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

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

Determination of preclinical safety of oil obtained from Pachira aquatica Aublet (Malvaceae) seeds: histopathological, biochemical, hematological, and genetic toxicity studies in rats.

Pachira aquatica is a species used for medicinal and food purposes and has numerous phytochemicals that may have systemic toxic effects and damage to genetic material. This study aimed to evaluate acute and short-term oral toxicity, as well as genotoxic and clastogenic effects of oil extracted from P. aquatica (PASO) seeds in rats and Drosophila melanogaster. The results obtained with biochemical and hematological analyses did not show significant changes in any evaluated parameters when compared with reference values for the species used in the study. Data from the histopathological analysis corroborated results found in this study. These findings indicate low acute and short-term toxicity following oral PASO exposure in rats under the experimental conditions tested. Tests performed in rats showed that PASO did not present significant genotoxic or clastogenic effects on the cells analyzed with the three doses tested. Treatment with PASO in the offspring of HB crossing, which showed high cytochrome P450 levels, did not exhibit genotoxic activity, as demonstrated by the SMART test. These results suggest that products from the hepatic oil metabolism did not show genotoxicity under the conditions tested. Together, the results indicate that, under the experimental conditions tested, PASO is safe for repeated intake. As PASO exhibited low potential to cause harmful effects on living organisms, our study encourages further research aimed at assessing its pharmacological activity, since it is a widely consumed plant.

Evaluation of embryotoxic and teratogenic effects of the oil extracted from Caryocar brasiliense Cambess pulp in rats.

The objective of this study was to evaluate the maternal, embryotoxic and teratogenic effects of Caryocar brasiliense pulp oil (OPCB), oil widely used in Brazilian cuisine and traditional medicine. Pregnant Wistar female rats were used in this study for three treatment groups (250, 500 and 1000 mg/kg/day) and a control group. The OPCB was administered orally throughout the period of organogenesis of females (6th until the 15th day of gestation). The pregnant females were gross necropsied on d20, followed by maternal and fetus examination, to evaluate the teratogenicity, reproductive and developmental performance of OPCB. The results showed there was no significant statistical difference in the ponderal evolution of the pregnant females, as well as in the behavioral, hematological, biochemical or histopathological data, indicating the absence of maternal toxicity of the oil. The mean number of corpora lutea, implantation and resorption sites, as well as all calculated reproductive rates, also remained statistically similar between the groups, indicating low embryotoxic effects of the tested plant specie. In fetal examination, external anomalies and skeletal abnormalities were observed in all treated and control groups. The NOAEL for maternal toxicity and embryo/fetal development for the OPCB administered by gavage, was 1000 mg/kg/bw/day.

Safety Assessment of Oil from Pequi (Caryocar brasiliense Camb.): Evaluation of the Potential Genotoxic and Clastogenic Effects.

Genotoxic data of medicinal plants and functional foods are required as part of the risk assessment by international regulatory agencies. Due to its food consumption and ethnopharmacological relevance, pequi oil (Caryocar brasiliense Camb.) is one of these compounds to be studied. The aim of this study was to evaluate the cytotoxic, genotoxic, and clastogenic effects of the oil from the pulp of C. brasiliense (OPCB) in vivo and in vitro. Initially, the Artemia salina in vitro assay was conducted to determine the cells viability rate of different doses of the OPCB. Subsequently, comet assay (Organization for Economic Cooperation and Development, OECD 489) and micronucleus test (OECD 474) were performed in blood and bone marrow of Wistar rats treated orally with a 125, 250, 500, or 1000 mg/kg/bw of the OPCB for 4 weeks. The chemical analysis indicated the presence of ß-carotene and lycopene in the oil. In the A. salina test, all OPCB doses maintained cell viability rates statistically similar to the negative control. The in vivo tests performed showed that OPCB did not show significant genotoxic or clastogenic effects in cells analyzed with the four doses tested. Altogether, these results indicate that, under our experimental conditions, C. brasiliense fruit oil did not reveal genetic toxicity in rat cells.