Tail Flick Research Articles

In vivo pharmacokinetic, pharmacodynamic and brain concentration comparison of fentanyl and para-fluorofentanyl in rats.

In 2022, para-fluorofentanyl (pFF) rose to the 6th most reported drug and the most reported fentanyl analog in the United States according to the Drug Enforcement Administration (DEA). pFF differs from fentanyl by the addition of a single fluorine group. To date, pFF has not been extensively evaluated in vivo and is frequently seen in combination with fentanyl. In the present study, the pharmacodynamic (PD) and pharmacokinetic (PK) properties and brain region-specific concentrations of pFF were evaluated in male Sprague-Dawley rats and compared to fentanyl. A 300μg/kg subcutaneous dose of fentanyl or pFF was administered to assess PD and PK parameters as well as brain region concentrations. PD parameters were evaluated via a tail flick test to evaluate analgesia and core body temperature to measure hypothermia, a surrogate marker of overall opioid toxicity. Fentanyl and pFF were found to be equally active at the tested dose in terms of tail flick response with both compounds producing an analgesic response that lasted up to 240min post-drug treatment. pFF induced a significantly greater hypothermic effect compared to fentanyl with a maximum temperature decrease of -5.6 ℃. Plasma PK parameters (T1/2, AUC, etc.) did not differ between fentanyl and pFF. However, pFF concentrations in the medulla, hippocampus, frontal cortex and striatum were more than two times the fentanyl concentrations. The increase in brain concentrations and greater hypothermic effect suggests that pFF is potentially more dangerous than fentanyl.

Measurement of the Direct Impact of Hematophagous Flies on Feeder Cattle: An Unexpectedly High Potential Economic Impact.

In addition to blood pathogen transmission, insects of the order Diptera affect livestock through visual and contact harassment; blood-feeders are responsible for painful bites and blood despoliation, generating behavioral modifications, anemia, and production losses. Knowledge of their economic impact is a basis for cost-effective control. Here, we measured the global impact of diptera insects by comparing two batches of six feeder cattle, one in the open air and the other protected by a mosquito net. The analytical data were insect density in the open air and, for feeder cattle, tail flick counts, hematocrit values (Ht), feed intake, feed conversion ratio (FCR), and live body weight gain (LBWG). Over a period of five months, the results showed significant losses in the LBWG of cattle exposed to insects, estimated at 8.0 ± 1.5 kg/month [2.7; 13.3], with a total loss reaching 40.0 ± 5.5 kg/head. Main diurnal insects were Stomoxys spp. and Musca crassirostris. There was a strong correlation between fly density and diurnal tail flicks. Night trapping and tail flicks showed a potentially important role of mosquitoes to be further explored. The Ht levels of exposed animals were 3-4% lower than those of controls. FCRs indicated that exposed animals needed 33% more dry matter intake/kg of LBWG. An economic assessment showed that dipterans were responsible for a 10-11% loss in LBWG during the main growing period of feeder cattle (10-15 months). A feedlot of 100 calves would register a total loss of USD 16,000 within 5 months, which appears to be an unexpectedly huge loss caused by dipterans. Investing part of this money into fly control would probably be beneficial.

A Patent-Pending Ointment Containing Extracts of Five Different Plants Showed Antinociceptive and Anti-Inflammatory Mechanisms in Preclinical Studies.

Background/Objectives: The antinociceptive and anti-inflammatory effects of a patent-pending ointment containing plant extracts from Eucalyptus globulus, Curcuma longa, Hamamelis virginiana, Echinacea purpurea, and Zingiber officinale were evaluated. Methods: Plant extracts were chemically characterized by gas chromatography-mass spectroscopy. The antinociceptive activity of the ointment was assessed using the hot plate, tail flick, and formalin tests, whereas the anti-inflammatory activity was measured using the acute and chronic TPA-induced ear edema tests. Mechanisms of action were evaluated using inhibitors from signaling pathways related to pain response and by using histological analysis and assessing the expression and activity of pro-inflammatory mediators. Results: The ointment showed antinociceptive and anti-inflammatory effects like those observed with diclofenac gel (1.16% v/v) and ketoprofen gel (2.5% v/v). The antinociceptive actions of the ointment are mediated by the possible participation of the opiodergic system and the nitric oxide pathway. The anti-inflammatory response was characterized by a decrease in myeloperoxidase (MPO) activity and by a reduction in ear swelling and monocyte infiltration in the acute inflammation model. In the chronic model, the mechanism of action relied on a decrease in pro-inflammatory mediators such as COX-2, IL-1β, TNF-α, and MPO. An in-silico study with myristic acid, one of the compounds identified in the ointment's plant mixture, corroborated the in vivo results. Conclusions: The ointment showed antinociceptive activities mediated by the decrease in COX-2 and NO levels, and anti-inflammatory activity due to the reduction in IL-1β and TNFα levels, a reduction in MPO activity, and a decrease in NF-κB and COX-2 expression.

Nano-pregabalin effectively mitigates Glut, CGRP and NE neurotransmitters abnormalities in the brain of gamma irradiated rats with reserpine-induced fibromyalgia model: Behavioral and neurochemical studies

AimsFibromyalgia (FM) is an idiopathic syndrome with painful burdensome symptoms. Radiotherapy is one of the main therapeutic modalities for treating various malignancies and there is a probable association between FM exacerbation and exposure to ionizing radiation. Based on that nanomedicines progressively being explored for their promising applications in medicine, the aim of the current study is to assess the possible therapeutic benefits of nanoform of pregabalin (N-PG) in managing FM symptoms during being exposed to ionizing radiation. Main methodsRats were allocated into four groups. First group served as control, the other three groups received gamma radiation (2 Gy/day) after 1 h of reserpine administration (1 ml/kg per day, s.c.) to induce FM for three successive days. On the next day, third and fourth groups received (30 mg/kg, p.o.) of PG and N-PG, respectively once daily for ten consecutive days. Tail flick test was performed and von Frey filaments were used to assess mechanical allodynia/hyperalgesia, and then rats were sacrificed to obtain brains. Key findingsN-PG effectively replenished reserpine effects and treated both allodynia and hyperalgesia, improved thermal allodynia, effectively recovered all neurotransmitters near to normal baseline, inhibited oxidative stress status via decreasing malondialdehyde (MDA), increasing glutathione (GSH) and superoxide dismutase (SOD), it had strong anti-inflammatory effect as verified by reducing both cyclooxygenase-2 (COX-2) and nuclear factor kappa B (NF-kB) in addition to inhibition of intrinsic apoptosis through caspase-3 (casp-3) decrease and B-cell lymphoma-2 (Bcl-2) increase. Histopathological and immunohistochemical results confirmed the biochemical findings. SignificanceN-PG could be a promising drug for treating FM especially when there is urgent need to expose patient to ionizing radiation.

479 Pain control for the castration of newborn bull calves by elastration

Abstract All methods of castration are known to cause pain regardless of the method, or age of the animal. Our objective was to explore providing pain control for bull calves castrated by elastration prior to 1 wk of age. Singleton, bull calves (n = 85) born at the Ontario Beef Research Centre were enrolled and randomly assigned to 1 of 5 treatment groups at birth: a single dose of oral meloxicam at castration (1ORAL), a dose of oral meloxicam at castration and a second oral dose 1 wk later (2ORAL), a dose of injectable meloxicam at castration (1INJECT), not castrated (SHAM), or castrated without pain control (PAINFUL). Calves were treated within 48 h of birth and followed until weaning. All calves were observed 2 h/d for 13 different pain-associated behaviors (e.g., tail flicks, kicking, licking the scrotum) on the day of castration (d 0), as well as d 1, 2, 7, 8, and 9. To record general activity, from d -1 to d 14 each calf wore an Onset HOBO Pendant G Data Logger attached to one of their hind legs. Calves were weighed weekly until they were turned-out to pasture and thereafter weighed bi-weekly until weaning. Five behaviors were statistically significant between treatment groups. PAINFUL calves had roughly three times the rate of licking (P > 0.05) compared with calves in 1ORAL, 2ORAL, and 1INJECT groups, and four times the rate of licking compared with SHAM calves. Additionally, PAINFUL calves had two times the rate of tail flicks (P < 0.05) compared with meloxicam-treated calves, and five times the rate of tail flicks compared with SHAM calves. A treatment effect (P < 0.05) was observed for standing time, with PAINFUL calves spending the least amount of time standing on average in a 24-h period. No statistical time differences were seen between the remaining treatment groups. No treatment or treatment*time interaction effects were observed for lying time. A tendency was seen for treatment effect on lying time (P = 0.0581), with PAINFUL calves spending the most time lying on average and having a significance difference compared with all other treatment groups (LSM > 0.05). No treatment effect was seen for average daily gain up to wk 8, and for final weaning weights. Weight at time of castration was significant (P < 0.05); however, calves were not blocked by BW when assigned to treatment. In conclusion, meloxicam-treated calves expressed decreased rates of pain-associated behaviors compared with PAINFUL calves, and BW did not differ at time of weaning. Our results provide evidence that calves castrated by elastration before 1 wk of age and received meloxicam, experience less pain.

Comparative Experimental Study of using Tramadol & Nefopam in Pain Management.

Pain is a disturbing sensory and emotive sentiment triggered mainly by tissue-damaging stimuli. This study aimed to evaluate the potential effect of tramadol and nefopam on acute pain. Thirty Sprague-Dawley rats (each 200-250 g) were randomly allocated into three sets (n=10). The nefopam group was treated with nefopam (3.5 mg/kg) by intraperitoneal (IP) injection; the tramadol group was given tramadol (50mg/kg) by IP injection, and the control group was treated with normal saline. Two main methods were proposed for assessing and monitoring rat pain: hot plate and tail-flick techniques using tail immersion. It was revealed a significant change (p<0.0001) in the outcome in the animal groups that received nefopam (3.5mg/kg/IP) and tramadol (50mg/kg/IP) in the prospect of hot plate test (hand paw lick parameter) and tail flick test. Regarding the hot plate test (jumping parameter), there was no significant change (p>0.05) in animals treated with tramadol and nefopam compared to the control group. Moreover, a considerable difference between the hot plate test (hand paw lick parameter) and the tail-flick test was detected between tramadol and nefopam-treated groups. However, no significant variance (P=0.101) was detected between the two groups in the hot plate test (jumping parameter). Tramadol showed better analgesic activity over nefopam in suppressing pain stimuli in acute settings with modest to severe pain, making tramadol a favourable choice for short-term management of postoperative pain.

Modulatory Effects of Morphine and Xylopia aethioica Extract on Kappa Opiod Receptors (KOR), Delta Opioid Receptor (DOR), Pain Hypersensitivity and Motor Functions in Wistar Rats

This study investigates the modulatory effects of morphine and Xylopia aethiopica extract on kappa opioid receptors (KOR), delta opioid receptors (DOR), pain hypersensitivity, and motor functions in Wistar rats. We utilized three experimental groups: a control group receiving distilled water, a morphine group receiving either low (5 mg/kg) or high (10 mg/kg) doses after inducing pain, Xylopia aethiopica group received either 25 mg/kg or 50 mg/kg of hydromethanolic extract following similar pain induction. Pain perception was quantified using the tail flick test and Analgesy-Meter while motor functions were assessed through the Rotarod and Climbing/Beam Walk tests. Additionally, molecular docking studies were performed on selected compounds from Xylopia aethiopica to determine their binding affinities to opioid receptors using Vina. Results demonstrated that morphine and Xylopia aethiopica significantly increased tail flick response times, indicating notable analgesic effects, while improving motor functions particularly in animals treated with higher doses of Xylopia aethiopica. Molecular analysis revealed potential interactions between bioactive compounds and opioid receptors, suggesting further therapeutic applications. These findings highlight the potential of Xylopia aethiopica as a natural analgesic and its implications in managing pain and associated motor deficits, the findings further revealed that Morphine and not Xylopia aethiopica is implicated in pain hypersensitivity after long term exposure. Further research should pay attention on improving the pharmacological profiles of the identified compounds for clinical use.

Artemisinin and deoxyartemisinin isolated from Artemisia annua L. promote distinct antinociceptive and anti-inflammatory effects in an animal model

Artemisia annua L., known for antimalarial activity, has demonstrated evidence of anti-inflammatory potential. Previously our research group reported the anti-inflammatory and antinociceptive effect of a sesquiterpene lactone-enriched fraction (Lac-FR) obtained from plant, containing artemisinin and deoxyartemisinin. Both the isolated compounds and Lac-FR evaluated on experimental animal models, in the formalin test showed that deoxyartemisinin reduced both neurogenic pain (56.55 %) and inflammatory pain (45.43 %). These findings were superior to the effect of artemisinin (reduction of 28.66 % and 33.35 %, respectively). In the tail flick test, the antinociceptive effect reported as a percentage of the maximum possible effect (%MPE), deoxyartemisinin showed a lower antinociceptive effect (41.57 %) compared to morphine (75.94 %) in 0.5 h. After 1.5 h, the MPE of deoxyartemisinin (87.99 %) exceeded the effect of morphine (47.55 %), without reversal with naloxone. The MPE of artemisinin (23.3 %) observed after 2 h was lower than deoxiartemisinin, without reversal with the opioid antagonist. Lac-FR and artemisinin demonstrated reductions in ear edema of 43.37 % and 48.19 %, respectively, higher than the effect of deoxyartemisinin (33.64 %). Artemisinin reduced tumor necrosis factor alpha (TNF-α) (76.96 %) more selectively when compared to interleukin-1beta (IL-1β) (48.23 %) and interleukin-6 (IL-6) (44.49 %). Lac-FR showed greater selectivity in IL-6 reduction (56.49 %) in relationship to TNF-α (46.71 %) and IL-1β (45.12 %), whereas deoxyartemisinin selectively reduced TNF-α (37.37 %). The results of our study indicate that the lactones isolated did not have relationship with the opioid system. Deoxyartemisinin showed a higher antinociceptive potential than artemisinin. Whereas, artemisinin showed a higher reduction of inflammation and mediators, with a better anti-inflammatory activity outcome.

Investigating the Analgesic Effect of Flavonoid Rich Fraction from Pteris quadriaurita: Evidence from In-silico, In-vitro and In-vivo Studies

Pteris quadriaurita, a highly significant underutilized plant species that was widely recognized for its ethnobotanical and ethnomedicinal properties. The work aimed to estimate the flavonoid-rich fraction of P. quadriaurita (PQFRF), which was typically used to alleviate pain, for its antioxidant profile and associated analgesic effectiveness. In-silico molecular docking and PRIME MM-GB/SA studies were performed to analyze the binding pattern of nine bioactive substances identified by gas chromatography-mass spectrometry (GC-MS). The plant’s antioxidant activities were tested in-vitro using DPPH, ferricreducing antioxidant power, Superoxide anion radical, and hydroxy radical scavenging tests. For in-vivo analgesic research, the hot plate model, acetic acid-induced writhing, and tail flicking models were utilised. PQFRF was found to be equipotent to the reference medication in the studied peripheral and central analgesic models at a maximal dose of 50 mg/kg.

Comparison of Thermal and Mechanical Pain Testing Modalities in Sprague Dawley and Fischer 344 Rats (Rattus norvegicus).

While rodents are used extensively for studying pain, there is a lack of reported direct comparisons of thermal and mechanical pain testing methods in rats of different genetic backgrounds. Understanding the range of interindividual variability of withdrawal thresholds and thermal latencies based on these testing methods and/or genetic background is important for appropriate experimental design. Testing was performed in two common rat genetic backgrounds: outbred Sprague-Dawley (SD) and inbred Fischer 344 (F344). Male and female, 10- to 14-wk-old F344 and SD rats were used to assess withdrawal thresholds in 3 different modalities: the Randall-Selitto test (RST), Hargreaves test (HT), and tail flick test (TFT). The RST was performed by using an operator-controlled handheld instrument to generate a noxious pressure stimulus to the left hind paw. The HT and the TFT used an electronically controlled light source to deliver a noxious thermal stimulus to the left hind paw or tail tip, respectively. Rats of each sex and genetic background underwent one type of test on day 0 and day 7. Withdrawal thresholds and thermal latencies were compared among tests. No significant differences were observed. Our findings can serve as a guide for researchers considering these nociceptive tests for their experiments.

Phytochemical and pharmacological profiling of extracts of Pterygota alata (Roxb.) R. Br. leaves deciphered therapeutic potentialities against pain, hyperglycemia and diarrhea via in vivo approaches

Background and aimPterygota alata (Roxb.) R. Br. is a large, broad-leaved evergreen plant in the family Malvaceae (formerly Sterculiaceae). The present study aimed to investigate the phytochemical and pharmacological properties of methanolic extract of the leaves (200 mg/kg bw and 400 mg/kg bw) of P. alata focusing on analgesic, hypoglycemic, and anti-diarrheal potentials on the Swiss Albino mice model. MethodsGas chromatography and mass spectrometry (GC-MS) technique was employed to identify the bioactive compounds from the plant species. The tail flicking procedure and acetic acid-induced writhing inhibition were carried out to estimate central and peripheral analgesic properties. The anti-diarrheal property of the herbaceous extractive was assessed employing the castor oil-induced antidiarrheal approach, while the hypoglycemia was estimated employing the tail-tipping method. ResultsThe study reported a total of thirty-seven phytoconstituents by using GC-MS analysis, where erucamide (25.5 %), 8,11,14-Docosatrienoic acid, methyl ester (14.58 %), methyl linoleate (12.67 %), and methyl palmitate (9.23 %) were most abundant in the plant species. In evaluating central analgesia, the leaf extract of P. alata exerted significant central analgesic (200 mg/kg bw and 400 mg/kg bw) efficacy. The acetic acid-induced writhing was inhibited by 45.84 % and 66.67 % at both doses, demonstrating a promising peripheral analgesic effect compared to diclofenac sodium (75.00 %). On the contrary, hypoglycemic actions remained dosage and time-dependent. In the antidiarrheal activity assay, the number of diarrheal feces was reduced significantly by 40.00 % (200 mg/kg) and 68.00 % (400 mg/kg), correspondingly, which was comparable to the positive control loperamide (72.00 %). In addition, the study of acute oral toxicity revealed that the extracts of the plant species were found to be safe, with a median lethal dose (LD50) value greater than 1000 mg/kg. ConclusionThe current study supports the assertion that the P. alata plant species is rich in numerous phytoconstituents and has the potential for traditional application in managing pain, hyperglycemia, and diarrhea. Nonetheless, additional investigation is necessary to extract and identify the bioactive compounds from the plant, which is crucial for advancing the discovery of novel medicinal compounds aimed at addressing a range of health conditions.

Analgesic and Anti-inflammatory Potential of the New Tetrahydropyran Derivative (2s,6s)-6-ethyl-tetrahydro-2h-pyran-2-yl) Methanol.

The development of analgesic and anti-inflammatory drugs plays a crucial role in modern medicine, aiming to alleviate pain and reduce inflammation in patients. Opioids and nonsteroidal anti-inflammatory drugs are groups of drugs conventionally used to treat pain and inflammation, but a wide range of adverse effects and ineffectiveness in some pathological conditions leads us to search for new drugs with analgesic and anti-inflammatory properties. In this regard, the authors intend to investigate the ((2s,6s)-6-ethyl-tetrahydro-2h-pyran- 2-yl) methanol compound (LS20) on pain and acute inflammation. Male Swiss mice were evaluated using acetic acid-induced abdominal writhing, formalin, and tail-flick as models of nociceptive evaluation and edema paw, air pouch and cell culture as models of inflammatory evaluation besides the rotarod test for assessment of motor impairment. The compound showed an effect on the acetic acid-induced abdominal writhing, formalin and tail-flick tests. Studying the mechanism of action, reversion of the antinociceptive effect of the compound was observed from previous intraperitoneal administration of selective and non-selective opioid antagonists on the tail flick test. In addition, the compound induced an antiedematogenic effect and reduced leukocyte migration and the production of pro-inflammatory cytokines in the air pouch model. LS20 was able to maintain cell viability, in addition to reducing cell production of TNF-α and IL-6. In summary, the LS20 compound presented an antinociceptive effect, demonstrating the participation of the opioid system and an anti-inflammatory effect related to the inhibition of pro-inflammatory cytokine production. The compound also demonstrated safety at the cellular level.

Screening for Antinociceptive Action of Gastroretentive Drug delivery System of Tramadol hydrochloride in Mice

The floating drug delivery system is to avoid the problem of drug waste and to limit the frequency of administration. Here the drug Tramadol is being centrally acting opioid analgesic can be formulated as sustained release formulation by adopting the method gastroretentive drug delivery system through effervescent floating drug delivery system with different grades of polymer Hyperomellose. The Pharmacological activity on Mice by both Hot Plate and Tail Flick Methods also suggest that when the Tramadol Hcl increased with its dosage form shows significant Analgesic Activity in animals which shows a spontaneous dose dependent increase in Analgesic activity was found it shows that the dosage form deserve for designed method of gastroretentive drug delivery system.

Aerodynamic breakup of gel suspension droplets loaded with aluminum particles

The persistent and frequent space explorations are affected by the performance of propellants, among which the closely related gel propellants have been widely used due to their unique characteristics. Currently, research efforts primarily concentrate on the metallization and atomized combustion of gel propellants, emphasizing the combustion performance of metallized gel propellants. However, little attention has been given to the secondary breakup process that occurs just before combustion. By utilizing high-speed flow visualization technology, this study examines the key aerodynamic breakup process of gel suspension droplets loaded with micro aluminum particles, experimentally and theoretically investigating the droplet dynamics induced by particle volume fraction. The experimental confirmation of the three breakup behaviors exhibited by gel suspension droplets, namely oscillation mode, bag-stamen breakup, and hemline breakup, is presented along with the construction of a phase diagram. The impact of heterogeneous effects resulting from an increase in particle volume fraction on the critical breakup Weber number is revealed, with a concentration of 9 % as the turning point. Within the range of moderate Weber numbers, the tail flick deformation of suspension droplets in airflow is observed and reported for the first time. At different particle concentrations, there keeps a linear correlation between the dimensionless tail length and Weber number. Spherical suspension droplets will deform into thin disks in the airflow, with a nearly constant deformation rate regardless of changes in particle concentration. Additionally, the relationships between characteristic times and droplet parameters are discussed through statistical analysis of the results. As Ohnesorge number and particle volume fraction increase, the characteristic times both show a monotonically increasing trend. Moreover, a model of unstable growth rate associated with the particle volume fraction is established through linear instability analysis, accurately predicting the variation in critical Weber number for gel suspension droplet breakup. The congruence between our theoretical framework and experimental findings not only enhances comprehension of the impact of micro aluminum particles on the secondary breakup of gel suspension droplets but also provides valuable guidance for the aerospace applications of metallized gel propellants.

Evaluation of New Approaches to Depression Treatment Using an Animal Model of Pharmacoresistant Depression.

Depression is emerging as the predominant psychiatric disorder globally. Despite the wide availability of antidepressants, up to 30% of patients exhibit poor response to treatment, falling into the category of treatment-resistant depression (TRD). This underscores the need for the exploration of novel therapeutic options. Our work aims to study the effect of chronic administration of the pyridoindole derivative SMe1EC2M3, a triple reuptake inhibitor, and the combination of zoletil and venlafaxine under conditions of stress induced by a 4-week chronic mild stress (CMS) procedure in Wistar-Kyoto male rats as an animal model of TRD. Therefore, we investigated the possible effect of the selected compounds in four experimental groups, i.e., stress + vehicle, stress + venlafaxine, stress + zoletil + venlafaxine and stress + SMe1EC2M3. The following variables were assessed: anhedonia in sucrose preference test (SPT), spontaneous locomotion and exploration in open field test (OF), anxiety-like behavior in elevated plus maze test (EPM), motivation and depressive-like behavior in forced swim test (FST) and nociception in tail flick test. We also evaluated cognition, particularly recognition memory, in the novel object recognition test (NOR). Sucrose preference was significantly increased in the SMe1EC2M3 group (p < 0.05) in comparison with the venlafaxine animals. In the OF, we observed a significantly higher number of entries into both the central and peripheral zones in the venlafaxine (p < 0.05 central zone; p ≤ 0.05 periphery zone) and SMe1EC2M3 (p < 0.05 central zone; p < 0.05 periphery zone) groups compared to the venlafaxine + zoletil group. SMe1EC2M3 was able to significantly increase the time of climbing in FST (p < 0.05) in comparison with the venlafaxine and control groups. The NOR test revealed a significantly higher discrimination ratio in the SMe1EC2M3 group (p < 0.05) compared to the control and venlafaxine groups. Analyses of the tail flick test showed a significant increase in reaction time to painful stimuli in the SMe1EC2M3 group (p < 0.05) in comparison to both the control and venlafaxine groups. Our findings suggest that SMe1EC2M3 has the potential to ameliorate some behavioral changes associated with TRD, and the venlafaxine + zoletil combination treatment was not a promising treatment alternative in the animal model of TRD.

Bioassay-guided isolation of anti-inflammatory and antinociceptive metabolites among three Moroccan Juniperus leaves extract supported with in vitro enzyme inhibitory assays

Ethnopharmacological relevanceHerbs of the genus Juniperus (family Cupressaceae) have been commonly used in ancestral folk medicine known as “Al'Araar” for treatment of rheumatism, diabetes, inflammation, pain, and fever. Bioassay-guided isolation of bioactives from medicinal plants is recognized as a potential approach for the discovery of novel drug candidates. In particular, non-addictive painkillers are of special interest among herbal phytochemicals. Aim of the studyThe current study aimed to assess the safety of J. thurifera, J. phoenicea, and J. oxycedrus aqueous extracts in oral treatments; validating the traditionally reported anti-inflammatory and analgesic effects. Further phytochemical investigations, especially for the most bioactive species, may lead to isolation of bioactive metabolites responsible for such bioactivities supported with in vitro enzyme inhibition assays. Materials and methodsFirstly, the acute toxicity study was investigated following the OECD Guidelines. Then, the antinociceptive, and anti-inflammatory bioactivities were evaluated based on chemical and mechanical trauma assays and investigated their underlying mechanisms. The most active J. thurifera n-butanol fraction was subjected to chromatographic studies for isolating the major anti-inflammatory metabolites. Moreover, several enzymatic inhibition assays (e.g., 5-lipoxygenase, protease, elastase, collagenase, and tyrosinase) were assessed for the crude extracts and isolated compounds. ResultsThe results showed that acute oral administration of the extracts (300–500 mg/kg, p. o.) inhibited both mechanically and chemically triggered inflammatory edema in mice (up to 70% in case of J. thurifera) with a dose-dependent antinociceptive (tail flick) and anti-inflammatory pain (formalin assay) activities. This effect was partially mediated by naloxone inhibition of the opioid receptor (2 mg/kg, i. p.). In addition, 3-methoxy gallic acid (1), quercetin (2), kaempferol (3), and ellagic acid (4) were successfully identified being involved most likely in J. thurifera extract bioactivities. Nevertheless, quercetin was found to be the most potent against 5-LOX, tyrosinase, and protease with IC50 of 1.52 ± 0.01, 192.90 ± 6.20, and 399 ± 9.05 μM, respectively. ConclusionJ. thurifera extract with its major metabolites are prospective drug candidates for inflammatory pain supported with inhibition of inflammatory enzymes. Interestingly, antagonism of opioid and non-opioid receptors is potentially involved.

Analgesic and Anti-Inflammatory Activity: A Comprehensive Review on Invitro and In Vivo Screening Methods

Modern pharmacotherapy includes analgesic and anti-inflammatory medicines as essential components to relieve pain and inflammation brought on by a variety of medical diseases. Robust screening techniques are essential for the identification of possible candidates with appropriate safety and effectiveness profiles in the search and development of new analgesic and anti-inflammatory medications. This study looks at the many screening methods used in preclinical studies to assess new drugs' analgesic and anti-inflammatory quality. Conventional techniques like the tail flick, hot plate, and writhing’s tests measure analgesic activity by having animals respond to unpleasant stimuli. Comparably, anti-inflammatory activity is frequently assessed using assays like the cotton pellet granuloma test, which gauges tissue granuloma formation, and the carrageenan-induced paw edema model, which measures inflammation. These traditional techniques offer insightful information about the pharmacological effects of test substances. Despite the wide range of screening techniques available, each strategy has advantages and disadvantages. Preclinical studies are more reliable and have higher predictive value when various assays and techniques are integrated into a tiered screening strategy. Furthermore, the successful translation of preclinical findings to human applications depends on taking into account translational variables including species differences and clinical relevancies. As a result, choosing the right screening techniques is critical to the effective identification and characterization of new analgesic and anti-inflammatory drugs.

The Analgesic Potential of Litsea Species: A Systematic Review.

Various plant species from the Litsea genus have been claimed to be beneficial for pain relief. The PRISMA approach was adopted to identify studies that reported analgesic properties of plants from the Litsea genus. Out of 450 records returned, 19 primary studies revealed the analgesic potential of nine Litsea species including (1) Litsea cubeba, (2) Litsea elliptibacea, (3) Litsea japonica, (4) Litsea glutinosa, (5) Litsea glaucescens, (6) Litsea guatemalensis, (7) Litsea lancifolia, (8) Litsea liyuyingi and (9) Litsea monopetala. Six of the species, 1, 3, 4, 7, 8 and 9, demonstrated peripheral antinociceptive properties as they inhibited acetic-acid-induced writhing in animal models. Species 1, 3, 4, 8 and 9 further showed effects via the central analgesic route at the spinal level by increasing the latencies of heat stimulated-nocifensive responses in the tail flick assay. The hot plate assay also revealed the efficacies of 4 and 9 at the supraspinal level. Species 6 was reported to ameliorate hyperalgesia induced via partial sciatic nerve ligation (PSNL). The antinociceptive effects of 1 and 3 were attributed to the regulatory effects of their bioactive compounds on inflammatory mediators. As for 2 and 5, their analgesic effect may be a result of their activity with the 5-hydroxytryptamine 1A receptor (5-HT1AR) which disrupted the pain-stimulating actions of 5-HT. Antinociceptive activities were documented for various major compounds of the Litsea plants. Overall, the findings suggested Litsea species as good sources of antinociceptive compounds that can be further developed to complement or substitute prescription drugs for pain management.

Synthesis, molecular docking evaluation for LOX and COX-2 inhibition and determination of in-vivo analgesic potentials of aurone derivatives

In the current study, seven (7) aurone derivatives (ADs) were synthesized and employed to in-vitro LOX and COX-2 assays, in-vivo models of acetic acid-induced mice writhing, formalin-induced mice paw licking and tail immersion test to evaluate their analgesic potential at the doses of 10 mg and 20 mg/kg body weight. Molecular docking was performed to know the active binding site at both LOX and COX-2 as compared to standard drugs. Among the ADs, 2-(3,4-dimethoxybenzylidene)benzofuran-3(2H)-one (WE-4)possessed optimal LOX and COX-2 inhibitory strength (IC50=0.30 μM and 0.22 μM) as compared to standard (ZileutonIC50 = 0.08 μM, CelecoxibIC50 = 0.05 μM). Similarly in various pain models compound WE-4 showed significantly (p < 0.05) highest percent analgesic potency as compared to control at a dose of 20 mg/kg i.e. 77.60 % analgesic effect in acetic acid model, 49.97 % (in Phase-1) and 70.93 % (inPhase-2) analgesic effect in formalin pain model and 74.71 % analgesic response in tail immersion model. By the administration of Naloxone, the tail flicking latencies were reversed (antagonized) in all treatments. The WE-4 (at 10 mg/kg and 20 mg/kg) was antagonized after 90 min from 11.23 ± 0.93 and 13.41 ± 1.21 to 5.30 ± 0.48 and 4.80 ± 0.61 respectively as compared to standard Tramadol (from 17.74 ± 1.33 to 3.70 ± 0.48), showing the opiodergic receptor involvement. The molecular docking study of ADs revealed that WE-4 had a higher affinity for LOX and COX-2 with docking scores of -4.324 and -5.843 respectively. As a whole, among the tested ADs, compound WE-4 demonstrated excellent analgesic effects that may have been caused by inhibiting the LOX and COX-2 pathways.

Evaluating The Analgesic Activity of Leaf, Stem Bark Extract And Isolated Nutraceuticals of &lt;i&gt;Caesalpinia Bonducella L (Roxb.)&lt;/i&gt;

Evaluating The Analgesic Activity of Leaf, Stem Bark Extract And Isolated Nutraceuticals of &lt;i&gt;Caesalpinia Bonducella L (Roxb.)&lt;/i&gt;