Analytical techniques to recognize inclusion complexes formation involving monoterpenes and cyclodextrins: A study case with (-) borneol, a food ingredient

Monoterpenes are non-polar secondary metabolites widely used by industry due to their excellent therapeutic, food-ingredient and cosmetic properties. However, their low solubility in water limits their use. In this sense, cyclodextrins (CDs) have been widely used to solve these technological challenges. Thus, this study aims to use (-)-borneol as a monoterpene model to prepare inclusion complexes between β-CD and hydroxypropyl-β-CD (HP-β-CD) through different ways and characterize them in order to choose the best inclusion method to improve physicochemical properties of monoterpenes. To achieve this goal, the samples were prepared by physical mixture (PM), paste complex (PA) and freeze-drying complex (FD) and then, extensively characterized by thermal analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy, size particle, X-ray diffraction and nuclear magnetic resonance. The physicochemical results showed that freeze-drying was more effective to form inclusion complexes between (-)-borneol with both CDs. This research highlights the importance of recognizing the best method to prepare inclusion complexes, including food additives as (-)-borneol, to achieve better results in food preparations.

Antihypertensive effect of carvacrol is improved after incorporation in β-cyclodextrin as a drug delivery system

Carvacrol (CARV), has been shown to possess various pharmacological properties, especially in the treatment of cardiovascular diseases. We evaluated the antihypertensive effect of the CARV free and encapsulation of CARV in β-cyclodextrin (CARV/β-CD), and whether CARV/β-CD is able to improve the antihypertensive effects of CARV free in spontaneously hypertensive rats (SHR). The rats were randomly divided into four groups, each treated daily for 21 days and the mean arterial pressure and heart rate was measured every 5 days: group 1, Wistar-vehicle solution; group 2, SHR-vehicle; group 3, SHR-CARV 50 mg/kg/d; and group 4, CARV/β-CD 50 mg/kg/d. After 21 days of treatment, the mesenteric artery from treated animals was tested for phenylephrine (Phe) and sodium nitroprusside (SNP) sensitivity. In addition, administration of CARV/β-CD induced important antihypertensive activity when compared with the uncomplexed form, reducing the progression of arterial hypertension in SHR. Moreover, pharmacological potency to Phe in the SHR-CARV and CARV/β-CD groups was increased, approaching values expressed in the Wistar-vehicle. Furthermore, CARV/β-CD reduced the production of the pro-inflammatory mediator, IL-1β, and increased anti-inflammatory cytokine, IL-10. Together, these results produced evidence that the encapsulation of CARV in β-CD can improve cardiovascular activity, showing potential anti-inflammatory and antihypertensive effects.

(-)-linalool-Loaded Polymeric Nanocapsules Are a Potential Candidate to Fibromyalgia Treatment

Fibromyalgia (FM) is a chronic disease that has as main characteristic generalized musculoskeletal pain, which can cause physical and emotional problems to patients. However, pharmacological therapies show side effects that hamper the adhesion to treatment. Given this, (-)-linalool (LIN), a monoterpene with several therapeutic properties already reported in scientific literature as anti-depressive, antinociceptive, anti-inflammatory, and antihyperalgesic also demonstrated therapeutic potential in the treatment of FM. Nevertheless, physicochemical limitations as high volatilization and poor water-solubility make its use difficult. In this perspective, this present research had performed the incorporation of LIN into polymeric nanocapsules (LIN-NC). Size, morphology, encapsulation efficiency, cytotoxicity, and drug release were performed. The antihyperalgesic effect of LIN-NC was evaluated by a chronic non-inflammatory muscle pain model. The results demonstrated that the polymeric nanocapsules showed particle size of 199.1 ± 0.7 nm with a PDI measurement of 0.13 ± 0.01. The drug content and encapsulation efficiency were 13.78 ± 0.05 mg/mL and 80.98 ± 0.003%, respectively. The formulation did not show cytotoxicity on J774 macrophages. The oral treatment with LIN-NC and free-LIN increased the mechanical withdrawal threshold on all days of treatment in comparison with the control group. In conclusion, LIN-NC is a promising proposal in the development of phytotherapy-based nanoformulations for future clinical applications.

SARS, MERS and SARS-CoV-2 (COVID-19) treatment: a patent review

INTRODUCTION

Coronavirus has been responsible for several virus outbreaks since 2003, caused by SARS-CoV-1, MERS-CoV, and currently SARS-CoV-2 (COVID-19), the causative agent of coronavirus disease in 2019. COVID-19 has become a global public health emergency because of its high virulence and mortality capacity. This patent review aims to provide an overview of the patents that present possible treatments for SARS-CoV-1, SARS-CoV-2 and MERS-CoV.

AREAS COVERED

To treat SARS, MERS and SARS-CoV-2, researchers have filed patents for a number of therapeutic agents. Most of the treatments found were protease inhibitors aimed at proteases such as PLpro, 3 CLpro, RNA helicase, and Spike protein, or used monoclonal antibodies and interferons. In addition, the use of Chinese folk medicine and its multitude of medicinal plants with strong antiviral properties was reinforced. Thus, these therapies used in previous epidemics can serve as an aid in the new pandemic by SARS-CoV-2 and be a starting point for new treatments.

EXPERT OPINION

The various antiviral alternatives presented in this review offer therapeutic options to fight coronavirus infections. If shown to be effective, these drugs may be extremely important in the current pandemic.

Characterization of β-cyclodextrin/myrtenol complex and its protective effect against nociceptive behavior and cognitive impairment in a chronic musculoskeletal pain model

Myrtenol has gained wide interest because of its pharmacological profiles, mainly for treatment of chronic diseases. To improve the solubility of myrtenol, the formation of inclusion complexes with β-cyclodextrin was performed by physical mixture, kneading process or slurry complexation (SC) methods and characterized using thermal analysis, XRD, SEM and NMR. From these results, myrtenol complexed by SC was successfully complexed into β-cyclodextrin cavity. The interaction between myrtenol and β-cyclodextrin was confirmed by molecular docking. Hence, the SC β-cyclodextrin-myrtenol complex was evaluate for its anti-hyperalgesic, anxiolytic and antioxidant activity in a fibromyalgia model. Results show that myrtenol and β-cyclodextrin form a stable complex and have anti-hyperalgesic effect, improve the cognitive impairment caused and have an anxiolytic-like effect. Furthermore, the β-cyclodextrin/myrtenol complex decrease lipoperoxidation, increased catalase activity and a reduce SOD/CAT ratio. Therefore, β-cyclodextrin/myrtenol complex reduce painful behavior, improves motor skills and emotional behavior and decreases oxidative stress in a fibromyalgia model.

NOX-dependent reactive oxygen species production underlies arrhythmias susceptibility in dexamethasone-treated rats

Dexamethasone is the most clinically used glucocorticoid with an established role in the treatment of a wide spectrum of inflammatory-related diseases. While the therapeutic actions are well known, dexamethasone treatment causes a number of cardiovascular side effects, which are complex, frequent and, in some cases, clinically unnoticeable. Here, we investigated whether a therapeutic regimen of dexamethasone affects cardiac arrhythmogenesis, focusing on the contribution of Nox-derived reactive oxygen species (ROS). Male Wistar rats were treated with dexamethasone (2 mg/kg, i.p.) for 7 days. Afterward, hemodynamic measurements, autonomic modulation, left ventricular function, cardiac fibrosis, reactive oxygen species (ROS) generation, Nox protein expression, superoxide dismutase (SOD) and catalase activities, and arrhythmias incidence were evaluated. Here, we show that dexamethasone increases blood pressure, associated with enhanced cardiac and vascular sympathetic modulation. Moreover, a marked increase in the cardiac ROS generation was observed, whereas the enhanced SOD activity did not prevent the higher levels of lipid peroxidation in the dexamethasone group. On the other hand, increased cardiac Nox 4 expression and hydrogen peroxide decomposition rate was observed in dexamethasone-treated rats, while Nox 2 remained unchanged. Interestingly, although preserved ventricular contractility and β-adrenergic responsiveness, we found that dexamethasone-treated rats displayed greater interstitial and perivascular fibrosis than control. Surprisingly, despite the absence of arrhythmias at basal condition, we demonstrated, by in vivo and ex vivo approaches, that dexamethasone-treated rats are more susceptible to develop harmful forms of ventricular arrhythmias when challenged with pharmacological drugs or burst pacing-induced arrhythmias. Notably, concomitant treatment with apocynin, an inhibitor of NADPH oxidase, prevented these ectopic ventricular events. Together, our results reveal that hearts become arrhythmogenic during dexamethasone treatment, uncovering the pivotal role of ROS-generating NADPH oxidases for arrhythmias vulnerability.

Antiedematogenic and Anti-Inflammatory Activity of the Monoterpene Isopulegol and Its β-Cyclodextrin (β-CD) Inclusion Complex in Animal Inflammation Models

Isopulegol (ISO) is an alcoholic monoterpene widely found in different plant species, such as Melissa officinalis, and has already been reported to have a number of pharmacological properties. Like other terpenes, ISO is a highly volatile compound that is slightly soluble in water, so its inclusion into cyclodextrins (CDs) is an interesting approach to increase its solubility and bioavailability. Thus, our aim was to evaluate the antiedematogenic and anti-inflammatory activity of isopulegol and a β-cyclodextrin-isopulegol inclusion complex (ISO/β-CD) in rodent models. For the anti-inflammatory activity evaluation, antiedematogenic plethysmometry and acute (peritonitis and pleurisy), as well as chronic (cotton pellet-induced granuloma) anti-inflammatory models, were used. The docking procedure is used to evaluate, analyze, and predict their binding mode of interaction with H1 and Cox-2 receptors. The animals (n = 6) were divided into groups: ISO and ISO/β-CD, negative control (saline), and positive control (indomethacin and promethazine). ISO and ISO/β-CD were able to reduce acute inflammatory activity by decreasing albumin extravasation, leukocyte migration, and MPO concentration, and reducing exudate levels of IL-1β and TNF-α. ISO and ISO/β-CD significantly inhibited edematogenic activity in carrageenan- and dextran-induced paw edema. Moreover, both significantly reduced chronic inflammatory processes, given the lower weight and protein concentration of granulomas in the foreign body granulomatous inflammation model. The results suggest that the inclusion of ISO in β-cyclodextrins improves its pharmacological properties, with the histamine and prostaglandin pathways as probable mechanisms of inhibition, and also reinforces the anti-inflammatory profile of this terpene.

Protective effects of flavonoid composition rich P. subpeltata Ortega. on indomethacin induced experimental ulcerative colitis in rat models of inflammatory bowel diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Polyphenolics (flavonoid and phenolic) rich plants are the effective source for the treatment of acute and chronic degenerative diseases including inflammatory bowel disease.

OBJECTIVE

This study was aimed to examine the effects of polyphenolics rich leaf acetone extract of P. subpeltata against the indomethacin induced ulcerative colitis in rats.

MATERIALS AND METHODS

Two consecutive days administration of indomethacin produced chronic inflammation in GIT tissues of rats. Further, the plant extract 200 and 400 mg/kg treatment were continued until 11th day. Then hematological, enzymatic antioxidants, MPO and histological evaluations were analyzed. Moreover, the extracts were treated with RAW267.4 cells for the cytotoxicity, NO and TNF-α analysis.

RESULTS

The obtained results revealed, that higher dose of the plant extract dropped neutrophil infiltration followed by inhibiting the MPO enzyme levels and controls the enzymatic antioxidants such as SOD, CAT, GSH and LPO. RAW cells study also proved that the plant extract effectively inhibits NO and TNF-α production.

CONCLUSIONS

Thus, these results suggest that P. subpeltata extract may have therapeutic potential for the treatment of IBD although further clinical research is still warranted.

Effect of α-Bisabolol and Its β-Cyclodextrin Complex as TetK and NorA Efflux Pump Inhibitors in Staphylococcus aureus Strains

Efflux pumps are proteins present in the plasma membrane of bacteria, which transport antibiotics and other compounds into the extracellular medium, conferring resistance. The discovery of natural efflux pump inhibitors is a promising alternative. α-Bisabolol is a sesquiterpene isolated from several plants such as Matricaria chamomilla L. and has important properties such as antibacterial and anti-inflammatory activity. Currently, the formation of inclusion complexes with β-Cyclodextrin has been used for improving the physicochemical characteristics of the host molecule. This study evaluated the effect of α-Bisabolol, in isolation and in complexation with β-Cyclodextrin, as TetK and NorA efflux pump inhibitors in Staphylococcus aureus strains. The minimum inhibitory concentration (MIC) was determined. Subsequently, inhibitory activity over the pumps was observed by an MIC reduction for the antibiotics, by using subinhibitory concentrations (MIC/8) in combination with tetracycline and norfloxacin. The MIC of the compounds was ≥1024 μg/mL. α-Bisabolol potentiated the action of tetracycline and reduced the MIC of norfloxacin to a clinically relevant concentration. The complexed substance showed synergism however, the effect of the isolated α-Bisabolol was superior to the complex. These results indicate α-Bisabolol is a potential substance to be used as an efflux pump inhibitor.

Effects of the solid lipid nanoparticle of carvacrol on rodents with lung injury from smoke inhalation

The aim of this present study was to evaluate the effect of solid lipid nanoparticles (SLN) containing carvacrol over the lung damage of airway smoke inhalation. The study was conducted with 30 rats subjected to smoke inhalation and divided into 5 groups such as, normal control, negative control, oxygen group, SLN alone, and SLN+CARV group. The animals were sacrificed 24 h after the induction of inhalation injury further, the tissues of larynx, trachea, and lungs were collected for the histological, hematological, myeloperoxidase, and malondialdehyde analysis. The obtained results showed that treatment with CARV+SLN minimized the inhalation injury, since it reduced malondialdehyde significantly, when compared to the negative control group and minimized the histological changes which proves the absence of pulmonary emphysema and exudate in laryngeal and tracheal lumen in the CARV+SLN-treated group. Meanwhile, the presence of lesion with chronic characteristics was observed in the negative control and oxygen groups. It is suggested that the SLN containing carvacrol minimized oxidative stress and histological damages generated from smoke inhalation in rodents.

Design, synthesis and pharmacological evaluation of CVIB, a codrug of carvacrol and ibuprofen as a novel anti-inflammatory agent

The search for new drugs with anti-inflammatory properties remains a challenge for modern medicine. Among the various strategies for drug discovery, deriving new chemical entities from known bioactive natural and/or synthetic compounds remains a promising approach. Here, we designed and synthesized CVIB, a codrug developed by association of carvacrol (a phenolic monoterpene) with ibuprofen (a non-steroidal anti-inflammatory drug). In silico pharmacokinetic and physicochemical properties evaluation indicated low aqueous solubility (LogP ≥5.0). Nevertheless, the hybrid presented excellent oral bioavailability, gastrointestinal tract absorption, and low toxicity. CVIB did not present cytotoxicity in peripheral blood mononuclear cells (PBMCs), and promoted a significant reduction in IL-2, IL-10, IL-17, and IFN-γ cytokine levels in vitro. The LD₅₀ was estimated to be approximately 5000 mg/kg. CVIB was stable and detectable in human plasma after 24 h. In vivo anti-inflammatory evaluations revealed that CVIB at 10 and 50 mg/kg i.p. caused a significant decrease in total leukocyte count (p < 0.01) and provoked a significant reduction in IL-1β (p < 0.01). CVIB at 10 mg/kg i.p. efficiently decreased inflammatory parameters better than the physical mixture (carvacrol + ibuprofen 10 mg/kg i.p.). The results suggest that the codrug approach is a good option for drug design and development, creating the possibility of combining NSAIDs with natural products in order to obtain new hybrid drugs may be useful for treatment of inflammatory diseases.

Anti-hyperalgesic effect of (-)-α-bisabolol and (-)-α-bisabolol/β-Cyclodextrin complex in a chronic inflammatory pain model is associated with reduced reactive gliosis and cytokine modulation

Chronic pain is a continuous or recurring pain which exceeds the normal course of recovery to an injury or disease. According to the origin of the chronic pain, it can be classified as inflammatory or neuropathic. This study aimed to evaluate the antinociceptive and anti-inflammatory effect of (-)-α-bisabolol (BIS) alone and complexed with β-cyclodextrin (βCD) in preclinical models of chronic pain. Chronic pain was induced by Freund's Complete Adjuvant (FCA) or partial lesion of the sciatic nerve (PLSN). Swiss mice were treated with BIS, BIS-βCD (50 mg/kg, p.o) or vehicle (control) and mechanical hyperalgesia, thermal hyperalgesia, muscle strength and motor coordination were evaluated. In addition, levels of TNF-α and IL-10 and expression of the ionized calcium-binding adapter protein (IBA-1) were assessed in the spinal cord of the mice. The complexation efficiency of BIS in βCD was evaluated by High-Performance Liquid Chromatography. BIS and BIS-βCD reduced (p < 0.001) mechanical and thermal hyperalgesia. No alterations were found in force and motor coordination. In addition, BIS and BIS-βCD inhibited (p < 0.05) TNF-α production in the spinal cord and stimulated (p < 0.05) the release of IL-10 in the spinal cord in PLSN-mice. Further, BIS and BIS-βCD reduced IBA-1 immunostaining. Therefore, BIS and BIS-βCD attenuated hyperalgesia, deregulated cytokine release and inhibited IBA-1 expression in the spinal cord in the PLSN model. Moreover, our results show that the complexation of BIS in βCD reduced the therapeutic dose of BIS. We conclude that BIS is a promising molecule for the treatment of chronic pain.

Ximenia americana L. enhances the antibiotic activity and inhibit the development of kinetoplastid parasites

OBJECTIVE

The objective of this work was evaluate the cytotoxic, leishmanicidal and tripanocidal activity, as well as to evaluate its antimicrobial and modulatory activity in association with different antibiotics of the hydroethanolic extract of the Ximenia Americana stem bark (EHXA).

METHOD

In vitro tests against Trypanosoma cruzi, Leishmania sp. and citotoxicity were performed. The evaluation of the antibacterial and bacterial resistance modulatory effect was given by the microdilution method.

RESULTS

The chemical profile show different classes of compounds with significant presence of quercetrin and caffeic acid. The EHXA demonstrated activity only in the concentration of 1000 μg/mL against the L. infantum and L. brasiliensis promastigotes, causing mortality percentage of 40.66 and 27.62%, respectively. The extract presented a significant toxicity only in the concentration of 1000 μg/mL, causing a mortality of 55.42% of fibroblasts. The antibacterial activity of the EHXA demonstrated a MIC value ≥1024 μg/mL against all the tested bacteria. However, in the modulation assay with EHXA in association with different antibiotics the extract had a synergistic effect against S. aureus strains when associated with norfloxacin.

CONCLUSION

The results of this investigation demonstrate for the first time the chemical composition of the hydroethanolic extract of the Ximenia Americana stem bark, your potential antiparasitic and modulatory effect. The low cytotoxic and biological potential against S. aureus open therapeutic perspectives against leishmaniosis and bacterial infections.

Natural products as a perspective for cancer pain management: A systematic review

BACKGROUND

Cancer is the leading cause of death in the world and one of the main symptoms affecting these individuals is chronic pain, which must be evaluated and treated in its various components. Several drugs are currently used, but beyond the high cost, they have harmful side effects to patients or are transitorily effective. Ergo, there is a need to look for new options for cancer pain relief. Natural products (NPs) present themselves as strong candidates for the development of new drugs for the treatment of chronic pain, such as cancer pain.

PURPOSE

This systematic review aimed to summarize current knowledge about the analgesic profile of NPs in cancer pain.

METHODS

The search included PubMed, Scopus and Web of Science (from inception to June 2018) sought to summarize the articles studying new proposals with NPs for the management of oncological pain. Two independent reviewers extracted data on study characteristics, methods and outcomes.

RESULTS

After an extensive survey, 21 articles were selected, which described the analgesic potential of 15 natural compounds to relieve cancer pain. After analyzing the data, it can be suggested that these NPs, which have targets in central and peripheral mechanisms, are interesting candidates for the treatment of cancer pain for addressing different pharmacological mechanisms (even innovative), but ensuring the safety of these compounds is still a challenge. Likewise, the cannabinoids compounds leave the front as the most promising compounds for direct applicability due to the clinical studies that have already been developed and the background already established about these effects on chronic pain.

CONCLUSION

Regarding these findings, it can be concluded that the variability of possible biological sites of action is strategic for new perspectives in the development of therapeutic proposals different from those available in the current market.

The role of interleukins in vitiligo: a systematic review

Vitiligo is a disorder of the skin that causes depigmentation and asymptomatic macules whose exact cause is still unclear. Although its aetiology is not fully elucidated, the main theory of its pathomechanism is that it is associated with the autoimmune process. There is few summarized information about the role of inflammatory mediators, as interleukins, in vitiligo, so our aim was to present a systematic review of the role of interleukins in vitiligo, focusing on interleukins. In this review, we included all studies assessing interleukin levels in vitiligo patients conducted up to June 2017. Quality assessment of these studies was performed using the Newcastle-Ottawa Scale (NOS). The interleukins mainly involved were IL-2, IL-4, IL-6, IL-10 and IL-17. The studies highlight the crucial role of IL-17 in the onset and progression of the disease, and its synergistic action with IL-2, IL-6 and IL-33. Dysregulated levels of the interleukins were also correlated with the stage of disease, the affected skin surface area, and indicated as the main factor for lymphocyte infiltration found in depigmented regions. These findings illustrate the growing need for new therapies targeting vitiligo and further research into the role of interleukins as an area of particular interest.

Myrtenol protects against myocardial ischemia-reperfusion injury through antioxidant and anti-apoptotic dependent mechanisms

Myrtenol is a monoterpene with multiple pharmacological activities. However, although monoterpenes have been proposed to play beneficial roles in a variety of cardiac disorders, pharmacological actions of myrtenol in the heart are not yet reported. Hence, the aim of this study was to evaluate whether myrtenol promotes cardioprotection against myocardial ischemia-reperfusion (IR) injury, and the mechanisms involved in these effects. Male Wistar rats were orally treated for seven consecutive days with myrtenol (50 mg/kg) or N-acetyl cysteine (1.200 mg/kg, NAC). Afterward, hearts were subjected to myocardial IR injury. Here, we show that the severe impairment of contractile performance induced by IR was significantly prevented by myrtenol or NAC. Moreover, myrtenol abolished aberrant electrocardiographic waveform (ST-segment elevation), as well as reduced life-threatening arrhythmias and infarct size induced by IR injury. Importantly, myrtenol fully prevented the massive increase of cardiac reactive oxygen species generation and oxidative stress damage. Accordingly, myrtenol restored the impairment of endogenous antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase and reductase) activities and balance of pro- and anti-apoptotic pathways (Bax and Bcl-2), associated with decreased apoptotic cells. Taken together, our data show that myrtenol promotes cardioprotection against IR injury through attenuation of oxidative stress and inhibition of pro-apoptotic pathway.

Antinociceptive effect of Aristolochia trilobata stem essential oil and 6-methyl-5-hepten-2yl acetate, its main compound, in rodents

Aristolochia trilobata L. is an aromatic plant, popularly known as "mil-homens", and its essential oil (EO) is generally used to treat colic, diarrhea and dysentery disorders. We evaluated the antinociceptive effect of A. trilobata stem EO and of its major compound, the (R)-(-)-6-methyl-5-hepten-2-yl acetate (sulcatyl acetate: SA), using acetic acid (0.85%)-induced writhing response and formalin-induced (20 μL of 1%) nociceptive behavior in mice. We also evaluated the EO and SA effect on motor coordination, using the rota-rod apparatus. EO (25, 50 and 100 mg/kg) or SA (25 and 50 mg/kg) reduced nociceptive behavior in the writhing test (p<0.001). EO (100 mg/kg) and SA (25 and 50 mg/kg) decreased the nociception on the first phase of the formalin test (p<0.05). On the second phase, EO (25: p<0.01; 50: p<0.05 and 100 mg/kg: p<0.001) and SA (25 and 50 mg/kg; p<0.001) reduced the nociceptive response induced by formalin. EO and SA were not able to cause changes in the motor coordination of animals. Together, our results suggest that EO has an analgesic profile and SA seems to be one of the active compounds in this effect.

Protective effect of carvacrol on acetic acid-induced colitis

The pharmacological therapy for inflammatory bowel diseases continues to be problematic, and requires new alternative options. In this study, we tested the hypothesis that carvacrol (CAR), a phenolic monoterpene with anti-inflammatory and antioxidant activities, can treat experimental colitis in mice. C57BL/6 mice (n=8/group) were subjected to intrarectal administration of acetic acid (5%) to induce colitis. Mice were pretreated with CAR (25, 50 or 100mg/kg, p.o.) every 12h for three days prior to the induction. Abdominal hyperalgesia, macroscopic and microscopic colon damage, myeloperoxidase (MPO) activity, tumor necrosis factor (TNF)-α and interleukin (IL)-1β levels, oxidative stress markers, and antioxidant enzyme activities were evaluated. Pretreatment with all doses of CAR significantly decreased abdominal hyperalgesia and colon MPO activity and TNF-α and IL-1β levels. A reduction in macroscopic and microscopic damage (p<0.05) was observed at doses of 50 and 100mg/kg CAR. Pretreatment with CAR significantly reduced lipid peroxidation (for all doses) and increased sulfhydryl groups (at 100mg/kg). This effect was accompanied by a significant increase in catalase, superoxide dismutase, and glutathione peroxidase activities. These findings indicate that CAR protected mice from acetic acid-induced colitis by reducing inflammatory, nociceptive, and oxidative damages.

Hesperetin-loaded lipid-core nanocapsules in polyamide: a new textile formulation for topical drug delivery

Chronic venous insufficiency is characterized by chronic reflux disorder of blood from the peripheral to the central vein, with subsequent venous hypertension and resulting changes in the skin. Traditionally, nonsurgical treatments relied on the use of compression therapy, and more recently a variety of flavonoids have been shown to have positive effects. There have also been developments of more effective drug delivery systems using various textiles and nanotechnology to provide new therapeutic options. Our objective was to use nanotechnology to develop a new formulation containing hesperetin (Hst), a substance not previously used in the treatment of chronic venous insufficiency, impregnated into textile fibers as a possible alternative treatment of venous diseases. We prepared the nanocapsules using the interfacial deposition of preformed polymer method with an Hst concentration of 0.5 mg/mL and then characterized the size and distribution of particles. To quantify the Hst in the samples, we developed an analytical method using high-performance liquid chromatography. Studies of encapsulation efficiency (98.81%±0.28%), microscopy, drug release (free-Hst: 104.96%±12.83%; lipid-core nanocapsule-Hst: 69.90%±1.33%), penetration/permeation, drug content (0.46±0.01 mg/mL) and the effect of washing the textile after drug impregnation were performed as part of the study. The results showed that nanoparticles of a suitable size and distribution with controlled release of the drug and penetration/permeation into the skin layers were achieved. Furthermore, it was established that polyamide was able to hold more of the drug, with a 2.54 times higher content than the cotton fiber; after one wash and after five washes, this relation was 2.80 times higher. In conclusion, this is a promising therapeutic alternative to be further studied in clinical trials.

Molecular Modeling and Physicochemical Properties of Supramolecular Complexes of Limonene with α- and β-Cyclodextrins

This study evaluated three different methods for the formation of an inclusion complex between alpha- and beta-cyclodextrin (α- and β-CD) and limonene (LIM) with the goal of improving the physicochemical properties of limonene. The study samples were prepared through physical mixing (PM), paste complexation (PC), and slurry complexation (SC) methods in the molar ratio of 1:1 (cyclodextrin:limonene). The complexes prepared were evaluated with thermogravimetry/derivate thermogravimetry, infrared spectroscopy, X-ray diffraction, complexation efficiency through gas chromatography/mass spectrometry analyses, molecular modeling, and nuclear magnetic resonance. The results showed that the physical mixing procedure did not produce complexation, but the paste and slurry methods produced inclusion complexes, which demonstrated interactions outside of the cavity of the CDs. However, the paste obtained with β-cyclodextrin did not demonstrate complexation in the gas chromatographic technique because, after extraction, most of the limonene was either surface-adsorbed by β-cyclodextrin or volatilized during the procedure. We conclude that paste complexation and slurry complexation are effective and economic methods to improve the physicochemical character of limonene and could have important applications in pharmacological activities in terms of an increase in solubility.

Geraniol Induces Antinociceptive Effect in Mice Evaluated in Behavioural and Electrophysiological Models

Geraniol (GER) is a monoterpene alcohol with various biochemical and pharmacological properties present in the essential oil of more than 160 species of herbs (especially the Cymbopogon genus). In this study, we evaluated the antinociceptive activity of GER in behavioural and electrophysiological in vitro experimental models of nociception using male Swiss mice. GER (12.5, 25 or 50 mg/kg i.p. and 50 or 200 mg/kg p.o.) reduced the number of writhes induced by acetic acid. The opioid antagonist naloxone (5 mg/kg s.c.) administered in mice subsequently treated with GER (25 mg/kg i.p.) did not reverse such antinociceptive activity, suggesting a non-opioid pathway for the mechanism of action. GER (12.5, 25 and 50 mg/kg i.p.) reduced paw licking time in the second phase of the formalin test. Also, in the glutamate test, GER when administered 50 mg/kg i.p. reduced paw licking time, probably modulating glutamatergic neurotransmission. GER blocked reversibly components of the compound action potential (CAP) recorded in isolated sciatic nerve in a concentration- and drug exposure time-dependent manner: 1 mM to 120 min. for the first component and 0.6 mM to 90 min. for the second component. The IC₅₀ was calculated for the peak-to-peak amplitude (PPA) at 0.48 ± 0.04 mM. The conduction velocity was also reduced by exposure to GER starting from the concentration of 0.3 mM for both components of the CAP. In conclusion, it is suggested that GER has antinociceptive activity, especially in pain related to inflammation, and in part related to reduced peripheral nerve excitability.

Palladium-benzodiazepine derivatives as promising metallodrugs for the development of antiepileptic therapies

We synthesized two organometallic diazepam-palladium(II) derivatives by C-H activation of diazepam (DZP) with palladium salts, i.e., PdCl2 and Pd(OAc)2 (OAc=acetate). Both compounds obtained are air stable and were isolated in good yields. The anticonvulsant potential of the complexes, labeled [(DZP)PdCl]2 and [(DZP)PdOAc]2, was evaluated through two animal models: pentylenetetrazole (PTZ)- and picrotoxin (PTX)-induced convulsions. The organometallic DZP-palladium(II) acetate complex, [(DZP)PdOAc]2, significantly increased (p<0.01 or p<0.001) latencies and protected the animals against convulsions induced by PTZ and PTX, while the analogous chloro derivative, [(DZP)PdCl]2, was effective (p<0.01) only in the PTZ model. These effects appear to be mediated through the GABAergic system. The possible mechanism of action of the DZP-palladium(II) complexes was also confirmed with the use of flumazenil (FLU), a GABAA-benzodiazepine receptor complex site antagonist. Herein, we present the first report of the anticonvulsant properties of organometallic DZP-palladium(II) complexes as well as evidence that these compounds may play an important role in the study of new drugs to treat patients with epilepsy.

Hydroalcoholic extract of red propolis promotes functional recovery and axon repair after sciatic nerve injury in rats

CONTEXT

Peripheral axon injury and degeneration are often mediated by oxidative stress and inflammation. The hydroalcoholic extract of the red propolis (HERP) has attracted great attention because of its antioxidant and anti-inflammatory activities.

OBJECTIVE

The objective of this work is to study the effect of HERP on nerve repair and functional recovery after sciatic nerve injury (SNI) in rats.

MATERIALS AND METHODS

The chemical markers in HERP were identified using high-resolution mass spectroscopy. After axonotmesis of sciatic nerve, ibuprofen (IBP) and HERP treatments were orally administered for 28 d. Behavioural tests were performed weekly after SNI. The myelinated axon number was counted using morphometric analysis.

RESULTS

The compounds found in HERP were pinocembrin, formononetin, vestitol, and biochanin A. The animals that underwent SNI showed a significant decrease in motor function based on the Basso, Beattie and Bresnahan scale and sciatic functional index compared with sham animals until 7 d after the surgery (p < 0.05). After 14 and 21 d, the SNI groups treated with either HERP or IBP showed significant improvement (p < 0.01), and the SNI group treated with HERP 10 mg/kg showed accelerated motor recovery compared with the other groups (p < 0.01). SNI caused also a reduction in the myelinated axon counts, and treatment with HERP 10 mg/kg induced a significant increase in the number of myelinated fibres compared with all other groups.

CONCLUSION

HERP promoted regenerative responses and accelerated functional recovery after sciatic nerve crush. Thus, it can be considered to be a new strategy or complementary therapy for treating nerve injuries.

Structure–activity relationship of terpenes with anti-inflammatory profile – a systematic review

Inflammation is a complex biological response that in spite of having available treatments, their side effects limit their usefulness. Because of this, natural products have been the subject of incessant studies, among which the class of terpenes stands out. They have been the source of study for the development of anti-inflammatory drugs, once their chemical diversity is well suited to provide skeleton for future anti-inflammatory drugs. This systematic review reports the studies present in the literature that evaluate the anti-inflammatory activity of terpenes suffering any change in their structures, assessing whether these changes also brought changes in their effects. The search terms anti-inflammatory agents, terpenes, and structure–activity relationship were used to retrieve English language articles in SCOPUS, PUBMED and EMBASE published between January 2002 and August 2013. Twenty-seven papers were found concerning the structural modification of terpenes with the evaluation of antiinflammatory activity. The data reviewed here suggest that modified terpenes are an interesting tool for the development of new anti-inflammatory drugs.

The anti-hyperalgesic and anti-inflammatory profiles of p-cymene: Evidence for the involvement of opioid system and cytokines

CONTEXT

Pain corresponds to the most frequent reason for visits to physicians, and its control by conventional drugs is accompanied by several side effects, making treatment difficult. For this reason, new chemical entities derived from natural products still hold great promise for the future of drug discovery to pain treatment.

OBJECTIVE

The objective of this study was to evaluate the antinociceptive and anti-inflammatory profiles of p-cymene (PC), a monocyclic monoterpene, and its possible mechanisms of action.

MATERIALS AND METHODS

Mice treated acutely with PC (25, 50, or 100 mg/kg, i.p.) were screened for carrageenan-induced hyperalgesia and the inflammatory components of its cascade (30-180 min), carrageenan-induced pleurisy (4 h), and tail-flick test (1-8 h). Also, we observed the PC effect on the generation of nitric oxide by macrophages and the activation of neurons in the periaqueductal gray (PAG) by immunofluorescence.

RESULTS

PC reduced (p < 0.001) the hyperalgesia induced by carrageenan, TNF-α, dopamine, and PGE2. PC decrease total leukocyte migration (100 mg/kg: p < 0.01), neutrophils (50 and 100 mg/kg: p < 0.05 and 0.001), and TNF-α (25, 50, and 100 mg/kg: p < 0.01, 0.05, and 0.001, respectively), besides reducing NO production (p < 0.05) in vitro. PC produced antinociceptive effect in tail-flick test (p < 0.05), which was antagonized by naloxone, naltrindole, nor-BNI, and CTOP, and increased (p < 0.001) the number of c-Fos-immunoreactive neurons in PAG.

DISCUSSION AND CONCLUSION

These results provide information about the anti-hyperalgesic and anti-inflammatory properties of PC suggesting a possible involvement of the opioid system and modulating some pro-inflammatory cytokines.

Citronellal, a monoterpene present in Java citronella oil, attenuates mechanical nociception response in mice

CONTEXT

Citronellal is a monoterpene present in the oil of many species, including Cymbopogon winterianus Jowitt (Poaceae).

OBJECTIVE

The present study investigated the effect of citronellal on inflammatory nociception induced by different stimuli and examined the involvement of the NO-cGMP-ATP-sensitive K⁺ channel pathway.

MATERIALS AND METHODS

We used male Swiss mice (n = 6 per group) that were treated intraperitoneally with citronellal (25, 50 or 100 mg/kg) 0.5 h after the subplantar injection of 20 μl of carrageenan (CG; 300 µg/paw), tumor necrosis factor-α (TNF-α; 100 pg/paw), prostaglandin E₂ (PGE₂; 100 ng/paw) or dopamine (DA; 30 μg/paw). The mechanical nociception was evaluated at 0.5, 1, 2 and 3 h after the injection of the agents, using a digital analgesimeter (von Frey). The effects of citronellal were also evaluated in the presence of L-NAME (30 mg/kg) or glibenclamide (5 mg/kg).

RESULTS

At all times, citronellal in all doses inhibited the development of mechanical nociception induced by CG (p < 0.001 and p < 0.01) and TNF-α (p < 0.001, p < 0.01, and p < 0.05). The citronellal was able to increase the pain threshold in the DA test (p < 0.001, p < 0.01, and p < 0.05) and in the PGE₂ test at all times (p < 0.001 and p < 0.05). L-NAME and glibenclamide reversed the antinociceptive effects of the citronellal at higher doses in the PGE₂ test.

DISCUSSION AND CONCLUSION

These data suggest that citronellal attenuated mechanical nociception, mediated in part by the NO-cGMP-ATP-sensitive K⁺ channel pathway.

Improvement of p-cymene antinociceptive and anti-inflammatory effects by inclusion in β-cyclodextrin

Previously, we have demonstrated the analgesic-like property of p-cymene in rodents. Short half-life is a limitation for p-cymene application and several approaches have been used to improve pharmaceutical properties of monoterpenes, including the employment of drug-delivery systems. Here, we used p-cymene/β-cyclodextrin (β-CD) complex and p-cymene (PC) isolated to evaluated whether the complex formulation is able to improve the antinociceptive activity of this monoterpene. Male mice (26-30g) were pretreated with PC/β-CD (20 or 40mg/kg, p.o.), PC (20 or 40mg/kg, p.o.) or vehicle (distilled water), 0.5h before painful tests and antinociceptive effect was evaluated at times: 0.5, 1, 2, 4, 8, and 16h after treatment. We evaluated the analgesic-like effect of PC/β-CD and PC in acetic acid-induced abdominal writhes, hot-plate, carrageenan-induced paw edema and in rota-rod apparatus. Our results demonstrated that acute treatment with complex PC/β-CD produced an antinocicepitve effect (p<0.01 or p<0.001) for 8h followed whereas isolated PC produced the same effect for 2h. Similar results were obtained in hot-plate test, PC/β-CD, in all doses, significantly reduces (p<0.01 or p<0.001) nociceptive behavior for 8h while isolated PC for 1h, did so only in higher dose. Such results were unlikely to be caused by motor abnormality. Systemic pretreatment with PC/β-CD and PC inhibited the development paw edema by carrageenan 1%, but PC/β-CD did so during a longer period when compared with isolated monoterpene alone. Our results provide evidence to propose that the complex with β-CD improved analgesic and anti-inflammatory effects of p-cymene.

Antinociceptive effect of ethanolic extract of Selaginella convoluta in mice

BACKGROUND

Selaginella convoluta (Arn.) Spring (Selaginellaceae), commonly known as "jericó", is a medicinal plant found in northeastern Brazil. S. convoluta is used in folk medicine as an antidepressant, aphrodisiac, diuretic, analgesic, anti-inflammatory and it is used to combat amenorrhea, coughing and bleeding. This study was performed to evaluate the antinociceptive effects of ethanolic extract from S. convoluta in mice exposed to chemical and thermal models of nociception.

METHODS

Preliminary phytochemical analysis of the ethanolic extract was performed. The ethanolic extract from Selaginella convoluta (Sc-EtOH) was examined for its intraperitoneal (i.p.) antinociceptive activity at the doses of 100, 200 and 400 mg/kg body weight. Acetic acid-induced writhing, formalin injection and hot plate tests were used to evaluate the antinociceptive activity of Sc-EtOH extract. The rota-rod test was used to evaluate motor coordination.

RESULTS

A preliminary analysis of Sc-EtOH revealed that it contained phenols, steroids, terpenoids and flavonoids. In the acetic acid-induced writhing test, mice treated with Sc-EtOH (100, 200 and 400 mg/kg, i.p.) exhibited reduced writhing (58.46, 75.63 and 82.23%, respectively). Secondly, Sc-EtOH treatment (100, 200 and 400 mg/kg, i.p.) decreased the paw licking time in mice during the first phase of the formalin test (by 44.90, 33.33 and 34.16%, respectively), as well as during the second phase of the test (by 86.44, 56.20 and 94.95%, respectively). Additionally, Sc-EtOH treatment at doses of 200 and 400 mg/kg increased the latency time in the hot plate test after 60 and 90 minutes, respectively. In addition, Sc-EtOH did not impair motor coordination.

CONCLUSION

Overall, these results indicate that Sc-EtOH is effective as an analgesic agent in various pain models. The activity of Sc-EtOH is most likely mediated via the inhibition of peripheral mediators and central inhibitory mechanisms. This study supports previous claims of traditional uses for S. convoluta.

Evaluation of adherence to treatment by patients seen in a psychosocial care center in northeastern Brazil

In the treatment of mental disorders, nonadherence to medication, the main cause of psychiatric morbidity, is observed in about 50% of the cases and is responsible for numerous losses. This study evaluated adherence to drug treatment by patients seen in a Psychosocial Care Center (CAPS) in northeastern Brazil. Adherence to treatment was evaluated using the Haynes-Sackett and Morisky-Green-Levine tests. All patients registered in the CAPS were included in the study (n= 101). Only 11.88% of the patients adhered to drug treatment. The main reasons not to use medication were: oblivion (68.83%), feeling unwell after taking the medication (54.22%), not having money to buy the medication (43.83%), not finding the medication in the public health service (39.94%) and fear of harm that might be caused by the drug (28.90%). Furthermore, 85.1% of the patients did not know their diseases, 88.1% did not know their treatment, 86.4% did not feel good when they took their medication, and 88.1% took their medication incorrectly. The results revealed that the lack of information about diseases and drugs used, the nuisance posed by drug therapy and the low access to medications reduce adherence to treatment and, consequently, treatment effectiveness.

Anti-inflammatory and toxicity studies of atranorin extracted from Cladina kalbii Ahti in rodents

Atranorin (ATR) is the main compound from the lichen Cladina kalbii Ahti, which grows in the arid regions of northeastern Brazil. This study was conducted to evaluate the anti-inflammatory and toxicological properties of ATR. To evaluate anti-inflammatory properties, paw edema was induced by injecting 0.1 mL of carrageenan into the subplantar region of the right hind paw of rats, and leukocyte migration was induced by injection of 500 µL of carrageenan into the peritoneal cavity of mice. In addition, we determined ATR cytotoxicity in L929 cells by MTT assay and acute (5 g/kg-single dose) and subchronic (50 mg/kg-30 days) toxicity tests in Wistar rats. The results showed that ATR (100 mg/kg and 200 mg/kg) exhibited significant anti-inflammatory activity (paw edema and leukocyte migration). In the acute toxicity test, the animals showed hypoactivity and lethargy during the initial period (first 6 hours) and increase in total protein, total and indirect bilirubin, and alkaline phosphatase after 14 days in ATR-treated male rats. The subchronic toxicity test revealed increases in total protein, globulin, gamma-glutamyl transferase, alkaline phosphatase, and total and direct bilirubin in ATR-treated female rats. Histological analysis revealed no changes in the architecture and morphology of the organs. These results suggest that ATR has significant anti-inflammatory activity, with no significant acute and subchronic toxicity or cytotoxicity.

Morinda citrifolia Linn leaf extract possesses antioxidant activities and reduces nociceptive behavior and leukocyte migration

Herbal drugs have been used since ancient times to treat a wide range of diseases. Morinda citrifolia Linn (popularly known as "Noni") has been used in folk medicine by Polynesians for over 2,000 years. It is reported to have a broad range of therapeutic effects, including effects against headache, fever, arthritis, gingivitis, respiratory disorders, infections, tuberculosis, and diabetes. The aim of this study was to investigate the antioxidant, anti-inflammatory, antinociceptive, and antibacterial properties of the aqueous extract from M. citrifolia leaves (AEMC). Antioxidant activity was observed against lipid peroxidation, nitric oxide, and hydroxyl radicals. The antinociceptive effect of AEMC was observed in the acetic acid-induced writhing test at the higher dose. Moreover, AEMC significantly reduced the leukocyte migration in doses of 200 and 400 mg/kg and showed mild antibacterial activity. Together, the results suggest that properties of M. citrifolia leaf extract should be explored further in order to achieve newer tools for managing painful and inflammation conditions, including those related to oxidant states.

Cardiovascular effects induced by Cymbopogon winterianus essential oil in rats: involvement of calcium channels and vagal pathway

OBJECTIVES

This study has investigated the cardiovascular effects of the Cymbopogon winterianus essential oil (EOCW) in rats. C. winterianus is a plant used in folk medicine for the treatment of hypertension.

METHODS

For the measurement of haemodynamic and ECG parameters, male Wistar rats under anaesthesia were cannulated in the abdominal aorta and lower vena cava and electrodes were subcutaneously implanted in their paws. For an in-vitro approach, the rats were killed and the superior mesenteric artery was removed and cut into rings (1-2 mm). These rings were then mounted in organ baths containing Tyrode's solution at 37 degrees C and gassed with carbogen.

KEY FINDINGS

In rats, EOCW (1-20 mg/kg, i.v.) induced dose-dependent hypotension and tachycardia. These effects were not affected by L-NAME or indometacin, but were partially reduced after atropine administration. EOCW (20 mg/kg only) also induced bradycardia-associated sinoatrial blockade, junctional rhythm, and first-degree atrioventricular block, which was abolished after atropine administration or vagotomy. In arterial rings, EOCW (0.1-3000 microg/ml) induced relaxation of phenylephrine tonus that was not affected by removal of the endothelium. These relaxations were similar to those observed in rings without endothelium precontracted with KCl 80 mm. EOCW was able to antagonize the CaCl(2) (30-300 mum) induced contractions in depolarizing solution (KCl 60 mm).

CONCLUSIONS

These results demonstrated that EOCW induced hypotension and vasorelaxation. These effects appeared to be mainly mediated by Ca(+2)-channel blocking. Furthermore, the higher dose of EOCW induced transient bradycardia and arrhythmias due to a cardiac muscarinic activation secondary to a vagal discharge.

Antinociceptive effect of citronellal in mice

Citronellal is a monoterpene reported to be a major component of the essential oils in various aromatic species of plants. The present study evaluated the central nervous system depressant and antinociceptive properties of citronellal through behavioral experimental models. Following intraperitoneal injection, citronellal induced the reduction of spontaneous activity, ataxia, analgesia, and sedation. In pentobarbital-induced hypnosis, CTL (citronellal) at 50, 100, and 200 mg/kg (i.p.) significantly increased sleeping time (88.0 +/- 11.4, 100.2 +/- 16.4, and 119.5 +/- 20.9 min) when compared to vehicle solution injections (43.0 +/- 6.1). Citronellal (100 and 200 mg/kg, i.p.) significantly reduced the number of writhes (66.4 and 81.9%) in a writhing test and the number of paw licks during phase 1 (47.0 and 66.8%) and phase 2 (71.1 and 79.2%) of a formalin test when compared to control group animals. In addition, the results of a hot plate test showed central analgesic properties for citronellal (p < 0.05). These results indicate depressant, hypnotic, and antinociceptive properties of this monoterpene.

Antinociceptive effects of citronellal in formalin-, capsaicin-, and glutamate-induced orofacial nociception in rodents and its action on nerve excitability

AIMS

To evaluate the antinociceptive effects of citronellal (CTL) on formalin-, capsaicin-, and glutamate-induced orofacial nociception in mice and to investigate whether such effects might involve a change in neural excitability.

METHODS

Male mice were pretreated with CTL (50, 100, and 200 mg/kg, ip), morphine (5 mg/kg, ip), or vehicle (distilled water plus one drop of Tween 80 0.2%) before formalin (20 microL, 2%), capsaicin (20 microL, 2.5 microg) or glutamate (40 microL, 25 microM) injection into the right vibrissa. Sciatic nerve recordings were made using the single sucrose gap technique in rats. The data obtained were analyzed by ANOVA followed by Dunnett's test for the behavioral analyses and by the Student t test for CAP evaluation.

RESULTS

Pretreatment with CTL was effective in reducing nociceptive face-rubbing behavior in both phases of the formalin test, which was also naloxone-sensitive. CTL produced significantly antinociceptive effect at all doses in the capsaicin- and glutamate- tests. Rota-rod testing indicated that such results were unlikely to be provoked by motor abnormality. Recordings using the single sucrose gap technique revealed that CTL (10 mM) could reduce the excitability of the isolated sciatic nerve through a diminution of the compound action potential amplitude by about 42.4% from control recordings.

CONCLUSION

These results suggest that CTL might represent an important tool for management and/or treatment of orofacial pain.

Phythochemical screening and anticonvulsant activity of Cymbopogon winterianus Jowitt (Poaceae) leaf essential oil in rodents

Cymbopogon winterianus (Poaceae) is used for its analgesic, anxiolytic and anticonvulsant properties in Brazilian folk medicine. This report aimed to perform phythochemical screening and to investigate the possible anticonvulsant effects of the essential oil (EO) from fresh leaves of C. winterianus in different models of epilepsy. The phytochemical analysis of EO showed presence of geraniol (40.06%), citronellal (27.44%) and citronellol (10.45%) as the main compounds. A behavioral screening demonstrated that EO (100, 200 and 400mg/kg; ip) caused depressant activity on CNS. When administered concurrently, EO (200 and 400mg/kg, ip) significantly reduced the number of animals that exhibited PTZ- and PIC-induced seizures in 50% of the experimental animals (p<0.05). Additionally, EO (100, 200 and 400mg/kg, ip) significantly increased (p<0.05) the latencies of clonic seizures induced by STR. Our results demonstrated a possible activity anticonvulsant of the EO.

Antiparkinsonian-like effects of Plumbago scandens on tremorine-induced tremors methodology

Tremorine-induced tremors model is used to evaluate antiparkinsonian drugs because rest tremor is a sign that distinguishes Parkinson's disease (PD) from other diseases. The effects of crude ethanolic extract (CEE) and total acetate fraction (TAF) of Plumbago scandens were investigated at several doses. These extracts at doses of 125 and 250 mg/kg i.p. failed to reduce tremors in tremorine-treated mice. TAF showed significant effects only at a dose of 500 mg/kg. Both CEE and TAF at doses of 1000 and 2000 mg/kg i.p. suppressed the tremors in a dose-dependent fashion for 60 min. Biperiden, an anticholinergic drug, was used as standard at a dose of 3 mg/kg i.p. This study suggests that P. scandens is a plant with possible therapeutic value for PD.

CNS pharmacological effects of the hydroalcoholic extract of Sida cordifolia L. leaves

Sida cordifolia L. (Malvaceae), known as "malva branca", is a plant used in the popular medicine for the treatment stomatits, of asthma and nasal congestion. This work researched the acute toxicity of Sida cordifolia and its action on the central nervous system (CNS) because no data in the literature have been found about of pharmacological activity of this plant in the CNS. The hydroalcoholic extract of Sida cordifolia leaves (HESc) was used and the psychopharmacology approach began with the determination of LD(50), where a low toxicity was observed in mice. Depressive activity on CNS was demonstrated by several alterations in mice's behavior in the pharmacological screening. In the motility test, the HESc showed significant reduction of spontaneous activity at a dose of 1000 mg/kg (i.p.) at 30 and 60 min. The same form the HESc also decreased the ambulation and rearing in open-field test at 30, 60 and 120 min at a dose of 1000 mg/kg (i.p.).