No abstract available.
Phosphatidylcholines* ; Phospholipases A2* ; Phospholipases*

Spider venoms and toxins are valuable sources of lead compounds for drug development due to their essential role in cellular and physiological processes targeting various receptors. Here, we present the protein profile of the venom of Phlogiellus bundokalbo, an endemic Philippine tarantula, to screen and characterize its cytotoxicity against MCF-7 cells, secretory phospholipase a2 (sPLA2), and neurotoxicity to evaluate its potential anticancer properties. Spider venom was extracted via electrical stimulation. Venom components were fractionated by reversed-phase high-performance liquid chromatography and characterized through liquid chromatography-mass spectrometry (LC-MS) and SDS-PAGE analysis before assay. The resulting five venom fractions were amphiphilic peptides showing cytotoxicity against MCF-7 cells in a concentrationdependent manner (IC50 ranging from 52.25μg/ml to 110.20μg/ml) after 24-hour incubation. Cells appeared detached, rounded, and shrunk with cytoplasmic condensation upon overnight incubation with venom fractions. The sPLA2 was observed in all the venom fractions tested for cytotoxicity. Venom fractions revealed a predominant mass of ~3-5 kDa with LC-MS analysis. Results showed distinct similar mass as μ- theraphotoxin-Phlo1a, an Australian tarantula, Phlogiellus sp. toxin with inhibitor cystine knot motif. The venom fractions exhibit excitatory neurotoxins that might activate presynaptic voltage-gated ion channels, such as an agonist or gating modifier toxins that slow down the channel inactivation similar to spider toxins. In conclusion, the spider venom of P. bundokalbo exhibits cytotoxic, phospholipase A2, and neuroactive properties suggesting that its venom components, upon further purification and structure-function analysis, can be potential tools in the development of targeted breast chemotherapeutics.
Spider Venoms ; Phospholipases

No abstract available.
Macrophages* ; Phospholipases A2* ; Phospholipases* ; Tumor Necrosis Factor-alpha*

No abstract available.
Animals ; Glucose* ; Mesangial Cells* ; Phospholipases A2* ; Phospholipases* ; Rats*

No abstract available.
Animals ; Inositol* ; Kidney* ; Liver* ; Phospholipases* ; Rats* ; Type C Phospholipases*

This study investigated the effects of the methanol extracts of Morinda citrifolia containing numerous anthraquinone and iridoid on phospholipase A2 (PLA2) isozyme. PLA2 activity was measured using various PLA2 substrates, including 10-pyrene phosphatidylcholine, 1-palmitoyl-2-[14C]arachidonyl phosphatidylcholine ([14C]AA-PC), and [3H]arachidonic acid (AA). The methanol extracts suppressed melittin-induced [3H]AA release in a concentration-dependent manner in RAW 264.7 cells, and inhibited cPLA2/sPLA2-induced hydrolysis of [14C]AA-PC in a concentration- and time-dependent manner. A Dixon plot showed that the inhibition by methanol extracts on cPLA2 and sPLA2 appeared to be competitive with inhibition constants (Ki ) of 3.7microgram/ml and 12.6microgram/ml, respectively. These data suggest that methanol extracts of Morinda citrifolia inhibits both Ca2+-dependent PLA2 such as, cPLA2 and sPLA2. Therefore, Morinda citrifolia may possess anti-inflammatory activity secondary to Ca2+-dependent PLA2 inhibition.
Arachidonic Acid ; Cytosol ; Hydrolysis ; Methanol ; Morinda ; Phosphatidylcholines ; Phospholipases ; Phospholipases A2

No abstract available.
Animals ; Brain* ; Inositol* ; Phospholipases* ; Rats*

BACKGROUND: According to the notion of the immunoregulatory functions of moxifloxacin (MFX), the effect of MFX on the neutrophilic respiratory burst in conjunction with the expression of cytosolic phospholipase A2 (cPLA2) was investigated. METHODS: The effects and possible mechanisms of MFX on neutrophilic respiratory burst in oleic acid (OA)-induced acutely injured rats lung and OA-stimulated, isolated murine neutrophils were probed, associated with the expression of cytosolic phospholipase A2 in vivo and in vitro. RESULTS: In the OA-induced acutely-injured lungs, neutrophils were accumulated, which was attenuated by MFX. The parameters denoting a neutrophilic respiratory burst, such as nitro blue tetrazolium reaction, cytochrome-c reduction, neutrophil aggregation, H2O2 production in neutrophils revealed increased neutrophilic respiratory burst by OA, and MFX decreased all of these parameters. In addition, the enhanced expression of cPLA2 in the lung and isolated murine neutrophils by OA were decreased by MFX. CONCLUSION: MFX suppresses the OA-induced neutrophilic respiratory burst by the suppression of cPLA2 in neutrophils.
Animals ; Aza Compounds ; Cytosol ; Lung ; Neutrophils ; Oleic Acid ; Phospholipases ; Phospholipases A2 ; Phospholipases A2, Cytosolic ; Quinolines ; Rats ; Respiratory Burst

STUDY DESIGN: Evaluation of phospholipase A2 production according to cell type of human intervertebral disc. SUMMARY OF LITERATURE REVIEW: It was reported that the phospholipase A2 activity in human lumbar disc herniation was more active than that in other tissues. OBJECTIVES: The purpose of this study was to evaluate the differences between the cells of anulus fibrosus and nucleus pulposus when lactate was added to the culture medium. MATERIALS AND METHODS: Cells from the anulus fibrosus and nucleus pulposus of a human intervertebral disc were prepared enzymatically. After the monolayer was set up, the cells were divided to three groups and lactate doses of a 0mM, 2mM or 5mM were added respectively. At two week after lactate addition the production of phospholipase A2 was measured by Northern blotting. RESULTS: Cells of nucleus pulposus produced a small amount of phospholipase A2. Those of anulus fibrosus showed a high activity of phospholipase A2 production. The concentration of lactate did not influenced on the production of phospholipase A2. CONCLUSION: The anulus fibrosus has an important role in the production of phospholipase A2 and is thought to be related with generation of discogenic pain.
Blotting, Northern ; Cell Culture Techniques ; Humans* ; Intervertebral Disc* ; Lactic Acid ; Phospholipases A2* ; Phospholipases*

OBJECTIVES: A limited retrospective study of patients with rheumatoid arthritis (RA) found that serum phospholipase A2 (PLA2) activity correlates with disease activity. To assess the strength of this relationship we investigated prospectively 25 patients with RA using a double blind approach. METHODS: Twenty five patients who fulfilled the 1987 American College of Rheumatology criteria for RA had clinical and laboratory assessments. PLA2 activity was measured before and after treatment of 3 months in patients with RA. Fourteen healthy individuals were also enrolled as controls. PLA2 activity was assayed using E.coli membrane phospholipid substrate labelled with[14C]-oleic acid. RESULTS: 1) Serum PLA2 activity was significantly higher in patients with RA than that of normal healthy controls (p<0.001). 2) In Patients with RA, synovial fluid PLA2 activity was higher than serum PLA2 activity, and a positive correlation between PLA2 in synovial fluids and matched sera was found in these patients (p<0.05). 3) After treatment, PLA2 activity was significantly decreased with improvement of clinical(morning stiffness and Ritchie index) and laboratory(ESR, CRP and rheumatoid factor)assessments (p<0.001). 4) Among the clinical and laboratory markers of disease activity, ESR showed the best correlation with serum PLA2 activity (r=0.493, p<0.05). 5) In the patients who did not respond clinically to treatment (n=5), there was no significant decrease in PLA2 activity. CONCLUSION: PLA2 activity significantly correlates with RA activity and may serve as an index of disease activity in RA.
Arthritis, Rheumatoid* ; Biomarkers ; Humans ; Membranes ; Phospholipases A2* ; Phospholipases* ; Prospective Studies ; Rheumatology ; Synovial Fluid