Vascular lysyl oxidase over-expression alters extracellular matrix structure and induces oxidative stress

Lysyl oxidase (LOX) participates in the assembly of collagen and elastin fibres. The impact of vascular LOX over-expression on extracellular matrix (ECM) structure and its contribution to oxidative stress has been analysed. Methods Studies were conducted on mice over-expressing LOX (Tg), specifically in smooth muscle cells (VSMC). Gene expression was assessed by real-time PCR analysis. Sirius Red staining, H 2 O 2 production and NADPH oxidase activity were analysed in different vascular beds. The size and number of fenestra of the internal elastic lamina were determined by confocal microscopy. Results LOX activity was up-regulated in VSMC of transgenic mice compared with cells from control animals. At the same time, transgenic cells deposited more organised elastin fibres and their supernatants induced a stronger collagen assembly in in vitro assays. Vascular collagen cross-linking was also higher in Tg mice, which showed a decrease in the size of fenestrae and an enhanced expression of Fibulin-5. Interestingly, higher H 2 O 2 production and NADPH oxidase activity was detected in the vascular wall from transgenic mice. The H 2 O 2 scavenger catalase attenuated the stronger deposition of mature elastin fibres induced by LOX transgenesis. Conclusions LOX over-expression in VSMC was associated with a change in the structure of collagen and elastin fibres. LOX could constitute a novel source of oxidative stress that might participate in elastin changes and contribute to vascular remodellingLa lisil oxidasa (LOX) contribuye al ensamblaje de las fibras de colágeno y elastina de la matriz extracelular (MEC). Hemos determinado las consecuencias de la sobre-expresión vascular de LOX sobre la estructura de la MEC y su contribución al estrés oxidativo. Métodos: Los estudios se desarrollaron en ratones que sobre-expresan la LOX (Tg) específicamente en células musculares lisas vasculares (CMLV). Se realizaron análisis por PCR a tiempo real, tinción de rojo sirio, producción de H2O2 y actividad NADPH oxidasa. Se caracterizaron las fenestras de la lámina elástica interna mediante microscopía confocal. Resultados: Las CMLV de ratones transgénicos presentaron niveles de actividad LOX superiores a los de animales control. En consonancia, las células transgénicas depositaron más fibras de elastina organizada y sus sobrenadantes indujeron un mayor ensamblaje de colágeno en ensayos in vitro. El nivel de colágeno maduro fue superior en la pared vascular de ratones Tg, que presentaban un menor área de las fenestras y un aumento de la expresión de la Fibulina-5. La producción vascular de H2O2 y la actividad NADPH oxidasa fueron superiores en los ratones transgénicos. La incubación de CMLV con catalasa atenuó el incremento en la deposición de fibras de elastina madura inducido por la transgénesis de LOX. Conclusiones: La sobre-expresión de la LOX en CMLV se asocia a una alteración de la estructura vascular del colágeno y la elastina. La LOX podría constituir una nueva fuente de estrés oxidativo que participaría en la alteración estructural de la MEC y podría contribuir al remodelado vascularEste estudio se ha financiado por la Fundación Española de Aterosclerosis, Beca SEA/FEA de Investigación básica 2016 y por el Ministerio de Economía y Competitividad (MINECO)-Instituto de Salud Carlos III (ISCIII) [proyectos PI15/01016, PI13/01488, SAF2012-36400; SAF2015-64767-R]. El CIBER de Enfermedades Cardiovasculares es una iniciativa del ISCIII. AMB recibió una ayuda del programa Ramón y Cajal (RYC-2010-06473). El estudio ha sido cofinanciado por el Fondo Europeo de Desarrollo Regional (FEDER

Retinal pigment epithelium degeneration caused by aggregation of PRPF31 and the role of HSP70 family of proteins

Background Mutations in pre-mRNA splicing factor PRPF31 can lead to retinitis pigmentosa (RP). Although the exact disease mechanism remains unknown, it has been hypothesized that haploinsufficiency might be involved in the pathophysiology of the disease. Methods In this study, we have analyzed a mouse model containing the p.A216P mutation in Prpf31 gene. Results We found that mutant Prpf31 protein produces cytoplasmic aggregates in the retinal pigment epithelium and decreasing the protein levels of this splicing factor in the nucleus. Additionally, normal protein was recruited in insoluble aggregates when the mutant protein was overexpressed in vitro. In response to protein aggregation, Hspa4l is overexpressed. This member of the HSP70 family of chaperones might contribute to the correct folding and solubilization of the mutant protein, allowing its translocation to the nucleus. Conclusions Our data suggests that a mechanism haploinsufficiency and dominant-negative is involved in retinal degeneration due to mutations in PRPF31. HSP70 over-expression might be a new therapeutic target for the treatment of retinal degeneration due to PRPF31 mutations.This project has been financed through a) The ISCIII (Miguel Servet-I, 2015), co-financed by the European Regional Development Fund (ERDF), No CP15/00071. b) The European Union’s Horizon 2020 research and innovation program, under grant agreement No 634479. c) Regional Ministry of Economy, Innovation and Science of the Junta de Andalucía, No P09-CTS-04967.info:eu-repo/semantics/publishedVersio

Reduced Binding of the Endolysin LysTP712 to Lactococcus lactis ΔftsH Contributes to Phage Resistance

Absence of the membrane protease FtsH in Lactococcus lactis hinders release of the bacteriophage TP712. In this work we have analyzed the mechanism responsible for the non-lytic phenotype of L. lactis ΔftsH after phage infection. The lytic cassette of TP712 contains a putative antiholin–pinholin system and a modular endolysin (LysTP712). Inducible expression of the holin gene demonstrated the presence of a dual start motif which is functional in both wildtype and L. lactis ΔftsH cells. Moreover, simulating holin activity with ionophores accelerated lysis of wildtype cells but not L. lactis ΔftsH cells, suggesting inhibition of the endolysin rather than a role of FtsH in holin activation. However, zymograms revealed the synthesis of an active endolysin in both wildtype and L. lactis ΔftsH TP712 lysogens. A reporter protein was generated by fusing the cell wall binding domain of LysTP712 to the fluorescent mCherry protein. Binding of this reporter protein took place at the septa of both wildtype and L. lactis ΔftsH cells as shown by fluorescence microscopy. Nonetheless, fluorescence spectroscopy demonstrated that mutant cells bound 40% less protein. In conclusion, the non-lytic phenotype of L. lactis ΔftsH is not due to direct action of the FtsH protease on the phage lytic proteins but rather to a putative function of FtsH in modulating the architecture of the L. lactis cell envelope that results in a lower affinity of the phage endolysin to its substrate.This work has been supported by grant BIO2013-46266R (MINECO, Spain). BM, PG, and AR also acknowledge funding by GRUPIN14-139 Plan de Ciencia, Tecnología e Innovación 2013-2017 (Principado de Asturias, Spain) and FEDER EU funds.Peer reviewe

Study of the synergistic impact of Fe3O4, Na2CO3 and organic C on kaolin-based lightweight aggregates by a DOE (Mixture Experiments) approach

The compositional synergies involved in the thermal formation of lightweight aggregates (LWAs) have been investigated through four pure phases: non-expansive kaolin (K); cork powder (C); sodium carbonate (N) and magnetite-Fe3O4 (M). Mixture Experiments has been applied for formulation, modeling and optimization. LWAs have been manufactured from 36 starting mixtures and the main technological properties have been characterized: bloating index (BI), particle density (ρrd), water absorption (WA24) and crushing strength (S). Maximum BI and WA24 together with minimum density are associated with the addition of a significant amount of iron phase in combination with small proportions of organic carbon (Optimal [BI > 60%]: 56.0% K + 40.2% M + 3.9% C + 0% N), while S increases antagonistically with expansion. Iron reduction by incomplete combustion of C appears to be critical in pore formation and concomitant bloating. N has enhanced the sphericity of the expanded specimens. The contrast between experimental and estimated data has shown that the models have generally performed very well.This research was conducted as a part of the ECO-MET-AL Project, PID2019-109520RB-I00 / AEI / 10.13039/501100011033, “Can industrial and mining metalliferous wastes produce green lightweight aggregates? Applying the Circular Economy” funded by the Spanish Ministry of Science, Innovation and Universities and ERDF funds, framed in the “Ayudas a Proyectos I + D + i en el marco de los Programas Estatales de Generación de Conocimiento y Fortalecimiento Científico y Tecnológico del Sistema de I + D + i y de I + D + i orientada a los Retos de la Sociedad, Convocatoria 2019”

Can statistical methods optimize complex multicomponent mixtures for sintering ceramic granular materials? A case of success with synthetic aggregates

The relationship between the proportions of multicomponent mixtures with the technological properties of ceramic granular materials (synthetic aggregates) has been studied using statistical methods. The four phases involved in the formulations have been: kaolin (K) as aluminosilicate source; cork powder (C) as organic carbon source; sodium carbonate (N) as flux and pyrite (P) as source of iron and sulfur. The Mixture Experiments - Design of Experiments (ME-DOE) has been the statistical methodology applied from the initial configuration of the 36 starting formulations to the final validation of the models and optimums. After granulation, artificial aggregates have been obtained by sintering in a rotary kiln, and their main technological properties have been determined. Bloating index (BI), particle density (ρrd), water absorption (WA24) and crushing strength (S) were selected as the four key characteristics to be modeled and optimized, using response surface and effect plots to assess the effect of K, C, N and P on such properties. 32 out of 36 starting varieties met the density criteria for lightweight aggregates. In the optimum formulations obtained, the minimum percentage of K was 83 wt%, so that the variations in the percentages of P, C and N were the critical variables for determining the final properties of the aggregate. The contrast between experimental and estimated data has shown that the models fit adequately, indicating that this type of approach may have enormous potential for future research on artificial aggregates and other ceramic materialsThis research was conducted as a part of the ECO-MET-AL Project, PID2019-109520RB-I00 / AEI / 10.13039/501100011033, “Can industrial and mining metalliferous wastes produce green lightweight aggregates? Applying the Circular Economy” funded by the Spanish Ministry of Science, Innovation and Universities and ERDF funds, framed in the “Ayudas a “Proyectos I + D + i" en el marco de los Programas Estatales de Generación de Conocimiento y Fortalecimiento Científico y Tecnológico del Sistema de I + D + i y de I + D + i orientada a los Retos de la Sociedad, Convocatoria 2019”. Thanks also to the SCAI of the University of Jaén, the University of Castilla-La Mancha and the University of Málaga for their service

Etiopathology of chronic tubular, glomerular and renovascular nephropathies: Clinical implications

Chronic kidney disease (CKD) comprises a group of pathologies in which the renal excretory function is chronically compromised. Most, but not all, forms of CKD are progressive and irreversible, pathological syndromes that start silently (i.e. no functional alterations are evident), continue through renal dysfunction and ends up in renal failure. At this point, kidney transplant or dialysis (renal replacement therapy, RRT) becomes necessary to prevent death derived from the inability of the kidneys to cleanse the blood and achieve hydroelectrolytic balance. Worldwide, nearly 1.5 million people need RRT, and the incidence of CKD has increased significantly over the last decades. Diabetes and hypertension are among the leading causes of end stage renal disease, although autoimmunity, renal atherosclerosis, certain infections, drugs and toxins, obstruction of the urinary tract, genetic alterations, and other insults may initiate the disease by damaging the glomerular, tubular, vascular or interstitial compartments of the kidneys. In all cases, CKD eventually compromises all these structures and gives rise to a similar phenotype regardless of etiology. This review describes with an integrative approach the pathophysiological process of tubulointerstitial, glomerular and renovascular diseases, and makes emphasis on the key cellular and molecular events involved. It further analyses the key mechanisms leading to a merging phenotype and pathophysiological scenario as etiologically distinct diseases progress. Finally clinical implications and future experimental and therapeutic perspectives are discussed

Seasonal and Sexual Differences in the Microbiota of the Hoopoe Uropygial Secretion

The uropygial gland of hoopoe nestlings and nesting females hosts bacterial symbionts that cause changes in the characteristics of its secretion, including an increase of its antimicrobial activity. These changes occur only in nesting individuals during the breeding season, possibly associated with the high infection risk experienced during the stay in the hole-nests. However, the knowledge on hoopoes uropygial gland microbial community dynamics is quite limited and based so far on culture-dependent and molecular fingerprinting studies. In this work, we sampled wild and captive hoopoes of different sex, age, and reproductive status, and studied their microbiota using quantitative polymerase chain reaction (qPCR), fluorescence in situ hybridization (FISH) and pyrosequencing. Surprisingly, we found a complex bacterial community in all individuals (including non-nesting ones) during the breeding season. Nevertheless, dark secretions from nesting hoopoes harbored significantly higher bacterial density than white secretions from breeding males and both sexes in winter. We hypothesize that bacterial proliferation may be host-regulated in phases of high infection risk (i.e., nesting). We also highlight the importance of specific antimicrobial-producing bacteria present only in dark secretions that may be key in this defensive symbiosis. Finally, we discuss the possible role of environmental conditions in shaping the uropygial microbiota, based on differences found between wild and captive hoopoes.This work was supported by the Spanish Ministry of Economy and Competitiveness and European (FEDER) funds (CGL2013-48193-C3-1-P/BOS, CGL2013-48193-C3-2-P/BOS, CGL2017-83103-P), and the Junta de Andalucía (RNM 339, RNM 340). S. M. Rodríguez-Ruano received a grant from the Spanish Ministry of Science and Innovation (FPI program)

Androgen receptor gene and sociosexuality. Does fighting ability moderate the effect of genetics in reproductive strategies?

Springer Nature remains neutral with regard to juris dictional claims in published maps and institutional affiliations.Sociosexuality is a reliable proxy to evaluate the trade-off between short-term and long-term human mating strategies. The androgen receptor (AR) gene CAG-repeats polymorphism regulates the effect of testosterone and the expression of testosterone-related traits commonly associated with short-term mating strategies. According to the strategic pluralism hypothesis, a more effective receptor would prompt a short-term mating strategy to maximize the number of sexual partners, but studies are inconclusive and contradictory. The effect of a particular gene in behavior is frequently small and affected by the social environment and other variables, particularly psychological and personality traits. In the current study we propose the effect of the AR gene polymorphism in sociosexuality to be moderated by self-perceived fighting ability, a psychological attribute relevant in intrasexual competition. Our objective is to reveal if the CAG polymorphism is associated with a short-term strategy as expected from the strategic pluralism hypothesis, or conversely with long-term investments to maximize parental care. We fail to find any effect of the CAG polymorphism over mating strategies. However, self-perceived fighting ability is related to short-term mating orientation but not to the number of past sexual partners. In conclusion, we find no clear evidence about the potential role of CAG polymorphism of the AR gene over sociosexual attitudes and behavior. However, results from other studies suggest that there is evidence that genetic factors influence sociosexuality, but it is necessary to consider simultaneously more than a single genetic polymorphism and other psychological and physiological variablesThis study was supported by a postdoctoral proj ect from Universidad del Desarrollo for author Nohelia T. Valenzuela and funded by the project BIOUAM03-2019 of the Departmento de Biología of the Universidad Autónoma de Madri

Effect of RecA inactivation on quinolone susceptibility and the evolution of resistance in clinical isolates of Escherichia coli

This study was presented in part at the Twenty-Ninth European Congress of Clinical Microbiology and Infectious Diseases, Amsterdam, The Netherlands, 2019 (Poster Presentation P1339).[Background] SOS response suppression (by RecA inactivation) has been postulated as a therapeutic strategy for potentiating antimicrobials against Enterobacterales.[Objectives] To evaluate the impact of RecA inactivation on the reversion and evolution of quinolone resistance using a collection of Escherichia coli clinical isolates.[Methods] Twenty-three E. coli clinical isolates, including isolates belonging to the high-risk clone ST131, were included. SOS response was suppressed by recA inactivation. Susceptibility to fluoroquinolones was determined by broth microdilution, growth curves and killing curves. Evolution of quinolone resistance was evaluated by mutant frequency and mutant prevention concentration (MPC).[Results] RecA inactivation resulted in 2–16-fold reductions in fluoroquinolone MICs and modified EUCAST clinical category for several isolates, including ST131 clone isolates. Growth curves and time–kill curves showed a clear disadvantage (up to 10 log10 cfu/mL after 24 h) for survival in strains with an inactivated SOS system. For recA-deficient mutants, MPC values decreased 4–8-fold, with values below the maximum serum concentration of ciprofloxacin. RecA inactivation led to a decrease in mutant frequency (≥103-fold) compared with isolates with unmodified SOS responses at ciprofloxacin concentrations of 4×MIC and 1 mg/L. These effects were also observed in ST131 clone isolates.[Conclusions] While RecA inactivation does not reverse existing resistance, it is a promising strategy for increasing the effectiveness of fluoroquinolones against susceptible clinical isolates, including high-risk clone isolates.This study was funded by the Instituto de Salud Carlos III, Ministerio de Economía y Competitividad—co-financed by European Development Regional Fund ‘A way to achieve Europe’ ERDF, Spanish Network for Research in Infectious Diseases (REIPI RD12/0015 and RD16/0016). Supported by Plan Nacional de I+D+i 2013‐2016 and Instituto de Salud Carlos III, Subdirección General de Redes y Centros de InvestigaciónCooperativa, Ministerio de Economía, Industria y Competitividad, Spanish Network for Research in Infectious Diseases (PI14/00940, PI17/01501, AC16/00072, RD16/0016/0001 and REIPI RD16/0016/0009) ‐ co-financed by European Development Regional Fund ‘A way to achieve Europe’, Operative Programme Intelligent Growth 2014‐2020.Peer reviewe