Topical Antiedematogenic Activity of the Essential Oil of Psidium brownianum Mart. (OEPB) in Murine Ear Edema Models.

Psidium brownianum Mart is reported in the literature by antinociceptive and antioxidant activities, indicating that this species' secondary metabolites might be used to control inflammatory processes. The present study aimed to characterize the topical antiedematogenic activity of the essential oil of Psidium brownianum Mart. (OEPB) in ear edema models by different inflammatory agents. Female Swiss mice (25-35 g) and Wistar albino rats (200-300 g) were used throughout tests (n=6/group) on acute or chronic edema models induced by single and multiple topical applications. The OEPB is administered topically pure or at a concentration of 100 or 200 mg/mL. The antiedematogenic mechanism of OEPB was analyzed by administering capsaicin, arachidonic acid, histamine, and phenol at the best effective dose (200 mg/mL). The results showed a significant reduction of edema-induced single (28.87 %) and multiple (50.13 %) applications of croton oil compared to the negative control group. Regarding potential mechanisms of action, OEPB (200 mg/mL) inhibited the development of edema triggered by capsaicin (29.95 %), arachidonic acid (22.66 %), phenol (23.35 %), and histamine (75.46 %), suggesting an interference with the histaminergic pathway. These results indicate that OEPB presents a topical antiedematogenic effect in acute and chronic murine models, possibly interfering with inflammatory pathways triggered by mediators such as histamine.

In vitro and in silico antibacterial evaluation of coumarin derivatives against MDR strains of Staphylococcus aureus and Escherichia coli.

The increase in antibiotic resistance rates has attracted the interest of researchers for antibacterial compounds capable of potentiating the activity of conventional antibiotics. Coumarin derivatives have been reported to develop effective antibacterials with possible new mechanisms of action for treating infectious diseases caused by bacteria with a profile of drug resistance. In this context, the aim of the present study we have now prepared one variety of new synthetic coumarins evaluating the pharmacokinetic and chemical similarity in silico, their antimicrobial activity against Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922), and potential for the modulation of antibiotic resistance against Staphylococcus aureus (SA10) and Escherichia coli (EC06) clinical isolate bacteria by in vitro assay. The antibacterial activity and antibiotic-enhancing properties were evaluated by the broth microdilution method and pharmacokinetically characterized according to the Lipinsk rule of 5 and had their similarity analyzed in databases such as ChemBL and CAS SciFinder. The results demonstrated that only compound C13 showed significant antibacterial activity (MIC ≤256 µg/mL), and all other coumarins did not display relevant antibacterial activity (MIC ≥1024 µg/mL). However, they did modulate the antibiotics activities to norfloxacin and gentamicin, except, compound C11 to norfloxacin against Staphylococcus aureus (SA10). The in silico properties prediction and drug-likeness results demonstrated that all coumarins presented a good drug-likeness score with no violations and promising in silico pharmacokinetic profiles showing that they have the potential to be developed into an oral drug. The results indicate that the coumarin derivatives showed good in vitro antibacterial activity. These new coumarin derivatives also demonstrated the capacity to modulate antibiotic resistance with potential synergy action for current antimicrobials assayed, as antibiotic adjuvants, to reduce the emergence of antimicrobial resistance.

In vitro and in silico evidences about the inhibition of MepA efflux pump by coumarin derivatives.

The discovery of antibiotics has significantly transformed the outcomes of bacterial infections in the last decades. However, the development of antibiotic resistance mechanisms has allowed an increasing number of bacterial strains to overcome the action of antibiotics, decreasing their effectiveness against infections they were developed to treat. This study aimed to evaluate the antibacterial activity of synthetic coumarins Staphylococcus aureus in vitro and analyze their interaction with the MepA efflux pump in silico. The Minimum Inhibitory Concentration (MIC) determination showed that none of the test compounds have antibacterial activity. However, all coumarin derivatives decreased the MIC of the standard efflux inhibitor ethidium bromide, indicating antibacterial synergism. On the other hand, the C14 derivative potentiated the antibacterial activity of ciprofloxacin against the resistant strain. In silico analysis showed that C9, C11, and C13 coumarins showed the most favorable interaction with the MepA efflux pump. Nevertheless, due to the present in silico and in vitro investigation limitations, further experimental research is required to confirm the therapeutic potential of these compounds in vivo.

Antiedematogenic and Analgesic Activities of Abietic Acid in Mice.

Exacerbated inflammatory responses to harmful stimuli can lead to significant pain, edema, and other complications that require pharmacological intervention. Abietic acid (AA) is a diterpene found as a significant constituent in pine species, and evidence has identified its biological potential. The present study aimed to evaluate abietic acid's antiedematogenic and anti-inflammatory activity in mice. Swiss mice (Mus musculus) weighing 20-30 g were treated with AA at 50, 100, and 200 mg/kg. The central nervous system (CNS) effects were evaluated using open-field and rotarod assays. The antinociceptive and anti-inflammatory screening was assessed by the acetic acid and formalin tests. The antiedematogenic activity was investigated by measuring paw edema induced by carrageenan, dextran, histamine, arachidonic acid, and prostaglandin, in addition to using a granuloma model. The oral administration of abietic acid (200 mg/Kg) showed no evidence of CNS effects. The compound also exhibited significant antiedematogenic and anti-inflammatory activities in the carrageenan and dextran models, mostly related to the inhibition of myeloperoxidase (MOP) activity and histamine action and, to a lesser extent, the inhibition of eicosanoid-dependent pathways. In the granuloma model, abietic acid's effect was less expressive than in the acute models investigated in this study. In conclusion, abietic acid has analgesic and antiedematogenic activities related to anti-inflammatory mechanisms.

Plectranthus Species with Anti-Inflammatory and Analgesic Potential: A Systematic Review on Ethnobotanical and Pharmacological Findings.

The use of medicinal plants to treat inflammatory conditions and painful processes has attracted the attention of scientists and health professionals due to the evidence that natural products can promote significant therapeutic benefits associated with fewer adverse effects compared to conventional anti-inflammatory drugs. The genus Plectranthus is composed of various plants with pharmacological potential, which are used to treat various diseases in traditional communities worldwide. The present study systematically reviewed Plectranthus species with anti-inflammatory and analgesic potential. To this end, a systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. The search was conducted on the following databases: PubMed, ScienceDirect, SciVerse Scopus, and Web of Science. Different combinations of search terms were used to ensure more excellent article coverage. After the selection, a total of 45 articles were included in this review. This study identified twelve Plectranthus species indicated for the treatment of different inflammatory conditions, such as wounds, fever, bronchitis, abscess, asthma, hepatitis, labyrinthitis, tonsillitis, and uterine inflammation. The indications for pain conditions included headache, sore throat, heartburn, menstrual cramp, colic, toothache, stomachache, migraine, chest pain, abdominal pain, local pain, labor pain, and recurring pain. Among the listed species, ten plants were found to be used according to traditional knowledge, although only four of them have been experimentally studied. When assessing the methodological quality of preclinical in vivo assays, most items presented a risk of bias. The SR results revealed the existence of different Plectranthus species used to treat inflammation and pain. The results of this systematic review indicate that Plectranthus species have the potential to be used in the treatment of diseases with an inflammatory component, as well as in the management of pain. However, given the risk of biases, the experimental analysis of these species through preclinical testing is crucial for their safe and effective use.

Efflux Pump (QacA, QacB, and QacC) and ß-Lactamase Inhibitors? An Evaluation of 1,8-Naphthyridines against Staphylococcus aureus Strains.

The bacterial species Staphylococcus aureus presents a variety of resistance mechanisms, among which the expression of ß-lactamases and efflux pumps stand out for providing a significant degree of resistance to clinically relevant antibiotics. The 1,8-naphthyridines are nitrogen heterocycles with a broad spectrum of biological activities and, as such, are promising research targets. However, the potential roles of these compounds on bacterial resistance management remain to be better investigated. Therefore, the present study evaluated the antibacterial activity of 1,8-naphthyridine sulfonamides, addressing their ability to act as inhibitors of ß-lactamases and efflux pump (QacA/B and QacC) against the strains SA-K4414 and SA-K4100 of S. aureus. All substances were prepared at an initial concentration of 1024 µg/mL, and their minimum inhibitory concentrations (MIC) were determined by the broth microdilution method. Subsequently, their effects on ß-lactamase- and efflux pump-mediated antibiotic resistance was evaluated from the reduction of the MIC of ethidium bromide (EtBr) and ß-lactam antibiotics, respectively. The 1,8-naphthyridines did not present direct antibacterial activity against the strains SA-K4414 and SA-K4100 of S. aureus. On the other hand, when associated with antibiotics against both strains, the compounds reduced the MIC of EtBr and ß-lactam antibiotics, suggesting that they may act by inhibiting ß-lactamases and efflux pumps such as QacC and QacA/B. However, further research is required to elucidate the molecular mechanisms underlying these observed effects.

In Vitro and In Silico Inhibition of Staphylococcus aureus Efflux Pump NorA by α-Pinene and Limonene.

Since the discovery of the first antibiotics, bacteria have acquired a variety of resistance mechanisms, with efflux pump (EP) being the most prominent mechanism for intracellular targeting drugs. These proteins have become efficient mechanisms of resistance to antibiotics in species such as Staphylococcus aureus and, therefore, have been identified as promising therapeutic targets in antibacterial drug development. Accordingly, evidence suggests that monoterpenes can act as EP inhibitors and can be useful in circumventing bacterial resistance. This study aimed to evaluate the effectiveness of monoterpenes α-pinene and limonene as EP inhibitors against a strain of S. aureus expressing NorA protein. The minimum inhibitory concentration (MIC) against the 1199B strain of S. aureus, which carries genes encoding efflux proteins associated with antibiotic resistance to norfloxacin, was assessed through the broth microdilution method. The results obtained served as a subsidy for the analysis of the NorA pump inhibition with norfloxacin and ethidium bromide. Docking techniques, in silico, were used to evaluate the interaction of monoterpenes with NorA. Both monoterpenes showed no clinically effective antibacterial activity. Nevertheless, these compounds were found to decrease the MICs of ethidium bromide and norfloxacin indicating EP inhibition, which was confirmed by molecular docking analyses. In conclusion, α-pinene and limonene showed promising antibiotic-enhancing properties in S. aureus 1199B strain, indicating that monoterpenes can be used in targeted drug development to combat antibiotic resistance associated with EP expression.

Enhancement of Antibiotic Activity by 1,8-Naphthyridine Derivatives against Multi-Resistant Bacterial Strains.

The search for new antibacterial agents has become urgent due to the exponential growth of bacterial resistance to antibiotics. Nitrogen-containing heterocycles such as 1,8-naphthyridine derivatives have been shown to have excellent antimicrobial properties. Therefore, the purpose of this study was to evaluate the antibacterial and antibiotic-modulating activities of 1,8-naphthyridine derivatives against multi-resistant bacterial strains. The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of the following compounds: 7-acetamido-1,8-naphthyridin-4(1H)-one and 3-trifluoromethyl-N-(5-chloro-1,8-naphthyridin-2-yl)-benzenesulfonamide. The antibiotic-modulating activity was analyzed using subinhibitory concentrations (MIC/8) of these compounds in combination with norfloxacin, ofloxacin, and lomefloxacin. Multi-resistant strains of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus were used in both tests. Although the compounds had no direct antibacterial activity (MIC ≥ 1.024 µg/mL), they could decrease the MIC of these fluoroquinolones, indicating synergism was obtained from the association of the compounds. These results suggest the existence of a structure-activity relationship in this group of compounds with regard to the modulation of antibiotic activity. Therefore, we conclude that 1,8-naphthyridine derivatives potentiate the activity of fluoroquinolone antibiotics against multi-resistant bacterial strains, and thereby interesting candidates for the development of drugs against bacterial infections caused by multidrug resistant strains.

Potentiation of Antibiotic Activity by a Meldrum's Acid Arylamino Methylene Derivative against Multidrug-Resistant Bacterial Strains.

This study aimed to evaluate the intrinsic antibacterial activity and antibiotic-enhancing effect of an arylamino methylene derivative (MAD) in association with fluoroquinolones. The antibacterial activity against multiresistant Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli was analyzed by determining the minimum inhibitory concentration (MIC) using the broth micro dilution method. A reduction in the MIC of the fluoroquinolones against strains treated simultaneously with the MAD was interpreted as an enhanced antibiotic activity. While the MAD exhibited no clinically effective action (MIC ≥ 1.024 µg/mL), it was found to significantly potentiate the activity of norfloxacin, ofloxacin and lomefloxacin against all the strains, which may be related to structural similarities between the MAD and quinolones. Our findings suggest that Meldrum's acid arylamino derivatives may represent promising molecules in the elaboration of new drugs to reverse resistance to fluoroquinolones.

Characterization and antibacterial activity of the essential oil obtained from the leaves of Baccharis coridifolia DC against multiresistant strains.

Essential oils are secondary metabolites with immense pharmacological potential.These substances are abundantly produced by plants of the family Asteraceae, such as Baccharis coridifolia. Previous studies have demonstrated that this species has pharmacological properties that make it a promising source of new antibacterial agents. Therefore, the present study aimed to evaluate the antibacterial and antibiotic-modulating activity of Baccharis coridifolia essential oil against multidrug-resistant (MDR) strains. The phytochemical analysis was carried out by gas chromatography coupled to Mass Spectroscopy (GC/MS), and realized the Minimum Inhibitory Concentation (MIC) and antibiotic-modulation from the microdilution method in 96-well plates. It was revealed the presence of germacrene D (23.7%), bicyclogermacrene (17.1%), and (E)-caryophyllene (8.4%) as major components. The minimum inhibitory concentration of essential oil against strains of Pseudomonas aeruginosa (512 µg/mL) and Staphylococcus aureus (128 µg/mL) demonstrated clinically relevant antibacterial activity. In addition, the combination of subinhibitory doses of the oil with conventional antibiotics showed synergism, indicating potentiation of the antibacterial effect. In conclusion, the essential oil of Baccharis coridifolia (EOBc) presented antibacterial and antibiotic-modulating activities that place this species as a source of molecules useful in the fight against bacterial resistance.

Carvone Enantiomers Differentially Modulate IgE-Mediated Airway Inflammation in Mice.

Carvone is a monoterpene found in nature in the form of enantiomers (S- and R-). While previous research has demonstrated the anti-inflammatory and anti-allergic effects of carvone, the influence of carvone enantiomeric composition on its anti-allergic activity remains to be investigated. This study aimed to evaluate the anti-allergic activity of carvone enantiomers in a murine model of airway allergic inflammation induced by sensitization and challenge with ovalbumin (OVA). The oral treatment with R-carvone or S-carvone 1 h before each challenge inhibited the number of leukocytes and eosinophils in the bronchoalveolar lavage (BAL). R-carvone inhibited leukocyte infiltration and mucus production in the lung, which was correlated with decreased production of OVA-specific IgE in the serum and increased concentrations of IL-10 in the BAL. On the other hand, the administration of S-carvone had little inhibitory effect on inflammatory infiltration and mucus production in the lung, which might be associated with increased production of IFN-γ in the BAL. When administered 1 h before each sensitization, both enantiomers inhibited eosinophil recruitment to the BAL but failed in decreasing the titers of IgE in the serum of allergic mice. Our data indicate that carvone enantiomers differentially modulated IgE-mediated airway inflammation in mice. In conclusion, unlike S-carvone, R-carvone has the potential to be used in anti-allergic drug development.

Nootkatone Inhibits Acute and Chronic Inflammatory Responses in Mice.

Nootkatone (NTK) is a sesquiterpenoid found in essential oils of many species of Citrus (Rutaceae). Considering previous reports demonstrating that NTK inhibited inflammatory signaling pathways, this study aimed to investigate the effects of this compound in mice models of acute and chronic inflammation. Murine models of paw edema induced by carrageenan, dextran, histamine, and arachidonic acid, as well as carrageenan-induced peritonitis and pleurisy, were used to evaluate the effects of NTK on acute inflammation. A murine model of granuloma induced by cotton pellets was used to access the impact of NTK treatment on chronic inflammation. In the acute inflammation models, NTK demonstrated antiedematogenic effects and inhibited leukocyte recruitment, which was associated with decreased vascular permeability, inhibition of myeloperoxidase (MPO), interleukin (IL)1-ß, and tumor necrosis factor (TNF)-α production. In silico analysis suggest that NTZ anti-inflammatory effects may also occur due to inhibition of cyclooxygenase (COX)-2 activity and antagonism of the histamine receptor type 1 (H1). These mechanisms might have contributed to the reduction of granuloma weight and protein concentration in the homogenates, observed in the chronic inflammation model. In conclusion, NTK exerted anti-inflammatory effects that are associated with inhibition of IL1-ß and TNF-α production, possibly due to inhibition of COX-2 activity and antagonism of the H1 receptor. However, further studies are required to characterize the effects of this compound on chronic inflammation.

New roles of fluoxetine in pharmacology: Antibacterial effect and modulation of antibiotic activity.

The antimicrobial activity of psychotropic drugs, especially those of the class of mainly phenothiazines has been previously reported. Other drugs, including verapamil and trifluoperazine demonstrated to be effective against multidrug-resistant strains. Selective serotonin reuptake inhibitors (SSRIs) are antidepressant drugs that have presented significant activity against resistant bacterial resistance, but the antibacterial effect as well the antibiotic modulating properties of fluoxetine remain to be elucidated. Therefore, the present study aimed to evaluate in vitro, the antibacterial effect and the antibiotic modulating activity of fluoxetine against standard and multiresistant bacterial strains. The microorganisms used were Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli. For the antibacterial tests, 10 mg fluoxetine hydrochloride were and diluted in 1 mL of dimethyl sulfoxide (DMSO) and then diluted in sterile distilled water to a concentration of 1024 µg/mL. To determine the Minimum Inhibitory Concentrations (MICs), the drugs were diluted to concentrations ranging from 512 to 0.5 µg/mL in 96-well microdilution plates. The evaluation of the modulatory activity of fluoxetine was performed by combining this drug with the following antibiotics: Erythromycin, Gentamicin, Imipenem, Norfloxacin and Tetracycline at subinhibitory concentrations (MIC/8). Our results demonstrated that the MIC fluoxetine were 256 and 102 µg/mL against standard and resistant strains of S. aureus, respectively. The MIC of fluoxetine against both standard and resistant strains of P. aeruginosa was 161 µg/mL and against E. coli, the MIC of fluoxetine was 102 µg/mL for both standard and resistant strains, demonstrating that this drug present significant antibacterial activity. The association of fluoxetine with gentamicin and erythromycin P. aeruginosa and E. coli presented synergistic effects, demonstrating that this drug can selectively modulate the activity of antibiotics of clinical use. In conclusion, fluoxetine presented significant antibacterial effect and potential antibiotic modulating activity against multiresistant bacteria. Therefore, additional studies are needed to characterize the antimicrobial properties of this drug, as well as the clinical implications of its use in the treatment of infections by resistant microorganisms.

Vanillin selectively modulates the action of antibiotics against resistant bacteria.

The treatment of infections caused by microorganisms that are resistant to antibiotics represent one of the main challenges of medicine today, especially due to the inefficacy of long-term drug therapy. In the search for new alternatives to treat these infections, many researchers have been looking for new substances derived from natural products to replace, or be used in combination with conventional antibiotics. Vanillin is a phenolic compound whose antimicrobial activity has been used in the elimination of pathogens present in fruits and vegetables. However, its antibacterial and modulating properties remain to be characterized. Therefore, this work aimed to evaluate the antibacterial activity and analyze the modulator activity of vanillin in association with conventional antibiotics. The antimicrobial activity of vanillin was evaluated using the microdilution method to determine the Minimum Inhibitory Concentration (MIC) Standard strains of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and multi-resistant strains of Escherichia coli 06, Staphylococcus aureus 10, Pseudomonas aeruginosa 24 were used in this study. The antibiotic modulating effect was analyzed by combining vanillin with Norfloxacin, Imipenem, Gentamicin, Erythromycin and Tetracycline against the following multiresistant bacteria strains: Escherichia coli 06, Staphylococcus aureus 10 and Pseudomonas aeruginosa 24. Data were analyzed using the ANOVA test of two tracks followed by the post hoc Bonferroni test. Vanillin presented CIMs ≥1024µg/mL against all tested strains demonstrating that it did not present significant antibacterial activity. However, modulated the activity of gentamicin and imipenem against S. aureus and E. coli, causing a synergistic effect, but did not affect the activity of norfloxacin, tetracycline and erythromycin against these same microorganisms. A synergistic effect was also obtained from the association of vanillin with norfloxacin against P. aeruginosa. On the other hand, against this strain the association of vanillin with tetracycline and erythromycin caused antagonism, although the activity of gentamicin and imipenem was not affected. In conclusion, vanillin selectively modulated the activity of antibiotics against multiresistant bacteria and as such, might be useful in the development of new therapies against resistant microorganism.

Psidium guajava L. and Psidium brownianum Mart ex DC.: Chemical composition and anti - Candida effect in association with fluconazole.

The therapeutic combinations have been increasingly used against fungal resistance. Natural products have been evaluated in combination with pharmaceutical drugs in the search for new components able to work together in order to neutralize the multiple resistance mechanisms found in yeasts from the genus Candida. The aqueous and hydroethanolic extracts from Psidium brownianum Mart ex DC. and Psidium guajava L. species were evaluated for their potential to change the effect of commercial pharmaceutical drugs against Candida albicans and Candida tropicalis strains. The tests were performed according to the broth microdilution method. Plate readings were carried out by spectrophotometry, and the data generated the cell viability curve and IC50 of the extracts against the yeasts. A chemical analysis of all the extracts was performed for detection and characterization of the secondary metabolites. The total phenols were quantified in gallic acid eq/g of extract (GAE/g) and the phenolic composition of the extracts was determined by HPLC. Fluconazole and all extracts presented high Minimum Inhibitories Concentrations (MICs). However, when associated with the extracts at sub-inhibitory concentrations (MIC/16), fluconazole had its effect potentiated. A synergistic effect was observed in the combination of fluconazole with Psidium brownianum extracts against all Candida strains. However, for Psidium guajava extracts the synergistic effect was produced mainly against the Candida albicans LM77 and Candida tropicalis INCQS 400042 strains. The IC50 values of fluconazole ranged from 19.22 to 68.1 µg/mL when it was used alone, but from 2.2 to 45.4 µg/mL in the presence of the extracts. The qualitative chemical characterization demonstrated the presence of phenols, flavonoids and tannins among the secondary metabolites. The concentration of total phenols ranged from 49.25 to 80.77 GAE/g in the P. brownianum extracts and from 68.06 to 82.18 GAE/g in the P. guajava extracts. Our results indicated that both P. brownianum and P. guajava extracts are effective on potentiating the effect of fluconazole, and therefore, these plants have the potential for development of new effective drugs for treating fungal infections.

Anti-allergic properties of curine, a bisbenzylisoquinoline alkaloid.

Curine is a bisbenzylisoquinoline alkaloid isolated from Chondrodendron platyphyllum (Menispermaceae). Recent findings have shed light on the actions of curine in different models of allergy and inflammation. Here we review the properties and mechanisms of action of curine focusing on its anti-allergic effects. Curine pre-treatment significantly inhibited the scratching behavior, paw edema and systemic anaphylaxis induced by either ovalbumin (OVA) in sensitized animals or compound 48/80, through mechanisms of mast cell stabilization and inhibition of mast cell activation to generate lipid mediators. In addition, oral administration of curine significantly inhibited eosinophil recruitment and activation, as well as, OVA-induced airway hyper-responsiveness in a mouse model of asthma, through inhibition of the production of IL-13 and eotaxin, and of Ca2+ influx. In conclusion, curine exhibit anti-allergic effects in models of lung, skin and systemic allergy in the absence of significant toxicity, and as such has the potential for anti-allergic drug development.

Curine, an alkaloid isolated from Chondrodendron platyphyllum inhibits prostaglandin E2 in experimental models of inflammation and pain.

Curine is a bisbenzylisoquinoline alkaloid that is isolated from Chondrodendron platyphyllum, a plant that is used to treat malaria, inflammation, and pain. Recent reports have demonstrated the antiallergic effects of curine at nontoxic doses. However, its anti-inflammatory and analgesic properties remain to be elucidated. This study investigated the anti-inflammatory and analgesic effects of curine in mice. We analyzed the effects of an oral treatment with curine in the formation of paw edema, vascular permeability, abdominal contortion, licking behavior, and hyperalgesia using different inflammatory stimuli. Curine significantly inhibited the formation of paw edema by decreasing vascular permeability, inhibited the acetic acid-induced writhing response, inhibited the licking behavior during inflammation but not during the neurogenic phase of the formalin test, and inhibited carrageenan-induced hyperalgesia. Finally, curine inhibited prostaglandin E2 production in vitro without affecting cyclooxygenase-2 expression. The effects of curine treatment were similar to the effects of indomethacin, but were different from the effects of morphine treatment, suggesting that the analgesic effects of curine do not result from the direct inhibition of neuronal activation but instead depend on anti-inflammatory mechanisms that, at least in part, result from the inhibition of prostaglandin E2 production. In conclusion, curine presents anti-inflammatory and analgesic effects at nontoxic doses and has the potential for use in anti-inflammatory drug development.

Pharmacological potential of limonene against opportunistic fungi: Impact on Candida virulence.

The present article aims to evaluate the antifungal and antivirulence effect of the phytoconstituent Limonene against Candida spp. Antifungal assays were performed, where the concentration capable of inhibiting 50 % of fungal growth, the growth inhibition curve, the minimum fungicidal concentration, the evaluation of the modifying effect with fluconazole, the inhibitory effect of the substances on the morphological transition of Candida spp. and the statistical analysis of the results were determined. With this study, it was seen that limonene demonstrated growth inhibition for the strains tested and when associated the natural compound with Fluconazole, there was potentiation of the effect of the drug, since the inhibition of growth by the combination occurred at lower concentrations against all strains tested, when compared to the drug alone, which inhibited growth at the highest concentration. In the test to determine the Minimum Fungicidal Concentration of the products tested alone and in combination, it was found that in the case of Candida strains, growth inhibition by limonene occurred at a concentration of 1024 µg/mL. For Fluconazole, growth impairment ranged from > 1024 µg/mL to 256 µg/mL for the strains. And when combined, limonene potentiated the action of FCZ, making fungal colonization unfeasible at concentrations below 1024 µg/mL. Regarding the morphological transition from yeast to hyphae, limonene was used at concentrations of 1024 µg/mL and 512 µg/mL, and it was found that, for CA and CK, the filaments were reduced in number and size at the highest concentration and against CT, the morphological transition from yeast to hyphae/pseudohyphae was totally inhibited, and if compared to the growth control, limonene was able to reduce fungal growth at concentrations greater than 512 µg/mL. This compound has antimicrobial activity described, due to its ability to interfere in the gene expression of the fungus, the limited therapeutic options and the recent emergence of multidrug-resistant Candida species represent a significant challenge for human medicine and highlight the need for new therapeutic approaches, and in this study a great potential of limonene was revealed in relation to the perspective of increasing the efficiency of commercial drug. This work can bring an important contribution to the scientific database, while emphasizing that in-depth studies and tests on the subject, in order to better investigate its effectiveness and mechanisms by which they exert their effects, are still necessary.

Assessing dental surgeons' understanding of bisphosphonates: Implications for patient health in oral surgery.

Objectives: This study aimed to analyze the knowledge of dental surgeons concerning the pharmacological effects of bisphosphonates (BP) and their impact on the health of patients undergoing oral surgery treatment. Materials and methods: A quantitative study was conducted with professionals in the Cariri region of Ceará, Brazil. The data were collected using a semi-structured questionnaire to interview the dental surgeons who met the inclusion criteria. The data were analyzed by Chi-square and Fischer's Exact tests using the SPSS program version 22.0. Results: The results indicated that most interviewed subjects have no experience with the dental treatment of individuals under treatment with bisphosphonates. When a sample of the medication was presented, a significant number of the participants (65.3%) did not recognize the drug. Among those who recognized it, 66.5% did not know how to treat bisphosphonate-using patients in the clinical routine. However, 95.1% of the professionals who recognized the need to discontinue these drugs admitted contacting the prescriber to establish the best dental conduct. Our results also showed that recently graduated professionals better understood the need to stop BP use before invasive treatment, although they did not know the protocol. Conclusion: In conclusion, a better knowledge of the pharmacological effects of BP is crucial for conducting adequate anamnesis, requesting additional tests, and performing medical monitoring, which has a significant impact on the clinical practice of dental surgeons.

Liposomal formulation with thiazolic compounds against bacterial efflux pumps.

This study aimed to evaluate the effects of liposome-encapsulated eugenol-based thiazolic derivatives against efflux pump-carrying bacteria. The Minimum Inhibitory Concentration (MIC) was determined to evaluate the antibacterial activity and antibiotic potentiation against Pseudomonas aeruginosa and Staphylococcus aureus, as well as to analyze the inhibition of efflux pumps in S. aureus strains 1199B and K2068 in the ethidium bromide assay. The direct antibacterial activity analysis showed no clinically relevant results since the compounds presented MICs ≥1024 µg/mL. Regarding the analysis of antibiotic potentiation against multidrug-resistant (MDR) strains of S. aureus, compound LF16 reduced norfloxacin MIC from 128 µg/mL to 64 µg/mL. All associated with gentamicin caused a significant antibiotic MIC reduction. None of the compounds could potentate the activity of norfloxacin against P. aeruginosa. However, all of them potentiated the activity of gentamicin against the same strain. Only the LF 26 caused a significant MIC reduction in the ethidium bromide assay, suggesting efflux inhibition in the S. aureus 1199B strain. Similar results were observed with the K2068 strain. Observing antibiotic MIC reduction S. aureus strains carrying the NorA and MepA proteins brought additional evidence of efflux pump inhibition. Our results indicate that while eugenol-based thiazoles didn't exhibit direct activity, they can potentiate the antibiotics activity against MDR strains of P. aeruginosa and S. aureus. Among them, compound LF 26 potentiated the inhibitory effects of ethidium bromide and antibiotics against S. aureus strains carrying the NorA and MepA proteins, indicating a potential role of this class of compounds as efflux pump inhibitors.