In vitro tissue culture, preliminar phytochemical analysis, and antibacterial activity of Psittacanthus linearis (Killip) J.K. Macbride (Loranthaceae) / Cultivo de tejidos in vitro, análisis fitoquímico preliminar y actividad antibacteriana de Psittacanthus linearis (Killip) J.K. Macbride (Loranthaceae)

ABSTRACT Hemiparasitic plants commonly known as mistletoe (muérdago in Spanish) in the families Santalaceae and Loranthaceae are common in various kinds of plants or trees, and many hemiparasitic plants are used for medicinal purposes in various parts of the world. The objective of the present work, carried out in Psittacanthus linearis (suelda con suelda), a representative species in the seasonally dry forest (SDF) from the north of Perú, was to study aspects of in vitro tissue culture, carry out preliminary phytochemical analysis, and assess antibacterial activity. Seeds of individuals of P. linearis, which used Prosopis pallida (algarrobo) as host plant, were collected and used to induce in vitro seed germination, clonal propagation, callus induction and organogenesis. Stems, leaves and fruits of individuals of P. linearis were dried, powdered, and subjected to ethanol extraction. Posteriorly the extract was first recovered with ethanol and the remnant with chloroform, which formed the ethanolic and chloroformic fraction. A preliminary phytochemical screening was performed and preliminary antibacterial studies with Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were carried out and their results are discussed. This is the first report about in vitro tissue culture, phytochemical analysis and antibacterial activity of P. linearis. The results may have important implications for understanding physiological and biochemical interactions between host and hemiparasitic species as well as P. linearis with P. pallida and other SDF species.

RESUMEN Las plantas hemiparásitas o 'mistletoe' o 'muérdago' son comunes en varios grupos vegetales o árboles, perteneciendo a las familias Santalaceae and Loranthaceae y muchas plantas hemiparásitas son usadas como medicina en varios lugares del mundo. El objetivo del presente trabajo realizado en Psittacanthus linearis or 'suelda con suelda', especie representativa en el bosque estacionalmente seco (BES) del norte del Perú, fue estudiar algunos aspectos en el cultivo de tejidos in vitro, el análisis fitoquímico preliminar y su actividad antibacterial. Semillas de P. linearis teniendo a Prosopis pallida 'algarrobo' como hospedero, fueron colectadas y utilizadas en la germinación in vitro, propagación clonal, inducción de callos y procesos organogénicos. Tallos, hojas y frutos de plantas silvestres fueron secados, pulverizados y sometidos a extracción con etanol y el extracto fue recuperado primero con etanol y el remanente con cloroformo formando las fraciones etanólica y clorofórmica. Se realizó un estudio fitoquímico y antibacteriano preliminar utilizando Staphylococcus aureus, Escherichia coli y Pseudomonas aeruginosa y los resultados son discutidos. Este trabajo es el primer estudio sobre cultivo de tejidos, análisis fitoquímico y actividad antibacteriana de P. linearis. Los resultados obtenidos tienen importantes implicancias para el conocimiento de las interacciones fisiológicas y bioquímicas entre las especies hospederas y las plantas hemiparásitas, como P. linearis con P. pallida y otras especies del BES.

Influence of green tea extract with different concentrations of epigallocatechin gallate on calvaria bone repair of ovariectomized rats / Influencia del extracto de té verde con diferentes concentraciones de galato de epigalocatequina sobre la reparación ósea de calvaria de ratas ovariectomizadas

Impairing osteoporosis progression is a challenge, and recently the role of antioxidants has been associated to bone metabolism. Green tea extract is rich in catechins, especially epigallocatechin gallate (EGCG), which may help control osteoporosis damage in bone tissue. This investigation evaluated the efficacy of green tea ingestion containing different concentrations of EGCG in calvaria bone repair of ovariectomized rats. Wistar rats (n=15) were ovariectomized and divided into 3 groups: ovariectomized (OVX), ovariectomized + GTE 15 % EGCG (OVX/GTE15), and ovariectomized + GTE 94 % EGCG (OVX/GTE94). Green tea extract was administered by gavage in the concentration of 50 mg/kg and sham group (n=5) received water. Bone defects were performed in the calvaria 60 days after ovariectomy followed by 4 weeks until euthanasia. Bone samples were collected to perform qualitative and quantitative histological analysis of bone formation. Data obtained were submitted to normality and ANOVA statistical test for p<0.05. The mean values of neoformed bone for Sham, OVX, OVX/GTE15 and OVX/GTE94 were respectively: 21.11 ± 3.91; 19.92 ± 2.20; 33.05 ± 1.26 e 34.75 ± 0.54 (p<0.05). Results show that continuous ingestion of green tea extract immediately after ovariectomy shows positive effects in the prevention of bone loss in osteoporosis, even with low concentrations of EGCG.

La disminución en la progresión de la osteoporosis es un desafío, y recientemente el papel de los antioxidantes se ha asociado al metabolismo óseo. El extracto de té verde es rico en catequinas, especialmente el galato de epigalocatequina (EGCG), lo que puede ayudar a controlar el daño de la osteoporosis en el tejido óseo. Esta investigación evaluó la eficacia de la ingesta de té verde con diferentes concentraciones de EGCG en la reparación ósea de calvaria de ratas ovariectomizadas. Las ratas Wistar (n = 15) fueron ovariectomizadas y divididas en 3 grupos: ovariectomizadas (OVX), ovariectomizadas + GTE 15 % EGCG (OVX / GTE15), y ovariectomizadas + GTE 94 % EGCG (OVX / GTE94). El extracto de té verde se administró por sonda en una concentración de 50 mg/kg y el grupo simulado (n = 5) recibió agua. Los defectos óseos se realizaron en la calvaria 60 días después de la ovariectomía, seguido de 4 semanas hasta la eutanasia. Se obtuvieron muestras de hueso para realizar un análisis histológico cualitativo y cuantitativo de la formación ósea. Los datos obtenidos se sometieron a normalidad y prueba estadística ANOVA (p<0,05). Los valores medios de hueso neoformado para Sham, OVX, OVX / GTE15 y OVX / GTE94 fueron: 21,11 ± 3,91; 19,92 ± 2,20; 33,05 ± 1,26 y 34,75 ± 0,54 (p <0,05), respectivamente. Los resultados muestran que la ingesta continua de extracto de té verde, inmediatamente después de la ovariectomía, muestra efectos positivos en la prevención de la pérdida ósea ocurrida en la osteoporosis, incluso con concentraciones bajas de EGCG.

Green tea supplementation improves oxidative stress biomarkers and modulates IL-6 circulating levels in obese women.

INTRODUCTION: Introduction: obesity is associated with high levels of oxidative stress (OS) and inflammation. There is a lot of evidence that some polyphenols, such as green tea, have a positive impact on the OS state and consecutively, on inflammation. Objectives: the purposes of this study were: a) evaluate OS biomarkers in both obese and normal weight women; and b) evaluate if green tea supplementation has an impact on OS and inflammatory cytokine biomarkers of obese women. Methods: we evaluated obese (body mass index [BMI] ≥ 40 kg/m²) and normal weight (BMI between 18.5 and 24.9 kg/m²) women. Blood samples were used to access malondialdehyde (MDA), trolox equivalent antioxidant capacity (TEAC) and inflammatory cytokines. We randomly chose obese patients (18 individuals) and then gave them green tea supplementation for eight weeks. Statistical analysis included the Shapiro-Wilk, Wilcoxon, independent and paired t tests; p < 0.05 were considered as significant. Results: we enrolled 42 obese (BMI: 48.2 ± 9.3kg/m2) and 21 normal weight (BMI: 22.5 ± 2 kg/m2) women with an average age of 36.2 ± 9.1 years old. The serum levels of MDA were higher in obese (2.52 ± 0.31 µmol/l) than in eutrophic women (2.13 ± 0.26 µmol/l; p = 0.000). On the other hand, lower TEAC values were observed in the obese (0.75 ± 0.06 mM/l) than in the eutrophic group (0.78 ± 0.04 mM/l; p = 0.009). After the green tea intervention, MDA decreased 4.7% and TEAC increased 10%. Interleukin-6 (IL-6) serum levels decreased 12.7% after treatment (p = 0.03). Conclusions: a) the obese group had lower antioxidant capacity than eutrophic; and b) green tea supplementation ameliorated TEAC and MDA and reduced serum levels of IL-6 in obese women.

INTRODUCCIÓN: Introducción: la obesidad se asocia con altos niveles de estrés oxidativo (EO) e inflamación. Existe mucha evidencia de que algunos polifenoles, como el té verde, tienen un impacto positivo en el estado del EO y, consecutivamente, en la inflamación. Objetivos: los propósitos de este estudio fueron: a) evaluar los biomarcadores de EO en mujeres obesas y de peso normal; y b) evaluar si la suplementación con té verde tiene un impacto en el EO y biomarcadores de citoquinas inflamatorias de las mujeres obesas. Métodos: evaluamos mujeres obesas (índice de masa corporal [IMC] ≥ 40 kg/m²) y con peso normal (IMC entre 18,5 y 24,9 kg/m²). Se utilizaron muestras de sangre para determinar el malondialdehído (MDA), la capacidad antioxidante equivalente de trolox (TEAC) y las citoquinas inflamatorias. Elegimos al azar pacientes obesas (18 individuos) y luego les dimos suplementos de té verde durante ocho semanas. El análisis estadístico incluyó las pruebas de Shapiro-Wilk, Wilcoxon, t pareadas e independientes; p < 0,05 fueron considerados como significativos. Resultados: se reclutaron 42 mujeres obesas (IMC: 48,2 ± 9,3 kg/m2) y 21 de peso normal (IMC: 22,5 ± 2 kg/m2) con un promedio de edad de 36,2 ± 9,1 años. Los niveles séricos de MDA fueron más altos en las personas obesas (2,52 ± 0,31 µmol/L) que en las mujeres eutróficas (2,13 ± 0,26 µmol/L; p = 0,000). Por otro lado, se observaron valores TEAC más bajos en los obesos (0,75 ± 0,06 mM/L) que en el grupo eutrófico (0,78 ± 0,04 mM/L; p = 0,009). Después de la intervención con té verde, la MDA disminuyó 4.7% y el TEAC aumentó 10%. Los niveles séricos de interleucina-6 (IL-6) disminuyeron 12.7% después del tratamiento (p = 0,03). Conclusiones: a) mujeres obesas tienen menor capacidad antioxidante que las eutrófica; y b) la suplementación con té verde mejora TEAC y MDA y redujo los niveles séricos de IL-6 en mujeres obesas.

Influência de inibidores de proteases no potencial de degradação do colágeno proveniente da dentina sadia, esclerótica e afetada por cárie / Influence of protease inhibitors on the degradation potential of collagen from sound, sclerotic and caries-affected dentin

Objetivo: Avaliar a influência de inibidores de proteases no potencial de degradação do colágeno das dentina sadia, esclerótica e afetada por cárie. Materiais e métodos: Trinta e nove molares humanos foram utilizados, treze para cada condição dentinária. Três fatias foram obtidas de cada dente, cada uma imersa em diferentes soluções: 1) saliva artificial; 2) clorexidina 2%; 3) EGCG 0,5%. Após incubação nas soluções por 1h, amostras foram sujeitas à degradação enzimática pela colagenase derivada da Clostridium histolyticum. Propriedades mecânicas de nanodureza (HIT) e módulo de elasticidade (Er) dos três diferentes tipos de dentina foram mensuradas antes e após a degradação, bem como a resistência à tração do colágeno. Resultados do teste de resistência à tração e nanoindentação foram submetidos à ANOVA dois e três fatores para medidas repetidas, e pós-teste de Tukey (α=0,05). Resultados: Maiores valores de resistência à tração foram encontrados para dentina sadia, nos grupos controle (40,30 ± 21,38 MPa) e EGCG 0,5% (30,05 ± 19,67 MPa). Antes da degradação, maiores valores de HIT (0,237 ± 0,062 GPa) e Er (5,58 ± 1,75 GPa) foram encontrados para o grupo EGCG 0,5%, na dentina afetada por cárie. Após a degradação, grupo clorexidina 2% apresentou maiores valores de HIT e Er para dentinas sadia (0,134 ± 0,020 GPa e 3,57 ± 0,40 GPa) e esclerótica (0,201 ± 0,048 GPa e 4,30 ± 0,56 GPa). Conclusões: O uso da clorexidina 2%, principalmente em dentina esclerótica, mostrou-se mais efetivo em promover aumento na resistência à tração e nas propriedades mecânicas, antes e após a degradação. A EGCG 0,5% apresentou melhor efeito sobre as propriedades mecânicas na dentina afetada por cárie, especialmente antes da degradação enzimática. Relevância Clínica: O efetivo conhecimento do mecanismo de ação de inibidores de proteases em diferentes tipos de dentina poderia contribuir para melhoria da resistência do substrato e para maior longevidade dos processos de união sobre este tecido(AU)

Objetive: To evaluate the influence of proteases inhibitors on the collagen degradation from sound, sclerotic and caries-affected dentin. Materials and Methods: Thirty-nine human molars were used, thirteen for each dentin condition. Three slices were obtained from each tooth, each one immersed in different solutions: 1) artificial saliva; 2) 2% chlorhexidine; 3) 0.5% EGCG. After incubation in the solutions for 1h, samples were subjected to enzymatic degradation by collagenase derived from Clostridium histolyticum. Mechanical properties of nanohardness (HIT) and elastic modulus (Er) of the three types of dentin were measured before and after degradation, as well as the microtensile strength. Results of the microtensile strength and nanoindentation tests were submitted to ANOVA two and three factors for repeated measurements, and Tukey post-test (α = 0.05). Results: Higher values of tensile strength were found for sound dentin in control (40.30 ± 21.38 MPa) and 0.5% EGCG (30.05 ± 19.67 MPa) groups. Before degradation, higher values of HIT (0.237 ± 0.062 GPa) and Er (5.58 ± 1.75 GPa) were found for the 0.5% EGCG group in caries-affected dentin. After degradation, 2% chlorhexidine group had higher values of HIT and Er for sound (0.134 ± 0.020 GPa and 3.57 ± 0.40 GPa) and sclerotic (0.201 ± 0.048 GPa and 4.30 ± 0.56 GPa) dentin. Conclusions: The use of 2% chlorhexidine, mainly in sclerotic dentin, was shown to be more effective in promoting increase in the microtensile strength and mechanical properties, before and after the degradation. The 0.5% EGCG showed a better effect on mechanical properties in caries-affected dentin, before the enzymatic degradation. Clinical Relevance: The effective knowledge of the mechanism of action of protease inhibitors in different types of dentin could contribute to the improvement of the resistance of the substrate and to the longer longevity of the bonding processes on this tissue(AU)

Characterization of the most promising fraction of Swietenia macrophylla active against myotoxic phospholipases A2: identification of catechin as one of the active compounds / Caracterización de la fracción más promisoria de Swietenia macrophylla activa contra fosfolipasas A2 miotoxicas: identificación de catequina como uno de los compuestos activos

Background: The pharmacological effects produced by snakebite accidents involve the actions of several enzymes, of which those of the phospholipases A2 (PLA2) exhibit a wide variety of effects such as edema and myotoxicity. Some plant extracts have been antagonists of crude snake venoms and toxins. Based on promising bioactivity, Swietenia macrophylla King was selected for further studies. Objective: The purpose of this study was to identify the PLA2 inhibitors present in the crude extract of S. macrophylla that could be promising leads in neutralizing the local effects of ophidian accidents. Methods: Bioassay-guided fractionation of the ethanolic extract of the leaves of S. macrophylla lead to the detection of (+)-catechin, characterized through gas chromatography coupled with mass spectrometry (GC-MS), and confirmed by HPLC. The PLA2 inhibitory activity was measured with the Dole method and a spectrophotometric assay with 4-Nitro-3 octanoyloxy-benzoic acid (4N3OBA). Cytotoxicity was done on C2C12 murine myoblast. Results: Fraction F5 and (+)-Catechin inhibited the PLA2 activity of B. asper venom, in a dosedependent way. In addition, (+) Catechin showed an inhibition level of 83.1 ± 3.1 % of the enzymati activity of one PLA2 purified from the venom of Crotalus durissus cumanensis using 4N3OBA as substrate. Also the ethanolic extract and fraction F5 showed inhibition of the cytotoxicity induced by the Bothrops atrox venom and their Lys 49 PLA2 (80 and 100% respectively). Molecular docking results suggested that OH from 4´ and 5' carbons of (+)-catechin could form hydrogen bonds with carboxylate moiety of residue Asp49, while OH from 5 could form a hydrogen bond with Asn 6. Additional Van der Waals interactions were also proposed. Conclusion: Swietenia macrophylla exhibited strong inhibitory activity against PLA2s enzymes. Catechin, one of the components in the active fraction F5, is proposed as being partially responsible for the bioactivity.

Antecedentes: Los efectos farmacológicos producidos en el accidente ofídico implican la acción de varias enzimas, como las fosfolipasas A2 (PLA2), que exhiben una amplia variedad de efectos como edema y miotoxicidad. Algunos extractos de plantas han demostrado ser antagonistas de los venenos crudos y sus toxinas. En base a una bioactividad promisoria previa, Swietenia macrophylla King fue seleccionada para estudios posteriores. Objetivo: El propósito de este estudio fue identificar metabolitos inhibidores de PLA2 presentes en el extracto crudo de S. macrophylla que podrían ser prometedores en la neutralización de los efectos locales del accidente ofídico. Métodos: Un fraccionamiento biodirigido del extracto etanólico de hojas de S. macrophylla llevó a la detección de la (+)-catequina mediante cromatografía de gases acoplada a espectrometría de masas (GC-MS), y se confirmó mediante HPLC. La actividad inhibidora de PLA2 se determinó por el método de Dole y un ensayo espectrofotométrico con Ácido 4-Nitro-3-octanoiloxibenzoico (4N3OBA). La citotoxicidad se determinó en mioblastos C2C12 murinos. Resultados: La fracción F5 de S. macrophylla, mostró la mayor inhibición del veneno de Bothrops asper y PLA2s aisladas de B. atrox y Crotalus durissus cumanensis e inhibición completa de la citotoxicidad. La (+)-catequina fue el metabolito más abundante en F5, mostró una inhibición de PLA2 de 89,8%, 81,1% y 74,3%, a diferentes relaciones de veneno: catequina. Mediante estudios de docking molecular se demostró la unión de la (+)-catequina al sitio activo de la PLA2. Conclusión: Swietenia macrophylla exhibió una fuerte actividad inhibitoria sobre las enzimas PLA2s. La (+)-catequina, uno de los metabolitos presentes en la fracción activa F5, se propone como uno de los compuestos responsables de la bioactividad.

Efeito do antioxidante epigalocatequina-3-galato na perda óssea durante a periodontite induzida por ligadura em ratos: análise portomografia microcomputadorizada 2D e 3D e histomorfométrica / Effects of epigallocatechin-3-gallate antioxidant in bone loss during ligatureinducedperiodontitis in rats: analysis in 2D and 3D microcomputedtomography and histomorphometry

A doença periodontal é uma das doenças inflamatórias crônicas mais comuns queacometem a população. A grande destruição tecidual observada durante o seudesenvolvimento tem sido atribuída ao processo inflamatório exacerbado e aodesequilíbrio favorável à geração de espécies reativas de oxigênio em relação àcapacidade de defesa dos antioxidantes. A epigalocatequina-3-galato (EGCG) obtidada Camellia sinensis é uma substância que apresenta potencial antioxidante e antiinflamatórioe, mais recentemente, testes in vitro têm mostrado que também possuiatividade anti-osteoclastogênica, sendo apontada como uma possível droga parauso terapêutico nas patologias ósseas com excessiva atividade osteoclástica edestruição óssea. O objetivo do trabalho foi verificar morfométricamente em imagensobtidas pela tomografia microcomputadorizada (micro-CT) e cortes histológicos se aadministração diária de EGCG reduz o processo inflamatório e a perda ósseaalveolar na doença periodontal induzida por ligadura em ratos. O primeiro molarinferior direito de 60 ratos foi amarrado com fio de seda 3.0 e divididos em gruposem tratamento (GST), grupo tratado com EGCG (GTEGCG) que recebeudiariamente por gavagem 100mg/Kg de EGCG e grupo Sham (GTsalina) querecebeu apenas solução salina. Nos períodos de 0, 7, 14 e 21 dias (n=5animais/período/grupo) imagens digitais foram obtidas no microtomógrafo sendosubmetidos à análise do nível ósseo periodontal (PBL) e da densidade óssea(BV/TV) inter-radicular. Nos cortes longitudinais do M1 corados pela HE foi avaliadoo PBL e morfometricamente o percentual e volume de processo inflamatório e tecidoósseo, além do número osteoclastos/cm2. Os dados foram submetidos à ANOVA adois critérios e ao teste de Tukey (p<0,05). O PBL determinado nas imagensmicrotomográficas e histológicas mostraram que a perda óssea aumenta em todosos grupos durante a fase aguda da doença (0 a 14 dias) e estabiliza na fase crônica...

Periodontal disease is currently one of the most common chronic inflammatorydiseases affecting the population. The large tissue destruction observed during itsdevelopment, has been attributed to exacerbated inflammatory process andunbalance response between production of reactive oxygen species and antioxidantdefense capacity. Recently, the substance epigallocatechin-3-gallate (EGCG)obtained from Camellia sinensis have been associated to antioxidant and antiinflammatoryactions. In vitro studies have shown that EGCG has also antiosteoclastogenicactivity suggesting to be a potencial drug for use in therapeutictreatment of bone diseases with excessive osteoclast formation and bonedestruction. The aim of this study was to verify morphometrically in micro-ct andhistological images whether daily administration of EGCG inhibits/decreases alveolarbone loss in periodontal disease induced in rats by ligature. The lower right firstmolar of 60 rats was tied with surgical suture thread 3.0. The animals were dividedinto untreated group (GST), EGCG treated group (GTEGCG) which received100mg/kg of EGCG by gavage daily and Sham group (GT saline) which receivedsaline solution only. In periods of 0, 7, 14 and 21 days (n=5 animals/period/group)digital images were obtained in microtomography (SkyScan1176) and subjected toanalysis of PBL in the mesial, distal, buccal and lingual root and BV/TV bone volumepercentage. In the sagittal slides PBL volumetric points and inflammatory process aswell as the number of osteoclasts/cm2 was analyzed. Data were submitted to twowayANOVA and Tukey test (p <0.05). PBL determined in microtomographic andhistological images showed that bone loss increased and stabilized, respectively, inthe all groups acute phase (days 0 to 14) and chronic phase (14 days, 21 days) ofthe disease. In general, the PBL was lower in GTEGCG (average 0,839 mm)compared to GST and GTsaline (average 0,953). Regarding bone...

Efeito de resinas experimentais contendo inibidores de proteases da matriz sobre gelatinases e colagenases / Effect of experimental resins containing protease inhibitors on gelatinases and collagenase

A evolução das resinas compostas fez com que esses materiais passassem a ter uma durabilidade maior e características estéticas muito boas, mas o risco de cárie recorrente é ainda um problema a ser resolvido. Na tentativa de solucionar esse problema, estudos vêm sendo conduzidos na tentativa de se formularem resinas compostas contendo agentes antibacterianos, como é o caso da incorporação de clorexidina (CHX). Outro fato que impede a longevidade deste material é a degradação de matriz de colágeno por proteases ativadas por pH ácido. Para tentar contornar esse problema, a adição de clorexidina, assim como Epigallocatechin gallate (EGCg), clássicos antibacterianos e inibidores de proteases da matriz , como as metaloproteinases da matriz (MMP) a resinas, poderia melhorar a eficácia destes materiais como substitutos de dentina em procedimentos restauradores, aumentando a longevidade do tratamento restaurador, mediante preservação das propriedades mecânicas do material. Assim, o objetivo desse estudo é avaliar o poder de inibição de resinas experimentais contendo inibidores conhecidos de proteases da matriz sobre gelatinases e colagenase. Para isso, copolímeros experimentais foram preparados combinando Bis-GMA com o diluente TEGDMA (70/30 mol%). Com exceção do copolímero placebo (sem drogas), EGCg ou CHX foram incorporados a 1% em peso isoladamente ou em combinação, a 0,5% em peso cada. Amostras contendo EGCg, CHX ou EGCg e CHX concentradas 10X foram obtidas do armazenamento de espécimes polimerizados da resina experimental em água deionizada (1 mL) após o período de 24h a 37°C e sua posterior concentração. O efeito da ação dos inibidores foi checado por zimografia e confirmado por um ensaio enzimático específico para colagenases e gelatinases. Os dados passaram por teste de homogeneidade (Bartlett) e normalidade (Kolmogorov-Smirnov) e foram avaliados por ANOVA a 2 critérios, seguido pelo teste de Bonferroni para comparações individuais (p<0,05). Os resultados...

The evolution of composite resins made these materials to have a greater durability and very good esthetics characteristics, but the risk of recurrent caries is still a problem to be solved. In the attempt to solve this problem, studies are being conducted with the purpose to formulate composite resins containing antibacterial agents, such as chlorhexidine (CHX). Another fact that prevents the longevity of this material is the degradation of the collagen matrix by the proteases activated by acidic pH. In order to solve this problem, the addition of chlorhexidine and/or Epigallocatechin gallate (EGCg), classical antibacterial agents and inhibitors of matrix proteases, such as matrix metalloproteinases (MMP) in resins, could improve the efficacy of these materials as dentin substitutes in restorative procedures, increasing the longevity of the restorative treatment, while preserving the mechanical properties of the material. Thus, the aim of this study is to evaluate the ability of experimental resins containing known matrix protease inhibitors on the inhibition of gelatinases and collagenase. For this purpose, experimental copolymers were prepared combining Bis-GMA with the diluent TEGDMA (70/30 mol%). Except for the placebo copolymer (drug free), EGCg or CHX were incorporated at 1% in weight, isolated or in combination (0.5% in weight each). Samples containing EGCg, CHX or EGCg and CHX concentrated 10X were obtained after storage of polymerized specimens of the experimental resin in deionized water (1 mL) after the period of 24 h, at 37°C and after that were concentra. The effect of the action of the inhibitors was checked by zymography and confirmed by an enzymatic test specific for collagenases and gelatinases. The data passed in the tests of homogeneity (Bartlett test) and normality (Kolmogorov-Smirnov test), and were evaluated by 2-way ANOVA, followed by Bonferroni test for individual comparisons (p<0.05). The results of this study showed that the...

Growth inhibition of Walker carcinosarcoma 256 with alcoholic extract of green tea leaves (Camellia sinensis) / Inibição do crescimento do carcinossarcoma 256 de Walker pelo extrato alcoólico de folhas de chá verde(Camellia sinensis)

PURPOSE: To evaluate the antitumor activity of alcoholic extracts of green tea (Camella sinensis). METHODS: Four groups of six Wistar rats were inoculated intramuscularly with 10(6) Walker tumor cells/mL. During 10 days, the animals received by gavage either 0.9% saline solution (Group I; negative control), solution containing 20 mg/Kg of tamoxifen (Group II; positive control), solution containing 0.07 g/Kg alcoholic extract of C. sinensis (Group III), or solution containing 0.14 g/Kg alcoholic extract of C. sinensis (Group IV). Following euthanasia on the tenth day, the tumor, liver, kidneys and spleen were excised and weighed, and tumor volume and tumor growth inhibition were quantified. RESULTS: The average weight of the animals was greater in Group IV than in Group II (p=0.0107). Tumor weight was smaller in Group IV than in Group I (p=0.0062), but did not differ from Group II. Tumor volume was smaller in Groups II and IV than in Group I (p=0.0131). Tumor growth inhibition was observed in Groups II (44.67% ± 32.47), III (16.83% ± 53.02) and IV (66.4% ± 25.82) (p>0.05). The groups did not differ with regard to the weight of the excised organs. CONCLUSION: Alcoholic extracts of green tea have antitumor activity.

OBJETIVO: Avaliar a atividade antitumoral do extrato alcoólico do chá verde (C. sinensis). MÉTODOS: Quatro grupos de seis ratos Wistar foram inoculados com 1x10(6) células/mL do tumor de Walker por via intramuscular. Os grupos foram tratados durante 10 dias, por gavagem, com salina 0,9 % (Grupo I, controle negativo), 20 mg/Kg de tamoxifeno (Grupo II, controle positivo) e extrato alcoólico de C. sinensis nas doses de 0,07 g/Kg (Grupo III) ou 0,14 g/Kg (Grupo IV). O volume e a inibição do crescimento tumoral foram calculados. RESULTADOS: A média dos pesos dos animais foi maior no Grupo IV do que no Grupo II (p=0,0107). O peso tumoral do Grupo IV foi menor do que o Grupo I (p=0,0062), mas não houve diferença quando comparado ao Grupo II. O volume tumoral foi menor nos grupos II e IV quando comparados ao Grupo I (p=0,0131). Inibição tumoral foi observada nos Grupos II = 44,67 ± 32,47, III = 16,83 ± 53,02 e IV = 66,4 ± 25,82 (p>0,05). Não houve diferença no peso dos órgãos entre os grupos. CONCLUSÃO: O extrato alcoólico do chá verde possui ação antitumoral.

Protection of tooth structure by chlorhexidine and natural polyphenols: a review / Proteção da estrutura dental pela clorexidina e polifenóis naturais: revisão de literatura

Caries is a multifactorial and transmittable disease that results mainly from bacteria present in the oral cavity. Oral microorganisms can produce metabolic acids that diffuse through dental tissues and interfaces leading to dissolution of mineral. In dentine, after mineral is dissolved, organic matrix is also exposed to breakdown by host enzymes such as matrix metalloproteinases (MMPs) that are activated by low pH followed by neutralization. This review aims to discuss the activity of different antibacterial and antiproteolytic compounds such as chlorhexidine and natural polyphenols in the control of caries progression.

A cárie é uma doença transmissível e multifatorial, resultante principalmente da presença de bactérias na cavidade oral. Os microorganismos orais podem produzir metabólitos ácidos que se difundem entre os tecidos e interfaces dentais levando a dissolução de minerais. Na dentina, após dissolução mineral, a matriz orgânica também é sujeita à degradação por enzimas, como as metaloproteinases (MMPs), que são ativadas pelo baixo pH seguido de neutralização. Esta revisão objetiva discutir a atividade de diferentes compostos antibacterianos e antiproteolíticos, como clorexidina e polifenóis, no controle da progressão de lesões cariosas.

Determinação de taninos e metilxantinas no guaraná em pó (Paullinia cupana Kunth, Sapindaceae) por cromatografia líquida de alta eficiência / Determination of tannins and methylxanthines in powdered guarana (Paullinia cupana Kunth, Sapindaceae) by high performance liquid chromatography

As sementes de guaraná (Paullinia cupana Kunth, Sapindaceae) são utilizadas como estimulante e os principais constituintes químicos são as metilxantinas e os taninos, tais como catequina e epicatequina. Este trabalho teve por objetivo investigar um método por cromatografia líquida de alta eficiência (CLAE) para quantificar, simultaneamente, cafeína, teofilina, teobromina, catequina e epicatequina em pó de guaraná. Os valores obtidos foram comparados com os resultados encontrados no método espectrofotométrico da Farmacopéia Brasileira IV ed. Pelo método cromatográfico, os teores de metilxantinas e taninos totais foram de 4,04 por cento e 1,48 por cento, respectivamente. Os teores de metilxantinas e taninos totais, obtidos pelo método espectrofotométrico, foram de 4,88 por cento e 4,05 por cento, respectivamente. Acredita-se que, nas condições experimentais empregadas, o método espectrofotométrico não foi específico, quantificando outras substâncias fenólicas presentes no guaraná. Portanto, sugere-se o emprego desse método cromatográfico no controle de qualidade do guaraná em pó, por ser preciso, sensível, específico e rápido.

The seeds of Paullinia cupana Kunth, Sapindaceae, are used as a stimulant and the main chemical constituents are the methylxanthines and tannins, as catechin and epicatechin. This study aimed to investigate a method by high performance liquid chromatography (HPLC) to quantify both caffeine, theophylline, theobromine, catechin and epicatechin in powdered of P. cupana. The values obtained were compared with the results of the spectrophotometric method of the Brazilian Pharmacopoeia IV ed. For the chromatographic method, the levels of methylxanthines and total tannins were 4.04 percent and 1.48 percent, respectively. The levels of methylxanthines and total tannins obtained by the spectrophotometric method, were 4.88 percent and 4.05 percent, respectively. It is believed that, under our experimental conditions, the spectrophotometric method was not specific and quantified others phenolic substances present in the P. cupana. Therefore we suggest the use of this chromatographic method in quality control of P. cupana powder, to be accurate, sensitive, specific and fast.

Validación de la técnica para la determinación de catequina en tabletas de Rhizophora mangle L por CLAR / Validation of the technique to assessment of tablets Catechin from Rhizophora mangle L by HPLC

Se realizó la validación del método de cromatografía líquida de alta resolución para la determinación cuantitativa de catequina como sustancia marcador en las tabletas obtenidas a partir del extracto seco de las cortezas de Rhizophora mangle L, empleadas en el tratamiento de úlceras gastroduodenales. Considerando que el método se clasifica como tal para la determinación cuantitativa del compuesto mayoritario o ingrediente activo en formulaciones o materia prima, se evaluaron los parámetros: especificidad, linealidad, exactitud, sensibilidad y precisión expresada en sus 2 formas: repetibilidad y precisión intermedia. Los resultados obtenidos demostraron que el método empleado es confiable, pues permitió la determinación del compuesto en presencia de otras sustancias, incluyendo excipientes y sustancias auxiliares, y detectó la presencia de productos de degradación. Además, el procesamiento estadístico de los resultados evidenció la linealidad, precisión, sensibilidad y exactitud del método.

Authors made the high-performance liquid chromatography method validation to the quantitative assessment of cathechin as a marker substance in tablets obtained from the bark of Rhizophora mangle L dry extract used in gastroduodenal ulcers treatment. Considering that this method as such is classified to quantitative assessment of the major compound or active ingredient in formulae or raw material, the following parameters were assessed : linearity, accuracy, sensitivity and precision expressed in its two ways: repetition and intermediate precision. Results obtained showed that this method is reliable allowing the compound assessment in presence of other substances, including excipients and auxilliary substances and to detect the presence of degradation products. Also, the statistical processing of results evidenced the linearity, precision, sensitivity and accuracy of this method.

Validación de la técnica para la determinación de catequina en tabletas de Rhizophora mangle L por CLAR / Validation of the technique to assessment of tablets Catechin from Rhizophora mangle L by HPLC

Se realizó la validación del método de cromatografía líquida de alta resolución para la determinación cuantitativa de catequina como sustancia marcador en las tabletas obtenidas a partir del extracto seco de las cortezas de Rhizophora mangle L, empleadas en el tratamiento de úlceras gastroduodenales. Considerando que el método se clasifica como tal para la determinación cuantitativa del compuesto mayoritario o ingrediente activo en formulaciones o materia prima, se evaluaron los parámetros: especificidad, linealidad, exactitud, sensibilidad y precisión expresada en sus 2 formas: repetibilidad y precisión intermedia. Los resultados obtenidos demostraron que el método empleado es confiable, pues permitió la determinación del compuesto en presencia de otras sustancias, incluyendo excipientes y sustancias auxiliares, y detectó la presencia de productos de degradación. Además, el procesamiento estadístico de los resultados evidenció la linealidad, precisión, sensibilidad y exactitud del método(AU)

Authors made the high-performance liquid chromatography method validation to the quantitative assessment of cathechin as a marker substance in tablets obtained from the bark of Rhizophora mangle L dry extract used in gastroduodenal ulcers treatment. Considering that this method as such is classified to quantitative assessment of the major compound or active ingredient in formulae or raw material, the following parameters were assessed : linearity, accuracy, sensitivity and precision expressed in its two ways: repetition and intermediate precision. Results obtained showed that this method is reliable allowing the compound assessment in presence of other substances, including excipients and auxilliary substances and to detect the presence of degradation products. Also, the statistical processing of results evidenced the linearity, precision, sensitivity and accuracy of this method(AU)