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We have recently demonstrated that rodents treated intranasally with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) suffered impairments in olfactory, cognitive and motor functions associated with time-dependent disruption of dopaminergic neurotransmission in different brain structures conceivably analogous to those observed during different stages of Parkinson’s disease (PD). On the other hand, the proanthocyanidin-rich fraction (PRF) obtained from the bark of Croton celtidifolius Baill (Euphorbiaceae), a tree frequently found in the Atlantic forest in south Brazil, has been described to have several neurobiological activities including antioxidant and anti-inflammatory properties, which may be of interest in the treatment of PD. The present data indicated that the pretreatment with PRF (10 mg/kg, i.p.) during five consecutive days was able to prevent mitochondrial complex-I inhibition in the striatum and olfactory bulb, as well as a decrease of the enzyme tyrosine hydroxylase expression in the olfactory bulb and substantia nigra of rats infused with a single intranasal administration of MPTP (1 mg/nostril). Moreover, pretreatment with PRF was found to attenuate the short-term social memory deficits, depressive-like behavior and reduction of locomotor activity observed at different periods after intranasal MPTP administration in rats. Altogether, the present findings provide strong evidence that PRF from C. celtidifolius may represent a promising therapeutic tool in PD, thus being able to prevent both motor and non-motor early symptoms of PD, together with its neuroprotective potential.

Elephantopus scaber has been used in Brazil as a traditional remedy to cause diuresis, antipyresis and to eliminate bladder stones. In the current study, aqueous and hydroalcoholic extracts of whole plants were tested for acute toxicity, analgesic, antipyretic, antiinflammatory, cardiovascular, diuretic and constipating activities. Both extracts (0.3–6 g/kg i.p.) induced writhing, loss of muscle tone, ataxia, prostration and death in mice. No analgesic effects of these extracts were detected using mouse hot-plate and acetic acidinduced writhing tests. Both extracts failed to modify diuresis or carrageenan-induced rat paw edema. In contrast, given intraperitoneally, both reduced brewer's yeast-induced hyperthermia in rats, but when given orally did not affect it. Moreover, the aqueous extract decreased the intestinal transit time in mice while the hydroalcoholic extract increased it. Finally, these extracts, given intravenously, reduced blood pressure and heart rate in rats; these effects could be blocked by atropine but not by co-administration of pyrilamine and cimetidine.

Roots of Wilbrandia ebracteata Cogn., Cucurbitaceae, used in folk medicine for treatment of rheumatic disease, are rich in cucurbitacins. Dihydrocucurbitacin B is the most abundant cucurbitacin while cucurbitacin B is a minor component. A reverse-phase HPLC system was developed for simultaneous quantitative assay of these cucurbitacins in the roots. The optimised experimental conditions were acetonitrile/H(2)0 40:60, flow-rate 1.2 mL/min., detection at 230 nm and isocratic elution. A variety of sample preparation modes were tested and the extraction with dichloromethane under reflux gave better results. The validation process included linearity, accuracy, repeatability and intermediate precision. The calibration curve of dihydrocucurbitacin B was linear from 40.00 to 400 μg/mL, the recovery was 95.5±3.01%, the intermediate precision was found to be 1.64% and the repeatability varied between 1.30 to 2.05%. The calibration curve of cucurbitacin B was linear from 4.00 to 240 μg/mL, intermediate precision was found to be 2.29% and repeatability varied between 1.03 to 2.95%. Analysis of the same specimen of W. ebracteata every year from 2002 to 2005 revealed a great rise on the cucurbitacin B concentration after the root was attacked by an herbivore.

A identificação, extração, isolamento e caracterização de princípios ativos vegetais que modulam a viabilidade celular são de grande interesse clínico e farmacológico. Testes fitoquímicos têm demonstrado a presença de vários compostos oriundos dos metabolismos primário e secundário da Aloe vera L. A aloína é uma antraquinona isolada do parênquima clorofiliano da A. vera L que, sabe-se, apresenta atividade biológica. A atividade antitumoral da aloína e do extrato do parênquima clorofiliano foi avaliada, in vitro, com a utilização de células de melanoma de camundongo da linhagem B16-F10. Nessa análise, células incubadas em atmosfera com 5% de CO2 foram tratadas em diferentes concentrações de aloína e de extrato do parênquima, a 37ºC. A aloína e o extrato alteraram a estabilidade celular, exercendo efeito modulador sobre a viabilidade das células tumorais. Os dados experimentais foram representados por meio de um modelo matemático. Neste estudo, verificou-se que o extrato do parênquima clorofiliano é 2,3 vezes mais tóxico que a aloína.

Proanthocyanidins are condensed tannins present in fruits, vegetables, and flowers, consumed in the human diet. These compounds are believed to decrease coronary heart disease. The present study was designed to investigate the relaxing effects of a proanthocyanidin-rich fraction (PRF) obtained from Croton celtidifolius BAILL (Euphorbiaceae) barks in rat mesenteric arterial bed (MAB) and isolated mesenteric artery (MA). In the MAB pre-contracted with phenylephrine (Phe), PRF (0.1 –100 μ g) induced a concentration-dependent relaxation of 73% (compared to the control). This effect was significantly reduced by the nitric oxide (NO) synthase inhibitor Nω-nitro-L-arginine (L-NOARG) or high K+solution and completely abolished in vessels perfused with KCl plus L-NOARG. However, the vasorelaxant effect was not altered by indomethacin, atropine, yohimbine, pyrilamine, or K+-channel blockers: BaCl2, glibenclamide, ouabain, and 4-aminopyridine. In isolated MA pre-contracted with Phe, PRF also induced a concentration-dependent relaxation (0.1 –30 μ g/mL), which was in turn inhibited by endothelial removal, guanylyl cyclase inhibitor 1H [1,2,3]oxadiazolo[4,3-alpha]quinoxalin, charybdotoxin (ChTx), and ChTx plus apamin. Moreover, the relaxant effect was not altered by HOE140 and apamin given alone. The present study demonstrates that the vasorelaxing effect of PRF is dependent upon the NO–cGMP pathway in combination with hyperpolarization due to activation of Ca2+-dependent K+channels. Keywords:: Croton celtidifolius, proanthocyanidin, vasorelaxation, nitric oxide (NO), K+channel

Chemical analysis of Cordyline dracaenoides (Kunth) demonstrated the presence of steroidal saponins and anthocyanidins in the stem, rhizome and root. Small amounts of tannins were also detected in its stem and rhizome. Pharmacological analysis revealed different effects according to the part of the plant used. Crude aqueous/alcoholic extract (CE) from the rhizome inhibited carrageenan-induced rat paw oedema, while the CE obtained from the root significantly decreased the locomotor activity and potentiated barbiturate-induced hypnosis in mice. The CE from the roots inhibited noradrenaline-induced contraction in the rat vas deferens in a concentration-dependent and a noncompetitive manner, while the CE from the rhizome caused a parallel displacement to the left of noradrenaline concentration response curves. In the isolated rat stomach, the CE from the roots promoted a concentration-dependent displacement to the right of the serotonin concentration response curve allied to a marked inhibition of its maximal response, while the CE from the rhizome produced only an inhibition of about 40% of serotonin-contractile responses. These results suggest that the CE from C. dracaenoides exhibits a potent and long lasting antioedematogenic effect, has central depressant effects and potentiates noradrenaline-induced contractile responses of the isolated rat vas deferens. All these effects may be, at least in part, related to the presence of steroidal saponins in this plant.

Croton celtidifolius Bailon, commonly known as Sangue-de-Adave or Pau-Andrade, is a tree found in the Atlantic forest of southern Brazil. It has been popularly used for the treatment of inflammatory and ulcerative disorders. Phytochemical analysis demonstrated the presence of flavonoids and proanthocyanidins in an ethyl acetate fraction (EAF) from C. celtidifolius Bailon. In this study, we have evaluated the effects of EAF and its sub-fractions (35 and 63, catechin) on inflammatory (cell migration and plasma extravasation) and oxidative (lipid peroxidation, superoxide dismutase (SOD) activity and superoxide anion production) parameters in carrageenan-induced pleurisy in rats. NO production was also measured by nitrite/nitrate levels. EAF and sub-fraction 63 (63SF) showed anti-inflammatory activity, as indicated by a reduction in plasma extravasation and cell migration (mainly polymorphonuclear leukocytes) to the pleural cavity. Furthermore, EAF treatment decreased the production of superoxide radical anion by cells isolated from the pleural cavity, while it did not affect the nitrite/nitrate levels in exudates. The results show that C. celtidifolius contains substances with antioxidant and anti-inflammatory activity that, at least in part, act by a modulation of oxidative stress by phenolic compounds.

The chemical composition of the chromatography 63 subfraction (63SF) from the ethyl acetate soluble fraction of the crude extract of Croton celtidifolius bark presented a high content of total proanthocyanidins (75.0 ± 2.3%). HPLC analysis of 63SF revealed a dimeric profile (e.g. catechin-(4α → 8)-catechin and gallocatechin-(4α → 8)-catechin) and polymeric proanthocyanidins. In pharmacological investigations, 63SF administered intraperitoneally exhibited dose-dependent antinociceptive activity against several chemical stimuli, including the intraperitoneal injection of acetic acid (ID50 (the dose of 63SF which was able to reduce the nociceptive response by 50% relative to the control value) = 0.9 (0.5–1.6)) and the intraplantar injection of capsaicin (ID50 = 13.0 (10.0–17.0)), glutamate (ID50 = 4.0 (2.0–7.0)) and formalin (ID50 first phase = 36.0 (24.0–53.0) and late phase = 11.0 (8.0–14.0)). 63SF administered orally exhibited an antinociceptive effect in the formalin test (ID50 first phase = 125.0 (89.0–177.0) and late phase = 65.0 (33.0–95.0)). In the same test, 63SF was effective when given soon after the first phase, as well as exhibiting therapeutic activity. Furthermore, 63SF was effective in models of thermal nociception including tail-flick and hot-plate tests. When the mice were treated in the neonatal period with capsaicin, the antinociceptive effect of 63SF in the first phase of the formalin test was abolished, but pretreatment with naltrexone did not change the antinociceptive effect of 63SF. Together, these results provide evidence that 63SF exerted a pronounced systemic antinociception against chemical (acetic acid, formalin, glutamate and capsaicin tests) and thermal (hot-plate and tail-flick tests) nociceptive models of pain in mice at a dose that did not interfere with the locomotor activity. The mechanism by which this sub-fraction produced antinociception remains unclear, but it is unlikely to involve the activation of the opioid system. However, unmyelinated C-fibres sensitive to treatment with capsaicin are likely to participate in antinociception caused by 63SF.

Uncaria tomentosa (Willd.) DC (Rubiaceae) is a vine that grows in the Amazon rainforest. Its bark decoctions are used by Peruvian Indians to treat several diseases. Chemically, it consists mainly of oxindole alkaloids. An industrial fraction of U. tomentosa (UT fraction), containing 95% oxindole alkaloids, was used in this study in order to characterize its antinociceptive activity in chemical (acetic acid-induced abdominal writhing, formalin and capsaicin tests) and thermal (tail-flick and hot-plate tests) models of nociception in mice. UT fraction given by the i.p. route dose-dependently suppressed the behavioural response to the chemical stimuli in the models indicated and increased latencies in the thermal stimuli models. The antinociception caused by UT fraction in the formalin test was significantly attenuated by i.p. treatment of mice with ketanserin (5-HT2 receptor antagonist), but was not affected by naltrexone (opioid receptor antagonist), atropine (a nonselective muscarinic antagonist), l-arginine (precursor of nitric oxide), prazosin (alpha1-adrenoceptor antagonist), yohimbine (alpha2-adrenoceptor antagonist), and reserpine (a monoamine depleter). Together, these results indicate that UT fraction produces dose-related antinociception in several models of chemical and thermal pain through mechanisms that involve an interaction with 5-HT2 receptors.

This study investigated the superoxide anion and hydroxyl radical scavenger properties, as well as the inhibition of lipid peroxidation by the crude hydroalcoholic extract (CE) and the butanolic (BF) and ethyl acetate (EAF) fractions of Cuphea carthagenensis leaves. In a enzymatic system of O 2 − production (xanthine/xanthine oxidase system) the CE, EAF and BF (0.1–100 μg ml −1 ) were effective at inhibiting both uric acid formation and NBT reduction by O 2 −1 . In the non-enzymatic system of O 2 − generation, the CE and fractions were effective only at the concentration of 100 μg ml −1 . The CE, EAF and BF were also evaluated for their ability to scavenge hydroxyl radicals and/or to chelate iron. The results showed that CE, BF and EAF from C. carthagenensis (0.1–100 μg ml −1 ) were able to inhibit deoxyribose degradation in a concentration-dependent manner. CE was more potent than the fractions. In a hydrophobic system, increasing concentrations of CE, EAF and BF (0.1–100 μg ml −1 ) caused graded inhibition of lipid peroxidation of rat liver homogenate. The EAF displayed the lowest median inhibitory concentration. The present study suggests that an extract (CE) and fractions (EAF and BF) from C. carthagenensis leaves are significant sources of phenolic compounds with antioxidant activity in vitro and may have important health effects, for example, in cardiovascular disease.

Croton celtidifolius Baill (Euphorbiaceae) is a tree found in the Atlantic forest of southern Brazil. This plant is used in folk medicine for the treatment of several inflammatory diseases, leukaemia, ulcers and other pathologies. Previous studies demonstrated anti-inflammatory and antioxidant activities and the objective of this work was to investigate a possible antinociceptive action of ethanolic extract of Croton celtidifolius bark (EE) and ethyl acetate fraction (EAF), n-butanol fraction (FBuOH), and aqueous fraction (FAq) obtained from EE. Two standard rodent models of pain were employed for this investigation, the writhing test and the formalin test. In the writhing test, the pre-treatment with EE significantly reduced the writhing induced by 0.6% acetic acid injection and its effect persisted for 4 h. In the formalin test, the pre-treatment with EAF caused marked and dose-related inhibition of formalin-induced licking in mice in the first phase, while pre-treatment with EAF, FBuOH and FAq had a similar effect in the second phase, when given by intraperitoneal (i.p.) and orally (p.o.) route. However, given by i.p. route, the effect of fractions was about three to five-fold more potent in inhibiting licking than when administered by p.o. route. EE presented an antinociceptive effect only in the second phase, when given by i.p. or p.o. route. The oedema caused by formalin was significantly reduced in animals treated i.p. with EAF, FBuOH and FAq. Under the same experimental conditions, in animals treated with sub-fractions derived from EAF only the 63 sub-fraction significantly reduced nociception in both phases and oedema caused by formalin. The results obtained suggest that Croton celtidifolius possesses antinociceptive properties since the EE, fractions and a sub-fraction significantly reduced the writhing induced by acetic acid and the nociception in both phases of the formalin test.

Mouse paw oedema induced by carrageenan is used to determine if glucocorticoids are involved in the anti-inflammatory effects of peripheral benzodiazepine receptor ligands. The anti-inflammatory responses elicited by i.p. treatment with 1-(2-chlorophenyl)-N-methyl-N (1-methyl-propyl)-3-isoquinoline carboxamide (PK11195) and 7-chloro-5-(4-chlorophenyl)-1,3-dihydro-1-methyl-2-H-1, 4-benzodiazepin-2 (Ro5-4864) were reversed by aminoglutethimide, an inhibitor of steroidal synthesis. Intraplantar injection into the ipsilateral paw of Ro5-4864, but not PK11195, inhibited the formation of paw oedema and this effect was reversed by aminoglutethimide. These results suggest that glucocorticoids are involved in the systemic and local anti-inflammatory effects of Ro5-4864 and only in the systemic response to PK11195.

The effect of valeryl salicylate (VS), an inhibitor of cyclooxygenase-1 (COX-1), was evaluated in arachidonic acid or croton oil-induced ear oedema and carrageenan-induced paw oedema in mice. Ear oedema was induced by topical administration of arachidonic acid (2mg per ear; 20 microliters) or croton oil (1mg per ear; 20 microliters) to the inner surface of the left ear and the change in the ear's thickness was measured with a precision micrometer (Fisher, USA). VS significantly inhibited the arachidonic acid ear oedema after lh at doses of 1.5-45 micrograms per ear; however, only at the dose of 45 micrograms per ear was it able to significantly reduce the croton oil-induced oedema at 6h. Paw oedema was induced by the injection of 25 microliters of 1% carrageenan into the plantar aponeurosis of the right hind paw. The oedema was evaluated at 0.5, 1, 2, 4, 24, 48 and 72h. Previously in our experiments, we observed two peaks in paw oedema formation: one at 2h, in the early phase (0-4h), and the other, occurring at 48h after carrageenan injection, in the late phase (24-72h). The pre-treatment with VS significantly reduced the paw oedema at 2h, the same effect observed with celecoxib and indomethacin treatments. At 24h, VS did not inhibit oedema but significantly increased it mainly at 48h after carrageenan injection. These results showed that VS was pharmacologically active in these models and suggest that COX-1 may participate in the early and late phases of inflammation in the models studied.

This study evaluated the vasorelaxant properties of the crude hydroalcoholic extract (CE) of Cuphea carthagenensis, as well as its butanolic (BF) and ethyl acetate (EA) fractions, in rings of rat thoracic aorta. In endothelium-intact rings contracted with phenylephrine (30-100 nM), cumulative additions of increasing concentrations of CE, BF, and EA of C. carthagenensis (0.1 microg/ml-3 mg/ml) caused graded relaxations, with BF displaying the lowest median inhibitory concentration (IC5; mean, 6.8 microg/ml; 95% confidence limits, 3.3-14.2). BF-induced relaxations of endothelium-intact rings were virtually abolished by prior incubation with the NO-synthase inhibitor N(omega)-nitro-L-arginine (L-NOARG; 10 or 30 microM), and were markedly reduced after guanylate cyclase inhibition with either methylene blue (10 microM) or ODQ (1 microM; 1H[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one). The inhibition of BF-induced relaxation by L-NOARG was prevented to a large extent by simultaneous incubation with L-arginine (1 mM). In endothelium-denuded rings contracted with phenylephrine, CE and BF caused graded relaxations only at doses >100 microg/ml, whereas the NO-donors SNAP (S-nitroso-N-acetyl-penicillamine) and SIN-1 (3-morpholino-sydnonimine) induced full relaxation at 1 microM. BF (100 microg/ml), which caused little relaxation per se of endothelium-denuded rings, potentiated the relaxant effects of SNAP and even more so of SIN-1 (which, unlike SNAP, also releases superoxide anion O2- in addition to NO), in a manner qualitatively similar to that seen with SOD (superoxide dismutase) against SIN-1. These data indicate that the BF of C. carthagenensis induces relaxation of the rat thoracic aorta by two mechanisms: (a) an endothelium-dependent component of action, which clearly depends on the NO/cyclic guanosine monophosphate (cGMP) pathway and can be attributed, at least in part, to free radical-scavenging properties; and (b) an endothelium-independent component of action, which becomes evident at higher doses (> or = 100 microg/ml) and remains to be further characterized. These results suggest that this native South American plant might be beneficial in cardiovascular disease.

This study investigates the anti-inflammatory effects of 1-(2-chlorophenyl)-N-methyl-N(1-methylpropyl)-3-isoquinoline carboxamide and 7-chloro-5-(4-chlorophenyl)-1, 3-dihydro-1-methyl-2-H-1,4-benzodiazepin-2-one in paw oedema induced by carrageenan in mice. Pretreatment (24 h) with both ligands inhibited oedema formation in at different doses (0.00001-10 mg/kg, i.p.) with range of inhibition of 25% to 70%, in animals with or without adrenal glands. These results demonstrate, for the first time, an in vivo anti-inflammatory property of peripheral benzodiazepine receptor ligands.

This study has evaluated the possible role played by the l-arginine-nitric oxide pathway in the vasorelaxant action of the hydroalcoholic extract from Eugenia uniflora, and fractions from the extract, in rings of rat thoracic aorta. The addition of an increasing cumulative concentration of hydroalcoholic extract from E. uniflora (1–300 μg mL−1) caused a concentration-dependent relaxation response in intact endothelium-thoracic aorta rings pre-contracted with noradrenaline (30–100 nm). The IC50 value, with its respective confidence limit, and the maximum relaxation (Rmax) were 7.02 (4.77–10.00) μg mL−1 and 83.94 ± 3.04%, respectively. The removal of the endothelium completely abolished these responses. The nitric oxide synthase inhibitors Nω-nitro-l-arginine (l-NOARG, 30 μm) and Nω-nitro-l-arginine methyl ester (l-NAME, 30 μm), inhibited the relaxation (Rmax) to −10.43 ± 7.81% and −3.69 ± 2.62%, respectively. In addition, l-arginine (1 mm), but not d-arginine (1 mm), completely reversed inhibition by l-NOARG. Methylene blue (30 μm), a soluble guanylate cyclase inhibitor, reduced the relaxation induced by the extract to 14.60 ± 7.40%. These data indicate that in the rat thoracic aorta the hydroalcoholic extract, and its fractions, from the leaves of E. uniflora have graded and endothelium-dependent vasorelaxant effects.

Portulaca pilosa has been used in Brazil as a traditional remedy to cause diuresis, antipyresis and analgesia. Achyrocline satureioides has been used in folk medicine as antiinflammatory, hypoglycemic, sedative and to treat gastrointestinal disorders such as diarrhea and dysentery suggesting that it may affect salt and water reabsorption by the gastrointestinal tract. In the current study, hydroalcoholic extracts of both plants were investigated in order to examine their renal effects. The results support the claim that extracts of P. pilosa present renal effects but not the popular belief that it affects diuresis. It has also been proved that, in rats, it causes an increase in K excretion without a concomitant change in water diuresis or Na excretion. Our findings also support the popular belief that A. satureioides does not apparently have renal effects and it might change renal ion transport based on observations that it affects gastrointestinal reabsorption.

Cell wall polysaccharides of the red algae Laurencia microcladia were isolated by alkaline treatment (KOH 1M, 10 mg NaBH4, room temperature), yielding two sub-fractions by neutralization (AcOH, pH=5.2) and EtOH precipitation, respectively A and B. Paper electrophoresis revealed the existence of only one polysaccharide in each fraction. FT-IR spectra of both polysaccharides showed signals for COH (OH: 3400-3300 cm-, CO: 1260-1000 cm-) and CHC (1300 – 1000 cm-) typical of cell wall algal polymers. An N-glyco derivative (1640 – 1560 cm-) and a low acidic content (0.34 mol %) were structural features found, while proteins were not detected. Antimitotic activity was observed on Lytechinus variegatus (green bur) larvae, with chronic values of 38.18 mg/mL and 267.99 mg/mL for polysaccharides A and B, respectively. No bradykinin or acetylcholine antagonistic effect was observed when polysaccharides were assayed in vitro in guinea-pig ileum. Preliminary results pointed to neurotoxic effect of these macromolecules (5mg/100 mL) since asymmetry of the neural tube in chick embryo was also found.

Foram efetuados estudos químicos e farmacológicos dos extratos brutos hidroalcóolicos obtidos das folhas ou das raízes de E. argentinum ou de frações semi-purificadas desta planta. Os testes químicos revelaram a existência de alcalóides, fitoesteróides, leucoantocianidinas, glicosídeos flavonóides, cumarinas e taninos. A análise farmacológica in vivo demonstrou que o extrato das folhas é menos tóxico que o da raiz. Tanto o extrato bruto como as frações semi-purificadas obtidas das folhas reduziram a locomoção e pressão arterial de rato e potenciaram o sono barbiturico em camundongos. O extrato bruto, principalmente o da raiz, reduziu o edema induzido por carragenina na pata de rato. Testes in vitro demonstraram que o extrato bruto ou as frações semi-purificadas das folhas produziram uma ação semelhante à cocaína avaliada no canal deferente de rato. Além disso, o extrato bruto produziu relaxamento inespecífico no útero de rata e contração do íleo de cobaia. Os resultados obtidos sugerem que esta planta possui constituintes ativos dotados de distintas propriedades farmacológicas, destacando-se o efeito anti-inflamatório, além de uma ação tipo cocaína, merecendo, portanto, estudos químicos e farmacológicos complementares. Chemical and pharmacological studies were carried out using crude hydroalcholic extracts obtained from the leaves or roots of E. argentinum or the semipurified fractions of this plant. Chemical analysis detected the presence of alkaloids, phytosteroids, leucoanthocianidins, flavonoid glycosides, cumarins and tannins. Qualitatively similar pharmacological effects were observed in experiments using both extracts from the leaves or roots. Experiments in vivo revealed that the crude extract and the semipurified fractions from the leaves reduced locomotor activity, blood pressure, carragenin-induced paw edema and potentiated barbiturate-induced sleeping-time in laboratory animals. In vitro studies demonstrated that the leaf extract or the semipurified fractions induced a cocaine-like effects on the rat vas deferens, a non-specific relaxation of the rat uteri and a contraction of the guinea-pig ileum. It is concluded that E. argentinum contains active compounds responsible for the antiinflammatory effect and cocaine-like action observed in vitro, which merit emphasis in future research.

Antidiabetic activity of crude extract of leaves of Talauma ovata St. Hil. (Magnoliaceae) was analysed as part of a general pharmacological screening of this plant. Chemical analysis demonstrated the presence of phytosteroids, saponins, alkaloids and tannins in the crude extract. Pharmacological studies failed to demonstrate hypoglycemic effect of this plant in normoglycemic, hyperglycemic or alloxan-diabetic rats. The low LD50 obtained for this plant strongly suggests that its consumption by the population may be hazardous.

The aim of this study is to investigate the effect of Cecropia glaziovii Snethl, Urticaceae, extracts on the oral glucose tolerance curve, on glycemia in alloxan-induced diabetic rats and vasorelaxant effect after the extraction process, and to standardize the extractive solutions. The effects of the process variables and their interactions were calculated in relation to dry residue, pH, total phenolic results and chemical marker content. Furthermore, the effect of the extracts (400 mg/kg), chlorogenic (2 or 15 mg/kg) and caffeic acids (2 mg/kg) were investigated on the oral glucose tolerance curve and on glycemia in alloxan-induced diabetic rats. Oral administration of ethanol extracts 4d20 and 8d20 significantly improved glucose tolerance in the hyperglycemic rats. Chlorogenic and caffeic acids, as well as the association of the compounds were able to significantly reduce glycemia after oral gavage treatments. On the other hand, the aqueous extracts did not alter the glycemia. The aqueous extracts (8020 and 9030) and only the higher dose of chlorogenic acid presented a significant effect on serum glucose lowering in diabetic rats. Additionally, the IC50 reveals that the ethanol extracts presented more potent vasodilator effects than the aqueous extracts in aortic rings. This study shows that C. glaziovii standardized extracts exhibits antihyperglycemic action, is able to improve glucose tolerance and has a potent vascular relaxing effect. These results are probably linked to concentrations of the main phenolic compounds of the extracts. Keywords: Cecropia glaziovii, Decoction, Maceration, Total phenolic, Antihyperglycemic activity, Vasorelaxant activity

Estudos de nosso laboratório surgerem que o ácido tânico (AT) exerce diversos efeitos "in vitro" ou "in vivo", podendo ser responsável por várias ações inespecíficas freqüentemente observadas com extratos brutos de plantas medicinais. O presente trabalho amplia estes estudos em outos modelos biológicos. A administração crônica ou aguda, por vida oral (v.o.), de AT em ratos não produziu alterações gástricas ou no processo inflamatório. Em ratos não-diabéticos observou-se modificações variáveis na glicemia de acordo com a metodologia empregada. O AT, cronicamente (v.o.), não interferiu na reprodução de fêmeas, embora constatou-se redução do número de filhotes de machos tratados. O AT (3mg/kg, v.o.) provocou aumento da diurese, porém doses mais elevadas não modificaram o volume urinário. Os testes hematológicos demonstraram que o AT possui efeito anticoagulante "in vitro", sem modificar a fragilidade de hemácias ou na homeastase sanguínea "in vivo". No músculo esquelético, o AT reduziu a resposta contrátil à acetilcolina, enquanto no músculo cardíaco (átrio esquerdo) observou-se efeito inotrópico positivo ou negativo. Estes resultados estendem os estudos anteriores e reforçam a sugestão de que parte significativa dos efeitos inespecíficos observados com extratos brutos de plantas medicinais podem estar relacionados com a presença de taninos nos mesmos. Extending previous studies the present report analyses the pharmacological effects of tannic acid (TA) in several tests. TA prevented carragenin-induced edema when administered by i.p. but not p.o. route. Long term p.o. treatment with TA did not induce gastric lesions and showed inconsistent effects on glicemia in non-diabetic rats. Rats chronically exposed to TA during the fetal stage or following birth did not exhbit changes in gain of or organ weights, but adult male rats showed a lower fertility ratio. Urinary output was slightly increased by administration of a small dose of TA (3mg/kg, p.o.), but not by higher doses. The addition of TA "in vitro" to blood samples did not influence osmotic fragility but prevented clotting for at least 30 min. In isolated tissues, TA non competitively antagonized acetylcholineinduced contractions of the frog rectus-abdominal muscle and induced, depending of the dose, both positive and negative inotropic effects in the electrically-stimulated left rat atrium. These results confirm and extend our previous observations and suggest that a great number of non-specific effects detected in studies on the pharmacology of different folk medicinal plants may be related to the presence of tannins.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Farmacologia, Florianópolis, 2011 A aterosclerose é uma doença progressiva caracterizada pelo acúmulo de lipídios e elementos fibrosos nas artérias de médio e grande calibre. As doenças cardiovasculares decorrentes da aterosclerose, dentre elas o infarto agudo do miocárdio e o acidente vascular cerebral, são a principal causa de mortalidade e morbidade mundial. O estresse oxidativo e a deficiência da enzima glutationa peroxidase (GPx) possuem um importante papel no desenvolvimento da aterosclerose. Neste contexto, o objetivo deste trabalho foi avaliar o efeito do disseleneto de difenila (DD), um composto orgânico de selênio, em modelos experimentais de aterosclerose, in vivo e in vitro. O tratamento com baixas doses de DD (0,1 e 1 mg/kg/dia, v.o.) por 30 dias reduziu a formação de lesões ateroscleróticas em camundongos com deleção gênica para o receptor da lipoproteína de baixa densidade (LDLr -/-) submetidos a uma dieta hipercolesterolêmica. Esta redução foi acompanhada por melhora na vasodilatação dependente do endotélio, diminuição da expressão de 3-nitrotirosina e malondialdeído (marcadores de estresse oxidativo), redução da razão colesterol não-HDL/HDL, diminuição da infiltração de células inflamatórias na lesão e dos níveis sistêmicos de MCP-1. Em cultura de células endoteliais de aorta bovina (BAECs), o pré-tratamento por 24 horas com DD (0,5 e 1 M) atenuou a apoptose induzida por LDL humana isolada associada à diminuição da formação de EROs e o consumo de GSH, e restabelecer o aumento do potencial de membrana mitocondrial. Os estudos em macrófagos murinos da linhagem J774 expostos a oxLDL (100 g/mL), demonstraram que o DD (1 M) reduziu significativamente a formação de células espumosas, a produção de EROs e de mediadores inflamatórios (MCP-1 e TNF- ). Este conjunto de resultados revela o potencial antiaterogênico do DD, tanto em modelos experimentais in vivo quanto in vitro. Os efeitos demonstrados pelo composto sugerem ser relacionados às suas propriedades antioxidante, mimética da GPx e anti-inflamatória.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Farmacologia, Florianópolis, 2009.

Doutoramento em Química Esta tese centra-se no desenvolvimento de materiais biodegradáveis e nãodegradáveis produzidos por eletrofiação com aplicação na área biomédica. O poli(3-hidroxibutirato-co-3-hidroxivalerato) (PHBV), um poliéster biodegradável, foi selecionado como base dos materiais biodegradáveis, enquanto o poli(tereftalato de etileno) (PET), um polímero sintético, estável e biocompatível, foi selecionado para a produção das matrizes não degradáveis. Adicionou-se quitosana aos sistemas com o objetivo de melhorar o processo de eletrofiação e as propriedades morfológicas, físico-químicas e biológicas dos materiais resultantes. A composição química, bem como as características morfológicas e físicoquímicas dos materiais em estudo, foram manipuladas de modo a otimizar a sua performance como suportes celulares para engenharia de tecidos. Foram realizados estudos in vitro com cultura de fibroblastos L929 para avaliar o comportamento das células, i.e. viabilidade, adesão, proliferação e morte, quando cultivadas nas matrizes produzidas por eletrofiação. Adicionalmente foram realizados ensaios in vivo para investigar o potencial dos materiais em estudo na regeneração cutânea e como tela abdominal. Os principais resultados encontrados incluem: o desenvolvimento de novas matrizes híbridas (PHBV/quitosana) adequadas ao crescimento de fibroblastos e ao tratamento de lesões de pele; o desenvolvimento de um sistema de eletrofiação com duas seringas para a incorporação de compostos bioativos; diversas estratégias para manipulação das características morfológicas dos materiais de PHBV/quitosana e PET/quitosana produzidos por eletrofiação; uma melhoria do conhecimento das interações fibroblastos-suporte polimérico; a verificação de uma resposta inflamatória desencadeada pelos materiais nãodegradáveis quando utilizados no tratamento de defeitos da parede abdominal, o que sugere a necessidade de novos estudos para avaliar a segurança do uso de biomateriais produzidos por eletrofiação. This thesis focuses on the development of biodegradable and non-degradable electrospun materials with application in the biomedical field. Poly(3- hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), a natural biodegradable polyester, was selected as the basis of the biodegradable materials while polyethylene terephthalate (PET), a biocompatible stable synthetic polyester, was selected for the production of the non-degradable ones. Chitosan was added to both systems in order to enhance electrospinnability as well as morphological, physico-chemical, and biological features of the biomaterials. The chemical composition, morphological and some physico-chemical characteristics of these materials were manipulated toward an optimized biological performance as scaffolds for tissue engineering. In vitro cell culture studies were performed with L929 fibroblasts in order to study the cell behavior, i.e. viability, adhesion, proliferation and death, when cultured on the electrospun materials. Furthermore, in vivo assays were conducted in order to investigate the potential of the materials under study for skin and abdominal wall repair. The main achievements of this thesis include: the development of new PHBV/chitosan hybrid mats suitable for fibroblasts growth and with a good performance when used as a scaffold for skin repair; the development of a dual syringe electrospinning system for incorporation of bioactive compounds; several strategies to manipulate the morphological characteristics of electrospun materials of both PHBV/chitosan and PET/chitosan blends; an improvement of the knowledge of cell-scaffolds interactions; the detection of an important inflammatory response elicited by the non-degradable electrospun materials when used as prosthetic meshes for abdominal defect repair, suggesting the need of further studies on the safety of nanosized electrospun biomaterials.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-Graduação em Farmacologia. Glutamato, o principal neurotransmissor central excitatório, induz excitotoxicidade neuronal pela ativação de receptores NMDA e AMPA, promovendo o influxo de cálcio nos neurônios. Estudos recentes do nosso grupo demonstram que as frações e sub-frações isoladas da Croton celtidifolius possuem propriedades anti-inflamatórias, antioxidantes e antinociceptivas. Assim, utilizando um modelo in vitro de excitotoxicidade induzida por glutamato (Glu) e in vivo de neurotoxicidade decorrente da lesão da medula espinhal de ratos Wistar adultos, avaliou-se o possível efeito neuroprotetor da fração rica (FRP) em proantocianidinas isolada da Croton celtidifolius. Glu induziu morte de células do gânglio da raiz dorsal (GRD), de forma dependente da concentração e do tempo de exposição. O pós-tratamento com a FRP (1 - 100 µg/ml) inibiu em até 37% a morte celular induzida por Glu (1 mM). Já o co-tratamento, foi capaz de reduzir a morte celular em 27%. A exposição das células ao Glu (0,01, 0,1 e 1 mM) aumentou os níveis da enzima lactato desidrogenase de 6,5 % (células controle) para 37, 49 e 63 %, respectivamente, indicativo de alteração na permeabilidade da membrana celular. Esta alteração foi atenuada pelo tratamento das células com a FRP (100 µg/mL). Ademais, o insulto glutamatérgico induziu a geração de espécies reativas de oxigênio, a qual foi inibida pelo tratamento das células do GRD com FRP (100 µg/ml). Além disso, o efeito neuroprotetor desencadeado pela FRP parece ser mediado em parte pela inibição de receptores glutamatérgicos do tipo NMDA, mas não os metabotrópicos uma vez que a perda da viabilidade celular decorrentes da exposição das células ao agonista NMDA, mas não ao agonista metabotrópico, foi revertida pela FRP. Nos estudos in vivo, animais submetidos a lesão medular e tratados com a FRP na dose de 10 mg/kg por via intraperitoneal, durante 5 dias consecutivos, apresentaram uma melhora significante na performance locomotora e na força de preensão, quando comparado aos animais lesados tratados com veículo. Em conjunto, estes resultados fornecem a primeira evidência de que a FRP atenua a morte celular por necrose e por apoptose, bem como a produção de EROs induzida por Glu, inibe a morte celular induzida por peróxido de hidrogênio e pelo agonista NMDA. A FRP também foi capaz de promover uma melhora na atividade locomotora e na força de preensão de animais submetidos à lesão traumática da medula espinhal, reforçando a hipótese de que polifenóis podem ser ferramentas terapêuticas promissoras como agentes neuroprotetores. Glutamate, the major central excitatory neurotransmitter, induces neuronal excitotoxicity by activation of NMDA and AMPA receptors and stimulating the influx of calcium into neurons. Recently, our group showed that fractions and subfractions isolated from Croton celtidifolius have antiinflammatory, antioxidant and antinociceptive properties. Thus, using an in vitro model of excitotoxicity induced by glutamate (Glu) and in vivo neurotoxicity caused by spinal cord injury (SCI) in adult Wistar Rats, we evaluated the possible neuroprotective effect of a proanthocyanidin-rich fraction (PRF) isolated from the bark of Croton celtidifolius. Glu induced cell death of dorsal root ganglion (DRG) in a manner concentration-dependent and the exposure time. The post-treatment with FRP (from 1 to 100 ìg / mL) inhibited the cell death induced by Glu (1 mM) in 37%. Since co-treatment, was able to reduce cell death in 27%. The exposure of cells to glu (0.001, 0.1 and 1 mM) increased the levels of the enzyme lactate deydrogenase from 6.5% (control cells) to 37, 49 and 63% respectively, indicating changes in cell membrane permeability. This change was attenuated by treatment of cells with the PRF (100 ìg / mL). Moreover, the glutamatergic insult induced generation of reactive oxygen species, which was inhibited by treatment of cells with FRP (100 ìg / mL). Moreover, the neuroprotective effect triggered by FRP seems to be mediated in part by inhibition of NMDA-type glutamate receptors, but not metabotropic receptors, since the loss of cell viability after exposure of cells to NMDA agonist, but not a metabotropic agonist was reversed by FRP. The in vivo studies, animals subjected to SCI and treated with PRF at a dose of 10 mg / kg by i.p. route for 5 consecutive days showed a significant improvement in locomotor performance and grip force when compared to injured animals treated with vehicle. Taken together, these results provide the first evidence that PRF attenuated the cell death by apoptosis and the production of ROS induced by Glu, also inhibits cell death induced by hydrogen peroxide and the NMDA agonist receptors. The FRP was able to promote an improvement in locomotor activity and grip strength of animals subjected to traumatic spinal cord injury (SCI), reinforcing the hypothesis that polyphenols are promising therapeutic tools such as neuroprotective agents.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Farmacologia, Florianópolis, 2010 No presente estudo investigamos as possíveis propriedades psicofarmacológicas e neuroprotetoras da fração rica em proantocianidinas (FRP) obtida das cascas da Croton celtidifolius Baill (Euphorbiaceae) em ratos. Para tal finalidade, foram utilizados testes comportamentais classicamente empregados na triagem inicial de drogas com atividade sobre o sistema nervoso central e um modelo experimental da doença de Parkinson (DP). A administração intraperitoneal (i.p.) aguda da FRP (10 ou 30 mg/kg) diminuiu significativamente a atividade locomotora espontânea dos animais no campo aberto e na caixa de atividade, e prolongou a duração da hipnose induzida pelo éter etílico, sugerindo um efeito do tipo hipnosedativo. No labirinto em cruz elevado, a FRP (0,3 ou 3 mg/kg) aumentou significativamente a freqüência de entradas nos braços abertos do aparato, indicando um putativo efeito ansiolítico. Além destes efeitos, a FRP (10 ou 30 mg/kg) também aumentou a latência para a primeira convulsão induzida pelo pentilenotetrazol (60 mg/kg; i.p.), induziu ptose palpebral, hipotermia e atenuou o comportamento estereotipado induzido pela apomorfina (0,5 mg/kg; s.c.) na dose de 30 mg/kg. Estes achados sugerem que a FRP possui um amplo espectro de propriedades psicofarmacológicas como hipnosedativa, anticonvulsivante, neuroléptica e ansiolítica. No presente estudo, também foram avaliados os efeitos neuroprotetores do pré-tratamento com a FRP (10 mg/kg; i.p.), durante cinco dias, nas alterações comportamentais e neuroquímicas induzidas pela administração intranasal (i.n.) de MPTP (1 mg/narina) em ratos. A FRP foi capaz de prevenir os prejuízos cognitivos, emocionais e motores induzidos pela administração i.n. do MPTP, como também impediu a inibição da atividade do complexo-I mitocondrial e a degeneração dos neurônios dopaminérgicos do bulbo olfatório e substância negra causados pelo MPTP. Nossos resultados corroboram com outros estudos prévios acerca das propriedades neuroprotetoras dos polifenóis, sugerindo a possibilidade destes compostos serem ferramentas úteis em estratégias de neuroproteção.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-graduação em Farmacologia Uma fração rica em proantocianidinas (FRP) obtida das cascas da C. celtidifolius foi avaliada quanto ao seu potencial vasorrelaxante em preparações vasculares isoladas. Em leito arterial mesentérico, artéria mesentérica e aorta torácica isolados de ratos a FRP induz relaxamento dependente da concentração. Em vasos de pequeno calibre, este efeito foi significativamente reduzido pelo L-NOARG ou por Krebs despolarizante, e completamente abolido quando ambos são combinados. O efeito também foi reduzido na presença de ODQ e pela caribdotoxina. Em vasos de grande calibre, o L-NOARG e o ODQ também reduziram o relaxamento da fração, bem como a ausência de cálcio no e a presença de um bloqueador de influxo de cálcio (lantânio) na solução de Krebs-Henseleit. N-metilmaleimida e a neomicina também foram capazes de reduzir significativamente a vasodilatação induzida pela FRP. Em outro grupo de experimentos, a vasodilatação induzida pela FRP foi significativamente reduzida pelo Wortmannina. A FRP também foi testada quanto ao seu potencial antiaterogênico em camundongos C57/BL6 LDLr KO. Nestes experimentos, a fração não foi capaz de reduzir as concentrações de lipídios séricos (colesterol total, HDL ou VLDL mais LDL), assim como não reverteu os danos vasculares morfofuncionais provocados pela dieta, quando avaliados nos experimentos de reatividade vascular e na determinação da área de lesão aterosclerótica. Os resultados indicam que a FRP apresenta efeito vasorrelaxante dependente de endotélio em artérias de pequeno e grande calibre, que este efeito envolve a ativação da via NO/GMPc e que o mecanismo de ativação da via envolve o influxo de cálcio do meio extracelular pela ativação de proteínas sensíveis ao NEM e via ativação da PLC e por promover hiperpolarização do músculo liso vascular induzido por abertura de canais KCa2+ em vasos de pequeno calibre. A fração também promove a fosforilação da enzima eNOS, pela via PI3K/Akt, mas não apresenta atividade antiaterogênica quando avaliada no modelo de aterogênese induzida pela dieta em camundongos C57/BL6 LDLr KO.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-Graduação em Farmacologia Uncaria tomentosa (Willd.) DC (Rubiaceae) is an indigenous plant of the Amazon rainforest, popularly known as cat#s claw. The medicinal use of this plant by Peruvian indians has drawn scientific interest over its healing propreties, and gave rise to an increasing number of studies about its biological activities. Chemically, the substances of greatest interest present in this plant are indole and oxindole alkaloids. This study characterizes the antinociceptive activity of a standardized fraction of oxindole alkaloids from U. tomentosa (UT) in mouse models of nociception. Pretreatment of animals with UT (3-300 mg/kg, i.p.) decreased, in a dose-dependent way, nociception elicited by chemical stimuli such as the intraperitoneal injection of acetic acid and the intraplantar injection of formalin, glutamate or capsaicin. Treatment with UT (300 mg/kg) significantly increased the latency of animals to respond to thermal noxious stimuli (hot plate and tail flick tests), probably revealing central effects of the alkaloids. Moreover, treatment with UT was able to inhibit nociceptive behavior caused by intratecal injection of glutamate, NMDA, substance P and the proinflammatory cytokines TNF-á and IL-1â. The antinociceptive effect of UT (100 mg/kg, i.p.) in the formalin test was abolished by pretreatment with ketanserin, an antagonist of serotonergic 5-HT2 receptors, but not by antagonists of the opioid receptors (naltrexone), muscarinic cholinergic receptors (atropine), or adrenergic á1 and á2 receptors (prazosin and yoimbine, respectively). In a similar way, pre-treatment with L-arginine, a substrate for the nitric oxide synthase enzyme, did not affect the antinociceptive activity of UT in the formalin test. These data suggest that the antinociceptive activity of UT involves an interaction with the serotonergic and the glutamatergic systems, but not with the other systems tested here.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-Graduação em Farmacologia O estresse oxidativo desempenha um importante papel na patogênese de várias doenças humanas, tais como injúria por isquemia e reperfusão, aterosclerose, doenças neurodegenerativas e câncer. No sistema cardiovascular, os radicais livres estão envolvidos principalmente no desenvolvimento da hipertensão e aterosclerose. Neste contexto, o presente trabalho teve como objetivo investigar, in vitro e in vivo, a atividade antioxidante de Cyathea phalerata, além de sua atividade vasodilatadora em anéis de aorta torácica isolada de rato. A atividade antioxidante in vitro foi avaliada através da medida da capacidade seqüestradora do Extrato Bruto (EB), Precipitado (PPT), Fração Aquosa (FAQ), Fração n-Butanol (FBU) e Fração Acetato de Etila (FAE), sobre os radicais DPPH, O2"- e OH", e sobre a peroxidação lipídica. Nestes ensaios foi possível observar o relevante potencial antioxidante da FAE, principalmente a sua capacidade de captar o radical OH" e inibir a peroxidação lipídica. A avaliação in vivo do estresse oxidativo foi realizada em camundongos pré-tratados com a FAE (10, 30 ou 100 mg/kg) e posteriormente expostos ao tetracloreto de carbono (CCl4), através da medida ex vivo de fragmentação do DNA, carbonilação de proteínas e lipoperoxidação de membranas, e das defesas antioxidantes (concentração de GSH e atividades de CAT e GST). A FAE foi capaz de reduzir o dano induzido pelo agente estressor (CCl4) ao DNA, lipídeos e proteínas e aumentar a atividade das enzimas CAT e GST. O importante potencial antioxidante apresentado pela FAE de Cyathea phalerata levou ao estudo desta fração em um modelo de reatividade vascular in vitro (aorta torácica isolada de ratos). A FAE apresentou um efeito vasodilatador dependente da camada de células endoteliais, principalmente nas menores concentrações. A incubação prévia com L-NOARG e ODQ demonstrou a participação da via NO/GMPc no efeito vasodilatador desta fração. Além disso, prostaciclina produzida pelas células endoteliais também parece participar desta atividade. A FAE não alterou a contração induzida pela fenilefrina e nem o relaxamento induzido pelo SNP. O relevante potencial antioxidante e a atividade vasodilatadora de Cyathea phalerata podem estar relacionados à sua composição química, rica em flavonóides. Esta planta pode ser importante para o tratamento de patologias que envolvem estresse oxidativo, podendo diminuir os dano causados à macromoléculas (lipídeos, proteínas e DNA) e aumentar as defesas antioxidantes. Destaca-se a importância da FAE de Cyathea phalerata, rica em flavonóides, para a prevenção e tratamento de doenças cardiovasculares.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-Graduação em Farmacologia O objetivo geral deste estudo foi investigar a atividade de uma fração rica em compostos fenólicos - Fração Acetato de Etila (FAE), obtida a partir do extrato bruto dealcoolizado de um [vinho] tinto catarinense, sobre o sistema cardiovascular de ratos Wistar normotensos e camundongos C57/BLACK6 com ablação gênica para o receptor de LDL (LDLR KO), submetidos a uma dieta hipercolesterolêmica (DH). Foram realizados ensaios para determinar a atividade [antioxidante], experimentos de reatividade vascular, experimento crônico para verificar o efeito da FAE em camundongos LDLR KO submetidos a uma DH, dosagens bioquímicas de [colesterol] total, triglicerídeos, e lipoproteínas, cortes histológicos de arcos aórticos de camundongos LDLR KO para determinar a formação de [ateromas] e imunohistoquímica. Os resultados deste estudo demonstraram que a FAE apresenta alguns efeitos biológicos importantes: 1) atividade [antioxidante] in vitro; 2) atividade vasorelaxante sobre vasos de pequeno calibre, mais precisamente, sobre o leito arterial mesentérico de ratos; 3) efeito hipolipidemiante na menor dose utilizada (3 mg/kg); 4) Diminuição sobre a expressão dos marcadores CD40L e nitrotirosina (N-TYR). A diminuição da expressão dos referidos marcadores aterogênicos foi ao encontro de todos os demais resultados anteriores, confirmando as efetivas atividades antioxidantes, hipolipidemiantes e vasorelaxantes da FAE.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-graduação em Farmacologia O tratamento in vivo em camundongos com ligantes do receptor periférico benzodiazepínico (PBR) exerceram efeito inibitório na resposta inflamatória em dois modelos de inflamação aguda. No primeiro modelo o efeito antiinflamatório em de pré-tratamento com os ligantes PBR, PK11195 1-(2-chlorophenyl)-N-methyl-N(1-methylpropyl)-3-isoquinoline carboxamide e Ro5-4864 7-chloro-5-(4-Chlorophenyl)-1,3-dihydro-1-methyl-2-H-1,4-benzodiazepin-2, mostraram que a formação do edema em resposta a carragenina (300 mg/pata) foi inibida por PK11195 e Ro5-4864, em diferentes intervalos de tempo. O estudo do tempo resposta mostrou que a melhor resposta com ambos ligantes foi ótima em animais injetados no tempo de 24h, por esta razão este tempo de pré-tratamento foi escolhido para estudo da dose resposta. A formação do edema de pata em resposta a carragenina (300 mg/pata) foi reduzida por PK11195 e Ro5-4864 em diferentes doses (0,00001-10mg/kg, i.p.) produzindo uma inibição dose dependente na formação do edema de pata em camundongos induzida pela carragenina. PK11195 e Ro5-4864 (0.1 mg/kg, i.p.) quando administrado 24 h antes da indução do edema, inibiram de forma significativa o edema de pata de camundongos induzido por vários mediadores inflamatórios. No segundo modelo o pré-tratamento com os ligantes (0.1 mg/kg, i.p.), 24 h antes da indução da pleurisia induzida pela carragenina, mostrou uma significante inibição no recrutamento das células totais e diferenciais, principalmente a custas de neutrófilos, inibindo também a liberação de Interleucina-13 (IL-13) e Interleucina-6 (IL-6) no líquido pleural

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em Farmácia A disfunção endotelial e o envolvimento de radicais livres exercem um importante papel na patogênese da aterosclerose. A erva-mate (Ilex paraguariensis) apresenta atividade antioxidante e vasorelaxante in vitro, em leito arterial mesentérico de ratos e reduz a aterosclerose experimental em coelhos. Assim, o objetivo deste trabalho foi verificar o efeito do extrato aquoso de Ilex paraguariensis (EAI) i) na confirmação da atividade antioxidante in vitro do extrato utilizado; ii) no relaxamento in vitro de aorta torácica de ratos e; iii) na reatividade vascular ex vivo de camundongos com aterosclerose. A atividade antioxidante do EAI foi avaliada através dos ensaios de redução do NBT, degradação da desoxirribose e inibição da peroxidação lipídica. O EAI mostrou-se efetivo em todos os ensaios, de maneira dependente da sua concentração (p < 0,01). No relaxamento in vitro de aortas torácicas de ratos, previamente contraídas com fenilefrina, o EAI apresentou efeito significativo dependente da sua concentração na presença de endotélio funcional (p < 0,01). O relaxamento na ausência de endotélio íntegro ocorreu somente com as maiores concentrações de EAI avaliadas. Ensaios realizados com o inibidor das enzimas óxido nítrico sintases, L-NOARG, e com o substrato endógeno, L-arginina, sugeriram o envolvimento da via NO/GMPc no relaxamento dependente de endotélio induzido pelo EAI. O efeito do EAI na reatividade vascular ex vivo foi testado em camundongos "knockout" para o receptor de LDL (LDLR KO) administrados com 3 diferentes doses do EAI. Os animais foram distribuídos em 5 grupos (n = 7 por grupo): 1) controle (C), dieta padrão e água ad libitum; 2) hipercolesterolêmico (HC), dieta com 1,25 % de colesterol e água; 3), 4) e 5) hipercolesterolêmico-Ilex paraguariensis (HI), dieta com colesterol e EAI nas doses de 0,3, 0,9 e 2,7 g/kg/dia, respectivamente. Após 3 meses de tratamento, os camundongos do grupo HC apresentaram valores séricos de colesterol total e de LDL e VLDL significativamente elevados (p < 0,001). A administração do EAI não modificou o perfil lipídico dos animais dos grupos HI nas três doses estudadas. As artérias dos camundongos HC apresentaram estrias gordurosas e diminuição significativa na resposta de contração à fenilefrina e relaxamento à acetilcolina (p < 0,001). O tratamento com EAI reverteu a inibição da capacidade contrátil da aorta nos grupos HI 0,9 e HI 2,7 e de inibição do relaxamento no grupo HI 0,9 (p < 0,05). Em conclusão, os resultados mostraram que o EAI comercial possui atividade antioxidante e vasorelaxante in vitro, com envolvimento do NO endotelial. Além disso, a ingestão do EAI melhorou a reatividade vascular ex vivo de aortas de camundongos LDLR KO com aterosclerose, apesar da hipercolesterolemia. Tais resultados são sugestivos do potencial benéfico da erva-mate no combate à aterosclerose. Endothelial dysfunction and free radicals play an important role in the pathogenesis of atherosclerosis. "Mate" (Ilex paraguariensis) extract exhibits antioxidant activity and induce endothelium-dependent vasodilatation in mesenterical arterial bed in vitro and reduces experimental atherosclerosis in cholesterol-fed rabbits. Therefore, this study assessed the effects of a commercial Ilex paraguariensis aqueous extract (IAE) on i) the confirmation of in vitro antioxidant activity of the extract used; ii) vasodilatation of thoracic rat aortas and iii) ex vivo vascular reactivity in atherosclerotic mice. The IAE antioxidant activity was determined through the NBT reduction assay, deoxyrribose degradation and lipid peroxidation inhibition. The IAE showed to be effective in all assays, in a concentration-dependent manner (p < 0.01). In vasodilatation of endothelium-intact thoracic rat aorta rings, previously contracted with phenylephrine, the IAE caused a significant concentration-dependent effect (p < 0.01). In endothelium denuded aortic rings, the relaxation induced by the IAE occurred only at the highest tested concentrations. Pretreatment of the aortic rings with the NO synthase inhibitor, L-NOARG, and the endogenous substrate, L-arginine, confirmed the involvement of NO/GMPc pathway in the endothelium-dependent relaxation. The effect of ingesting IAE on ex vivo vascular reactivity was tested in LDL receptor knockout mice (LDLR KO) administered with 3 different doses of IAE. Animals were distributed in 5 groups (n = 7 per group): 1) control (C), normal chow and water ad libitum; 2) hypercholesterolemic (HC), cholesterol-rich diet (1.25 % of cholesterol) and water ad libitum; 3), 4), and 5) hypercholesterolemic-Ilex paraguariensis (HI), cholesterol-rich diet and IAE at the doses of 0.3; 0.9 and 2.7 g/kg/day, respectively. After a three-months treatment, HC mice showed serum total cholesterol, LDL-c plus VLDL-c values significantly elevated (p < 0.001). The IAE administration did not change the lipid profile of IAE-administered mices. HC mice aortic artery exhibited fatty streaks and showed a significant inhibition in response to phenylephrine contraction and to acethylcoline vasodilatation (p < 0.001). The IAE treatment reverted the reduction of contractile capacity in mice aorta in HI 0.9 and HI 2.7 groups and the inhibition of relaxation in HI 0.9 group (p < 0.05). In summary, the results showed that the commercial IAE have antioxidant and endothelial NO-dependent vasorelaxant properties in vitro. Furthermore, IAE ingestion improved ex vivo vascular reactivity of atherosclerotic LDLR KO mice aorta, regardless hypercholesterolaemia. Our results suggest that "mate" aqueous extract can be beneficial against atherosclerosis development.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-graduação em Farmacologia. A [SF63], obtida das cascas da [Croton Celtidifolius] administrada por via intraperitoneal, provocou antinocicepção quando avaliada nos modelos de contorção abdominal induzida pelo [Ácido acético], no teste da nocicepção induzida pela [Formalina], no teste da [Capsaicina], no teste [Glutamato], no teste da [Retirada da cauda] e no modelo da [Placa quente], em doses que não promoveram reações inespecíficas, como sedação e relaxamento muscular, avaliadas pelo teste do [Rota-rod]. Também foi observado que a [SF63] administrada por via oral apresenta atividade antinociceptiva, quando avaliada no teste da nocicepção induzida pela formalina. Os resultados sugerem que a [SF63]

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-Graduação em Farmacologia.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas O tratamento in vivo em camundongos com ligantes do receptor periférico benzodiazepínico (PBR) exerceram efeito inibitório na resposta inflamatória em dois modelos de inflamação aguda. No primeiro modelo o efeito antiinflamatório em de pré-tratamento com os ligantes PBR, PK11195 1-(2-chlorophenyl)-N-methyl-N(1-methylpropyl)-3-isoquinoline carboxamide e Ro5-4864 7-chloro-5-(4-Chlorophenyl)-1,3-dihydro-1-methyl-2-H-1,4-benzodiazepin-2, mostraram que a formação do edema em resposta a carragenina (300 mg/pata) foi inibida por PK11195 e Ro5-4864, em diferentes intervalos de tempo. O estudo do tempo resposta mostrou que a melhor resposta com ambos ligantes foi ótima em animais injetados no tempo de 24h, por esta razão este tempo de pré-tratamento foi escolhido para estudo da dose resposta. A formação do edema de pata em resposta a carragenina (300 mg/pata) foi reduzida por PK11195 e Ro5-4864 em diferentes doses (0,00001-10mg/kg, i.p.) produzindo uma inibição dose dependente na formação do edema de pata em camundongos induzida pela carragenina. PK11195 e Ro5-4864 (0.1 mg/kg, i.p.) quando administrado 24 h antes da indução do edema, inibiram de forma significativa o edema de pata de camundongos induzido por vários mediadores inflamatórios. No segundo modelo o pré-tratamento com os ligantes (0.1 mg/kg, i.p.), 24 h antes da indução da pleurisia induzida pela carragenina, mostrou uma significante inibição no recrutamento das células totais e diferenciais, principalmente a custas de neutrófilos, inibindo também a liberação de Interleucina-13 (IL-13) e Interleucina-6 (IL-6) no líquido pleural

Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas.