The role of tannins as antiulcer agents: a fluorescence-imaging based study

Abstract Condensed tannins have been used for many years in folk medicine to treat gastric problems. The mechanism of action that explains why tannins improve gastritis symptoms is based on their ability to chelate metals, antioxidant activity, and their complexation power with other molecules. Even though these uses are well-known, the requirements to become an herbal medicine are much more complex. Herein, we analyzed Stryphnodendron rotundifolium Mart., Fabaceae, extract using MALDI for tannin characterization and carried out a fluorescence-imaging study to prove the gastroprotective effects of tannins as coating agents. Through these methods we show that condensed tannins form a gastroprotective layer. Moreover, we revise and discuss other possible mechanisms of action for phenolic-rich plant extracts and their potential in the development of herbal medicines to treat ulcers and gastritis.

New cascarosides from Rhamnus purshiana and fragmentation studies of the class by ion trap mass spectrometry.

RATIONALE: Anthrone and oxanthrone are important anthraquinone derivatives present in medicinal plants which are used in therapeutics as laxatives. Some of these plants need to be stored at least one year before they can be used in order to oxidize anthrones into oxanthrones, so to avoid severe diarrhea and dehydration. Therefore, this work aimed to characterize fragmentation reactions between these anthraquinones to provide an easy way to differentiate between the two classes, since it is necessary and important to discriminate and identify these derivatives in laxative plants and phytotherapic drugs. METHODS: Anthrone (cascarosides A-D) and oxanthrone (10-hydroxycascaroside A and B) derivatives were isolated and identified by NMR (1 H, 13 C, DEPT, NOESY) and used for fragmentation study by direct infusion on an electrospray ionization (ESI) ion trap mass spectrometer (AmazonSL, Bruker) in positive and negative mode. RESULTS: The additional hydroxyl at C-10 in oxanthrones allowed McLafferty-type rearrangements to form the quinone group in positive mode, while in negative mode the second sugar loss infringed the odd-electron rule and formed a radical fragment. No differences in fragmentation reactions were found between diastereoisomeric pairs, although the additional oxygen at C-10 of oxanthrones allowed a different fragmentation pattern. CONCLUSIONS: The proposed fragmentation patterns can be used to differentiate anthrones from oxanthrones in both ion modes. In addition, they can be applied to differentiate these compounds in anthraquinone-rich plants and phytotherapic drugs. Finally, herein, the strategy applied allowed us to identify new natural products. Copyright © 2017 John Wiley & Sons, Ltd.

Pharmacokinetic properties, in vitro metabolism and plasma protein binding of govaniadine an alkaloid isolated from Corydalis govaniana Wall.

Govaniadine (GOV) is an alkaloid isolated from Corydalis govaniana Wall. It has been reported to show a different number of biological activities including anti-urease, leishmanicidal and antinociceptive. The present study aims to characterize the GOV in vitro metabolism after incubation with rat and human liver microsomes (RLM and HLM, respectively) and to evaluate its pharmacokinetic properties. The identification of GOV metabolites was conducted by different mass analyzers: a micrOTOF II-ESI-ToF Bruker Daltonics® and an amaZon-SL ion trap (IT) Bruker Daltonics®. For the pharmacokinetic study of GOV in rats after intravenous administration, a LC-MS/MS method was developed and applied to. The analyses were performed using an Acquity UPLC® coupled to an Acquity TQD detector equipped with an ESI interface. The liver microsomal incubation resulted in new O-demethylated, di-hydroxylated and mono-hydroxylated compounds. Regarding the method validation, the calibration curve was linear over the concentration range of 2.5-3150.0ngmL-1, with a lower limit of quantitation (LLOQ) of 2.5ngmL-1. This method was successfully applied to a pharmacokinetic study. The profile was best fitted to a two-compartment model, the first phase with a high distribution rate constant (α) 0.139±0.086min-1, reflected by the short distribution half-life (t1/2α) 9.2±8.9min and the later one, with an elimination half-life (t1/2ß) 55.1±37.9min. The main plasma protein binding was 96.1%. This is a first report in this field and it will be useful for further development of govaniadine as a drug candidate.

Leishmanicidal evaluation of tetrahydroprotoberberine and spirocyclic erythrina-alkaloids.

Leishmaniasis is one of the World's most problematic diseases in developing countries. Traditional medicines to treat leishmaniasis have serious side effects, as well as significant parasite resistance problems. In this work, two alkaloids 1 and 2 were obtained from Corydalis govaniana Wall and seven alkaloids 3-9, were obtained from Erythrina verna. The structures of the compounds were confirmed by mass spectrometry and 1D- and 2D-NMR spectroscopy. The leishmanicidal activity of compounds 1-9 against Leishmania amazonensis was tested on promastigote forms and cytotoxicity against J774 (macrophage cell line) was assessed in vitro. Compound 1 showed potent activity (IC50 = 0.18 µg/mL), compared with the standard amphotericin B (IC50 = 0.20 µg/mL). The spirocyclic erythrina-alkaloids showed lower leishmanicidal activity than dibenzoquinolizine type alkaloids.

Estradiol transdérmico e perfil lipídico: efeitos em um grupo específico de mulheres brasileiras pós-menopausadas / Transdermal estradiol and lipid profile: effects on a specific group of brazilian postmenopausal women / Estradiol transdérmico y perfil lipídico: efectos en un grupo específico de mujeres brasileñas posmenopáusicas

Fundamento: Em mulheres pós-menopausadas, mudanças significantes ocorrem, que podem induzir doenças cardiovasculares, tais como o perfil lipídico aterogênico devido a um aumento nos níveis de colesterol total e LDL, e uma diminuição nos níveis de HDL. A terapia de reposição hormonal (TRH) pode evitar essas mudanças no perfil lipídico. Objetivo: Determinar os efeitos da TRH constituída por estradiol transdérmico e acetato de medroxiprogesterona nos parâmetros bioquímicos e lipídicos de mulheres brasileiras pós-menopausadas. Métodos: Este é um estudo prospectivo, longitudinal, aberto, no qual trinta mulheres pós-menopausadas receberam estradiol em gel transdérmico (1 mg/dia) de forma contínua, combinado com acetato de medroxiprogesterona (MPA) (5 mg/dia) por 12 dias/mês. Os seguintes parâmetros foram determinados: colesterol total, triglicérides, lipoproteína de alta densidade (HDL-colesterol), lipoproteína de baixa densidade (LDL-colesterol), lipoproteína de muito baixa densidade (VLDL-colesterol), glicose, aspartato aminotransferase (AST), alanina aminotransferase (ALT), gama-glutamil transferase (GGT) e hormônio folículo estimulante (FSH). Resultados: Os parâmetros do perfil lipídico mostraram uma diminuição não-significante, enquanto os níveis de GGT e FSH apresentaram uma diminuição estatisticamente significante. Conclusões: O tratamento com estradiol em gel transdérmico não mostrou um impacto significante no perfil lipídico, de forma que não resultou em um efeito benéfico nos marcadores de doenças cardiovasculares, sugerindo que a dose, modo de administração e o tempo de tratamento foram importantes para esses resultados. Além disso, o tratamento com dose baixa e modo de administração transdérmico também demonstrou um significante efeito hepático nessa população. Dessa forma, esse tratamento pode fornecer efeitos interessantes sobre o perfil lipídico em mulheres brasileiras pós-menopausadas.

Background: In postmenopausal women, significant changes occur that can induce cardiovascular diseases, such as atherogenic lipid profile, due to an increase in total cholesterol and LDL levels, and a decrease in HDL cholesterol levels. The hormone replacement therapy (HRT) can prevent these changes in lipid profile. Objective: Verify the effects of HRT consisting of transdermal estradiol gel associated with medroxyprogesterone acetate on the lipid profile and biochemical parameters in Brazilian postmenopausal women. Methods: This study is an open prospective longitudinal study, in which thirty postmenopausal women received transdermal estradiol gel (1 mg/day) continuously combined with oral medroxyprogesterone acetate (MPA) (5 mg/day) for 12 days/month. The following parameters were determined: total cholesterol, triglycerides, high density lipoprotein (HDL), low density lipoprotein (LDL), very low density lipoprotein (VLDL), glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gama glutamyl transferase (GGT) and follicle-stimulating hormone (FSH). Results: The parameters of the lipid profile did not show a significant decrease, while the levels of GGT and FSH had a statistically significant decrease. Conclusions: the treatment with transdermal estradiol gel did not have a significant impact on the lipid profile, thus not resulting in a beneficial effect on cardiovascular disease markers, suggesting that the dose, administration route and the time of treatment were important for these results. Moreover, the treatment using small dose and the transdermal administration route also had a significant hepatic effect in this population. Therefore, this treatment might provide interesting effects on the lipid profile in Brazilian postmenopausal women.

Fundamento: Cambios significantes ocurren en las mujeres posmenopáusicas que pueden inducir enfermedades cardiovasculares, tales como el perfil lipídico aterogénico debido a un aumento en los niveles de colesterol total y LDL y una disminución en los niveles de HDL. La terapia de reemplazo hormonal (TRH) puede evitar esos cambios en el perfil lipídico. Objetivo: Determinar los efectos de la TRH constituida por estradiol transdérmico y acetato de medroxiprogesterona en los parámetros bioquímicos y lipídicos de mujeres brasileñas posmenopáusicas Métodos: Este es un estudio prospectivo, longitudinal, abierto, en el que treinta mujeres posmenopáusicas recibieron estradiol en gel transdérmico (1 mg/día) de forma continua, combinado con acetato de medroxiprogesterona (MPA) (5 mg/día) por 12 días/mes. Se determinaron los seguientes parámetros: colesterol total, triglicéridos, lipoproteína de alta densidad (HDL-colesterol), lipoproteína de baja densidad (LDL-colesterol), lipoproteína de muy baja densidad (VLDL-colesterol), glucosa, aspartato transaminasa (AST), alanina aminotransferasa (ALT), Gammaglutamiltranspeptidasa (GGT) y hormona foliculoestimulante (FSH). Resultados: Los parámetros del perfil lipídico mostraron una disminución insignificante, mientras los niveles de GGT y FSH presentaron una disminución estadísticamente significante. Conclusiones: El tratamiento con estradiol en gel transdérmico no mostró un impacto significante en el perfil lipídico, causando un efecto benéfico en los marcadores de enfermedades cardiovasculares, sugiriendo que la dosis, el modo de administración y el tiempo de tratamiento fueron importantes para esos resultados. Además, el tratamiento con dosis baja y modo de administración transdérmico también demostró un significante efecto hepático en esa población. Así pues, ese tratamiento puede surtir efectos interesantes sobre el perfil lipídico en las mujeres brasileñas posmenopáusicas.

Transdermal estradiol and lipid profile: effects on a specific group of Brazilian postmenopausal women.

BACKGROUND: In postmenopausal women, significant changes occur that can induce cardiovascular diseases, such as atherogenic lipid profile, due to an increase in total cholesterol and LDL levels, and a decrease in HDL cholesterol levels. The hormone replacement therapy (HRT) can prevent these changes in lipid profile. OBJECTIVE: Verify the effects of HRT consisting of transdermal estradiol gel associated with medroxyprogesterone acetate on the lipid profile and biochemical parameters in Brazilian postmenopausal women. METHODS: This study is an open prospective longitudinal study, in which thirty postmenopausal women received transdermal estradiol gel (1 mg/day) continuously combined with oral medroxyprogesterone acetate (MPA) (5 mg/day) for 12 days/month. The following parameters were determined: total cholesterol, triglycerides, high density lipoprotein (HDL), low density lipoprotein (LDL), very low density lipoprotein (VLDL), glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gama glutamyl transferase (GGT) and follicle-stimulating hormone (FSH). RESULTS: The parameters of the lipid profile did not show a significant decrease, while the levels of GGT and FSH had a statistically significant decrease. CONCLUSIONS: the treatment with transdermal estradiol gel did not have a significant impact on the lipid profile, thus not resulting in a beneficial effect on cardiovascular disease markers, suggesting that the dose, administration route and the time of treatment were important for these results. Moreover, the treatment using small dose and the transdermal administration route also had a significant hepatic effect in this population. Therefore, this treatment might provide interesting effects on the lipid profile in Brazilian postmenopausal women.

Hormone replacement therapy and hemostasis: effects in Brazilian postmenopausal women.

OBJECTIVE: To evaluate the impact that administration of transdermal estradiol gel combined with medroxyprogesterone acetate (MPA) has on hemostasis. METHODS: In this open prospective longitudinal study, thirty postmenopausal women received transdermal estradiol gel (1 mg/day) continuously combined with oral MPA (5 mg/day) for 12 days/month. The following parameters were determined: prothrombin time (PT), activated partial thromboplastin time (aPTT), factors VII, X, and XII activity, fibrinogen levels, thrombin-antithrombin complex levels, protein C and S antigen, antithrombin activity, plasminogen activator inhibitor type 1 (PAI-1) antigen, tissue-type plasminogen activator (t-PA) antigen, plasminogen activity and fibrin degradation products (FbDP) antigen. They were evaluated before and after 6 months of treatment. RESULTS: There was a significant decrease in factor VII activity (P=0.001), factor X activity (P=0.016), protein C antigen (P=0.022), antithrombin activity (P=0.025), plasminogen activity (P=0.023), t-PA antigen (P=0.043) and FbDP antigen (P=0.048) compared with baseline values. CONCLUSION: The results suggest that the treatment with transdermal estradiol gel combined with MPA avoids any major activation of coagulation and does not produce any overall effect on fibrinolysis. Therefore, this treatment might provide interesting effects on hemostasis in postmenopausal Brazilian women.