Synthesis and evaluation of arylamidine derivatives for new antimicrobial and cytotoxic activities

ABSTRACT A series of arylamidines 3a-j was designed, synthesized and investigated for antimicrobial activity. Structures of the compounds were confirmed by IR, 1H-NMR and 13C-NMR and a 2D spectroscopic study was performed. A preliminary screening of the antimicrobial tests clearly showed that three out of ten arylamidines, viz, 3f, 3g and 3i, were effective against all the gram-negative bacteria: Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella enteric; and against the yeast, candida albicans. Further, the Minimum Inhibitory Concentrations (MIC) against the bacteria and yeast were determined. All compounds 3a-d, 3f, 3g, 3i and 3j were also investigated for their low cytotoxic effects on tested cell lines. Compounds 3d and 3f were the most effective derivatives against HL-60 and HEp-2 cells, respectively, with IC50 value (2µg/mL), and low normal cells toxicity.

Antioxidant properties of Ziziphus Jujuba Mill. Aqueous extract of and its preventive role on RBC hemolysis induced by AAPH

Background and Aim: Jujube [Ziziphus Jujuba Mill.] is one of the medicinal herbs with grows in dry and semi-dry areas in Iran; mainly in the South Khorasan province. The present study aimed at evaluating antioxidant and free radical scavenging capacity in different types of Jujuba

Materials and Methods: Four ecotypes of Jujubes were collected from different parts of the South Khorasan providence [Sarayan, Quaen, Arish, and Boshad]. The collected samples were air dried and then their aqueous extract was prepared in different dilutions. Anti-oxidant and free radical scavenging capacity of the samples were assessed using 2,2-diphenyl-1-picrylhydrazyl [DPPH] and Ferric Reducing Antioxidant Power [FRAP] methods. Their AAPH-induced hemolysis prevention was also analyzed. The total phenolic content of the samples was assessed using Folin-Ciocalteau method

Results: Maximum phenolic content was obtained from Quaen Jujube [1317+/-4.3 equal to mol Gallic acid]

The highest antioxidant capacity by FRAP [1390.1 +/- 65.5mol/L] also belonged to Quaen jujube. The ability of Arish Jujube extracts in scavenging and neutralizing free radical, tested by DPPH, was always higher compared to the other extracts. Results obtained from the effects of different dilutions of Jujube extracts [0- 25 - 5 mg/ml] on hemolysis showed a dose dependent relationship. All the extracts showed dose dependent reducing hemolysis in a specific range of concentrations, induced by 2,2'-azobis [2-amidinopropane] dihydrochloride [AAPH]. There was no significant statistical difference between jujube ecotypes in preventing hemolysis

Conclusion: According to total phenolic content of the Jujobe extracts, its significant antioxidant properties and radical scavenging activities, which was tested through different methods, it can be a potential booster for anti-oxidant capacities

Avaliação fenotípica in vitro de novas amidinas aromáticas sobre Trypanosoma cruzi / Phenotypic screening in vitro of novel aromatic amidines on trypanosoma cruzi

A doença de Chagas (DC), causada pelo protozoário Trypanosoma cruzi, é uma doença negligenciada endêmica em diferentes regiões empobrecidas da América Latina. O tratamento, baseado em dois nitroderivados, Nifurtimox e Benzonidazol(Bz), é insatisfatório, demandando a busca de novos fármacos com ação tripanocida que sejam mais seletivos e eficazes. Nesse âmbito, o presente trabalho busca a identificação de novos agentes antiparasitários para a DC, explorando a avaliação fenotípica de novas amidinas aromáticas sintéticas in vitro incluindo ensaios de combinação entre estes compostos. Dez novas amidinas foram testadas sobre tripomastigotas sanguíneos e amastigotas de diferentes cepas do T. cruzi (Y eTulahuen) e também sobre células de mamífero hospedeiras (linhagem L929 ecélulas cardíacas) para determinar seu perfil eficácia e de toxicidade,respectivamente. Dentre as moléculas testadas (apresentando um ou dois grupamentos catiônicos terminais), cinco foram mais ativas sobre tripomastigotas sanguíneos que o fármaco de referência (Bz), sendo uma delas, a DB2267(molécula dicatiônica) a mais eficaz, exibindo EC50 de 0,23 miM e um índice de seletividade (IS) de 417. Esta diamidina foi 28 vezes mais ativa e cerca de três vezes mais seletiva que Bz. Para determinar se a combinação de duas amidinas teria um efeito tripanocida superior ao seu uso em monoterapia, tripomastigotas sanguíneos foram incubados com DB2267 e DB2236 em proporções fixas e os resultados mostraram apenas um efeito aditivo com sigmaFIC<4. Interessantemente,quando formas intracelulares foram expostas à DB2267, sua atividade foi relacionada à cepa do parasito, sendo eficaz (EC50 = 0.87 ± 0.05 miM) contra DTU II(cepa Y), mas não contra um representante da DTU VI (Tulahuen), mesmo quando utilizamos veículo diferente do DMSO (beta-ciclodextrina)...

Chagas disease (CD), caused by the protozoan Trypanosoma cruzi, is a neglecteddisease endemic in different poor areas of Latin America. The treatment, based ontwo nitroderivatives, Nifurtimox and Benznidazole (Bz), is unsatisfactory, demandingthe screening of new potential trypanocidal drugs more selective and potent. In thisscope, the present work deals with the identification of new anti-parasitic agents forCD, exploring the phenotypic screening of novel synthetic aromatic amidines in vitroand also combination assays between these compounds. The novel ten amidineswere tested against bloodstream trypomastigotes (BT) and amastigote forms ofdifferent T.cruzi strains (Y and Tulahuen) and were also evaluated on mammalianhost cells (L929 cells and cardiac cells) to check their toxicity profile. Among thesemolecules, five were more active against BT than the reference drug (Bz), being oneof them, the DB2267 (a dicationic molecule) the most potent, exhibiting an EC50value of 0.23 µM and a selectivity index (SI) of 417. This diamidine was 28-fold moreactive and about 3 times more selective than Bz. To ascertain if the combination oftwo amidines could improve their trypanocidal activity, BT were incubated withDB2267 and DB2236 in fixed-ratio proportions and the data showed only an additiveeffect with sigmaFIC<4. Interestingly, when intracellular forms were exposed to DB2267,its activity was related to the parasite strain, being effective (EC50 = 0.87 ± 0.05 miM)against DTU II (Y strain) but not against one representative of DTU VI (Tulahuen)even using different vehicles (beta-cyclodextrins and DMSO)...

Apontamentos acerca da Cadeia do Ser e o lugar dos negros na filosofia natural na Europa setecentista / Notes on the Chain of Being and the place of blacks in eighteenth-century European natural philosophy

Por meio da análise de obras acadêmicas produzidas por filósofos naturais no século XVIII, pretendemos discutir algumas ideias recorrentes acerca da Grande Cadeia do Ser. Para tal, analisamos as relações entre filosofia e teologia natural no período. Reavaliamos ainda alguns elementos da Cadeia do Ser, investigando autores que discorreram sobre o tema em seus escritos. Por fim, elencamos um ponto específico das discussões setecentistas sobre a scala naturae, qual seja, as diversas e nem sempre convergentes ideias de que, a partir de características específicas, haveria diferenças entre os homens, bem como seu consequente lugar na Cadeia do Ser.

This examination of academic works produced by eighteenth-century natural philosophers discusses some recurring ideas about the Chain of Being. To this end, the article analyzes the relations between natural philosophy and theology during the period. It also re-evaluates some elements of the Chain of Being through an exploration of authors who addressed the topic in their writings. Lastly, it identifies a specific element within eighteenth-century discussions of scala naturae, to wit, the various and not always convergent ideas about whether there are differences between humans based on specific characteristics and, consequently, about the places they occupy in the chain of being.

Antioxidant effect of 4-nerolidylcatechol and -tocopherol in erythrocyte ghost membranes and phospholipid bilayers

4-Nerolidylcatechol (4-NC) is found in Pothomorphe umbellata root extracts and is reported to have a topical protective effect against UVB radiation-induced skin damage, toxicity in melanoma cell lines, and antimalarial activity. We report a comparative study of the antioxidant activity of 4-NC and α-tocopherol against lipid peroxidation initiated by two free radical-generating systems: 2,2′-azobis(2-aminopropane) hydrochloride (AAPH) and FeSO4/H2O2, in red blood cell ghost membranes and in egg phosphatidylcholine (PC) vesicles. Lipid peroxidation was monitored by membrane fluidity changes assessed by electron paramagnetic resonance spectroscopy of a spin-labeled lipid and by the formation of thiobarbituric acid-reactive substances. When lipoperoxidation was initiated by the hydroxyl radical in erythrocyte ghost membranes, both 4-NC and α-tocopherol acted in a very efficient manner. However, lower activities were observed when lipoperoxidation was initiated by the peroxyl radical; and, in this case, the protective effect of α-tocopherol was lower than that of 4-NC. In egg PC vesicles, malondialdehyde formation indicated that 4-NC was effective against lipoperoxidation initiated by both AAPH and FeSO4/H2O2, whereas α-tocopherol was less efficient in protecting against lipoperoxidation by AAPH, and behaved as a pro-oxidant for FeSO4/H2O2. The DPPH (2,2-diphenyl-1-picrylhydrazyl) free-radical assay indicated that two free radicals were scavenged per 4-NC molecule, and one free radical was scavenged per α-tocopherol molecule. These data provide new insights into the antioxidant capacity of 4-NC, which may have therapeutic applications for formulations designed to protect the skin from sunlight irradiation.

Laparoscopic Inguinal Hernia Repair: A Review of 1,000 Cases

PURPOSE: We reviewed our data compiled prospectively for evaluation of post-operative complications and recurrence of laparoscopic inguinal hernia repair. METHODS: Among the 1000 patients (age, > or =20 years old) who were undergone laparoscopic inguinal hernia surgery from January 2007 to July 2011, the age, sex, location, hernia type, operation time, postoperative morbidity, and conversion of 992 patients were analyzed. RESULTS: Among 992 patients, 919 (92.6%) were male and the mean age was 54.2 years (range, 20~90). Operation times (m inutes) for unilateral and bilateral hernia were 40.0 and 53.4, respectively. Mean operation time (minutes) showed a decrease over time, as that for the first half of all cases was 43.5 and that for the second half was 39.7 (p<0.001). Seven cases of conversion (post-radical prostatectomy hernia=7) were recorded to TAPP (n=3) or IPOM (n=4) from TEP. Eleven cases of postoperative catheterization (1.1%), five cases of port site seroma (0.5%), one case of mesh removal due to infection, 24 cases of seroma/hematoma (2.4%), 26 cases of neuralgia (2.6%), and four cases of bleeding with a drop in hemoglobin of more than 3 mg% (0.4%) were also recorded. There were three cases of recurrence (0.35%) at the median follow-up of 46 months (range, 20 to 70 months). CONCLUSION: Laparoscopic inguinal hernia repair can be performed safely, with low rates of complication and recurrence. This technique achieves good results combined with the benefits of minimally invasive surgery. We should be cautious in order to avoid postoperative bleeding, especially in cases of TEP.

Atividade de amidinas aromáticas sobre Trypanosoma cruzi: estudos in vitro e in vivo / Activity of aromatic amidines on Trypanosoma cruzi: in vitro and in vivo

O atual tratamento da doença de Chagas (DC) se baseia em dois compostos nitroderivados, o Nifurtimox (Nf) e benznidazol (Bz), ambos introduzidos na clínica médica há cerca de 40 anos e que têm sido considerados insatisfatórios principalmente devido à baixa atividade, sobretudo na fase crônica, além de alta toxicidade e, ou ocorrência de isolados do parasito resistentes a ambos nitroderivados. Assim como um dos principais desafios ainda a serem enfrentados há mais de cem anos depois da descoberta da DC diz respeito a identificação de novas terapias alternativas para o tratamento desta negligenciada parasitose, esta temática representou o principal objetivo da presente tese. Assim, estudos in vitro e in vivo foram conduzidos visando avaliar a eficácia de amidinas aromáticas, incluindo diamidinas e arilimidamidas (AIAs) sobre o T. cruzi, analisando ainda a localização e distribuição dos compostos aromáticos assim como seus alvos celulares. Nossos dados revelaram a ação tripanocida de diamidinas e AIAs sobre formas sanguíneas e amastigotas do parasito, e faixa micro e nanomolar, respectivamente. Alguns dos compostos estudados, em especial as AIAs DB745 e DB1831 exibiram excelente efeito sobre formas sanguíneas na presença de sangue a 4°C, demonstrando seu potencial uso também na profilaxia de bancos de sangue. De modo geral, as amidinas testadas, incluindo as AIAs, apresentaram superior eficácia que as drogas de referencia, incluindo o Bz e a violeta de genciana. AIAs como a DB745 foram ativas sobre diferentes cepas do T.cruzi, incluindo YuYu e Colombiana, que apresentam resistência natural a nitroderivados. Estudos ultra-estruturais e por ensaios fluorescentes (microscopia e citometria de fluxo) revelaram que o núcleo e a mitocôndria do parasito representam potenciais alvos dos compostos estudados. No entanto, não foi observada correlação entre atividade e maior acúmulo destes agentes na mitocôndria (kDNA) do T.cruzi. Os ensaios in vivo demonstraram que estes compostos aromáticos são ativos sobre modelos experimentais de infecção aguda pelo T.cruzi, reduzindo carga parasitária e a inflamação, oferecendo 100 porcento de proteção na mortalidade dos animais tratados. A AIA DB1965 revelou eficácia semelhante ao Bz e a sua combinação com esta droga de referência resultou em 100 porcento de sobrevida a níveis superiores a 99 porcento de supressão de parasitemia, sem alcançar cura parasitológica avaliada pelo hemocultivo e PCR. O excelente efeito de [amdinas], em especial de AIAs contra o T. cruzi, reforça o rastreamento por novos análogos que possam ser usados sozinhos ou em combinações com outras drogas, para o tratamento da doença de Chagas.

Protective effects of aqueous and ethanolic extracts of Nigella sativa L. and Portulaca oleracea L. on free radical induced hemolysis of RBCs

It has been shown that Nigella sativa L. and Portulaca oleracea L. have many antioxidant components. In the present study, the cytoprotective effect of ethanolic and aqueous extracts of N.sativa and P.oleracea against hemolytic damages induced by free radical initiator, AAPH [2, 2' azobis [2-amidinopropane] hydrochloride] was evaluated. Hemolysis was induced by addition of AAPH. To study the cytoprotective effect, aqueous [50, 200, 300, 400, 800 micro g/ml] and ethanolic [25, 100, 150, 200 and 400 micro g/ml] extracts of N. sativa and aqueous [25, 50, 100, 150, 200 and 400 micro g/ml] and ethanolic [300, 600, 900, 1200 and 1800 micro g/ml] extracts of P. oleracea were employed. RBCs were incubated with both extracts and AAPH at 37 °C for 6 hrs. In order to evaluate the impact of the time of addition, extracts were added one and 2 hrs after AAPH. Samples of suspensions were removed at different times and the degree of hemolysis was assessed spectrophotometrically by reading the absorption of supernatants at 540 nm. Aqueous [300, 400 and 800 micro g/ml] and ethanolic [150, 200 and 400 micro g/ml] extracts of N.sativa and also, aqueous [100, 150, 200 and 400 micro g/ml] and ethanolic [1200, 1800 micro g/ml] extracts of P.oleracea showed concentration-dependent cytoprotective effects. Addition of extracts one hour after AAPH reduced but did not eliminate protective activities of extracts. Cytorotective effect of aqueous and ethanolic extracts of N. sativa and P. oleracea against AAPH-induced hemolysis may be related to antioxidant properties of these plants

Hsp90 mediates activation of the heme regulated eIF-2 kinase during oxidative stress.

The heme-regulated inhibitor (HRI), a member of the eIF-2 kinase family is crucial for regulating protein synthesis during stress. In addition to heme, stress proteins Hsp90 and Hsp70 are known to regulate HRI. The present study aims to determine the physical association of these Hsps in the regulation of HRI activation during oxidative stress using human K562 cells as a model. Extracts from the stress-induced cells were used for determining HRI kinase activity by measuring eIF-2 phosphorylation, and Hsp-HRI interaction by immunoprecipitation and immunoblot analyses. The results indicate a significant increase in both Hsp70 and Hsp90 expression during AAPH (2, 2’-azobis (2-amidinopropane) dihydrochloride)-induced oxidative stress. Further, their interaction with HRI, which correlates well with its increased HRI kinase activity leads to inhibition of protein synthesis. Thus, we demonstrate that Hsps play an important role in the regulation of initiation of protein synthesis during oxidative stress.

1400W blocks death pathway of LPS-induced activated-microglia to preOLs / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To explore the efficacy of inductible nitric oxide synthase (iNOS) inhibitor 1400W in vivo in blocking the death pathway of lipopolysaccharide (LPS)-induced activated-microglia to preoligodendrocytes (preOLs) in neonatal rats with infective-type periventricular leukomalacia (PVL) induced by LPS.</p><p><b>METHODS</b>Two-day-old neonatal rats were randomly divided into: a sham-operated group, an untreated PVL group, and four 1400W-treated PVL groups that were subcutaneously administrated with 20 mg/kg of 1400W at 0 h, 8 hrs, 16 hrs, and 24 hrs after LPS induction, respectively. The brain specimens were obtained 5 days after LPS induction. The pathological assessment of cerebral white matter was performed under a light microscope. Concentrations of nitric oxide (NO) were measured by nitric acid-deoxidize colorimetry. Synthesis of iNOS was determined by Western blot analysis. Peroxynitrite (ONOO(-)) level and the amount of preOLs were determined by immunocytochemistry. RETHODS: The obvious injuries of periventricular white matter, massive loss of positive O4-labelled preOLs, and increased levels of NO, ONOO(-) and iNOS were observed in neonatal rats with PVL. Compared to the untreated PVL group, the use of 1400W at 0 h, 8 hrs and 16 hrs after LPS induction significantly improved white matter injuries, reduced the levels of NO, ONOO(-) and iNOS, and increased the amount of O4-labelled preOLs. However, the use of 1400W at 24 hrs after LPS induction did not result in the improvements.</p><p><b>CONCLUSIONS</b>iNOS inhibitor 1400W can effectively block the toxicity of LPS-activated microglia to preOLs and protect cerebral white matter through inhibiting iNOS and reducing the production of NO and ONOO(-). The use of 1400W within 16 hrs after LPS induction may provide cerebral protections in neonatal rats with PVL.</p>

AAPH scavenging activities of 22 flavonoids and phenolic acids and 9 extracts of Chinese materia medica / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the AAPH scavenging activities of 22 flavonoids and phenolic acids and 9 extracts of Chinese materia medica.</p><p><b>METHOD</b>The antioxidant activities of the samples were evaluated by an oxygen radical absorbance capacity method (ORAC), at the same time, the total contents of flavonoids and phenolic the 9 herb extracts were analyzed by Folin-Ciocalteu method, and the active components were qualitatively and quantitatively analyzed by an HPLC method.</p><p><b>RESULT</b>It was found that the tea extract showed the strongest AAPH activity with the ORAC value of 4786.40 micromol x g(-1) whereas safflower demonstrated the weakest activity with the ORAC value of 784.04 micromol x g(-1). As for compounds, quercetin had the strongest AAPH activity with the ORAC value of 12.90 while ( - )-EGC had the weakest activity with the ORAC value of 2.47. A quantitative relationship was obtained to describe the AAPH scavenging activity of the herb extracts: Y = 1844.8 lnX-3577.5, r = 0.8675, where Y stands for the ORAC vaule, and X stands for the concentration of total phenolic acids.</p><p><b>CONCLUSION</b>Flavonoids and phenolic acids are the AAPH scavenging active ingredients in the Chinese herb extracts. It's a good way to study the antioxidant activity of Chinese herb extract and its chemical composition by combing ORAC method and HPLC method.</p>

Effect of 1400W, an inhibitor of inducible nitric oxide synthetase, on blocking the toxicity of lipopolysaccharide-induced activated microglia to preoligodendrocytes / 中华儿科杂志

<p><b>OBJECTIVE</b>To explore the toxicity of LPS-induced activated microglia to preoligodendrocytes (preOLs) and the effect of 1400W, a selective inhibitor of inducible nitric oxide synthetase (iNOS), on the blockage of the toxicity.</p><p><b>METHODS</b>Co-cultured microglia and preOLs obtained from two-day-old Sprague-Dawley (SD) rats were divided into three groups: co-culture control group, co-culture LPS group and co-culture LPS plus 1400W group. After cultured cells were induced by LPS (100 ng/ml) for 48 hours, the concentration of nitric oxide (NO) was measured by nitric acid-oeoxidize-colorimetry, the level of peroxynitrite (ONOO(-)) was determined by immunocytochemistry, and the synthetic level of iNOS was detected by Western blotting, respectively. The morphologic observation of apoptotic preOLs stained with Hoechst 33342/PI and the apoptotic rate of preOLs detected by flow cytometry were processed simultaneously. Data were analyzed with SPSS 11.0 software.</p><p><b>RESULTS</b>Compared to co-culture control group, there was significant increase in levels of NO [(82.27+/-3.41) micromol/L vs. (167.86+/-9.87) micromol/L, t=8.593, P<0.01], ONOO(-)[(6.14+/-1.27) x 10(7)/L vs. (34.38+/-7.75) x 10(7)/L, t=5.892, P<0.01], and iNOS [(0.18+/-0.027) vs. (0.79+/-0.068), t=9.26, P<0.01] induced by LPS in co-culture LPS group, and with a higher apoptotic rate of preOLs [(6.73+/-1.39)% vs. (24.77+/-2.05)%, t=12.619, P<0.01]. However, all levels of NO [(69.55+/-5.07) micromol/L, t=8.896, P<0.01], ONOO(-) [(10.33+/-3.47) x 10(7)/L, t=14.96, P<0.01] and iNOS (0.35+/-0.042, t=5.506, P<0.01) decreased significantly with the use of 1400W at a dose of 10 micromol/L in co-culture LPS plus 1400W group, and the apoptotic rate of preOLs [(11.8+/-2.06)%, t=7.715, P<0.01] was also reduced evidently.</p><p><b>CONCLUSIONS</b>NO, ONOO(-) and iNOS, etc. play important roles in the death pathway of preOLs induced by LPS. 1400W can block effectively the toxicity of LPS-activated microglia toxicity to preOLs through inhibiting iNOS selectively and reducing the production of NO and ONOO(-), and improve the survival rate of preOLs.</p>

Design, synthesis and 5-HT/NE dual reuptake inhibitory activity of aromatic heterocyclic arylamidine derivatives / 药学学报

Based on the pharmacophore information and the analysis of structure-activity relationship of SSRIs and SNRIs, a series of substituted aromatic heterocyclic arylamidine derivatives were designed and synthesized in order to search for lead compounds with dual activity. All of them were new compounds, and their structures were confirmed by 1H NMR and HRMS. Preliminary in vitro pharmacological tests showed that all target compounds exhibited 5-HT reuptake inhibitory activity and some compounds exhibited NE reuptake inhibitory activity. These aromatic heterocyclic arylamidine designed can be further optimized for finding more potent 5-HT/NE dual reuptake inhibitors and antidepressant candidates as well.

Neurochemical Characterization of the TRPV1-Positive Nociceptive Primary Afferents Innervating Skeletal Muscles in the Rats

OBJECTIVE: Transient receptor potential vanilloid subfamily type 1 (TRPV1), a most specific marker of the nociceptive primary afferent, is expressed in peptidergic and non-pepetidergic primary afferents innervating skin and viscera. However, its expression in sensory fibers to skeletal muscle is not well known. In this study, we studied the neurochemical characteristics of TRPV1-positive primary afferents to skeletal muscles. METHODS: Sprague-Dawley rats were injected with total 20 microliter of 1% fast blue (FB) into the gastrocnemius and erector spinae muscle and animals were perfused 4 days after injection. FB-positive cells were traced in the L4-L5 (for gastrocnemius muscle) and L2-L4 (for erector spinae muscle) dorsal root ganglia. The neurochemical characteristics of the muscle afferents were studied with multiple immunofluorescence with TRPV1, calcitonin gene-related peptide (CGRP) and P2X(3). To identify spinal neurons responding to noxious stimulus to the skeletal muscle, 10% acetic acids were injected into the gastrocnemius and erector spinae muscles and expression of phospho extracellular signal-regulated kinase (pERK) in spinal cords were identified with immunohistochemical method. RESULTS: TRPV1 was expressed in about 49% of muscle afferents traced from gastrocnemius and 40% of erector spinae. Sixty-five to 60% of TRPV1-positive muscles afferents also expressed CGRP. In contrast, expression of P2X3 immnoreaction in TRPV1-positive muscle afferents were about 20%. TRPV1-positive primary afferents were contacted with spinal neurons expressing pERK after injection of acetic acid into the muscles. CONCLUSION: It is consequently suggested that nociception from skeletal muscles are mediated by TRPV1-positive primary afferents and majority of them are also peptidergic.

Effects of Ovariectomy and Calcium Intake on Lipid Profile and Antioxidant Capacities in Rats

The purpose of this research was to investigate the effect of the calcium intake on lipid profile and antioxidant capacities in ovariectomized (OVX) rats. Rats were divided into 3 groups and fed diet with different levels of calcium (low 0.1%, adequate 0.5%, high 1.5%) for 4 weeks. The half of rats in each group was ovariectomized and the others were sham-operated. And rats were fed same diets for 8 weeks after operation. Feed intake and weight gain were significantly higher in OVX group than those in sham-operated. Serum HDL-cholesterol was the highest in high-calcium group of OVX. Hepatic triglyceride of low-calcium group in sham-operated was the highest, while that of highcalcium group in OVX was the highest. Hepatic activities of glutathione-S-transferase (GST), glutathione peroxidase (GSH-Px), and catalase were significantly decreased by increasement of calcium intake. Hepatic TBARS level was the lowest in high-calcium group of OVX. And hepatic level of TBARS induced by AAPH was significantly decreased by increasement of calcium intake. These results may indicate that the high calcium intake have the potential role to improve lipid profiles and antioxidant capacities in OVX rats.

Effects of Green Tea on Weight Gain, Plasma and Liver Lipids and Lipid Peroxidation in Pair Fed Rats

We compared antiobese, hypocholesterolemic, antiplatelet and antioxidant effect of 10% green tea powder and 3% green tea extract in rats pair fed 5% cholesterol diets. The final body weight was decreased significantly compared with the control (p < 0.05). Plasma and liver total cholesterol were lower in group of green tea powder or extract, but not statistically different. HDL cholesterol was increased significantly in group of green tea powder compared with the control or green tea extract (p < 0.05). Plasma triglyceride was significantly decreased in group of green tea extract compared with green tea powder, and green tea powder compared with the control respectively (p < 0.05). Liver triglyceride was significantly decreased in group of green tea powder or green tea extract compared with the control (p < 0.01). Platelet aggregations in the maximum and initial slope were not different among groups. Hemolysis was significantly lower in group of green tea powder compared with the control (p < 0.05). Plasma TBARS production was decreased in group of green tea extract compared with the control (p < 0.05). Na passive leak in intact cells was not different, but Na leak in AAPH treated cell was significantly decreased in group of green tea powder than the control (p < 0.05). The leak increase (delta Na Leak) after AAPH treatment was significantly decreased in groups of green tea powder and extract compared with the control (p < 0.05). Isotope excretion after 14C-cholesterol ingestion was significantly increased in group of green tea extract compared with the control or the green tea powder (p < 0.05). Consumption of green tea in powder or extract may give beneficial effects in weight control and plasma lipid profiles, impeding metabolic syndrome. More studies are needed to clarify what component of green tea and what mechanism are involved in antiobese and hypolipedemic actions of green tea.

Free radical induced damages to rat liver subcellular organelles: inhibition by Andrographis paniculata extract.

Aqueous extract of Andrographis paniculata was examined for antioxidant activity using rat liver subcellular organelles as model systems. The study deals with two important biological oxidative agents, ascorbate-Fe(+2) and AAPH generating hydroxyl and peroxyl radical, respectively. Oxidative damage was examined against the inhibition of membrane peroxidation, protein oxidation and restoration in decreased SOD and catalase activity. The antimutagenic activity of Ap was examined following inhibition in AAPH induced strand breaks in plasmid pBR322 DNA. Extract was a potent scavenger of DPPH, ABTS radicals, exemplified by ESR signals, O2-*, *OH and H2O2, displayed excellent reducing power, FRAP potentials to reduce Fe (III) --> Fe (II) and had considerable amount of phenolics/ flavonoids contents, an effective antioxidant index. The observed antioxidant effect might be primarily due to its high scavenging ability for ROS. Effect was confirmed ex vivo following inhibition in peroxidation, restoration in SOD enzyme, SOD band intensity and protein degradation in Ap fed liver homogenate. Based on these results, it was concluded that the aqueous extract of Andrographis paniculata might emerge as a potent antiradical agent against various pathophysiological oxidants.

Atividade de amidinas reversas contra Trypanosoma cruzi in vitro / Activity of reversed amidines against Trypanosoma cruzi in vitro

A doença de Chagas, causada pelo protozoário Trypanosoma cruzi, é uma parasitose relevante e negligenciada afetando 16-18 milhões de indivíduos em áreas endêmicas da América Latina. A quimioterapia corrente, baseada em 2 nitroderivados (nifurtimox e benznidazol), é insatisfatória principalmente pela baixa atividade na fase crônica, alta toxicidade e devido ao aumento de isolados resistentes. Diamidinas aromáticas apresentam importante atividade anti-tumoral e antiparasitária, e vêem sendo utilizadas no tratamento de doenças parasitárias humanas e animais. Porém, devido à baixa biodisponibilidade oral e alta toxicidade, estudos têm sido desenvolvidos de modo a sintetizar e avaliar a ação de novos análogos dicatiônicos. Assim, a presente dissertação teve por objetivo caracterizar a atividade de amidinas reversas (ARs) contra Trypanosoma cruzi in vitro, comparando-a com a ação da diguanidina DB711. Nossos dados revelaram que ARs exibem importante efeito antiparasitário sobre amastigotas e tripomastigotas de T. cruzi em doses micro e nanomolares que não afetam a viabilidade de células de mamíferos. As amidinas DB889 e DB702 apresentaram superior atividade na maioria dos sistemas avaliados (diferentes formas evolutivas, diferentes condições de temperatura, e adição de sangue) em relação às duas outras ARs testadas, DB786 e DB811, sugerindo que pequenas varuações na estrutura química resultam em diferenças na potência antiparasitária. A análise das ARs sobre amastigotas não revelou diferenças no perfil de susceptibilidade entre os 2 estoques de T. cruzi testados, cepa Y e clone DM28c. Observamos superior atividade das ARs sobre tripomastigotas durante incubação a 37grausC, e que a adição de sangue reduziu a atividade tripanocida da maioria dos compostos testados à 4grausC, possivelmente devido à sua associação a componentes plasmáticos, como já relatado em outros estudos. Ensaios...A análise por microscopia eletrônica de transmissão (MET) revelou importantes altera...

Óxido nítrico sintase e proteínas quinase A como alvos de derivados amidínicos anti-Leishmania / Nitric oxide synthase and protein kinase A as the white of the amidínicos derivatives anti-Leishmania

Há muito tempo o tratamento das Leishmanioses tem feito uso de quimioterápicos utilizados em altas doses diárias que provocam diversas reações de toxicidade e o aparecimento de formas resistentes de Leishmania; tais fatores ressaltam a necessidade de estudos de drogas alternativas que possam permitir o desenvolvimento futuro de inibidores anti-leishmaniais. A abordagem moderna do desenvolvimento racional de drogas baseia-se na identificação de vias metabólicas indispensáveis à sobrevivência do microrganismo; desta forma, após a seleção de alvos biológicos, o objetivo passa a ser a caracterização detalhada de componentes de vias metabólicas envolvidas, e assim, enzimas-chave podem ser exploradas no desenvolvimento de inibidores de reações enzimáticas, sem afetar a célula hospedeira. Neste trabalho, duas importantes vias de sinalização foram avaliadas como alvos da quimioterapia experimental anti-Leishmania amazonensis utilizando uma N, NÆ-difenilbenzamidina metoxilada (metoxi-amidina): a) via do óxido nítrico (NO.) - aqui caracterizada pela detecção de nitrito em sobrenadante de culturas de promastigotas e amastigotas axênicas, imunofluorescência, cromatografia de afinidade, eletroforese de proteína, atividade de óxido nítrico sintase e inibição enzimática; e b) via da proteína quinase A (PKA), cuja atividade foi previamente caracterizada em Leishmania amazonensis e citada na literatura como participante na fosforilação da óxido nítrico sintase. Em comparação à droga de referência (Isetionato de Pentamidina), o derivado metoxilado diminuiu significativamente a produção de NO. e a atividade de PKA de promastigotas e amastigotas axênicas. Os resultados obtidos apontam a importância do NO. Como molécula sinalizadora na interação parasita-hospedeiro, e sua rota de biossíntese merece grande consideração em estudos da ação seletiva de quimioterápicos anti-Leishmania em doses toleradas pelostecidos do hospedeiro.

Ascorbate protects (+)-catechin from oxidation both in a pure chemical system and human plasma

We evaluated the interaction between ascorbic acid (AA) and (+)-catechin (CTCH) in potassium phosphate solution, pH 7.4 (PPS) and in human plasma. In both systems, the oxidation was started by adding 2,2'-azobis-(2-amidinopropane) clorhidrate (AAPH). The concentrations of AA and CTCH were determined by HPLC using electrochemical detection. In PPS, CTCH was oxidized by AAPH (50 mM), in either the absence or presence of different initial concentrations of AA (25-200 microM). In the presence of AA, CTCH depletion was delayed, an effect that was dependent upon the initial concentration of AA. When 100 microM AA was added after the oxidation had begun, CTCH depletion was arrested for 30 min. The kinetics of AA oxidation by AAPH was also characterized in PPS. AA (100 microM) was completely consumed after 60 min of reaction at 37 degrees C, in both the absence and presence of 100 mM CTCH. When human plasma was incubated with 50 mM AAPH in the absence of added CTCH, AA was completely consumed after 45-60 min. CTCH did not prevent AA depletion in human plasma at the concentrations tested (10, 50 100 microM). The results point out that AA is able to protect other aqueous soluble antioxidants, e.g.: CTCH.