Anti-hyperglycemic potential and chemical constituents of Aristolochia triangularis Cham. leaves - A medicinal species native to Brazilian forests.

ETHNOPHARMACOLOGICAL RELEVANCE: Aristolochia triangularis Cham. has been used in Brazilian traditional medicine for various therapeutic purposes, including as a leaf-based infusion for diabetes management. AIM OF THE STUDY: This study was designed to chemically characterize an infusion of in natura A. triangularis leaves and evaluate the in vivo anti-hyperglycemic properties of this infusion. MATERIALS AND METHODS: Chemical composition was examined using liquid-liquid extraction procedure, chromatographic methods, NMR, and LC-MS/MS. The in vivo anti-hyperglycemic activity of the freeze-dried infusion of A. triangularis leaves (Inf-L-At) was assessed using oral glucose tolerance test (OGTT). Initially, normoglycemic male rats were pre-treated with orally administered Inf-L-At at doses of 62.5, 125, and 250 mg/kg for two consecutive days. On the day of the OGTT, fasting animals received a glucose load (4 g/kg) 30 min after treatment with Inf-L-At, and the blood glucose levels were verified at 15, 30, 60, and 180 min. Intestinal maltase, lactase, and sucrase activities and muscle and liver glycogen contents were also assessed after the OGTT. RESULTS: Inf-L-At extract led to glycemic reduction with no dose-response at 15, 30, and 60 min comparable to that of the antidiabetic drug glibenclamide and was accompanied by an increase in hepatic and muscle glycogen contents. Additionally, there was a significant statistically decrease in the in vitro activity of disaccharidases. Maltase and sucrase activities were inhibited at all doses, whereas lactase activity was inhibited only at 62.5 and 250 mg/kg. In total, 75 compounds were found in the infusion, including seven new ones, (7S*,8S*,7ꞌS*,8ꞌR*)-4,4ꞌ-dihydroxy-3,3ꞌ-dimethoxy-7,9ꞌ-epoxylignan-7ꞌ-ol; 4ꞌ-hydroxy-3ꞌ-methoxy-3,4-methylenedioxy-7,9ꞌ-epoxylignan-9,7ꞌ-diol; triangularisines A, B, and C; N-ethyl-N-methyl-affineine; and N-methyl pachyconfine, and one previously not described as a natural product, epi-secoisolariciresinol monomethyl ether. CONCLUSION: The results demonstrated the anti-hyperglycemic activity of the infusion from A. triangularis leaves and showed that it is a rich source of lignoids, alkaloids, and glycosylated flavonoids, which are known to exhibit antidiabetic effects and other biological properties that can be beneficial for patients with chronic hyperglycemia, thus certifying the popular use of this herbal drink.

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.

Cytotoxicity, mutagenicity and acute oral toxicity of aqueous Ocotea minarum leaf extracts.

Ocotea minarum (Nees & Mart.) Mez., a native species of Brazil, is used in the treatment of infections and oxidative stress; however, there is no scientific evidence of its toxicological characteristics. We assessed the cytotoxicity, mutagenic activity, and acute oral toxicity of the aqueous extract isolated from O. minarum leaves. The cytotoxicity of this extract was evaluated in tumour and non-tumour cell lines, while the Ames test with a Salmonella Typhimurium was used to determine the mutagenic activity. Wistar rats received a single 2 g/kg dose as part of an LD50 toxicity assessment. Our results showed that the aqueous extract of O. minarum leaves did not present cytotoxic and mutagenic properties and was not toxic, with an LD50 greater than 2 g/kg. Therefore, the O. minarum extracts are pharmacologically safe and can continue to be investigated for the development of new drugs and herbal medicines.

General and genetic toxicology studies of Aleurites moluccana (L.) Willd. seeds in vitro and in vivo assays.

ETHNOPHARMACOLOGY RELEVANCE: Aleurites moluccana is popularly used for the diseases like ulcers, fever, headache, asthma, conjunctivitis, gonorrhea, inflammation, hepatitis, and rheumatism. The seed, also known as "noz da Índia", has been popularly consumed for weight loss purposes but reports of toxicity have been associated with its ingestion. In the literature, there are not enough studies to elucidate its toxicology, so evaluating the general and genetic toxicological of A. moluccana seeds can provide data to ensure their intake. AIM OF THE STUDY: The objective of the present study was to elucidate the oral toxicity, mutagenicity, genotoxicity and cytotoxicity of A. moluccana seeds in vitro and in vivo assays. MATERIALS AND METHODS: The chemical composition of the aqueous extract of A. moluccana seeds (AEAMS) was analyzed in relation to phenolic compounds, tannins, flavonoids and fatty acid. For the in vitro assays, the cytotoxic potential was assessed by the MTS assay whereas the mutagenic potential was assessed by the Ames test. For in vivo assays, was conducted an acute oral toxicity study, with "Up-and-Down Procedure" and repeated dose toxicity with "Repeated Dose 28-Day Oral Toxicity". To assess genetic damage, mutagenic potential was assessed by the micronucleus test whereas the polychromatic erythrocyte/normochromatic erythrocyte ratio was obtained with bone marrow cells to determine the cytotoxic potential and genotoxic potential was assessed by the comet assay using peripheral blood cells. RESULTS: AEAMS did not show cytotoxic and mutagenic potential in vitro. No clinical signs of toxicity were observed in animals after the acute oral toxicity test, suggesting that the LD50 of aqueous extract of A. moluccana seeds > 2000 mg/kg in a single dose by intragastric route. However, in toxicity at repeated doses for 28 days, the doses initially established (250; 500 and 750 mg/kg/day by intragastric route) caused mortality in the animals and the reestablished doses (25, 50 and 100 mg/kg/day by intragastric route) showed no changes in parameters or clinical signs attributed to toxicity. Furthermore, AEAMS also did not show mutagenic, genotoxic and cytotoxic potential in vivo. CONCLUSIONS: AEAMS did not show cytotoxic, genotoxic and mutagenic potential in vitro and in vivo. And although the AEAMS has an LD50 > 2000 mg/kg, and does not have physiological, biochemical, hematological, histopathological changes or clinical signs related to toxicity when administered in low concentrations and for a short period, in high concentrations and continued use caused toxicity and mortality in Wistar rats. In order to obtain complementary results, is recommended highly that further mid and long-term toxicological studies are investigated, and in no-rodent specie.

Evaluation of the toxic potential of the aqueous extract from Mangifera indica Linn. (Anacardiaceae) in rats submitted to experimental models of acute and subacute oral toxicity.

ETHNOPHARMACOLOGICAL RELEVANCE: The population has traditionally used the Mangifera indica plant leaves to treat diseases such as Diabetes Mellitus and alleviate signs and symptoms such as inflammation, diarrhea, and dysentery. In a previous study, we demonstrated that the flavonoids present in the aqueous extract from M. indica leaves (EAMI) exhibited a potent hypoglycemic effect in diabetic rats, promoting the widespread use of the plant by the population and highlighting the importance of investigating its oral toxicity. AIM OF THE STUDY: The present study aimed to assess the toxic potential of EAMI in rats submitted to experimental models of acute and subacute (short-term) oral toxicity. MATERIAL AND METHODS: For the acute toxicity test, female Wistar rats received a single oral dose of 2000 mg/kg body weight of EAMI and were observed for 14 days. In the short-term toxicity test, male and female Wistar rats received repeated oral EAMI doses of 125, 250, 500 or 1000 mg/kg body weight and observed for 28 days. RESULTS: The phytochemical analysis of EAMI demonstrated that the extract has high levels of flavonoids. No animals died in the acute toxicity test, and no clinical changes were observed that show signs of toxicity in the animals. There was no significant change in the weight of the organs of the animals submitted to tests with the EAMI, suggesting that LD50 is greater than 2000 mg/kg. In the conditions and doses tested in the short-term toxicity experiments, the treatment did not produce significant changes in the physiological, biochemical, hematological, and histopathological parameters in the animals evaluated. CONCLUSIONS: Our study demonstrated that high doses of EAMI administered acutely, as well as all doses evaluated in the short-term oral toxicity model, should be considered safe during traditional therapeutic use.

From general toxicology to DNA disruption: A safety assessment of Plinia cauliflora (Mart.) Kausel.

ETHNOPHARMACOLOGICAL RELEVANCE: Plinia cauliflora (Mart.) Kausel (Myrtaceae) is popularly known as "jaboticaba" or "jaboticaba". The fruit is appreciated for both fresh consumption and the manufacture of jelly, juice, ice cream, fermented beverages, and liqueurs. The more widespread traditional use of the plant involves the treatment of diarrhea, which utilizes all parts of the plant, including the fruit peels. AIM OF THE STUDY: We sought to elucidate possible risks of the administration of an ethanol-soluble fraction that was obtained from an infusion of P. cauliflora fruit peels (SEIPC). We performed a series of experiments to evaluate possible toxicity, in which we administered SEIPC orally both acutely and repeatedly for 28 days. We also evaluated possible endocrine-disruptive and genotoxic effects in eukaryotic cells. The possible mutagenic activity of SEIPC was evaluated using reverse mutation (Ames) assays. MATERIALS AND METHODS: SEIPC was produced and chemically characterized by LC-DAD-MS. Acute toxicity and behavioral and physiological alterations were evaluated in the modified Irwin test. Respiratory rate, arterial blood gas, electrocardiography, respiratory rate, heart rate, and blood pressure were evaluated, and hematological, biochemical, and histopathological analyses were performed after 28 days of oral treatment. The comet assay, mammalian erythrocyte micronucleus test, uterotrophic test, Hershberger bioassay, and AMES test were performed using appropriate protocols. RESULTS: From SEIPC, ellagic acid and derivatives, flavonols and anthocyanidins, as well as citric acid and gallic acid, were annotated by LC-DAD-MS. We did not observed any significant toxic effects after acute or prolonged SEIPC treatment. No endocrine-disruptive or mutagenic effects were observed. CONCLUSIONS: The present study found that SEIPC did not cause any significant alterations of various corporeal systems, including cardiac electrical activity, body temperature, respiratory rate, and arterial pressure. No alterations of biochemical, hematological, or blood gas parameters were observed. SEIPC did not cause any perturbations of the endocrine system or mutagenic, cytotoxic, or genotoxic effects. These findings substantiate the safe clinical use of P. cauliflora.

Aqueous extract from Mangifera indica Linn. (Anacardiaceae) leaves exerts long-term hypoglycemic effect, increases insulin sensitivity and plasma insulin levels on diabetic Wistar rats.

BACKGROUND: Diabetes mellitus is one of the most common todays public health problems. According to a survey by the World Health Organization, this metabolic disorder has reached global epidemic proportions, with a worldwide prevalence of 8.5% in the adult population. OBJECTIVES: The present study aimed to investigate the hypoglycemic effect of aqueous extract of Mangifera indica (EAMI) leaves in streptozotocin-induced diabetic rats. METHODS: Sixty male rats were divided into 2 groups: Normoglycemic and Diabetic. Each group was subdivided into negative control, glibenclamide 3 or 10 mg/kg, EAMI 125, 250, 500, and 1000 mg/kg. Intraperitoneal injection of streptozotocin 100 mg/kg was used to DM induction. The hypoglycemic response was assessed acutely after two and four weeks of treatment. After a 6-hour fasting period, the fasting blood glucose of animals was verified, and 2.5 g/kg glucose solution was orally administered. The insulin tolerance test and plasma insulin levels assessment were performed in the morning after fasting of 12 to 14 hours. RESULTS AND CONCLUSION: The chemical analysis of EAMI showed high levels of phenolic compounds. There was no significant difference in fasting blood glucose between normoglycemic and diabetic groups, and that EAMI did not have an acute effect on diabetes. After two and four weeks of treatment, the extract significantly reduced blood glucose levels, exceeding glibenclamide effects. EAMI was effective in maintaining the long-term hypoglycemic effect, as well as, significantly increased the sensitivity of diabetic animals to insulin and the plasma insulin level.

Cytotoxic, genotoxic and mutagenic evaluation of Alibertia edulis (rich.) a. Rich. ex DC: an indigenous species from Brazil.

Tea leaves of Alibertia edulis is popularly used in folk medicine. However, studies on the genotoxicity of this plant are not available. We aimed to investigate the in vivo and in vitro cytotoxic, genotoxic and mutagenic potentials of the aqueous extract of A. edulis leaves (AEAE). Antioxidant assays, the Artemia salina test, MTT in human platelets, micronucleus in bone marrow and comet in peripheral blood were performed. Animals received four different doses of the AEAE by oral gavage for 30 days. Saline and cyclophosphamide were used as controls. The AEAE exhibited a maximal inhibition at 100 and 250 µg/mL, according to the ABTS and DPPH methods, respectively. The A. salina assay showed that the AEAE presented some toxicity at doses of 100, 250 and 500 µg/mL. Through the MTT assay, the AEAE showed no toxic effects on human platelets during the incubation period. The alkaline comet assay showed that all doses of the AEAE were statistically similar to the negative control group since they did not induce any significant increase of the overall number of damaged cells nor the severity of the cell damage. In the micronucleous assay, results demonstrate that the AEAE did not increase the production of micronucleated polychromatic erythrocytes and was statistically similar to the negative control. The four doses of the plant extract did not affect the production of new erythrocytes and were statistically similar to the negative control groups. Furthermore, the AEAE demonstrated no cytotoxicity, genotoxicity and mutagenicity at the doses tested in rats.

The ethanolic extract obtained from Campomanesia pubescens (D.C.) O.BERG fruits exerts anxiolytic and antidepressant effects on chronic mild stress model and on anxiety models in Wistar rats: Behavioral evidences.

Objectives: Campomanesia pubescens (DC) O.BERG (Myrtaceae) fruits contain high levels of flavonoids and are widely consumed by the South American population. In the central nervous system (CNS), some flavonoids act as modulators of GABA-A receptors and monoamine oxidase inhibitors, resulting in anxiolytic antidepressants effects, respectively. The objective of the present study was to evaluate the anxiolytic and antidepressant effects of ethanolic extract of C. pubescens fruits (EEFCP) in rats.Methods: In order to prove the antidepressant effect of the EEFCP, rats were submitted to the chronic mild stress model, to the sucrose preference test (SPT), and the forced swimming test. To test the anxiolytic effects, the Elevated plus-maze (EPM), open field (OF), and Marble-Burying models were used.Results: After 2 weeks of treatment, imipramine 25 mg/kg, EEFCP 250 mg/kg, and EEFCP 500 mg/kg reversed the anhedonic behavior measured by SPT and significantly reduced the immobility time of animals under stress. In addition, treatment with diazepam 2 mg/kg, EEFCP 250 mg/kg, and EEFCP 500 mg/kg increased the percentage of entries and time spent on the open arms of the EPM, increased locomotion, rearing, and reduced the grooming time in OF.Discussion: The chemical analysis of the EEFCP indicated high content of flavonoids and the behavioral analysis revealed an antidepressant and anxiolytic effect, suggesting that these phytochemicals may be involved with these actions in the CNS.

Preclinical safety evaluation of the aqueous extract from Mangifera indica Linn. (Anacardiaceae): genotoxic, clastogenic and cytotoxic assessment in experimental models of genotoxicity in rats to predict potential human risks.

ETHNOPHARMACOLOGICAL RELEVANCE: Medicinal plants widely used by the population contain significant concentrations of biologically active compounds and, although they have proven pharmacological properties, can cause DNA damage and develop fatal diseases. AIM OF THE STUDY: The present study aimed to evaluate the genotoxic, cytotoxic potential and clastogenic effects of the aqueous extract from Mangifera indica leaves (EAMI) on rats submitted to experimental genotoxicity models and through the SMART test performed in Drosophila melanogaster. MATERIAL AND METHODS: The comet assay and the micronucleus test were performed on peripheral and bone marrow blood, respectively, of Wistar rats, orally treated with EAMI at doses of 125, 250, 500 and 1000 mg/kg/bw for 28 days. In the SMART test, the standard cross between three mutant D. melanogaster strains was used. Larvae were treated with EAMI at different concentrations, and the wings of adult flies were evaluated for the presence/frequency of mutant spots and compared to the negative control group. RESULTS: Phytochemical analysis of EAMI indicated high levels of flavonoids. The tests performed in rats showed that EAMI did not present significant genotoxic or clastogenic effects. The results showed a critical dose-dependent cytoprotective effect exerted by EAMI. This result was attributed to the high content of polyphenols and flavonoids. The biotransformation metabolites of EAMI did not present genotoxic activity, as demonstrated by the SMART test. CONCLUSIONS: These results are relevant since they provide safety information about a plant species of great therapeutic, economical, nutritious and ethnopharmacological value for the population.

Preclinical safety evaluation of the ethanolic extract from Campomanesia pubescens (Mart. ex DC.) O.BERG (guavira) fruits: analysis of genotoxicity and clastogenic effects.

Genotoxicity studies of plants with medicinal and nutritional properties are recommended by international regulatory agencies as part of the risk assessment. Due to their consumption as food, nutraceutical use and ethnopharmacological relevance, Campomanesia pubescens represents one of these plants to be studied. The aim of the present study was to evaluate the genotoxic, cytotoxic potential and clathogenic effects of the ethanolic extract obtained from the pulp of C. pubescens (EEFCP) fruits on rats submitted to experimental genotoxicity models and through the SMART test performed in Drosophila melanogaster. The comet assay and the micronucleus test were performed on peripheral and bone marrow blood, respectively, of Wistar rats orally treated with EEFCP at doses of 125, 250, 500 and 1000 mg per kg per bw for 28 days. In the SMART test, the standard cross between three mutant D. melanogaster strains was used. Larvae were treated with EEFCP at different concentrations and the wings of adult flies were evaluated for the presence/frequency of mutant spots and compared to the negative control group. Phytochemical analysis of EEFCP indicated high levels of flavonoids. The tests performed in rats showed that EEFCP did not present significant genotoxic or clastogenic effects. The biotransformation metabolites of EEFCP did not present genotoxic activity, as demonstrated by the SMART test. Together, all results indicate that, under the experimental conditions used, EEFCP did not reveal any preclinical genetic toxicity. Therefore, the safe consumption can be fomented increasing, consequently, the economic liquidity in the industrial market from the fruits of guavira.

Preclinical safety evaluation of the ethanolic extract from guavira fruits (Campomanesia pubescens (D.C.) O. BERG) in experimental models of acute and short-term toxicity in rats.

Campomanesia pubescens is a fruit plant widely distributed in South America and used by the population for medicinal and nutritional purposes, with important economic and cultural value. This study evaluated the toxic potential of the ethanolic extract from C. pubescens (EEFCP) fruits through acute and short-term toxicity tests. For the acute toxicity test, female rats received a single oral dose of 2000 mg/kg body weight of EEFCP and were observed for 14 days. In the short-term toxicity test, male and female rats received repeated oral doses of 125, 250, 500 or 1000 mg/kg of EEFCP, being treated and observed for 28 days, and after the treatment period, a satellite and satellite control group remained under observation for another 14 days. No mortality, clinical and organ weight alterations were observed, indicating that LD50 is greater than 2000 mg/kg body weight. In addition, the doses tested did not produce significant changes in the behavioral, physiological, hematological or histopathological parameters of animals. These results demonstrate the low acute and short-term toxicity of EEFCP in rats. The data obtained are of great relevance since they provide important information about a plant species of great economic, nutritional and ethnopharmacological value.

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.

Safety Assessment and Botanical Standardization of an Edible Species from South America.

Tropaeolum majus L. (Tropaeolaceae), commonly known as nasturtium, is an important edible plant native to the Andean States and widely disseminated throughout South America. Despite the use of this species is quite widespread, there are no minimum quality control standards or data on its genotoxicity. So, the aim of this study was to present a detailed anatomical and histochemical study for Tropaeolum majus and provide genotoxicity parameters of a preparation routinely used in South American countries. First, three different Tropaeolum majus aqueous extracts (TMAEs) at concentrations of 1.5%, 7%, and 15% were prepared according to the popular use. Then, genetic toxicity of TMAE was evaluated on bacterial reverse mutation, genomic lesions, and micronucleus formation in male rats. Furthermore, a detailed anatomical and histochemical study of the leaves and stems of Tropaeolum majus were performed. No revertant colonies were found in any bacterial cultures examined. In the comet assay, TMAE showed no significant DNA damage in all tested doses. Micronucleus assay showed no significant increases in the frequency of inducing micronuclei in any dose examined. Light and electron microscope images of cross-section of leaves and stems from Tropaeolum majus revealed useful diagnostic features. The presented data showed significant safety parameters for the use of TMAE and provided important data for the quality control of this plant species.

Acute and subacute oral toxicity assessment of the oil extracted from Attalea phalerata Mart ex Spreng. pulp fruit in rats.

Attalea phalerata Mart. ex Spreng., popularly known as "bacuri", is a native plant from the brazilian Cerrado and used in folk medicine as a pulmonary decongestant, an anti-inflammatory for joints and antipyretic. There is an expectation about the use in chronic disease of the Attalea phalerata oil since its composition is high in carotenoids and beneficial fatty acids. The aim of the study was to evaluate the toxicological profile of the oil extracted from Attalea phalerata Mart. ex Spreng. pulp (APO). Acute and subacute toxicity studies were performed in male and female Wistar rats according to the OECD - Guidelines 425 and 407. For the acute toxicity, one single dose of the APO (2000mg/kg) was administered by gavage to five female rats. In the subacute toxicity, four different doses (125, 250, 500 and 1000mg/kg) of the APO were administered to male and female rats for 28 consecutive days. No deaths or behavioral changes were observed during both experiments as well as no changes in organ weights, hematological, histopathological parameters. The biochemical parameters showed changes in phosphatase alkaline and albumin levels, however these values are within the normal range for the species. A significant reduction in cholesterol and triglycerides was also observed in some of the animals treated with the APO. Therefore, the LD50 is higher than 2000mg/kg and the APO oil can be considered safe at the doses tested in rats. However, further assessments are required in order to proceed to clinical studies in humans.

Acute and subacute toxicity of the aqueous extract of Alibertia edulis (Rich.) A. Rich. ex DC. in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Alibertia edulis, popularly known as "marmelo do Cerrado" is a native plant from the brazilian Cerrado. It has high food and ornamental potential and the tea leaves are currently used as hypoglycemic, antihypertensive and diuretic. AIM OF THE STUDY: In order to evaluate the safety of the aqueous extract of Alibertia edulis leaves (AEAE), the acute and subacute toxicity tests were performed in male and female Wistar albino rats. MATERIALS AND METHODS: The experiments were performed in accordance with the OECD guidelines 425 and 407. For the acute toxicity, one single dose of the AEAE (2000mg/kg) was administered by gavage to five female rats. The animals were observed for 14 days for any signs of toxicity and death. In the subacute toxicity, four different doses (125, 250, 500 and 1000mg/kg) of the AEAE were administered to male and female rats for 28 consecutive days. A satellite group received the maximum dose (1000mg/kg) for 28 days and remained untreated for 14 more days in order to observe reversibility, persistence, or delayed occurrence of toxic effects. The five parameters of the Hippocratic screening, body weight, food and water intake were daily observed. At the end of the experiment, blood samples were collected for the hematological and biochemical analysis. The vital and reproductive organs were inspected for any histopathological changes. RESULTS: No deaths or behavioral changes were observed during both experiments as well as no changes on organ weights, biochemical, hematological and histopathological parameters that could indicate any signs of toxicity. CONCLUSION: All doses tested can be considered safe in rats and the LD50 is higher than 2000mg/kg. Therefore, further assessments are required in order to proceed to clinical studies in humans.

Study on the Cytotoxic, Genotoxic and Clastogenic Potential of Attalea phalerata Mart. ex Spreng. Oil Pulp In Vitro and In Vivo Experimental Models.

Attalea phalerata Mart. ex Spreng. (Arecaceae), popularly known as "bacuri", is used in Brazilian folk medicine. Its oil is used orally to relieve pulmonary congestion and joint pain. In topical applications, it is applied as an effective hair tonic and anti-dandruff. The in natura pulp and its nuts are used as food because of its nutritional value. Despite its use in folk medicine, there is a lack of data regarding its in vivo/in vitro cytotoxic/genotoxic and clastogenic effects. Therefore, in this study, we evaluated the cytotoxic, genotoxic and clastogenic effects of Attalea phalerata Mart. ex Spreng. oil (APMO) in vitro and in vivo. For the analysis of cytotoxic potential, the Artemia salina and MTT (3-(4,5-dimethizzol-zyl)-2,5-diphenyltetrazolium bromide) assays were performed. Possible cytotoxic, genotoxic and clastogenic effects of APMO intake were determined by performing the comet and micronucleus assays. Male and female Wistar rats were orally treated with doses of 125, 250, 500 or 1000 mg.kg-1 of the APMO daily for 28 consecutive days (four weeks). The results showed that the APMO did not induce cell death in the experiments of Artemia salina and MTT, indicating that it has no cytotoxicity. The APMO did not cause significant damage to the DNA of the rats in the four doses used when compared to the negative control group (saline + Tween® 80). The APMO did not present any significant increase in micronucleated polychromatic erythrocytes (MNPCEs) for the four tested doses. When compared to the positive control group, all groups (comet and micronucleus tests) were statistically different. These data suggest that the administration of Attalea phalerata Mart oil. ex Spreng does not cause cytotoxicity, genotoxicity and clastogenicity in experimental models in vitro and in vivo following oral administration in this study.

Oral acute and subchronic toxicity studies of the oil extracted from pequi (Caryocar brasiliense, Camb.) pulp in rats.

The Caryocar brasiliense (pequi) is a Brazilian fruit of important geographic distribution and of broad popular use for nutritional purposes. This study aimed to evaluate the toxicological potential of pequi through the acute and subchronic toxicity tests. For the acute toxicity test, female Wistar rats received, orally, a single dose of 2000 mg/kg/bw of pequi oil and were observed for 14 days. In subchronic toxicity test, Wistar male and female rats received, orally, repeated doses of 125, 250, 500 or 1000 mg/kg/bw of the oil, being treated and observed for 28 days. In the acute toxicity test, no changes as well as no mortality were observed, indicating that the LD50 is higher than 2000 mg/kg/bw. In the subchronic toxicity test, the tested doses produced no significant changes in behavioral, physiological, biochemical or histopathologic parameters in animals. Some hematological abnormalities were found after subchronic exposure and need to be clarified. These results demonstrate the low toxicity of acute and subchronic to the oil of pequi in rats. However, additional studies are required in order to verify if the hematological abnormalities have any relation to the oil exposure and also provide sufficient safety evidence for the use of the oil in humans.

Antihyperalgesic and antidepressive actions of (R)-(+)-limonene, α-phellandrene, and essential oil from Schinus terebinthifolius fruits in a neuropathic pain model.

OBJECTIVES: Previous studies have shown that essential oil containing (R)-(+)-limonene and α-phellandrene, extracted from fruits of Schinus terebinthifolius Raddi, exhibit anti-inflammatory activity. This work aimed to verify the antihyperalgesic and antidepressive actions of (R)-(+)-limonene, α-phellandrene, and essential oil from S. terebinthifolius fruits in spared nerve injury (SNI) model of neuropathic pain in rats. METHODS: In the present work, essential oil from fruits of S. terebinthifolius, as well as the pure (R)-(+)-limonene and α-phellandrene compounds, were assayed for their effects on SNI-induced mechanical and cold hyperalgesia, and depressive-like behavior (immobility in forced swim test) in rats. The locomotor activity was evaluated in open-field test. RESULTS: Oral administration for up to 15 days of essential oil of S. terebinthifolius (100 mg/kg), (R)-(+)-limonene (10 mg/kg), α-phellandrene (10 mg/kg), and also subcutaneous 10 mg/kg dose of ketamine (positive control) significantly inhibited SNI-induced mechanical hyperalgesia and increased immobility in the forced swim test. On the 15th day of oral treatment, α-phellandrene, but neither the essential oil from S. terebinthifolius nor (R)-(+)-limonene, prevented the SNI-induced increase in sensitivity to a cold stimulus. The oral treatment with essential oil (100 mg/kg) or with compounds (10 mg/kg) did not interfere on locomotor activity. DISCUSSION: Together, the results of the present work show that essential oil of S. terebinthifolius and compounds present in this oil, including (R)-(+)-limonene and α-phellandrene, exhibit antihyperalgesic effects against mechanical hyperalgesia, and are antidepressive, while only α-phellandrene inhibited cold hyperalgesia in SNI rats.