and activity of enzymes related to the phosphoinositide signaling pathway, such as adenylate cyclase, phospholipase C, and phospholipase A2.
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Affiliation(s)
- Yating Peng
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Department of Otolaryngology, Integrated Chinese and Western Medicine Hospital of Zhejiang Province, Hangzhou Red Cross Hospital, Hangzhou, China
| | - Jie Chen
- Department of Otolaryngology, Shanghai Children's Medical Center, Shanghai, China
| | - Shan He
- Department of Otolaryngology, People's Hospital of Shanghai Pudong District, Shanghai, China
| | - Jun Yang
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China
- * E-mail:
| | - Hao Wu
- Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China
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Liu Y, Cheng D, Lin IH, Abbott NL, Jiang H. Microfluidic sensing devices employing in situ-formed liquid crystal thin film for detection of biochemical interactions. Lab Chip 2012; 12:3746-53. [PMID: 22842797 PMCID: PMC3448960 DOI: 10.1039/c2lc40462a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Although biochemical sensing using liquid crystals (LC) has been demonstrated, relatively little attention has been paid towards the fabrication of in situ-formed LC sensing devices. Herein, we demonstrate a highly reproducible method to create uniform LC thin film on treated substrates, as needed, for LC sensing. We use shear forces generated by the laminar flow of aqueous liquid within a microfluidic channel to create LC thin films stabilized within microfabricated structures. The orientational response of the LC thin films to targeted analytes in aqueous phases was transduced and amplified by the optical birefringence of the LC thin films. The biochemical sensing capability of our sensing devices was demonstrated through experiments employing two chemical systems: dodecyl trimethylammonium bromide (DTAB) dissolved in an aqueous solution, and the hydrolysis of phospholipids by the enzyme phospholipase A(2) (PLA(2)).
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Affiliation(s)
- Ye Liu
- Department of Electrical and Computer Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706, USA
| | - Daming Cheng
- Material Science Program, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706, USA
| | - I-Hsin Lin
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706, USA
| | - Nicholas L. Abbott
- Material Science Program, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706, USA
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706, USA
| | - Hongrui Jiang
- Department of Electrical and Computer Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706, USA
- Material Science Program, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI 53706, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, 1550 Engineering Drive, Madison, WI 53706, USA
- Fax: 1-608-262-1267; Tel: 1-608-265-9418;
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ElBaradie K, Wang Y, Boyan BD, Schwartz Z. Rapid membrane responses to dihydrotestosterone are sex dependent in growth plate chondrocytes. J Steroid Biochem Mol Biol 2012; 132:15-23. [PMID: 22207084 DOI: 10.1016/j.jsbmb.2011.12.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Revised: 12/05/2011] [Accepted: 12/07/2011] [Indexed: 10/14/2022]
Abstract
Sex steroids are important regulators for longitudinal growth, bone mass accrual, and sexual dimorphism of the skeleton. 17β-Estradiol regulates proliferation and differentiation of female chondrocytes via a membrane-associated signaling pathway in addition to its estrogen receptor (ER) mediated effects. In contrast, testosterone does not elicit a similar membrane response, either in male or female cells. Whereas female rat growth plate chondrocytes convert testosterone to 17β-estradiol, male chondrocytes produce 5α-dihydrotestosterone (DHT). Previously DHT was found to mediate sex-specific effects of testosterone in male cells, but it is not known if a membrane-signaling pathway is involved. In this study, we hypothesized that DHT can induce sex-specific rapid membrane effects similar to other steroid hormones. Confluent cultures of chondrocytes isolated from resting zones of growth plates of both male and female rats were treated with 10(-10)-10(-7)M testosterone or DHT for 3, 9, 90 and 270min and protein kinase C (PKC) and phospholipase A2 (PLA2) activities were measured. To examine potential signaling pathways involved in PKC activation, male chondrocytes were treated with 10(-7)M DHT for 9min in the presence or absence of the phospholipase C (PLC) inhibitor U73122, the secretory PLA2 inhibitor quinacrine or the cytosolic PLA2 inhibitor AACOCF3; the Gαi inhibitor pertussis toxin (PTX) or Gαs activator cholera toxin (CTX), and the general G-protein inhibitor GDPβS; thapsigargin, an inhibitor of a Ca-ATPase pump in the endoplasmic reticulum; verapamil and nifedipine, inhibitors of specific L type Ca2+ channels on the cell membrane; and cyproterone acetate (CPA), which is an inhibitor of the classical androgen receptor (AR); as well as the transcription inhibitor actinomycin D, or the translation inhibitor cycloheximide. DHT induced a dose-dependent increase in PKC and PLA2 activity in male cells with the highest increase at 10(-7)M DHT (p<0.05), whereas testosterone had no effect. PKC activity was augmented at 9 and 90 min, and then decreased to baseline at 270min. Neither testosterone nor DHT affected PKC in female cells. U73122, quinacrine, and AACOCF3 inhibited DHT-induced activation of PKC. DHT treatment for 9 min had no effect in [(3)H]-thymidine incorporation in quiescent confluent cultures but caused a dose dependent increase in alkaline phosphatase specific activity. Inhibition of PLC reduced the response of to DHT in a dose dependent manner, indicating that PLC is involved. In conclusion, our study indicates that DHT, but not testosterone, has sex-specific rapid membrane effects in male growth plate chondrocytes involving PLC and PLA2-mediated PKC signaling pathways. Together with previous observations showing that male cells convert testosterone to DHT, these results suggest that DHT might act in the membrane through an autocrine/paracrine mechanism.
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Affiliation(s)
- Khairat ElBaradie
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, United States
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Altinbas B, Topuz BB, Yilmaz MS, Aydin C, Savci V, Jochem J, Aydin S, Yalcin M. The mediation of the central histaminergic system in the pressor effect of intracerebroventricularly injected melittin, a phospholipase A2 activator, in normotensive rats. Prostaglandins Leukot Essent Fatty Acids 2012; 87:153-8. [PMID: 22995146 DOI: 10.1016/j.plefa.2012.08.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 07/24/2012] [Accepted: 08/22/2012] [Indexed: 11/23/2022]
Abstract
Melittin is a polypeptide component of bee venom that leads to an increase in arachidonic acid release and subsequently in prostaglandin synthesis by activating phospholipase A(2). Recently we demonstrated that centrally or peripherally administrated melittin caused pressor effect and central thromboxane A(2) (TXA(2)) and cholinergic system mediated these effects of melittin. Also centrally injected histamine leads to pressor and bradycardic response by activating central histamine receptors in normotensive rats and central cholinergic system involved the effects of histamine. The present study demonstrates an involvement of the central histaminergic system in melittin-induced cardiovascular effect in normotensive rats. Experiments were carried out in male Sprague Dawley rats. Intracerebroventricularly (i.c.v.) injected melittin (0.5, 1 and 2 nmol) caused dose- and time-dependent increases in mean arterial pressure (MAP) and decrease in heart rate (HR) as we reported previously. Moreover, H(2) receptor antagonist ranitidine (50 nmol; i.c.v.) almost completely and H(3)/H(4) receptor antagonist thioperamide (50 nmol; i.c.v.) partly blocked melittin-evoked cardiovascular effects, whereas H(1) receptor blocker chlorpheniramine (50 nmol; i.c.v.) had no effect. Also centrally injected melittin was accompanied by 28% increase in extracellular histamine concentration in the posterior hypothalamus, as shown in microdialysis studies. In conclusion, results show that centrally administered melittin causes pressor and bradycardic response in conscious rats. Moreover, according to our findings, there is an involvement of the central histaminergic system in melittin-induced cardiovascular effects.
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Affiliation(s)
- Burcin Altinbas
- Department of Physiology, Faculty of Veterinary Medicine, Uludag University, 16059 Bursa, Turkey
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Doroudi M, Schwartz Z, Boyan BD. Phospholipase A2 activating protein is required for 1α,25-dihydroxyvitamin D3 dependent rapid activation of protein kinase C via Pdia3. J Steroid Biochem Mol Biol 2012; 132:48-56. [PMID: 22484374 DOI: 10.1016/j.jsbmb.2012.03.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 02/12/2012] [Accepted: 03/06/2012] [Indexed: 11/25/2022]
Abstract
1α,25-Dihydroxyvitamin D(3) (1,25D3) regulates musculoskeletal cells via two different mechanisms: vitamin D receptor (VDR)-dependent gene transcription and rapid membrane-signaling via VDR as well as protein disulfide isomerase, family A, member 3 (Pdia3). In chondrocytes from the costochondral cartilage growth zone (GC), ligand binding to Pdia3 causes a rapid increase in phospholipase A(2) (PLA(2)) activity leading to release of arachidonic acid and formation of lysophospholipid (LPL). LPL activates phospholipase C (PLC), and resulting inositol trisphosphate (IP(3)) and diacylglycerol contribute to PKCα activation and downstream activation of ERK1/2. PLA(2) activating protein (PLAA) is increased in the growth zone of rat growth plates suggesting that it mediates the 1,25D3-dependent pathway. This study examined the role of PLAA in mediating 1,25D3-dependent PKC activation using GC cells and MC3T3-E1 wild-type and PLAA-silenced osteoblasts as models. PLAA, Pdia3, and caveolin-1 (Cav-1) were detected in plasma membranes and caveolae of GC and MC3T3-E1 cells. Pdia3-immunoprecipitated samples were positive for PLAA only after 1,25D3 treatment. Cav-1 was detected when immunoprecipitated with anti-Pdia3 and anti-PLAA in both vehicle and 1,25D3 treated cells. These observations were confirmed by immunohistochemistry. 1,25D3 failed to activate PLA(2) and PKC or cause PGE(2) release in PLAA-silenced cells. PLAA-antibody successfully blocked the PLAA protein and consequently suppressed PKC activity in GC and MC3T3-E1 cells. Crosslinking studies confirmed the localization of PLAA on the extracellular face on the plasma membrane in untreated MC3T3-E1 cells. Taken together, our results suggest that PLAA is an important mediator of 1α,25(OH)(2)D(3) rapid membrane mediated signaling. 1α,25(OH)(2)D(3) likely causes conformational changes bringing Pdia3 into proximity with PLAA, and aiding in transducing the signal from caveolae to the plasma membrane.
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Affiliation(s)
- Maryam Doroudi
- School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA
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Sui HY, Luan HY, Liu YJ. Involvement of protein kinase A activation and phospholipase A(2) inhibition in the adenosine-activated basolateral 50 pS K(+) channels in the thick ascending limb of the rat kidney. Sheng Li Xue Bao 2012; 64:449-454. [PMID: 22907306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The present study was designed to investigate the role of protein kinase A (PKA) and phospholipase A(2) (PLA(2)) in the stimulating effect of adenosine on the basolateral 50 pS K(+) channels in the thick ascending limb (TAL) of the rat kidney. Under the anatomic microscope, the TAL was dissected. The current of 50 pS K(+) channels were recorded by patch clamp technology. The protein expression of phosphorylated PKA and phosphorylated PLA(2) were examined by Western blot. The results showed that cyclohexyladenosine (CHA), an analog of adenosine, increased the 50 pS K(+) channel activity (P < 0.05). In the presence of H8, an antagonist of PKA, CHA did not affect the 50 pS K(+) channel activity. In the presence of AACOCF3 (an antagonist of PLA(2)), CHA did not further increase the 50 pS K(+) channel activity. CHA increased phosphorylation level of PKA, whereas inhibited phosphorylation of PLA(2) in the TAL of the rat kidney (P < 0.01). Furthermore, after blocking the PLA(2) with AACOCF3, CHA still increased the expression of phosphorylated PKA. On the contrary, CHA did not obviously change the expression of phosphorylated PLA(2) after H8 pretreatment. The results suggest that the stimulation of basolateral 50 pS K(+) channels by CHA is mediated by the activation of PKA followed by the inhibition of PLA(2) in the TAL of the rat kidney.
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Affiliation(s)
- Hong-Yu Sui
- Department of Physiology, Jiamusi University, Jiamusi 154002, China.
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Lambert JD, Yennawar N, Gu Y, Elias RJ. Inhibition of secreted phospholipase A2 by proanthocyanidins: a comparative enzymological and in silico modeling study. J Agric Food Chem 2012; 60:7417-7420. [PMID: 22779786 PMCID: PMC3740037 DOI: 10.1021/jf302308k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Secreted phospholipase A2 (PLA2) plays a critical role in mobilizing arachidonic acid in phospholipids. We have previously reported that PLA2 is inhibited by B-type proanthocyanidins (PaCs). To further understand the inhibitory activity of these compounds, we compared the inhibitory potency of B-type PaCs to that of A-type PaCs and modeled them with PLA2 using in silico techniques. The B-type trimer and tetramer inhibited PLA2 (IC50 = 16 and 10 μM). The A-type compounds were less potent (18-35% inhibition at 50 μM). The active site of PLA2 lies in a hydrophobic tunnel. Modeling studies revealed that the B-type PaCs occupy this tunnel and are stabilized by a number of van der Waals interactions. The result is reduced substrate access to the active site. The A-type compounds can occupy this tunnel only by shifting the N-terminal loop outward. Our data provide a structural basis to screen additional PaCs for anti-PLA2 activity.
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Affiliation(s)
- Joshua D. Lambert
- Center of Excellence for Plant and Mushroom Foods for Health, Department of Food Science, The Pennsylvania State University, 202 Food Science Building, University Park, PA, USA 16802
| | - Neela Yennawar
- X-ray Crystallography Facility, The Huck Institutes of the Life Sciences, The Pennsylvania State University, 8 Althouse Laboratory, University Park, PA, USA 16802
| | - Yeyi Gu
- Center of Excellence for Plant and Mushroom Foods for Health, Department of Food Science, The Pennsylvania State University, 202 Food Science Building, University Park, PA, USA 16802
| | - Ryan J. Elias
- Center of Excellence for Plant and Mushroom Foods for Health, Department of Food Science, The Pennsylvania State University, 202 Food Science Building, University Park, PA, USA 16802
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247
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Nevalainen TJ, Cardoso JCR. Conservation of group XII phospholipase A2 from bacteria to human. Comp Biochem Physiol Part D Genomics Proteomics 2012; 7:340-50. [PMID: 22909802 DOI: 10.1016/j.cbd.2012.07.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 07/18/2012] [Accepted: 07/18/2012] [Indexed: 12/26/2022]
Abstract
Vertebrate group XII phospholipases A(2) (GXII PLA(2), conserved domain pfam06951) are proteins with unique structural and functional features within the secreted PLA(2) family. In humans, two genes (GXIIA PLA(2) and GXIIB PLA(2)) have been characterised. GXIIA PLA(2) is enzymatically active whereas GXIIB PLA(2) is devoid of catalytic activity. Recently, putative homologues of the vertebrate GXII PLA(2)s were described in non-vertebrates. In the current study a total of 170 GXII PLA(2) sequences were identified in vertebrates, invertebrates, non-metazoan eukaryotes, fungi and bacteria. GXIIB PLA(2) was found only in vertebrates and the searches failed to identify putative GXII PLA(2) homologues in Archaea. Comparisons of the predicted functional domains of GXII PLA(2)s revealed considerable structural identity within the Ca(2+)-binding and the catalytic sites among the various organisms suggesting that functional conservation may have been retained across evolution. The preservation of GXII PLA(2) family members from bacteria to human indicates that they have emerged early in evolution and evolved via gene/genome duplication events prior to Eubacteria. Gene duplicates were identified in some invertebrate taxa suggesting that species-specific duplications occurred. The analysis of the GXII PLA(2) homologue genome environment revealed that gene synteny and gene order are preserved in vertebrates. Conservation of GXII PLA(2)s indicates that important functional roles involved in species survival and were maintained across evolution and may be dependent on or independent of the enzyme's phospholipolytic activity.
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248
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Chavanayarn C, Thanongsaksrikul J, Thueng-in K, Bangphoomi K, Sookrung N, Chaicumpa W. Humanized-single domain antibodies (VH/VHH) that bound specifically to Naja kaouthia phospholipase A2 and neutralized the enzymatic activity. Toxins (Basel) 2012; 4:554-67. [PMID: 22852068 PMCID: PMC3407892 DOI: 10.3390/toxins4070554] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 06/26/2012] [Accepted: 07/06/2012] [Indexed: 12/19/2022] Open
Abstract
Naja kaouthia (monocled cobra) venom contains many isoforms of secreted phospholipase A2 (sPLA2). The PLA2 exerts several pharmacologic and toxic effects in the snake bitten subject, dependent or independent on the enzymatic activity. N. kaouthia venom appeared in two protein profiles, P3 and P5, after fractionating the venom by ion exchange column chromatography. In this study, phage clones displaying humanized-camel single domain antibodies (VH/VHH) that bound specifically to the P3 and P5 were selected from a humanized-camel VH/VHH phage display library. Two phagemid transfected E. coli clones (P3-1 and P3-3) produced humanized-VHH, while another clone (P3-7) produced humanized-VH. At the optimal venom:antibody ratio, the VH/VHH purified from the E. coli homogenates neutralized PLA2 enzyme activity comparable to the horse immune serum against the N. kaouthia holo-venom. Homology modeling and molecular docking revealed that the VH/VHH covered the areas around the PLA2 catalytic groove and inserted their Complementarity Determining Regions (CDRs) into the enzymatic cleft. It is envisaged that the VH/VHH would ameliorate/abrogate the principal toxicity of the venom PLA2 (membrane phospholipid catabolism leading to cellular and subcellular membrane damage which consequently causes hemolysis, hemorrhage, and dermo-/myo-necrosis), if they were used for passive immunotherapy of the cobra bitten victim. The speculation needs further investigations.
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Affiliation(s)
- Charnwit Chavanayarn
- Graduate Program in Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand;
| | - Jeeraphong Thanongsaksrikul
- Laboratory for Research and Technology Development, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (J.T.); (K.T.)
| | - Kanyarat Thueng-in
- Laboratory for Research and Technology Development, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (J.T.); (K.T.)
| | - Kunan Bangphoomi
- Department of Biochemistry, Kasetsart University, Bangkok 10900, Thailand;
| | - Nitat Sookrung
- Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand;
| | - Wanpen Chaicumpa
- Laboratory for Research and Technology Development, Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand; (J.T.); (K.T.)
- Author to whom correspondence should be addressed; ; Tel.: +662-4196-497; Fax: +662-4196-491
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249
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Mele PG, Duarte A, Paz C, Capponi A, Podestá EJ. Role of intramitochondrial arachidonic acid and acyl-CoA synthetase 4 in angiotensin II-regulated aldosterone synthesis in NCI-H295R adrenocortical cell line. Endocrinology 2012; 153:3284-94. [PMID: 22549224 DOI: 10.1210/en.2011-2108] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Although the role of arachidonic acid (AA) in angiotensin II (ANG II)- and potassium-stimulated steroid production in zona glomerulosa cells is well documented, the mechanism responsible for AA release is not fully described. In this study we evaluated the mechanism involved in the release of intramitochondrial AA and its role in the regulation of aldosterone synthesis by ANG II in glomerulosa cells. We show that ANG II and potassium induce the expression of acyl-coenzyme A (CoA) thioesterase 2 and acyl-CoA synthetase 4, two enzymes involved in intramitochondrial AA generation/export system well characterized in other steroidogenic systems. We demonstrate that mitochondrial ATP is required for AA generation/export system, steroid production, and steroidogenic acute regulatory protein induction. We also demonstrate the role of protein tyrosine phosphatases regulating acyl-CoA synthetase 4 and steroidogenic acute regulatory protein induction, and hence ANG II-stimulated aldosterone synthesis.
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Affiliation(s)
- Pablo G Mele
- Department of Biochemistry, School of Medicine, University of Buenos Aires, Institute of Biomedical Investigations, UBA-Consejo Nacional de Investigaciones Científicas y Técnicas, Paraguay 2155, 5 Floor, C1121ABG Buenos Aires, Argentina
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250
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Abstract
PURPOSE OF REVIEW The phospholipase A2 (PLA2) family of proteins includes lipolytic enzymes that liberate the sn-2 fatty acyl chains from phospholipids to yield nonesterified fatty acids and lysophospholipids. The purpose of this review is to discuss recent findings showing distinct roles of several of these PLA2 enzymes in inflammatory metabolic diseases such as diabetes and atherosclerosis. RECENT FINDINGS The group 1B PLA2 digestion of phospholipids in the intestinal lumen facilitates postprandial lysophospholipid absorption, which suppresses hepatic fatty acid oxidation leading to increased VLDL synthesis, decreased glucose tolerance, and promotion of tissue lipid deposition to accentuate diet-induced hyperlipidemia, diabetes, and obesity. Other secretory PLA2s promote inflammatory metabolic diseases by generating bioactive lipid metabolites to induce inflammatory cytokine production, whereas the major intracellular PLA2s, cPLA2α, and iPLA2, generate arachidonic acid and lysophosphatic acid in response to extracellular stimuli to activate leukocyte chemotactic response. SUMMARY Each member of the PLA2 family of enzymes serves a distinct role in generating active lipid metabolites that promote inflammatory metabolic diseases including atherosclerosis, hyperlipidemia, obesity, and diabetes. The development of specific drugs that target one or more of these PLA2 enzymes may be novel strategies for treatment of these chronic inflammatory metabolic disorders.
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Affiliation(s)
- David Y Hui
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
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