Biomedical subjects

J J Moreno

Publications and source records attributed to J J Moreno.

At least 19 recordsLinked to original sources

PubMed2001

Role of Ca2+-independent phospholipase A2 on arachidonic acid release induced by reactive oxygen species.

Previous studies have shown that reactive oxygen species (ROS) enhance arachidonic acid (AA) release and the subsequent AA metabolism in macrophages. The purpose of this study was determined the implication of phospholipases A2 (PLA2s) in these events. Our results show that oxidative stress induced by exogenous adding of hydrogen peroxide or superoxide anion in macrophage RAW 264.7 and mouse peritoneal macrophage cultures caused a marked enhancement of calcium-independent PLA2 (iPLA2) activity,whereas the increment of secreted PLA2 (sPLA2) and calcium-dependent cytosolic PLA2 (cPLA2) activities were slight. This increase of iPLA2 activity by ROS was rapid and dose-dependent. ROS also induced a significant [3H] arachidonic acid (AA) release. The iPLA2 selective inhibitor, bromoenol lactone, almost completely suppressed the mobilization of [3H]AA induced by ROS whereas antisense oligonucleotide against cPLA2 did not have any appreciable effect. Thus, our data show that iPLA2 activity is involved in the mechanism by which ROS increases the availability of free AA in macrophages RAW 264.7. Moreover, the protein kinase C (PKC) inhibitor, calphostin C, and calcium chelators had no effect on the [3H]AA release induced by ROS, suggesting this is a regulatory role of iPLA2.

Acetone↗

PubMed2001

The effect of high molecular phospholipase A2 inhibitors on 3T6 fibroblast proliferation.

Recently, we suggested that arachidonic acid and/or its cyclooxygenase pathway metabolites may be involved in regulating 3T6 fibroblast proliferation. In the present study we evaluate the role of high-molecular phospholipase A2 (PLA2) enzymes in the 3T6 fibroblast growth. Our results demonstrate that the cytosolic PLA2 inhibitor, arachidonyl trifluoromethylketone and the cytosolic calcium-independent PLA2 (iPLA2) inhibitor, bromoenol lactone, decrease arachidonic acid release and prostaglandin E2 production in 3T6 fibroblast cultures stimulated by fetal calf serum. These effects were correlated with the impairment of 3T6 fibroblast proliferation and DNA synthesis at the S/G2 boundary, which prolongs the S phase. These data suggest a role of iPLA2 in the control of 3T6 fibroblast growth.

Animals↗

PubMed2001

Role of phospholipases A(2) in growth-dependent changes in prostaglandin release from 3T6 fibroblasts.

Previously, we reported a growth-dependent change in prostaglandin production as a consequence of a marked growth-dependent alteration in arachidonic acid (AA) mobilization from phospholipids. Our present results show that fetal calf serum (FCS) and 4 beta-phorbol-12-myristate acetate (PMA) caused an enhancement of phospholipase A(2) (PLA(2)) activity in the membrane fraction of non-confluent cells allowing PLA(2) access to its substrate and the release of AA. Western blot analysis has shown that FCS and PMA increased secreted PLA(2) (sPLA(2)) expression in non-confluent 3T6 fibroblast cultures. Moreover, FCS and PMA induced dithiothreitol-sensitive and bromoenol lactone-sensitive PLA(2) activities in cytosol and membrane fraction. However, these stimuli did not modify significantly the PLA(2) activity in both fractions when 3T6 fibroblasts reached a high cell density. This could be associated with the impairment of AA mobilization in these cell culture conditions. On the other hand, we observed that FCS and PMA induced the same prostaglandin H synthase-2 induction in non-confluent and confluent culture conditions. Moreover, the prostaglandin E(2) levels reached in cell culture supernatants were independent of the degree of confluence when AA was added exogenously. These results suggest that the changes of intracellular distribution of PLA(2) activity of sPLA(2) and iPLA(2) stimulated by exogenous stimuli may be controlled by cell density conditions which constitute an important mechanism in the regulation of prostaglandin release.

Animals↗

PubMed2001

Olive oil decreases both oxidative stress and the production of arachidonic acid metabolites by the prostaglandin G/H synthase pathway in rat macrophages.

Fish oil has a preventive role in cardiovascular and inflammatory diseases, but little is known about the effect of olive oil, which is widely consumed in Mediterranean regions. We examined the influence of dietary olive oil, corn oil and fish oil-rich diets on the production of superoxide anion (O2-) and nitric oxide (.NO) by resident macrophages stimulated by phorbol 12-myristate 13-acetate (PMA) and their effect on arachidonic acid release, prostaglandin G/H synthase-2 (PGHS-2) expression and the subsequent prostaglandin E(2) production. Resident peritoneal macrophages stimulated by PMA from rats fed with olive oil or corn oil had the same level of O2- production, but these levels were increased by the fish oil diet. Olive oil and the fish oil diets increased .NO and decreased arachidonic acid mobilization and the production of prostaglandin E(2). PGHS-2 expression, however, was not affected by diet. We conclude that although olive oil and fish oil reduce arachidonic acid mobilization and subsequent metabolism through the PGHS-2 pathway in PMA-stimulated macrophages, only olive oil offers an additional beneficial effect by increasing .NO/O2- production.

Animals↗

PubMed2001

Antiflammin-2 prevents HL-60 adhesion to endothelial cells and prostanoid production induced by lipopolysaccharides.

We studied the effect of antiflammin-2 (AF-2) on adhesion molecule expression by HL-60 cells and endothelial (ECV304) cells stimulated by lipopolysaccharides (LPSs), and on leukocyte-endothelial cell interaction in an in vitro coculture system. The action of AF-2 on prostanoid production in these experimental conditions was also tested. LPS increased the adhesion molecule expression, such as lymphocyte function-associated antigen-1 and membrane attack complex-1 on HL-60 cells and E-selectin and intercellular adhesion molecule-1 on ECV304 cells. The LPS-stimulated adhesion molecule expression on HL-60/ECV304 coculture system was higher than on HL-60 or ECV304 cultures. LPS also induced HL-60 adhesion to ECV304 monolayer and thromboxane B(2) and prostaglandin E(2) (PGE(2)) production in HL-60 culture and PGE(2) in ECV304 culture. Prostanoid production by HL-60/ECV304 cocultures was higher than by simple cultures. AF-2 inhibited the enhancement of adhesion molecule expression induced by LPSs, especially E-selectin. Thus, AF-2 significantly reduced the HL-60 adhesion to endothelial cells stimulated by LPSs. AF-2 also inhibited prostanoid synthesis by ECV304 cells or HL-60/ECV304 coculture challenged by LPSs. In conclusion, AF-2 reduced HL-60 adhesion to endothelial cells, suggesting that it reduces inflammation by blocking leukocyte trafficking and the subsequent eicosanoid production.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2000

Effect of resveratrol, a natural polyphenolic compound, on reactive oxygen species and prostaglandin production.

Resveratrol is a natural molecule with antioxidant action. Moreover, resveratrol is also considered to be a molecule with anti-inflammatory action, an effect attributed to suppression of prostaglandin (PG) biosynthesis. The aim of the present study was to investigate the effects of resveratrol, a polyphenol present in most red wines, on reactive oxygen species formation as well as on arachidonic acid (AA) release, cyclooxygenase expression, and PG synthesis in murine resident peritoneal macrophages. Results show that resveratrol exerted a strong inhibitory effect on superoxide radical (O2-) and hydrogen peroxide (H2O2) produced by macrophages stimulated by lipopolysaccharides (LPS) or phorbol esters (PMA). Resveratrol also significantly decreased [3H]AA release induced by LPS and PMA or by exposure to O2- or H2O2. Resveratrol treatment caused a significant impairment of cyclooxygenase-2 (COX-2) induction stimulated by LPS and PMA or by O2- or H2O2 exposure. These effects of resveratrol on [3H]AA release and COX-2 overexpression were correlated with a marked reduction of PG synthesis. Our results indicate that the antioxidant action of resveratrol affects AA mobilization and COX-2 induction.

Animals↗

PubMed2000

Arachidonic acid release and prostaglandin E2 synthesis as irritant index of surfactants in 3T6 fibroblast cultures.

Surface-active agents are components of many drugs and cosmetics. [3H]arachidonic acid ([3H]AA) is rapidly incorporated into cell membrane phospholipids. As a result of membrane disintegration or enzymatic catalysis, it is released to the medium and [3H]AA metabolites can be measured by the scintillation technique. In order to validate the use of this test to predict the irritant and toxic effects of surfactants in vitro, various surfactants were examined using this methodology and the neutral red test. Benzalkonium chloride and sodium dodecylsulfate were more irritant and cytotoxic than amphoteric and non-ionic surfactants such as cocoamidopropylbetaine and Tween 80, respectively. The rank order of the toxicity/irritancy of these agents was similar to that given by other tests in vivo and in vitro. Moreover, our results confirm that the measurement of [3H]AA release in 3T6 fibroblast cultures is a sensitive assay of membrane damage.

Animals↗

PubMed2000

Regulation of prostaglandin E2 production by the superoxide radical and nitric oxide in mouse peritoneal macrophages.

The purpose of this study was to elucidate the role of NO and O2 on enzymatic components of cyclooxygenase (COX) pathway in peritoneal macrophages. Activation of murine peritoneal macrophages by lipopolysaccharides (LPS) resulted in time-dependent production of nitric oxide (NO) and prostaglandin E2 (PGE2). This stimulation was also accompanied by the production of other reactive oxygen species such as superoxide (O2-), and by increased expression of COX-2. Our results provide evidence that O2- may be involved in the pathways that result in arachidonate release and PGE2 formation by COX-2 in murine peritoneal macrophages stimulated by LPS. However, we were not able to demonstrate that NO participates in the regulation of PG production under our experimental conditions.

Animals↗

PubMed2000

Antiflammin peptides in the regulation of inflammatory response.

This review focuses on the role of antiflammins in the regulation of the inflammatory response, in particular acute inflammation. The results show that antiflammins were effective on several classical models of inflammation. Preliminary data suggest that antiflammin action may be due to their ability to suppress leukocyte trafficking to the lesion.

Acute Disease↗

PubMed2000

Resveratrol modulates arachidonic acid release, prostaglandin synthesis, and 3T6 fibroblast growth.

Previous results suggested that the cyclooxygenase-2 pathway and prostaglandins might modulate 3T6 fibroblast growth. This study shows the effect of resveratrol on the main elements of arachidonic acid (AA) cascade and 3T6 fibroblast growth. The polyphenol reduced the reactive oxygen species production stimulated by fetal calf serum or platelet-derived growth factor, as well as phospholipase A(2) activity translocation and the subsequent [(3)H]AA release and prostaglandin E(2) synthesis induced by these growth factors. A Western blot analysis demonstrated that cyclooxygenase-2 induction stimulated by fetal calf serum or platelet-derived growth factor was inhibited by resveratrol. The effects of resveratrol on AA cascade were correlated with an impairment of 3T6 fibroblast proliferation and DNA synthesis. These results suggest that reactive oxygen species and AA, and/or prostaglandins such as prostaglandin E(2) might be involved in the control of 3T6 fibroblast growth by resveratrol.

Animals↗

PubMed1999

Role of leukocyte influx in tissue prostaglandin H synthase-2 overexpression induced by phorbol ester and arachidonic acid in skin.

The accumulation of neutrophils and mononuclear cells is a characteristic feature of 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ear edema. This cell influx was accompanied by the enhancement of eicosanoid tissue levels and prostaglandin H synthase-2 (PGHS-2) overexpression. Sialidase treatment, which affects the structure of selectins and inhibits leukocyte influx, significantly reduced eicosanoid and PGHS-2 levels and edema. In contrast, skin PGHS-2 overexpression induced by arachidonic acid (AA) application was not affected by sialidase treatment. These results suggest that PGHS-2 overexpression induced by TPA could be induced by AA and/or AA metabolite release by leukocyte infiltrated during the inflammatory process.

Acute Disease↗

PubMed1999

Ketoprofen S(+) enantiomer inhibits prostaglandin production and cell growth in 3T6 fibroblast cultures.

The ketoprofen S(+) enantiomer inhibits with great stereoselectivity both prostaglandin H synthase isoenzymes. Thus, the biological effects of ketoprofen on inflammation are due almost entirely to the S(+) isomer. Here, we report that the S(+) enantiomer, at doses that inhibit prostaglandin synthesis, is effective in reducing DNA synthesis and 3T6 fibroblast growth. Our data suggest that prostaglandins are involved in the control of 3T6 fibroblast growth and that the effect of the ketoprofen S(+) enantiomer on 3T6 proliferation is correlated with its effects on prostaglandin H synthase and prostaglandin production.

Animals↗

PubMed1999

Role of prostaglandin H synthase isoforms in murine ear edema induced by phorbol ester application on skin.

Topical application of TPA to a murine ear induced an edema that was accompanied by eicosanoid biosynthesis and an early enhancement of prostaglandin H synthase 2 (PGHS-2) expression. PGHS-2 induction may be correlated with the time-course of TPA-induced edema formation. Treatment with drugs that inhibit AA mobilization such as dexamethasone or manoalide or inhibitors of leukotriene formation such as zileuton or baicalein, reduced TPA-induced edema development and PGHS-2 levels. On the other hand, arachidonic acid (AA) application on the murine ear induced rapid expression of PGHS-2. This effect was not reproduced by other fatty acids such as oleic, linoleic, eicosatetraynoic or eicosapentaenoic acids. PGHS-2 expression induced by AA application was independent of PGHS and lipoxygenase metabolite synthesis. However, topical application of PGE2 on skin induced PGHS-2 overexpression. This study suggests that AA release and/or subsequent metabolism by PGHS may be involved in the induction of PGHS-2 expression in murine TPA- and AA-induced ear oedema.

Animals↗

PubMed1999

Response of the aroma fraction in sherry wines subjected to accelerated biological aging.

The effect of an acceleration assay, carried out with a periodic aeration and an increased surface/volume ratio, on various aroma compounds of "fino" Sherry wines aging under a veil of a pure culture of Saccharomyces cerevisiae race capensis G1 flor film yeast was studied. The results were subjected to multifactor analysis of variance, and the compounds simultaneously depending on acceleration conditions and aging time at p < 0.01 were subjected to principal component analysis. The first component, accounting for 86.14% of the overall variance, was mainly defined by acetaldehyde and its derivatives 1,1-diethoxyethane and acetoin. These compounds reached higher concentrations in accelerated aging wines in a shorter time than they did in control wines, and no browning problems were detected. Taking into account that these compounds can be used as indicators for biological aging of "fino" Sherry wines, the acceleration condition assayed can be applied to shorten the time of this process.

Alcohols↗

PubMed1998

Induction by interleukin-1beta peptide of prostaglandin E2 formation via enhanced prostaglandin H synthase-2 expression in 3T6 fibroblasts.

Several synthetic interleukin-1 (IL-1) peptides were tested in vivo for pyrogenic activity and in vivo for their ability to stimulate prostaglandin production. Only the IL-1beta fragment (208-240) enhanced body temperature, although both IL-1beta (208-240) and IL-1alpha (223-250) stimulated prostaglandin E2 (PGE2) production in vitro. We report here that the IL-1beta fragment (208-240) did not have the capacity to induce arachidonic acid (AA) mobilization by 3T6 fibroblasts. However, this peptide was able to increase the expression of the inducible prostaglandin H synthase isoform (PGHS-2; EC 1.14.99.1.), which is related to its ability to stimulate prostaglandin E2 synthesis.

Animals↗

PubMed1997

Regulation of arachidonic acid release and prostaglandin formation by cell-cell adhesive interactions in wound repair.

Foetal calf serum (FCS) and platelet-derived growth factor (PDGF) induced arachidonate release in subconfluent murine 3T6 fibroblast cultures. However, the magnitude of this effect decreased significantly as the cell culture became confluent. Wound-induced injury of the fibroblast monolayer initiated a repair process that was potentiated by FCS or PDGF and which restored the integrity of cell monolayer. Under these experimental conditions, FCS and PDGF induced phospholipase A2 activity and subsequent arachidonic acid mobilization and production of eicosanoids in wounded fibroblast cultures. Finally, it is demonstrated that prostanoids, specifically prostaglandin E2, play an important role in cell proliferation induced by FCS and PDGF during wound repair.

Animals↗

PubMed1997

Antiflammins: endogenous nonapeptides with regulatory effect on inflammation.

1. Antiflammins are a new family of peptides that share a common sequence with uteroglobin and lipocortin-1, which retain the anti-inflammatory action of these proteins. 2. However, it is controversial whether or not the antiflammins have any effect on enzymes involved in arachidonic acid mobilization and/or arachidonic acid metabolism. 3. This review summarizes our current knowledge of the properties and activity of antiflammins.

Animals↗

PubMed1997

Role of prostaglandin H synthase-2-mediated conversion of arachidonic acid in controlling 3T6 fibroblast growth.

The specific role(s) of arachidonic acid (AA) and its metabolites in the signaling pathways that regulated fibroblast growth was studied. A Western blot analysis demonstrated that prostaglandin H synthase-2 (PGHS-2) was expressed by 3T6 fibroblast cultures in RPMI 1640 supplemented with fetal calf serum (10%). Dexamethasone, which inhibits AA release and PGHS-2 expression, significantly reduced cell proliferation. Ketoprofen, a dual cyclooxygenase inhibitor, and CGP-28238, a specific PGHS-2 inhibitor, reduced fibroblast proliferation in a dose-dependent manner. These drugs also reduced [3H]thymidine incorporation into the DNA of fibroblasts. These effects were correlated with a decrease in prostaglandin (PG) E2 levels in the cell medium. However, piroxicam at doses that selectively inhibit PGHS-1 did not have a significant effect on fibroblast proliferation. Finally, we showed that the antiproliferative effect of dexamethasone and PGHS-2 inhibitors was significantly antagonized when PGE2 was added to the culture medium. Our results suggest that PGHS-2 and prostaglandins such as PGE2 might play an important role in the regulation of 3T6 fibroblast growth stimulated by growth factors of serum.

3T3 Cells↗