RESUMO
BACKGROUND: Embelia ribes Burm f. (Primulaceae) is a medicinal and vulnerable woody liana distributed throughout India. Embelin, a well-recognized active phytoconstituents in berries, is commonly used in ayurvedic formulations. Due to over-exploitation, the status of the plant is vulnerable. Previous studies on this species mainly focused on its phytochemical analysis, which led to overexploitation and loss of the germplasm. METHODS AND RESULTS: In the present study, 20 RAPD and 18 ISSR markers were employed to assess genetic divergence in 40 genotypes of E. ribes collected from different parts of the Western Ghats of India. In RAPD analysis, all 40 accessions with 20 RAPD primers amplified 282 fragments, with 83.91% average polymorphism and with an average of 14.10 bands per primer. The size of amplicons varied from 200 to 2500 bp. While, ISSR primers produced 203 fragments of which 161 were polymorphic with an average of 11.28 bands per primer with 73.25% average polymorphism. The size of amplicons ranges from 200 to 2500 bp. RAPD and ISSR markers were also assessed by calculating polymorphic information content (PIC) to discriminate the genotypes; the average PIC value for RAPD, ISSR, and combined RAPD + ISSR markers obtained was more than 0.50 suggesting the informativeness of markers. UPGMA analysis based on Jaccard's similarity coefficient for RAPD, ISSR, and RAPD + ISSR data reveals that 40 accessions of E. ribes were depicted in four clusters. The clustering pattern of all individuals in PCoA analysis agreed with the UPGMA dendrograms, which further confirms the genetic relationships explained by cluster analysis. AMOVA analysis of RAPD, ISSR, and combined marker system revealed variation within the population, ranging from 41 to 44%, and among the population, it ranged from 56 to 59%. CONCLUSION: The present study provides an optimized method for evaluating the genetic diversity of Embelia ribes using RAPD and ISSR markers which are useful for further sustainable utilization and conservation of natural populations in the Western Ghats of India.
Assuntos
DNA de Plantas , Embelia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Humanos , DNA , Embelia/genética , Embelia/metabolismo , Marcadores Genéticos/genética , Variação Genética/genética , Índia , Repetições de Microssatélites/genética , Filogenia , Polimorfismo Genético/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos , DNA de Plantas/genéticaRESUMO
Chronic diseases are a serious health concern worldwide, especially in the elderly population. Most chronic diseases like cancer, cardiovascular ailments, neurodegenerative disorders, and autoimmune diseases are caused due to the abnormal functioning of multiple signaling pathways that give rise to critical anomalies in the body. Although a lot of advanced therapies are available, these have failed to entirely cure the disease due to their less efficacy. Apart from this, they have been shown to manifest disturbing side effects which hamper the patient's quality of life to the extreme. Since the last few decades, extensive studies have been done on natural herbs due to their excellent medicinal benefits. Components present in natural herbs target multiple signaling pathways involved in diseases and therefore hold high potential in the prevention and treatment of various chronic diseases. Embelin, a benzoquinone, is one such agent isolated from Embelia ribes, which has shown excellent biological activities toward several chronic ailments by upregulating a number of antioxidant enzymes (e.g., SOD, CAT, GSH, etc.), inhibiting anti-apoptotic genes (e.g., TRAIL, XIAP, survivin, etc.), modulating transcription factors (e.g., NF-κB, STAT3, etc.) blocking inflammatory biomarkers (e.g., NO, IL-1ß, IL-6, TNF-α, etc.), monitoring cell cycle synchronizing genes (e.g., p53, cyclins, CDKs, etc.), and so forth. Several preclinical studies have confirmed its excellent therapeutic activities against malicious diseases like cancer, obesity, heart diseases, Alzheimer's, and so forth. This review presents an overview of embelin, its therapeutic prospective, and the molecular targets in different chronic diseases.
Assuntos
Benzoquinonas/uso terapêutico , Embelia/química , Cardiopatias/tratamento farmacológico , Neoplasias/tratamento farmacológico , Obesidade/tratamento farmacológico , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/antagonistas & inibidores , Benzoquinonas/química , Doença Crônica , Cardiopatias/metabolismo , Humanos , Neoplasias/metabolismo , Obesidade/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismoRESUMO
Three new flavonoid glycosides, embeliaflavosides A-C (1-3), together with eight known flavonoid glycosides (4-11), were isolated from the fruits of Embelia ribes. Their structures were established based on the analyses of spectroscopic data. Compounds 1-11 were evaluated for antioxidant and α-glucosidase inhibitory activities. The results revealed that compounds 1-11 owned significant ABTS radical scavenging activity with IC50 values of 2.52-9.78 µM, and DPPH scavenging activity with IC50 values of 7.56-26.47 µM, respectively. However, α-glucosidase inhibition assay indicated that all the isolates were inactive.[Formula: see text].
Assuntos
Embelia , Ribes , Antioxidantes/farmacologia , Embelia/metabolismo , Flavonoides/farmacologia , Frutas , Inibidores de Glicosídeo Hidrolases/farmacologia , Glicosídeos/farmacologia , Estrutura Molecular , Extratos Vegetais , Ribes/metabolismo , alfa-Glucosidases/metabolismoRESUMO
A phytochemical study of the methanol extract of the leaves of Embelia schimperi resulted in the isolation of three new alkenylresorcinols, 1: â-â3: , together with the known analogs 4: â-â7: . Their structures were established by a combination of spectroscopic techniques. Compounds 1: â-â7: exhibited moderate cytotoxic activity against human cervical cancer cells HeLa-S3 and more pronounced antimicrobial properties towards bacteria and filamentous fungi. The present study falls into an ongoing research project on the characterization of bioactive phenolic lipids from plants of the family Primulaceae.
Assuntos
Anti-Infecciosos , Embelia , Anti-Infecciosos/farmacologia , Humanos , Compostos Fitoquímicos , Extratos Vegetais/farmacologia , Folhas de PlantaRESUMO
Embelin is a naturally occurring para-benzoquinone isolated from Embelia ribes (Burm. f.) of the Myrsinaceae family. It was first discovered to have potent inhibitory activity (IC50 = 4.2 µM) against α-glucosidase in this study. Then, four series of novel embelin derivatives were designed, prepared and evaluated in α-glucosidase inhibition assays. The results show that most of the embelin derivatives synthesised are effective α-glucosidase inhibitors, with IC50 values at the micromolar level, especially 10d, 12d, and 15d, the IC50 values of which are 1.8, 3.3, and 3.6 µM, respectively. Structure-activity relationship (SAR) studies suggest that hydroxyl groups in the 2/5-position of para-benzoquinone are very important, and long-chain substituents in the 3-position are highly preferred. Moreover, the inhibition mechanism and kinetics studies reveal that all of 10d, 12d, 15d, and embelin are reversible and mixed-type inhibitors. Furthermore, docking experiments were carried out to study the interactions between 10d and 15d with α-glucosidase.
Assuntos
Benzoquinonas/farmacologia , Desenho de Fármacos , Inibidores de Glicosídeo Hidrolases/farmacologia , alfa-Glucosidases/metabolismo , Benzoquinonas/síntese química , Benzoquinonas/química , Relação Dose-Resposta a Droga , Embelia/química , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
Beta-secreatse (BACE-1) and cholinesterases are clinically validated targets of Alzheimer's disease (AD), for which natural products have provided immense contribution. The multifaceted nature of AD signifies the need of multitargeted agents to tackle this disease. In the search of new natural products as dual BACE-1/cholinesterase inhibitors, a library of pure natural products was screened for inhibition of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and BACE-1. The screening efforts have identified 1,4-benzoquinone "embelin," a natural product derived from Embelia ribes displaying inhibition of all three enzymes, with IC50 values of 2.5, 5.4, and 2.1 µM, respectively. This screen has also identified isoquinoline alkaloids papaverine and L-tetrahydropalmatine as AChE inhibitors. Kinetic study has shown that embelin inhibits EeAChE and EqBChE with ki values of 4.59 and 0.57 µM, in an uncompetitive and noncompetitive manner, respectively. The interactions of embelin with allosteric peripheral anionic site of cholinesterases, has further supported the results of kinetic study. Embelin has also enhanced the activity of P-gp in LS-180 cells, the efflux pump which is involved in the clearance of amyloid-ß from AD brain. Further, the cell viability study in neuronal cell line has indicated the excellent therapeutic window of embelin. These results are indicative of the fact that embelin is a multitargeted agent playing role in stopping the formation of amyloid-ß oligomers (via inhibition of BACE-1), improves cholinergic-transmission (via inhibition of AChE/BChE) and increases amyloid-ß clearance (via P-gp induction).
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Acetilcolinesterase/química , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/química , Ácido Aspártico Endopeptidases/química , Benzoquinonas/farmacologia , Butirilcolinesterase/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Benzoquinonas/química , Butirilcolinesterase/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Embelia/química , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/química , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura MolecularRESUMO
Viral respiratory infections are raising serious concern globally. Asian medicinal plants could be useful in improving the current treatment strategies for influenza. The present study examines the activity of five plants from Bangladesh against influenza virus. MDCK cells infected with influenza virus A/Puerto Rico/8/34 (H1N1) were treated with increasing concentrations of ethyl acetate extracts, and their cytotoxicity (CC50), virus-inhibiting activity (IC50), and selectivity index (SI) were calculated. The ethyl acetate extract of fruits of Embelia ribes Burm. f. (Myrsinaceae) had the highest antiviral activity, with an IC50 of 0.2 µg/mL and a SI of 32. Its major constituent, embelin, was further isolated and tested against the same virus. Embelin demonstrated antiviral activity, with an IC50 of 0.3 µM and an SI of 10. Time-of-addition experiments revealed that embelin was most effective when added at early stages of the viral life cycle (0-1 h postinfection). Embelin was further evaluated against a panel of influenza viruses including influenza A and B viruses that were susceptible or resistant to rimantadine and oseltamivir. Among the viruses tested, avian influenza virus A/mallard/Pennsylvania/10218/84 (H5N2) was the most susceptible to embelin (SI = 31), while A/Aichi/2/68 (H3N2) virus was the most resistant (SI = 5). In silico molecular docking showed that the binding site for embelin is located in the receptor-binding domain of the viral hemagglutinin. The results of this study provide evidence that E. ribes can be used for development of a novel alternative anti-influenza plant-based agent.
Assuntos
Antivirais/farmacologia , Embelia/química , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza B/efeitos dos fármacos , Influenza Humana/virologia , Extratos Vegetais/farmacologia , Antivirais/química , Benzoquinonas/química , Benzoquinonas/farmacologia , Humanos , Vírus da Influenza A/fisiologia , Vírus da Influenza B/fisiologia , Extratos Vegetais/químicaRESUMO
The genus Malassezia comprises of extremely lipophilic yeasts secreting lipases as a vital factor for survival. They are emerging as opportunistic pathogens in medical microbiology and dermatology by causing recurring and recalcitrant infection. Combinatorial therapy is a constructive way to combat infectious diseases. In that prospect, totally 16 Indian medicinal plants were screened, among which a maximum degree of antimicrobial activity was ascertained in Embelia ribes. Subsequently embelin was identified as the bioactive principle with antagonistic potential by comparative antimicrobial assay and FTIR analysis. The MIC of embelin was determined as 400 µg/ml exhibiting â¼75% of growth inhibition. Further, a fungistatic activity based on anti-lipase potential (65-89%) of embelin has been clearly substantiated by XTT and lipase assay. In addition, embelin exhibited a synergistic effect with the antifungal drug ketoconazole (KTZ) against four different Malassezia spp. with FIC index of 0.5. Therefore, the combinations of embelin and KTZ may represent a promising therapeutic regimen to treat Malassezia infections with subjugated clinical and environmental toxicity. To the best of our knowledge, this is the first report delineating the anti-lipase activity of embelin and in vitro synergistic interaction between embelin and KTZ against Malassezia spp.
Assuntos
Antifúngicos/farmacologia , Benzoquinonas/farmacologia , Cetoconazol/farmacologia , Malassezia/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Benzoquinonas/química , Benzoquinonas/isolamento & purificação , Combinação de Medicamentos , Sinergismo Farmacológico , Embelia/química , Humanos , Índia , Lipase/efeitos dos fármacos , Malassezia/crescimento & desenvolvimento , Malassezia/patogenicidade , Testes de Sensibilidade Microbiana , Triazóis/farmacologiaRESUMO
Embelin (2,5-dihydroxy-3-undecyl-p-benzoquinone) is known for its potent anthelmintic activity, but also for wound-healing, antidiabetic, anticonvulsant, antitumour, anti-inflammatory, analgesic, hepatoprotective, antioxidant, antibacterial and antispermatogenic activities. A high-performance countercurrent chromatography method was developed for the purification of embelin from an extract of the seeds of Embelia schimperi fruit. The optimized solvent system (n-hexane-ethylacetate-ethanol-water, 7:3:7:3) resulted in the isolation of 13.9 mg of embelin, directly from 100 mg of crude extract, in a single step within a short time (40 min). Although the compound appeared to be completely pure when analysed by ultra-performance liquid chromatography (UPLC) with photo diode array detection, the purity was established as ~90% by UPLC-mass spectrometry. Furthermore, we report the fatty acid composition of the seeds of E. schimperi fruit. Nine fatty acids were quantified from the fruit seed extract by gas chromatography-mass spectrometry, with linoleic (46.4%), palmitic (21.5%) and oleic (19.6%) acids making up the largest proportions.
Assuntos
Benzoquinonas/isolamento & purificação , Distribuição Contracorrente/métodos , Embelia/química , Ácidos Graxos/análise , Extratos Vegetais/química , Sementes/química , Benzoquinonas/análise , Benzoquinonas/química , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de MassasRESUMO
BACKGROUND: Embelia schimperi has been used for the treatment of intestinal parasites especially tapeworm infestations for centuries in Ethiopia. However, there is lack of scientific based evidences regarding the efficacy, safety and phytochemical analysis of this plant despite its frequent use as an anthelmintic. This study has therefore evaluated the efficacy and acute toxicity of E. schimperi thereby generating relevant preclinical information. METHODS: The anthelmintic activities of the crude hydroalcoholic extract of E. schimperi and the isolated compound, embelin, were conducted using in vivo and in vitro models against the dwarf tapeworm, Hymenolepis nana, and the hookworm, Necator americanus, respectively. LD50 of the crude hydroalcoholic extract was determined using Swiss albino mice following the OECD guidelines. Chemical characterization of the isolated embelin was conducted using UV-spectroscopy, HPLC and NMR. RESULTS: In the acute toxicity study no prominent signs of toxicity and mortality were recorded among the experimental animals at the highest administered dose. Hence the LD50 of the plant was found to be higher than 5000 mg/kg. In vivo cestocidal activity of the crude hydroalcoholic extract of E. schimperi showed 100% parasite clearance at 1000 mg/kg, while the diammonium salt of embelin showed 85.3% parasite clearance at 750 mg/kg. The in vitro anthelminthic activity study revealed that the LC50 value of the crude extract and albendazole were 228.7 and 51.33 µg/mL, respectively. CONCLUSION: The results clearly indicated that the hydroalcoholic extract of E. schimperi and the diammonium salt of the isolated compound embelin had anthelmintic activity against hookworm larva in vitro and H. nana in vivo. Hence the findings of this study showed Embelia schimperi appears to possess some anthelmintic activity that may support the usage of these plants by local traditional healers to treat helminthic infestations.
Assuntos
Anti-Helmínticos , Embelia/química , Extratos Vegetais , Plantas Medicinais/química , Animais , Anti-Helmínticos/química , Anti-Helmínticos/farmacologia , Etiópia , Himenolepíase/parasitologia , Hymenolepis nana/efeitos dos fármacos , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologiaRESUMO
BACKGROUND: The present study was aimed at isolating an antidiabetic molecule from a herbal source and assessing its mechanism of action. METHODS: Embelin, isolated from Embelia ribes Burm. (Myrsinaceae) fruit, was evaluated for its potential to regulate insulin resistance, alter ß-cell dysfunction and modulate key markers involved in insulin sensitivity and glucose transport using high-fat diet (HFD) fed-streptozotocin (STZ) (40mg/kg)-induced type 2 diabetic rats. Molecular-dockings were performed to investigate the binding modes of embelin into PPARγ, PI3K, p-Akt and GLUT4 active sites. RESULTS: Embelin (50mg/kg b wt.) reduced body weight gain, blood glucose and plasma insulin in treated diabetic rats. It further modulated the altered lipid profiles and antioxidant enzymes with cytoprotective action on ß-cell. Embelin significantly increased the PPARγ expression in epididymal adipose tissue compared to diabetic control group; it also inhibited adipogenic activity; it mildly activated PPARγ levels in the liver and skeletal muscle. It also regulated insulin mediated glucose uptake in epididymal adipose tissue through translocation and activation of GLUT4 in PI3K/p-Akt signaling cascade. Embelin bound to PPARγ; it disclosed stable binding affinities to the active sites of PI3K, p-Akt and GLUT4. CONCLUSIONS: These findings show that embelin could improve adipose tissue insulin sensitivity without increasing weight gain, enhance glycemic control, protect ß-cell from damage and maintain glucose homeostasis in adipose tissue. GENERAL SIGNIFICANCE: Embelin can be used in the prevention and treatment of type 2 diabetes mellitus caused due to obesity.
Assuntos
Benzoquinonas/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Hipoglicemiantes/farmacologia , PPAR gama/agonistas , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Benzoquinonas/química , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Embelia/química , Frutas/química , Regulação da Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Hipoglicemiantes/química , Resistência à Insulina , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Masculino , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Obesidade/patologia , PPAR gama/metabolismo , Transporte Proteico/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
Embelin (1), a benzoquinone isolated from Embelia ribes is known to possess variety of biological activities. Despite of several promising biological activities, preclinical efforts on embelin were hampered because of its poor aqueous solubility. In order to address the solubility issue, herein, we have synthesized a series of Mannich products of embelin by treating it with various secondary amines. The synthesized compounds were screened for antiproliferative and antimicrobial activities. In cytotoxicity screening, the benzyl-piperidine linked derivative 8m was found to possess better antiproliferative activity compared to parent natural product embelin against a panel of cell lines including HCT-116, MCF-7, MIAPaCa-2 and PC-3 with IC50 values of 30, 41, 34 and 36 µM, respectively. The mechanistic study of compound 8m revealed that it exhibits cytotoxicity via induction of apoptosis and mitochondrial membrane potential loss. Further, the compounds were tested for antimicrobial activity where dimethylamino- 8a and piperidine linked derivative 8b displayed antibacterial activity against Staphylococcus aureus with MIC values of 8 and 16 µg/mL, respectively. Mannich derivatives did now show improved aqueous solubility, however their hydrochloride salts 8a·HCl, 8b·HCl and 8m·HCl showed significantly improved aqueous solubility without affecting biological activities of parent Mannich derivatives.
Assuntos
Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Benzoquinonas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Benzoquinonas/síntese química , Benzoquinonas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Embelia/química , Células HCT116 , Humanos , Células MCF-7 , Testes de Sensibilidade Microbiana , Estrutura Molecular , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
From the ethyl acetate extract of the stems of Embelia ribes (Myrsinaceae), a new alkenylresorcinol, embeliphenol A (1), together with 11 known compounds have been isolated. Their structures were elucidated on the basis of spectroscopic data. All compounds possessed significant α-glucosidase inhibitory activity in a concentration-dependent manner, except for 2 and 9. Compounds 1, 3-6, 8, and 12 showed more potent inhibitory activity, with IC50 values ranging from 10.4 to 116.7 µM, than that of a positive control acarbose (IC50 , 214.5 µM).
Assuntos
Embelia/química , Inibidores de Glicosídeo Hidrolases/química , Extratos Vegetais/química , Caules de Planta/química , Resorcinóis/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Estrutura Molecular , Resorcinóis/isolamento & purificaçãoRESUMO
CONTEXT: Traditional medicinal plants have long been used in Ethiopia to treat human and livestock ailments. Despite a well-documented rich tradition of medicinal plant use in the country, their direct antimicrobial effects are still poorly known. OBJECTIVE: To investigate the antimicrobial activity of 19 medicinal plant species that were selected based on the ethnobotanical information on their traditional use to treat infectious diseases in Ankober District. METHODS: About 23 different ethanol extracts of plants obtained by maceration of various parts of 19 medicinal plant species were studied for potential antimicrobial activity using a broth microdilution method against Bacillus cereus, Bacteroides fragilis, Candida albicans, Clostridium perfringens, Enterococcus faecalis, Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella enteritidis, Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus pyogenes. RESULTS: Plant extracts from Embelia schimperi Vatke (Myrsinaceae) showed the strongest antibacterial activity with a minimum inhibitory concentration (MIC) value of 64 µg/ml against B. cereus, L. monocytogenes, and S. pyogenes. Growth inhibitory activities were also observed for extracts of Ocimum lamiifolium Hochst. (Lamiaceae) against S. pyogenes, and those of Rubus steudneri Schweinf. (Rosaceae) against S. epidermidis at an MIC value of 128 µg/ml. Generally, 74% of ethanol extracts (17 extracts) showed antimicrobial activity against one or more of the microbial strains tested at an MIC value of 512 µg/ml or below. DISCUSSION AND CONCLUSIONS: Results confirm the antimicrobial role of traditional medicinal plants of Ankober and warrant further investigations on promising medicinal plant species so as to isolate and characterise chemicals responsible for the observed strong antimicrobial activities.
Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Embelia/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Embelia/crescimento & desenvolvimento , Etiópia , Testes de Sensibilidade Microbiana , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/crescimento & desenvolvimento , Estações do AnoRESUMO
OBJECTIVE: To study the chemical constituents from Embelia laeta. METHODS: The constituents from the EtOAc fraction of ethanol extract of Embelia laeta were separated and purified by column chromatography with silica gel and polyamide. The compounds were identified by their physiochemical proerties and spectral data. RESULTS: Eleven compounds were isolated and identified as p-sitosterol (1), beta-daucosterel (2), gallic acid (3), vanillic acid (4), rutin (5), hyperin (6), quercetin (7), kaemperol ( 8), chrysoeriol (9), physcion(10) and apigenin-7-O-glucoside(ll). CONCLUSION: Compounds 5-11 are isolated from this genus for the first time.
Assuntos
Embelia/química , Flavonas/química , Plantas Medicinais/química , Quercetina/análogos & derivados , Emodina/análogos & derivados , Emodina/química , Emodina/isolamento & purificação , Etanol/química , Flavonas/isolamento & purificação , Quercetina/química , Quercetina/isolamento & purificação , Espectrofotometria UltravioletaRESUMO
Phytochemicals exert antiviral activity and may play a potential therapeutic role in hepatitis C virus (HCV) infection. In this work, we aimed to isolate NS3 inhibitors from traditional Indian medicinal plants that were found, in our earlier study, to inhibit HCV NS3 protease activity and to evaluate their potential to inhibit HCV replication. A potent inhibitory effect of NS3 catalytic activity was obtained with Embelia ribes plant extracts. Quercetin, a ubiquitous plant flavonoid, was identified as the active substance in the fractioned extract. It was found to inhibit NS3 activity in a specific dose-dependent manner in an in vitro catalysis assay. Quercetin inhibited HCV RNA replication as analysed in the subgenomic HCV RNA replicon system. It also inhibited HCV infectious virus production in the HCV infectious cell culture system (HCVcc), as analysed by the focus-forming unit reduction assay and HCV RNA real-time PCR. The inhibitory effect of quercetin was also obtained when using a model system in which NS3 engineered substrates were introduced in NS3-expressing cells, providing evidence that inhibition in vivo could be directed to the NS3 and do not involve other HCV proteins. Our work demonstrates that quercetin has a direct inhibitory effect on the HCV NS3 protease. These results point to the potential of quercetin as a natural nontoxic anti-HCV agent reducing viral production by inhibiting both NS3 and heat shock proteins essential for HCV replication.
Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Quercetina/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/isolamento & purificação , Linhagem Celular , Relação Dose-Resposta a Droga , Embelia/química , Hepacivirus/crescimento & desenvolvimento , Humanos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Inibidores de Proteases/isolamento & purificação , Quercetina/isolamento & purificação , RNA Viral/biossíntese , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Replicação Viral/efeitos dos fármacosRESUMO
A high-fat diet (HFD) results in hyperlipidemia and an increase in oxidative stress. The purpose of this study was to investigate the preventive effect of embelin against hyperlipidemia and oxidative stress in HFD-induced obesity in rats. Male Wistar rats aged 12 weeks (150-200 g) were fed with an HFD for a period of 28 days to induce experimental obesity. HFD-induced obese rats were treated with embelin (50 mg/kg) or orlistat (10 mg/kg) for 21 days. A range of parameters were tested including body weight gain, body mass index (BMI), blood pressure, visceral fat pad weights, serum levels of glucose, insulin, leptin, apolipoprotein B (ApoB), total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), hepatic thiobarbituric acid-reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). Twenty-one days of embelin (50 mg/kg) treatment produced effects similar to orlistat in reducing body weight gain, blood pressure, visceral fat pad weight, serum lipid levels, as well as coronary artery risk and atherogenic indices of HFD-fed rats. Embelin treatment also lowered the serum levels of glucose by 24.77 %, insulin by 35.03 %, and leptin by 43.39 %. Furthermore, embelin treatment significantly (p < 0.01) decreased the hepatic TBARS levels, while increasing the SOD, CAT, and GSH levels in obese rats. The present study indicated the preventive effect of embelin in HFD-induced obesity and its related complications. Embelin could be valuable in the development of new drug therapies to prevent obesity, hyperlipidemia, and oxidative stress.
Assuntos
Fármacos Antiobesidade/uso terapêutico , Benzoquinonas/uso terapêutico , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/metabolismo , Obesidade/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/uso terapêutico , Dieta Hiperlipídica , Embelia/química , Frutas/química , Humanos , Hiperlipidemias/complicações , Hiperlipidemias/tratamento farmacológico , Lactonas/uso terapêutico , Lipase/antagonistas & inibidores , Masculino , Obesidade/complicações , Orlistate , Fitoterapia , Extratos Vegetais/uso terapêutico , Ratos , Ratos WistarRESUMO
OBJECTIVE: To study the morphological character and microscopic identification of Embelia parviflora. METHODS: Researches on the morphological character and microscopic identification of roots and stems of Embelia parviflora were carried on respectively. RESULTS: Significant microscopic characteristics of Embelia parviflora were confirmed. Such as single stone cells scattered in the root cortical, lots of stone cell groups and fiber bundles scattered in the column parts and became ring intermittently. Stem phloem was broad, large scale secretory cells scattered near cambium region and stone cell groups in ray parts. Crystal stone cells of thick and thin could be seen in powder. CONCLUSION: These features can be used as the reference for quality standard of Embelia parviflora.
Assuntos
Embelia/anatomia & histologia , Farmacognosia , Plantas Medicinais/anatomia & histologia , Embelia/citologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/citologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/citologia , Caules de Planta/anatomia & histologia , Caules de Planta/citologia , Plantas Medicinais/citologia , Pós , Controle de QualidadeRESUMO
Evidence-based herbal products with assured quality are assuming importance for complementary and alternative medicine. Traditional medicines by and large are not standardized and validated to meet the new requirements. In the present study, marker (embelin)-based standardization of a major medicinal plant, Embelia ribes and its polyherbal formulations was attempted. Conditions for the quantitative extraction of the marker compound embelin from E. ribes fruits and herbal formulations were also optimized. Reversed-phase high-performance liquid chromatography, coupled with diode array detection (RP-HPLC-DAD) for the quantification of embelin was developed and validated. Satisfactory results were obtained with respect to linearity (15-250 µg/mL), LOD (3.97 µg/mL), LOQ (13.2 µg/mL), recovery (99.4-103.8%) and precision (1.43-2.87%). The applicability of the method was demonstrated with selected phytopharmaceuticals. The present method was sensitive, accurate, simple and reproducible and therefore can be recommended for marker-based standardization, and quality assurance of E. ribes herbal formulations.
Assuntos
Benzoquinonas/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Embelia/química , Extratos Vegetais/química , Frutas/química , Modelos Lineares , Extratos Vegetais/normas , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Antioxidant and related properties of the plant Embelia ribes and embelin are well known. In the present study embelin was condensed with various aromatic substituted primary amines to yield ten new and one reported derivatives along with monomethyl embelin. All these compounds along with embelin were evaluated for in vitro antioxidant activity using 2,2'-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) diammonium salt (ABTS) and 2,2'-diphenyl-1-picryl hydrazyl (DPPH) methods. Two para-substituted embelin derivatives showed potent antioxidant activity. These compounds along with embelin were studied for analgesic and anti-inflammatory activities at 10 and 20 mg/kg doses by standard methods. Potent analgesic activity higher than the standard pentazocine was observed. Embelin and both of its derivatives almost completely abolished the acetic acid induced writhing. p-Sulfonylamine phenylamino derivative showed better anti-inflammatory activity than embelin.