The annonalide diterpene extracted from Casimirella ampla (Miers) reduces inflammatory and antinociceptive events in general models of inflammation.

ETHNOPHARMACOLOGICAL RELEVANCE: The plants of the genus Casimirella ampla (Miers) (C. ampla) are extensively used in folk medicine. For a long time, rural communities have been using extracts from its roots for food and therapeutic purposes. The extract is rich in diterpenoid annonalide (Annona), which has antiophidic, anti-inflammatory and antinociceptive properties. Inflammation is the body's primary defense mechanism against cell damage and invasion by pathogens, which can trigger acute and chronic inflammatory processes. The first line of treatment for this condition consists of the use of non-steroidal anti-inflammatory drugs, but these have numerous associated collateral damages, based on scientific knowledge about diterpenoids from C. ampla, as well as their already reported antinociceptive and anti-inflammatory properties. AIMS OF THE STUDY: Evaluate the effect of Annona in classic models of inflammation and pain. MATERIALS AND METHODS: Animals were pretreated with Annona (0.1, 1.0 and 10 mg/kg), or Tween 80 (2%), or indomethacin (Indo) (10 mg/kg) orally in the paw edema tests induced by carrageenan (Cg), serotonin (5-HT), histamine, bradykinin, 48/80 and, prostaglandin E2 (PGE2), evaluating microscopic lesion scores, migration of leukocytes to the peritoneal cavity, concentration of myeloperoxide (MPO), malonyldialdehyde (MDA) and glutathione (GSH), abdominal contortion test by acetic acid and formalin test. RESULTS: Treatment with Annona compound at a dose of 0.1 mg/kg was more effective in reducing inflammatory, oxidant and nociceptive parameters, as it reduced paw edema induced by carrageenan, through different mediators and migration of inflammatory cells. Furthermore, it worked by reducing the concentration of MPO, MDA, preserving GSH levels and reducing nociception caused by formalin and acetic acid.

Photobiomodulation exerts anti-inflammatory effects on the vascular and cellular phases of experimental inflammatory models.

Photobiomodulation therapy (PBMT) is a non-thermal therapeutic procedure widely used in clinical practice. It is considered an effective modality of treatment for the control of various inflammatory conditions with fewer adverse effects as compared to conventional therapy. However, despite the clinical effects, the mechanisms of action and dosimetric parameters of PBMT are not fully understood. This study was performed to describe the effects of two different doses of PBMT on experimental models of inflammation. Male Swiss mice were administered with 0.9% of saline or phlogistic agents (carrageenan, dextran, serotonin, histamine, or bradykinin) by intra-plantar injection and were treated with PBMT at a dose of 1 or 5 J/cm2; right after, the variation of the paw volume was made, and histopathological analysis and myeloperoxidase assay of the carrageenan-induced edematous paw tissues were performed. The action of PBMT on carrageenan-induced vascular permeability was further evaluated. Our results showed that PBMT (1 J/cm2) led to an improvement in paw edema induced by the phlogistic agents and further reduced the histological scores. Inhibition of neutrophil migration was observed following the administration of 1 and 5 J/cm2 of PBMT. However, only 1 J/cm2 of PBMT showed beneficial effects on carrageenan-induced edema. Laser at a dose of 1 J/cm2 showed cellular and vascular effects since it was able to reverse all the inflammatory parameters, and laser at a dose of 5 J/cm2 probably has only cellular effects in the presence of acute inflammation.

Food restriction reduces hepatic alterations associated with experimental periodontitis.

BACKGROUND: Periodontitis is a chronic inflammatory and multifactorial disease that affects the periodontal structures and can cause alterations in the hepatic tissue. The aim of the present study was to evaluate whether a diet with food restriction can decrease oral and liver alterations associated with ligature-induced periodontitis. METHODS: Twenty-four female Wistar rats were used in this study, randomized into three groups (n = 8 for each group): control (regular food); periodontitis (regular food + periodontitis induced with ligatures); and food restriction (diet with food restriction and periodontitis induction). The following periodontium parameters were analyzed tooth mobility (TM), probing pocket depth (PPD), gingival bleeding index (GBI), and alveolar bone height (ABH). In the liver, the levels of oxidative stress markers-malondialdehyde (MDA), glutathione (GSH), total cholesterol, and levels of myeloperoxidase (MPO) activity were measured. Liver samples were analyzed for histopathological score. In the blood tissue, the levels of enzymes alanine aminotransferase (ALT), aspartate aminotransferase (AST), glucose, total cholesterol, and the high-density lipoprotein (HDL) were also evaluated. RESULTS: The animals that received a diet with food restriction + periodontitis showed a decrease in hepatic histopathological score (P < 0.05) when compared with the periodontitis group, the same for glucose, total cholesterol, ALT, AST, and ABH data. The group with food restriction + periodontitis showed a decrease in the histopathological liver score (P < 0.05) compared with the group with periodontitis. CONCLUSION: This study revealed that food restriction reduced oral damages, as well as hepatic, blood and alveolar bone alterations associated with ligature-induced periodontitis in rats.

Phosphatidylinositol 3-kinase gamma participates in nimesulide-induced hepatic damage.

OBJECTIVE: To evaluate the participation of the phosphatidylinositol 3-kinase pathway in the liver damage caused by nimesulide. METHODS: Liver damage been induced by nimesulide. Mice were treated with either 2% dimethyl sulfoxide or AS605240, a phosphatidylinositol 3-kinase gamma pathway antagonist. Blood samples were collected for function assays of liver. The liver was removed for analysis of liver weight/animal weight ratio, histopathological parameters, oxidative and nitrous stress, cytokine levels, and the immunostaining for cyclooxygenase 2 and nuclear factor kappa B. KEY FINDINGS: Liver injured by nimesulide and treated with phosphatidylinositol 3-kinase gamma inhibitor significantly reversed (P < 0.05) the damage; it decreased the liver weight/animal weight ratio, histopathological scores, and neutrophil infiltration, consequently reducing oxidative stress. In addition, we show that phosphatidylinositol 3-kinase gamma is associated with hepatic damage induced by nimesulide, because it altered liver function and increased the protein immunostaining of cyclooxygenase 2 and nuclear factor kappa B in the liver tissue of nimesulide-treated animals. CONCLUSIONS: The findings from the present study allows us to infer that nimesulide causes liver damage through the phosphatidylinositol 3-kinase gamma pathway.

Lectin from red algae Amansia multifida Lamouroux: Extraction, characterization and anti-inflammatory activity.

Seaweed lectins are very promising biotechnological tools that also gain prominence when applied to the pharmacology field. The purpose of the present work was to isolate and characterize lectin from the red algae Amansia multifida and subsequently test it in general inflammation models. The lectin was purified by ion exchange chromatography, characterized with two-dimensional electrophoresis, automated analysis of amino acid sequences and circular dichroism spectroscopy. The pharmacological tests performed were paw edema induced by carrageenan or rapid inflammatory mediators, peritonitis induced by carrageenan and myeloperoxidase leukocyte count assays, glutathione and cytokine concentration. Our results have identified a 30 KDa molecular weight protein that presents a major secondary structure arranged in ß-strand elements (~43%). A fragment of 20 amino acid residues was sequenced and presented low identity to the known classes of lectins from marine alga. This lectin was able to modulate inflammatory parameters such as paw edema, leukocyte migration, oxidative stress and proinflammatory cytokines. Thus, the lectin from the seaweed Amansia multifida has evident anti-inflammatory properties because it acts by reducing the formation of edema by modulating the effect of vascular mediators, migration of neutrophils, proinflammatory cytokines and oxidative stress control.

Chemical structure, anti-inflammatory and antinociceptive activities of a sulfated polysaccharide from Gracilaria intermedia algae.

The present work aimed at carrying out the isolation and biochemical characterization of a sulfated polysaccharide fraction (PLS) from the marine algae Gracilaria intermedia and investigating its anti-inflammatory and antinociceptive potential. PLS was obtained through enzymatic digestion with papain and analyzed by means of gel permeation chromatography and Nuclear Magnetic Resonance to 1H and 13C. In order to evaluate the potential of anti-inflammatory action of PLS, we performed paw edema induced by carrageenan, dextran, compound 48/80, histamine and serotonin. In addition, we also measured the concentration of myeloperoxidase, cytokines, the count of inflammatory cells and performed tests of the nociception. The PLS isolated was of high purity and free of contaminants such as proteins, and had molecular weight of 410 kDa. The same macromolecule was able to decrease the paw edema induced by all inflammatory agents (P < 0.05), myeloperoxidase (MPO) activity, neutrophil migration and IL-1ß levels. It also decreased acetic acid-induced writhing (P < 0.05) and formalin-induced paw licking time (P < 0.05), but no in hot plate test. In summary, the PLS decreased the inflammatory response by reducing neutrophil migration and modulating IL-1ß production and antinociceptive effects by a peripheral mechanism dependent on the down-modulation of the inflammatory mediators.

Gabapentin attenuates intestinal inflammation: Role of PPAR-gamma receptor.

Gabapentin is an anticonvulsant drug that is also used for post-herpetic neuralgia and neuropathic pain. Recently, gabapentin showed anti-inflammatory effect. Nuclear factor kappa B (NFκB) is a regulator of the inflammatory process, and Peroxisome Proliferator-activated Receptor gamma (PPAR-gamma) is an important receptor involved in NFκB regulation. The aim of the present work was to study the potential role of PPAR-gamma receptor in gabapentin-mediated anti-inflammatory effects in a colitis experimental model. We induced colitis in rats using trinitrobenzenosulfonic acid and treated them with gabapentin and bisphenol A dicyldidyl ether (PPAR-gamma inhibitor). Macroscopic lesion scores, wet weight, histopathological analysis, mast cell count, myeloperoxidase, malondialdehyde acid, glutathione, nitrate/nitrite, and interleukin levels in the intestinal mucosa were determined. In addition, western blots were performed to determine the expression of Cyclooxygenase-2 (COX-2) and NFκB; Nitric Oxide Inducible Synthase (iNOS) and Interleukin 1 beta (IL-1ß) levels were also determined. Gabapentin was able to decrease all inflammatory parameters macroscopic and microscopic in addition to reducing markers of oxidative stress and cytokines such as IL-1ß and Tumor Necrosis Factor alpha (TNF-α) as well as enzymes inducible nitric oxide synthase and cyclooxygenase 2 and inflammatory genic regulator (NFκB). These effect attributed to gabapentin was observed to be lost in the presence of the specific inhibitor of PPAR-gamma. Gabapentin inhibits bowel inflammation by regulating mast cell signaling. Furthermore, it activates the PPAR-gamma receptor, which in turn inhibits the activation of NFκB, and consequently results in reduced activation of inflammatory genes involved in inflammatory bowel diseases.

Polysaccharides derived from Morinda citrifolia Linn reduce inflammatory markers during experimental colitis.

ETHNOPHARMACOLOGICAL RELEVANCE: There are many reports of pharmacological activities of extracts and fractions of different vegetable-derived products in the scientific literature and in folk medicine. Ethnopharmacological use of these products by various communities continues to be extensively explored, and they account for more than half of all medications used worldwide. Polysaccharides (PLS) extracted from plants such as Morinda Citrifolia Linn present therapeutic potential in treatment of inflammatory bowel diseases (IBD) such as ulcerative colitis (UC). AIM OF THE STUDY: To evaluate the anti-inflammatory action of Noni-PLS against the intestinal damage in UC induced by acetic acid in mice. MATERIALS AND METHODS: In acetic acid-induced colitis, the mice were treated intraperitoneally (ip) with Noni-PLS (0.1, 0.3, and 3.0 mg/kg) or subcutaneously (sc) with dexamethasone (2.0 mg/kg) 30 min before euthanasia to determine the best dose of Noni-PLS with an anti-inflammatory effect in the course of UC. The colonic tissue samples were collected for macroscopic, wet weight, microscopic and biochemical (myeloperoxidase (MPO), glutathione (GSH), malondialdehyde (MDA), nitrate/nitrite (NO3/NO2), cytokines, cyclooxygenase (COX-2) and inducible nitric oxide (iNOS)) analyses. RESULTS: Treatment with Noni-PLS reduced the intestinal damage induced by acetic acid as it reduced macroscopic and microscopic scores and the wet weight of the colon. In addition, MPO activity and levels of GSH, MDA, NO3/NO2, pro-inflammatory cytokines, and COX-2 expression reduced. CONCLUSIONS: This study suggests that Noni-PLS exhibits anti-inflammatory action against intestinal damage by reducing inflammatory cell infiltration, oxidative stress, pro-inflammatory action of cytokines, COX-2 and iNOS expression in the inflamed colon. Noni-PLS shows therapeutic potential against inflammatory disorders like UC.

Proteins from Plumeria pudica latex exhibit protective effect in acetic acid induced colitis in mice by inhibition of pro-inflammatory mechanisms and oxidative stress.

Latex proteins from P. pudica (LPPp) have anti-inflammatory activity. In the present study, LPPp was evaluated to protect animals against inflammatory ulcerative colitis (UC). UC was induced by intracolonic instillation of a 6% acetic acid solution and the animals received LPPp (10, 20 or 40 mg/kg) by intraperitoneal route 1 h before and 17 h after acetic acid injection. Eighteen hours after instillation of acetic acid, the mice were euthanized and the colons were excised to determine the wet weight, macroscopic and microscopic lesion scores, myeloperoxidase (MPO) activity, IL1-ß levels, glutathione (GSH) and malondialdehyde (MDA) concentration and superoxide dismutase (SOD) activity. The results revealed that LPPp treatment (40 mg/kg) had a protective effect on acetic acid-induced colitis by reducing the wet weight, macroscopic and microscopic scores of intestinal lesions and colonic MPO activity. Additionally, LPPp inhibited tissue oxidative stress, since decreases in GSH consumption, MDA concentration and SOD activity were observed. The treatment with LPPp reduced the levels of cytokine IL-1ß, contributing to the reduction of colon inflammation. Biochemical investigation showed that LPPp comprises a mixture of proteins containing proteinases, chitinases and proteinase inhibitors. These data suggest that LPPp has a protective effect against intestinal damage through mechanisms that involve the inhibition of inflammatory cell infiltration, cytokine release and oxidative stress.

Sulfated polysaccharides from the marine algae Gracilaria caudata prevent tissue damage caused by ligature-induced periodontitis.

Sulfated polysaccharides (PLS) extracted from the marine algae of the genus Gracilaria showed biological activity in different inflammatory models, except for periodontitis. Thus, this study aimed to evaluate the effectiveness of the treatment with PLS from Gracilaria caudata in ligature-induced periodontitis. 40 animals distributed into 5 groups were used (the control group (unligated), the ligated untreated group, and the ligated groups treated with 2.5, 5.0 and 10.0 mg/kg of PLS with intraperitoneal injection, respectively). After 20 days of treatment, the animals were killed and the following parameters were evaluated: Gingival Bleeding Index (GBI), Probing Pocket Depth (PPD), Myeloperoxidase (MPO) activity, Alveolar Bone Loss (ABL) for periodontal tissues; histopathological examination of gingival and liver tissues (Steatosis score); glutathione and malondialdehyde concentrations in the liver, serum levels of alanine aminotransferase and aspartate aminotransferase. The data revealed that treatment with 2.5 mg/kg of PLS showed the best anti-inflammatory effects with reduction of GBI, PPD and MPO activity, as well as oxidative stress and steatosis in liver. Our results indicated that the adjunct treatment with PLS from Gracilaria caudata could prevent the periodontal and hepatic tissue alteration caused by periodontitis.

Chemical structure and anti-inflammatory effect of polysaccharide extracted from Morinda citrifolia Linn (Noni).

Polysaccharides extracted from plants are very promising molecules in the field of pharmacotherapy. Knowing this, the aim of this study was to extract, characterize and evaluate the action of the polysaccharide of Morinda citrifolia Linn (Noni-PLS) in biological models of inflammatory processes. The characterization tests shown that sample refers to a heteropolysaccharide composed mainly of homogalacturonan and rhamnogalacturonan. This polysaccharide at dose of 10 mg/kg, when tested in our models of inflammation, showed significant activity in reducing carrageenan-induced paw oedema as well as all mediators edemas. This polysaccharide was able to inhibit the migration of leukocytes to the site of inflammation, and still reduced inflammatory nociception tests. This results, allows us to conclude that the polysaccharide extracted from Morinda citrifolia linn has anti-inflammatory potential since it reversed inflammatory parameters such as edema, leukocyte migration and nociception.

Photobiomodulation reduces neutrophil migration and oxidative stress in mice with carrageenan-induced peritonitis.

The purpose of the study is to investigate the effects of two doses of photobiomodulation (PBM) on inflammatory parameters including cell migration and oxidative stress in carrageenan-induced peritonitis models. Twenty-eight mice were divided into four groups: saline; untreated carrageenan (Cg; inflammation induced); and PMB treatment groups L1 and L5 (inflammation induced with carrageenan followed by laser irradiation at 1 and 5 J/cm2, respectively). After 30 min of inducing inflammation, laser irradiation was administered every hour, for 4 h. Peritoneal fluid was collected for analyses. The total leukocyte number in the peritoneal fluid in L1 (4.33 ± 2.34) and L5 (4.95 ± 2.86) after PBM was lower than that in Cg (10.93 ± 5.15 cells/ml). The average differential count of neutrophils in the Cg was 9.46 ± 4.31 cells/ml, which was higher than that in L1 (3.7 ± 2.08) and L5 (4.94 ± 2.57). Myeloperoxidase activity was also lower in L1 (1.89 ± 0.43) and L5 (4.84 ± 2.62) than in Cg (22.92 ± 4.52 UMPO/ml). Malondialdehyde content was lower in L1 (137.5 ± 12.33) and L5 (169.6 ± 22.77) than in Cg (345.7 ± 65.67 nmol/ml). Glutathione peroxidase concentration was significantly higher in L1 (155.2 ± 12.43) and L5 (145.9 ± 9.585) than in Cg (79.75 ± 9.567 µ/ml). Nitrite concentration was lower in L1 (0.3317 µM ± 0.0669) and L5 (0.2429 µM ± 0.0232) than in Cg (0.8380 µM ± 0.01615). Laser irradiation at 1 and 5 J/cm2 reversed the inflammation (as indicated by neutrophil infiltration and oxidative stress).

Epiisopiloturine, an imidazole alkaloid, reverses inflammation and lipid peroxidation parameters in the Crohn disease model induced by trinitrobenzenosulfonic acid in Wistar rats.

Epiisopiloturine (EPI) is an important imidazole alkaloid because of its pharmacological properties. The aim of this study was to investigate the effects of epiisopiloturine on inflammatory parameters of the colonic mucosa in a rat model of Crohn's disease (CD). For this, we induced colitis using trinitrobenzenosulfonic acid and determined myeloperoxidase (MPO), interleukin 1 ß (IL-1ß), glutathione (GSH), and malondialdehyde (MDA) levels in the intestinal mucosa. The location and expression of the inflammatory markers in the colon were investigated by immunohistochemistry for NO synthase induced (iNOS), interleukin 1 beta (IL-1ß), and cyclooxygenase-2 (COX-2) and western blotting (iNOS and COX-2), respectively. Compared with TNBS alone, epiisopiloturine at 1 mg/kg reduced the macroscopic and microscopic scores, wet weight of the colon, and neutrophilic infiltration and expression of the pro-inflammatory cytokine IL-1ß. Epiisopiloturine at 1 mg/kg maintained or restored GSH levels and simultaneously decreased MDA levels. Animals treated with epiisopiloturine exhibited reduced immunostaining for IL-1ß, iNOS, and COX-2 and reduced cell count per field. Epiisopiloturine reduced the expression of COX-2 and iNOS in the colon. Based on these findings, we conclude that epiisopiloturine at 1 mg/kg may be an important pharmacological tool against intestinal inflammatory diseases due to its inhibitory action on key enzymes and products involved in inflammation.

Lectin obtained from the red seaweed Bryothamnion triquetrum: Secondary structure and anti-inflammatory activity in mice.

Seaweeds are sources of biomolecules with biological activities and pharmacological potential - for example, lectins, a group of proteins that can bind reversibly to carbohydrates or compounds containing them. The aim of this study was to elucidate the structural properties of a lectin extracted from the red seaweed Bryothamnion triquetrum (BtL) and to investigate its anti-inflammatory activity in mice. The lectin was purified by precipitation with ammonium sulfate and ion-exchange chromatography. Its secondary structure and tryptophan (Trp) microenvironment were analyzed by circular dichroism spectroscopy and steady-state fluorescence spectroscopy, respectively. The anti-inflammatory effect was evaluated by means of paw edema induced by carrageenan or dextran, myeloperoxidase activity in paw tissue, and by measurement of leukocyte and neutrophil migration and cytokine quantification in a peritonitis model. The secondary structure of BtL is mostly composed of ß-strands and unordered conformation, and it is quite resistant to extremes of pH and temperature, preserving the exposure of Trp residues under these conditions. In an assessment of biological activities, groups of mice were subjected to pretreatment with BtL before the inflammatory stimulus. BtL had anti-inflammatory effects in the models tested, and hence may be considered a molecule with potential to be used in the pharmaceutical industry.

The anti-inflammatory and antinociceptive activity of albumins from Crotalaria retusa seeds.

Seeds of Crotalaria retusa L. are used in popular medicine because of their pharmacological properties. The albumin fraction obtained from its seeds contains lectin, a protein known to have analgesic and anti-inflammatory properties. Thus, albumins extracted from C. retusa were investigated for their anti-inflammatory and antinociceptive effects. The intraperitoneal administration of different doses of albumins (5, 10 or 20mg/kg) significantly inhibited the mice paw edema induced by carrageenan (maximum inhibition rate of 80.9% at four hours, 20mg/kg), and this event was followed by diminishing paw myeloperoxidase measurements. Albumins (20mg/kg) also inhibited neutrophil migration into the peritoneal cavity induced by carrageenan. However, no effect was observed in the dextran-induced paw edema and abdominal contortions induced by acetic acid. Moreover, albumins (20mg/kg) significantly reduced the second (inflammatory) phase of the licking time induced by formalin. The detection of heammaglutinating activity against human erythrocytes in albumins evidences the presence of lectin in seeds of C. retusa. Our data showed that seeds of C. retusa had anti-inflammatory and antinociceptive properties and such activities are probably due to the inhibitory effect on neutrophil migration of lectin present in albumins.

Physio-pharmacological Investigations About the Anti-inflammatory and Antinociceptive Efficacy of (+)-Limonene Epoxide.

D-limonene epoxidation generates (+)-limonene epoxide, an understudied compound in the pharmacologically point of view. Herein, we investigated the anti-inflammatory and antinociceptive potentialities of (+)-limonene epoxide and suggested a mechanism of action. The anti-inflammatory potential was analyzed using agents to induce paw edema, permeability, and myeloperoxidase (MPO) activity. Pro-inflammatory cytokines and cell migration of peritoneal cells were also assessed. Antinociceptive effects were evaluated by writhing test induced by acetic acid, formalin, and hot plate assays and contribution of opioid pathways. Pretreated animals with (+)-limonene epoxide showed reduced carrageenan-induced paw edema in all doses (25, 50, and 75 mg/kg) (P < 0.05). At 75 mg/kg, it suppressed edema provoked by compound 48/80, histamine, prostaglandin E2, and serotonin and reduced permeability determined by Evans blue and MPO activity. It also reduced leukocytes, neutrophils, and IL-1ß levels in the peritoneal cavity in comparison with carrageenan group (P < 0.05). (+)-Limonene epoxide diminished abdominal contortions induced by acetic acid (78.9%) and paw licking times in both 1 (41.8%) and 2 (51.5%) phases and a pretreatment with naloxone (3 mg/kg) reverted the antinociceptive action in morphine- and (+)-limonene epoxide-treated groups (P < 0.05). Additionally, it enlarged response times to the thermal stimulus after 60 and 90 min. In conclusion, (+)-limonene epoxide inhibited release/activity of inflammatory mediators, vascular permeability, migration of neutrophils and displayed systemic and peripheral analgesic-dependent effects of the opioid system.

Riparin B, a Synthetic Compound Analogue of Riparin, Inhibits the Systemic Inflammatory Response and Oxidative Stress in Mice.

The aim of our study was to evaluate the anti-inflammatory, anti-nociceptive, and anti-oxidant action of Riparin B in vivo. We performed experiments in which we induced paw edema by carrageenan and other mediators, carrageenan-induced peritonitis and the level of myeloperoxidase (MPO) activity, pro-inflammatory cytokines (TNF-α and IL-1ß), malondialdehyde (MDA) acid, and glutathione (GSH) from the peritoneal fluid. We also performed behavior tests such as acetic acid-induced writhing, formalin-induced linking, and the hot plate test. Among the doses tested of the Riparin B (1, 3, and 10 mg/kg), the dose of 10 mg/kg showed the strongest effect, and this dose was able to reduce the paw edema induced by carrageenan, dextran, histamine serotonin, bradykinin, 48/80, and PGE2. Similarly, the Riparin B in the same dose reduced cell migration and significantly decreased the nociception induced by formalin and acetic acid and reversed the parameters of the oxidative stress. Thus, we can infer that Riparin B exhibits anti-inflammatory, anti-nociceptive, and anti-oxidant actions in vivo.

Gabapentin, a synthetic analogue of gamma aminobutyric acid, reverses systemic acute inflammation and oxidative stress in mice.

The aim of this study was to investigate the potential anti-inflammatory and anti-oxidant effects of gabapentin (GBP) in mice. The anti-inflammatory and anti-oxidant effects were evaluated using various mediators that induce paw edema, peritonitis model, myeloperoxidase (MPO) activity, proinflammatory cytokine levels, glutathione (GSH) consumption, and malondialdehyde (MDA) production in mice. Pretreatment of mice with GBP (1 mg/kg) significantly reduced carrageenan or dextran-induced paw edema (P<0.05) when compared to vehicle group. Adding to this, GBP (1 mg/kg) significantly inhibited paw edema induced by histamine, serotonin, bradikinin, 48/80 compound, and prostaglandin E2. In the carrageenan-induced peritonitis model, GBP significantly decreased total and differential leukocyte counts and reduced the levels of MPO activity in the plantar tissue and IL-1ß and TNF-α concentrations in the peritoneal exudate. The same dose of GBP also decreased the MDA concentration and increased the levels of GSH into the peritoneal fluid. In summary, our results demonstrated that GBP exhibited anti-inflammatory activity in mice by reducing the action of inflammatory mediators, neutrophil migration and proinflammatory cytokine levels, and anti-oxidant properties by decreasing the concentration of MDA and increasing the GSH content. These observations raise the possibility that GBP could be used to improve tissue resistance to damage during inflammatory conditions.

Anti-inflammatory effect of a sulphated polysaccharide fraction extracted from the red algae Hypnea musciformis via the suppression of neutrophil migration by the nitric oxide signalling pathway.

OBJECTIVES: The aim of this study was to evaluate the anti-inflammatory effect of a sulphated polysaccharide fraction (PLS) extracted from the alga Hypnea musciformis and investigate the possible involvement of the nitric oxide (NO) pathway in this effect. METHODS: The anti-inflammatory activity of PLS was evaluated using inflammatory agents (carrageenan and dextran) to induce paw oedema and peritonitis in Swiss mice. Samples of paw tissue and peritoneal fluid were removed to determine myeloperoxidase (MPO) activity, NO3 /NO2 levels, and interleukin-1ß (IL-1ß) level. The involvement of NO in the modulation of neutrophil migration in carrageenan-induced paw oedema or peritonitis was also investigated. KEY FINDINGS: Compared with vehicle-treated mice, mice pretreated with PLS (10 mg/kg) inhibited carrageenan-induced and dextran-induced oedema; it also inhibited total and differential peritoneal leucocyte counts in a model of peritonitis. These PLS effects were reversed by l-arginine treatment and recovered with the administration of a NO synthase blocker (aminoguanidine). Furthermore, PLS reduced the MPO activity, decreased IL-1ß levels, and increased NO3 /NO2 levels in the peritoneal cavity. CONCLUSIONS: PLS reduced the inflammatory response by modulating neutrophil migration, which appeared to be dependent on the NO pathway.