Abstract Introduction: Pathogenic protozoans, like Entamoeba histolytica and Trichomonas vaginalis, represent a major health problem in tropical countries; and polymeric nanoparticles could be used to apply plant extracts against those parasites. Objective: To test Curcuma longa ethanolic extract and Berberis vulgaris methanolic extracts, and their main constituents, against two species of protozoans. Methods: We tested the extracts, as well as their main constituents, curcumin (Cur) and berberine (Ber), both non-encapsulated and encapsulated in polymeric nanoparticles (NPs), in vitro. We also determined nanoparticle characteristics by photon correlation spectroscopy and scanning electron microscopy, and hemolytic capacity by hemolysis in healthy erythrocytes. Results: C. longa consisted mainly of tannins, phenols, and flavonoids; and B. vulgaris in alkaloids. Encapsulated particles were more effective (P < 0.001); however, curcumin and berberine nanoparticles were the most effective treatments. CurNPs had IC50 values (µg/mL) of 9.48 and 4.25, against E. histolytica and T. vaginalis, respectively, and BerNPs 0.24 and 0.71. The particle size and encapsulation percentage for CurNPs and BerNPs were 66.5 and 73.4 nm, and 83.59 and 76.48 %, respectively. The NPs were spherical and significantly reduced hemolysis when compared to non-encapsulated extracts. Conclusions: NPs represent a useful and novel bioactive compound delivery system for therapy in diseases caused by protozoans.
Resumen Introducción: Los protozoos patógenos, como Entamoeba histolytica y Trichomonas vaginalis, representan un importante problema de salud en los países tropicales; y se podrían usar nanopartículas poliméricas para aplicar extractos de plantas contra esos parásitos. Objetivo: Probar los extractos etanólicos de Curcuma longa y Berberis vulgaris, y sus principales constituyentes, contra dos especies de protozoos. Métodos: Probamos los extractos, así como sus principales constituyentes, curcumina (Cur) y berberina (Ber), tanto no encapsulados como encapsulados en nanopartículas poliméricas (NPs), in vitro. También determinamos las características de las nanopartículas por espectroscopía de correlación de fotones y microscopía electrónica de barrido, y la capacidad hemolítica por hemólisis en eritrocitos sanos. Resultados: C. longa tenía principalmente: taninos, fenoles y flavonoides; y B. vulgaris, alcaloides. Las partículas encapsuladas fueron más efectivas (P < 0.001); sin embargo, las nanopartículas de curcumina y berberina fueron los tratamientos más efectivos. CurNPs tenía valores IC50 (µg/mL) de 9.48 y 4.25, contra E. histolytica y T. vaginalis, respectivamente, y BerNPs 0.24 y 0.71. El tamaño de partícula y el porcentaje de encapsulación para CurNPs y BerNPs fueron: 66.5 y 73.4 nm, y 83.59 y 76.48 %, respectivamente. Los NP son esféricos y redujeron significativamente la hemólisis en comparación con los extractos no encapsulados. Conclusiones: Las NP representan un sistema de administración de compuestos bioactivos útil y novedoso para la terapia enfermedades causadas por protozoos.
Trichomonas vaginalis , Berberis vulgaris , Curcuma , Entamoeba histolytica
Resumen Objetivo: Evaluar la actividad antibacteriana de los extractos de Mimosa tenuiflora, Equisetum arvense, Syzygium aromaticum, Lippia graveolens y Aloe vera contra cepas bacterianas de S. mutans (ATCC700611) y S. sobrinus (ATCC33478) comparado con clorhexidina a 1200 µg/mL (0.12%) y la actividad coagulante en sangre humana. Materiales y métodos: Estudio comparativo, abierto, experimental, prospectivo y transversal in vitro. Se realizaron diluciones a 500 y 1000 µg/mL de cinco extractos y se probaron por triplicado contra microorganismos orales por medio de técnica de pozo en agar y en la evaluación de la actividad coagulante se probaron los cinco extractos por triplicado en sangre humana evaluando TP (tiempo de protrombina) y TTPa (tiempo de tromboplastina parcial activado) mediante coagulómetro. Resultados: El extracto de Lippia graveolens a 500 y 1000 µg/mL mostró un promedio de halos de inhibición sobre S. mutans de 26mm con respecto a clorhexidina a 1200 µg/mL que mostró un promedio de 15mm. Contra cepas de S. sobrinus mostraron un promedio de 19mm a 500 µg/mL y 23mm a 1000 µg/mL con respecto a 15mm de clorhexidina. El valor de TP (tiempo de protrombina) de la muestra de sangre fue 12.27 segundos, al aplicarle E. arvense y S. aromaticum ambos a 1000 µg/mL presentaron tiempos de 13.37 segundos. En cuanto al tiempo de tromboplastina parcial activada (TTPa) el valor de la muestra sin extracto fue 32.63 segundos, al aplicar M. tenuiflora a 500 µg/mL se aumentó el tiempo a 39.17 segundos. Conclusiones: Se concluye que Lippia graveolens tiene mejor efecto antibacteriano contra micrrorganismos orales y M. tenuiflora fue el extracto que aumentó por más tiempo el valor de TTPa.
Abstract Objective: To evaluate the antimicrobial and coagulating activity from five vegetables of ethnobotanical interest extracts (Mimosa tenuiflora, Equisetum arvense, Syzygium aromaticum, Lippia graveolens and Aloe vera). Materials and methods: It was a Comparative, open, experimental, prospective and cross-sectional study through antimicrobial evaluation of the five extracts against bacterial strains of S. mutans (ATCC700611) and S. sobrinus (ATCC33478) by means of agar well technique and an evaluation of coagulating activity by measuring TP (prothrombin time) and APTT (activated partial thromboplastin time) using a coagulometer and comparing the results with those of a healthy patient. Results: It was found that the antimicrobial activity of the extracts on S. mutans at 500 and 1000ppm is statistically significant in the extracts of E. arvense and L. graveolens (p= 0.0057) and (p= 0.0000) respectively and on strains of S. sobrinus from the extracts of A. vera (p= 0.0011) and L. graveolens (p= 0.0089) in both concentrations, which show an antimicrobial effect superior to chlorhexidine. The PT patient's (prothrombin time) value was 12.27 seconds, no statistical difference was observed with a value of (p<0.05), however, E. arvense and S. aromaticum, both at 1000ppm, presented times of 13.37 seconds and at the activated partial thromboplastin time (PTPA) the value of the patient was 32.63 seconds, highlighting M. tenuiflora at 500 ppm, which presented times of 39.17 seconds. Conclusions: The extracts described above contain chemical compounds that are valuable alternatives against microorganisms and oral treatments, and it is also very important that research suggests materials and medications that are effective in the treatment of patients and that do not represent a health risk.
The quantification of low-abundance secondary metabolites in plant extracts is an analytical problem that can be addressed by different analytical platforms, the most common being those based on chromatographic methods coupled to a high-sensitivity detection system. However, in recent years nuclear magnetic resonance (NMR) has become an analytical tool of primary choice for this type of problem because of its reliability, inherent simplicity in sample preparation, reduced analysis time, and low solvent consumption. The versatility of strategies based on quantitative NMR (qNMR), such as internal and external standards and electronic references, among others, and the need to develop validated analytical methods make it essential to compare procedures that must rigorously satisfy the analytical well-established acceptance criteria for method validation. In this work, two qNMR methods were developed for the quantification of hepatodamianol, a bioactive component of T. diffusa. The first method was based on a conventional external standard calibration, and the second one was based on the pulse length-based concentration determination (PULCON) method using the ERETIC2 module as a quantitation tool available in TopSpin software. The results show that both procedures allow the content of the analyte of interest in a complex matrix to be determined in a satisfactory way, under strict analytical criteria. In addition, ERETIC2 offers additional advantages such as a reduction in experimental time, reagent consumption, and waste generated.
Biological Products , Turnera , Goals , Magnetic Resonance Spectroscopy/methods , Plant Extracts/chemistry , Reproducibility of Results , Solvents
The usefulness of traditional plants in Mexico to treat human ailments has been known since ancient times. This work evaluated the antimicrobial, anticoagulant, antioxidant, cytotoxic, and anti-inflammatory potential of ethanolic extracts of Aloe vera, Equisetum arvense, Mimosa tenuiflora, Lippia graveolens, and Syzygium aromaticum. The antimicrobial activity of the extracts was evaluated against Streptococcus mutans and Streptococcus sorbinus; a significant inhibitory effect of the L. graveolens extract on both bacteria was observed at concentration levels of 250 µg/mL and greater. The anticoagulant activity was evaluated in terms of prothrombin time (PT) and activated partial thromboplastin time (APTT), A. vera and M. tenuiflora extracts showed no significant difference (p Ë 0.05) in PT compared with the control, and for APTT the extracts of A. vera, L. graveolens, and S. aromaticum decreased the APTT significantly (p Ë 0.05) compared with the control. The antioxidant potential by DPPH assay indicated that the E. arvense extract behaved statistically the same as the control. The cytotoxic activity was evaluated in HGF-1 cells using the fluorometric microculture cytotoxicity assay technique, and none of the extracts was toxic at 125 and 250 µg/mL concentrations. Finally, the anti-inflammatory activity was evaluated using ELISA, where the A. vera extract showed the best anti-inflammatory capacity. Further research on the search for bioactive metabolites and elucidation of action mechanisms of the most promising extracts will be carried out.
Anti-Infective Agents , Plants, Medicinal , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Anti-Inflammatory Agents/pharmacology , Anticoagulants/pharmacology , Antioxidants/pharmacology , Antioxidants/therapeutic use , Dentistry , Humans , Plant Extracts/pharmacology , Plant Extracts/therapeutic use
BACKGROUND: Parasitic infections represent one of the main public health problems in humans according to the WHO. Therefore, the need has arisen to find new treatments that can be used as an alternative cure to parasitosis. We aimed to investigate the in-vitro effects of the methanolic extract of Kalanchoe daigremontiana as well as its main component, quercetin against Entamoeba histolytica and Trichomonas vaginalis. METHODS: For this purpose, the in-vitro activity of the methanol extract of K. daigremontiana also its main component, quercetin, against trophozoites of E. histolytica and T. vaginalis was evaluated, using the microassay technique. Furthermore, the antioxidant activity was determined. Finally, the cytotoxic and cytoprotective capacity was determined using the hemolysis technique. RESULTS: The IC50 indicated that quercetin significantly (P < 0.05) inhibited the growth rate of the trophozoite stage of E. histolytica and T. vaginalis in comparison to the methanolic extract of K. daigremontiana (KalL). Also, quercetin significantly (P < 0.05) was a better antioxidant as compared with the positive control. In the evaluation of cytotoxicity effects, it could be observed that KalL as compared with quercetin exhibited more cytotoxicity against human erythrocytes. Quercetin significantly (P < 0.001) exhibited better cytoprotective activity compared to KalL. CONCLUSION: Both K. daigremontiana methanolic extract and quercetin alone demonstrated high antiparasitic activity against E. histolytica and T. vaginalis. However, the in-vivo efficacy of K. daigremontiana and quercetin also requires to be evaluated using an animal model.
BACKGROUND: Schistosomiasis has been identified as a major public health problem in tropical countries. The present study aimed to investigate the schistosomicidal effects of the methanolic extract of Argemone mexicana L. and its active component, berberine against Schistosoma mansoni on in-vitro experiments. METHODS: S. mansoni adults were used. Various concentrations of the methanolic extract (10 - 200 µg/ml) and berberine (2.5 - 50 µM) were tested from 24 to 72 h. The viability of S. mansoni was confirmed with an invertoscope-microscope. Furthermore, cytotoxic (Hemolysis test), and antioxidant (DPPH radical scavenging assay) capacities were determined. RESULTS: The viability tests on S. mansoni showed that A. mexicana at 50 µg/mL is lethal at 48 h and berberine at 10 µM is lethal at 24 h. The hemolytic activity at 1,000 µg/mL was 2.9% for A. mexicana and 90.2% for berberine. The antioxidant capacities shown by A. mexicana and berberine, were EC50 156.3 and 84.1 µg/mL, respectively. CONCLUSION: The extract of A. mexicana and berberine demonstrated high antischistosomal activities in low concentration and short exposure time on the in-vitro model.
Recently, pharmaceutical and personal care products (PPCPs) have received considerable attention because of their increasing use. Analysis of PPCPs presents a significant analytical challenge, with high-performance liquid chromatography (HPLC) in reversed-phase mode, as the most widely used analytical technique. To facilitate the optimization of the procedures that are applied in the early stages of sample preparation, a simple and fast HPLC method is proposed in this work for the separation of some PPCPs with a wide range of hydrophilicity. Two columns were evaluated (Atlantis dC18 and Discovery HS F5); as for mobile phases: a formate buffer (40 mmol L-1, pH 4) and methanol were tested in a gradient mode. The fluorinated column allowed better separation in a shorter time and better resolution for all analytes (Rs > 1). The proposed method delivered good performance for the tracing of PPCPs and is a suitable alternative to traditional C18-based HPLC methods.
Chromatography, High Pressure Liquid/methods , Cosmetics/analysis , Pharmaceutical Preparations/analysis , Chromatography, Reverse-Phase/methods , Cosmetics/chemistry , Hydrophobic and Hydrophilic Interactions , Pharmaceutical Preparations/chemistry
Strongyloidiasis is a parasitosis that represents a public health problem, in tropical regions. The present study aimed to investigate the anthelmintic effects of several extracts of Argemone mexicana, as well as its main component berberine (Ber) against the third-stage larvae (L3) of Strongyloides venezuelensis in-vitro experiments. Also, the anti-hemolytic activity of the extract, fractions, and Ber were tested in human erythrocytes. A dose-response anthelminthic bioassay demonstrated Ber as the most effective component, followed by methanolic subfraction (Fr3) and finally the crude extract of A. mexicana (Am) showing LC50 response values of 1.6, 19.5, and 92.1 µg/mL, at 96 h respectively. Also, Am, Fr3, and Ber did not produce significant hemolysis against human erythrocytes (p ≤ 0.05). Am and Fr3 showed erythrocyte protection effect capacity at the membrane level (p ≤ 0.05). Furthermore, Ber was found to have an antioxidant activity of 168.18 µg/mL. According to the results, the Fr3 of A. mexicana, and particularly Ber, exhibited potent in-vitro effects against L3 of S. venezuelensis, without hemolytic activity against human erythrocytes and presented good antioxidant capacity. In conclusion, the extracts of A. mexicana and the main component have activity against S. venezuelensis, nevertheless, further studies are required to elucidate the mechanism of action.
Anthelmintics/pharmacology , Argemone/chemistry , Berberine/pharmacology , Plant Extracts/pharmacology , Strongyloides/drug effects , Analysis of Variance , Animals , Anthelmintics/chemistry , Anthelmintics/therapeutic use , Berberine/chemistry , Berberine/therapeutic use , Biological Assay , Dose-Response Relationship, Drug , Erythrocytes/drug effects , Feces/parasitology , Hemolysis/drug effects , Humans , Larva/drug effects , Lethal Dose 50 , Male , Plant Extracts/chemistry , Plant Extracts/therapeutic use , Plant Leaves/chemistry , Plant Stems/chemistry , Rats , Rats, Wistar , Strongyloidiasis/drug therapy
Infections caused by Trichomonas vaginalis in humans are one of the main public health problems caused by sexually transmitted diseases. Objective of this study was to evaluate potential biological activity of the medicinal plant Argemone mexicana (Mexican poppy) on T. vaginalis. Methanolic extracts of the stems and leaves of A. mexicana, and different fractions were prepared with solvents of different polarities. The extracts and functional groups were detected containing sterols, triterpenes, quinones, flavonoids and, alkaloids. Extracts from both the stems and leaves of A. mexicana inhibited the growth of T. vaginalis with half-maximal inhibitory concentration value of 70.6 and 67.2 µg/ml, respectively. In the active fractions, the most abundant compounds were berberine and jatrorrhizine, with presumed antiparasitic activity.
Plant Extracts/pharmacology , Trichomonas vaginalis/drug effects , Trichomonas vaginalis/growth & development , Antineoplastic Combined Chemotherapy Protocols , Bacterial Vaccines , Cyclophosphamide , Depression, Chemical , Dose-Response Relationship, Drug , Doxorubicin , Fluorouracil , In Vitro Techniques , Leucovorin , Methanol , Plant Extracts/chemistry , Plant Leaves/chemistry , Plant Stems/chemistry , Quinones , Sterols , Triterpenes
Jatropha dioica is a popular plant used in Mexican herbal medicine to treat several diseases. Cytotoxicity, antimicrobial and antiviral activities have been reported for root extracts, while riolozatrione, 6-epi-riolozatrione, citlalitrione and jatrophatrione, among others, have been identified as the principal components. In this work, an HPLC/DAD method for the analysis of riolozatrione and other major compounds in extracts of different polarities was validated. The analysis was carried out on an AccQ-Tag column with a water-acetonitrile mixture as mobile phase. Flow rate was 0.2 mL/min, and the separation was carried out in gradient mode with UV detection set at 254 nm. The resulting method showed good reproducibility in both retention times and peak areas of riolozatrione, 6-epi-riolozatrione, citlalitrione and jatrophatrione, with relative standard variations lower than 4.5 and 10.5% respectively. In addition, this method provides a good performance for riolozatrione quantitation, with recoveries between 102 and 108% and RSDs lower than 2.5%. The polarity of the extracting solvent did not affect the performance of the chromatographic method. The developed method was applied for the analysis and quantification of riolozatrione in extracts of Jatropha dioica collected in several seasonal stages and years (2014-2017).
Antiviral Agents/pharmacology , Chromatography, High Pressure Liquid/methods , Jatropha/chemistry , Plant Extracts/analysis , Animals , Antiviral Agents/chemistry , Chlorocebus aethiops , Diterpenes/analysis , Herpesvirus 1, Human/drug effects , Mexico , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plants, Medicinal/chemistry , Seasons , Solvents/chemistry , Ultraviolet Rays , Vero Cells
Due to the biological activities of Syzygium aromaticum essential oil, its incorporation in methacrylate polymeric (Eudragit E100) nanoparticles (NP), physical characterization, and antimicrobial essays were evaluated. The clove bears great potential for applications in dentistry. The oil was obtained by hydrodistillation and oil loaded NP using the nanoprecipitation method. Particle size and polydispersity index were determined by photon correlation spectroscopy, and physical morphology by electron microscopy. Loading capacity and in vitro eugenol release were evaluated by gas mass chromatography, and the antimicrobial activity of oil loaded-NP was calculated against Streptococcus mutans. Different chemical ingredients were characterized, and eugenol was the principal compound with 51.55%. Polymer content was directly related to NP homogenous size, which was around 150 nm with spherical morphology. A 73.2% loading capacity of eugenol was obtained. Oil loaded NP presented a fickian-type release mechanism of eugenol. Antimicrobial activity to 300 µg/mL was obtained after 24 h.
Debido a las actividades biológicas del aceite esencial de Syzygium aromaticum, se evaluó su incorporación en nanopartículas (NP) de metacrilato polimérico (Eudragit E100), su caracterización y ensayos antimicrobianos. El clavo tiene un gran potencial para aplicaciones en odontología. El aceite se obtuvo por hidrodestilación y las NP cargado de aceite utilizando el método de nanoprecipitación. El tamaño de partícula y el índice de polidispersidad se determinaron mediante espectroscopia de correlación fotónica y su morfología por microscopía electrónica. La capacidad de carga y la liberación de eugenol in vitro se evaluaron mediante cromatografía de gases en masa, y la actividad antimicrobiana se evaluó contra Streptococcus mutans. Se caracterizaron diferentes ingredientes químicos, siendo el eugenol el principal compuesto con 51.55%. El contenido de polímero se relacionó directamente con el tamaño homogéneo de NP, que fue de alrededor de 150 nm con morfología esférica. Se obtuvo un 73,2% de capacidad de carga de eugenol. El aceite cargado en NP presentó un mecanismo de liberación de eugenol de tipo fickiano. La actividad antimicrobiana a 300 µg/mL se obtuvo después de 24 h.
Polymers/chemistry , Oils, Volatile/administration & dosage , Syzygium/chemistry , Nanoparticles/chemistry , Anti-Bacterial Agents/administration & dosage , Streptococcus mutans/drug effects , Eugenol/pharmacology , Oils, Volatile/pharmacology , Administration, Oral , Chromatography, Thin Layer , Drug Delivery Systems , Gas Chromatography-Mass Spectrometry , Anti-Bacterial Agents/pharmacology
Introducción: El uso indiscriminado de agentes antiparasitarios ha resultado en el establecimiento de resistencia a ellos. Por lo cual es necesario el desarrollo de nuevas alternativas de tratamiento. Los productos naturales poseen diversas cualidades como posibles coadyuvantes en terapias contra distintos agentes etiológicos, entre los que destaca sus efectos antiparasitarios. Objetivo: Evaluar la actividad antiparasitaria, antioxidante, citotóxica y citoprotectora de Berberina (Ber), Curcumina (Cur) y Quercetina (Qr). Metodología: Se prepararon soluciones de Ber, Cur y Qr grado analítico y se realizaron alícuotas a diferentes concentraciones para su evaluación en contra de: Entamoeba histolytica, Trichomonas vaginalis y Strongyloides venezuelensis, paraello, se determinó la concentración inhibitoria media (IC50), además se determinó la capacidad antioxidante (CE50) mediante la prueba de DPPH, ambos por la prueba de Probit. Mediante la técnica de hemólisis se determinó la actividad citotóxica y citoprotectora, se aplicó Anova y la prueba de Tukey para determinar la diferencia de las medias en los tratamientos evaluados. Resultados: Ber, Cur y Qr, presentaron actividad en contra de E. histolytica, T. vaginalis y S. venezuelensis in-vitro. Ber presentó IC50 de 1.7, 1.2 y 1.9 μM respectivamente siendo más efectivo en comparación de Cur con IC50 de 55.3, 40.6 y 13.7 μM o Qr con IC50 de 147.2, 93.2 y 110.9 μM, sin embargo, la mejor actividad antioxidante (EC50 = 1.1 μg/ml), citoprotectora y menos hemolítica, fue presentada por Qr (P < 0.001) en comparación con el control evaluado. Conclusiones: Los metabolitos de origen natural berberina, curcumina y quercetina, poseen actividad en contra de trofozoítos de E. histolytica, T. vaginalisy larvas de S. venezuelensis en dosis bajas comparables con los fármacos de referencia para el caso de Ber. Además, estos productos de origen natural, no sintético podrían ser objeto de futuras investigaciones para coadyuvar al tratamiento de parasitosis, ya que, en dosis bajas, mostraron actividad antioxidante sin mostrar hemólisis considerable en eritrocitos humanos.
Introduction: The indiscriminate use of antiparasitic agents has resulted in the establishment of resistance to them. Therefore, the development of new treatment alternatives is necessary. Natural products have various qualities as possible adjuvants in therapies against different etiological agents, among which its antiparasitic effects stand out. Objective: To evaluate the antiparasitic, antioxidant, cytotoxic, and cytoprotective activity of Berberine (Ber), Curcumin (Cur), and Quercetin (Qr). Methods: Analytical grade Ber, Cur, and Qr solutions were prepared, and aliquots were made at different concentrations for their evaluation against Entamoeba histolytica, Trichomonas vaginalis, and Strongyloides venezuelensis. To do this, the mean inhibitory concentration (IC50) was determined, and the antioxidant capacity (EC50) was also determined by the DPPH assay, both using the Probit statistical test. The cytotoxic and cytoprotective activity was determined by the hemolysis technique, Anova and Tukey's test were applied to determine the difference in the means in the treatments evaluated. Results: Ber, Cur, and Qr, showed activity against E. histolytica, T. vaginalis, and S. venezuelensisin-vitro. Ber presented IC50 of 1.7, 1.2, and 1.9 μM respectively, being more effective compared to Cur with IC50 of 55.3, 40.6, and 13.7 μM, or Qr with IC50 of 147.2, 93.2, and 110.9 μM, however, the best antioxidant activity (EC50 = 1.1 μg/ml), cytoprotective and less hemolytic, was presented by Qr (P < 0.001) compared to the evaluated control. Conclusions: The metabolites of natural origin berberine, curcumin, and quercetin, have activity against trophozoites of E. histolytica, T. vaginalis and larvae of S. venezuelensis in low doses comparable to the reference drugs in the case of Ber. Furthermore, these non-synthetic products of natural origin could be the subject of future research to help treat parasitosis, since in low doses, they showed antioxidant activity without showing considerable cytotoxicity in human erythrocytes.
BACKGROUND: Microscale in vitro assays are fast, simple, and inexpensive, with reduced reagent quantities, waste, and experimental animal use. However, they have low reproducibility and low correlation with the results of in vivo models, possibly due to differences in precision and accuracy in methodologies between laboratories. OBJECTIVE: The objective was the optimization and validation of an in vitro assay, carried out on microscale, to assess the inhibition of α-glucosidase activity, which is indicative of antihyperglycemic activity. METHODS: The optimization was carried out using a fractional factorial design taking into account the best inhibition percentage and the absorbance of the controls. With the optimized experimental conditions in hand, we carried out method validation. RESULTS: The optimized conditions were as follows: enzyme concentration, 0.55 U/mL; substrate concentration, 111.5 µM; and 17.5 min incubation at 37°C. A linear range between 100 and 310.2 µg/mL of acarbose (r2 0.994) was established. The RSD was <2% and the % error was <3%. The Z factor was >0.96. This method was applied to four plant extracts, one of which was found to be very active. CONCLUSION: The method was found to be accurate, precise, selective, linear, and reliable in evaluating the antihyperglycemic activity of natural extracts in vitro.
Infections caused by parasites in humans represent one of the main public health concerns. Amoebiasis, a parasitic infection caused by Entamoeba histolytica (E. histolytica), is considered endemic in Mexico, where Argemone mexicana (A. mexicana) has been used in traditional medicine to treat intestinal parasitic diseases. The objective of this work was to evaluate the potential biological activity of A. mexicana on E. histolytica. For this purpose, a methanolic extract was prepared from A. mexicana leaves, and a differential fractionation was carried out with solvents of different polarities. The inhibitory capacities of the extract and its fractions were evaluated in vitro using HM1-IMSS, a strain of Entamoeba histolytica. A. mexicana extract was found to have a growth-inhibiting activity for E. histolytica, showing IC50 = 78.39 µg/mL. The extract was characterized phytochemically, and the methanolic extract fractions were analyzed by liquid chromatography (HPLC) and mass spectrometry (MS). Berberine and jatrorrhizine were present in the active fractions, and these compounds may be responsible for the antiparasitic activity. The identification of amoebicidal activity of A. mexicana on E. histolytica gives support to the traditional use. Further studies with berberine and jatrorrhizine will be carried out to understand the mechanism involved.
Alpha-synuclein (α-syn) is an intrinsically-disordered protein that has been associated with Parkinson's disease through its deposition in an amyloid fibril form within Lewy Body. Several lines of evidence suggest that the physical association of α-syn with the mitochondrial membranes may cause membrane damage and mitochondrial dysfunction, playing an important role in disease progression. Although there is strong evidence that the N-terminus part of α-syn is essential for membrane affinity, cooperative formation of helical domains and regulation of mitochondria membrane permeability, the amino acids involve in this membrane binding is still controversial. Fluorescence spectroscopy, circular dichroism and Langmuir monolayer technique were used to elucidate this recognition process of mitochondrial membrane system by synthetic peptides derived from α-syn N-terminal segment. The results obtained in this work show that the first 15 amino acid of the α-syn N-terminal segment mainly participate in the anchoring, perturbing the membrane hydrophobic region, while the peptide corresponding to 16-30 residues interacts only with the phospholipid polar headgroup, confirming that the binding affinity of the N-terminus is nonuniform.
Mitochondrial Membranes/metabolism , alpha-Synuclein/metabolism , Amino Acid Sequence , Protein Binding , alpha-Synuclein/chemistry
Melittin is the main component of bee venom consisting of 26 amino acids that has multiple effects, including antibacterial, antiviral and anti-inflammatory in various cell types. This peptide forms pores in biological membranes and triggers cell death. Therefore it has potential as an anti-cancer therapy. However, the therapeutic application of melittin is limited due to its main side effect, hemolysis, which is especially pronounced following intravenous administration. In the present study, we formulated tetrameric melittin-carrying poly-D,L-lactic-co-glycolic acid nanoparticles (PLGA-NPs) and analyzed the lytic activity of this system on liposomes that resembles breast cancer cells. Tetrameric melittin binds avidly to PLGA-NPs with an encapsulation efficiency of 97% and retains its lytic activity demonstrating the effectiveness of PLGA-NPs as nanocarriers for this cytolytic peptide.
Delayed-Action Preparations/chemistry , Liposomes/chemistry , Melitten/chemistry , Membrane Fluidity/drug effects , Nanocapsules/chemistry , Nanocapsules/ultrastructure , Absorbable Implants , Diffusion , Drug Design , Melitten/administration & dosage
BACKGROUND: The search for new natural or synthetic products with antioxidant activity is commonly based on methods that involve reduction of either 2,2-diphenyl-1-picrylhydrazyl (DPPH) or 2-2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS). However, the reported values of the effective concentrations are highly variable, even in controls. Herein, we optimize and validate both meth-ods of determining antiradical activity. METHODS: Optimization was carried out using both a fractionated factorial design and a basic sequential simplex method, by monitoring the reduction percentage. Quercetin or Trolox were used as positive con-trol. Furthermore, for each method, linearity, precision, accuracy, robustness, plate uniformity, signal variability, and Z factor, were established. RESULTS: The optimized conditions for the DPPH method were: DPPH 280 µM in ethanol and 15 min of reaction time in the dark. The linear range was between 7 and 140 µM with an R2 value of 0.9987. The optimized conditions for the ABTS method were: ABTS adjusted to 0.7 absorbance units, 70% concen-tration in ethanol, and a reaction time of 6 min in the dark. The linear range was found to be between 1 and 70% with an R2 = 0.9991. For both methods, the accuracy and precision were within limits and the Z factor value was higher than 0.89. The applicability of each method was assessed by analyzing eight plant extracts. CONCLUSION: The DPPH and ABTS reduction methods were optimized and validated on a microscale and could be expected to be implemented in any laboratory.
Since the introduction of bone morphogenetic proteins, their use has become an invaluable ally for the treatment of bone defects. These proteins are potent growth factors, related to angiogenic and osteogenic activity. The osteoinductive capacity of recombinant bone morphogenetic protein (rhBMP) in the formation of bone and cartilage has been confirmed in in vitro studies and evaluated in clinical trials. To obtain a therapeutic effect, administration is systemic, by injection over the physiological dose. Among the disadvantages, ectopic bone formation or high morbidity in cases of spinal fusion is observed. In this review, the roles of bone morphogenetic proteins in bone repair and clinical applications are analyzed. These findings represent advances in the study of bone regeneration and application of growth factors for more predictable results.
Bone Diseases/therapy , Bone Morphogenetic Proteins/administration & dosage , Bone Regeneration/drug effects , Bone Diseases/pathology , Bone Morphogenetic Proteins/adverse effects , Humans , Injections , Ossification, Heterotopic/chemically induced , Osteogenesis/drug effects , Recombinant Proteins/administration & dosage , Recombinant Proteins/adverse effects , Spinal Fusion/methods
In this review, the composition, actions, and clinical applications of acemannan in medicine and its effectiveness as an adjunct in the treatment of diseases are presented. An electronic literature search was performed up to January 2014 for studies and research presenting data to validate the efficacy of acemannan. A total of 50 titles, abstracts and full-text studies were selected and reviewed. Acemannan has various medicinal properties like osteogenic, anti-inflammatory, and antibacterial, which accelerate healing of lesions. Also, acemannan is known to have antiviral and antitumor activities in vivo through activation of immune responses. It was concluded that Aloe vera has immense potential as a therapeutic agent. Even though the plant is a promising herb with various clinical applications in medicine and dentistry, more clinical research needs to be undertaken to validate and explain the action of acemannan in healing, so that it can be established in the field of medicine and a more precise understanding of the biological activities of these is required to develop Aloe vera as a pharmaceutical source.
Aloe/chemistry , Mannans/pharmacology , Plant Extracts/pharmacology , Animals , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Humans , Mannans/chemistry , Plant Extracts/chemistry
The aim of this work is to establish a sensitive and reliable method for the analysis of the 16 priority Environmental Protection Agency-defined polycyclic aromatic hydrocarbons (PAHs) found in water samples. Gas chromatography (GC)-mass spectrometry (MS) and high-performance liquid chromatography (HPLC)-fluorescence detection (FLD)-UV techniques are optimized to obtain an adequate resolution of all compounds. Validation of the methods is carried out, and a good performance is observed for both techniques. The HPLC-FLD-UV technique is somewhat more sensitive than the GC-MS technique for the determination of PAHs; thus, the HPLC-FLD-UV method is used to follow up both the solid-phase extraction (SPE) analysis using cartridges and discs and the liquid-liquid extraction (LLE), which are also evaluated for the extraction of the PAHs. Low recoveries between 43% and 79% are obtained using SPE cartridges, and higher values are obtained using SPE discs (56-96%) and LLE (60-105%). Better results are obtained using the LLE technique, and, thus, analysis of real water samples is carried out using this technique. LODs between 0.6 and 21 ng/L and relative standard deviations less than 15% are obtained using a spiked water sample analyzed using the full LLE HPLC-FLD-UV method.
Chromatography, High Pressure Liquid/methods , Gas Chromatography-Mass Spectrometry/methods , Polycyclic Compounds/analysis , Spectrophotometry, Ultraviolet/methods , Water Supply/analysis , Polycyclic Compounds/isolation & purification , Reference Standards , Sensitivity and Specificity
