Innovative multiple nanoemulsion (W/O/W) based on Chilean honeybee pollen improves their permeability, antioxidant and antibacterial activity

Beehive derivatives, including honeybee pollen (HBP), have been extensively studied for their beneficial health properties and potential therapeutic use. Its high polyphenol content gives it excellent antioxidant and antibacterial properties. Today its use is limited due to poor organoleptic properties, low solubility, stability, and permeability under physiological conditions. A novel edible multiple W/O/W nanoemulsion (BP-MNE) to encapsulate the HBP extract was designed and optimized to overcome these limitations. The new BP-MNE has a small size (∼100 nm), a zeta potential greater than +30 mV, and efficiently encapsulated phenolic compounds (∼82%). BP-MNE stability was measured under simulated physiological conditions and storage conditions (4 months); in both cases, stability was promoted. The formulation's antioxidant and antibacterial (Streptococcus pyogenes) activity was analyzed, obtaining a higher effect than the non-encapsulated compounds in both cases. In vitro permeability was tested, observing a high permeability of the phenolic compounds when they are nanoencapsulated. With these results, we propose our BP-MNE as an innovative solution to encapsulate complex matrices, such as HBP extract, as a platform to develop functional foods.

Brain-region specific responses of astrocytes to an in vitro injury and neurotrophins

Astrocytes are a heterogeneous population of glial cells that react to brain insults through a process referred to as astrogliosis. Reactive astrocytes are characterized by an increase in proliferation, size, migration to the injured zone and release of a plethora of chemical mediators such as NGF and BDNF. The aim of this study was to determine whether there are brain region-associated responses of astrocytes to an injury and to the neurotrophins NGF and BDNF. We used the scratch injury model to study the closure of a wound inflicted on a monolayer of astrocytes obtained from cortex, hippocampus or striatum. Our results indicate that the response of astrocytes to a mechanical lesion differ according to brain regions. Astrocytes from the striatum proliferate and repopulate the injury site more rapidly than astrocytes from cortex or hippocampus. We found that the scratch injury induced the upregulation of neurotrophin receptor p75NTR and TrkB.t in astrocytes from all brain regions studied. When astrocytes from all regions were treated with NGF, the neurotrophin induced migration of the astrocytes (assessed in Boyden chambers) and induced wound closure but did not affect proliferation. In contrast, BDNF induced wound closure but only in astrocytes from striatum. Our overall findings show the heterogeneity in astrocyte functions based on their brain region of origin, and how this functional diversity may determine their responses to an injury and to neurotrophins.

Propolis from Chilean Matorral Hives

Viscidone (0.5%), vanillin, 3',4'-(methylendioxy)acetophenone, 3-ethoxy-4-methoxybenz-aldehyde, cinnamic acid, 3-methoxy-4-hydroxymethyl ester were isolated from propolis of hives from Cuncumen. This is the first report on propolis composition of an arid and a Mediterranean type climate area.

Mutation screening of spastin, atlastin, and REEP1 in hereditary spastic paraplegia

Hereditary spastic paraplegia (HSP) comprises a group of clinically and genetically heterogeneous diseases that affect the upper motor neurons and their axonal projections. Over 40 chromosomal loci have been identified for autosomal dominant, recessive, and X-linked HSP. Mutations in the genes atlastin, spastin and REEP1 are estimated to account for up to 50% of autosomal-dominant HSP and currently guide the molecular diagnosis of HSP. Here, we report the mutation screening results of 120 HSP patients from North America for spastin, atlastin, and REEP1, with the latter one partially reported previously. We identified mutations in 36.7% of all tested HSP patients and describe 20 novel changes in spastin and atlastin. Our results add to a growing number of HSP disease-associated variants and confirm the high prevalence of atlastin, spastin, and REEP1 mutations in the HSP patient population.

Immunotherapy as an adjuvant therapy in the management of advanced, surgically resected, melanoma

Metastatic melanoma continues to be one of the most devastating of all cancers. It is a heterogeneous solid tumor whose treatment is challenging and difficult. It afflicts thousands of otherwise healthy patients annually, and clinicians have yet to discover an effective treatment for locally advanced disease. Over the years, much attention has been devoted to the development of an effective adjuvant treatment for patients with resected melanoma who remain at high risk for recurrence. The new advances in the understanding of melanoma's microenvironment and the complexity of its disease process, makes it clear that the treatment approach to this disease needs to be multi-directional. Numerous studies have tested various immunotherapeutic strategies in the treatment of advanced melanoma, in particular. These strategies include melanoma vaccines, interferon-alpha, interleukin-2 (IL-2), and dendritic cell vaccines. The Dr. Wallack's Surgery Research Laboratory has been studying melanoma vaccines for the past three decades. The first generation melanoma vaccine proposed by the Laboratory showed promising results in a subset of patients. Recently, the same Laboratory has produced a second generation melanoma vaccine (DC-Melvac) that consists of five human melanoma cell lines, a recombinant vaccinia virus that encodes for IL-2, as well as dendritic cells that have been programmed to recognize certain melanoma associated antigens. DC-MelVac was recently approved by the Food and Drug Administration for its use in Phase I clinical trials. These trials are expected to be underway in the near future. The ensuing review discusses many of the immunotherapeutic strategies that have been studied in the treatment of melanoma, including DC-MelVac.

Inhibition of Mycobacterium tuberculosis growth by saringosterol from Lessonia nigrescens

Assay-guided fractionation of an antitubercular extract obtained from Lessonia nigrescens yielded the phytosterol saringosterol as its active component. No appreciable toxicity against Vero cells was observed for this compound. Saringosterol was also synthesized by oxidation of fucosterol. The MIC values for antitubercular activity of saringosterol and its 24S and 24R epimers were determined as 0.25, 1, and 0.125 microg/mL.

Iridoids from Stachys grandidentata (Labiatae)

Monomelittoside, melittoside, 8-acetyl-harpagide, harpagide, ajugol, 5-desoxy-harpagide, 5-desoxy-8-acetylharpagide and catalpol were isolated from the aerial parts of S. grandidentata.

Phenolic compounds of propolis from Central Chilean matorral

Pinocembrin, acacetin, galanguin, izalpin, kaempferide, prenyletin and diarytheptane were isolated from propolis from Central Chile.

Two novel flavanones from Greigia sphacelata

As part of our continuing phytochemical investigations of plants from arid environments in Chile, the aerial parts of Greigia sphacelata were examined. Two novel flavanones, 5,7,3'-trihydroxy-6, 4',5'-trimethoxyflavanone (1) and 5,3'-dihydroxy-6,7,4', 5'-tetramethoxyflavanone (2), as well as eight known compounds-1, 3-O-di-trans-p-coumaroylglycerol (3), 1-O-trans-p-coumaroylglycerol (4), a mixture of 1-(omega-feruloyldocosanoyl)glycerol (5) and 1-(omega-feruloyltetracosanoyl)glycerol (6), trans-ferulic acid 22-hydroxydocosanoic acid ester (7), arborinone (8), arborinol (9), and isoarborinol (10)-were isolated.

Synthesis and biological studies of glycosyl dopamine derivatives as potential antiparkinsonian agents

A new approach to deliver dopamine into the central nervous system, based on the use of D-glucose as transportable agent, has been studied. Glycosyl dopamine derivatives bearing the sugar moiety linked to either the amino group or the catechol ring of dopamine through amide, ester or glycosidic bonds were synthesised as potential antiparkinsonian agents. Studies on the binding to dopamine D2 receptor, in vitro stability, and locomotive effect in mice of the synthetic glycoconjugates are reported.

Flavonoids and terpenoids from Luma gayana (Barn.) Burret

The flavonoids 5-hydroxy-7-methoxyflavanone, 6,8-dimethyl-5,7-dihydroxyflavanone and 2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone, a mixture of alkyl esters of p-coumaric acid, the triterpenoids oleanolic acid and maslinic acid, the monoterpenoid 1 alpha,2 beta,4 beta-trihydroxy-p-menthane, the sesquiterpenoid clovandiol and beta-sitosterol were isolated from the aerial parts of Luma gayana (Barn.) Burret. This is the first report on the chemistry of this species.

Pentacyclic triterpenes from Chuquiraga ulicina

Four taraxastane triterpenes, 3 beta-acetoxy-6 beta-hydroxytaraxasta-20-ene, 6 beta-hydroxytaraxasta-20-en-3-one, 6 beta-hydroxytaraxasta-20-ene 3 beta-palmitate and 3 beta,6 beta-dihydroxytaraxasta-20-ene were isolated from the dichloromethane-methanol extract of Chuquiraga ulicina ssp. ulicina together with the known triterpenes lupeol, lupenyl acetate, lupenone, friedelinol, 3 beta-acetoxy-30-nor-lupan-20-one, and 30-nor-lupan-3 beta-ol-20-one.

Antitubercular activity of pentacyclic triterpenoids from plants of Argentina and Chile

Screening of plants from South America for antitubercular activity and subsequent assay-guided fractionation resulted in the isolation and characterization of several pentacyclic triterpenoids. The MIC values of 22 triterpenoids were determined using the radiorespiratory BACTEC assay and range from 8 microM to above 128 microM. The structure-activity relationships are discussed.

Antibacterial diterpenoid acids from Azorella compacta

The two novel diterpenoid acids mulin-12,14-dien-11-on-20-oic acid (1) and mulin-12-ene-11,14-dion-20-oic acid (2) have been isolated from Azorella compacta. Their structures have been elucidated by 1D and 2D NMR methods. In contrast to the closely related known mulinolic acid (3) and its dehydration product (4) these new natural products have been shown to exhibit antimicrobial activity.

Phytochemical, morphological, and biological investigations of propolis from Central Chile

Propolis from central Chile was investigated for its plant origin by microscopical analysis of pollen grains and leaf fragments found in the sample. The pollen grains that appear with significant higher frequency in the sample corresponded to four native and two introduced species, whereas leaf fragments corresponded to four native species. Seventeen phenolic compounds that belong to the phenylpropane, benzaldehyde, dihydrobenzofuran, or benzopyran classes, were isolated from an organic extract that was found to have a moderate growth inhibitory activity against Mycobacterium avium, M. tuberculosis, and two strains of Staphylococcus aureus. The components responsible for activity were determined.

Diterpenoids from Baccharis pingraea

From the aerial parts of Baccharis pingraea the known furolabdane, angeloyl-gutierrezianolic acid (1); two novel diterpenoids, furolabda-6,8-dien-17-oic acid (2) and furolabd-7-en-17-oic acid (3); and the known linear diterpenoid, (10E)-centipedic acid (4), were isolated. LC/MS suggested the presence of gutierrezianolic acid (5). The structures of the new compounds were elucidated by 1D and 2D NMR methods.

A new antitubercular mulinane diterpenoid from Azorella madreporica Clos

Bioactivity-guided fractionation of the petroleum ether extract of Azorella madreporica Clos has led to the isolation of the novel, antitubercular mulinane diterpenoid 1. The structure has been elucidated on the basis of its 1D and 2D NMR spectra and by comparison with mulinolic acid 2 and a dehydration product 3 obtained from 1. The MIC of 1 for growth inhibition of the H37Rv strain of Mycobacterium tuberculosis was determined as 20 microg/mL. LC-MS and NMR have suggested the presence of this new compound in four other species of Azorella.

Lignans from Chilean propolis

Three new (1, 3, 4) and two known lignans (2 and 5) were isolated from Chilean propolis. Compound 1 was identified as a trimeric coniferyl alcohol acetate and 3 as the diastereomer of the dimeric coniferyl alcohol acetate 2. Compound 4 was identified as a dihydrobenzofuran lignan aldehyde, which was isolated together with the related known acetate 5.

Triterpenoids from Acaena pinnatifida R. et P

Eight urs-12-ene triterpenoids, beta-sitosterol, (+)-catechin, and apigenin 7-O-glucoside were isolated from the leaves of Acaena pinnatifida R. et P. The triterpenoids were characterized as pomolic acid, pomolic acid-3-acetate, tormentic acid, 2-epi-tormentic acid, euscaphic acid, tormentic acid glucoside, niga-ichigoside F1, and niga-ichigoside F2.

[Bioessay with brine Artemia to predict antibacterial and pharmacologic activity]

The Brine Shrimp Test (BST) is a simple and inexpensive method to test cytotoxity, to biodirect phytochemical fractionation of natural products and as a predictor for antitumor and pesticidal activity. In this work, the BST test, an antibacterial test and the rat hippocratic screening test were used on 25 plant extracts and fractions, to evaluate the correlation, if any, between the BST and the others. Preliminary results show that the BST is not a predictor of antibacterial activity nor the hippocratic screening test.