An investigation of the anti-inflammatory and analgesic effects of Orthosiphon stamineus leaf extract

Anti-inflammatory and analgesic activities of a standardized Orthosiphon stamineus methanol:water (50:50 vol/vol) leaf extract (SEOS) were evaluated in animal models. Oral administration of SEOS at doses of 500 and 1,000 mg/kg significantly reduced the hind paw edema in rats at 3 and 5 hours after carrageenan administration (P < .01 and P < .01; P < .01 and P < .05, respectively). SEOS (1,000 mg/kg, p.o.) also produced significant (P < .05) analgesic activity in both the acetic acid-induced writhing test and the formalin-induced licking test (late phase) in mice and rats, respectively. However, SEOS showed no effect on the tail flick and hot plate tests in mice. The results of the present study support the proposal that O. stamineus has anti-inflammatory and non-narcotic analgesic activities. These findings justify the traditional use of the plant for treating pain and inflammation.     

Eicosapentaenoic acid and docosahexaenoic acid exert anti-inflammatory and antinociceptive effects in rodents at low doses

In the present study, we evaluated omega-3 polyunsaturated fatty acid (PUFA) (consisting of 20:5n-3 and 22:6n-3) properties on inflammation and nociception. Among the in vivo tests, writhing, formalin, and hot plate tests were conducted in mice, and carrageenan-induced paw edema, peritonitis, and Hargreaves tests were performed in rats. Following the carrageenan-induced edema, immunohistochemistry for tumor necrosis factor-α (TNF-α) was also carried out. We found that omega-3 PUFA treatment significantly decreased acetic acid–induced abdominal contortions as well as the first and second phases of the formalin test, which were reversed by naloxone. The carrageenan-induced rat paw edema was significantly reduced, along with neutrophil migration to the peritoneal cavity in the omega-3 PUFA treatment. In addition, there was a decrease in TNF-α immunostained cells in the inflamed paw with the omega-3 treatment compared with no omega-3. Withdrawal threshold in response to the thermal stimulation was significantly increased by the omega-3 treatment in the Hargreaves and hot plate tests. The in vitro studies (myeloperoxidase, lactate dehydrogenase, MTT cell viability and lipid peroxidation assays) were performed in human neutrophils. These studies showed that omega-3 treatment significantly decreased myeloperoxidase release, presented no cytotoxicity, and did not alter lipid peroxidation. Our study suggests that omega-3 PUFA anti-inflammatory and antinociceptive actions may involve inhibition of cyclooxygenases and microglial activation, leading to a reduced release of proinflammatory cytokines such as TNF-α, among other factors. The omega-3 PUFAs are potential candidates used alone or in combination with conventional nonsteroidal anti-inflammatory drugs, for the treatment of diseases where inflammation plays an important role.     

Chrysophyllum albidum fruit peel attenuates nociceptive pain and inflammatory response in rodents by inhibition of pro-inflammatory cytokines and COX-2 expression through suppression of NF-κB activation

Chrysophyllum abidum fruit is a seasonal fruit commonly eaten as snacks with abundant health promoting phytochemicals in the fruit peels. The fruit peels have been reported to be rich in anti-inflammatory eleagnine, myricetin rhamnoside, quercetin, linoleic acid and oleic acid. We hypothesized that the anti-inflammatory effect of the peel extract involve suppression of pro-inflammatory cytokines, cyclooxygenase-2 and nuclear factor-kappa B (NF-κB). Hence, this study was designed to assess the anti-nociceptive and anti-inflammatory effects of fruit peel extract of Chrysophyllum albidum in animal models of nociception and inflammation. The anti-nociceptive activity of CAPEE (100 and 400 mg/kg) was evaluated in acetic acid-induced writhing and formalin-induced paw licking in mice. Formalin-induced paw edema and carrageenan-induced air pouch models of inflammation were used to evaluate the anti-inflammatory activity. CAPEE (100 and 400 mg/kg) significantly reduced abdominal writhing and paw licking in acetic acid and formalin tests in mice, respectively. CAPEE demonstrated significant inhibition of paw edema at 24 h (41.0% and 55.7%) and 72 h (52.3% and 86.6%) after formalin injection. CAPEE suppressed inflammatory responses in carrageenan-induced air pouch by reducing exudates, inflammatory cells infiltration, nitrites and myeloperoxidase activity. There was significant inhibition of tumor necrosis factor-alpha, interleukin-6 levels and reduced immunopositive expression of COX-2 and NF-κB. In conclusion, CAPEE has anti-nociceptive and anti-inflammatory potentials via mechanisms associated with inhibition of pro-inflammatory cytokines and cyclooxygenase-2 (COX-2) expression through suppression of nuclear factor kappa B (NF-κB) activation, and has potential as a functional food ingredient.     

Antioxidant, antinociceptive, and anti-inflammatory properties of the ethanolic extract of Combretum duarteanum in rodents

The antioxidant, antinociceptive, and anti-inflammatory activities of the ethanolic extract from leaves of Combretum duarteanum (EEC) were assessed in rodents through in vitro tests. The antioxidant activity was investigated by using thiobarbituric acid reactive species (TBARS), hydroxyl radical-scavenging, and scavenging activity of nitric oxide assays. The antinociceptive activity was investigated by using acetic acid-induced writhing, formalin, and hot-plate tests in mice. The anti-inflammatory activity was assessed in rats by using the carrageenan-induced hind-paw edema test and arachidonic acid-induced paw edema test. EEC possesses a strong antioxidant potential according to the TBARS, nitric oxide, and hydroxyl radical-scavenging assays; it also presented scavenger activity in all in vitro tests. After intraperitoneal injection, EEC (100, 200, and 400 mg/kg) significantly reduced the number of writhes (38.1%, 90.6%, and 97.8%, respectively) in a writhing test and the number of paw licks during phase 1 (30.5% and 69.5%, higher doses) and phase 2 (38.1%, 90.6%, and 97.8%, all doses) of a formalin test when compared with the control group. Naloxone (1.5 mg/kg, intraperitoneally) antagonized the antinociceptive action of EEC (400 mg/kg), and this finding suggests participation of the opioid system. Administration of 200 and 400 mg/kg (intraperitoneally) of EEC exhibited an anti-inflammatory activity in the carrageenin test, which was based on interference with prostaglandin synthesis. This finding was confirmed by the arachidonic acid test. Together, these results indicate that properties of EEC might be further explored in the search for newer tools to treat painful inflammatory conditions, including those related to pro-oxidant states.     

Evaluation of soybean methanol fraction on acute inflammation

Soybeans have been of interest of researchers because of the presence of isoflavones, a subclass of flavonoids, which have demonstrated anti-inflammatory activity. The aim of this study was investigate the anti-inflammatory activity of the methanol fraction from soybean, which contains mainly isoflavone glucosides and malonylglucosides. The anti-inflammatory activity of the methanol fraction from soybean was studied using croton oil-induced mouse ear edema and carrageenan-induced pleurisy models. The methanol fraction inhibited the ear edema in a dose-dependent manner: 0.625 mg/kg by 44.23% (P<.05), 1.25 mg/kg by 60.68% (P<.01), and 2.5 mg/kg by 65.68% (P<.01). Myeloperoxidase enzyme activity was reduced at the dose of 2.5 mg/kg (64.79%, P<.05). No effects were seen on carrageenan-induced pleurisy at different doses of the methanol fraction (100 or 400 mg/kg). These results demonstrated that the methanol fraction containing conjugated isoflavones showed topical anti-inflammatory activity. There was no acute toxicity in Swiss mice after oral administration of the fraction, at doses of 1,000, 2,000, 3,000, and 4,000 mg/kg.     

Design and microwave-assisted synthesis of 5-trifluoromethyl-4,5-dihydro-1H-pyrazoles: novel agents with analgesic and anti-inflammatory properties

In this work, we reported the synthesis and evaluation of the analgesic and anti-inflammatory properties of novel 3- or 4-substituted 5-trifluoromethyl-5-hydroxy-4,5-dihydro-1H-1-carboxyamidepyrazoles (where 3-/4-substituent=H/H, Me/H, Et/H, Pr/H, i-Pr/H, Bu/H, t-Bu/H, Ph/H, 4-Br-Ph/H and H/Me) designed in the exploration of the bioisosteric replacement of benzene present in salicylamide with a 5-trifluoromethyl-4,5-dihydro-1H-pyrazole scaffold. Target compounds were synthesized from the cyclocondensation of 4-alkoxy-1,1,1-trifluoromethyl-3-alken-2-ones with semicarbazide hydrochloride through a rapid one-pot reaction via microwave irradiation. In addition to spectroscopic data, the structure of the compounds was supported by X-ray diffraction. Subcutaneous administration of the 5-trifluoromethyl-4,5-dihydro-1H-pyrazoles decreased pain-related behavior during neurogenic and inflammatory phases of the formalin test in mice. Moreover, the more active analgesic compounds (3-/4-=Et/H and H/Me) significantly decreased carrageenan-induced paw edema in mice. The data obtained in this work suggest that the synthesized compounds could be promising candidates for the future development of novel analgesic and anti-inflammatory agents.     

Synthesis and pharmacological evaluation of a novel series of 5-(substituted)aryl-3-(3-coumarinyl)-1-phenyl-2-pyrazolines as novel anti-inflammatory and analgesic agents

A novel series of 5-(substituted)aryl-3-(3-coumarinyl)-1-phenyl-2-pyrazolines (3a-l) were synthesized by reacting various substituted 3-aryl-1-(3-coumarinyl)propan-1-ones (2a-l) with phenylhydrazine in the presence of hot pyridine. Structures of all new synthesized compounds were characterized on the basis of elemental analysis and spectral data (IR, (1)H NMR and (13)C NMR). The title compounds were screened for in vivo anti-inflammatory and analgesic activities at a dose of 200 mg/kg b.w. Among the 12 prepared compounds, Compounds 3d, e, i and j exhibited significant anti-inflammatory activity in model of acute inflammation such as carrageenan-induced rat edema paw while compounds 3d and e showed considerable activity in model of chronic inflammation such as adjuvant-induced arthritis and were compared with diclofenac (13.5 mg/kg b.w.) as a standard drug. These compounds were also found to have significant analgesic activity in the acetic acid induced writhing model and antipyretic activity in yeast-induced pyrexia model along with minimum ulcerogenic index.     

Novel β-carboline-tripeptide conjugates attenuate mesenteric ischemia/reperfusion injury in the rat

We have synthesized a series of new β-carboline-tripeptide conjugates, and examined their anti-inflammatory properties in a mouse model of xylene-induced ear edema. The analgesic capacity of these compounds was further evaluated in a rodent tail flick assay. Our results indicate that β-carboline conjugate 4a manifests potent anti-inflammatory and analgesic activity while exerting a protective effect against mesenteric ischemia/reperfusion (I/R) injury in the rat.     

Synthesis, analgesic and anti-inflammatory activities of novel 3-(4-acetamido-benzyl)-5-substituted-1,2,4-oxadiazoles

A series of 3-(4-acetamido-benzyl)-5-substituted-1,2,4-oxadiazoles (7a-7n) were synthesized and screened for analgesic and in vivo anti-inflammatory activities using acetic acid writhing in mice model and carrageenan-induced paw oedema method in mice, respectively. The analgesic activity of compounds 7i and 7m is superior while that of 7d, 7c, 7f and 7j is equal to the reference standard, diclofenac sodium. The anti-inflammatory activity of compounds 6, 7c, 7e, 7f, 7i, 7l, 7m and 7n is found to be superior than that of diclofenac sodium which is used as a reference, while compounds 7d and 7g are found to be equipotent with the reference compound.     

Anti-inflammatory effects of anthocyanins-rich extract from bilberry (Vaccinium myrtillus L.) on croton oil-induced ear edema and Propionibacterium acnes plus LPS-induced liver damage in mice

Bilberry (Vaccinium myrtillus L.) has been known to play a protective role in human health due to its high anthocyanin content. This study investigated the anti-inflammatory effects of bilberry extract (BE, containing 42.04% anthocyanin) on Propionibacterium acnes (P. acnes) plus lipopolysaccharide (LPS) induced liver injury and croton oil-induced ear edema in mice. Results showed that BE could effectively inhibit croton oil-induced ear edema and liver inflammation provoked by P. acnes plus LPS, as reflected by the reduced plasma alanine aminotransferase and aspartate aminotransferase activities. These findings were confirmed by hepatic pathological examination. Moreover, BE administration markedly suppressed the increase of liver mRNA levels of iNOS, TNF-α, IL-1β and IL-6, and the protein levels of iNOS, TNF-α and NF-κB. In addition, liver malondialdehyde and NO contents were significantly reduced by BE treatment. These results indicated that BE has potent protective effects on acute and immunological inflammation, which might contribute to the study of the anti-inflammatory effects of natural products and healthy food.     

In Vivo Analgesic and Antipyretic Activities of N-Butanol and Water Fractions of Ocimum Suave Aqueous Leaves Extract in Mice

Background

Ocimum suave willd is one of the plants traditionally used for the treatment of inflammation and related disorders in different parts of Ethiopia. The aim of the current study was to evaluate the analgesic and antipyretic activities of the solvent fractions (n-butanol and water) of O. suave aqueous leaves extract.

Materials and Methods

Acetic acid writhing and tail flick tests were used to evaluate the analgesic activity, and yeast-induced fever in mice was used to evaluate the antipyretic activity of the solvent fractions.

Results

Both solvent fractions exhibited inhibitory effect against acetic acid induced writhing at all tested dose levels in a dose dependent manner. The water fraction inhibited writhing by 47.69% at a dose of 200 mg/kg which was comparable to that by ASA, the standard drug. In the tail flick test, 200 mg/kg dose of both solvent fractions showed significant activity (P<0.05) after 0.5h, 1h and 3hrs of their administration. Both n- butanol and water fractions produced significant reduction in yeast induced fever at all doses employed.

Conclusion

From these findings, it can be concluded that the n-butanol and water fractions of O. suave aqueous leaves extract have potential analgesic and antipyretic activity in mice.     

Anti-inflammatory effects of the chloroform extract of Pulicaria guestii ameliorated the neutrophil infiltration and nitric oxide generation in rats

Pulicaria guestii Rech.f. & Rawi is a fragrant, perennial herb, which grows wild, west of Al-Madinah, Saudi Arabia. Several reports were published on the anti-inflammatory activity of the sesquiterpene lactones, phenolics and flavonoids, which constitute the main active constituents of the members of the genus Pulicaria. The present study was designed to explore the potential anti-inflammatory effect of P. guestii in several experimental models. The methanol extract of the dried aerial parts of P. guestii was extracted with petroleum ether, chloroform and n-butanol. The chloroform extract was analysed on TLC and examined under UV and visible light in presence of AlCl(3) spray. The free radical scavenging activity and the total phenolic content in the CHCl(3) extract were estimated. The crude methanol extract and the CHCl(3) fraction were examined against carrageenin-induced paw edema and ear edema induced by croton oil application. The crude methanolic extract significantly reduced carrageenin-induced rat paw edema. After fractionation, the chloroform fraction caused significant reduction in carrageenin-induced rat paw edema in addition to diminishing prostaglandin E(2) (PGE(2)) in the inflammatory exudates. Topical application of chloroform fraction significantly reduced rat ear edema induced by croton oil application. In the same model, chloroform fraction reduced neutrophil infiltration, as indicated by the significant decrease in myeloperoxidase activity, and ameliorated histopathological changes induced by croton oil application. In lipopolysaccharide-induced inflammation in rat air pouch, chloroform fraction significantly reduced the nitric oxide level and tumor necrosis factor-α release. In conclusion, the chloroform fraction of P. guestii extract possesses anti-inflammatory activity in several experimental models. Further investigations are needed to identify the active constituents responsible for this anti-inflammatory activity.     

Synthesis and biological evaluation of amide derivatives of (5,6-dimethoxy-2,3-dihydro-1H-inden-1-yl)acetic acid as anti-inflammatory agents with reduced gastrointestinal ulcerogenecity

A variety of amide derivatives of (5,6-dimethoxy-2,3-dihydro-1H-inden-1-yl)acetic acid were synthesized and screened for their analgesic and anti-inflammatory activities. The compounds were found to have longer activity profile exceeding that of indomethacin in carrageenan-induced rat paw edema model. Few selected compounds were also screened for their antipyretic, anti-arthritic and ulcerogenecity potential. From these studies it can be concluded that these compounds though have significant antipyretic activity did not act through the inhibition of TNF-alpha. The test compounds failed to prevent the development of secondary inflammation in adjuvant-induced arthritis assay. However, these compounds showed no ulcer formation at the tested dose level of 100 mg/kg p.o.     

Aroylpropionic acid based 2,5-disubstituted-1,3,4-oxadiazoles: synthesis and their anti-inflammatory and analgesic activities

Synthesis and biological evaluation of various aroylpropionic acid derivatives containing 1,3,4-Oxadiazole nucleus is reported here. The compounds (3a-w) were synthesized by cyclization of 3-aroylpropionic acids into 1,3,4-oxadiazole nucleus by treating with various aryl acid hydrazides in the presence of POCl(3). The structures of new compounds are supported by IR, (1)H NMR and MS data. These compounds were tested in vivo for their anti-inflammatory activity. All the compounds tested showed anti-inflammatory activity. The compounds which showed activity comparable to the standard drug ibuprofen were screened for their analgesic, ulcerogenic and lipid peroxidation activities. Seven (3c, g, i, j, m, o, p) out of 23 new compounds showed very good anti-inflammatory activity in the carrageenan-induced rat paw edema test with very less ulcerogenic action. The compounds, which showed less ulcerogenic action, also showed reduced malondialdehyde production (MDA), which is one of the byproducts of lipid peroxidation. Compound 3i and o showed 89.50 and 88.88% of inhibition in paw edema, 69.80 and 66.25% protection against acetic acid induced writhings and 0.7 and 0.65 of severity index respectively, compared to 90.12, 72.50 and 1.95 values of ibuprofen. The study showed that the cyclization of carboxylic group of aroylpropionic acids into an oxadiazole nucleus resulted in compounds having good anti-inflammatory and analgesic effects with reduced gastric irritation.     

New analgesic and antiinflammatory agents 4(1H)-pyridinone derivatives

A series of 1,2,5-trisubstituted 4(1H)-pyridinone derivatives (7-14) were synthesised by using 4-pyrone derivatives with primary amines in ethanol. The structures of the synthesised compounds were confirmed by analytical and spectral data (UV, IR and 1H-NMR and microanalysis). Analgesic and antiinflammatory activities of the synthesised compounds were investigated by acetic acid-induced writhing syndrome and carrageenan rat paw edema tests. All of the test compounds exhibited higher analgesic activities than acetyl salicylic acid and showed higher antiinflammatory activities than indomethacin. The anti-inflammatory activity and gastric ulceration potential of the compounds were tested using indomethacin as reference drug.     

Anti-inflammatory activity of Pistacia khinjuk in different experimental models: isolation and characterization of its flavonoids and galloylated sugars

The present study aimed at isolating and elucidating the structure of the main components of Pistacia khinjuk L. and exploring its potential anti-inflammatory effect in different experimental models. The extract was evaluated for anti-inflammatory activity by measuring paw volume in three experimental models. Then, prostaglandin E? (PGE?) level, ear edema, tissue myeloperoxidase (MPO) activity, histopathology, nitric oxide (NO) level, and tumor necrosis factor-α (TNF-α) level were assessed. Seven phenolic compounds, mainly flavonoids and galloylated compounds, were isolated from the aqueous methanol extract: gallic acid (1), methyl gallate (2), quercetin-3-O-β-D-?C?-galactopyranoside (hyperin) (3), myricetin-3-O-α-L-1C?-rhamnopyranoside (myricitrin) (4), 1,6-digalloyl-β-D-glucose (5), 1,4-digalloyl-β-D-glucopyranoside (6), and 2,3-di-O-galloyl-(α/β)-?C?-glucopyranose (nilocitin) (7). The anti-inflammatory activity was evidenced by decreased carrageenan-induced rat paw edema and PGE? elevation. In the croton oil-induced ear edema model, MPO activity was significantly inhibited, and inflammatory histopathological changes were ameliorated. In the rat air pouch model, NO generation and TNF-α release were significantly inhibited. The isolation and nuclear magnetic resonance spectral data of compound 6 from the genus Pistacia are revealed for the first time. Also, P. khinjuk L. aqueous methanol extract possesses anti-inflammatory activity in several experimental models.     

Synthesis and anti-inflammatory, analgesic, ulcerogenic and lipid peroxidation activities of some new 2-[(2,6-dichloroanilino) phenyl]acetic acid derivatives

The synthesis of a group of 1,3,4-oxadiazoles, 1,2,4-triazoles, 1,3,4-thiadiazoles and 1,2,4-triazine derived from 2-[(2,6-dichloroanilino) phenyl] acetic acid is described. The structures of new compounds are supported by IR, (1)H-NMR and Mass spectral data. These compounds were tested in vivo for their anti-inflammatory activity. The compounds, which showed activity comparable to the standard drug diclofenac, were screened for their analgesic, ulcerogenic and lipid peroxidation activities. Ten new compounds, out of 28 showed very good anti-inflammatory activity in the carrageenin induced rat paw edema test, with significant analgesic activity in the acetic acid induced writhing test together with negligible ulcerogenic action. The compounds, which showed less ulcerogenic action, also showed reduced malondialdehyde content (MDA), which is one of the byproduct of lipid peroxidation. The study showed that the compounds inhibited the induction of gastric mucosal lesions and it can be suggested from our results that their protective effects may be related to inhibition of lipid peroxidation in the gastric mucosa.     

Research on heterocyclic compounds, XLI. 2-Phenylimidazo

The synthesis of a group of 2-phenylimidazo[1,2-b]pyridazine-3-acetic esters and acids is described. The structures of the new compounds are supported by 1H-NMR spectra. These compounds were tested in vivo for their anti-inflammatory, analgesic and ulcerogenic activity. All new compounds showed remarkable anti-inflammatory action in the carrageenan rat paw oedema (one third of that for indomethacin) but no significant analgesic activity in the acetic acid writhing test together with negligible ulcerogenic action, and were also found to be lacking inhibitory activity on cyclooxygenase in vitro.     

1,3,4-Oxadiazole/thiadiazole and 1,2,4-triazole derivatives of biphenyl-4-yloxy acetic acid: synthesis and preliminary evaluation of biological properties

A series of 1,3,4-oxadiazole/thiadiazole and 1,2,4-triazole derivatives of biphenyl-4-yloxy acetic acid were synthesized in order to obtain new compounds with potential anti-inflammatory activity, analgesic activity and lower ulcerogenic potential. All compounds were evaluated for their anti-inflammatory activity by the carrageenan induced rat paw edema test method. The compounds possessing potent anti-inflammatory activity were further tested for their analgesic, ulcerogenic and antioxidant activities. Out of all tested compounds, the compounds 3, 7, 17 and 20, showed significant reduction in rat paw edema induced by carrageenan treatment. These compounds showed significant analgesic effect and at an equimolar oral doses relative to flurbiprofen were also found to be non-gastrotoxic in rats. Compound 17 was evaluated as the lead compound having more anti-inflammatory activity (81.81%) than the reference drug (79.54%), low ulcerogenic potential and protective effect on lipid peroxidation.     

Anti-inflammatory effects of seeds of the tropical fruit camu-camu (Myrciaria dubia)

The methanolic extract of seeds of the tropical fruit camu-camu was screened for its anti-inflammatory activity in carrageenan-induced paw edema model mice. The extract significantly suppressed both the formation of edema in mice by oral administration and the release of nitric oxide from macrophage-derived RAW 264.7 cells in vitro. Based on the results of a spectroscopic analysis, the active compound was identified by in vivo bioassay-guided fractionation to be 3β-hydroxy-lup-20(29)-en-28-oic acid, betulinic acid, known as an anti-inflammatory triterpenoid. These findings suggest that camu-camu seed extract is a potentially useful material as a source of betulinic acid and as a functional food for prevention of immune-related diseases.