Antinociceptive and anti-inflammatory effects of Memora nodosa and allantoin in mice

Unveiling the impact of harvest time on Dioscorea opposita Thunb. cv. Tiegun maturity by NMR-based metabolomics and LC-MS/MS analysis

BACKGROUND

Dioscorea opposita Thunb. cv. Tiegun maturity (DM) is an important factor influencing its quality. However, there are few studies on the impact of harvest time on its maturation. In the present study, a NMR-based metabolomics approach was applied to investigate the dynamic metabolic changes of D. opposita Thunb. cv. Tiegun at six different harvest stages: stage 1 (S1), stage 2 (S2), Stage 3 (S3), stage 4 (S4), stage 5 (S5) and stage 6 (S6).

RESULTS

Principal component analysis showed distinct segregation of samples obtained from S1, S2 and S3 compared to those derived from S4, S5 and S6. Interestingly, these samples from the two periods were obtained before and after frost, indicating that frost descent might be important for DM. Eight differential metabolites responsible for good separation of different groups were identified by the principal component analysis loading plot and partial least squares-discriminant analysis. In addition, quantitative analysis of these metabolites using liquid chromatography-tandem mass spectrometry determined the effects of harvest time on these metabolite contents, two of which, sucrose and allantoin, were considered as potential biomarkers to determine DM.

CONCLUSION

The present study demonstrated that NMR-based metabolomics approach could serve as a powerful tool to identify differential metabolites during harvesting processes, also offering a fresh insight into understanding the DM and the potential mechanism of quality formation. © 2024 Society of Chemical Industry.

NIR-Responsive injectable hydrogel cross-linked by homobifunctional PEG for photo-hyperthermia of melanoma, antibacterial wound healing, and preventing post-operative adhesion

Current therapeutic approaches for skin cancer face significant challenges, including wound infection, delayed skin regeneration, and tumor recurrence. To overcome these challenges, an injectable adhesive near-infrared (NIR)-responsive hydrogel with time-dependent enhancement in viscosity is developed for combined melanoma therapy and antibacterial wound healing acceleration. The multifunctional hydrogel is prepared through the chemical crosslinking between poly(methyl vinyl ether-alt-maleic acid) and gelatin, followed by the incorporation of CuO nanosheets and allantoin. The synergistic inherent antibacterial potential of CuO nanosheets, the regenerative and smoothing effect of allantoin, the extracellular matrix-mimicking effect of gelatin, and the desirable swelling behavior of the hydrogel results in fast wound recovery after photothermal ablation of the tumor. Additionally, the hydrogel can serve as an alternative to sutures owing to its tissue adhesiveness ability, which can further render it the merits for accelerated repair of abdominal lesions while acting as a biocompatible barrier to prevent peritoneal adhesion.

A self-healable and bioadhesive acacia gum polysaccharide-based injectable hydrogel for wound healing acceleration

The present study aimed at developing an injectable hydrogel based on acacia gum (AG) for wound healing acceleration. The hydrogels were synthetized through metal-ligand coordination mediated by Fe3+ and characterized in terms of gelation time, gel content, initial water content, swelling capacity, water retention ratio, and porosity. Moreover, FTIR, XRD and TGA analyses were performed for the hydrogels and allantoin (Alla) loaded ones. Furthermore, bioadhessiveness, and self-healing as well as antibacterial, toxicity and wound healing potentials of the hydrogels were evaluated. The hydrogels displayed fast gelation time, high swelling, porosity, and bioadhessiveness, as well as antioxidant, self-healing, antibacterial, blood clotting, and injectability properties. FTIR, XRD and TGA analyses confirmed hydrogel synthesis and drug loading. The Alla-loaded hydrogels accelerated wound healing by decreasing the inflammation and increasing the cell proliferation as well as collagen deposition. Hemocompatibility, cell cytotoxicity, and in vivo toxicity experiments were indicative of a high biocompatibility level for the hydrogels. Given the advantages of fast gelation, injectability and beneficial biological properties, the use of Alla-loaded hydrogels could be considered a new remedy for efficient wound healing.

Characterization and In Vivo Assay of Allantoin-Enriched Pectin Hydrogel for the Treatment of Skin Wounds

This work describes a liquid allantoin-enriched pectin hydrogel with hydrophilic behavior that is supported by the presence of functional groups related to healing efficacy. A topical study shows the effect of the hydrogel application on surgically induced skin wound healing in a rat model. Contact angle measurements confirm hydrophilic behavior (11.37°), while Fourier-transform infrared spectroscopy indicates the presence of functional groups related to the healing effectiveness (carboxylic acid and amine groups). Allantoin is distributed on the surface and inside the amorphous pectin hydrogel surrounded by a heterogeneous distribution of pores. This promotes wound drying with better interaction between the hydrogel and cells involved in the wound healing process. An experimental study with female Wistar rats indicates that the hydrogel improves wound contraction, reducing around 71.43% of the total healing time and reaching total wound closure in 15 days.

Biological Functions of Dillenia pentagyna Roxb. Against Pain, Inflammation, Fever, Diarrhea, and Thrombosis: Evidenced From in vitro, in vivo, and Molecular Docking Study

Dillenia pentagyna Roxb. is traditionally used to treat cancer, wound healing, diabetes, and diarrhea in local tribes. This study was designed to evaluate the pharmacological potentiality of this plant. In vivo analgesic, anti-inflammatory, and antipyretic studies of the methanol extracts of D. pentagyna (MEDP) leaves were performed by using acetic acid-induced nociception, formalin-induced paw licking, and yeast-induced pyrexia assay methods, respectively. In vivo antidiarrheal activity was carried out in mice by following castor oil-induced diarrhea and gastrointestinal transit manner. In vitro thrombolytic experiment was performed employing the clot lysis activity. Besides, a molecular docking study was performed by executing the software (PyRx, Discovery Studio, and UCSF Chimera). In the acetic acid-induced writhing study, MEDP possesses significant writhing inhibition in a dose-dependent manner. It showed 50.86% of maximum inhibition of pain in the case of MEDP at a dose of 400 mg/kg body weight. In the anti-inflammatory study, maximum inhibition rate was observed at a value of 59.98 and 41.29% in early and late phases, respectively, at the dose of 400 mg/kg body weight. In the case of yeast-induced hyperpyrexia, MEDP reduced hyperpyrexia in a dose-dependent manner. In the antidiarrheal assay, MEDP moderately inhibited the occurrence of diarrhea in all the experiments. In the thrombolytic study, a moderate (17.76%) clot lysis potency has been yielded by MEDP. Again, the molecular docking simulation revealed strong binding affinities with almost all the targeted proteins. The present study suggests that the MEDP possesses remarkable pharmacological activity and this finding validated the ethnobotanical significance of D. pentagyna as the source of pain, fever, and diarrhea management agent.

Antinociceptive effects of flower extracts and the active fraction from Styrax japonicus

ETHNOPHARMACOLOGICAL RELEVANCE

Flowers from Styrax japonicus sieb. et Zucc. have been used as a Chinese folk medicine to alleviate pain such as toothache and sore throat.

AIM OF THE STUDY

To testify the analgesic effect of flowers from Styrax japonicus, analyze components of the active fraction, and investigate the mechanism of analgesia.

MATERIALS AND METHODS

Flower extracts were obtained by ethanol, petroleum ether and hydrodistillation extraction. Different fractions of ethanol extracts (EE) were isolated by silica gel column chromatography and preparative liquid chromatography. Analgesic effects of EE, petroleum ether extracts (PEE), hydrodistillation extracts (HDE), and fractions of EE were evaluated using hot plate, acetic acid-induced writhing and formalin tests on mice. Components of the active fraction 1 (F1) were determined by the ultrahigh-performance liquid chromatography Q extractive mass spectrometry (UHPLC-QE-MS). Anti-inflammatory and sedative effects involving analgesic mechanisms were evaluated by carrageenan induced hind paw oedema and pentobarbital sodium sleep tests, respectively. In addition, antagonists including naloxone hydrochloride (NXH), flumazenil (FM), SCH23390 (SCH) and WAY100635 (WAY) were used to investigate the possible mechanism of analgesia. Contents of neurotransmitters and relevant metabolites in different brain regions of mice were also quantified by the ultraperformance liquid chromatography with a fluorescence detector (UPLC-FLD).

RESULTS

EE rather than PEE and HDE at medium and high doses (150 mg/kg and 300 mg/kg) significantly prolonged the latency time of the response of mice to the thermal stimulation in the hot plate test. Moreover, EE significantly decreased number of writhes in the acetic acid-induced writhing test, and reduced licking time in both two phases of the formalin test in a dose-dependent manner. The F1 (50 mg/kg) showed effective antinociceptive responses in all mice models. However, fraction 2 (F2) and fraction 3 (F3) at 50 mg/kg performed no analgesic action. Kaempferol-3-O-rutinoside, isorhamnetin-3-O-rutinoside, pinoresinol-4-O-glucoside, forsythin and arctiin were identified from components of the F1. Furthermore, F1 (50 mg/kg) did not significantly affect hind paw oedema of mice induced by carrageenan but significantly shortened sleep latency and increased sleep duration in the pentobarbital sodium sleep test. In addition, the antinociceptive response of F1 was not affected by NXH in two mice models, but significantly blocked by FM and WAY in the hot plate test. In the formalin test, FM avoided the effect of F1 only in the first phase, while the analgesic activity of F1 was totally suppressed by WAY in both two phases. Otherwise, contents of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) increased significantly in hippocampus and striatum of mice in the F1 group.

CONCLUSION

EE from flowers of Styrax japonicus, and F1, the active part isolated from EE, showed significant antinociceptive activities. The analgesic effect of F1 appeared to be related to the sedative effect, partially mediated by the GABAergic system, and highly involved in the serotonergic system. This was the first study confirming the analgesic effect of Styrax japonicus flower, which provided a candidate for the development of non-opioid analgesics.

Coaxial fibers of poly(styrene-co-maleic anhydride)@poly(vinyl alcohol) for wound dressing applications: Dual and sustained delivery of bioactive agents promoting fibroblast proliferation with reduced cell adherence

The prevalence of chronic and acute wounds, as well as the complexity of their treatment represent a great challenge for health systems around the world. In this context, the development of bioactive wound dressings that release active agents to prevent infections and promote wound healing, appears as the most promising solution. In this work, we develop an antibacterial and biocompatible wound dressing material made from coaxial electrospun fibers of poly(styrene-co-maleic anhydride) and poly(vinyl alcohol) (PSMA@PVA). The coaxial configuration of the fibers consists of a shell of poly (styrene-co-maleic anhydride) containing a variable concentration of silver nanoparticles (AgNPs) 0.1-0.6 wt% as antibacterial agent, and a core of PVA containing 1 wt% allantoin as healing agent. The fibers present diameters between 0.72 and 1.7 µm. The release of Ag⁺ in a physiological medium was studied for 72 h, observing a burst release during the first 14 h and then a sustained and controlled release during the remaining 58 h. Allantoin release curves showed significant release only after 14 h. The meshes showed an antibacterial activity against Pseudomonas aeruginosa and Bacillus subtilis that correlates with the amount of AgNPs incorporated and the release rate of Ag⁺. Indeed, meshes containing 0.3 and 0.6 wt% of AgNPs showed a 99.99% inhibition against both bacteria. The adherence and cell viability of the meshes were evaluated in mouse embryonic fibroblasts NIH/3T3, observing a significant increase in cell viability after 72 h of incubation accompanied by a reduced adhesion of fibroblasts that decreased in the presence of the active agents. These results show that the material prepared here is capable of significantly promoting fibroblast cell proliferation but without strong adherence, which makes it an ideal material for wound dressings with non-adherent characteristics and with potential for wound healing.

Novel 1,3,4-Oxadiazole Derivatives of Pyrrolo[3,4-d]Pyridazinone Exert Anti-Inflammatory Activity without Acute Gastrotoxicity in the Carrageenan-Induced Rat Paw Edema Test

Background and Purpose

Due to the risk of gastrointestinal damage and various tissue toxicity associated with non-steroidal anti-inflammatory drugs (NSAIDs) use, investigating new anti-inflammatory agents with efficacy comparable to that of NSAIDs but reduced toxicity is still a major challenge and a clinical need. Based on our previous study, new 1,3,4-oxadiazole derivatives of pyrrolo[3,4-d]pyridazinone, especially 6-butyl-3,5,7-trimethyl-1-[[4-[[4-(4-nitrophenyl)piperazin-1-yl]methyl]-5-thioxo-1,3,4-oxadiazol-2-yl]methoxy]pyrrolo[3,4-d]pyridazin-4-one and 6-butyl-1-[[4-[[4-(4-chlorophenyl)-4-hydroxy-1-piperidyl]methyl]-2-thioxo-1,3,4-oxadiazol-5-yl]methoxy]-3,5,7-trimethyl-pyrrolo[3,4-d]pyridazin-4-one (hereafter referred to as the compounds 10b and 13b, respectively) seem to be promising anti-inflammatory agents. This study aimed to elucidate the effects of these two new derivatives on the course of experimental rat inflammation, liver and kidney function, and gastric mucosa.

Methods

The anti-inflammatory effect of compounds 10b and 13b was evaluated using the carrageenan-induced paw edema test in rats. The increase in paw volume (paw edema), prostaglandin E₂ (PGE₂), tumor necrosis factor-α (TNF-α) and myeloperoxidase (MPO) levels, histological alterations, and inflammatory cell infiltration in paw tissue were determined. Serum alanine transaminase (ALT) and aspartate transaminase (AST) activities, serum urea and creatinine levels, as well as changes in gastric mucosa, were measured as indicators of hepatic, renal, and gastric toxicity.

Results

Pretreatment with both novel derivatives at 10 mg/kg and 20 mg/kg doses reduced paw edema, counteracted the increased PGE₂ and TNF-α levels, reduced the influx of inflammatory cells, and decreased histopathological alterations in paw tissue. Compound 13b at a dose of 20 mg/kg was more effective than indomethacin in reversing the increased TNF-α levels and reducing the influx of inflammatory cells. Only compound 13b at all studied doses (5, 10, or 20 mg/kg) counteracted the increased MPO level in paw tissue. Both compounds neither caused alterations in ALT, AST, urea, creatinine parameters nor gastric mucosal lesions.

Conclusion

New compounds exert an anti-inflammatory effect, presumably via inhibiting inflammatory mediators release and inflammatory cell infiltration. Moreover, both possess a more favorable benefit–risk profile than indomethacin, especially compound 13b.

Allantoin, a purine metabolite, enhances peripheral nerve regeneration following sciatic nerve injury in rats: A stereological and immunohistochemical study

AIM

Following peripheral nerve injury, in addition to axonal and myelin degeneration, a sharp increase is observed in cell numbers, especially Schwann cells, in the distal part of the injury. This study investigated the effect of allantoin, involved in purine catabolism, on the reactions occurring in the lesion area.

MATERIAL AND METHOD

An experimental sciatic nerve injury model was established with the application of pressure at 50 Newtons for 5 s to the right sciatic nerves of experimental animals following visualization with the help of pliers. Allantoin was administered to the test groups via the intraperitoneal (i.p.) route (10 mg/kg), at the same time every day for 30 days. The animals were sacrificed at the end of 30 days, following electromyography and Sciatic Function Index tests. Myelinated/unmyelinated axon numbers were evaluated stereologically. Myelin sheath thickness, axon diameter, mitotic activity, and functional improvement in muscles in this peripheral nerve degeneration model were investigated. The test results were then subjected to statistical analysis.

RESULTS

Allantoin was observed to exhibit curative effects in terms of function, although stereological tests revealed no morphological differences.

CONCLUSION

The i.p. administration of allantoin may have a beneficial effect on nerve healing.

Antinociceptive and Anti-Inflammatory Effects of Saline Extract and Lectin-Rich Fraction from Microgramma vacciniifolia Rhizome in Mice

Previous studies have characterized a saline extract from Microgramma vacciniifolia rhizome and its lectin (MvRL)-rich fraction with low acute toxicity. In the present study, we evaluated these preparations for acute toxicity (1,000 mg/kg) and antinociceptive and anti-inflammatory activities (100-400 mg/kg for the extract and 25-50 mg/kg for the fraction). No signs of toxicity were observed. Both the extract and fraction increased the latency period for nociception in the hot plate assay, decreased writhing induced by acetic acid, and promoted analgesic effects in phases 1 and 2 of the formalin test. The antinociceptive mechanism was attributed to interactions with opioid receptors and K⁺ ATPase channels. The extract and fraction decreased carrageenan-induced paw edema in 46.15 % and 77.22 %, respectively, at the highest doses evaluated. Furthermore, the fraction was shown to act on the bradykinin pathway. The ability to decrease leukocyte migration after treatment was also verified in the peritonitis and air pouch models. In exudates collected from air pouches, decreased tumor necrosis factor (TNF)-α and increased interleukin (IL)-10 levels were noted. Both the extract and fraction also effectively inhibited the development of granulomatous tissue. In conclusion, the substances investigated in this study can be used for the development of novel therapeutic options for pain and inflammatory processes.

Botanical formulation, TADIOS, alleviates lipopolysaccharide (LPS)-Induced acute lung injury in mice via modulation of the Nrf2-HO-1 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

TADIOS is an herbal formulation prepared from a mixture of Taraxacum officinale (L.) Weber ex F.H.Wigg, Dioscorea batatas Decaisne and Schizonepeta tenuifolia (Benth.) Briquet. These plants have traditionally been used in Asia to treat a variety of respiratory diseases. A bulk of literature on traditional Korean medicine describe their activities and functions for respiratory problems. Therefore, we hypothesized that the combination of these plants might be effective in alleviating respiratory symptoms.

AIM OF THE STUDY

In this study, we investigated whether TADIOS ameliorates LPS-induced acute lung injury via regulation of the Nrf2-HO-1 signaling pathway.

MATERIALS AND METHODS

The LPS-induced acute lung injury mouse model was used to determine the anti-inflammatory and anti-oxidative stress effects of TADIOS. The amount of marker compounds contained in TADIOS was quantified using high-performance liquid chromatography (HPLC) analysis. The protein level of pro-inflammatory cytokines in culture supernatant was measured by ELISA. Changes in the RNA level of pro-inflammatory cytokines in mice lungs and RAW264.7 cells were measured by quantitative RT-PCR. The relative amounts of reactive oxygen species (ROS) were measured by DCF-DA assay. Western blot analysis was used to evaluate expression of cellular proteins. Effects of TADIOS on antioxidant responsive elements (AREs) were determined by luciferase assay. The severity of acute lung injury was evaluated by Hematoxylin & Eosin (H&E) staining. To test the effects of TADIOS on LPS-induced oxidative stress, myeloperoxidase (MPO) activity and the total antioxidant capacity were measured.

RESULTS

TADIOS was prepared by extraction of a blend of these three plants by ethanol, and quality control was performed through quantification of marker compounds by HPLC and measurement of bioactivities using cell-based bioassays. In the murine macrophage cell line RAW264.7, TADIOS effectively suppressed the production of pro-inflammatory cytokines such as IL-6 and IL-1β, and also ROS induced by LPS. When RAW264.7 cells were transfected with a luciferase reporter plasmid containing nucleotide sequences for AREs, TADIOS treatment increased the level of relative luciferase units in a dose-dependent manner. In the LPS-induced acute lung injury mouse model, orally administered TADIOS alleviated lung damage and neutrophil infiltration induced by LPS. Consistent with the in vitro data, treatment with TADIOS inhibited the LPS-mediated expression of pro-inflammatory cytokines and oxidative stress, and activated the Nrf2-HO-1 axis.

CONCLUSION

Our data suggest the potential for TADIOS to be developed as a safe and effective therapeutics for the treatment of acute respiratory distress syndrome.

Ellagitannins from Rosa roxburghii suppress poly(I:C)-induced IL-8 production in human keratinocytes

The anti-inflammatory effects of a 50% aqueous extract of Rosa roxburghii fruit (RRFE) and two ellagitannins (strictinin and casuarictin) isolated from the RRFE were evaluated in a cell model of skin inflammation induced by self-RNA released from epidermal cells damaged by UV ray (UVR) irradiation. The RRFE inhibited interleukin-8 (IL-8) mRNA expression in normal human epidermal keratinocytes (NHEKs) stimulated with polyinosinic:polycytidylic acid (poly(I:C)), a ligand of toll-like receptor-3 (TLR-3). The plant-derived anti-inflammatory agents, dipotassium glycyrrhizinate (GK2) and allantoin, had no influence on the IL-8 expression. The purified compounds, strictinin and casuarictin, inhibited the IL-8 mRNA expression and IL-8 release induced in NHEKs by poly(I:C). These ellagitannins were thus found to be responsible for the biological activity exhibited by the RRFE. This study demonstrates that RRFE and isolated RRFE compounds show promise as ingredients for products formulated to improve skin disorders induced by UVR irradiation.

Antiphotoaging Potential of Extracts of Yin-Tonic Herbal Medicine in Skin Cell and Human Skin Equivalent

Yin-tonic herbal medicines have been shown to possess properties that make skin healthy by nourishing within various organs of the body. However, the antiphotoaging effect of these medicines on the skin has not been fully studied. Photoaging occurs with prolonged sun exposure and causes skin damage and aging, with depletion of the dermal extracellular matrix and chronic alterations in skin structure, such as wrinkles. In this study, we assessed the antiphotoaging effects of eight yin-tonic herbal medicines on human skin cells and skin equivalents. The levels of type I procollagen and matrix metalloproteinase-1 (MMP-1) in ultraviolet B- (UVB-) irradiated CCD-986sk fibroblasts were measured, and then three medicines were chosen based on screening results. Using UVB-irradiated human skin equivalents, we evaluated the effect of three yin-tonic herbal medicines on histological changes of skin, epidermal and dermal thickness, and MMP-1 production. Furthermore, we observed collagen fiber content and protein expression of filaggrin in UVB-irradiated human skin equivalents. Yin-tonic herbal medicines increased type I procollagen levels and decreased the production of MMP-1 in UVB-irradiated CCD-986sk fibroblasts. The three selected yin-tonic herbal medicines recovered the collagen content and filaggrin expression via MMP-1 downregulation in UVB-irradiated human skin equivalents. Our results show that yin-tonic herbal medicines can prevent skin photoaging by reduction of MMP-1 levels and increasing the expression of moisturizing factors. Based on these results, we suggest that yin-tonic herbal medicines have the potential to be used as helpful agent for skin photoaging.

Formulation, optimization and characterization of allantoin-loaded chitosan nanoparticles to alleviate ethanol-induced gastric ulcer: in-vitro and in-vivo studies

Allantoin (ALL) is a phytochemical possessing an impressive array of biological activities. Nonetheless, developing a nanostructured delivery system targeted to augment the gastric antiulcerogenic activity of ALL has not been so far investigated. Consequently, in this survey, ALL-loaded chitosan/sodium tripolyphosphate nanoparticles (ALL-loaded CS/STPP NPs) were prepared by ionotropic gelation technique and thoroughly characterized. A full 24 factorial design was adopted using four independently controlled parameters (ICPs). Comprehensive characterization, in vitro evaluations as well as antiulcerogenic activity study against ethanol-induced gastric ulcer in rats of the optimized NPs formula were conducted. The optimized NPs formula, (CS (1.5% w/v), STPP (0.3% w/v), CS:STPP volume ratio (5:1), ALL amount (13 mg)), was the most convenient one with drug content of 6.26 mg, drug entrapment efficiency % of 48.12%, particle size of 508.3 nm, polydispersity index 0.29 and ζ-potential of + 35.70 mV. It displayed a sustained in vitro release profile and mucoadhesive strength of 45.55%. ALL-loaded CS/STPP NPs (F-9) provoked remarkable antiulcerogenic activity against ethanol-induced gastric ulceration in rats, which was accentuated by histopathological, immunohistochemical (IHC) and biochemical studies. In conclusion, the prepared ALL-loaded CS/STPP NPs could be presented to the phytomedicine field as an auspicious oral delivery system for gastric ulceration management.

Novel 1,3,4-Oxadiazole Derivatives of Pyrrolo[3,4-d]pyridazinone Exert Antinociceptive Activity in the Tail-Flick and Formalin Test in Rodents and Reveal Reduced Gastrotoxicity

Despite the availability of the current drug arsenal for pain management, there is still a clinical need to identify new, more effective, and safer analgesics. Based on our earlier study, newly synthesized 1,3,4-oxadiazole derivatives of pyrrolo[3,4-d]pyridazinone, especially 10b and 13b, seem to be promising as potential analgesics. The current study was designed to investigate whether novel derivatives attenuate nociceptive response in animals subjected to thermal or chemical noxious stimulus, and to compare this effect to reference drugs. The antinociceptive effect of novel compounds was studied using the tail-flick and formalin test. Pretreatment with novel compounds at all studied doses increased the latency time in the tail-flick test and decreased the licking time during the early phase of the formalin test. New derivatives given at the medium and high doses also reduced the late phase of the formalin test. The achieved results indicate that new derivatives dose-dependently attenuate nociceptive response in both models of pain and exert a lack of gastrotoxicity. Both studied compounds act more efficiently than indomethacin, but not morphine. Compound 13b at the high dose exerts the greatest antinociceptive effect. It may be due to the reduction of nociceptor sensitization via prostaglandin E₂ and myeloperoxidase levels decrease.

The leaves of Bougainvillea spectabilis suppressed inflammation and nociception in vivo through the modulation of glutamatergic, cGMP, and ATP-sensitive K+ channel pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Bougainvillea spectabilis is an ornamental shrub from Nyctaginaceae family, widely used in the traditional medicine in the treatment of pain, inflammation, and ulcer. Some research investigated the analgesic potential of this plant, however, the in-depth analysis of its antinociceptive properties and molecular mechanism(s) are yet to be revealed.

PURPOSE OF THE STUDY

This study, therefore, investigated the antinociceptive potential of methanol extract of the leaves of B. spectabilis (MEBS) with possible molecular mechanism(s) of action using several pre-clinical models of acute and chronic pain in mice.

MATERIALS AND METHODS

The dry leaf powder of B. spectabilis was macerated with 100% methanol, and then dried crude extract was used for in vivo experiments. Following the acute toxicity test with 500, 1000, and 2000 mg/kg b.w. doses of MEBS, the central antinociceptive activities of the extract (50, 100, and 200 mg/kg b.w.) were evaluated using hot plate and tail immersion tests, whereas the peripheral activities were investigated using acetic acid-induced writhing, formalin-induced licking and oedema, and glutamate-induced licking tests. Moreover, the possible involvements of cGMP and ATP-sensitive K+ channel pathways in the observed antinociceptive activities were also investigated using methylene blue (20 mg/kg b.w.) and glibenclamide (10 mg/kg b.w.), respectively. We also performed GC/MS-MS analysis of MEBS to identify the phyto-constituents and in silico modelling of the major compounds for potential molecular targets.

RESULTS

Our results demonstrated that MEBS at 50, 100, and 200 mg/kg b.w. doses were not effective enough to suppress centrally mediated pain in the hot plate and tail immersion models. However, the extract was potent (at 100 and 200 mg/kg b.w. doses) in reducing peripheral nociception in the acetic acid-induced writhing and inflammatory phase of the formalin tests. Further analyses revealed that MEBS could interfere with glutamatergic system, cGMP and ATP-sensitive K⁺ channel pathways to show its antinociceptive properties. GC/MS-MS analysis revealed 35 different phytochemicals with potent anti-inflammatory and antinociceptive properties including phytol, neophytadiene, 2,4-Di-tert-butylphenol, fucoxanthin, and Vit-E. Prediction analysis showed high intestinal absorptivity and low toxicity profiles of these compounds with capability to interact with glutamatergic system, inhibit JAK/STAT pathway, scavenge nitric oxide and oxygen radicals, and inhibit expression of COX3, tumor necrosis factor, and histamine.

CONCLUSION

Taken together, these results suggested the antinociceptive potentials of MEBS which were mediated through the modulation of glutamatergic, cGMP, and ATP-sensitive K⁺ channel pathways. These also suggested that MEBS could be beneficial in the treatment of complications associated with nociceptive pain.

Antinociceptive activity of Schinus terebinthifolia leaf lectin (SteLL) in sarcoma 180-bearing mice

ETHNOPHARMACOLOGY RELEVANCE

Schinus terebinthifolia Raddi leaves have been used in folk medicine due to several properties, including antitumor and analgesic effects. The variable efficacy and adverse effects of analgesic drugs have motivated the search for novel antinociceptive agents. It has been reported that the S. terebinthifolia leaf lectin (SteLL) has antitumor activity against sarcoma 180 in mice.

AIM OF THE STUDY

This work aimed to evaluate whether SteLL would reduce cancer pain using an orthotopic tumor model.

MATERIALS AND METHODS

A sarcoma 180 cell suspension was inoculated into the right hind paws of mice, and the treatments (150 mM NaCl, negative control; 10 mg/kg morphine, positive control; or SteLL at 1 and 2 mg/kg) were administered intraperitoneally 24 h after cell inoculation up to 14 days. Spontaneous nociception, mechanical hyperalgesia, and hot-plate tests were performed. Further, the volume and weight of the tumor-bearing paws were measured.

RESULTS

SteLL (2 mg/kg) improved limb use during ambulation. The lectin (1 and 2 mg/kg) also inhibited mechanical hyperalgesia and increased the latency time during the hot-plate test. Naloxone was found to reverse this effect, indicating the involvement of opioid receptors. The tumor-bearing paws of mice treated with SteLL exhibited lower volume and weight.

CONCLUSION

SteLL reduced hyperalgesia due to sarcoma 180 in the paws of mice, and this effect can be related to its antitumor action.

Machaerium hirtum (Vell.) Stellfeld Alleviates Acute Pain and Inflammation: Potential Mechanisms of Action

Machaerium hirtum (Vell.) Stellfeld (Fabaceae) known in Brazil as “jacaranda de espinho” or “espinheira santa nativa” is a medicinal plant commonly used in folk medicine to treat ulcers, cough and diarrhea. This study aimed to investigate the anti-inflammatory and antinociceptive effects of hydroalcoholic extracts from M. hirtum twig (HEMh) using in vivo experimental models of nociception through the involvement of transient receptor potential channels, acid-sensing ion channel (ASIC), nitrergic, opioidergic, glutamatergic, and supraspinal pathways. Our results revealed an antinociceptive effect of HEMh mediated by the opioidergic, l-arginine-nitric oxide and glutamate systems, as well as by interactions with TRPA1/ASIC channels. The anti-inflammatory effect of HEMh evaluated with a xylene-induced ear edema and by the involvement of arachidonic acid and prostaglandin E2 (PGE₂) showed involvement of the COX pathway, based on observed decreases in PGE₂ levels. A phytochemical investigation of the HEMh led to the isolation of α-amyrin, β-amyrin, allantoin, apigenin-7-methoxy-6-C-β-d-glucopyranoside, and apigenin-6-C-β-d-glucopyranosyl-8-C-β-d-xylopyranoside. In conclusion, the acute oral administration of HEMh inhibits the nociceptive behavioral response in animals through the nitrergic, opioid, glutamatergic pathways, and by inhibition of the TRPA1 and ASIC channels, without causing locomotor dysfunction. In addition, its anti-inflammatory effect is associated with the COX pathway and decreased PGE₂ levels.

A mechanistic approach to HPLC analysis, antinociceptive, anti-inflammatory and postoperative analgesic activities of panch phoron in mice

Background

Panch phoron is a mixture of five spices containing an equal proportion of Foeniculum vulgare (fennel), Trigonella foenum-graecum Linn (fenugreek), Nigella sativa (black cumin), Cuminum cyminum (cumin) and Brassica nigra (black mustard). The mixture is commonly used in Bangladeshi cuisine and possesses many pharmacological effects. In this study, we evaluated the antinociceptive and anti-inflammatory activities of aqueous panch phoron extract (PPE) in vivo, its possible mechanism of action and phytochemical analysis by High-Performance Liquid Chromatography (HPLC). We also investigated the effect of PPE on postoperative pain in mice.

Methods

HPLC was carried out using LC-20A Modular HPLC system to identify the bioactive compounds present in PPE. Five groups of Swiss albino male mice (n = 6 per group) were orally treated with 10 ml/kg of distilled water or 10 mg/kg of sodium diclofenac or three doses of PPE (100 mg/kg, 300 mg/kg, 500 mg/kg). In vivo assessment was carried out by the writhing test, tail-flick test, formalin test, and carrageenan induced paw edema test. The opioid antagonist, naloxone was used in the acetic acid test to evaluate the involvement of opioid receptors. To assess the effect of PPE in postoperative pain, mice that underwent sciatic nerve surgery were measured for the paw withdrawal latency in a hot water bath.

Results

In HPLC analysis, different types of phenolic compounds and flavonoids, including catechin hydrate, para-coumaric acid, vanillic acid, and syringic acid were detected. Treatment with PPE exhibited dose-dependent antinociceptive and anti-inflammatory activities in pain models (p < 0.05). Furthermore, naloxone did not reverse the effect of PPE in the writhing test. Mice that underwent sciatic nerve surgery showed that the paw withdrawal latency increased gradually over 7 days.

Conclusions

Our results demonstrate that PPE has significant antinociceptive and anti-inflammatory activities and can provide significant postoperative analgesia.

Antinociceptive and antioxidant effects of extract enriched with active indole alkaloids from leaves of Tabernaemontana catharinensis A. DC

ETHNOPHARMACOLOGICAL RELEVANCE

Ethnopharmacological knowledge is important for the identification of active compounds from natural products. Pain may have different aetiologies with complex mechanisms. Tabernaemontana catharinensis A. DC. is well known for indole alkaloids, being used empirically in folk medicine, with antimicrobial and anti-inflammatory as well as antiofidic actions among others.

AIM OF THE STUDY

This work aims to evaluate the antinociceptive and antioxidant effect in mice of the alkaloids extract from leaves of Tabernaemontana catharinensis A. DC. (AITc).

MATERIALS AND METHODS

The AITc was produced by ultrasound and acid-base extraction, and the chemical composition was evaluated by high resolution mass spectrometry. Male mice (Mus musculus), Swiss, were used for in vivo tests. The AITc was administrated at doses of 1.0, 5.0, and 10.0 mg/kg in acetic acid model, formalin, tail-immersion, hot plate, and open field tests, and compared to saline, morphine, or diazepam controls, depending on the test. The toxicological, biochemical, haemogram and antioxidant effect were evaluated in mouse organs such as liver, brain, kidneys, spleen and stomach.

RESULTS

In total, 10 compounds were identified in the AITc, being from the indole alkaloids from the ibogan and corynanthean classes. The extract in doses ranging from 5.0 to 10.0 mg/kg showed an antinociceptive effect for acetic acid, inhibiting by 47.7% and 61.6%. In the same line, reductions of 47.1% (first phase) and 43.6% (second phase) were observed for the 5.0 mg/kg dose in the formalin test. However, tail-immersion and hot plate tests did not show considerable modifications in the latency period, while in the open field test there was an inhibition of only 5.1%. It was observed no differences in NO levels and total antioxidant status of the mice in any of the studie tissues.

CONCLUSIONS

The results justify the use of this plant in traditional medicine. in vivo tests indicate that these compounds possess central and peripheral mechanisms of action. This is study that reports the nociceptive action of these alkaloids, also including toxicity tests, which are intended to guarantee the safety of use of extracts of this plant.

Allantoin attenuates deficits of behavioural and motor nerve conduction in an animal model of cisplatin-induced neurotoxicity in rats

BACKGROUND

The aim of the present study was to evaluate the neuroprotective effect of allantoin in cisplatin-induced toxicity in rats.

METHODS

Adult male Wistar rats weighing 160-200 g were used. Neuropathy was induced by injecting cisplatin (2 mg/kg, ip, twice a week for 6 weeks) and the rats were concurrently treated with allantoin (200 and 400 mg/kg, po) for 8 weeks. At the end of the study, body weight and hemogram were measured. Behavioural tests were performed, including tests for cold and hot hyperalgesia, motor co-ordination, locomotor activity, mechano-tactile allodynia and mechanical hyperalgesia. The rats were then sacrificed and sciatic nerve conduction velocity was determined. The antioxidant enzyme and nitric oxide levels in sciatic nerve homogenates were measured.

RESULTS

In this study, allantoin restored the motor nerve conduction velocity deficits induced by cisplatin, and the allantoin-treated rats showed improvement in cold and thermal hyperalgesia, mechano-tactile allodynia, and mechanical hyperalgesia. Allantoin treatment also improved the rats' hematological status, increasing haemoglobin, platelet and RBC counts compared to the cisplatin-treated group. Allantoin treatment also mitigated the functional abnormalities seen in the cisplatin neuropathy group, protecting neurons from the neurotoxic effects of cisplatin.

CONCLUSION

Allantoin shows promise for use as an adjuvant drug in cancer treatment to protect against cisplatin-induced neuropathy.

Allantoin improves histopathological evaluations in a rat model of gastritis

PURPOSE

Gastritis is found to be one of the most common gastrointestinal diseases worldwide. However, current therapeutic agents cause side effects, interaction, and recurrence. Allantoin has anti-inflammatory and wound healing properties. In this study, the therapeutic effect of allantoin has been assessed on the histopathological indices and gastric mucosal barrier of male rats.

METHODS

Male rats were equally divided into control, ethanol-induced gastritis, and allantoin groups. The therapeutic groups consisted of gastritis plus 12.5 mg/kg allantoin, gastritis plus 25 mg/kg allantoin, and gastritis plus 50 mg/kg allantoin groups. After 5 days of allantoin administration, the rats were sacrificed and a part of their gastric tissue was maintained at -70 °C for prostaglandin E2 (PGE2) and non-protein sulfhydryl (NP-SH) measurements. Another part was stained with hematoxylin and eosin and Masson's trichrome.

RESULTS

We found that Allantoin increased parietal and mucosal cell counts and mucosal thickness after gastritis induction. In addition, the number of leukocytes and vessels decreased in both of the mucosal and the submucosal layers. Allatoin improved gastric ulcer in all treatment groups. Gastric levels of PGE2 and NP-SH increased after allantoin treatment.

CONCLUSION

This study indicated that allantoin had a considerable effect on gastritis treatment, which seems to result from the reinforcement of gastric mucosal barrier.

Effects of Herbal Formulas Bojungikgi-tang and Palmijihwang-hwan on Inflammation in RAW 264.7 Cells and the Activities of Drug-Metabolizing Enzymes in Human Hepatic Microsomes

In the present study, Bojungikgi-tang (BJIKT: Buzhongyiqi-tang, Hochuekki-to) and Palmijihwang-hwan (PMJHH: Baweidìhuang-wan, Hachimijio-gan), traditional herbal formulas, investigated anti-inflammatory efficacies in murine macrophage cell line and the influence on the activities of drug-metabolizing enzymes (DMEs). The anti-inflammatory potentials of the herbal formulas were evaluated to inhibit the production of the inflammatory mediators and cytokines and the protein expression of inducible nitric oxide and cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-treated RAW 264.7 cells. The activities of the major human DMEs, cytochrome P450 isozymes (CYP450s) and UDP-glucuronosyltransferase isozymes (UGTs), were measured by in vitro enzyme assay systems. BJIKT and PMJHH significantly suppressed the prostaglandin E₂ (PGE₂) production (IC₅₀ = 317.3 and 282.2 μg/mL, respectively) and the protein expression of COX-2 in LPS-treated RAW264.7 cells. On the human microsomal DMEs, BJIKT inhibited the activities of CYP1A2 (IC₅₀ = 535.05 μg/mL), CYP2B6 (IC₅₀ > 1000 μg/mL), CYP2C9 (IC₅₀ = 800.78 μg/mL), CYP2C19 (IC₅₀ = 563.11 μg/mL), CYP2D6 (IC₅₀ > 1000 μg/mL), CYP2E1 (IC₅₀ > 1000 μg/mL), CYP3A4 (IC₅₀ = 879.60 μg/mL), UGT1A1 (IC₅₀ > 1000 μg/mL), and UGT1A4 (IC₅₀ > 1000 μg/mL), but it showed no inhibition of the UGT2B7 activity at doses less than 1000 μg/mL. PMJHH inhibited the CYP2D6 activity (IC₅₀ = 280.89 μg/mL), but IC₅₀ values of PMJHH exceeded 1000 μg/mL on the activities of CYP1A2, CYP2C19, CYP2E1, and CYP3A4. At concentrations less than 1000 μg/mL, PMJHH did not affect the activities of CYP2B6, CYP2C9, UGT1A1, UGT1A4, and UGT2B7. The results indicate that both BJIKT and PMJHH may be potential candidates to prevent and treat PGE₂- and COX-2-mediated inflammatory diseases. In addition, this study will expand current knowledge about herb-drug interactions by BJIKT and PMJHH.

Antinociceptive and anti-edema properties of the ethyl acetate fraction obtained from extracts of Coriandrum sativum Linn. leaves

This study evaluated the antinociceptive and anti-edema properties of fractions of Coriandrum sativum Linn. (Apiaceae/Umbelliferae) leaves in mice. Ethyl acetate fractions (FAc) were obtained from dichloromethane extracts prepared from dried C. sativum (CS) leaves and stems. The effects of different concentrations of FAc on mice were observed using the open-field test, formalin-, capsaicin-, and carrageenan-induced paw edema tests, and the acetic acid-induced abdominal writhing test. Results from the carrageenan-induced paw edema test were subjected to a linear regression analysis and data from other assays were subjected to the Kruskal-Wallis test (followed by the SNK post hoc test). Dihydrocoriandrin (34.5%), coriandrin (14.4%), vitamin E (4.6%), and stigmasterol (7.9%) were identified in FAc. The number of squares the mice crossed in the open field test was decreased by 100 mg/kg and 300 mg/kg FAc (i.p.). The administration of 30, 100, and 300 mg/kg FAc induced fewer abdominal writhes than the control. In the formalin test, neurogenic pain was reduced by 20 mg/kg morphine and 30 and 100 mg/kg FAc, but not 5 mg/kg dexamethasone or 10 mg/kg FAc. Formalin-induced inflammatory pain was decreased by morphine, dexamethasone, and 30 and 100 mg/kg FAc. Morphine and 30, 100, and 300 mg/kg FAc significantly decreased the reaction time during the capsaicin test. Dexamethasone reduced both early and later phases of carrageenan-induced edema. Both 30 and 300 mg/kg FAc induced less edema than the control throughout the experiment. FAc showed antinociceptive, anti-edema and anti-inflammatory properties and it may be considered as a potential phytotherapeutic agent in the future.

Analgesic effects of Marasmius androsaceus mycelia ethanol extract and possible mechanisms in mice

Marasmius androsaceus is a medicinal fungus mainly used to treat various forms of pain in China. This study investigated the analgesic effects of an ethanol extract of M. androsaceus (MAE) and its potential molecular mechanisms. Oral administration of MAE (50, 200, and 1000 mg/kg) had significant analgesic effects in an acid-induced writhing test, a formalin test, and a hot-plate test, with effectiveness similar to tramadol (the positive control drug). The autonomic activity test showed that MAE had no harmful effects on the central nervous system in mice. MAE resulted in significantly enhanced levels of noradrenalin and 5-hydroxytryptamine in serum but suppressed both of these neurotransmitters in the hypothalamus after 30 s of hot-plate stimulation. Co-administration with nimodipine (10 mg/kg; a Ca²⁺ channel blocker) strongly enhanced the analgesic effect in the hot-plate test compared to MAE alone. Moreover, MAE down-regulated the expression of calmodulin-dependent protein kinase II (CaMKII) in the hypothalamus after a 30-s thermal stimulus. These results suggested that the analgesic ability of MAE is related to the regulation of metabolism by monoamine neurotransmitters and Ca²⁺/CaMKII-mediated signaling, which can potentially aid the development of peripheral neuropathic pain treatments obtained from M. androsaceus.

An integrated metabolomic strategy for the characterization of the effects of Chinese yam and its three active components on septic cardiomyopathy

This integrated metabolomic approach interpreted the effects of Chinese yam on septic cardiomyopathy and the roles of its major active components.

Anti-inflammatory and Analgesic Effects of Polygonum orientale L. Extracts

Background and Purpose:Polygonum orientale L. (family: Polygonaceae), named Hongcao in China, is a Traditional Chinese Medicinal and has long been used for rheumatic arthralgia and rheumatoid arthritis. However, no pharmacological and mechanism study to confirm these clinic effects have been published. In this investigation, the anti-inflammatory, analgesic effects and representative active ingredient compounds of P. orientale have been studied. Methods: Dried small pieces of the stems and leaves of P. orientale were decocted with water and partitioned successively to obtain ethyl acetate and ethyl ether extract of P. orientale (POEa and POEe). Chemical compositions of them were analyzed by UPLC-Q-Exactive HRMS. Anti-inflammatory and analgesic effects of POEa and POEe were evaluated using xylene induced ear edema, carrageenan induced paw edema, Freunds' complete adjuvant induced arthritis, and formaldehyde induced pain in rat. Their mechanisms of anti-inflammatory and analgesic effects were also studied via assays of TNF-α, IL-1β, IL-6, and PGE2 in serum. Results: UPLC-Q-Exactive HRMS analysis showed that POEa and POEe mainly contained flavonoids including orientin, isoorientin, vitexin, luteolin, and quercetin. Furthermore, anti-inflammatory effects of POEa and POEe were evident in xylene induced ear edema. The paw edema in Freund's complete adjuvant and carrageenan were significantly (P < 0.05, 0.01) inhibited by POEa (5, 7.5 g/kg). POEe (7.5 g/kg) was significantly (P < 0.05, 0.01) inhibited Freunds' complete adjuvant induced paw edema and cotton pellet induced granuloma formation. Similarly, POEe significantly (P < 0.05, 0.01) inhibited the pain sensation in acetic acid induced writhing test. POEa (5, 7.5 g/kg) significantly (P < 0.05, 0.01) inhibited formaldehyde induced pain in both phases. POEa (7.5 g/kg) markedly (P < 0.05) prolonged the latency period of hot plate test after 30 and 60 min. The concentrations of TNF-α, IL-1β, IL-6, and PGE2 were significantly (P < 0.01) decreased by POEa (3.75, 5 g/kg). Conclusion: POEa and POEe have anti-inflammatory and analgesic effects, which was mainly relevant to the presence of flavonoids, including orientin, isoorientin, vitexin, luteolin, and quercetin. The mechanism of anti-inflammatory and analgesic effects of POEa may be to decrease the concentrations of TNF-α, IL-1β, IL-6, and PGE2 in serum.

Evidence of anti-inflammatory and antinociceptive activities of Plinia edulis leaf infusion

ETHNOPHARMACOLOGICAL RELEVANCE

Plinia edulis (Vell.) Sobral (Myrtaceae) is native and endemic to the Brazilian Atlantic Rainforest. Popularly known as "cambucá", it has been used in folk medicine for the treatment of stomach disorders, diabetes, bronchitis, inflammation and as tonic. Although there are numerous records concerning its popular use as analgesic and anti-inflammatory, scientific information regarding these pharmacological activities is limited. Therefore, the aim of this study was to characterize the anti-inflammatory and antinociceptive activity of P. edulis leaf infusion (AEPe) in mice.

MATERIALS AND METHODS

The acetic acid-induced writhing response and mechanical nociceptive paw tests were used to evaluate the antinociceptive activity. Carrageenan-induced paw edema and lipopolysaccharide-induced peritonitis were used to investigate the anti-inflammatory activity. The substances in AEPe were identified by HPLC-MS analysis.

RESULTS

At the test doses 30-300mg/kg p.o., AEPe has clearly exhibited anti-inflammatory effects, reducing carrageenan-induced paw edema and inhibiting leukocyte recruitment into the peritoneal cavity. The infusion has shown significant antinociceptive activity in both models of nociception. Gallic acid, myricitrin, guaijaverin, quercitrin, quercetin, corosolic acid, maslinic acid, oleanolic acid and ursolic acid were identified in AEPe.

CONCLUSION

P. edulis infusion presented antinociceptive and anti-inflammatory activities in all experiments realized in this study, which could be related to the presence of triterpenoids and flavonoids. These results provide scientific support for the traditional use of this species in the management of pain and inflammation.

The gastroprotective effect of Memora nodosa roots against experimental gastric ulcer in mice

ABSTRACT Memora nodosa is popularly known as "caroba" and widely found in the Cerrado regions of Brazil. In traditional medicine, the leaves and stems are used for the healing of external ulcer and the roots for abdominal pain. This study investigated the effect of ethanolic roots extract of Memora nodosa (EMN) on the gastric mucosa of mice. In the indomethacin induced gastric ulcer model, the treatments of the animals with EMN at doses of 100, 300 and 1000 mg/kg, p.o., markedly reduced the index of lesions. In the gastric ulcer models induced by ethanol and cold restraint-stress the previous treatment with EMN at dose of 300 mg/kg showed 69% and 43% of protection, respectively. Seven days after food-restriction, the animals treated with EMN (300 mg/kg p.o.) showed reduction in the index of lesion by 65% as compared to control group. The intraduodenal administration of EMN (300 mg/kg) did not alter the gastric acid secretion parameters. The treatment with EMN (300 mg/kg p.o.) did not alter glutathione levels (GSH), but showed an increase of adhered gastric mucus as compared to the control group with lesion. These results showed that EMN has gastroprotective activity probably due with an increase of adhered gastric mucus.