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1.
Parasitology ; 144(4): 426-435, 2017 04.
Article de Anglais | MEDLINE | ID: mdl-27748211

RÉSUMÉ

There is an increasing interest in improving neurocysticercosis (NCC) diagnosis through the search of new and alternative antigenic sources, as those obtained from heterologous antigens. The aim of this study was to obtain potential biomarkers for NCC diagnosis after gel filtration chromatography [gel filtration fraction (GFF)] from the total saline extract (SE) from Taenia saginata metacestodes, followed by protein identification and application in immunodiagnostic. SE and GFF proteic profiles were characterized in gel electrophoresis, and diagnostic performance was verified by testing 160 serum samples through enzyme-linked immunosorbent assay and immunoblotting. Sensitivity (Se), specificity (Sp) and other diagnostic parameters were calculated. Polypeptides of interest in the diagnosis of human NCC present at GFF were analysed by mass spectrometry (MS) and B-cell epitopes were predicted. GFF had the best diagnostic parameters: Se 93·3%; Sp 93%; AUC 0·990; LR+ = 13·42 and LR- = 0·07, and proved to be useful reacting with serum samples in immunoblotting. Proteic profile ranged from 64 to 68 kDa and enolase and calcium binding protein calreticulin precursor were identified after MS. The enolase and calcium-binding protein calreticulin precursor showed 18 and 10 predicted B-cell epitopes, respectively. In conclusion we identified important markers in the GFF with high efficiency to diagnose NCC.


Sujet(s)
Chromatographie sur gel/méthodes , Protéines d'helminthes/métabolisme , Neurocysticercose/sang , Neurocysticercose/diagnostic , Taenia saginata/métabolisme , Animaux , Marqueurs biologiques/sang , Fractionnement chimique , Test ELISA , Déterminants antigéniques des lymphocytes B , Protéines d'helminthes/sang , Protéines d'helminthes/génétique , Humains , Dépistage de masse , Modèles moléculaires , Neurocysticercose/parasitologie , Conformation des protéines , Taenia saginata/isolement et purification
2.
Genet Mol Res ; 13(3): 7852-63, 2014 Sep 26.
Article de Anglais | MEDLINE | ID: mdl-25299099

RÉSUMÉ

Brown rust (causal agent Puccinia melanocephala) is an important sugarcane disease that is responsible for large losses in yield worldwide. Despite its importance, little is known regarding the genetic diversity of this pathogen in the main Brazilian sugarcane cultivation areas. In this study, we characterized the genetic diversity of 34 P. melanocephala isolates from 4 Brazilian states using loci identified from an enriched simple sequence repeat (SSR) library. The aggressiveness of 3 isolates from major sugarcane cultivation areas was evaluated by inoculating an intermediately resistant and a susceptible cultivar. From the enriched library, 16 SSR-specific primers were developed, which produced scorable alleles. Of these, 4 loci were polymorphic and 12 were monomorphic for all isolates evaluated. The molecular characterization of the 34 isolates of P. melanocephala conducted using 16 SSR loci revealed the existence of low genetic variability among the isolates. The average estimated genetic distance was 0.12. Phenetic analysis based on Nei's genetic distance clustered the isolates into 2 major groups. Groups I and II included 18 and 14 isolates, respectively, and both groups contained isolates from all 4 geographic regions studied. Two isolates did not cluster with these groups. It was not possible to obtain clusters according to location or state of origin. Analysis of disease severity data revealed that the isolates did not show significant differences in aggressiveness between regions.


Sujet(s)
Basidiomycota/génétique , Variation génétique , Répétitions microsatellites , Séquence nucléotidique , Basidiomycota/classification , Brésil , Amorces ADN , Marqueurs génétiques
3.
Parasitology ; 140(1): 69-75, 2013 Jan.
Article de Anglais | MEDLINE | ID: mdl-22931968

RÉSUMÉ

The aim of this study was to fractionate and partially characterize the antigenic extract of filariform larvae of Strongyloides venezuelensis in ion-exchange resin diethylaminoethyl sepharose (DEAE), to obtain antigenic fractions potentially applicable in immunoassays. Somatic antigen (SA) and its fractions DEAE S1 and DEAE S2 - which interacted with the resin - were evaluated by 1-dimensional electrophoresis to obtain protein profiles. SA and its fractions were tested in serum samples for IgG detection by ELISA. Serum samples (n = 155) were analysed: 50 from strongyloidiasis patients (G1), 55 from patients with other parasitic infections (G2) and 50 from healthy volunteers. Sensitivity (Se), specificity (Sp), area under curve (AUC) and likelihood ratios (LR) were calculated. The DEAE S2 fraction provided a high diagnostic value for IgG detection (Se 92·0%, Sp 91·4%, AUC 0·981, LR+ 10·75, LR - 0·09). In conclusion, the DEAE S2 fraction would probably be a source of immunodominant polypeptides for IgG detection in human strongyloidiasis serodiagnosis.


Sujet(s)
Antigènes d'helminthe , Chromatographie d'échange d'ions , Strongyloides/composition chimique , Strongyloïdose/diagnostic , Animaux , Test ELISA/normes , Humains , Immunoglobuline G/sang , Larve/composition chimique , Sensibilité et spécificité , Tests sérologiques , Sérum/parasitologie
4.
Parasitology ; 139(7): 956-61, 2012 Jun.
Article de Anglais | MEDLINE | ID: mdl-22309625

RÉSUMÉ

The aim of this study was to use larval, parasitic female and egg antigens from Strongyloides venezuelensis to detect parasite-specific IgG and immune complexes in human serum samples by enzyme-linked immunosorbent assay (ELISA). In total, 95 serum samples were analysed, consisting of 30 patients harbouring S. stercoralis larvae, 30 healthy subjects and 35 patients with other parasites. Sensitivity, specificity and diagnostic efficiency were calculated. A significant statistical difference was found in the detection of immune complexes and antibodies in patients harbouring S. stercoralis larvae from larval and eggs antigens, with higher positivity using larval antigen. The larval antigen showed the highest values for sensitivity, specificity and diagnostic efficiency in ELISA from detection of immune complexes. For the first time we used IgG anti-larvae, IgG anti-parasitic females or IgG anti-eggs for immune complex detection. We concluded that the association of antibody and immune complex detection could be used in the diagnosis of human strongyloidiasis.


Sujet(s)
Complexe antigène-anticorps/sang , Antigènes d'helminthe , Immunoglobuline G/sang , Strongyloides/immunologie , Strongyloïdose/diagnostic , Animaux , Spécificité des anticorps , Antigènes d'helminthe/immunologie , Femelle , Humains , Tests immunologiques , Larve/immunologie , Ovule/immunologie , Rats , Rat Wistar , Sensibilité et spécificité , Strongyloides/classification , Strongyloïdose/immunologie , Strongyloïdose/parasitologie
5.
Pharm Biol ; 50(1): 113-9, 2012 Jan.
Article de Anglais | MEDLINE | ID: mdl-22196586

RÉSUMÉ

CONTEXT: Essential oils (EOs) have been reported to possess pharmacological properties, of which those related to the central nervous system have been especially attributed to mono- and sesquiterpenes. Baccharis uncinella DC. (Asteraceae) is used by the Laklaño Indians (Santa Catarina, Brazil) for sedative purposes. Interestingly, the species does not seem to be used medicinally elsewhere in Brazil. OBJECTIVE: This study was designed to compare the composition and sedative properties of B. uncinella EOs obtained closer (BU-SC) and farther (BU-PR) to the Laklaño Indian Reserve. MATERIALS AND METHODS: BU-SC and BU-PR obtained by hydrodistillation were analyzed by CG-MS. Mice treated with BU-SC and BU-PR (50 and 100 mg/kg) were evaluated regarding pentobarbital-induced sleeping time, body temperature, and locomotion. RESULTS: BU-SC presents a higher monoterpene/sesquitherpene ratio (0.31); α-pinene (6.42%), limonene (7.21%), caryophyllene (26.13%), spathulenol (13.39%) and caryophyllene oxide (13.26%) were identified as major components. BU-PR presents a low monoterpene/sesquitepene ratio (0.004); spathulenol (32.93%), caryophyllene oxide (27.78%), viridiflorol (5.29%) and α-cadinol (2.42%) were identified as the main components. Both samples significantly (p < 0.05, ANOVA) decreased locomotion and body temperature, as well as increased sleeping time. The hypnotic activity was sensitive to the differences in monoterpene composition. CONCLUSIONS: In comparison with a sample collected in Paraná State, B. uncinella EO collected closer to the Laklaño Indians possess a composition that better justifies the claimed sedative properties. The study confirms the value of traditional information to guide bioactivity assessment in medicinal plants, and gives notice to the ecological factors that can interfere with the conclusions of such assessments.


Sujet(s)
Baccharis/composition chimique , Hypnotiques et sédatifs/pharmacologie , Huile essentielle/pharmacologie , Sommeil/effets des médicaments et des substances chimiques , Animaux , Température du corps/effets des médicaments et des substances chimiques , Brésil , Relation dose-effet des médicaments , Chromatographie gazeuse-spectrométrie de masse , Hypnotiques et sédatifs/administration et posologie , Hypnotiques et sédatifs/isolement et purification , Locomotion/effets des médicaments et des substances chimiques , Mâle , Souris , Monoterpènes/isolement et purification , Monoterpènes/pharmacologie , Huile essentielle/administration et posologie , Huile essentielle/isolement et purification , Facteurs temps
6.
Phytomedicine ; 18(4): 327-33, 2011 Feb 15.
Article de Anglais | MEDLINE | ID: mdl-20739160

RÉSUMÉ

UNLABELLED: Alzheimer's disease (AD) is expected to affect more than 22 million people worldwide by 2025, causing devastating suffering and enormous costs to families and society. AD is a multifactorial disease, with a complex pathological mosaic. In rodents, AD-like dementia can be induced by cerebral microinjection of Aß peptide, leading to amyloid deposits, amnesia and various features of neurodegeneration. Marapuama (Ptychopetalum olacoides) is regarded as a "brain tonic" in the Amazon region and shows a nootropic profile in rodents. AIM OF THE STUDY: Because a specific extract (POEE) of Marapuama was shown to possess promnesic and anti-amnesic properties, the aim of this study was to verify if POEE is also effective against Aß(1-42)-induced cognitive deficit in mice. Additionally, Aß deposits (Congo red), GFAP immunoreactivity (immunohistochemistry), and neurodegenerative changes in the hippocampal pyramidal layer (Nissl) were examined as measures of Aß(1-42)-induced neurodegeneration. MATERIALS AND METHODS: CF1 mice were subjected to the experimental Alzheimer model with the Aß(1-42) i.c.v. administration. The effects of POEE 800 mg/kg were evaluated over 14 consecutive days of treatment. RESULTS: The data show that 14 days of oral treatment with POEE (800 mg/kg) was effective in preventing Aß-induced cognitive impairment, without altering the levels of BDNF and with parallel reductions in Aß deposits and astrogliosis. CA1 hippocampus loss induced by Aß(1-42) was also diminished in POEE-treated mice. CONCLUSION: This study offers evidence of functional and neuroprotective effects of two weeks treatment with a Ptychopetalum olacoides extract against Aß peptide-induced neurotoxicity in mice. Given the multifactorial nature of neurodegeneration, the considerable potential for an AChE inhibitor displaying associated neuroprotective properties such as here reported warrants further clinic evaluation.


Sujet(s)
Troubles de la cognition/traitement médicamenteux , Dégénérescence nerveuse/traitement médicamenteux , Nootropiques/pharmacologie , Olacaceae/composition chimique , Phytothérapie , Extraits de plantes/pharmacologie , Maladie d'Alzheimer/traitement médicamenteux , Peptides bêta-amyloïdes/pharmacologie , Animaux , Encéphale/effets des médicaments et des substances chimiques , Démence/traitement médicamenteux , Modèles animaux de maladie humaine , Évolution de la maladie , Mâle , Souris , Névroglie/anatomopathologie , Nootropiques/usage thérapeutique , Fragments peptidiques/pharmacologie , Extraits de plantes/usage thérapeutique , Plantes médicinales/composition chimique
7.
Phytomedicine ; 17(12): 956-62, 2010 Oct.
Article de Anglais | MEDLINE | ID: mdl-20833520

RÉSUMÉ

The goal of acetylcholinesterase inhibitors (AChEIs) used to treat Alzheimer's patients is an improvement in cholinergic transmission. While currently available AChEIs have limited success, a huge impediment to the development of newer ones is access to the relevant brain areas. Promnesic, anti-amnesic and AChEI properties were identified in a standardized ethanol extract from Ptychopetalum olacoides (POEE), a medicinal plant favored by the elderly in Amazon communities. The purpose of this study was to provide conclusive evidence that orally given POEE induces AChE inhibition in brain areas relevant to cognition. Histochemistry experiments confirmed that the anticholinesterase compound(s) present in POEE are orally bioavailable, inducing meaningful AChE inhibition in the hippocampus CA1 (∼33%) and CA3 (∼20%), and striatum (∼17%). Ellman's colorimetric analysis revealed that G1 and G4 AChE isoforms activities were markedly inhibited (66 and 72%, respectively) in hippocampus and frontal cortex (50 and 63%, respectively), while G4 appeared to be selectively inhibited (72%) in the striatum. Western blotting showed that POEE did not induce significant changes in the AChE immunocontent suggesting that its synthesis is not extensively modified. This study provides definitive proof of meaningful anticholinesterase activity compatible with the observed promnesic and anti-amnesic effects of POEE in mice, reaffirming the potential of this extract for treating neurodegenerative conditions where a hypofunctioning cholinergic neurotransmission is prominent. Adequate assessment of the safety and efficacy of this extract and/or its isolated active compound(s) are warranted.


Sujet(s)
Acetylcholinesterase/métabolisme , Encéphale/effets des médicaments et des substances chimiques , Anticholinestérasiques/pharmacologie , Nootropiques/pharmacologie , Olacaceae , Phytothérapie , Extraits de plantes/pharmacologie , Animaux , Cognition/effets des médicaments et des substances chimiques , Mâle , Souris , Lignées consanguines de souris , Maladies neurodégénératives/traitement médicamenteux , Racines de plante , Isoformes de protéines
8.
Phytomedicine ; 17(3-4): 248-53, 2010 Mar.
Article de Anglais | MEDLINE | ID: mdl-19682881

RÉSUMÉ

With the recognition that high levels of sustained stress are associated with the natural course of countless illnesses, effective anti-stress agents have gained importance. Improved endurance to particularly stressful periods is one of the medicinal claims for Marapuama (Ptychopetalum olacoides Bentham, PO), a popular Amazonian herbal. The purpose of this study was to evaluate if PO possesses anti-stress properties. To this end, an extract from PO (POEE) was evaluated on anxiety and glucose levels in mice submitted to the unpredictable chronic mild stress (UCMS) paradigm. POEE did not present anxiolytic effects, but was able to prevent (p<0.01) the UCMS-induced anxiety as assessed by the light/dark test (time spent in the lit area, POEE 100 and 300mg/kg 235.9+/-20.6s and 250.4+/-17.4s, respectively, compared to DMSO 104.7+/-24.4s). Likewise, although POEE did not induce noticeable effects on glycemia, it effectively (p<0.01) prevented the UCMS-induced hyperglycemia (POEE 100 and 300mg/kg 106.4+/-6.7mg/dl and 107.3+/-3.3mg/dl, respectively, compared to DMSO 134.6+/-5.9mg/dl). Additionally, POEE (50-200mg/kg i.p. and 800mg/kg p.o.) significantly (p<0.01 and p<0.05, respectively) increased the time to hypoxia-induced convulsion (by 38%, 51%, 59% and 27%, respectively for i.p. and p.o. treatments). The data indicate that POEE counteracts some of the effects brought about by chronic stress. This study combined with the identified antioxidant and neuroprotective properties, as well as the claimed benefits associated with stressful periods suggest that Ptychopetalum olacoides (Marapuama) might possess adaptogen-like properties.


Sujet(s)
Anxiolytiques/usage thérapeutique , Anxiété/prévention et contrôle , Hyperglycémie/prévention et contrôle , Olacaceae , Extraits de plantes/usage thérapeutique , Crises épileptiques/traitement médicamenteux , Animaux , Anxiolytiques/pharmacologie , Antioxydants/pharmacologie , Antioxydants/usage thérapeutique , Glycémie/effets des médicaments et des substances chimiques , Diméthylsulfoxyde/pharmacologie , Diméthylsulfoxyde/usage thérapeutique , Hyperglycémie/étiologie , Hypoxie/traitement médicamenteux , Lumière , Mâle , Souris , Lignées consanguines de souris , Neuroprotecteurs/pharmacologie , Neuroprotecteurs/usage thérapeutique , Olacaceae/composition chimique , Phytothérapie , Extraits de plantes/pharmacologie , Racines de plante , Stress psychologique/prévention et contrôle
9.
Phytomedicine ; 14(11): 763-9, 2007 Nov.
Article de Anglais | MEDLINE | ID: mdl-17433649

RÉSUMÉ

Ptychopetalum olacoides (PO) roots are used by Amazonian peoples to prepare traditional remedies for treating various central nervous system conditions in which free radicals are likely to be implicated. Following the identification of PO ethanol extract (POEE) free-radical scavenging properties in vitro, the aim of this study was to verify the in vivo antioxidant effect of POEE. Aging mice (14 months) were treated (i.p.) with saline, DMSO (20%) or POEE (100mg/kg body wt.), and the hippocampi, cerebral cortex, striata, hypothalamus and cerebellum dissected out 60 min later to measure antioxidant enzyme activities, free-radical production and damage to macromolecules. POEE administration reduced free-radical production in the hypothalamus, lead to significant decrease in lipid peroxidation in the cerebral cortex, striatum and hypothalamus, as well as in the carbonyl content in cerebellum and striatum. In terms of antioxidant enzymes, catalase activity was increased in the cortex, striatum, cerebellum and hippocampus, while glutathione peroxidase activity was increased in the hippocampus. This study suggests that POEE contains compounds able to improve the cellular antioxidant network efficacy in the brain, ultimately reducing the damage caused by oxidative stress.


Sujet(s)
Encéphale/effets des médicaments et des substances chimiques , Neuroprotecteurs/pharmacologie , Olacaceae , Phytothérapie , Extraits de plantes/pharmacologie , Animaux , Antioxydants/administration et posologie , Antioxydants/pharmacologie , Antioxydants/usage thérapeutique , Encéphale/enzymologie , Brésil , Piégeurs de radicaux libres/administration et posologie , Piégeurs de radicaux libres/pharmacologie , Piégeurs de radicaux libres/usage thérapeutique , Peroxydation lipidique/effets des médicaments et des substances chimiques , Mâle , Médecine traditionnelle , Souris , Neuroprotecteurs/administration et posologie , Neuroprotecteurs/usage thérapeutique , Extraits de plantes/administration et posologie , Extraits de plantes/usage thérapeutique , Racines de plante
10.
Phytomedicine ; 9(6): 523-9, 2002 Sep.
Article de Anglais | MEDLINE | ID: mdl-12403161

RÉSUMÉ

The bark of Croton cajucara Benth. (Euphorbiaceae) is used widely in Amazonian folk medicine for the treatment of a wide range of gastrointestinal symptoms. Infusions of C. cajucara bark contain dehydrocrotonin (DHC), the furan diterpene, and an essential oil, a rich mixture of sesquiterpenes. Although the antiulcerogenic activity of the essential oil has been studied in different gastric ulcer models in mice and rats, its mechanism remains unclear. In this work, we examined the ability of this essential oil to increase PGE2 release from mucus cells, as well as its effects on the amount of gastric mucus and on the healing of acetic acid-induced gastric ulcers. The essential oil (100 mg/kg body wt., p.o), significantly increased PGE2 production by glandular cells (by 102% as compared to control) and the amount of Alcian blue binding to the gastric mucus. In chronic gastric ulcers, a single daily oral dose of essential oil (100 mg/kg body wt.) for 14 consecutive days accelerated ulcer healing to an extent similar to that seen with an equal dose of cimetidine. Thus, the protective and healing actions of the essential oil from C. cajucara bark on gastric lesions resulted mainly from an increase in PGE2 release and gastric mucus formation which would protect the gastric mucosa.


Sujet(s)
Croton , Diterpènes de type clérodane , Muqueuse gastrique/effets des médicaments et des substances chimiques , Huile essentielle/pharmacologie , Ulcère gastrique/traitement médicamenteux , Cicatrisation de plaie/effets des médicaments et des substances chimiques , Animaux , Antiulcéreux/pharmacologie , Antiulcéreux/usage thérapeutique , Cimétidine/pharmacologie , Cimétidine/usage thérapeutique , Dinoprostone/biosynthèse , Diterpènes/pharmacologie , Diterpènes/usage thérapeutique , Muqueuse gastrique/métabolisme , Muqueuse gastrique/anatomopathologie , Mâle , Souris , Huile essentielle/usage thérapeutique , Phytothérapie , Écorce/composition chimique , Extraits de plantes/pharmacologie , Extraits de plantes/usage thérapeutique , Rats , Rat Wistar
11.
Phytother Res ; 16(3): 223-6, 2002 May.
Article de Anglais | MEDLINE | ID: mdl-12164265

RÉSUMÉ

Alcohol infusions of roots of Ptychopetalum olacoides Benth. (PO), known as Marapuama or Muirapuama, are used in the Brazilian Amazon as a 'nerve tonic'. Over the years PO has been found increasingly in phytoformulations and regarded as a stimulant, claimed to enhance physical and mental performances. This study determined that a P. olacoides ethanol extract (30, 100 and 300 mg/kg) decreased exploratory behaviour in the hole-board test, without interfering with locomotion or motor coordination (rota-rod test). The data are comparable to that obtained with pentylenetetrazol (40 mg/kg), suggesting an anxiogenic effect of P. olacoides.


Sujet(s)
Anxiolytiques/pharmacologie , Olacaceae , Extraits de plantes/pharmacologie , Animaux , Comportement animal/effets des médicaments et des substances chimiques , Brésil , Locomotion/effets des médicaments et des substances chimiques , Mâle , Souris , Lignées consanguines de souris , Aptitudes motrices/effets des médicaments et des substances chimiques , Pentétrazol/pharmacologie , Racines de plante/composition chimique
12.
Phytomedicine ; 8(3): 202-6, 2001 May.
Article de Anglais | MEDLINE | ID: mdl-11417913

RÉSUMÉ

We have previously reported that the alkaloid extract of Psychotria colorata (Willd. ex R. & S.) Muell. Arg., had marked dose-dependent, opioid-like activity. Phytochemical analyses of P. colorata flowers and leaves identified several pyrrolidinoindoline alkaloids, including psychotridine. To further investigate the activity and mechanism of action of Psychotria alkaloids, we studied the effects of psychotridine on thermal and chemical models of analgesia. In the tail-flick model, psychotridine presents a dose-dependent analgesic effect; the effect is not reversed by prior treatment with naloxone. Psychotridine dose-dependently decreased capsaicin-induced pain. Performance in the rotarod test showed that psychotridine does not induce motor deficits at doses effective in analgesia models. Psychotridine inhibited [3H]MK-801 (dizocilpine) binding to cortex membranes in a dose-dependent manner. Binding is completely abolished at 300 nM. The data rule out opioid activity, and the inhibition of capsaicin-induced pain and of radioligand binding strongly suggest the participation of NMDA receptors in psychotridine-induced analgesia.


Sujet(s)
Alcaloïdes/pharmacologie , Analgésiques/pharmacologie , Indoles/pharmacologie , Récepteurs du N-méthyl-D-aspartate/métabolisme , Rubiaceae/composition chimique , Analgésiques/composition chimique , Analgésiques morphiniques/pharmacologie , Animaux , Maléate de dizocilpine/pharmacologie , Relation dose-effet des médicaments , Indoles/composition chimique , Mâle , Souris , Structure moléculaire , Morphine/pharmacologie , Neuroprotecteurs/pharmacologie , Extraits de plantes/pharmacologie , Extraits de plantes/usage thérapeutique , Structures de plante
13.
J Ethnopharmacol ; 69(3): 229-34, 2000 Mar.
Article de Anglais | MEDLINE | ID: mdl-10722204

RÉSUMÉ

The gastroprotective activity of the essential oil from the bark of Croton cajucara Benth (Euphorbiaceae) was assessed in three different models of experimentally induced gastric ulcer in mice. At oral dose of 100 mg/kg the essential oil reduced gastric lesions induced by hypothermic restraint stress and HCl/ethanol significantly. In the HCl/ethanol model a dose-dependent gastroprotective effect was found. Moreover, significant changes in gastric parameters such as pH, secretion rate and total gastric acid were found after intraduodenal administration of essential oil under ligated pylorus (Shay) conditions. The acute toxicity of essential oil was assessed in mice. The LD50 values were 9.3 and 680 mg/kg for oral and intraperitoneal administrations, respectively. The cytotoxicity of essential oil was studied also. A dose-dependent cell viability inhibition was found in V79 fibroblast cell cultures with an IC50 of 22.9 microg/ml. Our results support the pharmacological study of this essential oil.


Sujet(s)
Euphorbiaceae/composition chimique , Huile essentielle/pharmacologie , Ulcère gastrique/traitement médicamenteux , Estomac/effets des médicaments et des substances chimiques , Animaux , Lignée cellulaire , Survie cellulaire/effets des médicaments et des substances chimiques , Cricetinae , Dose létale 50 , Souris , Huile essentielle/usage thérapeutique
14.
Planta Med ; 66(8): 770-2, 2000 Dec.
Article de Anglais | MEDLINE | ID: mdl-11199142

RÉSUMÉ

To further understand the mechanism of analgesic activity and structural requirements of pyrrolidinoindoline alkaloids identified in Psychotria colorata, we here report the analgesic activity of the trimer hodgkinsine on thermal and chemical models of analgesia. Results show that hodgkinsine produces a dose-dependent naloxone reversible analgesic effect in thermal models of nociception, suggesting that activation of opioid receptors participates in hodgkinsine's mode of action. Hodgkinsine shows a potent dose-dependent analgesic activity against capsaicin-induced pain, indicating the participation of NMDA receptors in hodgkinsine-induced analgesia. Such a dual mechanism of action may be of interest for developing innovative analgesics.


Sujet(s)
Analgésiques non narcotiques/pharmacologie , Indoles/pharmacologie , Rubiaceae/composition chimique , Analgésiques non narcotiques/composition chimique , Analgésiques non narcotiques/isolement et purification , Animaux , Indoles/composition chimique , Indoles/isolement et purification , Mâle , Souris , Structure moléculaire
15.
An Acad Bras Cienc ; 71(2): 189-201, 1999.
Article de Anglais | MEDLINE | ID: mdl-10412490

RÉSUMÉ

Although recently developed drugs have brought significant improvement, the treatment of psychotic disorders still presents serious drawbacks. Since inherent complexity and lack of satisfactory understanding of the underlying pathophysiology impose limits for rational drug design, resourceful approaches in the search for antipsychotics are pertinent. This paper reports pharmacological properties of alstonine, a heteroyohimbine type alkaloid, which exhibited an antipsychotic-like profile, inhibiting amphetamine-induced lethality, apomorphine-induced stereotypy and potentiating barbiturate-induced sleeping time. Atypical features of alstonine were the prevention of haloperidol-induced catalepsy and lack of direct interaction with D1, D2 and 5-HT2A receptors, classically linked to antipsychotic mechanism of action.


Sujet(s)
Neuroleptiques/pharmacologie , Plantes médicinales , Alcaloïdes formés par condensation de sécologanine et de tryptamine/pharmacologie , Animaux , Mâle , Souris , Nigeria , Sommeil/effets des médicaments et des substances chimiques
16.
An. acad. bras. ciênc ; 71(2): 189-201, jun. 1999. ilus, graf
Article de Anglais | LILACS | ID: lil-234513

RÉSUMÉ

Although recently developed drugs have brought significant improvement, the treatment of psychotic disorders still presents serious drawbacks. Since inherent complexity and lack of satisfactory understanding of the underlying pathophysiology impose limits for rational drug design, resourceful approaches in the search for antipsychotics are pertinent. This paper reports pharmacological properties of alstonine, a heteroyohimbine type alkaloid, Which exbitited an antipsychotic-like profile, inhibiting amphetamine-induced lethaly, apomorphine-induced steotypy and potentiating barbiturate-induced slleping time. Atypical features of alstonine were the prevention of haloperidol-induced catalepsy and lack of direct interaction with D1, D2 and 5-HT2A receptors, classically linked to antipsychotic mechanism of action.


Sujet(s)
Animaux , Mâle , Souris , Neuroleptiques/pharmacologie , Plantes médicinales , Alcaloïdes formés par condensation de sécologanine et de tryptamine/pharmacologie , Amfétamine/antagonistes et inhibiteurs , Apomorphine/antagonistes et inhibiteurs , Barbituriques/antagonistes et inhibiteurs , Stimulants du système nerveux central/antagonistes et inhibiteurs , Chlorpromazine/pharmacologie , Clozapine/pharmacologie , Diazépam/pharmacologie , Émétiques/antagonistes et inhibiteurs , Halopéridol/pharmacologie , Hypnotiques et sédatifs/antagonistes et inhibiteurs , Nigeria , Pentobarbital/pharmacologie , Réserpine/pharmacologie , Sommeil/effets des médicaments et des substances chimiques , Stéréotypes , Sulpiride/pharmacologie
17.
J Pharm Pharmacol ; 51(3): 341-6, 1999 Mar.
Article de Anglais | MEDLINE | ID: mdl-10344636

RÉSUMÉ

Croton cajucara Benth. (Euphorbiaceae) is widely used in Amazonian folk medicine for the treatment of a wide range of gastrointestinal symptoms. The essential oil from its bark was investigated for acute toxicity in mice and for its ability to prevent the formation of ulceration of the gastric mucosa in different models of experimentally induced gastric ulcer in mice and rats. When previously administered orally at a dose of 100 mg kg(-1), the essential oil significantly reduced (P < 0.01) the gastric injury induced by hypothermic restraint stress (48%), indomethacin (47%), ethanol (86%) and pylorus ligature models (87%) in rats. In the HCl/ethanol-induced gastric ulcer model in mice, at oral doses of 100 and 200 mg kg(-1), the essential oil from C. cajucara significantly reduced (P < 0.01) the formation of gastric lesions by 52% and 67%, respectively, when compared with the control group. In rats submitted to pylorus ligature, the essential oil given orally increased the volume of gastric juice when compared with the control group (P < 0.01). When the essential oil (100 mg kg(-1)) was administered intraduodenally to mice, significant modifications were found in gastric parameters such as pH and total acid content after oil treatment. We observed significant changes (P < 0.01) in gastric juice parameters such as an increase in volume and a decrease in gastric acidity (pH and total acid content). The acute toxicologic effects of the essential oil from C. cajucara were assessed in mice. The LD50 values were 9.3 g kg(-1) by the oral route and 680 mg kg(-1) by the intraperitoneal route. The good yield of essential oil obtained from dried C. cajucara bark (1%) as well as its anti-ulcerogenic activity and low toxicity suggest that pharmacological studies of this substance as a potential new anti-ulcerogenic drug are warranted.


Sujet(s)
Euphorbiaceae/composition chimique , Huile essentielle/pharmacologie , Extraits de plantes/pharmacologie , Ulcère gastrique/prévention et contrôle , Animaux , Euphorbiaceae/toxicité , Mesure de l'acidité gastrique , Mâle , Médecine traditionnelle , Souris , Huile essentielle/toxicité , Phytothérapie , Extraits de plantes/toxicité , Rats , Rat Wistar , Ulcère gastrique/étiologie , Stress physiologique/complications
18.
J Chromatogr B Biomed Sci Appl ; 716(1-2): 147-52, 1998 Sep 25.
Article de Anglais | MEDLINE | ID: mdl-9824227

RÉSUMÉ

The effectiveness of solid-phase extraction with Florisil for the determination of 12 organochlorine pesticide residues from human serum was examined. Recoveries greater than 84% and coefficients of variation better than 19% were obtained. Others methods, such as column partition and matrix solid-phase dispersion, were compared. The better method provides quantification limits ranging from 1.08 microg/l for gamma-HCH and 37.5 microg/l for p,p'-DDT when capillary gas-liquid chromatography with electron-capture detection is used for the final determination.


Sujet(s)
Chromatographie en phase gazeuse/méthodes , Insecticides/sang , Résidus de pesticides/sang , Acétone , Hexanes , Humains , Indicateurs et réactifs , Silicates de magnésium , Dichloro-méthane , Sensibilité et spécificité
19.
Pharmacol Biochem Behav ; 60(1): 133-41, 1998 May.
Article de Anglais | MEDLINE | ID: mdl-9610935

RÉSUMÉ

Although recently developed drugs have brought significant improvement, the treatment of psychotic disorders still presents serious drawbacks. Because inherent complexity and lack of satisfactory understanding of the underlying pathophysiology impose limits for rational drug design, resourceful approaches in the search for antipsychotics are pertinent. This article reports pharmacological properties of alstonine, a heteroyohimbine-type alkaloid, which exhibited an antipsychotic-like profile, inhibiting amphetamine-induced lethality, apomorphine-induced stereotypy, and potentiating barbiturate-induced sleeping time. Atypical features of alstonine were the prevention of haloperidol-induced catalepsy and lack of direct interaction with D1, D2 and 5-HT2A receptors, classically linked to antipsychotic mechanism of action.


Sujet(s)
Neuroleptiques/pharmacologie , Comportement animal/effets des médicaments et des substances chimiques , Alcaloïdes formés par condensation de sécologanine et de tryptamine/pharmacologie , Amfétamine/antagonistes et inhibiteurs , Amfétamine/toxicité , Animaux , Apomorphine/antagonistes et inhibiteurs , Catalepsie/induit chimiquement , Catalepsie/prévention et contrôle , Évaluation préclinique de médicament , Halopéridol/antagonistes et inhibiteurs , Halopéridol/pharmacologie , Mâle , Souris , Rats , Rat Wistar , Récepteur dopamine D1/effets des médicaments et des substances chimiques , Récepteur D2 de la dopamine/effets des médicaments et des substances chimiques , Récepteurs sérotoninergiques/effets des médicaments et des substances chimiques , Sommeil/effets des médicaments et des substances chimiques , Comportement stéréotypé/effets des médicaments et des substances chimiques
20.
Planta Med ; 64(2): 126-9, 1998 Mar.
Article de Anglais | MEDLINE | ID: mdl-9525103

RÉSUMÉ

trans-Dehydrocrotonin (DHC), the major diterpene isolated from Croton cajucara Benth, was assayed for antiulcerogenic activity in four induced gastric ulcer models in the rat. At an oral dose of 100 mg/kg DHC showed a significant antiulcerogenic effect on ulcers induced by hypothermic restraint stress, ethanol, and pylorus ligature. No significant changes in indomethacin-induced gastric lesions or modifications in gastric parameters such as wall mucus, secretion rate, pH, and total acid content were found after DHC treatment. The acute toxicological effects of DHC were assessed in mice. The LD50 values were 876 mg/kg and 47.2 mg/kg for oral and intraperitoneal administrations, respectively. The cytotoxicity of DHC was also studied. A dose-dependent inhibition of cell viability was observed in V-79 fibroblast cell cultures with an IC50 of 240 microM. The high yields of DHC obtained from dried C. cajucara barks as well as its good antiulcerogenic activity and low toxicity support the pharmacological study of this compound as a potential new antiulcerogenic drug.


Sujet(s)
Antiulcéreux/usage thérapeutique , Diterpènes de type clérodane , Diterpènes/usage thérapeutique , Plantes médicinales , Ulcère gastrique/prévention et contrôle , Animaux , Antiulcéreux/isolement et purification , Antiulcéreux/toxicité , Lignée cellulaire , Survie cellulaire/effets des médicaments et des substances chimiques , Cimétidine/usage thérapeutique , Diterpènes/isolement et purification , Diterpènes/toxicité , Éthanol , Indométacine , Muqueuse intestinale/effets des médicaments et des substances chimiques , Muqueuse intestinale/anatomopathologie , Dose létale 50 , Mâle , Souris , Rats , Rat Wistar , Contention physique , Ulcère gastrique/induit chimiquement , Ulcère gastrique/psychologie , Stress psychologique
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