Formalin-induced Paw Licking Test Research Articles

In vivo and in vitro pharmacological activities\xa0of Tacca integrifolia rhizome and\xa0investigation of possible lead compounds against breast cancer through in silico approaches

BackgroundThe study was conducted to evaluate the analgesic, anti-inflammatory, antipyretic properties of ethanolic extract of Tacca integrifolia rhizome (EETI) in mice and cytotoxic effects in brine shrimp nauplii followed by a PASS prediction study for some isolated compounds of T. integrifolia. Additionally, this experiment included the in silico molecular docking and ADME/T property analyses of some phytochemicals.MethodsFormalin- induced paw licking test and acetic acid-induced writhing test for analgesic activity, carrageenan-induced paw edema test for anti-inflammatory potential and Brewer’s yeast-induced pyrexia test for antipyretic activity were applied. Antinociceptive and antineoplastic activity for breast cancer were revealed with PASS program. Schrodinger suite 2015 was used to evaluate the binding interaction and ADME/T properties of selected phytoconstituents with estrogen receptor alpha.ResultsIn formalin-induced paw licking test, EETI at the doses of 200 and 400 mg/kg BW showed highly significant inhibition of writhing in both neurogenic and inflammatory phases. While EETI also exhibited highly significant, compared to control, writhing inhibition for both the doses in acetic acid-induced writhing test. Moderate anti-inflammatory effect at a dose of 400 mg/kg BW was noticed in paw-edema test. It also showed 77.51% of maximum antipyretic effect which was significantly effective compared to standard drug paracetamol (150 mg/kg) in Brewer’s yeast-induced pyrexia test. The EETI showed potential cytotoxic activity with LC50 value of 114.46 μg/mL. The PASS prediction revealed the potential antinociceptive and antineoplastic activity of target compounds. The compounds betulinic acid, quercetin-3-α-arabinoside, catsanogenin were found to be effective in molecular docking study.ConclusionIt is evident that the EETI possesses highly significant analgesic activity with remarkable anti-inflammatory and antipyretic activity. The phytoconstituents have potential antinociceptive and antineoplastic (breast cancer) activity.Graphical abstract

Ficus cunia Buch.-Ham. ex Roxb. (leaves): An experimental evaluation of the cytotoxicity, thrombolytic, analgesic and neuropharmacological activities of its methanol extract.

Background The aim of this experiment was to evaluate the cytotoxic, thrombolytic, analgesic, sedative-hypnotic and anxiolytic activities of the methanolic extract of Ficus cunia leaves. Methods Primary phytochemical screening was accomplished by using established methods. Cytotoxicity was studied by brine shrimp lethality test, and the thrombolytic assay was conducted through clot lysis method with human blood. The in vivo action was done using mice of both sexes. The analgesic activity was evaluated by acetic acid-induced writhing test and formalin-induced paw licking test. Open field, hole cross and thiopental Na-induced sleeping time test were used to examine the sedative-hypnotic activity, and elevated plus maze (EPM) and hole board test were used to identify the anxiolytic activity. Results The results elicited that the extract contained several phytochemicals such as alkaloid, flavonoid, and tannin. The extract was found to have a median lethal concentration (LC50) value of 55.48 μg/mL in the brine shrimp lethality bioassay. It was also assessed for antithrombotic activity when compared with streptokinase; it has significant (p < 0.001) thrombolytic effect (34.72 ± 1.74%) contrasted with standard streptokinase (67 ± 1.56%). The extract at doses of 200 and 400 mg/kg produced inhibition of 32.58% and 46.63% in acetic acid-induced pain and 45.88 and 61.18% in formalin-induced pain. The sedative and hypnotic activities on the central nervous system of the methanol extract of F. cunia (MEFC) leaves were evaluated. The extract delivered critical sedative impact at the doses of 200 and 400 mg/kg (by oral route) treated with reference to the substance diazepam, and the hypnotic impact was also observed in the case of mice. MEFC at its maximum dose (400 mg/kg) significantly (p < 0.01) increased the time spent in the open arms of the EPM. In the hole board test, there was a dose-dependent (at 200 and 400 mg/kg) and a significant (p < 0.05 and p < 0.01) increase in the number of head pokes in comparison to control. Conclusions The results of the present study gave a helpful baseline in progression for the possible use of MEFC as a cytotoxic, thrombolytic, analgesic, sedative-hypnotic and anxiolytic drug.

Anti-inflammatory, antinociceptive and antidiarrhoeal activities of methanol and ethyl acetate extract of Hemigraphis alternata leaves in mice

BackgroundThe study was designed to investigate the qualitative phytochemical constituents and evaluate the anti-inflammatory, anti-nociceptive and anti-diarrhoeal activities of methanol (MHAL) and ethyl acetate (EAHAL) extract of Hemigraphis alternata leaves in Swiss albino mice.MethodsQualitative phytochemical constituents of MHAL and EAHAL were determined by different tests such as Molisch’s test, Fehling test, Mayer’s test, Frothing test, FeCl3 test, Alkali test, Salkowski’s test, Keller-killiani test and CuSO4 test. In addition, Xylene induced-ear edema test and Cotton pellet-induced granuloma formation test had been performed to evaluate the anti-inflammatory activity. Moreover, Formalin-induced paw licking test, Acetic acid-induced writhing tests and Castor oil induced antidiarrheal test had been performed to evaluate the anti-nociceptive and anti-diarrhoeal activities respectively.ResultsThese crude extracts were figured the presence of carbohydrates, flavonoids, tannins, glycosides, triterpenoids, fat and fixed oils. No mortality, behavioral changes or sign of any toxicity were observed up to the dose as high as 4000 mg/kg in mice. During anti-inflammatory test, MHAL 400 mg/kg and EAHAL 200 mg/kg & 400 mg/kg were significantly reduced ear weight differences and granuloma formation in mice. Highest percentage inhibition was offered by EAHAL 400 mg/kg dose (35.15 ± 11.78% and 34.76 ± 11.30%) in both anti-inflammatory tests respectively. In anti-nociceptive experiments, all extracts were significantly reduced paw licking and abdominal writhing of mice. Highest percentage inhibition was offered by EAHAL 400 mg/kg dose (88.21 ± 2.23% and 54.00 ± 2.38%) in both anti-nociceptive tests respectively. In addition, both extracts were showed significant inhibition of percentage of diarrhea in anti-diarrhoeal models except EAHAL 200 mg/kg dose and the apex percentage inhibition is offered by MHAL 400 mg/kg dose (67.73 ± 5.77%).ConclusionThese results confirm that the leaves extract of Hemigraphis alternata are nontoxic and may provide a source of plant compounds with anti-inflammatory, anti-nociceptive and anti-diarrhoeal activities.

Antinociceptive activity of petroleum ether fraction obtained from methanolic extract of Clinacanthus nutans leaves involves the activation of opioid receptors and NO-mediated/cGMP-independent pathway

BackgroundMethanol extract (MECN) of Clinacanthus nutans Lindau leaves (family Acanthaceae) demonstrated peripherally and centrally mediated antinociceptive activity via the modulation of opioid/NO-mediated, but cGMP-independent pathway. In the present study, MECN was sequentially partitioned to obtain petroleum ether extract of C. nutans (PECN), which was subjected to antinociceptive study with aims of establishing its antinociceptive potential and determining the role of opioid receptors and l–arginine/nitric oxide/cyclic-guanosine monophosphate (l–arg/NO/cGMP) pathway in the observed antinociceptive activity.MethodsThe antinociceptive potential of orally administered PECN (100, 250, 500 mg/kg) was studied using the abdominal constriction-, hot plate- and formalin-induced paw licking-test in mice (n = 6). The effect of PECN on locomotor activity was also evaluated using the rota rod assay. The role of opioid receptors was determined by pre-challenging 500 mg/kg PECN (p.o.) with antagonist of opioid receptor subtypes, namely β–funaltrexamine (β–FNA; 10 mg/kg; a μ-opioid antagonist), naltrindole (NALT; 1 mg/kg; a δ-opioid antagonist) or nor–binaltorphimine (nor–BNI; 1 mg/kg; a κ-opioid antagonist) followed by subjection to the abdominal constriction test. In addition, the role of l–arg/NO/cGMP pathway was determined by prechallenging 500 mg/kg PECN (p.o.) with l–arg (20 mg/kg; a NO precursor), 1H-[1, 2, 4] oxadiazolo [4,3-a]quinoxalin-1-one (ODQ; 2 mg/kg; a specific soluble guanylyl cyclase inhibitor), or the combinations thereof (l–arg + ODQ) for 5 mins before subjection to the abdominal constriction test. PECN was also subjected to phytoconstituents analyses.ResultsPECN significantly (p < 0.05) inhibited nociceptive effect in all models in a dose-dependent manner. The highest dose of PECN (500 mg/kg) also did not significantly (p > 0.05) affect the locomotor activity of treated mice. The antinociceptive activity of PECN was significantly (p < 0.05) inhibited by all antagonists of μ-, δ-, and κ-opioid receptors. In addition, the antinociceptive activity of PECN was significantly (p < 0.05) reversed by l–arg, but insignificantly (p > 0.05) affected by ODQ. HPLC analysis revealed the presence of at least cinnamic acid in PECN.ConclusionPECN exerted antinocicpetive activity at peripheral and central levels possibly via the activation of non-selective opioid receptors and modulation of the NO-mediated/cGMP-independent pathway partly via the synergistic action of phenolic compounds.

Antioxidant Activity, Anti-Inflammatory and Analgesic Effects of Caralluma europaea (Eddaghmouss) in Mice

The aim of the current study is to evaluate the anti-inflammatory, antioxidant and analgesic properties of ethanolic (100 and 200 mg/kg, p.o.) and ethyl acetate extracts (100 and 200 mg/kg, p.o.) of Caralluma europaea. Formalin-induced paw licking test, Acetic Acid induced Writhing Test and Hot-PlateTest were used to assess the analgesic activity. Xylene-induced ear edema test was used to evaluate anti-inflammatory activity of those extracts. In this work, the High-Performance Liquid Chromatography technique (HPLC), allowed us to identify and quantify the main phenolic compounds present in ethanolic and ethyl acetate extracts. In vitro anti-oxidant propriety was evaluated using two methods, the 2,2-Diphenyl-1Picrylhydrazyl (DPPH) radical scavenging method and reducing power methods. The main phenols identified were Catechin (24%) and quercetin (18%) in ethanolic extract, while in the ethyl acetate extract, they were quercetin (36%), P-coumaric (30%) and 2-hydroxycinnamic (25%). Analysis of our results had shown that Caralluma europaea extracts had exhibited a very potent analgesic activity. Percentage of Pain Inhibition (PPI) in the writhing test, 63.60±4.24% for the Ethanolic Extract (EE) (200 mg/kg, p.o.) and 65.39±3.27% for the Ethyl Acetate Extract (EAE). The PPI of early and late phase in the formalin test were respectively, 41% and 73% for EAE (200 mg/kg; p.o), 28% and 75% for EE. In the hotplate test, latency to the thermal stimuli was increased in a dose dependent manner after the administration of EE and EAE. However, the analgesic potential of EAE seems to be higher than EE. Both EE and EAE presented a significant in vitro redox potential and high anti-inflammatory activity. Our results have shown that Caralluma europaea is rich in phenolic compounds and possesses an important antinociceptive, anti-inflammatory and anti-oxidant activity.

&lt;p&gt;Anti-nociceptive and anti-inflammatory activities of crude root extract and solvent fractions of &lt;em&gt;Cucumis ficifolius&lt;/em&gt; in mice model&lt;/p&gt;

Background: Societies in developing countries use traditional medicine as alternatives for management of pain and inflammation. The plant Cucumis ficifolius has been used in Ethiopia to treat many ailments including inflammation and pain. The objective of this study was to evaluate the antinociceptive and anti-inflammatory activities of the crude root extract and solvent fractions of C. ficifolius.Methods: The analgesic activity of crude extract and solvent fractions of C. ficifolius was evaluated with acetic acid-induced writhing, hot plate, and formalin-induced paw licking tests. The anti-inflammatory effect of crude methanolic root extract and solvent fractions of C. ficifolius was evaluated using carrageenan-induced paw edema. The crude extract was given at 200, 400 and 800 mg/kg. Butanol and aqueous fractions were given at 100 and 200 mg/kg doses. The negative control groups were treated with distilled water (10 mL/kg). Standard drugs used were acetylsalicylic acid (ASA) in acetic acid, formalin tests and carrageenan-induced paw edema and morphine (20 mg/kg) in hot plate test.Results: The crude extract, at its maximum dose, produced comparable analgesic activity (72.5%) to ASA in acetic acid writhing test. In the hot plate test, both the crude extract and solvent fractions exhibited a significant prolongation of nociception reaction time. Formalin test result indicated a significant reduction of mean lick time with maximal protection of 64% (early phase) and 83% (late phase). Aqueous and butanol fractions showed good analgesic activity in the three models. Inflammation was decreased by 69% with butanol (200 mg/kg); 71% (800 mg/kg) of crude extract and by 41% and 56% with the use of aqueous fraction at 100 and 200 mg/kg, respectively (p<0.001).Conclusion: The present study indicates that the crude methanolic root extract, as well as butanol and aqueous solvent fractions, showed anti-nociceptive and anti-inflammatory activities.

Phytochemical screening and evaluation of the pharmacological activities of ethanolic extract of Argemone mexicana Linn. aerial parts

The present study was designed to investigate different phytochemical groups present in ethanolic extract of Argemone mexicana aerial parts (EAMA) as well as to assess the analgesic, antidiarrheal, antibacterial, anthelmintic and cytotoxic activities of EAMA. Moreover, peripheral and central analgesic activities were evaluated by acetic acid-induced writhing test, formalin-induced paw licking test, tail immersion test and hot plate test. In vivo castor oil-induced diarrheal model and magnesium sulphate induced diarrheal model in mice were utilized for the assessment of antidiarrheal activity. Again, antibacterial activity was evaluated using disc diffusion assay. Anthelmintic activity was carried out on Paramphistomum cervi (Trematoda). Cytotoxic activity was assessed through brine shrimp lethality bioassay. The extract demonstrated the presence of alkaloids, flavonoids, phenolic compounds, tannins, glycosides and gums in phytochemical screening. In case of acetic acid-induced writhing and formalin induced paw licking test, both lower and higher doses of EAMA showed significant percentage inhibition of writhing as well as paw licking respectively (*P < 0.05, vs. control). EAMA at the doses of 200 mg/kg and 400 mg/kg revealed significant latency response (*P < 0.05, vs. control) in delayed phase in both tail immersion as well as hot plate test. Moreover, significant percentage inhibition (*P < 0.05, vs. control) of diarrhea was exposed by both doses of EAMA in in vivo diarrheal models. In disc diffusion assay, EAMA showed antibacterial activities against both gram positive and gram negative bacterial strains. Again, the extract exhibited anthelmintic and cytotoxic activity in a dose dependent manner.

Assessment of anti-nociceptive and anthelmintic activities of Vitex Peduncularis Wall. leaves and in silico molecular docking, ADME/T, and PASS prediction studies of its isolated compounds

Background: Vitex peduncularis (Verbenaceae), popularly known as ‘Boruna’, ‘Goda’, ‘Ashmul gaas’ (Chakma), ‘Korobaong’ (Marma), is frequently used in the traditional medicine for the treatment of chest pain, joint ache, malarial fevers, diabetes, jaundice, urethritis, and abnormality in eyes and face. Objective: To validate the traditional use, this study was designed to investigate the anti-nociceptive (in vivo) and anthelmintic (in vitro) activity of ethanol extract of V. peduncularis leaves (EEVP). Moreover, computational studies viz. in silico molecular docking, ADME/T, and PASS predictions study were performed to ascertain the association of isolated compounds for the anti-nociceptive and anthelmintic activity as well as their good oral bioavailability and safety traits. Methods: Quantitative phytochemical study of EEVP was carried out by established methods. The anti-nociceptive activity was determined using acetic acid induced writhing and formalin induced paw licking test in mice at the doses of 200 and 400 mg/kg, body weight, whereas an aquarium worm, Tubifex tubifex was used to determine the anthelmintic activity. In silico Molecular docking study was performed using Schrodinger Maestro 10.1 whereas the SwissADME, admetSAR, and PASS online tools were used for ADME, toxicological property, and biological activity predictions respectively. Results: Our quantitative phytochemical study of EEVP revealed the occurrence of a substantial amount of phenolics (121.67 mg), flavonoids (97.78 mg), flavonols (39.88 mg), and condensed tannins (63.49 mg). EEVP exhibited significant and dose-dependent anti-nociceptive activity in both experimental pain models. Besides, EEVP has manifested strong anthelmintic property compared to reference standard drug levamisole. Molecular docking study showed that 3,4-dihydroxybenzoic acid, 4-hydroxybenzoic acid, vitexin, corosolic acid, vitexilactone, and tormentic acid have the best binding affinities towards the respective enzymes (COX-1, COX-2, and tubulin). PASS study also predicted the anti-nociceptive and anthelmintic activity of all isolated compounds. Additionally, ADME/T study exhibited that all the compounds are safe and orally bioavailable from the druggable point of view. Conclusion: The outcomes of our scientific investigation (in vivo, in vitro, and computational studies) significantly support the ethno-medicinal use of this plant, which might be a utilized as an alternative source for the potential drug discovery.

Evaluation of the effectiveness of Acmella uliginosa (Sw.) Cass. flower methanolic extract in pain amelioration and memory impairment in the experimental rat models: Search for an alternative remedy over opioid painkillers

Background: The flower of Acmella uliginosa (AU) (Sw.) Cass., a naturally grown herb in India, is consumed as a natural painkiller for its notable analgesic properties. Objective: The objective of the study was to establish the role of AU flower methanolic extract in antinociception and its neuromodulatory activities to assess any disadvantage of the drug akin to opioids. Materials and Methods: In experimental rats, plant flower extracts were fed at a dose of 100 mg and 200 mg/kg body weight (BW) for 14 days. Analgesic activity was evaluated through formalin-induced paw licking test. T-maze, novel object recognition (NOR), and rotarod tests were done to assess the role of the extract in memory alteration and neuromotor coordination, respectively. Acetylcholinesterase (AChE), reduced glutathione (GSH), and superoxide dismutase (SOD) activity from the brain homogenates were done to assess the induced oxidative stress. Results: The plant proved to be a promising analgesic when fed orally up to 200 mg/kg BW dose. No acute toxicity was seen up to 1000 mg/kg. In the T-maze test, extract-fed animals showed a reduction in food searching time. In NOR test, the discrimination index between new and familiar objects was high in extract-fed animals compared to standard group. In rotarod test, the extract did not alter the neuromotor coordination. AChE, GSH, and SOD activities were normal in extract-treated animals. Conclusion: Memory alteration and oxidative stress are two major drawbacks associated with opioid drugs. Our results indicate that the AU flower methanolic extract qualifies as a potent painkiller and overcomes the disadvantages of opioid analgesics.

Investigation of bioactivities of methanolic and ethyl acetate extracts of Dioscorea pentaphylla leaf along with its phenolic composition

The present study was performed to investigate the in-vitro antioxidant properties, brine shrimp lethality bioassay, and antimicrobial activity and in-vivo analgesic, anti-inflammatory, and antidiarrheal potentiality of methanolic and ethyl acetate extracts of Dioscorea pentaphylla (D. pentaphylla) leaf along with determining the bioactive phenolic compounds by HPLC analysis. Standard methods were used to investigate the aforementioned bioactivities. Methanol extract showed higher total phenolic activity, 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical and Nitric oxide (NO) radical scavenging activities, whereas ethyl acetate extract showed better activities in total flavonoid and total antioxidant capacity assays. Dose-dependent moderate reducing capacity was observed for both extracts in cupric reducing and reducing power capacity assays. The methanol extract was found to be more potent than ethyl acetate extract according to brine shrimp lethality bioactivity test. Both extracts exhibited broad-spectrum antimicrobial activity in the disk diffusion method. In tail immersion test, at 1000 mg/kg dose, both extracts of D. pentaphylla showed a significant (p < 0.05) reduction in pain sensation. Ethyl acetate extract has significantly (p < 0.05) decreased writhing of the tested mice which were induced by acetic acid. The number of licks in formalin-induced paw licking test was markedly (p < 0.05) lessened in both extracts administration. Ethyl acetate extract revealed better anti-inflammatory activities than methanol extract in two well-known anti-inflammatory models (Xylene-induced ear edema, Cotton pellet-induced granuloma formation). Methanol extract displayed potent anti-diarrheal activity. HPLC analysis confirmed the existence of phenolic compounds (gallic acid, rutin, and quercetin) in the leaf extract of D. pentaphylla. These phytochemical constituents might have the role in the observed activities.

In vivo analgesic effect of different extracts of Hopea odorata leaves in mice and in silico molecular docking and ADME/T property analysis of some isolated compounds from this plant.

Background The current study evaluates the analgesic effect of different extracts of Hopea odorata leaves in mice followed by molecular docking and absorption, distribution, metabolism, excretion, and toxicity (ADME/T) analysis of isolated compounds derived from the plant with the COX-1 enzyme. Methods In the present study, the dried leaves of H. odorata were subjected to extraction using methanol, ethanol, and water. In vivo analgesic activity was evaluated by using the acetic acid-induced writhing test and formalin-induced paw licking test, and in silico molecular docking and ADME/T study were performed using Schrödinger Maestro (version 11.1) and online-based tools, respectively, on eight isolated compounds. Results The results showed that the methanolic extract of leaves has highest significant dose-dependent analgesic activity at both 200 and 400 mg/kg followed by ethanolic extract of leaves. Among all the compounds, ampelopsin showed the best docking score of -7.055, ensuring strong binding affinity between the ligand and the receptor, and ADME/T analysis using Web-based tools ensures the compound has not violated Lipinski's rule of five indicating its safety consumption. Conclusions The result confirms the analgesic activity of H. odorata leaves in both in vivo and in silico assays. The data support ampelopsin to be a potent analgesic compound worthy of future clinical trials and its "drug-likeliness".

Pharmacognostic and Anti-Inflammatory Properties of Securigera securidaca Seeds and Seed Oil

Background and objectives: Although weed plants are considered undesirable in a particular situation, some weed seeds can be a valuable and cheap source of therapeutic natural compounds. Securigera securidaca (L.) Degen & Dorfl (Fabaceae) is widely distributed in Europe, Australia and Asia as a weed plant. This study investigated the bioactive compounds of S. securidaca seeds as well as its potential anti-inflammatory properties. Methods: The fatty acid and sterol content were investigated with gas chromatography–mass spectrometry (GC-MS) and phenolic compounds were detected using high performance thin layer chromatography (HPTLC). The thermostability of the oil was studied using differential scanning calorimetry (DSC). Formalin-induced paw licking test and myeloperoxidase activity were investigated. The study was conducted by creating six groups of rats including a control group (vehicle-treated rats, 250 µL/kg, i.p.), formalin group (50 µL of 2.5% formalin), positive control (paracetamol, 100 mg/kg, i.p), and groups of S. securidaca seed oil (250, 500, 1000, 2000, and 4000 μl/kg, i.p). Results: S. securidaca seeds contained a high level of polyunsaturated fatty acid content including linoleic acid (64.602 ± 0.793%) and oleic acid (15.353 ± 0.461%). Stigmasterol and campesterol were not detected in the oil but it contained esterified β-sitosterol (6.621 ± 0.08 mg/g). The seed oil couldn’t create a significant reduction in the MPO activity. It showed a slight but not significant effect on formalin-induced pain reduction. Conclusion: The seed is a rich source of linoleic acid which makes it a good candidate to be used in the pharmaceutical industry.

Indole alkaloids and anti-nociceptive mechanisms of Tabernaemontana divaricata (L.) R. Br. flower methanolic extract

Flowers of Tabernaemontana divaricata (L.) R. Br., (Apocynaceae) are used in traditional medicine for analgesic property. The present study was performed to isolate the active principles and investigate the mechanisms involved in the anti-nociception caused by T. divaricata flower methanolic extract (TDFME). The extract in the doses of 125, 250 and 500 mg/kg, p.o was subjected to various assays in acetic acid induced abdominal writhing and formalin induced paw licking test models. Naloxone, L-Arginine, Glibenclamide and Glutamate were used as inducers while Morphine, L-NAME, Methylene blue and Aspirin served as standard drugs. The phytochemical analysis led to the isolation of three indole alkaloids namely Voacangine, Catharanthine and O-acetyl Vallesamine. The anti-nociception produced by TDFME was attenuated significantly (p< 0.001) by the intra-peritoneal pretreatment of naloxone, L-Arginine and glibenclamide. The nociception produced by glutamate was inhibited by TDFME. TDFME also enhanced the antinociceptive activity of L-NAME when given in combination. However TDFME co-administration did not produce significant results with methylene blue indicating lack of cGMP involvement. These results indicate that TDFME produces anti-nociception action mediated by opioid, nitric oxide, K+-ATP and glutamate mechanisms and the effect is largely related to the indole alkaloids.

Ethanolic extract of the aerial parts of Passiflora cincinnata Mast. (Passifloraceae) reduces nociceptive and inflammatory events in mice

BackgroundPassiflora cincinnata Mast. is described as a native species from the Caatinga biome, and used by traditional medicine for several pharmacological purposes, such as inflammatory disorders. However, studies that prove its biological activities are scarce. Hypothesis/purposeThis paper aims to evaluate the antinociceptive and anti-inflammatory activities of the aerial parts of Passiflora cincinnata (Pc-EtOH) in mice. MethodsThe chemical composition of Pc-EtOH was assessed by high-performance liquid chromatography coupled to diode array detector (HPLC-DAD). The antinociceptive profile of the extract (given orally: 100, 200 and 400 mg/kg) was established using the in vivo chemical models (acetic acid-induced abdominal constriction and formalin-induced paw licking test) and thermal (hot plate test) of nociception. The role of opioid, potassium channels, TRPV-1, muscarinic, serotoninergic (5-HT3) receptors and the participation of the nitric oxide pathway also was determined. The rota-rod test was used to verify the possible interference of the extract treatment in motor performance. Paw edema induced by carrageenan or histamine, and leukocyte migration, determination of total protein and nitric oxide to the peritoneal cavity were used for anti-inflammatory profile. ResultsThe presence of flavonoids in the extract was confirmed using HPLC-DAD. At all doses tested the Pc-EtOH significantly reduced the number of writhing and decreased the paw licking time in both phases of the formalin test (p < 0.05). In the hot plate test, the extract increased the reaction time, reducing painful behavior. The antinociceptive mechanism probably involves central and peripheral pathways, involving the pathway of opioid and muscarinic receptors with influence of potassium channels and the nitric oxide pathway. However, the motor coordination test indicated that in the time of 120 min the extract decreases the stay time of the animal in the rota-rod. Pc-EtOH inhibited significantly (p < 0.05) the increase of the edema volume after administration of carrageenan and histamine. In the peritonitis test, acute pre-treatment with Pc-EtOH inhibited leukocyte migration, with a reduction in the number of neutrophils and concentration of total proteins and nitric oxide. ConclusionThe present study suggests that Pc-EtOH possesses peripheral and central antinociceptive action, and showed potential in inhibition of release of mediators of the inflammatory process.

Anti-nociceptive effect of seed extract of Acacia tortilis in rodents

Background: Management of pain is a primary clinical concern for any pathology in medical field. Addiction liability of opioids and troublesome gastrointestinal side effects of NSAIDs leads to intensive research for compound with lesser side effects.The aim of the study to evaluate the anti-nociceptive activity of Acacia Tortilis Seed Extract (ATE) in experimental animals.Methods: First of all, animals were randomly allocated into four groups of six animals each. In acetic acid induced writhing test model, Group I (NC) served as vehicle control received saline/Tween 80 0.1%, 10ml/kg BW orally, group II (ATE-100) and III (ATE-200) received ATE in dose of 100 and 200mg/kg BW orally respectively and group IV received the standard drug diclofenac sodium in dose of 50 mg/kg BW orally. Group I to IV were same in rest of three experimental models. One additional group of standard drugs (group V) morphine sulfate in dose of 5 mg/kg BW subcutaneously (SC) was allocated for screening method hot plate and tail flick tests. In Formalin induced paw licking test, three additional groups (group V) morphine sulfate in dose of 5mg/kg BW SC, group VI- morphine+naloxone (5mg/kg SC +2mg/kg intra-peritoneally (IP) and group VII - ATE+ naloxone (200mg/kg BW orally +2mg/kg BW IP) were also made.Results: The ATE when administered orally in dose of 100 and 200mg/ kg body weight (BW), produced significant analgesic activity (P &lt;0.01) in acetic acid induced writhing syndrome and late phase of formalin test. In the hot plate test in mice and tail flick test in rats, ATE in same doses also showed significant analgesic activity (P &lt;0.05) which is almost equally efficacious to standard drug diclofenac sodium (50mg/kg BW orally) but far less efficacious than morphine sulfate (5mg/kg BW subcutaneous).ATE (200mg/Kg BW orally) activity did not blocked by naloxone (2mg/kg intra-peritoneal).Conclusions: ATE possesss significant anti-nociceptive activity as evidenced in all the animal models of nociception. It might exert its effect through the peripheral mechanism of analgesic action possibly by interference in biosynthesis, release and/or action of prostaglandins and leukotrienes.

Antinociceptive activity of Inula britannica L. and patuletin: In vivo and possible mechanisms studies

Ethnopharmacological relevanceInula britannica L. is a predominant medicinal plant traditionally utilized in the treatments of arthritis and back pain in Iranian folk medicine. Aim of the studyThe purpose of this research was to evaluate the antinociceptive effects of Inula britannica L. flower essential oil (IBLEO) and one of its major constituents, Patuletin (Pn), in male mice. Materials and methodsIn this study, we used pain assessment tests including acetic acid-induced writhing, tail-flick (TF), formalin induced paw licking (FIPL) model, and glutamate-induced paw licking (GPL). For understanding the supposed antinociceptive mechanisms of IBLEO, opioid and L-arginine/NO/cGMP/ KATP pathways were examined. ResultsIn the TF, writhing, GPL, and FIPL tests, a dosage of 100 mg/kg of IBLEO showed noteworthy antinociceptive effects in comparison with control (p < 0.05). In writhing test, administration of selective opioid antagonists (naltrindole, nor-binaltorphimine, and naloxonazine) attenuated the antinociceptive effect of IBLEO in comparison with control (p < 0.001). Both methylene blue and glibenclamide blocked the antinociceptive effect of IBLEO (p < 0.05), but the administration of L-arginine or sodium nitroprusside fundamentally potentiated the antinociception induced by IBLEO in phase II of the FIPL (p < 0.05). Additionally, patuletin showed significant antinociceptive effects in writhing, FIPL, and GPL tests (p < 0.01). ConclusionThe results of this examination showed that IBLEO and Pn have antinociceptive effects. The modulation of glutamatergic systems by opioid receptors could be involved, at least in part, in these effects. Our data also suggest the activation of the L-arginine/NO/cGMP/KATP pathway in IBLEO antinociceptive effects.

Anti-nociceptive mechanisms of flavonoids-rich methanolic extract from Terminalia coriacea (Roxb.) Wight & Arn. leaves

In view of the report on anti-nociceptive activity of Leathery Murdah, Terminalia coriacea {Roxb.} Wight & Arn. (Combretaceae) leaves, the present study was conducted to isolate the active constituents and identify the underlying mechanisms. The methanolic extract of T. coriacea leaves (TCLME) at doses 125, 250 and 500 mg/kg orally, was subjected to various in-vivo assays in acetic acid induced writhing and formalin induced paw-licking tests with aspirin (100 mg/kg) and morphine (5 mg/kg) as reference drugs. Three flavonoids, rutin, robinin and gossypetin 3-glucuronide 8-glucoside were isolated and characterized from TCLME for the first time. The extract showed significant (p < 0.001) dose-dependent anti-nociceptive activity in glutamate induced paw licking in mice. The involvement of opioid pathway was confirmed as naloxone (5 mg/kg, i.p) treatment blocked the analgesic activity of the test extract. Similarly, glibenclamide (an ATP - sensitive potassium channel inhibitor) at dose of 10 mg/kg, i.p increased writhing in acetic acid model. It reversed the inhibitory effects of TCLME when administered in combination. Treatment of TCLME alone and in combination with l-arginine (100 mg/kg, i.p) significantly (p < 0.001) reduced writhing while pre-treatment with l-NAME (20 mg/kg, i.p) further enhanced the analgesic action of TCLME indicating involvement of nitric oxide pathway.

An in vivo study regarding analgesic and anxiolytic activity of methanolic extract of Typha elephantina Roxb

BackgroundTypha elephantina Roxb. is a widely scattered grass like medicinal plant in Bangladesh and thus demands biological investigations to discover its therapeutic potentiality. The aim of our present study was to assess analgesic and anxiolytic properties of methanolic extract of Typha elephantina Roxb.MethodsFor evaluating analgesic activity, the methanolic extract was subjected to intraperitoneally (i.p.) administered acetic acid-induced writhing test & subcutaneously administered (s.c.) formalin-induced hind paw licking test in Swiss-albino mice. The anxiolytic activity was conducted by using elevated plus maze (EPM) and hole board models.ResultsFor both methods of analgesic test experimental plant extract was found to have significant (p < 0.001) analgesia at the dose of 200 mg/kg & 400 mg/kg body weight in mice when compared to control, where acetyl salicylic acid (100 mg/kg body weight) was used as standard drug. The percentages of inhibition found in case of acetic acid-induced writhing test were 26.27%, 50.45% and 20.29% respectively for acetyl salicylic acid (100 mg/kg), 200 mg/kg extract dose and 400 mg/kg extract dose. On the other hand, during formalin-induced hind paw licking test, the percentages of inhibition also increased when the extract dose increases from 200 mg/kg to 400 mg/kg by 53.95% to 61.79% at early phase and 71.62% to 78.8% at late phase respectively while acetyl salicylic acid (100 mg/kg), responsible for 25.58% and 38.74% of inhibition at both phase sequentially. Again, the crude extract significantly (p < 0.01; p < 0.001) raised the time spent in the open arm (149.2 ± 27.63** sec) & the number of head-dips (50.00 ± 4.66***) at the dose 400 mg/kg body weight in case anxiolytic test, while reference drug diazepam (1 mg/kg body weight) also exhibited significant (p < 0.01) result in case of time spent in open arm (107.0 ± 12** sec) but not for head dipping (14.83 ± 1.6).ConclusionFindings of the present study assure that Typha elephantina Roxb. may be effective for the treatment of pain and anxiety with the demands of further investigations to isolate the active compound(s).

Anti-nociceptive effect of methanol extract of leaves of Senna singueana in mice

Ethnopharmacological RelevanceSenna singueana (Del.) Lock (Fabaceae) is a shrub or tree found in Ethiopia and other African countries. It has been traditionally used for different conditions including treatment of pain conditions in humans and animals. Although various reports are available in the literature claiming different activities of the plant, scientific studies supporting analgesic potential of S. singueana are lacking and the present study aimed to investigate the antinociceptive effect of methanol extract of leaves of S. singueana in mice. Materials and MethodsAnti-nociceptive activity of S. singueana (200 mg/kg and 400 mg/kg, p.o) was investigated using acetic acid-induced writhing, formalin-induced paw licking, and hot plate tests. Acute oral toxicity was determined using a slightly modified guideline (423) of the Organization for Economic Cooperation and Development. ResultsS. singueana extract increased the percentage of inhibition of writhing response and licking response (neurogenic and inflammatory phase) in acetic acid-induced writhing and formalin-induced paw licking tests, respectively. It also significantly (p ≤ 0.05) increased the percentage of mean maximal effect (%MPE) compared to control group in the hot-plate test. In all models, the combination of S. singueana with either diclofenac or morphine produced statistically significant increase (p ≤ 0.05) in the percentage of inhibition of writhing, paw licking, and %MPE compared to single treatment groups. It was also found that the 400 mg/kg extract produced higher antinociceptive effects (p ≤ 0.05) compared to the 200 mg/kg. ConclusionS. singueana leaves may have analgesic effect that is mediated through both peripheral and central mechanisms and could be used as adjuvant treatment to the modern analgesics.

Analgesic and Anti-Inflammatory Activities of Diethyl Ether and n-Hexane Extract of Polyalthia suberosa Leaves.

In folk medicine, Polyalthia suberosa is used as abortifacient, laxative, febrifuge analgesic, filler of tooth cavities, and anti-HIV drug and for rheumatism and various skin infections. The present study was directed to evaluate the analgesic and anti-inflammatory activities of diethyl ether and n-hexane extracts of Polyalthia suberosa leaves (PSDE and PSNH). A variety of tests including formalin-induced paw licking test, acetic acid induced writhing test, and tail immersion test were used to assess the analgesic activity. In addition, xylene-induced ear edema test was used to evaluate anti-inflammatory activity of PSDE and PSNH. PSDE and PSNH at 200 and 400 mg/kg doses expressed analgesic as well as anti-inflammatory activities in mice. In formalin-induced paw licking test, acetic acid induced writhing test, and xylene-induced ear edema test, the extracts exhibited significant inhibition (⁎P < 0.05 versus control) of pain and inflammation. Alternatively, in tail immersion test, PSDE 400 mg/kg showed significant (⁎P < 0.05 versus control) latency at 30 min but another tested sample had no significant latency. From this study, it could be shown that Polyalthia suberosa leaves may contain analgesic and anti-inflammatory agents which support its use in traditional medicine.