Distribution and regulation of cyclooxygenase-2 in carrageenan-induced inflammation

Effect of gamma-terpinene on the articular inflammatory response

This study investigates the anti-inflammatory and antinociceptive effects of gamma-terpinene (GT), a monoterpene present in essential oils, in models of acute joint inflammation and pain. GT was administered orally at doses of 25, 50, 75, and 100 mg/kg. Joint inflammation was induced by an intra-articular injection of zymosan to assess joint edema, leukocyte migration, and myeloperoxidase (MPO) enzyme activity. A carrageenan-induced paw edema model was used to evaluate edema and mechanical hyperalgesia, with measurements taken via plethysmometry and Von Frey testing. Results showed that GT significantly decreased leukocyte migration, joint edema, and MPO activity in the zymosan model, indicating an anti-inflammatory effect. In the carrageenan model, GT also demonstrated a dose-dependent reduction in paw edema and mechanical hyperalgesia, highlighting its analgesic potential. These findings support that GT possesses notable anti-inflammatory and antinociceptive properties, making it a promising candidate for natural therapeutic applications in managing inflammatory joint conditions. This suggests a potential role of GT as a natural alternative to NSAIDs and glucocorticoids (GCs), reducing inflammation while minimizing side effects. Future studies should explore its clinical applicability and long-term safety.

Assessment of binding affinity of major bioactive compounds from Momordica charantia, Azadirachta indica, Nelumbo nucifera, Caesalpinia crista, Martynia annua and Erythrina variegate to COX-2 receptor: an in silico study

In traditional medicine, potential anti-inflammatory and pain-relieving activity of Momordica charantia, Azadirachta indica, Nelumbo nucifera, Caesalpinia crista, Martynia annua and Erythrina variegate has been emphasized. In this study, we explored binding affinity of 36 bioactive compounds from these plants to cyclooxygenase-2 (COX-2) receptor using docking method. Six compounds namely, beta carotene, lycopene, lutein, momordicoside, rutin and azadirachtin showed excellent binding affinities (-10.29, -10.22, -10.03, -7.9, -8.81 and -7.88 kcal/mol, respectively) and stable interactions with COX-2 (greater than those of aspirin and diclofenac) and they were chosen for the molecular dynamics (MD) assessments done throughout a 100-ns time period. Based on the computed RMSD, RMSF, Rg, SASA and PCA, all ligands were found to form stable and adequate interactions with COX-2 protein; these findings were comparable to those of aspirin and diclofenac, indicating the potential inhibitory properties of these ligands on COX-2 protein. In addition, the toxicity of compounds was evaluated using Pred-hERG, Pred-Skin and ProTox-II. Since COX-2 inhibitors have been reported to activate the Nrf2 pathway, it is hypothesized that they may confer other health-promoting effects through triggering Nrf2 signaling.

Methanol Extract of Thottea siliquosa (Lam.) Ding Hou Leaves Inhibits Carrageenan- and Formalin-Induced Paw Edema in Mice

Inflammation is a physiological condition that when unattended causes serious health concerns over the long term. Several phytocompounds have emerged as promising sources of anti-inflammatory agents. Thottea siliquosa is a traditional medicine for inflammatory and toxicity insults; however, this has not been scientifically confirmed. The purpose of this study is to evaluate the anti-inflammatory properties of T. siliquosa methanol leaf extract in a mouse model. This study investigates the anti-inflammatory activities of a plant extract obtained from leaves of T. siliquosa (TSE) with a focus on carrageenan- and formalin-induced paw oedema in mice. The extract's efficacy was assessed using well-established inflammation models, and the results showed a considerable reduction in paw edema in both cases. In the case of carrageenan model TSE at 50 mg/kg showed a 53.0 ± 2.5% reduction in edema, while those treated with TSM at 100 mg/kg exhibited a 60.0 ± 1.8% reduction (p < 0.01). In the case of a formalin model when a higher dose of TSE (100 mg/kg) was given, paw thickness decreased by 47.04 ± 1.9% on the fifth day and by 64.72 ± 2.2% on the tenth day. LC-MS analysis reported the presence of gallic acid, quinic acid, quercetin, clitorin, myricitrin, retronecine, batatasin II, gingerol, and coumaric acid in the extract. Overall, this study confirms that T. siliquosa extract exerts anti-inflammatory effects in animals and is possibly mediated through the combined effects of these phytochemicals.

The evolving landscape of IL-10, IL-22 and IL-26 in pleurisy especially in tuberculous pleurisy

Pleurisy can be categorized as primary or secondary, arising from immunological, tumorous, or microbial conditions. It often results in lung structure damage and the development of various respiratory issues. Among the different types, tuberculous pleurisy has emerged as a prominent focus for both clinical and scientific investigations. The IL-10 family, known for its anti-inflammatory properties in the human immune system, is increasingly being studied for its involvement in the pathogenesis of pleurisy. This review aims to present a detailed overview of the intricate role of IL-10 family members (specifically IL-10, IL-22, and IL-26) in human and animal pleuritic diseases or relevant animal models. These insights could serve as valuable guidance and references for further studies on pleurisy and potential therapeutic strategies.

Chlorogenic acid mitigates potassium dichromate-induced acute hepato-nephrotoxicity by attenuating the NF-κB signalling pathway

BACKGROUND

Hexavalent chromium (CrVI) is known to be a potentially hepatotoxic and nephrotoxic contaminant in humans and other animals, whose toxicity is associated with oxidative stress and inflammation. The aim of this study was to evaluate the potential protective effect of chlorogenic acid (CGA), which has known anti-inflammatory and antioxidant effects, on potassium dichromate (PDC)-induced acute hepatotoxicity and nephrotoxicity in rats.

METHODS AND RESULTS

Thirty-six Wistar albino rats were treated with CGA (10, 20, or 40 mg/kg, intraperitoneally) and/or PDC (15 mg/kg/day, intraperitoneally) as a single dose. Serum, liver, and kidney tissues were examined biochemically, histopathologically, and immunohistochemically. Compared to the control group, a significant increase in interleukin-6 (IL-6) levels and a significant decrease in serum and renal reduced glutathione (GSH) levels, liver catalase (CAT), tumour necrosis factor-alpha (TNF-α), and interleukin 1β (IL-1β) levels were observed in the PDC group. The administration of PDC led to histopathological and immunohistochemical changes in rat liver and kidney tissues. With the administration of CGA, especially at the 10 mg/kg dosage, the above-mentioned parameters approached normal levels.

CONCLUSIONS

CGA had antioxidant and anti-inflammatory effects that alleviated PDC-induced acute hepato- and nephrotoxicity.

Ameliorative effect of Alangium chinense (Lour.) Harms on rheumatoid arthritis by reducing autophagy with targeting regulate JAK3-STAT3 and COX-2 pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Alangium chinense has been used as traditional folk medicine for centuries to treat rheumatoid arthritis (RA) by Guizhou Miao nationality with remarkable clinical effect. But the mechanism of its anti-RA is not fully clarified.

AIM OF THE STUDY

To explore the effect and underlying mechanism of A. chinense against RA.

MATERIAL AND METHODS

RA rats were induced by CII/IFA, and oral administrated with or without ethyl acetate extracts of Alangium chinense (ACEE) and tripterygium glycosides (GTW). Then arthritis scores, inflammatory factors in serum and histological evaluation were evaluated to assess the degree of joints disease. Proteomics were conducted via LC-MS/MS to clarify the mechanism of ACEE preliminarily, and further examined by immunohistochemistry, immunofluorescence, western botting, and molecular docking.

RESULTS

ACEE decreased joints swelling, cell abscission and necrosis of joint tissues arthropathy of RA rats, and attenuated expression of TNF-α, IL-1β, IL-6, PGE2, TGF-β. Meanwhile, differentially expressed proteins in the ACEE treated groups were observed, which were involved in RA, spliceosome, cell adhesion molecules, phagosome and lysosome signaling pathways. Moreover, ACEE significantly ameliorated arthropathy, suppressed JAK-STAT pathway (JAK3, p-JAK3, STAT3, iNOS, RANKL), COX-2 pathway (COX-2, TNF-α, IL-6I, L-1β, 5-LOX), and autophagic signaling pathway (LC3-Ⅰ, LC3-Ⅱ, p62, mTOR). But it showed little effect on the expression of COX-1, JAK1, JAK2, TyK2.

CONCLUSION

It is the first evidence that A. chinense significantly ameliorates RA, and the underlying immune mechanism involves reducing autophagy with targeting regulate JAK3-STAT3 and COX-2 pathways.

In vitro and in vivo anti-inflammatory and antiophidic effects of the extract and fraction of Eugenia uniflora

ETHNOPHARMACOLOGICAL RELEVANCE

Eugenia uniflora Linn, popularly known as 'pitanga', is a native plant endemic to Brazil that belongs to the Myrtaceae family. Its traditional use (leaves infusion) has been reported for the treatment of different diseases, including hypertension, inflammation, and as a diuretic agent. Considering the snakebite problem and the rich molecule repertoire of this herbal species, studies that evaluate its antiophidic potential are relevant for a broad social impact.

AIM OF THE STUDY

This approach aims to evaluate the anti-inflammatory and antiophidic potential in vitro and in vivo of the extract (aqueous) and a fraction (ethyl acetate) of E. uniflora leaves against Bothrops leucurus and Bothrops brazili venoms.

MATERIALS AND METHODS

Extract and fraction from E. uniflora leaves were obtained by turbo-extraction and partitioning. The cytotoxicity was assayed on normal cell lines (Vero E6 and 3T3) using the 3-methyl-[4-5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide method. The anti-inflammatory activity of the aqueous extract was analyzed in vivo in the zymosan-induced air pouch model, and the leukocytes migration and other molecular inflammatory mediators quantified (myeloperoxidase, total protein, pro-inflammatory cytokine, malondialdehyde, and glutathione). In vitro, the antiophidic effect was evaluated by the ability of the E. uniflora extract and fraction to inhibit the enzymatic action (proteolytic, phospholipase A2, and hyaluronidase) of B. leucurus and B. brazili venoms. In addition, the antiophidic action in vivo was investigated after treatment with E. uniflora extract and fraction (50, 100, and 200 mg/kg) in the B. leucurus venom-induced paw edema with an evaluation of the antiedematogenic effect and quantification of myeloperoxidase (MPO) and pro-inflammatory cytokine levels.

RESULTS

The E. uniflora leaves extract (7.8-125 mg/mL) revealed no toxicity in cell culture, but reduced MTT by 47% at the highest concentration (250 mg/mL) in Vero E6 cells. In contrast, the E. uniflora fraction (7.8-250 mg/mL) showed no cytotoxicity for both cell lines. In the air pouch model, E. uniflora leaves extract demonstrated anti-inflammatory activity, reducing cell migration, MPO activity, protein, malondialdehyde, and proinflammatory cytokines, and increased glutathione levels. Evaluating the antiophidic action in vitro, E. uniflora extract and fraction inhibited the proteolytic, phospholipase, and hyaluronidase effects of B. leucurus and B. brazili venoms at low concentrations. In addition, the extract and fraction also demonstrated in vivo antiophidic activity by reducing edema in the first 0.5 h after treatment, besides reducing MPO and pro-inflammatory cytokines levels.

CONCLUSION

E. uniflora leaves extract showed cytotoxicity only at the highest concentration while the fraction revealed no toxic effect in vitro. This approach showed for the first time that the aqueous extract and ethyl acetate fraction of E. uniflora leaves has similar antiophidic action in vitro and in vivo, with antiedematogenic and anti-inflammatory effects and the ability to inhibit the enzymatic action of B. leucurus and B. brazili venoms. Therefore, this study points to the presence of bioactive components in the leaves of E. uniflora useful for the treatment of inflammatory disorders and ophidian accidents, expanding the therapeutic potential of this herbal species.

Syringic acid demonstrates an anti-inflammatory effect via modulation of the NF-κB-iNOS-COX-2 and JAK-STAT signaling pathways in methyl cellosolve-induced hepato-testicular inflammation in rats

Syringic acid (SACI) is an emerging nutraceutical and antioxidant used in modern Chinese medicine. It has potential neuroprotective, anti-hyperglycemic, and anti-angiogenic properties. Methyl cellosolve (MCEL) has been reported to induce tissue inflammation in the testis, kidney, liver, and lung. This study aimed to investigate the effect and probable mechanism of action of SACI on MCEL-induced hepatic and testicular inflammation in male rats. Compared to the control group, administration of MCEL to rats significantly increased the levels of IL-6, TNF-α, iNOS, COX-2, and NF-κB in the liver and testis. Additionally, the total mRNA expressions of JAK1 (in the liver only), STAT1, and SOCS1 were significantly increased in both the liver and testis, while testicular JAK1 total mRNA levels were significantly decreased. The expression of PIAS1 protein was significantly higher in the liver and testis. Treatments with SACI at 25 (except liver iNOS), 50, and 75 mg/kg significantly decreased the levels of IL-6, TNF-α, iNOS, COX-2, and NF-κB compared to the control group. Furthermore, the total mRNA expressions of JAK1 and SOCS1 in the liver were significantly reduced by all doses of SACI investigated, while the total mRNA levels of liver and testis STAT1 were significantly reduced by 25 and 50 mg/kg of SACI only. In the testis, the mRNA level of SOCS1 was significantly reduced by all doses of SACI compared to MCEL only. Additionally, SACI (at 75 mg/kg) significantly reduced PIAS1 protein expression in the liver, while in the testis, SACI at all investigated doses significantly reduced the expression of PIAS1. In conclusion, SACI demonstrated a hepatic and testicular anti-inflammatory effect by inhibiting the MCEL-induced activation of the NF-κB and JAK-STAT signaling pathways in rats.

Therapeutic Effects and Molecular Mechanism of Chlorogenic Acid on Polycystic Ovarian Syndrome: Role of HIF-1alpha

Chlorogenic acid (CGA) is a powerful antioxidant polyphenol molecule found in many diets and liquid beverages, playing a preventive and therapeutic role in various diseases caused by oxidative stress and inflammation. Recent research has found that CGA can not only improve clinical symptoms in PCOS patients but also improve follicular development, hormone status, and oxidative stress in PCOS rats, indicating the therapeutic effect of CGA on PCOS. Notably, our previous series of studies has demonstrated the expression changes and regulatory mechanisms of HIF-1alpha signaling in PCOS ovaries. Considering the regulatory effect of CGA on the HIF-1alpha pathway, the present article systematically elucidates the therapeutic role and molecular mechanisms of HIF-1alpha signaling during the treatment of PCOS by CGA, including follicular development, steroid synthesis, inflammatory response, oxidative stress, and insulin resistance, in order to further understand the mechanisms of CGA effects in different types of diseases and to provide a theoretical basis for further promoting CGA-rich diets and beverages simultaneously.

Improved Local Anesthesia at Inflamed Tissue Using the Association of Articaine and Copaiba Oil in Avocado Butter Nanostructured Lipid Carriers

Unsuccessful anesthesia often occurs under an inflammatory tissue environment, making dentistry treatment extremely painful and challenging. Articaine (ATC) is a local anesthetic used at high (4%) concentrations. Since nanopharmaceutical formulations may improve the pharmacokinetics and pharmacodynamics of drugs, we encapsulated ATC in nanostructured lipid carriers (NLCs) aiming to increase the anesthetic effect on the inflamed tissue. Moreover, the lipid nanoparticles were prepared with natural lipids (copaiba (Copaifera langsdorffii) oil and avocado (Persia gratissima) butter) that added functional activity to the nanosystem. NLC-CO-A particles (~217 nm) showed an amorphous lipid core structure according to DSC and XDR. In an inflammatory pain model induced by λ-carrageenan in rats, NLC-CO-A improved (30%) the anesthetic efficacy and prolonged anesthesia (3 h) in relation to free ATC. In a PGE2-induced pain model, the natural lipid formulation significantly reduced (~20%) the mechanical pain when compared to synthetic lipid NLC. Opioid receptors were involved in the detected analgesia effect since their blockage resulted in pain restoration. The pharmacokinetic evaluation of the inflamed tissue showed that NLC-CO-A decreased tissue ATC elimination rate (ke) by half and doubled ATC’s half-life. These results present NLC-CO-A as an innovative system to break the impasse of anesthesia failure in inflamed tissue by preventing ATC accelerated systemic removal by the inflammatory process and improving anesthesia by its association with copaiba oil.

C781, a β-Arrestin Biased Antagonist at Protease-Activated Receptor-2 (PAR2), Displays in vivo Efficacy Against Protease-Induced Pain in Mice

Given the limited options and often harmful side effects of current analgesics and the suffering caused by the opioid crisis, new classes of pain therapeutics are needed. Protease-activated receptors (PARs), particularly PAR2, are implicated in a variety of pathologies, including pain. Since the discovery of the role of PAR2 in pain, development of potent and specific antagonists has been slow. In this study, we describe the in vivo characterization of a novel small molecule/peptidomimetic hybrid compound, C781, as a β-arrestin-biased PAR2 antagonist. In vivo behavioral studies were done in mice using von Frey filaments and the Mouse Grimace Scale. Pharmacokinetic studies were done to assess pharmacokinetic/pharmacodynamic relationship in vivo. We used both prevention and reversal paradigms with protease treatment to determine whether C781 could attenuate protease-evoked pain. C781 effectively prevented and reversed mechanical and spontaneous nociceptive behaviors in response to small molecule PAR2 agonists, mast cell activators, and neutrophil elastase. The ED50 of C781 (intraperitoneal dosing) for inhibition of PAR2 agonist (20.9 ng 2-AT)-evoked nociception was 6.3 mg/kg. C781 was not efficacious in the carrageenan inflammation model. Pharmacokinetic studies indicated limited long-term systemic bioavailability for C781 suggesting that optimizing pharmacokinetic properties could improve in vivo efficacy. Our work demonstrates in vivo efficacy of a biased PAR2 antagonist that selectively inhibits β-arrestin/MAPK signaling downstream of PAR2. Given the importance of this signaling pathway in PAR2-evoked nociception, C781 exemplifies a key pharmacophore for PAR2 that can be optimized for clinical development. PERSPECTIVE: Our work provides evidence that PAR2 antagonists that only block certain aspects of signaling by the receptor can be effective for blocking protease-evoked pain in mice. This is important because it creates a rationale for developing safer PAR2-targeting approaches for pain treatment.

Biological activity of algal derived carrageenan: A comprehensive review in light of human health and disease

Carrageenans are a family of natural linear sulfated polysaccharides derived from red seaweeds and used as a common food additive. Carrageenan's properties, impact on health, and aesthetic benefits have all been studied for a long time; however, the mechanisms are still unclear. In pharmaceutical aspects, carrageenan displayed potential antioxidant and immunomodulatory properties in both in vivo and in vitro action. It also contributes to potential disease-preventive activities through dynamic modulation of important intracellular signaling pathways, regulation of ROS buildup, and preservation of major cell survival and death processes which leads to potential drug development. Furthermore, the chemical synthesis of the current bioactive medicine with confirmational rearrangement may increase availability and bioactivity needs diligent examination. In this review, we give an up-to-date overview of recent research on Carrageenan with reference to health and therapeutic advantages. In addition, we have focused on structural conformation and its primary strategic deployment in disease prevention, as well as the mechanistic investigation of how it functions to combat various disease-preventive employed for future therapeutic interventions. This review may get new insights into the possible novel role of carrageenan and open up a novel disease-preventive mechanism and enhance human health.

Chemical composition and effects of ethanolic extract and gel of Cochlospermum regium (Schrank) Pilg. Leaves on inflammation, pain, and wounds

ETHNOPHARMACOLOGICAL RELEVANCE

Cochlospermum regium is well-known as "Algodãozinho do cerrado" in folk Brazilian medicine, and is used to fight infections, inflammation and skin disorders.

AIM OF THE STUDY

To identify the phytochemical constituents and the effects of the ethanolic extract of C. regium leaves (EECR) on inflammation and pain, and the effects of C. regium gel (GEECR) on wound healing.

MATERIALS AND METHODS

Animals were treated with EECR (30-300 mg/kg) or GEECR (1.25 and 2.5%) and studies were conducted using carrageenan-induced pleurisy and paw edema tests, formalin-induced pain model, and excision wound model.

RESULTS

In total, 25 compounds, including quercitrin, methyl gallate, and 1,2,3,4,6-pentagalloylhexose, with highest detectability were identified. The treatments reduced leukocyte migration, nitric oxide production, protein extravasation, edema, mechanical hyperalgesia, pain in both phases (neurogenic and inflammatory), cold hypersensitivity, and improved wound closure and tissue regeneration.

CONCLUSIONS

The present findings established the anti-inflammatory, anti-nociceptive, and wound healing potential of the leaves of C. regium, confirming the potential therapeutic effect of this plant.

Phytochemical Compounds, Acute Toxicity, Anti-Inflammatory and Antioxidant Activities of Thymus leptobotrys Murb Essential Oil

The present study was conducted to evaluate the acute toxicity and anti-inflammatory effect in vivo, as well as the antioxidant activity, of the essential oil of Thymus leptobotrys Murb. The results indicate that the tested essential oil is non-toxic, with an estimated LD50 of 2500 mg kg^-1 of mice body weight. The anti-inflammatory test revealed that, at a dose of 200 mg kg^-1, the essential oil reduced rat paw edemas by 89.59% within 3 h of oral administration, this reduction in edema size was greater than that obtained with indomethacin (75.78%). The antioxidant activity (IC50) of Thymus leptobotrys Murb essential oil was 346.896 µg mL^-1 and 861.136 mg Trolox equivalent/g essential oil in the 2.2-diphenyl1-picryl-hydrazyl radical scavenging capacity (DPPH) and Trolox equivalent antioxidant capacity (TEAC) assays, respectively. The toxicity test reveals an LD₅₀ greater than 2500 mg kg^-1 of body weight of mice which classifies it within category 5 of non-toxic substances that can be administered orally. These results suggest that the essential oil of Thymus leptobotrys Murb is not toxic, and it represents a valuable source of anti-inflammatory and antioxidant metabolites.

Alloferon-1 ameliorates acute inflammatory responses in λ-carrageenan-induced paw edema in mice

Alloferon-1 have been proposed as an effective peptide to enhance antitumoral immunity, antiviral defense and anti-inflammatory activity. This work aimed to assess anti-inflammatory effects of alloferon-1 against acute inflammation and histopathological deformations in λ-carrageenan-induced paw edema in mice. Systemic pretreatment with alloferon-1 (22.0 mg/kg) intraperitoneally injected mice showed a significant reduction in paw thickness and vascular permeability. Alloferon-1 prevented λ-carrageenan-evoked exudation and the neutrophil influx to the mouse pleura and the neutrophil migration into carrageenan-stimulated mouse air pouches based on the histopathological changes in the paw tissues. Administration of alloferon-1 also suppressed the expression of the inflammatory cytokines in the inflamed paw tissues such as tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein 1 (MCP1), interleukin-5 (IL-5), etc. detected by Luminex liquid chip. Collectively, the present study provides evidences for the marked anti-inflammatory effects of alloferon-1 which might represent new therapeutic options for the treatment of acute inflammatory diseases.

The anti-inflammatory properties of the methanolic extract of Cucumis melo Linn. against prostate enlargement in Wistar rats

In different parts of the world, Cucumis melo Linn. (C melo) is used for its medicinal properties. The present study examined the effects of a methanolic extract of C melo Linn. (F1 hybrid, MECM) on benign prostatic hyperplasia in adult male Wistar rats and evaluated its anti-inflammatory activity in vivo. MECM treatment reduced prostate weight mildly. Histopathological studies showed that the extract produced a strong protective effect against the development of BPH by testosterone. The MECM also showed protection from testosterone-induced benign prostatic hyperplasia (BPH). MECM was tested against carrageenan-induced inflammation in rats' paws to determine its anti-inflammatory activity. It was shown that MECM had a pronounced effect on the inflammatory response in the late phase, i.e., one hour after carrageenan injection. Prostaglandins and nitric oxide are primarily responsible for this phase indicating that MECM can modify the production and release of prostaglandin and nitric oxide. A novel formulation containing C melo may be able to treat the conditions mentioned above.

Phytochemical analysis and preclinical toxicological, antioxidant, and anti-inflammatory evaluation of hydroethanol extract from the roots of Harpalyce brasiliana Benth (Leguminosae)

ETHNOPHARMACOLOGICAL RELEVANCE

Harpalyce brasiliana Benth (Leguminosae) is a shrub endemic to Brazil, popularly known as "snake's root." This species is used in folk medicine for the treatment of inflammation and snakebites. However, up to now there is no scientific research to justify its popular use. The study aimed to characterize the phytochemical profile of the hydroethanol extract from the roots of H. brasiliana (Hb), to evaluate its antioxidant and anti-inflammatory potential, as well as to investigate its cytotoxicity and acute toxicity.

MATERIALS AND METHODS

The extract was obtained by maceration method using a solution of ethanol:water (70: 30, v/v). The phytochemical profile was obtained by liquid chromatography coupled to mass spectrometry. The cytotoxicity of extract (31-2000 μg/mL) was evaluated in vitro, by the 3-methyl-[4-5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) method using murine macrophage and fibroblast cell lines (RAW 247.6 and 3T3, respectively) and by the hemolytic assay. For the in vivo acute toxicity, the extract (2000 mg/kg) was administered and after 14 days the weight (body and organs) and hematological and biochemical parameters were analyzed. Chemical free radical scavenging effect of the extract (125-2000 μg/mL) was investigated through diphenylpicryl hydrazine reduction, total antioxidant capacity, reducing power, hydroxyl radical scavenging, and iron and copper chelating assays. In vitro anti-inflammatory effect of the extract (125, 500, and 2000 μg/mL) was demonstrated through of nitric oxide (NO) analyzed in lipopolysaccharides stimulated RAW 264.7 cells. In vivo anti-inflammatory activities were evaluated in carrageenan-induced paw edema and zymosan-air-pouch models, with gavage administration (post-treatment) of extract at 100, 200, and 400 mg/kg. For the first animal model, the anti-edematogenic activity and myeloperoxidase (MPO) levels were investigated, while in the zymosan-air-pouch model the leukocyte number, MPO, total protein and pro-inflammatory cytokine (IL-1β, IL-6, and TNF-α) levels were quantified. In addition, the oxidative parameters such as malondialdehyde (MDA) and reduced glutathione (GSH) were determined.

RESULTS

The phytochemical profile revealed the presence of 20 compounds, mainly prenylated and geranylated pterocarpans. The extract demonstrated no cytotoxicity in erythrocytes, macrophages and fibroblasts cells at the tested concentrations, as well as no sign of toxicity and mortality or significant alterations on the hematological and biochemical parameters in the acute toxicity model. The extract was also able to neutralize chemical free radicals, with copper and iron chelating effect. For the NO dosage, the extract evidenced the reduction of expression of NO after the administration of the extract (500 and 2000 μg/mL). The edematogenic model revealed a decrease in paw edema and MPO level, while the zymosan-air-pouch model evidenced a reduction of leukocyte number (especially of polymorphornuclears), MPO production, and total protein and cytokine levels, and demonstrated the antioxidant effect through a decrease in MDA and increase in GSH parameters.

CONCLUSION

This approach demonstrates for the first time that Hb is not cytotoxic, has low acute toxicity, and possesses antioxidant and anti-inflammatory properties in preclinical analyses, corroborating its popular use.

GC-MS Analysis and Various In Vitro and In Vivo Pharmacological Potential of Habenaria plantaginea Lindl

Background. The current study aims to give a scientific origin for employing Habenaria plantaginea Lindl. as a potential candidate against nociception, inflammation, and pyrexia. The pharmacological studies were performed on crude extract and subfractions. In the gas chromatography-mass spectroscopy analysis, a total of 21 compounds were identified. The plant samples were displayed for in vitro anti-inflammatory potentials. The observed IC₅₀ for chloroform against cyclooxygenase-2 and 5-lipoxygenase enzymes was 33.81 and 26.74 μg/mL, respectively. The in vivo activities were prerequisites with the acute toxicity studies. In carrageenan-induced inflammation, the chloroform fraction exhibited 46.15% inhibition similar to that of standard drug diclofenac sodium 47.15%. Likewise, in the acetic acid-induced writhing test, the ethyl acetate fraction displayed 71.42% activity, which was dose-dependent as that of standard drug. In Brewer's yeast-induced antipyretic activity, a significant decrease in rectal volume was observed after 30, 60, and 90 minutes. Moreover, the results of this study indicated that the chloroform and ethyl acetate fractions inhibited nociception, inflammation, and pyrexia dose dependently. Likewise, mechanistic insights indicated that naloxone antagonized the antinociceptive effect of chloroform and ethyl acetate fractions, thereby signifying the involvement of opioidergic mechanisms respectively. These results suggest that these molecules present in this plant have synergistically beneficial potential for the cure and management of analgesia, inflammation, and pyrexia.

The role of syringic acid as a neuroprotective agent for neurodegenerative disorders and future expectations

Hundreds of millions of people are influenced by neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD), traumatic disorders of the nervous system, dementia, and various neurological disorders. Syringic acid (SA) is a natural phenolic compound that is found in medicinal herbs and dietary plants. The therapeutic potential of SA is due to its anti-oxidative, chemoprotective, anti-angiogenic, anti-glycating, anti-proliferative, anti-hyperglycaemic, anti-endotoxic, anti-microbial, anti-inflammatory, anti-diabetic and anti-depressant properties. However, in recent studies, its neuroprotective effect has drawn attention. The current review focuses on the neuroprotective bioactivities of SA and putative mechanisms of action. An electronic data search was performed using different search engines, and the relevant articles (with or without meta-analysis) with any language were selected. In the central and peripheral nervous system, SA has been shown a significant role in excitatory neurotransmitters and alleviate behavioral dysfunctions. The consensus of the literature search was that SA treatment may help neurological dysfunction or behavioral impairments management with antioxidant, anti-inflammatory properties. Furthermore, administration and proper dose of SA could be crucial factors for the effective treatment of neurological diseases.

Hydro-ethanol extract of Holarrhena floribunda stem bark exhibits anti-anaphylactic and anti-oedematogenic effects in murine models of acute inflammation

BACKGROUND

Holarrhena floribunda (G.Don) T.Durand & Schinz stem bark has anecdotal use in Ghanaian folk medicine for the management of inflammatory conditions. This study was conducted to investigate the in vivo anti-inflammatory activity of the bark extract using models of acute inflammation in male Sprague Dawley rats, C57BL/6 mice and ICR mice.

METHODS

A 70% hydro-ethanol extract of the stem bark (HFE) was evaluated at doses of 5-500 mg/kg bw. Local anaphylaxis was modelled by the pinnal cutaneous anaphylactic test. Systemic anaphylaxis or sepsis were modeled by compound 48/80 or lipopolysaccharide, respectively. Clonidine-induced catalepsy was used to investigate the effect on histamine signaling. Anti-oedematogenic effect was assessed by induction with carrageenan. Effects on mediators of biphasic acute inflammation were studied using histamine and serotonin (early phase) or prostaglandin E2 (late phase).

RESULTS

HFE demonstrated anti-inflammatory and/or anti-oedematogenic activity comparable to standard doses of aspirin and diclofenac (inhibitors of cyclooxygenases-1 and -2), chlorpheniramine (histamine H1-receptor antagonist), dexamethasone (glucocorticoid receptor agonist), granisetron (serotonin receptor antagonist) and sodium cromoglycate (inhibitor of mast cell degranulation). All observed HFE bioactivities increased with dose.

CONCLUSIONS

The data provide evidence that the extract of H. floribunda stem bark has anti-anaphylactic and anti-oedematogenic effects; by interfering with signalling or metabolism of histamine, serotonin and prostaglandin E2 which mediate the progression of inflammation. The anti-inflammatory and antihistaminic activities of HFE may be relevant in the context of the management of COVID-19.

Restorative and pain-relieving effects of fibroin in preclinical models of tendinopathy

The term tendinopathy indicates a wide spectrum of conditions characterized by alterations in tendon tissue homeostatic response and damage to the extracellular matrix. The current pharmacological approach involves the use of nonsteroidal anti-inflammatory drugs and corticosteroids often with unsatisfactory results, making essential the identification of new treatments. In this study, the pro-regenerative and protective effects of an aqueous fibroin solution (0.5-500 μg/mL) against glucose oxidase (GOx)-induced damage in rat tenocytes were investigated. Then, fibroin anti-hyperalgesic and protective actions were evaluated in two models of tendinopathy induced in rats by collagenase or carrageenan injection, respectively. In vitro, 5-10 μg/mL fibroin per se increased cell viability and reverted the morphological alterations caused by GOx (0.1 U/mL). Fibroin 10 μg/mL evoked proliferative signaling upregulating the expression of decorin, scleraxin, tenomodulin (p < 0.001), FGF-2, and tenascin-C (p < 0.01) genes. Fibroin enhanced the basal FGF-2 and MMP-9 protein concentrations and prevented their GOx-mediated decrease. Furthermore, fibroin positively modulated the production of collagen type I. In vivo, the peri-tendinous injection of fibroin (5 mg) reduced the development of spontaneous pain and hypersensitivity (p < 0.01) induced by the intra-tendinous injection of collagenase; the efficacy was comparable to that of triamcinolone. The pain-relieving action of fibroin (peri-tendinous) was confirmed in the model of tendinopathy induced by carrageenan (intra-tendinous) where this fibrous protein was also able to improve tendon matrix organization, normalizing the orientation of collagen fibers. In conclusion, the use of fibroin in tendinopathies is suggested taking advantage of its excellent mechanical properties, pain-relieving effects, and ability to promote tissue regeneration processes.

Recent development on COX-2 inhibitors as promising anti-inflammatory agents: The past 10 years

Cyclooxygenases play a vital role in inflammation and are responsible for the production of prostaglandins. Two cyclooxygenases are described, the constitutive cyclooxygenase-1 and the inducible cyclooxygenase-2, for which the target inhibitors are the non-steroidal anti-inflammatory drugs (NSAIDs). Prostaglandins are a class of lipid compounds that mediate acute and chronic inflammation. NSAIDs are the most frequent choices for treatment of inflammation. Nevertheless, currently used anti-inflammatory drugs have become associated with a variety of adverse effects which lead to diminished output even market withdrawal. Recently, more studies have been carried out on searching novel selective COX-2 inhibitors with safety profiles. In this review, we highlight the various structural classes of organic and natural scaffolds with efficient COX-2 inhibitory activity reported during 2011–2021. It will be valuable for pharmaceutical scientists to read up on the current chemicals to pave the way for subsequent research.

Embelia Laeta aqueous extract suppresses acute inflammation via decreasing COX-2/iNOS expression and inhibiting NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

The root of Embelia laeta (L.) Mez., which is called Suanjifeng in Chinese ethnic Yao medicine, is traditionally for inflammation-related diseases, such as oral ulcer, sore throat, enteritis, and rheumatoid arthritis. However, the biological properties and the underlying mechanisms of Embelia laeta still need further studies.

AIM OF THIS STUDY

The present study aims to investigate the anti-inflammatory effect and its underlying mechanisms of Embelia laeta.

MATERIALS AND METHODS

In this study, except acute toxicity experiments, Kunming (KM) mice of either sex were enrolled to establish inflammatory model induced by xylene, acetic acid and carrageenan, respectively. Mice were randomly divided into different groups and pretreated by oral gavage with different doses of Embelia laeta aqueous extract (ELAE) (2.5, 5, 10 g/kg) and 10 mg/kg of Indo for 7 days. Ear edema, vascular permeability, abdominal writhing, and paw edema degree were detected in related experiments. Moreover, in the carrageenan-induced paw edema mice model, histological changes were detected by H&E staining. MDA, MPO and NO were detected by assay kit. Proinflammatory cytokines of IFN-γ, TNF-α, IL-1β, IL-6 and PGE₂ were detected by ELISA. Additionally, COX-2, iNOS and NF-κB pathway-related proteins were detected by Western blotting.

RESULTS

Results showed that the ELAE evoked an obvious dose-dependent inhibition of ear edema induced by xylene, paw edema induced by carrageenan, as well as suppressing the increase of vascular permeability and writhing times elicited by acetic acid. Histopathological analysis indicated that ELAE could significantly decrease the cellular infiltration in paw tissue. ELAE showed antioxidant property through markedly decrease the MDA level and MPO activity in edema paw. In addition, ELAE decreased the proinflammatory cytokines IFN-γ, TNF-α, IL-1β, IL-6, PGE₂ and NO that induced by carrageenan. Western blotting results also showed that ELAE could obviously downregulate the COX-2 and iNOS expression. Further analysis revealed that ELAE also inhibited NF-κB from the cytoplasm to the nucleus and stabilize the conversion of IκBα.

CONCLUSION

ELAE had powerful anti-inflammatory property, which might be had a close relationship with mediating proinflammatory cytokines production, decreasing the COX-2 and iNOS expression, and inhibiting the activation of NF-κB signaling pathway.

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.

Anti-inflammatory activity and chemical composition of aqueous extract and essential oil from leaves of Ocimum selloi Benth

ETHNOPHARMACOLOGICAL RELEVANCE

The population uses the aqueous extract as tea from leaves of Ocimum selloi Benth. (alfavaca) for pain and inflammation issues. This study is motivated by a lack of data about inflammation properties of O. selloi.

AIM OF THE STUDY

This study investigated the chemical composition and anti-inflammatory activity, in mice models, of the aqueous extract (OSAE) and essential oil (OSEO) obtained from leaves of O. selloi.

MATERIALS AND METHODS

The antioxidant activity and total phenolic content were evaluated for samples, although chemical composition was obtained by U-HPLC-DAD-ESI-MS for OSAE and GC-MS for OSEO. OSAE and OSEO were tested orally at doses of 30, 100 and 300 mg/kg at the carrageenan-induced pleurisy and paw edema, also mechanical hyperalgesia, in mice.

RESULTS

Four glycosylated flavonoids and one organic acid were identified in OSAE, and nine substances in OSEO, the two majoritarian are E-anethole and methyl chavicol. Oral treatments with OSAE and OSEO significantly inhibited the carrageenan-induced pleurisy in female Swiss mice, besides OSAE and OSEO significantly prevented paw edema (after 1, 2, and 4 h), mechanical hyperalgesia (after 3 and 4 h), and cold hyperalgesia 3 h after carrageenan model in male Swiss mice. The dose of 300 mg/kg of OSEO reduced cold hyperalgesia 4 h after carrageenan.

CONCLUSION

The results evidenced the anti-inflammatory, anti-edematogenic, anti-hyperalgesic, and anti-nociceptive potentials of both materials obtained from leaves of O. selloi, mainly OSAE, supporting the popular use of this species.

TRPV1 Blocker HCRG21 Suppresses TNF-α Production and Prevents the Development of Edema and Hypersensitivity in Carrageenan-Induced Acute Local Inflammation

Currently the TRPV1 (transient receptor potential vanilloid type 1) channel is considered to be one of the main targets for pro-inflammatory mediators including TNF-α. Similarly, the inhibition of TRPV1 activity in the peripheral nervous system affects pro-inflammatory mediator production and enhances analgesia in total. In this study, the analgesic and anti-inflammatory effects of HCRG21, the first peptide blocker of TRPV1, were demonstrated in a mice model of carrageenan-induced paw edema. HCRG21 in doses of 0.1 and 1 mg/kg inhibited edema formation compared to the control, demonstrated complete edema disappearance in 24 h in a dose of 1 mg/kg, and effectively reduced the productionof TNF-α in both doses examined. ELISA analysis of blood taken 24 h after carrageenan administration showed a dramatic cytokine value decrease to 25 pg/mL by HCRG21 versus 100 pg/mL in the negative control group, which was less than the TNF-α level in the intact group (40 pg/mL). The HCRG21 demonstrated potent analgesic effects on the models of mechanical and thermal hyperalgesia in carrageenan-induced paw edema. The HCRG21 relief effect was comparable to that of indomethacin taken orally in a dose of 5 mg/kg, but was superior to this nonsteroidal anti-inflammatory drug (NSAID) in duration (which lasted 24 h) in the mechanical sensitivity experiment. The results confirm the existence of a close relationship between TRPV1 activity and TNF-α production once again, and prove the superior pharmacological potential of TRPV1 blockers and the HCRG21 peptide in particular.

Responsive optical probes for deep-tissue imaging: Photoacoustics and second near-infrared fluorescence

Optical imaging has played a vital role in development of biomedicine and image-guided theragnostic. Nevertheless, the clinical translation of optical molecular imaging for deep-tissue visualization is still limited by poor signal-to-background ratio and low penetration depth owing to light scattering and tissue autofluorescence. Hence, to facilitate precise diagnosis and accurate surgery excision in clinical practices, the responsive optical probes (ROPs) are broadly designed for specific reaction with biological analytes or disease biomarkers via chemical/physical interactions for photoacoustic and second near-infrared fluorescence (NIR-II, 900-1700 nm) fluorescence imaging. Herein, the recent advances in the development of ROPs including molecular design principles, activated mechanisms and treatment responses for photoacoustic and NIR-II fluorescence imaging are reviewed. Furthermore, the present challenges and future perspectives of ROPs for deep-tissue imaging are also discussed.

Cannabis roots: Pharmacological and toxicological studies in mice

ETHNOPHARMACOLOGICAL RELEVANCE

There are many studies and therapeutic properties attributed to the flowers and leaves of the Cannabis species, but even with few pharmacological studies, Cannabis sativa L. (Cannabaceae) roots presents several therapeutic indications in folk medicine.

AIM OF THE STUDY

This study aimed to evaluate the anti-inflammatory and spasmolytic effects as well as the toxicological profile of the aqueous extract of Cannabis sativa roots (CsAqEx) in mice.

MATERIALS AND METHODS

We assessed the anti-inflammatory effect with carrageenan-induced leukocyte migration assay, and carrageenan and histamine-induced paw edema methods; The spasmolytic effect was assessed through in vitro assays with isolated mice trachea. To assess motor coordination and mobility, mice went through the rotarod and open field tests, respectively. For the single-dose toxicity study, we administered CsAqEx at the dose of 1000 mg/kg by gavage. In a repeated dose toxicity study, animals received CsAqEx at doses of 25 mg or 100 mg/kg for 28 days.

RESULTS

The CsAqEx inhibited the migration of leukocytes at the doses of 25, 50, and 100 mg/kg. The CsAqEx showed anti-inflammatory activity after the intraplantar injection of carrageenan, presenting a reduction in edema formation at all tested doses (12.5, 25, 50 and 100 mg/kg). The dose of 12.5 mg/kg of CsAqEx prevented edema formation after intraplantar injection of histamine. In an organ bath, 729 μg/mL of CsAqEx did not promote spasmolytic effect on isolated mice tracheal rings contracted by carbachol (CCh) or potassium chloride (KCl). We did not observe clinical signs of toxicity in the animals after acute treatment with CsAqEx, which suggested that the median lethal dose (LD₅₀) is greater than 1000 mg/kg. Repeated dose exposure to the CsAqEx did not produce significant changes in hematological, biochemical, or organ histology parameters.

CONCLUSIONS

The results suggest that the anti-inflammatory effect of CsAqEx is related to the reduction of vascular extravasation and migration of inflammatory cells, without effects on the central nervous system. Moreover, there was no spasmolytic effect on airway smooth muscle and no toxicity was observed on mice.

Mycophenolate suppresses inflammation by inhibiting prostaglandin synthases: a study of molecular and experimental drug repurposing

Mycophenolate mofetil is an established anti-proliferative and immune-suppressive agent that minimizes the proliferation of inflammatory cells by interfering with nucleic acid synthesis. Herein, we report our discovery of the prostaglandin inhibiting properties of MMF, which offers new applications for the drug in the treatment of inflammatory diseases. The estimated values of IC₅₀MMF_COX-1, IC₅₀MMF_COX-2, and IC₅₀MMF_5-LOX were 5.53, 0.19, and 4.47 µM, respectively. In contrast, mycophenolic acid (MPA) showed slightly stronger inhibition: IC₅₀MPA_COX-1, IC₅₀MPA_COX-2, and IC₅₀MPA_5-LOX were 4.62, 0.14, and 4.49 µM, respectively. These results indicate that MMF and MPA are, respectively, 28.6 and 33 times more selective for cyclooxygenase-2 than for cyclooxygenase-1, which implies that MMF would have less impact on the gastric mucosa than most nonselective, nonsteroidal anti-inflammatory drugs. Furthermore, MMF provided dose-dependent relief of acute inflammation in the carrageenan-induced rat paw edema test, with results comparable to those of celecoxib and indomethacin. Molecular dynamics simulations indicated that the MMF bond with COX-2 was stable, as evidenced by a low root-mean-square deviation of atomic positions, complementary per-residue root-mean-square fluctuation, and 0–4 hydrogen bonds during the 50-ns simulation time. Therefore, MMF provides immune-suppressing, cyclooxygenase-inhibiting, and inflammation-relieving properties. Our results indicate that MMF can be 1) repositioned for inflammation treatment without the need for further expensive clinical trials, 2) used for local acute inflammations, and 3) used as a sparing agent for other steroid and non-steroid anti-inflammatory medications, especially in topical applications.

Etodolac nanosuspension based gel for enhanced dermal delivery: in vitro and in vivo evaluation

AIM

The objective of this study was to develop dermal nanosuspension (NS) based gel formulation of etodolac (ETD).

METHODS

Etodolac nanosuspension (ETD-NS) was prepared by wet milling method and dispersed in hydroxypropyl methylcellulose (NS-HPMC) or hydroxyethyl cellulose (NS-HEC) gels. Rheologic and mechanical properties were investigated. In vitro and ex vivo permeability studies were performed. Topical anti-inflammatory and analgesic activity were evaluated in regard to carrageenan-induced inflammatory paw oedema and radiant heat tail-flick method, respectively.

RESULTS

The ETD-NS with approximately 190 nm particle size (PS), 0.16 polydispersity index (PDI), and -15 mV zeta potential (ZP) values were obtained. The work of bioadhesion values of NS-HEC and NS-HPMC gels were 0.229 mJ/cm² for both gels. Dermal permeation of ETD from NS-HEC gel (7.18%) was found significantly higher than the NS-HPMC gel (4.56%). Enhanced anti-inflammatory and analgesic activity of NS-HEC gels were observed in comparison with micronised ETD.

CONCLUSIONS

ETD-NS based gel formulation is promising for topical delivery of ETD.

Anti-Photoaging and Potential Skin Health Benefits of Seaweeds

The skin health benefits of seaweeds have been known since time immemorial. They are known as potential renewable sources of bioactive metabolites that have unique structural and functional features compared to their terrestrial counterparts. In addition, to the consciousness of green, eco-friendly, and natural skincare and cosmetics products, their extracts and bioactive compounds such as fucoidan, laminarin, carrageenan, fucoxanthin, and mycosporine like amino acids (MAAs) have proven useful in the skincare and cosmetic industries. These bioactive compounds have shown potential anti-photoaging properties. Furthermore, some of these bioactive compounds have been clinically tested and currently available in the market. In this contribution, the recent studies on anti-photoaging properties of extracts and bioactive compounds derived from seaweeds were described and discussed.

Pharmacologic Overview of Chlorogenic Acid and its Metabolites in Chronic Pain and Inflammation

BACKGROUND

Natural phenolic compounds in medicinal herbs and dietary plants are antioxidants which play therapeutic or preventive roles in different pathological situations, such as oxidative stress and inflammation. One of the most studied phenolic compounds in the last decade is chlorogenic acid (CGA), which is a potent antioxidant found in certain foods and drinks.

OBJECTIVE

This review focuses on the anti-inflammatory and antinociceptive bioactivities of CGA, and the putative mechanisms of action are described. Ethnopharmacological reports related to these bioactivities are also reviewed.

MATERIALS AND METHODS

An electronic literature search was conducted by authors up to October 2019. Original articles were selected.

RESULTS

CGA has been shown to reduce inflammation and modulate inflammatory and neuropathic pain in animal models.

CONCLUSION

The consensus of the literature search was that systemic CGA may facilitate pain management via bolstering antioxidant defenses against inflammatory insults.

Molecular Pathways Linking Oxylipins to Nociception in Rats

Oxylipins are lipid peroxidation products that participate in nociceptive, inflammatory, and vascular responses to injury. Effects of oxylipins depend on tissue-specific differences in accumulation of precursor polyunsaturated fatty acids and the expression of specific enzymes to transform the precursors. The study of oxylipins in nociception has presented technical challenges leading to critical knowledge gaps in the way these molecules operate in nociception. We applied a systems-based approach to characterize oxylipin precursor fatty acids, and expression of genes coding for proteins involved in biosynthesis, transport, signaling and inactivation of pro- and antinociceptive oxylipins in pain circuit tissues. We further linked these pathways to nociception by demonstrating intraplantar carrageenan injection induced gene expression changes in oxylipin biosynthetic pathways. We determined functional-biochemical relevance of the proposed pathways in rat hind paw and dorsal spinal cord by measuring basal and stimulated levels of oxylipins throughout the time-course of carrageenan-induced inflammation. Finally, when oxylipins were administered by intradermal injection we observed modulation of nociceptive thermal hypersensitivity, providing a functional-behavioral link between oxylipins, their molecular biosynthetic pathways, and involvement in pain and nociception. Together, these findings advance our understanding of molecular lipidomic systems linking oxylipins and their precursors to nociceptive and inflammatory signaling pathways in rats. PERSPECTIVE: We applied a systems approach to characterize molecular pathways linking precursor lipids and oxylipins to nociceptive signaling. This systematic, quantitative evaluation of the molecular pathways linking oxylipins to nociception provides a framework for future basic and clinical research investigating the role of oxylipins in pain.

Significant action of Tridax procumbens L. leaf extract on reducing the TNF-α and COX-2 gene expressions in induced inflammation site in Swiss albino mice

The leaves of traditionally used herbal plant Tridax procumbens L. contain lots of phytochemicals having potency to reduce inflammation. In this study, the ethanol extract of the leaves of Tridax procumbens L. was analysed for the phytochemicals by GC-MS. The anti-inflammatory activity was then studied with the extract of 10, 50, and 100 mg/kg b.wt in carrageenan-induced mice model by measuring the inflammatory oedema and by analysing the histopathology. The mRNA expression levels of TNF-α and COX2 genes were studied in the inflammatory site to explore the molecular action by reverse transcription PCR and qPCR analyses. A significant (P ≤ 0.01) reduction in mice paw inflammation and a recovered histology were observed in treated groups when compared to control group in 24 h. The RT-PCR results showed a significant (P ≤ 0.01) decrease in the expression levels of TNF-α and COX2 in terms of band density in treated mice compared to control group. The qPCR RQ values also were decreased in treated groups with respect to increasing doses (RQ values of 18.985 ± 0.230, 12.140 ± 1.121, 6.718 ± 0.807 for TNF-α and 15.583 ± 1.043, 7.725 ± 1.013, 5.075 ± 0.615 for COX2, respectively for the three doses) in comparison with the control group (TNF-α 27.107 ± 2.254, COX2 20.626 ± 1.477). Tridax procumbens L. can be, thus, used for the development of a safe, natural, anti-inflammatory drug as it showed a strong inhibitory action on inflammation by acting at molecular level.

Inhibition of carrageenan-induced dental inflammatory responses owing to decreased TRPV1 activity by Dexmedetomidine

Background

Dexmedetomidine (Dex) is a highly selective agonist of the α2 adrenergic receptor and a common sedative; however, its anti-inflammatory effect has been studied. In this study, the inhibitory effect of Dex on inflammation in dental pulp cells was assessed. For this, the effect of Dex on inflammation induced by carrageenan (Car) in human dental pulp cells (hDPCs) was evaluated. Car incubation induced a robust inflammatory response in hDPCs as well as activation of PKA–STAT3 and PKC–nuclear factor kappa B (NF-κB) signaling pathways.

Results

Dex reduced the expression of inflammatory cytokines in a dose-dependent manner. Meanwhile, the phosphorylation of PKA, PKC, STAT3, and NF-κB as well as the nuclear accumulation of STAT3 and NF-κB were significantly increased in Dex-treated Car-induced hDPCs. Western blotting results also showed that the phosphorylation level of transient receptor potential cation channel subfamily V member 1 (TRPV1) was downregulated as a result of Dex treatment. Furthermore, we found that administration of the TRPV1 agonist capsaicin (Cap) reversed the effects of Dex on proinflammatory cytokines; however, the expression and activation of PKA–STAT3 and PKC–NF-κB signals were not altered owing to Cap administration.

Conclusions

These results indicate that Dex plays a defensive role in dental pulp inflammation by regulating the TRPV1 channel and can be used as a potential target for human dental pulp inflammation intervention.

Analgesic, anti-inflammatory and antipyretic activities of ethanolic extract of stem bark of Anogeissus latifolia Roxb

Background

Stem bark of Anogeissus latifolia Roxb (family: Combretaceae) is used traditionally and ethnomedicinally to alleviate pain, inflammation and fever conditions. The current study investigates the analgesic, anti-inflammatory and antipyretic activities of ethanolic extract of stem bark of Anogeissus latifolia Roxb.

Method

The HPLC studies were carried out to standardize the stem bark ethanolic extract of Anogeissus latifolia (ALEE) using ellagic acid as a marker. ALEE was screened for analgesic (formalin-induced pain and acetic acid induced writhing) and anti-inflammatory (formalin and carrageenan-induced paw oedema) activities in Wistar rats. Before 1 h of acetic acid or formalin or carrageenan injection, rats were orally fed with ALEE (100, 200 and 400 mg/kg), Aspirin (100 mg/kg) or Indomethacin (10 mg/kg). Antipyretic effect was studied in brewer’s yeast-induced pyrexia model in rats using Paracetamol (100 mg/kg) as a standard drug.

Results

HPLC analysis of ALEE revealed the presence of ellagic acid. ALEE treatment (200 and 400 mg/kg) significantly inhibited pain response in both models. ALEE treatments prevented the raise of paw volume in both in-vivo models with percent inhibition of 44.40 and 46.21, respectively at 5 h. ALEE also showed a significant reduction of yeast-induced pyrexia till 4 h of treatment.

Conclusion

ALEE exhibited analgesic, anti-inflammatory and antipyretic property in experimental models and validates traditional use of ALEE in pain, inflammation and fever.

Low-intensity ultrasound attenuates paw edema formation and decreases vascular permeability induced by carrageenan injection in rats

Background

Therapeutic potential of low-intensity ultrasound (LIUS) has become evident in various musculoskeletal diseases. We have previously shown that LIUS has an inhibitory effect on local edema in various diseases including the arthritis and brain injury. In this study, we examined whether LIUS can attenuate paw edema formation vis-à-vis vascular permeability and inflammation in rats induced by carrageenan. LIUS with a frequency of 1 MHz and the intensities of 50, 100, or 200 mW/cm² were exposed on rat paws for 10 min immediately after carrageenan injection.

Results

Carrageenan injection induced paw edema which was peaked at 6 h and gradually decreased nearly to the initial baseline value after 72 h. LIUS showed a significant reduction of paw edema formation at 2 and 6 h at all intensities tested. The highest reduction was observed at the intensity of 50 mW/cm². Histological analyses confirmed that LIUS clearly decreased the carrageenan-induced swelling of interstitial space under the paw skin and infiltration of polymorphonuclear leukocytes. Moreover, Evans Blue extravasation analyses exhibited a significant decreases of vascular permeability by LIUS. Finally, immunohistochemical staining showed that expression of pro-inflammatory proteins, namely, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) induced by carrageenan injection was reduced back to the normal level after LIUS stimulation.

Conclusions

These results provide a new supporting evidence for LIUS as a therapeutic alternative for the treatment of edema in inflammatory diseases such as cellulitis.

Psychotria leiocarpa Extract and Vincosamide Reduce Chemically-Induced Inflammation in Mice and Inhibit the Acetylcholinesterase Activity

Species from Psychotria are used in folk medicine against inflammatory diseases, respiratory disturbances, and anti-hallucinogenic. In the present study, the compound vincosamide (PL-1) was identified for the first time in methanolic extract of the Psychotria leiocarpa (ME-PL) leaves, as well as the anti-inflammatory and anticholinesteric effects in rodents and molecular docking simulations. The fractionation of the chloroform fraction (CF-PL) through chromatographic methods afforded the known compound PL-1. The anti-inflammatory activity of the ME-PL (30, 100, and 300 mg/kg) and PL-1 (3, 30, and 100 mg/kg) was analyzed using experimental models: paw edema, pleurisy, and mechanical and thermal hyperalgesia induced by carrageenan. The anticholinesterase activity of the ME-PL (30 and 100 mg/kg) and PL-1 (30 mg/kg) was showed by acetylcholinesterase (AChE) inhibitory in brain structures. The molecular docking simulations were performed using Molegro Virtual Docker v6.0. Overall, the results indicated that ME-PL and PL-1 demonstrated an anti-edematogenic effect in Cg-induced paw edema, leukocyte migration in the pleurisy model, and significantly reduced mechanical hyperalgesia, cold response to acetone in mice. The samples exhibited maximal inhibition of enzyme acetylcholinesterase (AChE) in the frontal cortex. The molecular coupling of PL-1 with the AChE showed significant interactions with the catalytic and peripheral site, corroborating the activity presented in the inhibition assay. The acute administration of ME-PL did not cause signs of toxicity in the treated animals. The results showed that P. leiocarpa inhibited AChE and anti-inflammatory activity, and alkaloid vincosamide could be responsible, at least in part, for the observed effects, supporting the popular use of this genus.

Muscovite nanoparticles mitigate neuropathic pain by modulating the inflammatory response and neuroglial activation in the spinal cord

Despite numerous efforts to overcome neuropathic pain, various pharmacological drugs often fail to meet the needs and have many side effects. Muscovite is an aluminosilicate mineral that has been reported to have an anti-inflammatory effect, but the efficacy of muscovite for neuropathic pain has not been investigated. Here, we assessed whether muscovite nanoparticles can reduce the symptoms of pain by controlling the inflammatory process observed in neuropathic pain. The analgesic effects of muscovite nanoparticles were explored using partial sciatic nerve ligation model of neuropathic pain, in which one-third to one-half of the nerve trifurcation of the sciatic nerve was tightly tied to the dorsal side. Muscovite nanoparticles (4 mg/100 μL) was given intramuscularly to evaluate its effects on neuropathic pain (3 days per week for 4 weeks). The results showed that the muscovite nanoparticle injections significantly alleviated partial sciatic nerve ligation-induced mechanical and cold allodynia. In the spinal cord, the muscovite nanoparticle injections exhibited inhibitory effects on astrocyte and microglia activation and reduced the expression of pro-inflammatory cytokines, such as interleukin-1β, tumor necrosis factor-α, interleiukin-6 and monocyte chemoattractant protein-1, which were upregulated in the partial sciatic nerve ligation model. Moreover, the muscovite nanoparticle injections resulted in a decrease in activating transcription factor 3, a neuronal injury marker, in the sciatic nerve. These results suggest that the analgesic effects of muscovite nanoparticle on partial sciatic nerve ligation-induced neuropathic pain may result from inhibiting activation of astrocytes and microglia as well as pro-inflammatory cytokines. We propose that muscovite nanoparticle is a potential anti-nociceptive candidate for neuropathic pain. All experimental protocols in this study were approved by the Institutional Animal Ethics Committee (IACUC) at Dongguk University, South Korea (approval No. 2017-022-1) on September 28, 2017.

Plasma metabonomics and proteomics studies on the anti-thrombosis mechanism of aspirin eugenol ester in rat tail thrombosis model

Aspirin eugenol eater (AEE), a new drug compound, was synthesized through the combination of aspirin and eugenol. Antithrombotic effects of AEE have been confirmed in carrageenan-induced rat tail thrombosis model. However, its mechanism is unclear. With the application of integrated approach combining proteomics and metabolomics, the profilings of protein and metabolite in plasma were examined in thrombosis rat pretreated with AEE, aspirin and eugenol, respectively. A clear separation of the plasma metabolic profiles from different groups was found in score plots. 15 metabolites related with the metabolism of fatty acid, energy and amino acid were found. A total of 144, 38, 41 and 54 differentially abundant proteins (DAPs) were identified in control, AEE, aspirin and eugenol group, respectively. Proteomic results showed that aspirin modulated 7 proteins in amino acid metabolism and 4 proteins in complement system; eugenol regulated the 8 proteins related with coagulation cascades and fibrinogen; AEE improved 3 proteins in TCA cycle and 3 in lipid metabolism. Integrated analysis suggested that AEE improved fatty acid, energy and lipid metabolism to against thrombosis. Results of this study indicated AEE had different action mechanism on thrombosis from aspirin and eugenol, and contribute to understanding the mechanisms of AEE on thrombosis. SIGNIFICANCE: Thrombosis is a threat to human health, and there is an urgent need for new drug. In this study, compared with the model group, plasma metabolic profiles in AEE-treated rats were clearly separated; 15 metabolites and 38 proteins were picked out. These metabolites and proteins may assist in understanding the action mechanism of AEE on thrombosis. The results of plasma metabonomics and proteomics also revealed the different action mechanism among AEE, aspirin and eugenol on thrombosis. This study established the foundation to further evaluate the druggability of AEE on thrombosis treatment.

Enhancement of acid-sensing ion channel activity by prostaglandin E2 in rat dorsal root ganglion neurons

Prostaglandin E2 (PGE2) and proton are typical inflammatory mediators. They play a major role in pain processing and hypersensitivity through activating their cognate receptors expressed in terminals of nociceptive sensory neurons. However, it remains unclear whether there is an interaction between PGE2 receptors and proton-activated acid-sensing ion channels (ASICs). Herein, we show that PGE2 enhanced the functional activity of ASICs in rat dorsal root ganglion (DRG) neurons through EP1 and EP4 receptors. In the present study, PGE2 concentration-dependently increased ASIC currents in DRG neurons. It shifted the proton concentration-response curve upwards, without change in the apparent affinity of proton for ASICs. Moreover, PGE2 enhancement of ASIC currents was partially blocked by EP1 or EP4 receptor antagonist. PGE2 failed to enhance ASIC currents when simultaneous blockade of both EP1 and EP4 receptors. PGE2 enhancement was partially suppressed after inhibition of intracellular PKC or PKA signaling, and completely disappeared after concurrent blockade of both PKC and PKA signaling. PGE2 increased significantly the expression levels of p-PKCε and p-PKA in DRG cells. PGE2 also enhanced proton-evoked action potentials in rat DRG neurons. Finally, peripherally administration of PGE2 dose-dependently exacerbated acid-induced nocifensive behaviors in rats through EP1 and EP4 receptors. Our results indicate that PGE2 enhanced the electrophysiological activity of ASICs in DRG neurons and contributed to acidosis-evoked pain, which revealed a novel peripheral mechanism underlying PGE2 involvement in hyperalgesia by sensitizing ASICs in primary sensory neurons.

Synthesis and Biological Evaluation of Polyfluoroalkylated Antipyrines and their Isomeric O-Methylpyrazoles

Background:

Formally belonging to the non-steroidal anti-inflammatory drug class pyrazolones have long been used in medical practices.

Objective:

Our goal is to synthesize N-methylated 1-aryl-3-polyfluoroalkylpyrazolones as fluorinated analogs of antipyrine, their isomeric O-methylated derivatives resembling celecoxib structure and evaluate biological activities of obtained compounds.

Methods:

In vitro (permeability) and in vivo (anti-inflammatory and analgesic activities, acute toxicity, hyperalgesia, antipyretic activity, “open field” test) experiments. To suggest the mechanism of biological activity, molecular docking of the synthesized compounds was carried out into the tyrosine site of COX-1/2.

Conclusion:

The trifluoromethyl antipyrine represents a valuable starting point in design of the lead series for discovery new antipyretic analgesics with anti-inflammatory properties.

Evaluation of the toxicity and anti-inflammatory activities of the infusion of leaves of Campomanesia guazumifolia (Cambess.) O. Berg

ETHNOPHARMACOLOGICAL RELEVANCE

Some species of Campomanesia are used in the folk medicine due to anti-inflammatory, anti-diarrheal, anti-diabetes and hypercholesterolemic. However studies with Campomanesia guazumifolia (Cambess.) O. Berg. are scarce.

AIM OF THE STUDY

This study investigated the anti-inflammatory activity and toxicological profile of infusion obtained from leaves of Campomanesia guazumifolia in mice.

MATERIALS AND METHODS

Leaves infusion of C. guazumifolia was obtained in the proportion of 20 g/L (leaves/water) at 95-100 °C for 10 min in an enclosed container. The acute toxicity of the leaves infusion of C. guazumifolia lyophilized (ICG) was assessed by oral administration to female mice at doses of 500, 1000, 2000, and 5000 mg/kg, and the general behavior and toxic symptoms were observed for 14 days. In the subacute toxicity model, female mice were treated orally with the ICG (250, 500, and 1000 mg/kg) during 28 days, and biochemical, toxic signs and the estrous cycle were evaluated. The anti-inflammatory activity of the ICG (70, 300 and 700 mg/kg) was analyzed using carrageenan-induced pleurisy and inflammatory paw (mechanical and thermal hyperalgesia).

RESULTS

Three flavonoids glycosylated and a cyclohexanecarboxylic acid were identified in the ICG: quercetin pentose, quercetin deoxyhexoside, myricetin deoxyhexoside and quinic acid. No clinical signs of acute toxicity were observed, suggesting that the LD₅₀ (Lethal Dose) is above 5000 mg/kg. Subacute exposure of mice to the ICG did not change significantly the hematological and biochemical parameters as well as histology of organs. The ICG increased the duration of estrous cycle in all phases, showing anti-inflammatory potential by decreasing leukocyte migration, extravasation protein in the pleural cavity and antiedematogenic activity. The ICG treatment at a dose of 700 mg/kg decreased the mechanical hyperalgesia, while at doses of 300 mg/kg and 700 mg/kg, decreased the sensitivity to the cold.

CONCLUSION

The results evidenced the anti-inflammatory potential with low toxicity of infusion of the leaves of C. guazumifolia, supporting the popular use of this species.

Photoprotective Substances Derived from Marine Algae

Marine algae have received great attention as natural photoprotective agents due to their unique and exclusive bioactive substances which have been acquired as an adaptation to the extreme marine environment combine with a range of physical parameters. These photoprotective substances include mycosporine-like amino acids (MAAs), sulfated polysaccharides, carotenoids, and polyphenols. Marine algal photoprotective substances exhibit a wide range of biological activities such as ultraviolet (UV) absorbing, antioxidant, matrix-metalloproteinase inhibitors, anti-aging, and immunomodulatory activities. Hence, such unique bioactive substances derived from marine algae have been regarded as having potential for use in skin care, cosmetics, and pharmaceutical products. In this context, this contribution aims at revealing bioactive substances found in marine algae, outlines their photoprotective potential, and provides an overview of developments of blue biotechnology to obtain photoprotective substances and their prospective applications.