Sub-acute toxicity evaluation of aqueous leaf extract from Passiflora edulis Sims f. edulis (Gulupa) in Wistar rats.

The genus Passiflora (Passifloraceae) comprises about 500 species. The Passiflora edulis stands out because of its economic and medicinal importance. It is widely planted in tropical and subtropical regions worldwide, especially in South America, the Caribbean, South Africa, and Asia. The aqueous extract of Passiflora edulis Sims f. edulis (Gulupa) leaves is used in traditional medicine for its soothing and tranquilizing effects on the central nervous system. Therefore, evaluating its safety for human use is a fundamental requirement to continue the development of new therapies within the framework of regulatory, preclinical, and clinical guidelines. Here, the sub-acute toxicity study was conducted following the Organization for Economic Cooperation and Development (OECD) guideline 407 for 28 days in Wistar albino rats. The study showed that 1000 mg/kg/day of the aqueous extract in 10 adult Wistar rats (five males and five females) was well tolerated. The hematological results are at normal levels. However, monocytopenia and eosinopenia were observed with a significant difference (P < 0,05) for both male and female rats treated with the aqueous extract of Passiflora edulis. The results show that liver and kidney function profiles were conserved. However, an increase in ALT is observed with significant differences between male and female rats treated with the extract compared to the controls. Study findings were limited to non-adverse histopathological results of a slightly increased incidence of focal periportal lymphocytic infiltrate in the liver and focal corticomedullary nephrocalcinosis in the kidney compared to control. Therefore, the aqueous extract of Passiflora edulis has a good safety profile in oral administration, was well tolerated, and did not cause any lethality or adverse effects in the sub-acute toxicity study in male and female rats. The NOAEL (no observed adverse effect level) for the 28-day subacute toxicity study was considered to be 1000 mg/kg.

Dendritogenic Potential of the Ethanol Extract from Lippia alba Leaves in Rat Cortical Neurons.

A reduced dendritic complexity, especially in regions such as the hippocampus and the prefrontal cortex, has been linked to the pathophysiology of some neuropsychiatric disorders, in which synaptic plasticity and functions such as emotional and cognitive processing are compromised. For this reason, the identification of new therapeutic strategies would be enriched by the search for metabolites that promote structural plasticity. The present study evaluated the dendritogenic potential of the ethanol extract of Lippia alba, an aromatic plant rich in flavonoids and terpenes, which has been widely used in traditional medicine for its presumed analgesic, anxiolytic, and antidepressant potential. An in vitro model of rat cortical neurons was used to determine the kinetics of the plant's effect at different time intervals. Changes in morphological parameters of the neurons were determined, as well as the dendritic complexity, by Sholl analysis. The extract promotes the outgrowth of dendritic branching in a rapid and sustained fashion, without being cytotoxic to the cells. We found that this effect could be mediated by the phosphatidylinositol 3-kinase pathway, which is involved in mechanisms of neuronal plasticity, differentiation, and survival. The evidence presented in this study provides a basis for further research that, through in vivo models, can delve into the plant's therapeutic potential.

Piper nigrum extract suppresses tumor growth and enhances the antitumor immune response in murine models of breast cancer and melanoma.

Although the antitumor effect of P. nigrum has been widely studied, research related to its possible immunomodulatory effects is relatively scarce. Here, the antitumor and immunomodulatory activity of an ethanolic extract of P. nigrum were evaluated in the murine models of 4T1 breast cancer and B16-F10 melanoma. In vitro evaluations showed that the P. nigrum extract has cytotoxic activity, induces apoptotic cell death, and has a pro-oxidant effect in both cell lines, but it regulates glucose uptake differently in both lines, decreasing it in 4T1 but not in B16-F10. P. nigrum extract significantly reduced tumor size in both models and decreased the occurrence of macrometastases in 4T1 model. Evaluation of immune subpopulations by flow cytometry revealed that the P. nigrum extract significantly increases the frequency of dendritic cells and activated CD8+ T cells and decreases the frequency of myeloid-derived suppressor like cells and Tregs in the tumor microenvironment of both models but with different dynamics. Our findings strongly suggest that the P. nigrum extract exerts immunomodulatory functions, slightly related to the modulation of cellular energy metabolism, which could ultimately contribute to the promising antitumor effect of P. nigrum.

Scutellaria incarnata Vent. root extract and isolated phenylethanoid glycosides are neuroprotective against C2-ceramide toxicity.

ETHNOPHARMACOLOGICAL RELEVANCE: Neuronal death is a central process in neurodegenerative diseases and represents a therapeutic challenge for their prevention and treatment. Scutellaria incarnata Vent. roots are used traditionally in Colombia for central nervous system conditions including those affecting cognitive functions, but their chemistry and neuroprotective action remain to be explored to understand the scientific basis for their medicinal uses. In this study, S. incarnata roots are investigated to assess whether they have neuroprotective effects that could provide some explanation for their traditional use in neurodegenerative diseases. AIM OF THE STUDY: To evaluate the neuroprotective effect of S. incarnata roots and its chemical constituents against C2-ceramide-induced cell death in Cath.-a-differentiated (CAD) cells. MATERIALS AND METHODS: S. incarnata root ethanol extract was fractionated and compounds were isolated by column chromatography; their structures were elucidated by nuclear magnetic resonance spectroscopy, mass spectrometry and infrared spectroscopy. The cytotoxic and neuroprotective effects against C2-ceramide of S. incarnata root extract, fractions and isolated compounds were assessed in CAD cells. RESULTS: S. incarnata root extract and its n-butanol fraction were not cytotoxic but showed neuroprotective effects against C2-ceramide toxicity in CAD cells. The phenylethanoid glycosides incarnatoside (isolated for the first time) and stachysoside C (12.5, 25 and 50 µg/mL) from S. incarnata roots also protected CAD cells against C2-ceramide without inducing cytotoxic effects. CONCLUSION: The observed neuroprotective effects of S. incarnata root extract and isolated phenylethanoid glycosides in CAD cells provide an ethnopharmacological basis for the traditional use of this species in Colombia for central nervous system disorders.

Tillandsia usneoides Extract Decreases the Primary Tumor in a Murine Breast Cancer Model but Not in Melanoma.

The main limits of current antitumor therapies are chemoresistance, relapses, and toxicity that impair patient quality of life. Therefore, the discovery of therapeutic alternatives, such as adjuvants to conventional therapy that modulate the intracellular oxidation state or the immune response, remains a challenge. Owing to traditional medicine, several uses of plants are known, indicating a promising antitumor and immunomodulatory effect. We evaluated the effect of ethanolic extract of T. usneoides in vitro and in vivo in models of 4T1 breast cancer and B16-F10 melanoma. In vitro evaluations with both cell lines showed that the extract has cytotoxic activity and induces apoptotic cell death. However, its effect on ROS production and glucose uptake was opposite. In vivo, only in the 4T1 model, a significant decrease in tumor size was found in animals treated with the extract, accompanied by an increase in dendritic cells and activated CD8+ T cells, and a decrease in myeloid-derived suppressor-like cells (MDSC-LC) and Tregs in the tumor microenvironment. These results suggest that T. usneoides extract antagonistically regulates tumor metabolism of 4T1 vs. B16-F10, impacting the tumor microenvironment and effective antitumor immune response, leading to a reduction in 4T1 tumor size but not on B16-F10.

Flavonoids and saponins from Passiflora edulis f. edulis leaves (purple passion fruit) and its potential anti-inflammatory activity.

OBJECTIVES: The objective of this work was to evaluate the anti-inflammatory activity of the aqueous extract, fractions and major compounds, which are isolated and identified from Passiflora edulis f. edulis (purple passion fruit) leaves extract. METHODS: For the isolation of the major compounds, reversed-phase chromatography and normal phase countercurrent chromatography were used. The separation was followed by thin layer chromatography and HPLC-DAD-ELSD. One-dimensional and two-dimensional NMR and ESI-TOF-MS/MS were used for structural elucidation. The anti-inflammatory activity was evaluated on a TPA multiple dose model of skin chronic inflammation in mice. Additionally, myeloperoxidase (MPO) and nitric oxide synthase (NOS) activity assays were performed as possible mechanisms of action studies. KEY FINDINGS AND CONCLUSIONS: The study of the butanolic fraction mainly showed the presence of saponins and flavonoids. Three minor flavonoids were detected; and three known saponins, cyclopassiflosides IX, XI and III were isolated and identified. This is the first unequivocal report of the presence of these compounds in P. edulis f. edulis leaves. The most favourable results of anti-inflammatory activity were obtained for the flavonoid-rich fraction. All the fractions and isolated compounds evaluated, presented high percentages of inhibition of nitric oxide synthase activity.

Cellular target of isoquercetin from Passiflora ligularis Juss for glucose uptake in rat soleus muscle.

Quercetin 3-O-beta-d-glucopyranoside (isoquercetin) is one of the most frequent metabolites of the Passiflora ligularis Juss. The purpose of this study was to investigate the effect of the aqueous extract and ethanol fraction from P. ligularis Juss leaves on glycaemia and the mechanism of action of isoquercetin on glucose uptake. In the glucose tolerance test, the aqueous extract and ethanol fraction from P. ligularis Juss (125 mg/kg to 500 mg/kg o. g.) reduced glycaemia and increased the hepatic and muscular glycogen content. Phytochemical analysis evidenced the dominant presence of isoquercetin in the extract and fraction from leaves of P. ligularis Juss. Isoquercetin mediates the stimulatory effect on glucose uptake independent of insulin receptor activation but, involve PI3K, MAPK, MEK/ERK pathways and de novo protein synthesis to GLUT-4 translocation. Overall findings revealed that isoquercetin and aqueous extract and ethanol fraction of P. ligularis Juss leaves might be a promising functional food or medicine for the treatment or prevention of diabetes.

Astragalin augments basal calcium influx and insulin secretion in rat pancreatic islets.

Astragalin is a flavonol glycoside with several biological activities, including antidiabetic properties. The objective of this study was to investigate the effects of astragalin on glycaemia and insulin secretion, in vivo, and on calcium influx and insulin secretion in isolated rat pancreatic islets, ex vivo. Astragalin (1 and 10 mg / kg) was administered by oral gavage to fasted Wistar rats and serum glucose and plasma insulin were measured. Isolated pancreatic islets were used to measure basal insulin secretion and calcium influx. Astragalin (10 mg/ kg) decreased glycaemia and increased insulin secretion significantly at 15-180 min, respectively, in the glucose tolerance test. In isolated pancreatic cells, astragalin (100 µM) stimulated calcium influx through a mechanism involving ATP-dependent potassium channels, L-type voltage-dependent calcium channels, the sarcoendoplasmic reticulum calcium transport ATPase (SERCA), PKC and PKA. These findings highlight the dietary coadjuvant, astragalin, as a potential insulin secretagogue that may contribute to glucose homeostasis.

Optimization of flavonoid extraction from Passiflora quadrangularis leaves with sedative activity and evaluation of its stability under stress conditions

Abstract Passiflora species have been widely used in folk medicine as tranquilizers, and previous pharmacological studies have reported sedative activity for P. quadrangularis L., Passifloraceae, leaf extracts. The aim of this work was to contribute to the standardization of P. quadrangularis leaf extract with sedative activity. For this purpose, the extraction of total flavonoids was optimized, evaluating variables such as drug-solvent ratio, extraction solvents and extraction time, using Response Surface Methodology. The stability of total and individual flavonoids on the optimized extract of P. quadrangularis leaves under stress conditions was also evaluated. Sedative activity was verified by the ethyl ether-induced hypnosis test in Swiss ICR mice. Based on the results, the highest concentration of total flavonoids was obtained at a drug-solvent ratio of 1:15 (w:v), extraction solvent EtOH:H2O (1:1, v/v) and percolation time of 48 h. Regarding stability under stress conditions, it was found that the flavonoids from the optimized extract are photostable, and practically stable under neutral hydrolysis and oxidation, but labile by acid and basic hydrolysis, with the main degradation products being identified. Finally, it was demonstrated that the optimized extract improves the sedative effect when compared to previously evaluated extract in the ethyl ether-induced hypnosis test.

Monoaminergic neurotransmission is mediating the antidepressant-like effects of Passiflora edulis Sims fo. edulis.

The genus Passiflora is popularly used to treat anxiety. Recent studies showed antidepressant-like effects of two varieties of P. edulis (edulis and flavicarpa) in mice. However, the mechanisms of antidepressant actions are still unknown. Here, the effects of P. edulis fo. edulis aqueous extract (AE, 100-300mg/kg, po), and ethyl acetate (AcOEt, 25-50mg/kg, po), butanol (BuOH, 25-50mg/kg, po) and residual aqueous (25-100mg/kg, po) fractions were investigated in the mouse forced swimming test. In addition, the involvement of monoamines in the P. edulis fractions-induced antidepressant actions was approached. HPLC analyses showed that AcOEt and BuOH, but not residual, fractions shared with AE the main peaks between 25 and 70min (UV 340nm), which are suggestive of flavonoids. Nortriptyline and fluoxetine reduced the immobility time and similar results were observed for AE, AcOEt and BuOH but not residual fractions. PCPA (inhibitor of 5-HT synthesis), AMPT (inhibitor of catecholamine synthesis) and sulpiride (selective D2 receptor antagonist), but not DSP-4 (noradrenergic neurotoxin), blocked the antidepressant actions of AcOEt and BuOH. In conclusion, AcOEt and BuOH fractions shared with AE similar phytochemical composition and antidepressant actions. Preserved 5-HT and dopamine transmissions were required for the antidepressant effects of P. edulis fractions.

Pharmacokinetics of Botanical Drugs and Plant Extracts.

BACKGROUND: Botanical drugs contain plant extracts, which are complex mixtures of compounds. As with conventional drugs, it is necessary to validate their efficacy and safety through preclinical and clinical studies. However, pharmacokinetic studies for active constituents or characteristic markers in botanical drugs are rare. OBJECTIVE: The objective of this review was to investigate the global state of the art in pharmacokinetic studies of active ingredients present in plant extracts and botanical drugs. A review of pharmacokinetics studies of chemical constituents of plant extracts and botanical drugs was performed, with a total of 135 studies published between January 2004 and February 2015 available in recognized scientific databases. Botanical preparations were mainly found in the form of aqueous extracts of roots and rhizomes. The most widely studied species was Salvia miltiorrhiza Bunge, and the compound most frequently used as a pharmacokinetic marker was berberine. CONCLUSION: Most studies were performed using the Sprague Dawley rat model, and the preparations were mainly administered orally in a single dose. Quantification of plasma concentrations of pharmacokinetic markers was performed mainly by liquid-liquid extraction, followed by high performance liquid chromatography coupled to mass spectrometry detector. In conclusion, in recent years there has been an increasing interest among researchers worldwide in the study of pharmacokinetics of bioactive compounds in botanical drugs and plant extracts, especially those from the Traditional Chinese Medicine.

Comparative central effects of the aqueous leaf extract of two populations of Passiflora edulis

ABSTRACTPassiflora edulis Sims, Passifloraceae, has been used in Brazilian traditional folk medicine to the treatment of anxiety and insomnia. P. edulis is commonly known for its economic interests in Brazil. This species exhibits significant variability in the fruit rind color, then two subpopulations has been described (P. edulis fo. flavicarpa O. Deg. (PEF); P. edulis fo. edulis (PEE)). This study compared phytochemical profile and biological actions of aqueous leaf extract of PEE and PEF. HPLC analysis showed marked distinct chromatograms to the P. edulisvarieties. However, in both extracts the major compounds observed were flavonoids C-glycosides. Behavioral studies showed that PEE (300 mg/kg, p.o.) and PEF (100 and 300 mg/kg, p.o.) reduced anxiety in the elevated plus maze test. PEE (300 and 1000 mg/kg, p.o.) and PEF (1000 mg/kg, p.o.) also induced antidepressant-like actions in the forced swimming test. PEE 1000 mg/kg significantly reduced distance moved, thus suggesting sedation. No alterations in sleeping time were observed with PEE and PEF extracts. In conclusion, despite the similarities between the biological actions observed for both P. edulis varieties, quite different phytochemical profile was herein reported. These data suggest that the anxiolytic and antidepressant actions are not due to a specific phytochemical component.

Seasonal variations in the amount of isoorientin and isovitexin in Cecropia glaziovii Sneth. leaves over a two-year period / Variación estacionaria en el contenido de isoorientina e isovitexina en hojas de Cecropia glaziovii Sneth. durante un período de dos años

Cecropia glaziovii Sneth. (Urticaceae) is a common tree from Southeast and South of Brazil, being widely used in traditional medicine to treat heart and respiratory conditions. C-glycosylflavonoids have being described as the major compounds for this genus, however, no seasonality studies of individual flavonoids was conducted for any Cecropia specie. In this work, the content of isoorientin and isovitexin in aqueous extract from the leaves of C glaziovii during a two-year period was determined by high-performance liquid chromatography with diode array detector (HPLC-DAD). Seasonal alterations in the content of these two majority C-glycosylflavonoids as well its possible correlation with the pluviosity in the period of January/2008 to January/2010 were determined. Isoorientin presented higher content in November/09 (6.04 mg/g of extract) and lower content in May/08 (1.01 mg/g of extract). The higher content of isovitexin was observed in March/09 and the lower in September/08 (11.42 and 4.47 mg/g of extract, respectively). Although they have distinct behaviors, it was not observed correlation between the values of pluviosity and the production of these C-glycosylflavonoids.

Cecropia glaziovii Sneth. (Urticaceae) es un árbol comúnmente encontrada en el Suroriente y Sur de Brasil, siendo ampliamente utilizada en la medicina tradicional para el tratamiento de problemas cardíacos y respiratorios. Flavonoides C-glucósidos vienen siendo descritos como los compuestos mayoritarios del género, sin embargo, ningún estudio de estacionalidad de flavonoides analizados de modo individual fue realizado con ninguna especie de Cecropia. En el presente trabajo, el contenido de isoorientina e isovitexina en el extracto acuoso de las hojas de C. glaziovii durante un período de dos años fue determinado por HPLC-DAD. Variaciones estacionarias en el contenido de esos dos flavonoides C-glucósidos así como la posible correlación con la pluviosidad en el periodo de Enero/2008 hasta Enero/2010 fueron determinados. Isoorientina presentó mayor contenido en Noviembre/09 (6,04 mg/g de extracto) y menos contenido en Mayo/08 (1,01 mg/g de extracto). El mayor contenido de isovitexina fue observado in Marzo/09 y el menor contenido in Septiembre/08 (11,42 y 4,47 mg/g de extracto, respectivamente). Aunque los flavonoides poseen distintos comportamientos, no fue observada correlación entre los valores de pluviosidad y la producción de esos compuestos.

Effects of Passiflora nitida Kunth leaf extract on digestive enzymes and high caloric diet in rats.

The present study investigated inhibition of pancreatic lipase and metabolic effects of high caloric diet in rats. The Passiflora nitida hydroethanol leaf extract (PNE) was used in in vitro assays or administered to rats to study dyslipidemia. Inhibition of lipase in vitro was studied by a spectrophotometric assay using orlistat as the positive control. The effects of PNE on reduction of postprandial triglyceride were studied by oral fat-overloading in rats. Metabolic alterations were induced using the cafeteria diet and 4 weeks post-treatment with PNE or orlistat and blood samples were collected and biochemical analyses were performed. Liver and retroperitoneal fat tissues were obtained to analyze weight and steatosis. IC50 (lg/mL) values for pancreatic lipase inhibition were 21.2 ± 0.8 and 0.1 ± 0.01 for PNE and orlistat, respectively. Oral administration of lipid emulsion resulted in postprandial hypertriglyceridemia at 3 h postadministration and when rats were then administered PNE and orlistat there was decreased of triglyceride levels by 15 % compared to control. Although the energy consumption by the cafeteria diet had been higher, there was no significant weight gain observed in the study groups. The cafeteria diet resulted in a significant increase of weight in the retroperitoneal fat and hypertriglyceridemia levels that could be significantly reduced by PNE and orlistat treatment. We hypothesized that PNE administration prevented the hypertriglyceridemia in rats with a high caloric diet, possibly owing to reduction of lipid absorption and pancreatic lipase inhibition.

Chemical and pharmacological aspects of the genus Cecropia.

The Cecropia genus consists of about 60 species distributed throughout Latin America, mostly in Brazil. These species are widely used in traditional medicine to treat cough, asthma, bronchitis, high blood pressure, inflammation, heart disease, and as a diuretic. In recent years, there has been an increase in research on Cecropia species, with several phytochemical and pharmacological reports. Concerning its chemical composition, C-glycosylflavonoids and proanthocyanidins have been described as the main constituents of C. glaziovii, C. hololeuca and C. pachystachya, while terpenoids and steroids have been reported in several species, including C. adenopus and C. pachystachya. Among the pharmacological properties described for the genus, the most frequently reported are hypoglycemic activity for C. obtusifolia and C. peltata, and hypotensive and central nervous system activity for C. glaziovii. The present review compiles the information available on this genus because of its ethnopharmacological relevance and the potential therapeutic uses of these species.

Phenolic content and antioxidant and antimicrobial properties of fruits of Capsicum baccatum L. var. pendulum at different maturity stages.

The phenolic content, antioxidant potential, and antimicrobial activity of extracts of different parts of the fruit from Capsicum baccatum L. var. pendulum were investigated. The analysis of phenolic content was performed by the Folin-Ciocalteu method and reversed-phase high-performance liquid chromatography. The in vitro antioxidant activity was assessed by the total reactive antioxidant potential and total antioxidant reactivity index. The antioxidant activity was positively correlated with the amount of phenolics found in each sample. The ex vivo antioxidant potential was assessed using the rat liver slice model. The antimicrobial activity was screened using Gram-positive and Gram-negative bacteria and fungi. All the extracts revealed antioxidant activity and a weak antimicrobial activity.