Browsing by Author "Martínez, Jessica"
Now showing 1 - 7 of 7
Results Per Page
Sort Options
Publication Aloe vera peel-derived nanovesicles display anti-inflammatory properties and prevent myofibroblast differentiation(2024) Ramírez, Orlando; Pomareda, Florencia; Olivares, Belén; Huang, Ya-Lin; Zavala, Gabriela; Carrasco, Javiera; Álvarez, Simón; Leiva, Camila; Hidalgo, Valeria; Romo, Pablo; Sánchez, Matías; Vargas, Ayleen; Martínez, Jessica; Aguayo, Sebastian; Schuh, ChristinaBackground: Aloe vera (AV) is a medicinal plant, most known for its beneficial effects on a variety of skin conditions. Its known active compounds include carbohydrates and flavonoids such as quercetin and kaempferol, among others. In the past decade, plant nanovesicles (NVs) have gained considerable interest as interkingdom communicators, presenting an opportunity for clinical standardization of natural products. In this study, we aimed to assess the potential of AVpNVs for the treatment of burn wounds. Methods: AVpNVs were isolated and characterized regarding vesicle yield (nanoparticle tracking analysis) and structure (transmission electron microscopy and atomic force microscopy), as well as their protein content with proteomics. We assessed key characteristics for treating burn wounds in vitro, such as the anti-inflammatory potential in LPS-stimulated macrophages and keratinocytes, and the effect of AVpNVs on myofibroblast differentiation and contraction. Key findings: AVpNVs presented a homogenous NV population, vesicular shape, and NV-associated protein markers. AVpNVs significantly decreased the secretion of pro-inflammatory cytokines TNFα, IL-1β, and IL-6. Furthermore, AVpNVs inhibited myofibroblast differentiation and significantly decreased their contractile potential in collagen matrices. Observed effects were linked to proteins identified in the isolates through proteomics analysis. Conclusion: AVpNVs displayed characteristics as an inflammatory modulator, while simultaneously diminishing myofibroblast differentiation and contraction. Novel strategies for burn wound treatment seek to decrease scarring on a cellular and molecular level in the early stages of wound healing, which makes AVpNVs a promising candidate for future plant-vesicle-based treatments.Publication Antifungal activity of “HO21-F”, a formulation based on Olea europaea plant extract, in honey bees infected with Nosema ceranae(2022) Duguet, Jos!e; Zuñiga, Fabián; Martínez, JessicaNosema ceranae is a microsporidium parasite that silently affects honey bees, causing a disease called nosemosis. This parasite produces resistant spores and germinates in the midgut of honey bees, extrudes a polar tubule that injects an infective sporoplasm in the host cell epithelium, proliferates, and produces intestinal disorders that shorten honey bee lifespan. The rapid extension of this disease has been reported to be widespread among adultbees, and treatments are less effective and counterproductive weakening colonies. This work aimed to evaluatethe antifungal activity of a prototype formulation based on a non-toxic plant extract (HO21-F) against N ceranae. In laboratory, honey bees were infected artificially, kept in cages for 17 days and samples were taken at 7 and 14 days post infection (dpi). At the same time, in field conditions we evaluated the therapeutic effect of HO21-F for 28 days in naturally infected colonies. The effectiveness of the treatment has been demonstrated by a reduction of 83.6 % of the infection levels observed in laboratory conditions at concentrations of 0.5 and 1 g/L without affecting the survival rate. Besides, in-field conditions we reported a reduction of 88 % of the infection level at a concentration of 2.5 g/L, obtaining better antifungal effectiveness in comparison to other commercially available treatments. As a result, we observed that the use of HO21-F led to an increase in population size and honey production, both parameters associated with colony strength. The reported antifungal activity of HO21-F against N. ceranae, with a significant control of spore proliferation in worker bees, suggests the promising commercial application use of this product against nosemosis, and it will encourage new research studies to understand the mechanism of action, whether related to the spore-inhibition effect and/or a stimulating effect in natural response of colonies to counteract the disease.Item Immune-related gene expression in honey bee larva (Apis mellifera) exposed to plant extracts from Humulus lupulus with antimicrobial activity against Paenibacillus larvae(2021) Giménez-Martínez, Pablo; Zuñiga, Fabián; Junges, Celina; Maggi, Matías; Fuselli, Sandra; Martínez, JessicaAmerican foulbrood caused by Paenibacillus larvae brings with it several problems on beekeepers for the use of synthetic antibiotics, likewise led to the appearance of resistant strains and the presence of chemical residues in the commercial products of the hive. In recent years, the use of natural compounds for the control of P. larvae has increased. Herein, we propose to determine the value of the Minimal Inhibitory Concentration (MIC) of a hydroalcoholic extract of Humulus lupulus (hop) leaves of Victoria variety on P. larvae strain, and to evaluate its toxicity and effect on the expression of three genes of the immune system on honey bee larvae. For the extract, the MIC value was 83.79 μg/mL. For larvae, the extract did not show toxicity, on the other hand presented a down-regulation in the gene expression for the three genes evaluated. The results obtained here are a first report on the evaluation in the effect of natural extracts on the expression of genes related to the immune system in bee larvae.Item Matrix solid-phase dispersion associated to gas chromatography forthe assessment in honey bee of a group of pesticides of concern in theapicultural field(2018) Balsebre, Arantza; Báeza, María; Martínez, Jessica; Fuentesa, EdwarA method based on matrix solid-phase dispersion (MSPD) associated to gas chromatography-flame photometric detection (GC-FPD), GC-electron capture detection (GC-ECD) and GC-mass spectrometry (GC–MS) for confirmation purposes, was developed for the determination of a representative group of twelve pesticides in honeybee with particular concern in the apicultural field (fipronil, thiamethoxam, acetamiprid, acrinathrin, metamidophos, dimetoathe, diazinon, chlorpyrifos, methidathion, profenophos, azinphos methyl and coumaphos). Factors influencing the extraction efficiency of MSPD were investigated and optimized through response surface method. The use of octadecylsilyl (C18) sorbent combined with a florisil clean-up and acetonitrile-methanol (99:1) elution was the optimal condition for the extraction of the selected pesticides. Under this condition the recovery of pesticides at the limit of quantification of the method (0.007 to 0.050 μg g−1) ranged from 68 to 102% with RSDs for within-laboratory reproducibility ≤20%. The proposed method was applied to the analysis of honeybees collected in 68 field hives from areas of great apicultural and agricultural development in central Chile. In 65% of these samples eight different pesticides were detected. Pesticides most frequently found were chlorpyrifos (34% of the samples, <0.017–0.067 μg g−1), acrinathrin (32% of the samples, <0.020–0.026 μg g−1) and diazinon (10% of the samples at values <0.015 μg g−1). The incidence of these pesticides in bees can be related to their high employ in central Chile, use to combat the varroosis in hives and hydrophobicity.Publication Nanomaterials Based on Honey and Propolis for Wound Healing—A Mini-Review(2022) Jaldin, Limberg; Silva, Nataly; Martínez, JessicaWound healing is a public health concern worldwide, particularly in chronic wounds due to delayed healing and susceptibility to bacterial infection. Nanomaterials are widely used in wound healing treatments due to their unique properties associated with their size and very large surface-area-to-volume ratio compared to the same material in bulk. The properties of nanomaterials can be expanded and improved upon with the addition of honey and propolis, due to the presence of bioactive molecules such as polyphenols, flavonoids, peptides, and enzymes. These bionanomaterials can act at different stages of wound healing and through different mechanisms, including anti-inflammatory, antimicrobial, antioxidant, collagen synthesis stimulation, cell proliferation, and angiogenic effects. Biomaterials, at the nanoscale, show new alternatives for wound therapy, allowing for targeted and continuous delivery of beekeeping products at the injection site, thus avoiding possible systemic adverse effects. Here, we summarize the most recent therapies for wound healing based on bionanomaterials assisted by honey and propolis, with a focus on in vitro and in vivo studies. We highlight the type, composition (honey, propolis, and polymeric scaffolds), biological, physicochemical/mechanical properties, potential applications and patents related of the last eight years. Furthermore, we discuss the challenges, advantages, disadvantages and stability of different bionanomaterials related to their clinical translation and insight into the investigation and development of new treatments for wound healing.Item Nosema ceranae an emergent pathogen of Apis mellifera in Chile(Springer, 2012) Martínez, Jessica; Leal, Germán; Conget, PauletteThe microsporidian Nosema apis and Nosema ceranae have been associated with colony disorders of Apis mellifera and Apis cerana, respectively. N. apis is endemic in South America. Recently, N. ceranae has been detected in Brazil, Uruguay and Argentina. No report of its presence, distribution and prevalence in Chile is available. Here, we present a real-time PCR-based method that was able to discriminate between N. apis and N. ceranae. The dynamic range of this assay was 100 to 100,000 spores per honeybee. False-negative results were avoided due to the use of ACTIN gene as internal standard. False-positive results were obtained neither in experimentally nor in naturally contaminated samples. Using this method, we screened 240 beehives from the Chilean region where 42% of the total country honey production take places (Región del Biobío). Nosema spp. were detected in the four provinces and in 20 of the 26 communes of the region. Among the samples analysed, 49% were positive for N. ceranae. Their infection level ranged from 200 to more than 100,000 spores per honeybee. N. apis was not detected in this region. Hence, our data show that in Chile N. ceranae is an emergent pathogen that is been replacing N. apis. Also, they support that N. ceranae maybe the actual responsible for nosemosis in A. mellifera in South America.Item Relationship among the minor constituents, antibacterial activity and geographical origin of honey: A multifactor perspective(2020) Cebrero, Gonzalo; Sanhueza, Oscar; Pezoa, Matías; Báez, María E.; Martínez, Jessica; Báez, Mauricio; Fuentes, EdwarSome minor constituents of honey samples were determined through a fluorometric-chemical characterization method and related multifactorially with their antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa and with their geographical origin. Rotated principal component analysis identified five significant components in honey: three related to antibacterial activity and linked to phenolic compounds; Maillard products; proteins; the concentration of H2O2 at 3 and 24 h of incubation; and a tyrosine-containing entity. On the other hand, five constituents (phenolic compounds were the most relevant) allowed the classification of honey samples by geographical origin with 87% certainty. The results showed that phenolic compounds and Maillard products are related to the sustained production of H2O2 over time, which in turn boosts the antibacterial activity of honey. Native flora could promote this capability. The results showed the effect of geographic origin on the content of the analyzed minor constituents of honey, particularly phenolic compounds.