Estudo comparativo de carragenanas comerciais Kappa, Iota e Lambda no processo inflamatório em ratos :edema intraplantar e pleurisia

The Iota, Kappa and Lambda commercial carrageenans are rarely pure and normally contain varying amounts of the other types of carrageenans. The exact amount of impurity depends on the seaweed source and extraction procedure. Then, different analysis methods have been applied for determination of the main constituents of carrageenans because these three carrageenans are extensively used in food, cosmetic and pharmaceutical industry. The electrophoresis of these compounds proved that the carrageenans are constituted by sulfated polysaccharides. These compounds were characterized by colorimetric methods and was observed that the Lambda carrageenan shown the greater value (33.38%) of sulfate. These polymers were examined by means of 13C NMR spectroscopy and infrared spectra. The polysaccharides consisted mainly of units alternating of sulfated galactoses and anhydrogalactoses. The aim of the study was also to test the inflammatory action of these different polysaccharides. A suitable model of inflammation is acute sterile inflammation of the rat hind limb induced by carrageenan. Paw edema was induced by injecting carrageenans (κ, ι and λ) in saline into the hind paw of a male Wistar rats (175–200 g). The pathway to acute inflammation by carrageenan (kappa, iota and lambda) were expressed as time-edema dependence and measured by paw edema volume. For this purpose, was used an apparatus (pakymeter), which makes it possible to measure the inflammation (swelling of the rat foot) with sufficient accuracy. The results showed that κ-carrageenan (1%) have an edema of 3.7 mm and the paw edema increase was time and dose dependent; the ι-carrageenan (0.2%) caused an edema of 4 mm and the λ-carrageenan (1%) caused an edema of 3.6 mm. Other model was used in this study based in the inflammation of pleura for comparatives studies. Injection of carrageenans into the pleural cavity of rat induced an acute inflammatory response characterized by fluid accumulation in the pleural cavity, a large number of neutrophils and raised NO production. The levels of NO were measured by Griess reactive. The ι-carrageenan caused the greater inflammation, because it has high concentration of nitrite/nitrate (63.478 nmoles/rat), exudato volume (1.52 ml) and PMNs (4902 x 103 cells). Quantitative evaluation of inflammations of rats is a useful and important parameter for the evaluation of the efficacy of anti-inflammatory drugs

Avaliação da atividade antimalárica de extratos obtidos de algas marinhas no litoral do Rio Grande do Norte

Malaria is a major parasitic disease worldwide, accounting for about 500 million cases and causing 2 million to 3 million deaths annually. Four species are responsible for transmitting this disease to humans: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae and Plasmodium ovale. The parasite resistance to antimalarial drugs and the usual limitations of the vector control implications are contributing to the spread of the disease. The most of significant advances in the search for new antimalarial drugs is based on natural components, the main ones being currently used antimalarial drugs derived from plants. Research on natural products of marine origin (particularly algae) show that some species possess antiplasmodial activity. Knowing that the coast of Rio Grande do Norte is home to several species of algae, the present study was to evaluate, for the first time, the antimalarial activity of ethanolic extracts of seaweed Spatoglossum schroederi, Gracilaria birdiae and Udotea flabellum against Plasmodium falciparum 3D7 strain tests and in vitro using the murine model (Plasmodium berghei) for evaluation in vivo. These species were ground, macerated with ethanol for 24 hours and the extracts concentrated in rotaevaporador (45 ° C ± 5 ° C). For in vitro tests, the extracts were diluted and tested at concentrations between 100 and 1.56 μg/ml (seven concentrations in triplicate), in order to obtain IC50 of each extract. The cytotoxicity tests with macrophages and BGM were performed using the MTT colorimetric assay. BGM macrophages and cells were distributed in 96 wells per plate (1x 105 to macrophages and 1x104 cells per well for BGM) and incubated for 24h at 37 ° C. The ethanol extracts were diluted and tested at concentrations of 100 to 1,56 μg/ml (seven concentrations in triplicate). After periods of 24 hours of incubation with the extracts, 100 μg of MTT was added to each well, and 3 hours elapsed, the supernatant was removed and added 200 μl of DMSO in each well. The absorbance of each well was obtained by reading on a spectrophotometer at 570 nm filter. To evaluate the acute toxicity in vivo, Swiss mice received a single dose (oral) 2000 mg/kg/animal of each extract tested. The parameters of acute toxicity were observed for 8 days. For in vivo tests, Swiss mice were inoculated with 1x105 erythrocytes infected with P. berghei. The treatment was given first to fourth day after infection with 0.2 ml of the extracts in doses of 1000 and 500 mg//g animal. The negative control group received 0.2 ml of 2% Tween-20, whereas the positive control group received sub-dose of chloroquine (5 mg/kg/animal). The assessment of antimalarial activity was done by suppressing suppressing the parasitemia at 5 and 7 days after infection. The growth inhibition of parasites was determined relative to negative control (% inhibition = parasitaemia in control - parasitemia in sample / parasitemia control x 100), the mortality of animals was monitored daily for 30 days The results showed that algae Spatoglossum schroederi and Udotea flabellum showed antimalarial activity in vitro, with reduced parasitemia of 70.54% and 54, respectively. The extracts of the three algae tested showed moderate to high cytotoxicity. Algae S. schroederi and U. flabellum were active against P. berghei only at doses of 500 mg / kg with reduction ranging from 54.58 to 52.65% for the fifth day and from 32.24 to 47.34% for the seventh day, respectively. No toxicity was observed in vivo at the dose tested, over the 8 days of observation. Although preliminary data, the bioactive components in those possible seaweed may be promising for the development of new anti-malarial drugs

Avaliação de efeitos biológicos de antiinflamatórios derivados do ácido propiônico através de modelos experimentais em nível molecular e celular

Derivatives of propionic acid NSAIDs are irreversible inhibitors of cyclooxygenase enzyme widely used. The aim of this study was to evaluate, through different experimental models, biological effects of derivatives of propionic acid (fenoprofen, naproxen, ibuprofen and ketoprofen) in cellular and molecular level. The labeling of blood constituents with technetium-99m (99mTc) and morphological analysis of erythrocytes of blood of rats, as well as growth, survival of cultures of Escherichia coli (E. coli) and the assessment of bacterial plasmid electrophoretic profiles were models used for experimental evaluation of possible biological effects of antiinflammatory drugs. The results show that, in general, anti-inflammatory drugs evaluated were not able to alter the labeling of blood constituents with 99mTc, the morphology of red blood cells from blood of rats, as well as the growth of cultures of E. coli and the electrophoretic profile of plasmid DNA. However, naproxen appears to cytotoxic effect on bacterial cultures, plasmids and genotoxic effects in reducing the action of stannous chloride in cultures of E. coli. The use of experimental fast performance and low cost was important for assessment of biological effects, contributing to a better understanding of the properties of propionic acid derivatives studied. anti-inflammatory, blood constituents, technetium-99m, stannous chloride, Escherichia coli; DNA

Structure and antimycobacterial activity of the novel organometallic [Pd(C-bzan)(SCN)(dppp)] compound

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pharmacological Evaluation and Preliminary Pharmacokinetics Studies of a New Diclofenac Prodrug without Gastric Ulceration Effect

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeito da complexação de metais aos antiinflamatórios na ação contra agentes oxidativos e radicais livres: ação do cetoprofeno

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Injúria renal aguda em unidade de terapia intensiva: estudo prospectivo sobre a incidência, fatores de risco e mortalidade

OBJETIVO: Comparar características clínicas e evolução de pacientes com e sem injúria renal aguda adquirida em unidade de terapia intensiva geral de um hospital universitário terciário e identificar fatores de risco associados ao desenvolvimento de injúria renal aguda e à mortalidade. MÉTODOS: Estudo prospectivo observacional com 564 pacientes acompanhados diariamente durante a internação em unidade de terapia intensiva geral do Hospital das Clínicas da Faculdade de Medicina de Botucatu por 2 anos consecutivos (de maio de 2008 a maio de 2010), divididos em 2 grupos: com injúria renal aguda adquirida (G1) e sem injúria renal aguda adquirida (G2). RESULTADOS: A incidência de injúria renal aguda foi 25,5%. Os grupos diferiram quanto à etiologia da admissão em unidade de terapia intensiva (sepse: G1:41,6% x G2:24,1%, p<0,0001 e pós operatório neurológico 13,8% x 38,1%, p<0,0001), idade (56,8±15,9 x 49,8± 17,8 anos, p< 0,0001), APACHE II (21,9±6,9 x 14,1±4,6, p<0,0001), ventilação mecânica (89,2 x 69,1%, p<0,0001) e uso de drogas vasoativas (78,3 x 56,1%, p<0,0001). Com relação aos fatores de risco e às comorbidades, os grupos foram diferentes quanto à presença de diabetes mellitus, insuficiência cardíaca congestiva, insuficiência renal crônica e uso de anti-inflamatórios não hormonais (28,2 x 19,7%, p=0,03; 23,6 x 11,6%, p=0,0002, 21,5 x 11,5%, p< 0,0001 e 23,5 x 7,1%, p<0,0001, respectivamente). O tempo de internação e a mortalidade foram superiores nos pacientes que adquiriram injúria renal aguda (6,6 ± 2,7 x 12,9± 5,6 dias p<0,0001 e 62,5 x 16,4%, p<0,0001). À análise multivariada foram identificados como fatores de risco para injúria renal aguda, idade>55 anos, APACHE II>16, creatinina (cr) basal>1,2 e uso de anti-inflamatórios não hormonais (OR=1,36 IC:1,22-1,85, OR=1,2 IC:1,11-1,33, OR=5,2 IC:2,3-11,6 e OR=2,15 IC:1,1-4,2, respectivamente) e a injúria renal aguda esteve independentemente associada ao maior tempo de internação e à mortalidade (OR=1,18 IC:1,05-1,26 e OR=1,24 IC:1,09-1,99 respectivamente). À análise da curva de sobrevida, após 30 dias de internação, a mortalidade foi de 83,3% no G1 e 45,2% no G2 (p<0,0001). CONCLUSÃO: A incidência de injúria renal aguda é elevada em unidade de terapia intensiva, os fatores de riscos independentes para adquirir injúria renal aguda são idade >55 anos, APACHE II>16, Cr basal >1,2 e uso de anti-inflamatórios não hormonais e a injúria renal aguda é fator de risco independente para o maior tempo de permanência em unidade de terapia intensiva e mortalidade.

DNA damage in lymphocytes and buccal mucosa cells of children with malignant tumours undergoing chemotherapy

The aim of the present study was to evaluate DNA damage (micronucleus) in cytokinesis-blocked lymphocytes and exfoliated buccal mucosa cells from children with malignant tumours and under chemotherapy. Micronucleated cells (MNCs) were assessed from children before and during chemotherapy. A total of 21 healthy children (controls), matched for gender and age, were used as control. The results pointed out higher frequencies of micronucleated lymphocytes in children with malignant tumour before any therapy when compared to healthy probands. Furthermore an increase of micronucleated lymphocytes during chemotherapy was detected when compared to the data obtained before chemotherapy. No statistically significant increases of MNCs were noticed in buccal mucosa cells at any of the timepoints evaluated. Taken together, these data indicate that the presence of malignant tumours may increase the frequency of DNA damage in circulating lymphocytes, these cells being more sensitive for detecting chromosome aberrations caused by anti-cancer drugs.

COX-2 Inhibitors for Cancer Treatment in Dogs

Cancer is one of the main causes of death in canines and felines, and this fact is probably related to the increase in the longevity of these species. The longer the animals live, the higher the exposure to carcinogenic agents will be. With the high incidence of cancer in companion animals, new studies are currently being performed with the aim of finding therapeutic options which make the complete inhibition of the development of neoplasms in animals possible in the future. The correlation of cyclooxygenase-2 (COX-2) whith the development of cancer opens the way for the use of new therapeutic approaches. This relationship has been suggested based on various studies which established an association between the chronic use of nonsteroidal anti-inflammatory drugs (NSAID) and a decrease in the incidence of colon carcinoma. As cancer progresses, COX-2 participates in the arachidonic acid metabolism by synthesizing prostaglandins which can mediate various mechanisms related to cancer development such as: increase in angiogenesis, inhibition of apoptosis, suppression of the immune response, acquisition of greater invasion capacity and metastasis. Accordingly, overexpression of this enzyme in tumors has been associated with the most aggressive, poor-prognosis cancer types, especially carcinomas. Therefore, treatments which use COX-2 inhibitors such as coxibs, whether administered as single agents or in combination with conventional antineoplastic chemotherapy, are an alternative for extending the survival of our cancer patients.

Activation of alpha(2)-adrenoceptors in the lateral hypothalamus reduces pilocarpine-induced salivation in rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Phospholipase A(2) myotoxins from Bothrops snake venoms: Structure-function relationship

Phospholipases A(2) constitute the major components from Bothrops snake venoms and have been extensively investigated not only because they are relatively very abundant in these venoms but mainly because they display a range of many relevant biological effects, including: myotoxic, cytotoxic, edema-inducing, artificial membrane disrupting, anticoagulant, neuromuscular, platelet aggregation inhibiting, hypotensive, bactericidal, anti-HIV, anti-tumoural, anti-malarial and anti-parasitic. The primary structures of several PLA(2)s have been elucidated through direct amino acid sequencing or, inderectly, through the corresponding nucleotide sequencing. Two main subgroups were thus described: (i) Asp49 PLA(2)s, showing low (basic, highly myotoxic) to relatively high (acidic, less or non myotoxic) Ca++-dependent hydrolytic activity upon artificial substrates; (ii) Lys49 PLA(2)s (basic, highly myotoxic) , showing no detectable hydrolytic activity on artificial substrates. Several crystal structures of Lys49 PLAs from genus Bothrops have already been solved, revealing very similar fold patterns. Lack of catalytic activity of myotoxic Lys49-PLA(2)s, first related solely with the fact that Lys49 occupies the position of the calcium ion in the catalyticly active site of Asp49 PLA(2)s, is now also attributed to Lys122 which interacts with the carbonyl of Cys29 hyperpolarising the peptide bond between Cys29 and Gly30 and trapping the fatty acid product in the active site, thus interrupting the catalytic cycle. This hypothesis, supported for three recent structures, is also discussed here. All Asp49 myotoxins showed to be pharmacologically more potent when compared with the Lys49 variants, but phospholipid hydrolysis is not an indispensable condition for the myotoxic, cytotoxic, bactericidal, anti-HIV, anti-parasitic, liposome disrupting or edema-inducing activities. Recent studies on site directed mutagenesis of the recombinant Lys49 myotoxin from Bothrops jararacussu revealed the participation of important amino acid residues in the membrane damaging and myotoxic activities.

Differences in gastroprotective and mutagenic actions between polar and apolar extracts of Ananas ananassoides

Several plants are used in folk medicine to treat gastrointestinal disorders. Ananas ananassoides (Baker) L. B. Smith (Family Bromeliaceae) is a medicinal plant commonly used in the central region of Brazil against gastric pain. We evaluated two extracts (methanol [MeOH] and dichloromethane [DCM]) obtained from the leaves of A. ananassoides for their ability to protect the gastric mucosa against injuries caused by necrotizing agents (0.3 M HCl/60% ethanol, absolute ethanol, non-steroidal anti-inflammatory drugs, and pylorus ligation) in mice and rats. The best results were obtained after pretreatment with the DCM extract, whereas the MeOH extract did not show any significant anti-ulcerogenic activity but presented mutagenic action. The mechanism of action of the DCM extract suggested the effective participation of endogenous sulfhydryl group in the gastroprotective action. The data, taken together with the absence of acute toxicity and mutagenicity, indicate the apolar extract, instead of the polar, extract of A. ananassoides as a safe and potential new anti-ulcerogenic drug.

LaRbp38: A Leishmania amazonensis protein that binds nuclear and kinetoplast DNAs

Leishmania amazonensis causes a wide spectrum of leishmaniasis. There are no vaccines or adequate treatment for leishmaniasis, therefore there is considerable interest in the identification of new targets for anti-leishmania drugs. The central role of telomere-binding proteins in cell maintenance makes these proteins potential targets for new drugs. In this work, we used a combination of purification chromatographies to screen L. amazonensis proteins for molecules capable of binding double-stranded telomeric DNA. This approach resulted in the purification of a 38 kDa polypeptide that was identified by mass spectrometry as Rbp38, a trypanosomatid protein previously shown to stabilize mitochondrial RNA and to associate with nuclear and kinetoplast DNAs. Western blotting and supershift assays confirmed the identity of the protein as LaRbp38. Competition and chromatin immunoprecipitation assays confirmed that LaRbp38 interacted with kinetoplast and nuclear DNAs in vivo and suggested that LaRbp38 may have dual cellular localization and more than one function. (C) 2007 Elsevier B.V. All rights reserved.

PRP8 intein in Ajellomycetaceae family pathogens: Sequence analysis, splicing evaluation and homing endonuclease activity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Shikimate Kinase (EC 2.7.1.71) from Mycobacterium tuberculosis: Kinetics and Structural Dynamics of a Potential Molecular Target for Drug Development

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)