Efecto del Syzygium aromaticum (clavo de olor), sobre la glicemia en ratones con diabetes experimental / Effect of Syzygium aromaticum (clove) on glycemia in mice with experimental diabetes

Cada vez se encuentra disponible en el mercado una variedad de alimentos etiquetados como «alimentos funcionales¼, con diferentes declaraciones sobre sus beneficios para la salud, incluyendo para la diabetes; los compuestos bioactivos hallados en varios alimentos justifican la investigación, en este estudio se evaluará la capacidad hipoglicemiante de una especia de cocina. Objetivo. Determinar si el extracto acuoso del Syzygium aromaticum tiene efecto sobre la glicemia en ratones con diabetes experimental (DE). Materiales y métodos. Se elaboró un extracto acuoso de Syzygium aromaticum. Los ratones fueron distribuidos en cinco grupos de cuatro unidades cada grupo (G). El G1 sin DE recibió agua destilada (AD), los cuatro grupos restantes fueron ratones con DE. La diabetes experimental se indujo con estreptozotocina vía intraperitoneal. El grupo G2 con DE se trató con agua destilada; el G3 con DE fue tratado con S. aromaticum 50 mg/kg; el G4 con DE fue tratado con S. aromaticum 200 mg/kg; el G5 con DE fue tratado con acarbosa 100 mg/kg. Estos tratamientos y la administración de agua destilada al grupo sin DE fueron en dosis única durante 5 días; la evaluación final de las glicemias se realizó 24 h después. Resultados. Los grupos G3 y G4 disminuyeron significativamente (p<0,05) la glicemia con respecto al grupo placebo. El grupo G3 no mostró diferencia significativa con respecto al grupo tratado con acarbosa, ambos mostraron un drástico efecto hipoglicemiante. Conclusiones. En condiciones experimentales, el extracto de Syzygium aromaticum tiene efecto hipoglicemiante equiparable a la droga control, y podría ser el primer paso para que esta especia se considere un alimento funcional con potencial preventivo y terapéutico para la diabetes tipo 2.

A variety of foods labeled "functional foods" are increasingly available on the market, with different claims about their health benefits, including for diabetes; the bioactive compounds found in various foods justifies the investigation, in this study the hypoglycemic capacity of a kitchen spice will be evaluated. Objective: To determine if the aqueous extract of Syzygium aromaticum has an effect on glycemia in mice with experimental diabetes (ED). Materials and methods: The aqueous extract of Syzygium aromaticum was prepared. The mice were divided into five groups of four units each group (G). Group G1 without DE received distilled water (DA), the remaining four groups where mice with ED. ED was induced with streptozotocin intraperitoneally, achieving hyperglycemic values. Group G2 with ED treated with distilled water, G3 with ED treated with Syzygium 50 mg / kg, G4 with ED treated with Syzygium 200 mg / kg, G5 with ED treated with acarbose 100 mg / kg, these treatments and the administration of distilled water to the group without ED were in a single dose for 5 days; the final evaluation of the glycemia was carried out 24 hours later. Results: The G3 and G4 groups significantly decreased (p <0.05) the glycemia with respect to the placebo group. The G3 group did not show a significant difference with respect to the group treated with acarbose, both showed a drastic hypoglycemic effect. Conclusions: Under experimental conditions, the Syzygium aromaticum extract has a hypoglycemic effect comparable to the control drug, and could be the first step for this spice to be considered a functional food with preventive and therapeutic potential for type 2 diabetes.

Efecto antidiabético de los extractos liofilizados de Guazuma ulmifolia Lam., Dracontium loretense Krause, Physalis angulata L, y Handroanthus obscurus (Bureau & K. Schum) Mattos, mediante la inhibición in vitro de la alfa α-glucosidasa / Antidiabetic effect of freeze-dried extracts of Guazuma ulmifolia Lam, Dracontium loretense Krause, Physalis angulata L, and Handroanthus obscurus (Bureau & K. Schum) Mattos, through in vitro inhibition of alpha α-glucosidase

La etnomedicina es una disciplina idónea para elegir especies vegetales con el fin de ser estudiadas farmacológicamente; las cuatro especies seleccionadas para el presente estudio se usan como hipoglucemiantes en la medicina tradicional de la Amazonía peruana. Objetivos. Estudiar la capacidad inhibitoria in vitro de los extractos de cuatro plantas de uso tradicional, sobre la actividad de la α-glucosidasa, una enzima importante involucrada en la regulación de la glicemia. Materiales y métodos. Mediante el ensayo de inhibición de la enzima α-glucosidasa se evaluaron diferentes concentraciones de cada extracto para determinar la concentración inhibitoria media (IC50) y compararlos con la droga control acarbosa. Resultados. El extracto acuoso liofilizado de Guazuma ulmifolia mostró significante efecto inhibitorio (IC50 :13,49±3,65 µg/mL), al compararlo con la droga control, acarbosa (IC50: 858,67±29,73 µg/mL) y los otros extractos. Conclusiones. Los resultados sugieren que la actividad antidiabética de la Guazuma ulmifolia estaría mediada por la inhibición de la α-glucosidasa, lo que implicaría su potencial en la reducción de la glucosa posprandial.

Ethnomedicine is an ideal discipline for choosing plant species to be studied pharmacologically; the four species selected for this study are used as hypoglycemics in the traditional medicine of the Peruvian Amazon. Objectives. To study the inhibitory capacity in vitro of the extracts of four plants of traditional use, on the activity of α-glucosidase, an important enzyme involved in the regulation of glycemia. Materials and methods. Using the inhibition test of the enzyme α-glucosidase, different concentrations of each extract were evaluated to determine the average inhibitory concentration (IC50) and to compare them with the control drug acarbose. Results. The freeze-dried aqueous extract of Guazuma ulmifolia showed a significant inhibitory effect (IC50:13,49±3,65 µg/mL) when compared with the control drug, acarbose (IC50: 858,67±29,73 µg/mL), and the other extracts. Conclusions. The results suggest that the antidiabetic activity of Guazuma ulmifolia would be mediated by the inhibition of α-glucosidase, which would imply its potential in the reduction of postprandial glucose.

Evaluación de la bioactividad de plantas medicinales cultivadas en el Perú usando la prueba de letalidad de Artemia salina / Bioactivity of medicinal plants cultivated in Peru using Artemia salina lethality test

Objetivo. Determinar la bioactividad de trece plantas medicinales peruanas a través de su capacidad citotóxica. Materiales y métodos. Se elaboraron extractos acuosos, hidroalcohólicos, o zumos liofilizados de las especies vegetales seleccionadas. La citotoxicidad in vitro fue evaluada usando la prueba de letalidad de Artemia salina, con la determinación de la concentración letal media (CL50). El potencial citotóxico de las muestras de extractos evaluados, se clasificaron en: a) no tóxico: CL50 > 1000 µg/ mL; b) baja toxicidad: 500 < CL50 ≤ 1000 µg/ mL; c) toxicidad moderada: 100 < CL50 ≤ 500 µg/ mL, y d) alta toxicidad: CL50 < 100 µg/ mL. Resultados. Los diferentes extractos del rizoma de Curcuma longa mostraron una potente actividad citotóxica, con CL50 entre 20,67 ± 7,04 y 98,14± 2,64 ug/mL. Los extractos de rizoma de Zingiber officinale, del fruto de Physalis angulata y la planta entera de Physalis angulata también mostraron actividad citotóxica con CL50 de 87,15±18,17, 323,48±18,85 y 328,92±23,08 ug/mL, respectivamente. Conclusión. Se encontró actividad citotóxica en los extractos de los rizomas de Curcuma longa, Zingiber officinale, así como el fruto y planta entera de Physalis angulata. Futuros estudios podrán determinar si la flora cultivada en el Perú puede ser una fuente para el desarrollo futuro de agentes antitumorales.

Objective. To determine the bioactivity of 13 Peruvian medicinal plants through their cytotoxic capacity. Material and methods. Aqueous, hydroalcoholic extracts or lyophilized juices of the selected plant species were elaborated. In vitro cytotoxicity was evaluated using the Artemia salina lethality test, with the determination of the mean lethal concentration (LC50). The cytotoxic potential of the samples of evaluated extracts was classified into: a) non-toxic: LC50> 1000 µg / mL, b) low toxicity: 500 < LC50 ≤ 1000 µg / mL, c) moderate toxicity: 100 < LC50≤ 500 µg / mL, and d) high toxicity: LC50 <100 µg / mL. Results. The different extracts of the Curcuma longa's rhizome showed a potent cytotoxic activity, with LC50 between 20.67 ± 7.04 and 98.14 ± 2.64 µg / mL. Zingiber officinale rhizome, Physalis angulate fruit and Physalis angulata whole plant extracts, also showed cytotoxic activity with LC50 of 87.15 ± 18.17, 323.48 ± 18.85 and 328.92 ± 23.08 µg / mL, respectively. Conclusion. Cytotoxic activity was found in the extracts of Curcuma longa, Zingiber officinale rhizomes, as well as Physalis angulata fruit and whole plant extracts. Future studies will be able to determine if the flora cultivated in Peru could be a source for future development of antitumoral agents.

Análisis fitoquímico, actividad antioxidante y hepatoprotectora del extracto acuoso liofilizado de Curcuma longa en lesiones hepáticas inducidas con tetraclorometano en ratas albinas / Phytochemical analysis, antioxidant and hepatoprotective activity of liofilizated aqueous extract of Curcuma longa on albino rats liver injury induced by tetrachloromethane

Objetivos: Realizar un análisis fitoquímico y describir la actividad hepatoprotectora y antioxidante del extracto de rizomas de Curcuma longa L. (C. longa) en un modelo murino. Materiales y métodos: La actividad antioxidante in vitro del extracto acuoso liofilizado de rizoma de C. longa L. (Fam: Zingiberaceae) se evaluó con el método de DPPH, además, también se realizó el análisis fitoquímico de tres solventes de extracción (ExEt, ExDCM y ExH2O). El ensayo in vivo se realizó en ratas albinas cepa Holtzman. Se formaron cinco grupos de tratamiento: (control normal); (control-CCl4); (Control positivo); (C. longa 100 mg/kg) y (C. longa 200 mg/kg), que fueron inducidos con CCl4 para desarrollar daño hepático. Este modelo permitió medir el efecto protector de los extractos sobre los marcadores bioquímicos (AST, ALT y ALP) en sangre. Posteriormente, se realizó un examen histopatológico de las secciones hepáticas para apoyar la inducción de la hepatoxicidad y la eficacia hepatoprotectora. Resultados: El extracto mostró un poder reductor mucho menor que el ácido ascórbico, en el tamizaje fitoquímico se encontraron compuestos fenólicos, triterpenos, quinonas, cumarinas y flavonoides, además la cantidad de curcumina encontrada fue de 0,4%-0,6%. El extracto liofilizado de C.longa mostró un efecto protector significativo (P<0,05), disminuyendo la actividad enzimática de los marcadores hepatoespecíficos. Los niveles elevados de enzimas séricas AST, ALT y ALP, se hallaron restablecidas hacia la normalización, de manera dosis dependiente, con el máximo efecto protector a dosis de 200 mg/kg. Las observaciones histopatológicas soportan las evidencias bioquímicas de hepatoprotección. Estos efectos fueron comparables a la droga estándar, silimarina. Conclusiones: Los resultados presentados en este estudio revelan fuertemente el efecto protector del extracto liofilizado de C. longa, cultivada en la región Loreto, frente a daño hepático inducido por CCl4 en experimentación animal.

Toxicidad, actividad antioxidante in vitro e hipoglicemiante in vitro e in vivo del extracto acuoso de Juglans neotropica Diels (nogal peruano) / Toxicity, in vitro antioxidant capacity and in vitro / in vivo hypoglicemiant activity of Juglans neotropica Diels (Peruvian walnut) aqueous extract

Objetivos: Evaluar la toxicidad, actividad antioxidante e hipoglicemiante del extracto acuoso liofilizado de Juglans neotropica Diels "nogal peruano". Materiales y Métodos: Se realizó una caracterización fitoquímica mediante cromatografía de gases y espectrometría de masas. La toxicidad fue medida en larvas de Artemia salina. La actividad antioxidante fue medida usando el test de 2,2-difenil-1-picrilhidrazil (DPPH). La actividad hipoglicemiante in vitro fue evaluada mediante la prueba de inhibición de α-glucosidasa; e in vivo mediante el uso de 36 ratas albinas divididas en cuatro grupos de acuerdo a la dosis suministrada (Glibenclamida 10 mg/kg, J.neotropica 100 mg/kg, 250 mg/kg y 500 mg/kg).Resultados: Dentro de los fitoconstituyentes se encontraron compuestos piranos, carbohidratos y fenoles. Con respecto a la letalidad, se encontró una CL50 de 3108 ug/mL. La mayor actividad antioxidante con el test de DPPH fue encontrada en la concentración de 20 mg/mL (86.68 ± 0.71%) con una IC50: (3.8 ± 0.31 mg/mL). La concentración de 2000 ug/mL y 1750 ug/mL mostraron la mejor actividad inhibitoria de la α-glucosidasa (IC50: 399.39 ug/mL). Se observó que había diferencia significativa (p<0.05) al comparar el grupo glibenclamida con la dosis de Juglans neotropica D 250 mg/kg (CIC: 0.95; IC95%: 0.59-0.99) y 500 mg/kg. Conclusiones: El extracto acuoso liofilizado de Juglans neotropica Diels "nogal peruano" no es tóxico, tiene buena capacidad antioxidante y actividad hipoglicemiante in vitro e in vivo a unas concentraciones de 2000 ug/mL y 250 mg/kg, respectivamente.

Sacha Inchi Oil (Plukenetia volubilis L.), effect on adherence of Staphylococus aureus to human skin explant and keratinocytes in vitro.

ETHNOPHARMACOLOGICAL RELEVANCE: Plukenetia volubilis L. (Euphorbiaceae) is a domesticated vine distributed from the high-altitude Andean rain forest to the lowlands of the Peruvian Amazon. Oil from the cold-pressed seeds, sold under the commercial name of Sacha Inchi Oil (SIO) is actually much in favour because it contains a high percentage of omega 3 and omega 6, and is hence used as a dietary supplement. SIO is also used traditionally for skin care, in order to maintain skin softness, and for the treatment of wounds, insect bites and skin infections, in a tropical context where the skin is frequently damaged. AIMS OF THE STUDY: This study was designed in order to verify whether the traditional use of SIO for skin care would have any impact on Staphylococcus aureus growth and skin adherence, as S. aureus is involved in many skin pathologies (impetigo, folliculitis, furuncles and subcutaneous abscesses) being one if the main pathogens that can be found on the skin. Therefore, our objective was to assess SIO bactericidal activity and interference with adherence to human skin explants and the keratinocyte cell line. Cytotoxicity on that cells was also determined. The activity of SIO was compared to coconut oil (CocO), which is widely used for skin care but has different unsaturated fatty acids contents. MATERIALS AND METHODS: Laboratory testing with certified oil, determined antibacterial activity against radio labelled S. aureus. Cytotoxic effects were measured with XTT on keratinocyte cells and with neutral red on human skin explants; phenol was used as cytotoxic control. Adherence assays were carried out by mixing H3-labelled S. aureus bacteria with keratinocyte cells and human skin explants, incubated with oils 2h before (to determine the inhibition of adherence, assimilated to a preventive effect) or 2h after the contact of the biological material with S. aureus (to assess the detachment of the bacteria, assimilated to a curative effect). Residual radioactivity measured after washings made it possible to determine the adherence intensity. Bactericidal effect was determined by colony counting on trypticase soy agar. RESULTS: Laboratory assays showed that SIO and CocO, tested undiluted, were not cytotoxic on keratinocytes nor human explants and were not bactericidal neither. SIO was more active as antiadherent (preventive) than CocO on keratinocytes. There was no significant difference between detachment effects (curative) of both oils on keratinocytes but SIO was almost 5 times more active on the detachment of S. aureus from human skin explants. CONCLUSION: From that study it can be concluded that the use of SIO on dermal cells is safe and efficient in the inhibition of S. aureus adherence. Our results tend to support the traditional use of undiluted SIO in skin care.

Evaluation of antiplasmodial and antileishmanial activities of herbal medicine Pseudelephantopus spiralis (Less.) Cronquist and isolated hirsutinolide-type sesquiterpenoids.

ETHNOPHARMACOLOGICAL RELEVANCE: Pseudelephantopus spiralis (Less.) Cronquist is distributed in the Caribbean, Mesoamerica and Latin America. Preparations of the plant are traditionally used in Latin America for the treatment of various diseases including fever, malaria, and spleen or liver inflammations. MATERIALS AND METHODS: Aerial parts of P. spiralis were extracted with either ethanol or distilled water. Seven hirsutinolide-type sesquiterpenoids were isolated: 8-acetyl-13-ethoxypiptocarphol (1), diacetylpiptocarphol (2), piptocarphins A (3), F (4) and D (5), (1S(*),4R(*),8S(*),10R(*))-1,4-epoxy-13-ethoxy-1,8,10-trihydroxygermacra-5E,7(11)-dien-6,12-olide (6), and piptocarphol (7). Extracts and isolated compounds (2, 3, 5-7) were screened for their in vitro antiplasmodial activity against the chloroquine-resistant Plasmodium falciparum strain FcM29-Cameroon and antileishmanial activity against three stages of Leishmania infantum. Their cytotoxicities were also evaluated against healthy VERO cell lines and J774A.1 macrophages, the host cells of the Leishmania parasites in humans. RESULTS: Aqueous extracts showed a greater inhibitory effect than alcoholic extracts, with IC50 on P. falciparum of 3.0µg/mL versus 21.1µg/mL, and on L. infantum of 13.4µg/mL versus >50µg/mL. Both extracts were found to be cytotoxic to VERO cells (CC50<3µg/mL). Sesquiterpene lactones 2 and 3 showed the best activity against both parasites but failed in selectivity. Carbon 8 hydroxylated hirsutinolides 5-7 presented the particularity of exhibiting two conformers observed in solution during extensive NMR analyses in CD3OD and UHPLC-MS. The presence of a hydroxyl function at C-8 decreased the activity of 5-7 on the two parasites and also on VERO cells. CONCLUSION: The antiplasmodial activity displayed by the aqueous extract explains the traditional use of P. spiralis in the treatment of malaria. This activity seems to be attributable to the presence of sesquiterpene lactones 2 and 3, the most active against P. falciparum. Aqueous extract and compounds 2, 3 and 6 were also active against L. infantum but lacked in selectivity due to their cytotoxicity towards macrophages. Exploring the safety and antiplasmodial efficacy of this traditional remedy will require further toxicological and in vivo studies in the light of the cytotoxicity towards healthy cell lines displayed by the aqueous extract and compounds 2 and 3.