Biology subjects

Munoz, C.

Publications and source records attributed to Munoz, C..

13 recordsLinked to original sources

bioRxiv2026

An Improved Manufacturing Method for Infusible Extracellular Matrix Materials to Enable Efficient Scale-Up, Improved Efficacy, and Clinical Translation

Decellularized extracellular matrix (ECM) materials are a popular choice for tissue engineering and regenerative medicine applications due to their multifaceted bioactive capabilities arising from their heterogenous composition. For minimally invasive delivery, infusible ECM (iECM) was developed through fractionation of digested decellularized ECM, allowing the material to be safely delivered intravascularly. iECM localizes to permeable vasculature in inflamed tissues and exerts immunomodulatory and pro-reparative effects with proof-of-concept already demonstrated in multiple preclinical models including myocardial infarction (MI) and multiple organ dysfunction syndrome (MODS). However, one major limitation of iECM is the steps required for manufacturing, involving centrifugation, dialysis/lyophilization, and filtration (C-D-F). These steps limit manufacturing output and iECM concentration, and require significant human handling, limiting compliance with current good manufacturing practices (cGMP). To overcome these challenges, we developed a method for manufacturing iECM that utilizes depth filtration and tangential flow filtration (DF-TFF), which reduces manufacturing time, allows for increased iECM concentration, and reduces human manipulation of material, improving translatability and scalability of iECM materials. Based on multiple material characterization methods, we determined that iECM made with DF-TFF was comparable to iECM made with C-D-F. By increasing iECM concentration through this manufacturing method, we demonstrate a dose dependent response in an acute MI porcine model and a mouse MODS model. Finally, DF-TFF enabled timely production of iECM from alternative tissue sources. Altogether, DF-TFF allows for improvements in production time, scale-up, cGMP compliance, and increased dose through higher concentration, paving the way for future clinical translation as well new preclinical studies.

bioengineering↗

bioRxiv2026

Exposure to the antimicrobial peptides LL-37 and ATRA-1 induces a lipidome response in Staphylococcus aureus that alters membrane biophysical properties

Staphylococcus aureus (S. aureus) is an opportunistic pathogen that is a global health concern for its ability to cause a wide spectrum of clinical infections. Due to the emergence of resistance to commonly used antibiotics, there has been interest in exploring the use of antimicrobial peptides to treat S. aureus infections. However, changes in the lipid composition of the lipid bilayer membrane can alter the activity of peptides, and S. aureus is able to induce variations in lipid composition in response to environmental stress. Here, we explore how the main lipid components in S. aureus are altered when exposed to LL-37, a human cathelicidin involved in primary immune response, and ATRA-1, a short antimicrobial peptide derived from the snake Naja atra venom. A lipidomic study is conducted through HPLC-MS-MS (LC-ESI-MS/MS) to quantify phosphatidylglycerol, cardiolipin, lysyl-phosphatidylglycerol, monogalacto- and digalacto-diacylglycerol, and carotenoids. In addition, menaquinones, responsible for electron transport during oxidative phosphorylation, were also quantified. Biophysical properties such as membrane electric surface potential and lipid packing were assessed. We find that lipid adaptation is specific to the type of antimicrobial peptide, where ATRA-1 mainly induces changes in the electric surface potential through variations in Lysyl-PG, while exposure to LL-37 changes carotenoid levels, inducing an increase in membrane rigidity as measured by FTIR. In addition, both peptides induce a reduction in menaquinone and DGDG levels. These findings highlight the role of membrane lipid remodeling as a peptide-specific response mechanism in S. aureus, with implications for the development of AMP-based therapies. HighlightsO_LIStaphylococcus aureus responds through shifts in lipid composition and membrane biophysical properties to exposure to the antimicrobial peptides LL-37 and ATRA-1. C_LIO_LIBoth LL-37 and ATRA-1 lead to shifts in the glycolipids MGDG and DGDG; two lipids involved in regulating negative membrane curvature stress and responsible for shifting resistance to antimicrobial peptide activity in Staphylococcus aureus. C_LIO_LILL-37 treatment leads to an overall reduction in carotenoid content in Staphylococcus aureus, including the carotenoid end-product staphyloxanthin and the precursor 4,4-diaponeurosporenoic acid. Both lipids regulate membrane biophysical properties and protect Staphylococcus aureus from oxidative stress. C_LIO_LIBoth LL-37 and ATRA-1 lead to a reduction in menaquinone levels, which are involved in the electron transport chain during oxidative phosphorylation. Reduction in these menaquinones have been associated to the formation of small colony variants that are often observed in chronic Staphylococcus aureus infections. C_LI

biophysics↗

bioRxiv2026

Regular parental exercise before mating influences offspring lower adiposity associated to hypothalamic neurodevelopmental changes

Physical inactivity is highly prevalent worldwide and affects not only individual health but also the health of future generations. However, the impact of parental physical activity, limited to the pre-mating period, on offspring body weight and composition remains poorly understood. Using a voluntary wheel running approach in mice, we uncovered that post-weaning offspring body weight and composition changes are modulated by the combined effects of pre-mating parental exercise and parental age. Notably, during lactation, pre-mating parental exercise reduced offspring visceral and subcutaneous adiposity, shortened tibia length in female offspring, and influenced offspring transcriptomic profiles of the hypothalamus, the central region regulating body weight and energy balance. These results highlight that regular pre-mating parental exercise may induce offspring neurodevelopmental changes. Although pre-mating exercise minimally impacted the expression of lactation-related genes in maternal subcutaneous fat, as well as breastmilk nutritional composition and miRNA content, these modest miRNA changes may nonetheless influence offspring hypothalamic regulation. Together, these data provide a comprehensive understanding of how parental age and pre-mating exercise impact post-weaning offspring body weight and composition and offer deeper insights into how regular pre-mating parental exercise influences offspring physiology during lactation.

neuroscience↗

bioRxiv2024

Inbreeding and gallbladder cancer risk: Homozygosity associations adjusted for indigenous American ancestry, BMI and genetic risk of gallstone disease

Latin Americans have a rich genetic make-up that translates into heterogeneous fractions of the autosomal genome in runs of homozygosity (FROH), and heterogeneous types and proportions of indigenous American ancestry. While autozygosity has been linked to several human diseases, very little is known about the relationship between inbreeding, genetic ancestry and cancer risk in Latin Americans. Chile has one of the highest incidences of gallbladder cancer (GBC) in the world, and here we investigated the association between inbreeding, GBC, gallstone disease (GSD) and body mass index (BMI) in 4029 genetically admixed Chileans. We calculated individual FROH above 1.5 Mb and weighted polygenic risk scores for GSD, and applied multiple logistic regression to assess the association between homozygosity and GBC risk. We found that homozygosity was due to a heterogeneous mixture of genetic drift and consanguinity in the study population. Although we found no association between homozygosity and overall GBC risk, we detected interactions between FROH and sex, age, and genetic risk of GSD on GBC risk. Specifically, the increase in GBC risk per 1% FROH was 19% in men (P-value = 0.002), 30% in those under 60 years of age (P-value = 0.001), and 12% in those with a genetic risk of GSD above the median (P-value = 0.01). The present study highlights the complex interplay between inbreeding, genetic ancestry and genetic risk of GSD in the development of GBC. The applied methodology and our findings underscore the importance of considering the population-specific genetic architecture, along with sex- and age specific-effects, when investigating the genetic basis of complex traits in Latin Americans.

genetics↗

bioRxiv2023

Diploid genome assembly of the Malbec grapevine cultivar enables haplotype-aware analysis of transcriptomic differences underlying clonal phenotypic variation

1.To preserve their varietal attributes, established grapevine cultivars (Vitis vinifera L. ssp. vinifera) must be clonally propagated, due to their highly heterozygous genomes. Malbec is a France-originated cultivar appreciated for producing high-quality wines, and is the offspring of cultivars Prunelard and Magdeleine Noire des Charentes. Here, we have built a diploid genome assembly of Malbec, after trio binning of PacBio long reads into the two haploid complements inherited from either parent. After haplotype-aware deduplication and corrections, complete assemblies for the two haplophases were obtained with very low haplotype switch-error rate (<0.025). The haplophases alignment identified >25% of polymorphic regions. Gene annotation including RNA-seq transcriptome assembly and ab initio prediction evidence resulted in similar gene model numbers for both haplophases. The annotated diploid assembly was exploited in the transcriptomic comparison of four clonal accessions of Malbec that exhibited variation in berry composition traits. Analysis of the ripening pericarp transcriptome using either haplophases as reference yielded similar results, although some differences were observed. Particularly, among the differentially expressed genes identified only with the Magdeleine-inherited haplotype as reference, we observed an over-representation of hypothetically hemizygous genes. The higher berry anthocyanin content of clonal accession 595 was associated with increased abscisic acid responses, possibly leading to the observed overexpression of phenylpropanoid metabolism genes and deregulation of genes associated to abiotic stress response. Overall, the results highlight the importance of producing diploid assemblies to fully represent the genomic diversity of highly heterozygous woody crop cultivars and to unveil the molecular bases of clonal phenotypic variation.

genomics↗

bioRxiv2023

Applying the area fraction fractionator (AFF) probe for total volume estimations of somatic, dendritic and axonal domains of the nigrostriatal dopaminergic system in a murine model

Using the nigrostriatal dopaminergic system as a case example, we describe a protocol based on Cavalieris principle to estimate the total volume of its somatic, nuclear, dendritic and axonal domains in the adult mouse. This protocol requires serial section analysis, a confocal laser scanning microscope (CLSM), and a stereological software combining the serial section manager (SSM) tool and the area fraction fractionator (AFF) probe. The protocol consists of the following steps: 1) systematic random sampling (SRS) of sites across sections for relevant regions of interest (ROI), which in this study included the substantia nigra pars compacta (SNc) and pars reticulata (SNr), the nigrostriatal tract, and the caudate-putamen complex (CP), 2) high resolution image acquisition of all SRS sites within and across sections, 3) loading of images on the previously defined SRS sites, 4) marking of all cellular structures of interest (cSOI) in the images, including perikarya and cell nuclei, dendrites, axonal segments and varicosities, using Cavalieris point-counting grids, and 5) estimation of cSOI total volume using the estimated area of each cSOI in every brain section, and the distance between sections. The added volume for all cSOI comprising the nigrostriatal dopaminergic system, in this murine model is around 0.37 mm3, with approximately 5% corresponding to perikarya and cell nuclei, 10% to neuropil/dendrites in substantia nigra, and 85% to axonal segments and varicosities within the CP. The use of a simple quantitative approach to assess the global state of a system may allow quantification of compartment-specific changes that may accompany neurodegenerative processes.

neuroscience↗

bioRxiv2022

Buforin II-Escherichia coli's DNA interactome: Detailed biophysical characterization revealed nanoscale complexes likely formed by DNA supercoiling

Antimicrobial peptides (AMPs) have emerged as exciting alternatives to the alarming increase of multiresistant bacteria due to their high activity against them through mechanisms that are thought to largely avoid resistance in the long term. Buforin II (BUFII) is an antibacterial peptide hypothesized to kill bacteria by crossing their membranes to interact with intracellular molecules and interrupt key processes for survival. In particular, interactions with DNA have been considered crucial for triggering cell death mechanisms. However, such interactions are still unknown, and thus far, no reports are available describing BUFII-DNA complexes. Here, we describe a complete biophysical study of the interaction between BUFII and Escherichia coli gDNA via spectrofluorimetric, spectroscopic, and microscopic techniques, complemented with whole-genome sequencing. The E. colis DNA-BUFII interactome was isolated by an in vitro pull-down method aided by BUFII-magnetite nanobioconjugates. Our results demonstrated that DNA-BUFII formed round-shape nanoscale complexes by strong electrostatic interactions, likely occurring nonspecifically throughout the entire bacterial genome. Further sequencing of the isolated DNA fragments corroborated this notion and led to hypothesize that BUFII is possibly responsible for inducing DNAs supercoiling. Other evidence for this idea was provided by the significant DNA conformational changes observed upon interaction with BUFII. Even though the evidence found fails to describe the complete action mechanism of BUFII in vivo, our findings pave the way to engineer DNA-peptide supramolecular complexes very precisely, which might find application in the field of gene therapy delivery.

biophysics↗

bioRxiv2022

Cigarette smoke induces pulmonary arterial dysfunction through an imbalance in the guanylyl cyclase redox status.

Chronic obstructive pulmonary disease (COPD), whose main risk factor is cigarette smoking (CS), is one of the most common diseases globally. Many COPD patients also develop pulmonary hypertension (PH), a severe complication that leads to premature death. Evidence suggests reactive oxygen species (ROS) involvement in COPD and PH, especially regarding pulmonary artery smooth muscle cells (PASMC) dysfunction. However, the effects of CS on the pulmonary vasculature are not completely understood. Herein we provide evidence on the effects of CS extract (CSE) exposure on PASMC regarding ROS production, antioxidant response and its consequences on vascular tone dysregulation. Our results indicate that CSE exposure promotes mitochondrial fission, mitochondrial membrane depolarization and increased mitochondrial superoxide levels. However, the increase in superoxide did not parallel a counterbalancing antioxidant response in human pulmonary artery (PA) cells. Interestingly, the mitochondrial superoxide chelator mitoTEMPO reduced mitochondrial fission and membrane potential depolarization caused by CSE. As we have previously shown, CSE reduces PA vasoconstriction and vasodilation. In this respect, mitoTEMPO prevented the impaired nitric oxide-mediated vasodilation, while vasoconstriction remained reduced. Finally, we observed a CSE-driven downregulation of the Cyb5R3 enzyme, which prevents soluble guanylyl cyclase oxidation in PASMC. This might explain the CSE-mediated decrease in PA vasodilation. These results provide evidence that there might be a connection between mitochondrial ROS and altered vasodilation responses in PH secondary to COPD, and strongly support the potential of antioxidant strategies specifically targeting mitochondria as a new therapy for these diseases. Graphical abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

cell biology↗

bioRxiv2021

Microbiota depletion promotes human rotavirus replication in an adult mouse model

The study of human rotavirus (RV) infectivity in vivo has been limited by the lack of small animal models able to efficiently replicate the principal human RV genotypes. In recent years, intestinal microbiota-virus-host interaction has emerged as a key factor in mediating enteric virus pathogenicity. With the aim of developing an adult mouse infection model for RV we performed faecal microbiota transplant (FMT) with healthy infants as donors in antibiotic-treated mice. Contrarily to control mice, in the FMT group, but also in antibiotic-treated mice without FMT, challenge with the human RV G1P[8] genotype, Wa strain (RVwa), resulted in viral shedding in the faeces for 6 days. RV titres in faeces were also significantly higher in antibiotic-treated animals with or without FMT. This excluded the hypothesis that donors microbiota promoted infection. Antibiotic treatment followed by self-FMT resulted in incomplete re-establishment of mouse microbiota which partially restored suppression of RVwa infection. Microbial composition analysis revealed profound changes in the intestinal microbiota of antibiotic-treated animals, whereas some bacterial groups, including members of Lactobacillus, Bilophila, Mucispirillum and Oscillospira, reappeared after self-FMT. In antibiotic-treated and FMT animals, differences were observed in gene expression of immune mediators such as IL10, TNF- and IFN{gamma} and the fucosyltransferase FUT2, responsible for H-type antigen synthesis in the small intestine. Collectively, our results suggest that antibiotic-induced microbiota depletion eradicates the microbial taxa that restrict human RV infectivity in mice. Viral permissiveness could involve changes in the innate immune system at the small intestine and alterations in the bacteria population that potentially interact with RV, creating a favourable environment for human RV replication in mice.

microbiology↗

bioRxiv2020

Clonal propagation history shapes the intra-cultivar genetic diversity in Malbec grapevines

Grapevine (Vitis vinifera L.) cultivars are clonally propagated to preserve their varietal attributes. However, novel genetic variation still accumulates due to somatic mutations. Aiming to study the potential impact of clonal propagation history on grapevines intra-cultivar genetic diversity, we have focused on Malbec. This cultivar is appreciated for red wines elaboration, it was originated in Southwestern France and introduced into Argentina during the 1850s. Here, we generated whole-genome resequencing data for four Malbec clones with different historical backgrounds. A stringent variant calling procedure was established to identify reliable clonal polymorphisms, additionally corroborated by Sanger sequencing. This analysis retrieved 941 single nucleotide variants (SNVs), occurring among the analyzed clones. Based on a set of validated SNVs, a genotyping experiment was custom-designed to survey Malbec genetic diversity. We successfully genotyped 214 samples and identified 14 different clonal genotypes, that clustered into two genetically divergent groups. Group-Ar was driven by clones with a long history of clonal propagation in Argentina, while Group-Fr was driven by clones that have longer remained in Europe. Findings show the ability of such approaches for clonal genotypes identification in grapevines. In particular, we provide evidence on how human actions may have shaped Malbec extant genetic diversity pattern.

genomics↗

bioRxiv2020

An image J plugin for the high throughput image analysis of in vitro scratch wound healing assays

In vitro scratch wound healing assay, a simple and low-cost technique that works along with other image analysis tools, is one of the most widely used 2D methods to determine the cellular migration and proliferation in processes such as regeneration and disease. There are open-source programs such as imageJ to analyze images of in vitro scratch wound healing assays, but these tools require manual tuning of various parameters, which is time-consuming and limits image throughput. For that reason, we developed an optimized plugin for imageJ to automatically recognize the wound healing size, correct the average wound width by considering its inclination, and quantify other important parameters such as: area, wound area fraction, average wound width, and width deviation of the wound images obtained from a scratch/ wound healing assay. Our plugin is easy to install and can be used with different operating systems. It can be adapted to analyze both individual images and stacks. Additionally, it allows the analysis of images obtained from bright field, phase contrast, and fluorescence microscopes. In conclusion, this new imageJ plugin is a robust tool to automatically standardize and facilitate quantification of different in vitro wound parameters with high accuracy compared with other tools and manual identification.

bioengineering↗

bioRxiv2019

HIGH PREVALENCE OF STRONGYLOIDIASIS IN SPAIN: A HOSPITAL-BASED STUDY

Strongyloidiasis is a prevailing helminth infection ubiquitous in tropical and subtropical areas. However, prevalence data are scarce in migrant populations. This study aims at evaluating the prevalence of S. stercoralis at hospital level in migrant populations or long term travellers being attended in out-patient and in-patient units as part of a systematic screening implemented in 6 Spanish hospitals. A cross-sectional study was conducted and systematic screening for S. stercoralis infection using serological tests was offered to all eligible participants. The overall seroprevalence of S. stercoralis was 9.04% (95% confidence interval [95%CI] 7.76 -10.31). The seroprevalence of people with a risk of infection acquired in Africa and Latin America was 9.35% (95%CI 7.01-11.69), 9.22% (7.5-10.93), respectively. The number of individuals coming from Asian countries was significantly smaller and the overall prevalence in these countries was 2.9% (95%CI -0.3; -6.2). There was only one case (1/14 (7.14%) from an individual from East European countries. The seroprevalence in units attending potentially immunosuppressed patients was significantly lower (5.64%) compared with the seroprevalence in other units of the hospital (10.20%) or Tropical diseases units (13.33%) (p<0.001). Conclusions: We report a hospital-based systematic screening of strongyloidiasis with a seroprevalence of almost 10% in a mobile population coming from endemic areas suggesting the need of implementing strongyloidiasis screening in hospitalized patients coming from endemic areas, particularly if they are at risk of immunosuppression. Author summaryStrongyloidiasis is an infection caused by the helminth Strongyloides stercoralis which is ubiquitous in tropical and subtropical areas. In the rest of the countries, it is also frequent in migrants coming from tropical and subtropical areas. The disease is more severe when an infected subject has an impaired immune system. Within this study we have evaluated the prevalence of this infection in people being attended in six Spanish hospitals. The prevalence was around 9%, being higher in Africa and Latin America compared with other regions. In addition, the prevalence in patients with an impaired immune system (immunosuppression) was lower compared with people non suffering immunosuppression. These results suggest that the prevalence of strongyloidiasis is quite high among migrants living in Spain and that a screening programme should be designed, particularly in immunosuppressed patients that are at more risk of suffering severe complications of the infection.

microbiology↗

bioRxiv2019

Frequency of tuberculosis in Farm Workers Exposed to dairy and beef livestock in Colombia

The objective of this study was to determine the frequency of tuberculosis (TB) in workers from dairy and beef livestock farms in the northern part of Colombia. Tuberculin skin test and an interferon-gamma release assay (IGRA) were used for diagnosis of latent tuberculosis; sputum samples were taken from respiratory symptomatic subjects, microbiological and molecular tests were done for diagnosis of active TB. Absolute frequencies, percentages, and crude prevalence ratios were calculated, and a robust Poisson Model with adjustment by municipality was made. In 674 farm workers, latent TB frequency was 35.8%. Variables such as having had pulmonary TB (PR 2.82, 95% CI 1.90 - 4.17), having been in contact with people with active TB (PR 1.57, 95% CI 1.24 - 1.98), and having performed some undergraduate or postgraduate study (PR 1.6, 95% CI 1.03 - 2.49), were significantly associated with latent TB. No active tuberculosis disease was confirmed in symptomatic respiratory patients. The exposure level to cattle was not significantly associated with latent TB infection. In conclusion, in the studied population exposure to cattle was not a risk factor for TB, other factors commonly found in general population exposed to human TB were demonstrated.\n\nAuthor summaryZoonotic TB is a disease caused by the transmission of the M. bovis bacteria that is part of the Mycobacterium tuberculosis Complex, through contact with cattle to humans, by the consumption of unpasteurized dairy products from infected animals or by inhalation of aerosols exhaled by sick animals.\n\nThis study investigated the frequency of TB in human population related to cattle, in order to determine if there were risk factors related to TB infection or disease. Finding that there was no significant relationship between being exposed to cattle and having latent TB. However, the results of this study together with other research reported in the literature suggest that research on zoonotic and bovine TB should be continued, especially about epidemiology, diagnostic methods, health systems and interventions coordinated with veterinary services.

microbiology↗