Effect of Bakuchiol on Leukocyte Functions and Some Inflammatory Responses in Mice

The effects of bakuchiol, a meroterpenoid isolated from the leaves of Psoralea glandulosa L., on phospholipase A₂ (PLA₂) activity from different sources, human neutrophil responses, zymosan air pouch and topical inflammation in mice, were investigated. This natural product was a weak inhibitor of secretory and intracellular PLA₂ but dose-dependently reduced the formation of LTB₄ and TXB₂ by human neutrophils and platelet microsomes, respectively. In addition, bakuchiol inhibited degranulation in human neutrophils, whereas superoxide generation was not affected. In mice, bakuchiol decreased cell migration, myeloperoxidase activity and eicosanoid levels in the air pouch inflammation induced by zymosan. After topical administration, this compound was effective as an inhibitor of oedema and myeloperoxidase activity in the 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ear oedema and significantly reduced the PGE₂ content and ear oedema in the arachidonic acid-induced response. Bakuchiol is a natural anti-inflammatory agent able to control leukocytic functions such as eicosanoid production, migration and degranulation in the inflammatory site.     

Topical anti-inflammatory phytomedicine based on Sphagneticola trilobata dried extracts

Context: The aerial parts of Sphagneticola trilobata (L.) Pruski (Asteraceae) are popularly used to treat topical inflammation, but have not been fully investigated.

Objective: To identify polar compounds in S. trilobata extracts and develop a new topical phytomedicine based on the kaurenoic acid (KA) content while monitoring and demonstrating its topical anti-inflammatory activity.

Materials and methods: Ethanol spray-dried extract of S. trilobata was analysed by LC-MS while the KA content from semisolid was analysed by LC-UV. The extent of ear edema induced by applying 20?μL of croton oil (2.5%), arachidonic acid (AA; 2?mg/ear) and decanoylphorbol-13-acetate (TPA; 2.5?mg/ear) in mice was used to evaluate the biological activity of the semisolids, which were applied 30?min before the phlogistic agents.

Results: Eight phenylpropanoids and four oleanane-type triterpenoid saponins were identified, majority of them reported for the first time in this species, in addition to KA. The semisolid containing 1.0% of dried extract reduced the ear edema induced by croton oil [77.2?±?4.5%; ID50?=?0.49 (0.28–0.87%)], TPA (81.5?±?2.4%) and AA (39.1?±?6.9%), with decreasing effect at higher KA concentrations. This was accompanied by neutrophil migration inhibition as investigated by biochemical and histological assays.

Discussion and conclusion: The anti-inflammatory effects were (at least in part) due to the interference in protein kinase C (PKC) activation, AA-cascade products and neutrophil migration inhibition, demonstrating the efficacy of the folk topical usage of this plant. The results support the development of a novel topical anti-inflammatory phytomedicine properly standardized to treat inflammatory dermatological diseases.     

Biochemical and pharmacological properties of a new topical anti-inflammatory compound, 9-phenylnonanohydroxamic acid (BMY 30094)

Drugs which block the biosynthesis of leukotrienes and prostaglandins may have potential in the treatment of psoriasis and other skin diseases. The biochemical and anti-inflammatory activity of 9-phenylnonanohydroxamic acid (BMY 30094) is described. BMY 30094 inhibited human neutrophil 5-lipoxygenase with an IC50 of 5.7 microM. BMY 30094 also blocked human platelet cyclooxygenase and lipoxygenase with IC50 values of 15.2 and 15.0 microM, respectively. Topical application of this compound blocked arachidonic acid and 12-O-tetradecanoylphorbol ester-induced mouse skin inflammation with activity comparable to that observed for lonapalene. The topical ED50 for BMY 30094 in the arachidonic acid-induced inflammation model is 2.2 mumoles/ear. In the sub-cutaneous carrageenan sponge assay in rats, BMY 30094 blocked LTB4 and PGE2 production and inhibited neutrophil migration. This compound would be a useful tool to determine the role of arachidonic acid metabolites in the etiology of inflammatory dermatoses.     

The Effect of Caffeic Acid on Wound Healing in Skin-incised Mice

This study was carried out to investigate the wound healing effect of caffeic acid in skin-incised mice. Caffeic acid showed significant effects on anti-inflammatory activity and wound healing, such as myeloperoxidase activity, lipid peroxidation, phospholipase A₂ activity and collagen-like polymer synthesis, in incised-wound tissue. On the other hand, it significantly stimulated collagen-like polymer synthesis in NIH 3T3 fibroblast cells, while inhibited both silica-induced reactive oxygen species generation and melittin-induced arachidonic acid release and PGE₂ production in Raw 264.7 cells, and histamine release in RBL 2H3 cells stimulated by melittin or arachidonic acid. Therefore, caffeic acid appears to have a potent antioxidant and anti-inflammatory effect in cell culture system, which may be related to wound healing in skin-incised mice.     

Dihydrolipoic acid inhibits skin tumor promotion through anti-inflammation and anti-oxidation

α-Lipoic acid (LA) has been intensely investigated as a therapeutic agent for several diseases, including hepatic disorder and diabetic polyneuropathy. However, the effects of LA or its reduced form, dihydrolipoic acid (DHLA), on cancer chemoprevention has never been reported. In the present study, we examined the effects of DHLA/LA on the production of nitric oxide (NO) by inducible NO synthase (iNOS) and the formation of prostaglandin E2 (PGE₂) by cyclooxygenase-2 (COX-2), two important mediators associated with inflammation. DHLA/LA significantly inhibited lipopolysaccharide (LPS)-induced NO and PGE₂ formation in RAW 264.7 cells. Meanwhile, treatment with DHLA/LA suppressed the expression of iNOS protein but, unexpectedly, did not affect or increase the expression of COX-2 protein. The in vivo anti-inflammatory and antitumor-promoting activities were evaluated by a topical 12-O-tetradecanoylphorbol 13-acetate (TPA) application to mouse skin with measurement of edema formation, epidermal thickness and hydrogen peroxide production. DHLA significantly inhibited the priming and activation stages of skin inflammation induced by a double TPA application, by decreasing the inflammatory parameters. Furthermore, DHLA inhibited DMBA (0.3 μmol)/TPA (2.0 nmol)-induced skin tumor formation by reducing the tumor incidence and tumor multiplicity. When applied topically onto the shaven backs of mice prior to TPA, DHLA markedly inhibited the expression of iNOS protein. DHLA also strongly and directly inhibited COX-2 activity. These results suggest that DHLA can be a possible chemopreventive agent in inflammation-associated tumorigenesis.     

Neutrophil migration towards C5a and CXCL8 is prevented by non-steroidal anti-inflammatory drugs via inhibition of different pathways

BACKGROUND AND PURPOSE

Non-steroidal anti-inflammatory drugs (NSAIDs) have been shown to induce PG-independent anti-inflammatory actions. Here, we investigated the role of three different NSAIDs (naproxen, ibuprofen and oxaprozin) on neutrophil responses to CXCL8 and C5a.

EXPERIMENTAL APPROACH

Human neutrophils were isolated from healthy volunteers by dextran and Ficoll-Hypaque density gradients. Neutrophils were pre-incubated with different concentrations (1–100 µM) of NSAIDs or kinase inhibitors. Neutrophil degranulation into supernatants was tested by elisa and zymography. Neutrophil chemotaxis was determined using Boyden chambers. F-actin polymerization was determined by Alexa-Fluor 488-conjugated phalloidin fluorescent assay. Integrin expression was assessed by flow cytometry. The phosphorylation of intracellular kinases was studied by Western blot.

KEY RESULTS

Pretreatment with NSAIDs did not affect neutrophil degranulation, but inhibited neutrophil migration and polymerization of F-actin, in response to CXCL8 and C5a. Pretreatment with different NSAIDs prevented C5a-induced integrin (CD11b) up-regulation, while only ibuprofen reduced CXCL8-induced CD11b up-regulation. Pre-incubation with naproxen or oxaprozin, but not ibuprofen, inhibited the PI3K/Akt-dependent chemotactic pathways. Both endogenous (released in cell supernatants) or exogenous (added to cell cultures) PGE₂ did not affect C5a- or CXCL8-induced activities. Short-term incubation with NSAIDs did not affect neutrophil PGE₂ release.

CONCLUSION AND IMPLICATIONS

Treatment with NSAIDs reduced C5a- and CXCL8-induced neutrophil migration and F-actin polymerization via different mechanisms. Inhibition by ibuprofen was associated with integrin down-regulation, while naproxen and oxaprozin blocked the PI3K/Akt pathway. Both NSAID actions were independent of COX inhibition and PGE₂ release.     

An aqueous pomegranate peel extract inhibits neutrophil myeloperoxidase in vitro and attenuates lung inflammation in mice

Punica granatum peel aqueous extract (PGE) is widely used to treat disorders such as inflammation, ulcers and infections, but its pharmacological target is not known. In this study we investigated the effect of PGE on human neutrophil reactive oxygen species (ROS) production in vitro and on LPS-induced lung inflammation in vivo in mice. Neutrophils were isolated and ROS generation was measured by luminol-amplified chemiluminescence. Superoxide anion generation was detected by the cytochrome c reduction assay. H₂O₂ was detected by DCFH fluorescence assay. Myeloperoxidase (MPO) activity was measured by the tetramethyl benzidine oxidation method. Lung inflammation was induced in mice by LPS instillation. PGE inhibited luminol-amplified chemiluminescence of resting neutrophils and N-formyl-methionyl-leucyl-phenylalanine (fMLF)- or phorbol myristate acetate (PMA)-stimulated neutrophils, in a concentration-dependent manner. PGE had no effect on superoxide anion generation, suggesting that it does not directly inhibit NADPH oxidase activity or activation pathways, or scavenge superoxide anions. PGE did not scavenge H₂O₂ but directly inhibited myeloperoxidase activity in vitro. In vivo studies showed that PGE also attenuated LPS-induced lung inflammation in mice. So this study reveals that PGE inhibits neutrophil MPO activity and attenuates LPS-induced lung inflammation in mice. Inhibition of MPO activity by PGE could explain its anti-inflammatory action.     

Identification of 5-lipoxygenase and microsomal prostaglandin E2 synthase-1 as functional targets of the anti-inflammatory and anti-carcinogenic garcinol

Garcinol (camboginol) from the fruit rind of Guttiferae species shows anti-carcinogenic and anti-inflammatory properties, but the underlying molecular mechanisms are unclear. Here we show that garcinol potently interferes with 5-lipoxygenase (EC 7.13.11.34) and microsomal prostaglandin (PG)E₂ synthase (mPGES)-1 (EC 5.3.99.3), enzymes that play pivotal roles in inflammation and tumorigenesis. In cell-free assays, garcinol inhibited the activity of purified 5-lipoxygenase and blocked the mPGES-1-mediated conversion of PGH₂ to PGE₂ with IC₅₀ values of 0.1 and 0.3 μM, respectively. Garcinol suppressed 5-lipoxygenase product formation also in intact human neutrophils and reduced PGE₂ formation in interleukin-1β-stimulated A549 human lung carcinoma cells as well as in human whole blood stimulated by lipopolysaccharide. Moreover, garcinol interfered with isolated cyclooxygenase (COX)-1 (EC 1.14.99.1, IC₅₀ = 12 μM) and with the formation of COX-1-derived 12(S)-hydroxy-5-cis-8,10-trans-heptadecatrienoic acid and thromboxane B₂ in human platelets. In contrast, neither Ca²⁺-ionophore (A23187)-induced arachidonic acid release in neutrophils nor COX-2 activity in A549 cells or whole blood, measured as formation of 6-keto PGF_1α, or isolated human recombinant COX-2 were significantly affected by garcinol (≤30 μM). Together, the high potency of garcinol to selectively suppress PGE₂ synthesis and 5-lipoxygenase product formation provides a molecular basis for the anti-inflammatory and anti-carcinogenic effects of garcinol and rationalizes its therapeutic use.     

A novel indazolo-triazolo-benzotriazepine exerts anti-inflammatory effects by inhibition of cyclooxygenase-2 activity and nitric oxide synthase-2 expression

We have studied the anti-inflammatory activity of (6-(p-bromophenyl)amino-7-(p-chlorophenyl)indazolo[2',3':1,5]-1,2,4-triazolo[4,3-a]-1,3,5-benzotriazepine (ITB), prepared by solid-phase synthesis. This novel compound reduced the production of nitrite and PGE₂ in RAW 264.7 macrophages stimulated with lipopolysaccharide in a concentration-dependent manner. The first effect was dependent on inhibition of nitric oxide synthase-2 (NOS-2) protein expression although ITB did not modify nuclear factor-B (NF-B)-DNA binding. In addition, this compound inhibited cyclooxygenase-2 (COX-2) activity, which was also observed in aspirin-treated human monocytes. The anti-inflammatory effects of ITB were demonstrated in the carrageenan-induced mouse paw oedema, where this compound inhibited swelling and PGE₂ levels in inflamed paws but not in stomachs, in contrast to the dual COX-1/COX-2 inhibitor indomethacin. Inhibition of COX-2 activity and NOS-2 protein expression was confirmed in vivo using the zymosan-injected mouse air pouch model. These results suggest that synthesis of fused indazolo bis(guanidines) is a useful approach in the search for new anti-inflammatory agents.     

Arzanol, a prenylated heterodimeric phloroglucinyl pyrone, inhibits eicosanoid biosynthesis and exhibits anti-inflammatory efficacy in vivo

Based on its capacity to inhibit in vitro HIV-1 replication in T cells and the release of pro-inflammatory cytokines in monocytes, the prenylated heterodimeric phloroglucinyl α-pyrone arzanol was identified as the major anti-inflammatory and anti-viral constituent from Helichrysum italicum. We have now investigated the activity of arzanol on the biosynthesis of pro-inflammatory eicosanoids, evaluating its anti-inflammatory efficacy in vitro and in vivo. Arzanol inhibited 5-lipoxygenase (EC 7.13.11.34) activity and related leukotriene formation in neutrophils, as well as the activity of cyclooxygenase (COX)-1 (EC 1.14.99.1) and the formation of COX-2-derived prostaglandin (PG)E₂in vitro (IC₅₀ = 2.3–9 μM). Detailed studies revealed that arzanol primarily inhibits microsomal PGE₂ synthase (mPGES)-1 (EC 5.3.99.3, IC₅₀ = 0.4 μM) rather than COX-2. In fact, arzanol could block COX-2/mPGES-1-mediated PGE₂ biosynthesis in lipopolysaccharide-stimulated human monocytes and human whole blood, but not the concomitant COX-2-derived biosynthesis of thromboxane B₂ or of 6-keto PGF_1α, and the expression of COX-2 or mPGES-1 protein was not affected. Arzanol potently suppressed the inflammatory response of the carrageenan-induced pleurisy in rats (3.6 mg/kg, i.p.), with significantly reduced levels of PGE₂ in the pleural exudates. Taken together, our data show that arzanol potently inhibits the biosynthesis of pro-inflammatory lipid mediators like PGE₂in vitro and in vivo, providing a mechanistic rationale for the anti-inflammatory activity of H. italicum, and a rationale for further pre-clinical evaluation of this novel anti-inflammatory lead.     

Assessment of antinociceptive,anti-inflammatory and antioxidant properties of Cymbopogon winterianus leaf essential oil

The present study investigated the antinociceptive, anti-inflammatory and antioxidant effects of the leaf essential oil (LEO) of Cymbopogon winterianus Jowitt (Poaceae). In the acetic acid-induced writhing and formalin tests, the LEO (50, 100, and 200?mg/kg, p.o.) significantly reduced (p?<?0.05) the number of writhings and paw licking times in the first (0-5?min) and second (15-30?min) phases, respectively. In contrast, the LEO did not alter the latency time for mice licking the rear paws in hot-plate test. The LEO inhibited the carrageenan-induced neutrophil migration to the peritoneal cavity in a dose-dependent manner (35.5%, 42.8%, and 66.1% at doses of 50, 100, and 200?mg/kg, respectively, p?<?0.001). Moreover, LEO exhibited higher scavenging activity toward 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals with an IC₅₀ (12.66?±?0.56 μg/mL). Our present results demonstrated that the LEO has antinociceptive, anti-inflammatory, and antioxidant properties.     

Comparative study of anti-inflammatory and ulcerogenic activities of different cyclo-oxygenase inhibitors

The aim of the present work was to study the in vivo anti-inflammatory activity of six NSAIDs, ibuprofen, diclofenac, nimesulide, meloxicam, celecoxib and rofecoxib, using the rat air-pouch model of inflammation to characterize the ability of these drugs to induce gastric damage and PGE₂ inhibition. Selective compounds were observed to have no ulcerogenic properties at anti-inflammatory doses; however, these drugs were weaker inhibitors of several inflammatory aspects such as cell influx and exudate formation. In contrast, the non-selective and preferential compounds present anti-inflammatory properties at lower doses than presented by selective drugs. At anti-inflammatory doses, only meloxicam and ibuprofen produced gastric damage and inhibition of PGE₂ synthesis, suggesting that ulcerogenic properties of NSAIDs cannot be predicted by their selectivity index, since meloxicam demonstrates ulcerogenic properties despite its preferential profile.     

Lectin extracted from Canavalia grandiflora seeds presents potential anti-inflammatory and analgesic effects

Neutrophil migration is responsible for tissue damage observed in inflammatory diseases and is also implicated in inflammatory nociception. The use of lectins has been demonstrated to be effective in different activities including anti-inflammatory, antimicrobial, and in cancer therapy. In this study, we addressed the potential use of a lectin from Canavalia grandiflora seeds (ConGF) to control neutrophil migration and inflammatory hypernociception. Pretreatment of the animals intravenously (15 min before) with ConGF inhibited neutrophil migration to the peritoneal cavity in a dose-dependent fashion confirmed by an inhibition of rolling and adhesion of leukocytes by intravital microscopy. Another set of experiments showed that pretreatment of the animals with ConGF inhibited the mechanical hypernociception in mice induced by the i.pl. injection of carrageenan or formalin. This anti-nociceptive effect correlated with an effective blockade of neutrophil influx, as assessed by the hind paw tissue myeloperoxidase levels. Furthermore, ConGF had important inhibitory effects on the mouse carrageenan-induced paw edema. In addition, animals treated with ConGF showed inhibition of cytokines release. In conclusion, we demonstrated that the lectin ConGF inhibits neutrophil migration and mechanical inflammatory hypernociception.     

Lonchocarpus sericeus lectin decreases leukocyte migration and mechanical hypernociception by inhibiting cytokine and chemokines production

In this study, we tested the potential use of a lectin from Lonchocarpus sericeus seeds (LSL), to control neutrophil migration and inflammatory hypernociception (decrease of nociceptive threshold). Pretreatment of the animals intravenously (15 min before) with LSL inhibited neutrophil migration to the peritoneal cavity in a dose-dependent fashion confirmed by an inhibition of rolling and adhesion of leukocytes by intravital microscopy. We also tested the ability of the pretreatment with LSL to inhibit neutrophil migration on immunised mice, and it was observed that a strong inhibition of neutrophil migration induced by ovoalbumin in immunized mice. Another set of experiments showed that pretreatment of the animals with LSL, inhibited the mechanical hypernociception in mice induced by the i.pl. injection of OVA in immunized mice and of carrageenan in naïve mice, but not that induced by prostaglandin E₂ (PGE₂) or formalin. This anti-nociceptive effect correlated with an effective blockade of neutrophil influx, as assessed by the hind paw tissue myeloperoxidase levels. In addition, we measured cytokines (TNF-α and IL-1β) and chemokines (MIP-1α [CCL3] and KC [CXCL1]) from the peritoneal exudates and i.pl. tissue. Animals treated with LSL showed inhibition of cytokines and chemokines release in a dose-dependent manner. In conclusion, we demonstrated that the inhibitory effects of LSL on neutrophil migration and mechanical inflammatory hypernocicepetion are associated with the inhibition of the production of cytokines and chemokines.     

A study of the mechanisms underlying the anti-inflammatory effect of ellagic acid in carrageenan-induced paw edema in rats

Objectives:Ellagic acid (EA) has shown antinociceptive and anti-inflammatory effects. Inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2) enzymes and also cytokines play a key role in many inflammatory conditions. This study was aimed to investigate the mechanisms involved in the anti-inflammatory effect of EA.Results:The results showed that intraplantar injection of carrageenan led to time-dependent development of peripheral inflammation, which resulted in a significant increase in the levels of tumor necrosis factor α (TNF-α) and interleukin 1 (IL-1) β, nitric oxide (NO) and prostaglandin E₂ (PGE₂) and also iNOS and COX-2 protein expression in inflamed paw. However, systemic administration of EA (1–30 mg/kg, intraperitoneal [i.p.]) could reduce edema in a dose-dependent fashion in inflamed rat paws with ED50 value 8.41 (5.26–14.76) mg/kg. It decreased the serum concentration of NO, PGE₂, aspartate aminotransferase and alanine aminotransferase, and suppress the protein expression of iNOS, COX-2 enzymes, and attenuated the formation of PGE_2, TNF-α and IL-1 β in inflamed paw tissue. We also demonstrated that EA significantly decreased the malondialdehyde (MDA) level in liver at 5 h after carrageenan injection. Moreover, histopathological studies indicated that EA significantly diminished migration of polymorphonuclear leukocytes into site of inflammation, as did indomethacin.Conclusions:Collectively, the anti-inflammatory mechanisms of EA might be related to the decrease in the level of MDA, iNOS, and COX-2 in the edema paw via the suppression of pro-inflammatory cytokines (TNFα, IL1 β), NO and PGE₂ overproduction.KEY WORDS: Carrageenan, ellagic acid, inducible nitric oxide synthase, prostaglandin E₂, Rat     

The synovial prostaglandin system in chronic inflammatory arthritis: differential effects of steroidal and nonsteroidal anti-inflammatory drugs

1 The present study was undertaken to characterize the spectrum of arachidonic acid metabolites present in synovial effusions of patients with rheumatoid or psoriatic arthritis, and to compare changes in their concentration following a short-term treatment with 6α-methyl-prednisolone (6-MeP: 4-8 mg/day) or indoprofen (1.2 g/day), a nonsteroidal anti-inflammatory agent with proven synovial prostaglandin inhibitory effect.

2 Measurements of prostaglandin E₂ (PGE₂), thromboxane (TX) B₂, 6-keto-PGF_1α and PGF_2α were performed by radioimmunoassay techniques in synovial effusions obtained from 23 patients, and validated by thin-layer chromatographic analysis of the extracted immunoreactivity.

3 PGE₂ and TXB₂ accounted for more than 60% of the total immunoreactivity in untreated patients. The absence of any constant ratio between the different arachidonic acid metabolites detected in synovial fluid is consistent with a heterogeneous cellular origin of these compounds.

4 Indoprofen treatment was associated with a consistent reduction of synovial prostaglandin and thromboxane concentrations, ranging from 36% in the case of 6-keto-PGF_1α to 90% in the case of PGE₂.

5 In contrast, 6-MeP caused opposite changes on different metabolites originating via the cyclo-oxygenase pathway. Thus, 6-keto-PGF_1α concentrations were reduced by 35%, PGF_2α concentrations were increased by 30%, while PGE₂ and TXB₂ were unchanged following 6-MeP.

6 Although the mechanism(s) underlying the failure of 6-MeP to reduce synovial PGE₂ and TXB₂ levels are uncertain, the results of the present study clearly indicate that therapeutic doses of steroidal and nonsteroidal anti-inflammatory drugs cause quite distinct changes in arachidonic acid metabolism, which might be relevant to their specific therapeutic actions and side-effects.

     

In vivo anti-inflammatory properties of aerial parts of Nasturtium officinale

Context: Nasturtium officinale R. Br. (watercress) has long been used in Iranian folk medicine to treat hypertension, hyperglycemia, and renal colic. Moreover, anticancer, antioxidant, and hepatoprotective properties of N. officinale have been reported.

Objective: In this study, anti-inflammatory activity of the hydro-alcoholic extract from aerial parts of N. officinale was investigated.

Materials and methods: Oral administration of the hydro-alcoholic extract of N. officinale (250, 500 and 750?mg?kg^?1) was investigated on two well-characterized animal models of inflammation, including carrageenan- or formalin-induced paw edema in rats. Then, the topical anti-inflammatory effect of N. officinale (2 and 5?mg/ear) was studied on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema. Finally, biopsy of the paw or ear was performed for pathological evaluation.

Results: Acute toxicity tests of N. officinale in rats established an oral LD₅₀ of >5?g?kg^?1. The extract of watercress (250, 500 and 750?mg?kg^?1) significantly inhibited carrageenan-induced paw edema 1, 2, 3 and 4?h after carrageenan challenge (p??1) also showed considerable activity against formalin-evoked paw edema over a period of 24?h (p?N. officinale (5?mg/ear) reduced TPA-induced ear edema (p?Discussion and conclusion: Our findings indicate potent anti-inflammatory activity of N. officinale in systemic and topical application and propose its potential as an anti-inflammatory agent for treatment of inflammatory conditions.     

Lipoxins and novel 15-epi-lipoxin analogs display potent anti-inflammatory actions after oral administration

1. Lipoxins (LX) and aspirin-triggered 15-epi-lipoxins (ATL) exert potent anti-inflammatory actions. In the present study, we determined the anti-inflammatory efficacy of endogenous LXA(4) and LXB(4), the stable ATL analog ATLa2, and a series of novel 3-oxa-ATL analogs (ZK-996, ZK-990, ZK-994, and ZK-142) after intravenous, oral, and topical administration in mice. 2. LXA(4), LXB(4), ATLa2, and ZK-994 were orally active, exhibiting potent systemic inhibition of zymosan A-induced peritonitis at very low doses (50 ng kg(-1)-50 microg kg(-1)). 3. Intravenous ZK-994 and ZK-142 (500 microg kg(-1)) potently attenuated hind limb ischemia/reperfusion-induced lung injury, with 32+/-12 and 53+/-5% inhibition (P<0.05), respectively, of neutrophil accumulation in lungs. The same dose of ATLa2 had no significant protective action. 4. Topical application of ATLa2, ZK-994, and ZK-142 ( approximately 20 microg cm(-2)) prevented vascular leakage and neutrophil infiltration in LTB(4)/PGE(2)-stimulated ear skin inflammation. While ATLa2 and ZK-142 displayed approximately equal anti-inflammatory efficacy in this model, ZK-994 displayed a slower onset of action. 5. In summary, native LXA(4) and LXB(4), and analogs ATLa2, ZK-142, and ZK-994 retain broad anti-inflammatory effects after intravenous, oral, and topical administration. The 3-oxa-ATL analogs, which have enhanced metabolic and chemical stability and a superior pharmacokinetic profile, provide new opportunities to explore the actions and therapeutic potential for LX and ATL.     

Comparison of cyclooxygenase inhibitory activity and ocular anti-inflammatory effects of ketorolac tromethamine and bromfenac sodium

ABSTRACT

Objective: To compare the cyclooxygenase (COX) activity and anti-inflammatory effects of the nonsteroidal anti-inflammatory drugs (NSAIDs) ketorolac tromethamine (ketorolac) and bromfenac sodium (bromfenac).

Methods: Cyclooxygenase activity and selectivity was determined in vitro by measuring prostaglandin E₂ (PGE₂) production following incubation of varying concentrations of NSAID with human recombinant COX‐1 or COX‐2 and arachidonic acid. Anti-inflammatory effects were evaluated in a rabbit model in which an ocular inflammatory response was induced by intravenous injection of 10?µg/kg lipopolysaccharide (LPS). In study animals, one eye was treated with 50?µL (+/–) ketorolac 0.4% (Acular LS) or bromfenac 0.09% (Xibrom) and the other eye with 50?µL buffered saline. In control animals, both eyes were treated with vehicle. All animals were treated twice: 2 hours and 1 hour before LPS.

Main outcome measures: PGE₂ production in vitro, measured by enzyme immunoassay; fluorescein isothiocyanate (FITC)-dextran leakage into the anterior chamber, measured by fluorophotometry; aqueous PGE₂ levels in vivo, measured by ELISA immunoassay.

Results: Ketorolac was six times more active against COX‐1 (?IC₅₀ = 0.02?µM) than COX‐2 (?IC₅₀ = 0.12?µM) while bromfenac was ≈ 32 times more active against COX‐2 (?IC₅₀ = 0.0066?µM) than COX‐1 (?IC₅₀ = 0.210?µM). In the animal model, both drugs resulted in nearly complete inhibition of FITC-dextran leakage and PGE₂ production in the anterior chamber of treated eyes. There was also a 79% inhibition (?p < 0.001) of FITC-dextran leakage in the contralateral eyes of bromfenac-treated rabbits, and a 22.5% inhibition (not statistically significant) in the contralateral eyes of ketorolac-treated rabbits.

Conclusions: Ketorolac is relatively COX‐1 selective while bromfenac is potently selective for COX‐2 over COX‐1. In the animal model, both ketorolac 0.4% and bromfenac 0.09% demonstrated maximal anti-inflammatory activity in treated eyes. Only bromfenac 0.09% had a significant effect on the contralateral eye, suggesting possible systemic absorption of this drug.     

Chemical study and anti-inflammatory, analgesic and antioxidant activities of the leaves of Aristotelia chilensis (Mol.) Stuntz, Elaeocarpaceae

Objectives Aristotelia chilensis leaves (Elaeocarpaceae) are used in Chilean folk medicine to treat pain and inflammation. A bioguided study was carried out on serial extracts (hexane, dichloromethane, methanol, aqueous extract (INFU) and a crude mixture of alkaloids (ALK‐MIX). All extracts were evaluated for (1) topical administration against both arachidonic acid and 12‐deoxyphorbol‐13‐decanoate (TPA)‐induced inflammation in mice and (2) per‐os administration against inflammation by λ‐carrageenan‐induced paw oedema in guinea‐pigs and (3) topical analgesia in tail flick and formalin models and per‐os writhing test in mice. Methods Greater anti‐inflammatory effects were obtained against TPA with dichloromethane extract and methanol extract (63.9 and 66.0%, respectively). INFU showed the most potent effect (56.2%) against arachidonic acid. Greater effects were obtained in the writhing test with hexane and dichloromethane extracts (89.2% both). In the topical analgesia models, all the extracts and ALK‐MIX were active with exception of the hexane extract in the formalin assay. In tail flick test, ALK‐MIX and the methanol extract were the most active (58.2 and 55.2%, respectively). In relation to the tail formalin assay, the methanol extract (74.1%) was the most active. Concerning antioxidant activity, both INFU and the methanol extract were the most active either in the inhibition of xanthine oxidase (52.9 and 62.7%, respectively) or in the DPPH free radical scavenging activity (EC50 (concentration that produced 50% of activity) = 12.1 and 9.7 µg/ml, respectively). Key findings Aristoteline, aristone, serratoline and hobartinol were isolated from ALK‐MIX. Ursolic acid, friedelin and quercetin 5,3′‐dimethyl ether were present in the dichloromethane extract while quercetin 3‐O‐β‐d ‐glucoside and kaempferol were present in the methanol extract. From INFU were isolated protopine, aristoteline and caffeic and ferulic acids. Conclusions The effects of A. chilensis are herein demonstrated, validating its use in traditional medicine. Protopine is reported for the first time in Elaeocarpaceae.