The GABAergic System and Endocannabinoids in Epilepsy and Seizures: What Can We Expect from Plant Oils?

Seizures and epilepsy are some of the most common serious neurological disorders, with approximately 80% of patients living in developing/underdeveloped countries. However, about one in three patients do not respond to currently available pharmacological treatments, indicating the need for research into new anticonvulsant drugs (ACDs). The GABAergic system is the main inhibitory system of the brain and has a central role in seizures and the screening of new ACD candidates. It has been demonstrated that the action of agents on endocannabinoid receptors modulates the balance between excitatory and inhibitory neurotransmitters; however, studies on the anticonvulsant properties of endocannabinoids from plant oils are relatively scarce. The Amazon region is an important source of plant oils that can be used for the synthesis of new fatty acid amides, which are compounds analogous to endocannabinoids. The synthesis of such compounds represents an important approach for the development of new anticonvulsant therapies.

In Vitro Cytotoxic Effects and Mechanisms of Action of Eleutherine Isolated from Eleutherine plicata Bulb in Rat Glioma C6 Cells.

Gliomas are the most common primary malignant brain tumors in adults, and have a poor prognosis, despite the different types of treatment available. There is growing demand for new therapies to treat this life-threatening tumor. Quinone derivatives from plants have received increased interest as potential anti-glioma drugs, due to their diverse pharmacologic activities, such as inhibiting cell growth, inflammation, tumor invasion, and promoting tumor regression. Previous studies have demonstrated the anti-glioma activity of Eleutherine plicata, which is related to three main naphthoquinone compounds-eleutherine, isoeleutherine, and eleutherol-but their mechanism of action remains elusive. Thus, the aim of this study was to investigate the mechanism of action of eleutherine on rat C6 glioma. In vitro cytotoxicity was evaluated by MTT assay; morphological changes were evaluated by phase-contrast microscopy. Apoptosis was determined by annexin V-FITC-propidium iodide staining, and antiproliferative effects were assessed by wound migration and colony formation assays. Protein kinase B (AKT/pAKT) expression was measured by western blot, and telomerase reverse transcriptase mRNA was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Eleutherine reduced C6 cell proliferation in a dose-dependent manner, suppressed migration and invasion, induced apoptosis, and reduced AKT phosphorylation and telomerase expression. In summary, our results suggest that eleutherine has potential clinical use in treating glioma.

Actions of Cannabis sativa L. fixed oil and nano-emulsion on venom-induced inflammation of Bothrops moojeni snake in rats.

BACKGROUND: Bothrops moojeni snake venom (VBm) has toxins that cause pronounced tissue damage and exacerbated inflammatory reaction. Cannabis sativa L. is a plant species that produces an oil (CSO) rich in unsaturated fatty acids. Nano-emulsions have several advantages, such as better stability and higher penetrating power in membranes. Therefore, this study evaluated the effect of a nano-emulsion based on this herbal derivative (NCS) against VBm-induced inflammation in Wistar rats. METHODS: The CSO and NCS were submitted to physicochemical characterization. The inflammatory process was induced by the VBm (0.10 mg/kg) as follows: rat paw edema, peritonitis, analysis of leukocyte infiltrate in gastrocnemius muscle of rats and formation of granulomatous tissue. RESULTS: No significant changes were observed when the NCS was submitted to the centrifugation and thermal stress tests. There was no phase separation, changes in density (0.978 ± 0.01 g/cm3) and viscosity (0.889 ± 0.15). The droplet diameter ranged from 119.7 ± 065 to 129.3 ± 0.15 nm and the polydispersity index ranged from 0.22 ± 0.008 to 0.23 ± 0.011. The results showed that treatments with CSO (200 and 400 mg/kg) and NCS (100 mg/kg) were able to decrease significantly (p < 0.001) the formation of edema and granulomatous tissue. The CSO and NCS groups significantly attenuated (p < 0.001) the recruitment of inflammatory cells in the tests for peritonitis and leukocyte infiltrate. The histopathological analysis of the gastrocnemius muscle showed a reduction in tissue damage caused by VBm. CONCLUSION: The results obtained in this study showed anti-inflammatory activity of the CSO which may be due to a high UFA content. The nanosizing, as evidenced by the incorporation of the CSO in the NCS improved the effect and opens the perspective for the obtainment of a nanomedicine in which a kinetic stable phytotherapic can be used at low doses.

Fatty ethanolamide of Bertholletia excelsa triglycerides (Brazil nuts): anti-inflammatory action and acute toxicity evaluation in Zebrafish (Danio rerio).

Fatty amides (N-alkylamides) are bioactive lipids that are widely distributed in microorganisms, animals, and plants. The low yield in the extraction process of spilantol, a fatty amide, which is mainly related to its diverse biological effects, compromises its application on a large scale. Thus, this study proposes an alternative method to synthesise fatty amides from Bertholletia excelsa (AGBe) oil, with a chemical structure similar to that of spilantol. Carrageenan-induced abdominal oedema in vivo models were used in zebrafish (Danio rerio). In in vivo studies, oral AGBe produced no signs of toxicity. In the histopathological study, AGBe did not cause significant changes in the main metabolising organs (liver, kidneys, and intestines). All doses of AGBe (100 mg/kg, 500 mg/kg, and 750 mg/kg) were effective in reducing oedema by 65%, 69%, and 95%, respectively, producing a dose-response effect compared to the control group, and spilantol-inhibited oedema by 48%. In the in silico study, with the use of molecular docking, it was observed that among the AGBe, the molecules 18:1, ω-7-ethanolamine, and 18:1, ω-9-ethanolamine stood out, with 21 interactions for COX-2 and 20 interactions for PLA2, respectively, surpassing the spilantol standard with 15 interactions for COX-2 and PLA2. The anti-inflammatory action hypothesis was confirmed in the in silico study, demonstrating the involvement of AGBe in the process of inhibiting the enzymes COX-2 and PLA2. Therefore, based on all the results obtained and the fact that until the dose of 1000 mg/kg was administered orally in zebrafish, it was not possible to determine the LD50; it can be said that AGBe is effective and safe for anti-inflammatory activity.

Nanoemulsions with oleoresin of Copaifera reticulata (Leguminosae) improve anthelmintic efficacy in the control of monogenean parasites when compared to oleoresin without nanoformulation.

This study compared the in vitro anthelmintic activity of Copaifera reticulata oleoresin (200, 400, 600, 800 and 1,000 mg/L) and of nanoemulsions prepared with this oleoresin (50, 100, 150, 200 and 250 mg/L) against monogeneans on the gills of Colossoma macropomum. The major compounds present in the oleoresin of C. reticulata were γ-macrocarpene (14.2%), α-bergamotene (13.6%), ß-selinene (13.4%) and ß-caryophyllene (11.7%). All concentrations of the nanoemulsion and the oleoresin without nanoformulation showed anthelmintic efficacy against monogeneans, and higher concentrations led to more rapid parasite mortality. Structural damages to the tegument of the parasites exposed to C. reticulata oleoresin were observed with scanning electron microscopy. At two hours of exposure, fish showed 100% tolerance to all nanoemulsion concentrations used in the in vitro assays, whereas 100% mortality was shown in the fish exposed to the oleoresin without nanoformulation after one hour. The results of this study suggest that nanoemulsions with oleoresin of C. reticulata have advantages in the control and treatment of monogenean infections in C. macropomum when compared to the oleoresin without nanoformulation. In addition, since nanoemulsions with the C. reticulata oleoresin are safe to control monogeneans, the efficacy of these nanoformulations may be assayed in therapeutic baths to treat C. macropomum infected by monogeneans.

Anti-inflammatory and antialgic actions of a nanoemulsion of Rosmarinus officinalis L. essential oil and a molecular docking study of its major chemical constituents.

We evaluate the anti-inflammatory and antialgic potency of a nanoemulsion (NEORO) containing the essential oil of Rosmarinus officinalis L. (EORO), which is composed primarily of limonene, camphor and 1,8-cineole. The EORO and NEORO were administered orally 30 min prior to starting the experiments. In a test of rat paw oedema induced by carrageenan, NEORO was effective in doses of 498 µg/kg, and it inhibited 46% of the maximum peak of the oedema; in a dose of 300 mg/kg, EORO inhibited 50% of the maximum peak of the oedema. In an acetic acid-induced writhing test, NEORO yielded a dose-dependent effect, and a dose of 830 µg/kg inhibited 84% of the algesic process; a dose of 100 mg/kg of EORO inhibited 55%. In an assay for H2S production in rat stomachs, a dose of 498 µg/kg of NEORO inhibited H2S production in all of the measurement phases, and a dose of 100 mg/kg EORO inhibited 60% and influenced the effect of the ethanol significantly, reducing the production of H2S. We suggest that NEORO potentiated the effect of EORO, demonstrating effectiveness in doses 600 times lower than those applied with EORO. Among the major compounds of EORO, the camphor molecule exhibited the largest number of interactions with the therapeutic targets related to the inflammatory process, suggesting that it is responsible for EORO's anti-inflammatory and antialgic effects. This work paves the way for future investigations related to the therapeutic role of NEORO in the inflammation process.

Anti-inflammatory activity of nanoemulsions of essential oil from Rosmarinus officinalis L.: in vitro and in zebrafish studies.

The essential oil from Rosmarinus officinalis L. (OERO) has bioactive compounds with anti-inflammatory activity. The objective of this study was to evaluate the anti-inflammatory potency of nanoemulsions containing essential oil of Rosmarinus officinalis L. (NOERO, NECHA, NECULT, and NECOM) in vitro and in vivo. This study was accomplished in a quantitative format through tests with diphenyl picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), cellular antioxidant activity (CCA), determination of nitric oxide production, cellular viability and anti-inflammatory activity in zebrafish. OERO's were submitted to the analysis-coupled gas chromatography-mass spectrometry (GC-MS), which highlighted 1,8-cineol and camphor as major compounds. NOEROs were obtained by a low-energy method and presenting the medium size smaller than 200 nm. The efficiency of encapsulation by spectrometry and gas chromatographic analysis was 67.61 and 75.38%, respectively. In the CCA assay, all of the samples presented percentage values of inhibition similar to the quercetin pattern, indicating antioxidant activity. In the test for determination of NO·, all of the samples inhibited the production of NO· when compared to LPS, and NOEROS were more effective than OEROS to 5 µg/mL. In the cell viability assay, the cells remained viable after contact with the samples, demonstrating an absence of cytotoxicity. This study showed that all nanoemulsions (NECHA, NECULT, and NECOM) showed no toxicity to macrophages, besides demonstrating antioxidant activity and potentiation of the essential oil effect in the proliferation of viable fibroblasts. Nanoemulsions has also shown the ability to potentiate the anti-inflammatory action of essential oils by exerting immunomodulatory activity by inhibiting the production of the pro-inflammatory mediator nitric oxide. The results obtained with NECHA in zebrafish confirm the hypothesis that prominent terpenic compounds, alpha-pinene, 1,8-cineole, and camphor, became more available at the target sites, inhibiting the inflammatory process in this animal species.

Efficacy of Carapa guianensis oil (Meliaceae) against monogeneans infestations: a potential antiparasitic for Colossoma macropomum and its effects in hematology and histopathology of gills.

This study evaluated the efficacy of therapeutic baths with Carapa guianensis (andiroba) oil against monogeneans of Colossoma macropomum (tambaqui), as well as the hematological and histological effects on fish. Among the fatty acids identified in C. guianensis oil, oleic acid (53.4%) and palmitic acid (28.7%) were the major compounds, and four limonoids were also identified. Therapeutic baths of 1 hour were performed for five consecutive days, and there was no fish mortality in any of the treatments. Therapeutic baths using 500 mg/L of C. guianensis oil had an anthelmintic efficacy of 91.4% against monogeneans. There was increase of total plasma protein and glucose, number of erythrocytes, thrombocytes, leukocytes, lymphocytes and number of monocytes and decrease in mean corpuscular volume. Histological changes such as epithelium detachment, hyperplasia, lamellar fusion and aneurysm were found in the gills of tambaqui from all treatments, including controls with water of culture tank and water of culture tank plus iso-propyl alcohol. Therapeutic baths with 500 mg/L of C. guianensis oil showed high efficacy and caused few physiological changes capable of compromising fish gill function. Results indicate that C. guianensis oil has an anthelmintic potential for control and treatment of infections by monogeneans in tambaqui.

Trichoderma asperellum Extract Isolated from Brazil Nuts (Bertholletia excelsa BONPL): In Vivo and In Silico Studies on Melanogenesis in Zebrafish.

Endophytic fungi are those that present part of their life cycle in healthy tissues of different plant hosts in symbiosis without causing harm. At the same time, fungus-plant symbiosis makes it possible for microorganisms to synthesize their own bioactive secondary metabolites while in the stationary stage. To accomplish this, the endophytic fungus Trichoderma asperellum was isolated from Bertholletia excelsa (Brazil nut) almonds. The fungus was cultivated and extracted with ethyl acetate, obtaining AM07Ac. Then, using HPTLC (High-performance thin-layer chromatography) and nuclear magnetic resonance (1H NMR), ß-amyrin, kaempferol, and brucine were identified as major compounds. Further in vivo assays in zebrafish demonstrated the activity of AM07Ac on melanogenesis by producing a concentration-response inhibitory effect, which, through an in silico study, proved to be related to the noted major compounds known to inhibit tyrosinase activity. The inhibition of tyrosinase prevents melanin accumulation in skin. Therefore, these results imply the importance of investigating microorganisms and their pharmacological activities, in particular the endophytic fungus Trichoderma asperellum as a generator of active metabolites for melanogenesis modulation.

Copper-Contaminated Substrate Biosorption by Penicillium sp. Isolated from Kefir Grains.

In this bioremediation study, the fungus Penicillium sp. isolated from kefir grains was evaluated for its resistance to copper in the culture medium. Penicillium sp. was cultivated in liquid medium prepared using 2% malt-agar at pH 7.0. Biomass of the fungus was significantly reduced, but only when 800 mg·L-1 of Cu(NO3)2 copper nitrate was used. The effect on radial growth of the fungus in experiments combining different pH values and the inorganic contaminant showed an inhibition of 73% at pH 4.0, 75% at pH 7.0 and 77% at pH 9.0 in liquid medium. Thus, even though the growth of Penicillium sp. could be inhibited with relatively high doses of copper nitrate, images obtained with scanning electron microscopy showed the preservation of fungal cell integrity. Therefore, it can be concluded that Penicillium sp. isolated from kefir grains can survive while performing bioremediation to minimize the negative effects of copper on the environment through biosorption.

Assessment of the hypoglycemic effect of Bixin in alloxan-induced diabetic rats: in vivo and in silico studies.

The objectives of this study were to extract and purify Bixin from the seeds of Bixa orellana and to evaluate its hypoglycemic activity in vivo, as well as, to conduct an in silico study of selectivity on peroxisome proliferator-activated receptors via molecular docking and molecular dynamics simulations. Oral administration of Bixin (10 mg/kg) significantly reduced their glucose level that was alloxan-induced diabetic rats. Bixin showed in silico selectivity on peroxisome proliferator-activated receptors (PPARs), particularly by the peroxisome proliferator-activated receptor gamma (PPARγ), which supports the hypoglycemic activity of Bixin. From the results obtained, it can be inferred that Bixin presents hypoglycemic characteristics, which was confirmed by the results obtained from the in vivo and in silico tests. Bixin may act by other pathways to control blood glucose and thus it is possible that it presents a different toxicity profile than troglitazone, rosiglitazone and pioglitazone. However, more studies on the activity and toxicity of Bixin are needed to evaluate for further clinical use. Communicated by Ramaswamy H. Sarma.

Acmella oleracea (L) R. K. Jansen Reproductive Toxicity in Zebrafish: An In Vivo and In Silico Assessment.

The plant species Acmella oleracea L. is used in the north of Brazil for the treatment of a range of illnesses, such as tuberculosis, flu, cough, and rheumatism and as an anti-inflammatory agent; besides, hydroethanolic formulations with this species are popularly used as a female aphrodisiac agent. However, currently, there are no studies performed evaluating its effect on embryonic development. Hence, this research aimed to evaluate the effects of the hydroethanolic extract of A. oleracea (EHFAo) on the reproductive performance (parental) and embryonic development (F1 generation) of zebrafish, at concentrations of 50, 100, and 200 µg/L. Histopathology of parental gonads after 21 days of exposure to EHFAo reveals few alterations in the ovaries and testes, not impairing the reproduction; an increase of eggs deposition was observed in animals treated with EHFAo at the highest concentrations. Nevertheless, concerning the embryonic development of F1, teratogenic effects were observed including tail deformation, cardiac and yolk edema, scoliosis, and growth retardation; these alterations were more prominent in the groups born from progenitors exposed to the highest concentrations (100 and 200 µg/L.); but only the occurrence of yolk and cardiac edema had a statistically significant difference when compared to the control group. The chromatographic analysis shows that spilanthol (affinin) was the primary compound found in the EHFAo. Hence, in silico assessment was performed to evaluate the pharmacokinetic and toxicological properties of this molecule and 37 metabolites derived from it. Overall, our data show that the treatment caused no detrimental changes in progenitors regarding their gonads or fertility but caused some potentially teratogenic activity in embryos, which may be due to the action of spilanthol's metabolites M3, M6, M7, M8, M16, M28, and M31.

Action of the hydroethanolic extract of the flowers of Acmella oleracea (L.) R.K. Jansen on the reproductive performance of Wistar females rats: A popular female aphrodisiac from the Amazon.

ETHNOPHARMACOLOGICAL RELEVANCE: The species Acmella oleracea (L.) R.K. Jansen (Asteraceae), popularly known as jambú, is marketed in fairs as a female aphrodisiac and has several pharmacological activities already confirmed, among them the sexual stimulant action. The objective of this study was to evaluate the effects of the oral administration of the hydroethanolic extract of A. oleracea flowers (EHAo) on wistar rats during the pre-mating, mating, and pre-implantation period. MATERIAL AND METHODS: During the treatment period, measurements of feed intake, water intake, weight, estrous cycle, behavior, reproductive parameters, biochemical parameters, hematological parameters, and histopathology of ovaries were performed daily. RESULTS: In the gas chromatography analysis - mass spectrometry characterization, the compound (2E, 6Z, 8E) -N-isobutyldeca-2,6,8-trienamide (spilanthol) was detected as the majority compound at the 84% concentration. In the conditions of this study, EHAo did not cause maternal toxicity. However, in the estrous cycle, the frequency of the Proestrous (P) and Estrous (E) phase was significantly increased with the doses of 88.91 and 444.57mg/kg of the EHAo in relation to the control. On the other hand, the metaestrous (M) and diestrous (D) phases showed a significant reduction in their frequency in the groups treated with EHAo. Water intake increased significantly (p < 0.01), as well as the triglyceride levels, the total cholesterol and fractions (p < 0.05), and the percentage of neutrophils (p < 0.05). CONCLUSION: It is concluded, therefore, that the treatment with EHAo, which is one of the forms popularly used, is safe in the concentrations and time of treatment studied as it is able to influence the estrous cycle without altering folliculogenesis and fertility.

Effect of Euterpe oleracea Mart. (Açaí) Oil on Dyslipidemia Caused by Cocos nucifera L. Saturated Fat in Wistar Rats.

Dyslipidemia is caused by disturbances in lipid metabolism that lead to chronic elevations of serum lipids, especially low-density lipoprotein (LDL)-cholesterol and triglycerides, increasing the risk of metabolic syndrome, obesity, diabetes, atherogenic processes, and cardiovascular diseases. The oil from the fruits of Euterpe oleracea (OFEO) is rich in unsaturated fatty acids with potential for treating alterations in lipid metabolism. In this study, we aimed to investigate the effect of OFEO on hyperlipidemia induced by Cocos nucifera L. saturated fat (GSC) in Wistar rats. Chromatographic profile showed that unsaturated fatty acids account for 66.08% in OFEO, predominately oleic acid (54.30%), and saturated fatty acids (palmitic acid 31.6%) account for 33.92%. GSC-induced dyslipidemia resulted in an increase in total cholesterol, LDL-cholesterol, triglycerides, glucose, and liver and abdominal fat, as well as atherogenic processes in the thoracic aorta. OFEO treatment did not reduce hypertriglyceridemia, but did reduce total cholesterol and LDL-cholesterol, thus contributing to the antiatherogenic action of OFEO. OFEO treatment inhibited the formation of atheromatous plaques in the vascular endothelium of the treated rats, as well as those who were treated with simvastatin. The results obtained suggest that OFEO has an antiatherogenic effect in a rat model of dyslipidemia.

Effect of the treatment of Copaifera duckei oleoresin (copaiba) in streptozotocin-induced diabetic rats

ABSTRACT Diabetes mellitus is a syndrome that reaches more than 382 million people worldwide. It interferes with the metabolism of carbohydrates, causing chronic hyperglycemia. The objective of this study was to evaluate the effect of the Copaifera duckei, Dwyer, Fabaceae, oleoresin on streptozotocin-induced (STZ) diabetic rats. This study was based on the induction of diabetes mellitus by streptozotocin (55 mg/kg, i.p.) in Wistar rats and treated with doses of C. duckei oleoresin (250 and 500 mg/kg, p.o.). Subsequently, the clinical, biochemical and histopathological of the pancreas parameters were evaluated. Gas chromatographic analysis indicated that β-bisabolene (22.29%), β-caryophyllene (21.25%) and α-farnesene (15.58%) sesquiterpenes were the major components of the C. duckei oleoresin. In streptozotocin-induced diabetes mellitus, it was possible to observe that the C. duckei oleoresin treatment had a significant effect (p < 0.001) on the clinical parameters, and that there was a positive improvement. This was attenuated by the urea, creatinine, and transaminases alterations (p < 0.001) observed in animals with diabetes mellitus, as well as the significantly reduced (p < 0.001) values of total cholesterol, triacylglycerides, and glucose. In the histopathological analyses of the pancreas, it was observed that the C. duckei oleoresin was able to restore β-cells and to significantly increase the quantity and diameter of the Langerhans islets (p < 0.05), when compared to the diabetic group. The treatment with C. duckei oleoresin, employed under the conditions of this study, presented antidiabetic activity and can improve the complications found in this syndrome.