Anti-Leishmania effect of icetexanes from Salvia procurrens.

BACKGROUND AND PURPOSE: Leishmaniasis is a globally prevalent vector-borne disease caused by parasites of the genus Leishmania. The available chemotherapeutic drugs present problems related to efficacy, emergence of parasite resistance, toxicity and high cost, justifying the search for new drugs. Several classes of compounds have demonstrated activity against Leishmania, including icetexane-type diterpenes, previously isolated from Salvia and other Lamiaceae genera. Thus, in this study, compounds of Salvia procurrens were investigated for their leishmanicidal and immunomodulatory activities. METHODS: The exudate of S. procurrens was obtained by rapidly dipping the aerial parts in dichloromethane. The compounds were isolated by column and centrifugal planar chromatography over silica gel. The effects on L. amazonensis growth, survival, membrane integrity, reactive oxygen species (ROS) generation, mitochondrial membrane potential and cytotoxicity of the compounds towards human erythrocytes, peripheral blood mononuclear cells and macrophages were evaluated. The effects on intracellular amastigote forms, nitric oxide (NO) and TNF-α production were also investigated. RESULTS: The exudate from the leaves afforded the novel icetexane 7-hydroxyfruticulin A (1) as well as the known demethylisofruticulin A (2), fruticulin A (3) and demethylfruticulin A (4). The compounds (1-4) were tested against promastigotes of L. amazonensis and showed an effective inhibition of the parasite survival (IC50 = 4.08-16.26 µM). In addition, they also induced mitochondrial ROS production, plasma membrane permeability and mitochondrial dysfunction in treated parasites, and presented low cytotoxicity against macrophages. Furthermore, all diterpenes tested reduced the number of parasites inside macrophages, by mechanisms involving TNF-α, NO and ROS. CONCLUSION: The results suggest the potential of 7-hydroxyfruticulin A (1) as well as the known demethylisofruticulin A (2),fruticulin A (3) and demethylfruticulin A (4) as candidates for use in further studies on the design of anti-leishmanial drugs.

Development of a dispersive liquid-liquid microextraction method for the evaluation of maternal-fetal exposure to cocaine employing human umbilical cord tissue.

Illicit drug use is a serious and complex public health problem, not only due to the severity of the health damage but also to the social implications, such as marginalization and drug trafficking. Currently, cocaine (COC) is among the most abused drugs worldwide with about 22 million users. Drug abuse has also been found in women during the pregnancy period, which has shed light on a new group for epidemiology. The diagnosis of COC use in these cases usually depends largely on the mother's reports, which in several cases omit or deny consumption. Therefore, considering physical-chemical methods of sample preparation and exposure biomarkers, the development of analytic toxicological methods can help to confirm drug use during pregnancy. Thus, the objective of the present work was to develop an analytical method based on dispersive liquid-liquid microextraction for the determination of COC analytes, using umbilical cord tissue as an alternative biological matrix, and detection by gas chromatography coupled to mass spectrometry. Therefore, after optimization, the dispersive liquid-liquid microextraction method was fully validated for quantification of COC, benzoylecgonine, cocaethylene, ecgonine, ecgonine methyl ester and norcocaine. The limits of detection were between 15 and 25 ng/g, the limits of quantification were 30 ng/g for ecgonine and 25 ng/g for the other analytes. Linearity ranged from the limits of quantification to 1,000 ng/g. Coefficients of variation for intra-assay precision were <18.5%, inter-assay was <8.75% and bias was <16.4% for all controls. The developed method was applied in 10 suspected positive samples, based on the mother's report and maternal urine screening and confirmation. COC, benzoylecgonine, ecgonine and ecgonine methyl ester were quantified in four umbilical cords with concentrations that ranged from 39.6 to 420.5 ng/g.

Pharmacological evaluation of a traditional Brazilian medicinal plant, Monteverdia ilicifolia. Part I - Preclinical safety study.

ETHNOPHARMACOLOGICAL RELEVANCE: Monteverdia ilicifolia (Maytenus ilicifolia, Celastraceae), known as "espinheira-santa", has been widely used in Brazil to manage mainly gastrointestinal diseases. This species has been listed in the Brazilian Pharmacopeia and in the National List of Essential Medicines (RENAME). Considering that clinical studies about M. ilicifolia are rare, our group has been performing a broader project designed to evaluate the efficacy of M. ilicifolia capsules in a clinical trial, for this reason, approaches to provide safety to those patients are relevant. AIM OF THE STUDY: We aimed to investigate the potential pharmacokinetic interaction and hepatotoxicity and intestinal toxicity of an aqueous extract of M. ilicifolia and its main phytocompounds, catequin, epicatequin, and quercetin. METHODS AND MATERIALS: Slices of liver and intestine of Wistar rats were incubated with different concentrations of M. ilicifolia extract or isolated compounds (catechin, epicatechin and quercetin). Commercial kits were used to evaluate enzyme activities of CYP2D6 and CYP3A4 isoforms, as well as cell viability (MTT) assay and intracellular enzymes leakage, specifically lactate dehydrogenase (LDH), alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT) were studied. RESULTS: Incubation with M. ilicifolia extract, catechin, epicatechin and quercetin did not affect significantly any evaluated parameter in intestines. The intracellular enzymes leakages, CYP2D6, LDH and AST, were increased with M. ilicifolia extract and quercetin in liver slices. CONCLUSIONS: Our in vitro findings highlighted, for the first time, the potential hepatotoxicity induced by an aqueous extract of M. ilicifolia, consequently this species and its products should be avoided in liver diseases, supporting that studies of safety must be performed including in the context of traditional medicinal plants.

Achyrocline satureioides as an adjuvant therapy for the management of mild viral respiratory infections in the context of COVID-19: Preliminary results of a randomized, placebo-controlled, and open-label clinical trial.

We evaluated the impact of an Achyrocline satureioides inflorescence infusion on the clinical outcomes of viral respiratory infections, including those caused by SARS-CoV-2, in a monocentric, randomized, open-label, placebo-controlled clinical trial. Patients with symptoms of viral respiratory infection, including suspected cases of COVID-19, were included and assigned to receive either A. satureioides (n = 57) or Malus domestica (n = 67) infusions twice a day for 14 days. All participants were included before the RT-PCR results, performed using a nasopharyngeal swab. The patients were further divided into subgroups according to real-time polymerase chain reaction results: SARS-CoV-2-positive and SARS-CoV-2-negative subgroups for statistical analyses. We assessed clinical outcomes, such as the latency to resolution of cough, dyspnea, fever, sore throat, chest pain, smell and taste dysfunctions, diarrhea, nausea, abdominal pain, and loss of appetite; hospitalization; and mortality with questionnaires and medical records. The subjects that received early A. satureioides infusion showed a significant reduction in the average number of days with respiratory and neurological symptoms compared with the control group (M. domestica infusion). We conclude that A. satureioides is a safe agent and, in combination with standard care, improves viral respiratory infection symptoms, especially those related to COVID-19.

Achyrocline satureioides review: From the pharmacochemical diversity to the technological development of products.

Achyrocline satureioides (Lam.) DC (Asteraceae) is a native species of the southeastern subtropical and temperate region of South America, popularly known as "marcela" or "macela". This species is recognized, in traditional medicine, by diverse biological activities such as digestive, antispasmodic, anti-inflammatory, antiviral, sedative, hepatoprotective, among others. Some of these activities have been related to the presence of phenolic compounds, including flavonoids, phenolic acids, terpenoids in the essential oils, coumarins and phloroglucinol derivatives reported to the species. The approaches on the technological development of phytopharmaceutical products of this species provided relevant advances in the optimization of the extraction and product obtention, especially spray-dried powders, hydrogels, ointments, granules, films, nanoemulsions and nanocapsules. The most relevant biological activities described for the extracts or derivative products from A. satureioides were antioxidant, neuroprotective, antidiabetic, antiobesity, antimicrobial, anticancer effects, and obstructive sleep apnea syndrome. The scientific and technological findings reported for the species, in conjunction with its traditional use and cultivation, reveal the high potential of the species for diverse industrial applications.

The challenge of improving pterostilbene (PTS) solubility for solid and semi-solid dosage forms: The obtention of binary and ternary systems.

Pterostilbene (PTS) is a drug candidate with low water solubility and poor bioavailability. On the other hand, drug:cyclodextrins complexes frequently provide bulk powders with low drug concentrations, which is crucial for obtention solid or semi-solid pharmaceutical dosage forms. In order to determine the optimal conditions for enhancing the solubility of PTS:BCD (ß-cyclodextrin) complex, a Box-Behnken design was performed. Although the optimal conditions have been applied, low complexation efficiency (0.127) and the bulk powder remained. A PTS:BCD:HPMC (HPMC, hydroxypropyl methylcellulose) ternary system was developed to overcome this limitation, comparing two media, water and a mixture of ethanol-water. When ethanol was used as a co-solvent, the PTS:BCD:HPMC ternary system (freeze-dried) contained 116.65 ± 1.40 mg/g of PTS. This value was 3.4-fold higher than the PTS content observed when the same ternary system was obtained in aqueous media (34.8 mg/g) and 2.8-fold higher than the PTS content observed for PTS:BCD complex (freeze-dried) obtained using ethanol as a co-solvent. Dissolution tests revealed that after 120 min, in a buffer with a pH value of 1.2, only 43% of PTS dissolved. In contrast, 80% and 90% of PTS were dissolved from the PTS:BCD complex and PTS:BCD:HPMC ternary system, respectively. Moreover, the dissolution was fast in a buffer with a pH value of 6.8. PTS:BCD complex reached the maximum PTS dissolution at 75 min and PTS:BCD:HPMC at 45 min. In summary, the results of this study demonstrated, for the first time, that low-bulk powders with a high content of PTS can be obtained from PTS:BCD:HPMC ternary systems using ethanol as a co-solvent. This new finding offers a valuable alternative for producing solid or semi-solid formulations containing highly soluble PTS.

Landscape-scale forest cover drives the predictability of forest regeneration across the Neotropics.

Abandonment of agricultural lands promotes the global expansion of secondary forests, which are critical for preserving biodiversity and ecosystem functions and services. Such roles largely depend, however, on two essential successional attributes, trajectory and recovery rate, which are expected to depend on landscape-scale forest cover in nonlinear ways. Using a multi-scale approach and a large vegetation dataset (843 plots, 3511 tree species) from 22 secondary forest chronosequences distributed across the Neotropics, we show that successional trajectories of woody plant species richness, stem density and basal area are less predictable in landscapes (4 km radius) with intermediate (40-60%) forest cover than in landscapes with high (greater than 60%) forest cover. This supports theory suggesting that high spatial and environmental heterogeneity in intermediately deforested landscapes can increase the variation of key ecological factors for forest recovery (e.g. seed dispersal and seedling recruitment), increasing the uncertainty of successional trajectories. Regarding the recovery rate, only species richness is positively related to forest cover in relatively small (1 km radius) landscapes. These findings highlight the importance of using a spatially explicit landscape approach in restoration initiatives and suggest that these initiatives can be more effective in more forested landscapes, especially if implemented across spatial extents of 1-4 km radius.

Green Analytical Toxicology for the Determination of Cocaine Metabolites.

Brazil is the third largest contributor to Green Analytical Chemistry, and there is significant participation of toxicologists in the development and improvement of environmental techniques. Currently, toxicologists have their own strategies and guidelines to promote the reduction/replacement or elimination of solvents, reduce the impacts of derivatization and save time, among other objectives, due to the peculiarities of toxicological analysis. Thus, this review aims to propose the concept of Green Analytical Toxicology and conduct a discussion about its relevance and applications specifically in forensic toxicology, using the microextraction methods developed for the determination of cocaine and its metabolites as examples.

Iridoids as a Potential Hepatoprotective Class: A Review.

BACKGROUND: Liver disease rates are gradually increasing over the years, becoming a severe public health problem. The indiscriminate use of drugs associated with a rich fat diet, high consumption of alcoholic beverages, and exposure to viral infections and lipid peroxidative products are considered the chief factors for developing hepatic disorders. Owing to the absence of reliable hepatoprotective drugs in the therapeutic arsenal, since they present a high incidence of adverse reactions and/or lack of efficacy in some cases, liver diseases are widely treated with medicinal plants. Among them are the plants producing iridoids, which are believed to be good remedies for liver disease due to their bitter taste. The hepatoprotective effect of iridoids and extracts, rich in these compounds, has been demonstrated, both in vitro and in vivo. OBJECTIVE: This review aims to scrutinize the available literature related to the hepatoprotective activity of iridoids. METHODS: The information was obtained from scientific databases (Science Direct, PubMed, Web of Science, Scopus, ACS Publications, Wiley Online Library) until December, 2021. RESULTS AND CONCLUSION: A total of 63 hepatoprotective iridoids were found, including aucubin, catalpol and picroliv, a mixture of two iridoids. They are the target of a high number of studies, which revealed their protective action against different hepatotoxic agents and detailed action mechanisms.

Subtribe Hyptidinae (Lamiaceae): A promising source of bioactive metabolites.

ETHNOPHARMACOLOGICAL RELEVANCE: The subtribe Hyptidinae contains approximately 400 accepted species distributed in 19 genera (Hyptis, Eriope, Condea, Cantinoa, Mesosphaerum, Cyanocephalus, Hypenia, Hyptidendron, Oocephalus, Medusantha, Gymneia, Marsypianthes, Leptohyptis, Martianthus, Asterohyptis, Eplingiella, Physominthe, Eriopidion and Rhaphiodon). This is the Lamiaceae clade with the largest number of species in Brazil and high rates of endemism. Some species have been used in different parts of the world mainly as insecticides/pest repellents, wound healing and pain-relief agents, as well as for the treatment of respiratory and gastrointestinal disorders. AIM OF THE REVIEW: This review aims to discuss the current status concerning the taxonomy, ethnobotanical uses, phytochemistry and biological properties of species which compose the subtribe Hyptidinae. MATERIALS AND METHODS: The available information was collected from scientific databases (ScienceDirect, Pubmed, Web of Science, Scopus, Google Scholar, ChemSpider, SciFinder ACS Publications, Wiley Online Library), as well as other literature sources (e.g. books, theses). RESULTS: The phytochemical investigations of plants of this subtribe have led to the identification of almost 300 chemical constituents of different classes such as diterpenes, triterpenes, lignans, α-pyrones, flavonoids, phenolic acids and monoterpenes and sesquiterpenes, as components of essential oils. Extracts, essential oils and isolated compounds showed a series of biological activities such as insecticide/repellent, antimicrobial and antinociceptive, justifying some of the popular uses of the plants. In addition, a very relevant fact is that several species produce podophyllotoxin and related lignans. CONCLUSION: Several species of Hyptidinae are used in folk medicine for treating many diseases but only a small fraction of the species has been explored and most of the traditional uses have not been validated by current investigations. In addition, the species of the subtribe appear to be very promising as alternative sources of podophyllotoxin-like lignans which are the lead compounds for the semi-synthesis of teniposide and etoposide, important antineoplastic agents. Thus, there is a wide-open door for future studies, both to support the popular uses of the plants and to find new biologically active compounds in this large number of species not yet explored.

In vitro protective effect of topical nanoemulgels containing Brazilian red propolis benzophenones against UV-induced skin damage.

The overexposure of the skin to ultraviolet (UV) radiation may lead to oxidative stress, resulting in severe damage. The prevention of skin injuries through the topical application of natural compounds rich in antioxidants, such as propolis extracts, has shown promising results. In Brazil, the "red propolis" extract has stood out due to its complex constitution, based mainly on polyprenylated benzophenones (BZP). However, although the use of red propolis extracts has been shown to be encouraging, their addition in topical formulations is limited by the low solubility of BZP. For this reason, this study aimed to develop topical nanoemulgels containing Brazilian red propolis (BRP) extract to increase the potential of topical application, and the evaluation of skin protection against UVA/UVB radiation damage by means of protein carbonylation, protein thiol content and TBARS assays. The nanoemulgels were obtained by adding gelling polymer to nanoemulsions that were previously prepared by spontaneous emulsification. In this sense, a nanoemulgel containing BRP extract-loaded nanoemulsions (H-NE) and a nanoemulgel containing BRP extract-loaded nanoemulsions with DOTAP (H-NE/DT) were prepared. The physicochemical characterization of nanoemulgels showed monodisperse populations of 200-300 nm. The H-NE zeta potential was -38 mV, while that of H-NE/DT was +36 mV. BZP content in the formulations was around 0.86 mg g-1. These parameters remained stable for 90 days under cold storage. H/NE and H-NE/DT presented a non-Newtonian pseudoplastic rheological behavior. Permeation/retention studies, through porcine ear skin, showed the highest BZP retention (18.11 µg cm-2 after 8 h) for H-NE/DT, which also demonstrated, in an in vitro study, the highest ability to protect skin against oxidative damage after UVA/UVB radiation exposure. The results concerning the antioxidant activity revealed that formulations containing the BRP n-hexane extract were the most promising in combating oxidative stress, probable due to the presence of polyprenylated BZP. Altogether, the outcomes of this study suggest that nanoemulgels have suitable characteristics for topical application, and may be an alternative for the prevention of oxidative skin damage caused by UVA/UVB radiation.

Hypericum species: An analysis on the patent technologies.

Hypericum (Hypericaceae) is a genus that comprises approximately 500 species around the world. The industrial relevance of these plants is based on the occurence of specialized metabolites that exhibit a range of pharmaceutical potential. Besides that, several species are relevant due to their ornamental value. Taking to account the vast market worth of products and processes involving Hypericum, the present study aims to provide a comprehensive overview of patents concerning this subject between 2007and 2017. For this purpose, a survey was performed in free databases (Espacenet®, PatentScope® and Google Patents®) using the keyword Hypericum in the patents title or title plus abstract. The documents were then organized by groups (medicinal and non-medicinal approaches), subgroups, type of applicants and countries. Espacenet® was chosen to data analysis, and a total of 174 patents were found. The majority of the applicants are from China and companies appear as the principal owners of patents. Several technologies are not intended for medicinal purposes, being mainly related to the development of new cultivars for ornamental uses. Concerning the medicinal approaches, the chief subject is related to extraction and incorporation into formulations. The main species cited in the documents is H. perforatum and the therapeutic use is for central nervous system diseases. In general, this study covers the patents published in recent years hoping to boost the scientists and companies that invest in Hypericum researches to visualize the state of art, opportunities and challenges for innovation in this area.

Intestinal permeability enhancement of benzopyran HP1-loaded nanoemulsions.

The benzopyran HP1, a compound isolated from Hypericum polyanthemum, has demonstrated significant opioid-mediated antinociceptive activity after its oral administration. Despite the pharmacological potential, the poor aqueous solubility limits the oral absorption of this compound. For this reason, HP1 has been alternatively incorporated in lipid-based drug delivery systems. Given that nanoemulsions showed higher antinociceptive action than the free compound in a previous report, in this study, the main objective was to investigate the intestinal transport mechanisms of this system. The Ussing chamber model and rat jejunum were selected for this purpose. The apparent permeability coefficient of HP1 increased approximately 5.3 times after its incorporation in nanoemulsions. Considering that the absorptive transport of HP1 was significantly higher than the secretory transport, the participation of active transporters was suggested. The amount of HP1 in the acceptor chamber was reduced during permeability assays performed at 4 °C, supporting the hypothesis that active transporters are involved in the intestinal transport of this compound. The amount of free fatty acids released from nanoemulsion was approximately 60% after 90 min, demonstrating that part of this system is disassembled before absorption. Nanoemulsion constituents would be able to form new structures with biological constituents, leading to a rapid solubilization of HP1. A mucoadhesion rate of 50% was achieved by nanoemulsion after 30 min, which would also contribute to explain the higher absorption of this system. The particle size of the nanoemulsion is also compatible with endocytosis-mediated transport. Taken together, these results suggest that nanoemulsions containing HP1 could be efficiently delivered to humans considering that different absorption mechanisms are exploited.

Combining discovery and targeted proteomics reveals a prognostic signature in oral cancer.

Different regions of oral squamous cell carcinoma (OSCC) have particular histopathological and molecular characteristics limiting the standard tumor-node-metastasis prognosis classification. Therefore, defining biological signatures that allow assessing the prognostic outcomes for OSCC patients would be of great clinical significance. Using histopathology-guided discovery proteomics, we analyze neoplastic islands and stroma from the invasive tumor front (ITF) and inner tumor to identify differentially expressed proteins. Potential signature proteins are prioritized and further investigated by immunohistochemistry (IHC) and targeted proteomics. IHC indicates low expression of cystatin-B in neoplastic islands from the ITF as an independent marker for local recurrence. Targeted proteomics analysis of the prioritized proteins in saliva, combined with machine-learning methods, highlights a peptide-based signature as the most powerful predictor to distinguish patients with and without lymph node metastasis. In summary, we identify a robust signature, which may enhance prognostic decisions in OSCC and better guide treatment to reduce tumor recurrence or lymph node metastasis.

Structural diversity and biological activities of phloroglucinol derivatives from Hypericum species.

Plants of the genus Hypericum (Hypericaceae) are used in folk medicine all over the world, H. perforatum being the most well-known species. Standardized extracts of this plant are commercially-available to treat mild to moderate depression cases. The present review summarizes the literature published up to 2016 concerning the phloroglucinol derivatives isolated from Hypericum species, together with their structural features and biological activities. These phytochemical studies led to the isolation of 101 prenylated phloroglucinols, chromanes and chromenes, 35 dimeric acylphloroglucinols, 235 polycyclic polyprenylated acylphloroglucinols, 25 simple benzophenones and 33 phloroglucinol-terpene adducts. These compounds show a diverse range of biological activities, such as antimicrobial, cytotoxic, antinociceptive and antidepressant-like effects.

Intestinal permeability determinants of norfloxacin in Ussing chamber model.

Recently, many efforts are taken to identify the intestinal uptake and efflux transporters since they are responsible for the absorption of many drugs as their interactions. Norfloxacin (NFX) is a fluoroquinolone that presents low solubility and low permeability, and as a consequence, low bioavailability. In this context, the aim of this study is evaluate for the first time the intestinal permeability mechanisms of NFX by Ussing chamber model. The low permeation of NFX at low temperature, where the efflux pumps are not active, reveals that NFX permeation is transporter-dependent. The permeation study at different level of intestine demonstrated that NFX passage is in the decrescent order: ileum > jejunum > duodenum > colon, probably attributed to transporters that are expressed differently along the intestinal tract. NFX intestinal flow was evaluated in the presence of many inhibitors and substrates to identify the uptake and efflux transporters implicate in NFX permeability mechanism. It could be observed that BCRP and MRPs are involved in the NFX efflux and PEPT1, PMAT and OCT in the NFX uptake transport. Furthermore, this work revealed that NFX has itself an affinity for OCTN and OATP, demonstrating that NFX could inhibit these transporters and influence the absorption of other drugs. The updated description of NFX intestinal permeability factors could contribute to the development of rational pharmaceutical formulations that could circumvent the efflux problems and consequently improve NFX biopharmaceutical properties and avoid drug-drug interactions.

Cyclodextrin based nanosponge of norfloxacin: Intestinal permeation enhancement and improved antibacterial activity.

Nanosponges are a novel class of hyperbranched cyclodextrin-based nanostructures that exhibits remarkable potential as a drug host system for the improvement in biopharmaceutical properties. This work aims the development of cyclodextrin-based nanosponge of norfloxacin to improve its physicochemical characteristics. ß-cyclodextrin was used as base and diphenyl carbonate as crosslinker agent at different proportions to produce nanosponges that were evaluated by in vitro and in vivo techniques. The proportion cyclodextrin:crosslinker 1:2 M/M was chosen due to its higher encapsulation efficiency (80%), revealing an average diameter size of 40 nm with zeta potential of -19 mV. Norfloxacin-loaded nanosponges exhibited higher passage of norfloxacin in comparison to norfloxacin drug alone by Ussing chamber method. The nanosponge formulation also revealed a mucoadhesive property that could increase norfloxacin absorption thus improving its antibiotic activity in an in vivo sepsis model. Therefore, nanosponges may be suitable carrier of norfloxacin to maximize and facilitate oral absorption.

Early metabolic response after resistance exercise with blood flow restriction in well-trained men: a metabolomics approach.

The present study aimed to compare the early metabolic response between high-load resistance exercise (HL-RE) and low-load resistance exercise with blood flow restriction (LL-BFR). Nine young, well-trained men participated in a randomized crossover design in which each subject completed LL-BFR, HL-RE, or condition control (no exercise) with a 1-week interval between them. Blood samples were taken immediately before and 5 min after the exercise sessions. Nuclear magnetic resonance spectroscopy identified and quantified 48 metabolites, 6 of which presented significant changes among the exercise protocols. The HL-RE promoted a higher increase in pyruvate, lactate, and alanine compared with the LL-BFR and the control. HL-RE and LL-BFR promoted a higher increase in succinate compared with the control; however, there was no difference between HL-RE and LL-BFR. Also, while there was no difference in acetoacetate between HL-RE and LL-BFR, a greater decrease was observed in both compared with the control. Finally, LL-BFR promoted a greater decrease in choline compared with the control. In conclusion, this study provides by metabolomics a new insight in metabolic response between LL-BFR and HL-RE by demonstrating a distinct response to some metabolites that are not commonly analyzed.

CellNetVis: a web tool for visualization of biological networks using force-directed layout constrained by cellular components.

BACKGROUND: The advent of "omics" science has brought new perspectives in contemporary biology through the high-throughput analyses of molecular interactions, providing new clues in protein/gene function and in the organization of biological pathways. Biomolecular interaction networks, or graphs, are simple abstract representations where the components of a cell (e.g. proteins, metabolites etc.) are represented by nodes and their interactions are represented by edges. An appropriate visualization of data is crucial for understanding such networks, since pathways are related to functions that occur in specific regions of the cell. The force-directed layout is an important and widely used technique to draw networks according to their topologies. Placing the networks into cellular compartments helps to quickly identify where network elements are located and, more specifically, concentrated. Currently, only a few tools provide the capability of visually organizing networks by cellular compartments. Most of them cannot handle large and dense networks. Even for small networks with hundreds of nodes the available tools are not able to reposition the network while the user is interacting, limiting the visual exploration capability. RESULTS: Here we propose CellNetVis, a web tool to easily display biological networks in a cell diagram employing a constrained force-directed layout algorithm. The tool is freely available and open-source. It was originally designed for networks generated by the Integrated Interactome System and can be used with networks from others databases, like InnateDB. CONCLUSIONS: CellNetVis has demonstrated to be applicable for dynamic investigation of complex networks over a consistent representation of a cell on the Web, with capabilities not matched elsewhere.

Human Regulatory Protein Ki-1/57 Is a Target of SUMOylation and Affects PML Nuclear Body Formation.

Ki-1/57 is a nuclear and cytoplasmic regulatory protein first identified in malignant cells from Hodgkin's lymphoma. It is involved in gene expression regulation on both transcriptional and mRNA metabolism levels. Ki-1/57 belongs to the family of intrinsically unstructured proteins and undergoes phosphorylation by PKC and methylation by PRMT1. Previous characterization of its protein interaction profile by yeast two-hybrid screening showed that Ki-1/57 interacts with proteins of the SUMOylation machinery, the SUMO E2 conjugating enzyme UBC9 and the SUMO E3 ligase PIAS3, which suggested that Ki-1/57 could be involved with this process. Here we identified seven potential SUMO target sites (lysine residues) on Ki-1/57 sequence and observed that Ki-1/57 is modified by SUMO proteins in vitro and in vivo. We showed that SUMOylation of Ki-1/57 occurred on lysines 213, 276, and 336. In transfected cells expressing FLAG-Ki-1/57 wild-type, its paralog FLAG-CGI-55 wild-type, or their non-SUMOylated triple mutants, the number of PML-nuclear bodies (PML-NBs) is reduced compared with the control cells not expressing the constructs. More interestingly, after treating cells with arsenic trioxide (As2O3), the number of PML-NBs is no longer reduced when the non-SUMOylated triple mutant Ki-1/57 is expressed, suggesting that the SUMOylation of Ki-1/57 has a role in the control of As2O3-induced PML-NB formation. A proteome-wide analysis of Ki-1/57 partners in the presence of either SUMO-1 or SUMO-2 suggests that the involvement of Ki-1/57 with the regulation of gene expression is independent of the presence of either SUMO-1 or SUMO-2; however, the presence of SUMO-1 strongly influences the interaction of Ki-1/57 with proteins associated with cellular metabolism, maintenance, and cell cycle.