Tag: C. elegans

Anna Laromaine and Zhongrui Luo participate in the VI Spanish Worm Meeting in Valencia

Written by Anna May on March 8, 2017. Posted in Conferences, News.

Anna and Luo will attend on 9th-10th March the VI Spanish Worm Meeting in Valencia (Spain).

Anna will give the talk on “Evaluation of albumin pre-coated SPIONS in cell culture and C. elegans“ on Friday, 10th March, at 9 am.

Luo will present the poster on “Evaluation of the nano-bio interactions between Au-NPs and Caenorhabditis elegans“ (Laura González-Moragas, Zhongrui Luo, Anna Roig, Anna Laromaine).

The Spanish Worm Meeting (SWM) is a biennial gathering of the scientific communitiy working with C. elegans. It covers a wide range of topics, including development, neurobiology, aging and disease, metabolism and new technologies applied to C. elegans.

In the website www.gusano.info you can find information about previous Spanish Worm Meetings and resources related to C. elegans (research groups, wormbase, wormbook, etc.).

We hope they enjoy the meeting!

Accepted paper in Acta Biomaterialia on testing gold nanoparticles in vivo using C. elegans

Written by Anna May on February 8, 2017. Posted in New publications, News.

The paper “In vivo testing of gold nanoparticles using the Caenorhabditis elegans model organism” has been publised in Acta Biomaterialia (Available online 1 February 2017; doi: 10.1016/j.actbio.2017.01.080).

The authors of the paper are Laura González-Moragas, Pascal Berto, Clara Vilches, Romain Quidant, Androniki Kolovou, Rachel Santarella-Mellwig, Yannick Schwab, Stephen Stürzenbaum, Anna Roig, and Anna Laromaine.

The paper is a result of a collaboration between the NN Group at ICMAB (González-Moragas, Roig and Laromaine), the ICFO-Institut de Ciències Fotòniques (Berto, Vilches and Quidant), the European Molecular Biology Laboratory, EMBL in Heidelberg, Germany (Kolovou, Santarella-Mellwig, Schwab) and King’s College London in UK (Stürzenbaum).

Congratulations!

Abstract:

Gold nanoparticles (AuNPs) are present in many man-made products and cosmetics, and are also used by the food and medical industries. Tight regulations regarding the use of mammalian animals for product testing can hamper the study of the specific interactions between engineered nanoparticles and biological systems. Invertebrate models, such as the nematode Caenorhabditis elegans (C. elegans), can offer alternative approaches during the early phases of nanoparticle discovery.

Panels B and C are optical microscopy images of B) 11-nm and C) 150-nm AuNPs treated worms. 11-nm AuNPs appear pink, and 150-nm AuNPs appear blue.

Here, we thoroughly evaluated the biodistribution of 11-nm and 150-nm citrate-capped AuNPs in the model organism C. elegans at multiple scales, moving from micrometric to nanometric resolution and from the organism to cellular level. We confirmed that the nanoparticles were not able to cross the intestinal and dermal barriers. We investigated the effect of AuNPs on the survival and reproductive performance of C. elegans, and correlated these effects with the uptake of AuNPs in terms of their number, surface area, and metal mass. In general, exposure to 11-nm AuNPs resulted in a higher toxicity than the larger 150-nm AuNPs. NP aggregation inside C. elegans was determined using absorbance microspectroscopy, which allowed the plasmonic properties of AuNPs to be correlated with their confinement inside the intestinal lumen, where anatomical traits, acidic pH and the presence of biomolecules play an essential role on NP aggregation. Finally, quantitative PCR of selected molecular markers indicated that exposure to AuNPs did not significantly affect endocytosis and intestinal barrier integrity.

Prof. Stephen Sturzenbaum will give an ICMAB Lecture on toxicity of metals on biological systems

Written by Anna May on January 20, 2017. Posted in Conferences, News.

It is a pleasure for us to invite you to the ICMAB Lecture entitled: “Juggling essential and toxic metals – a worm’s eye view of a Toxicogenomic challenge”

By Prof. Stephen Sturzenbaum from the group of Toxicogenomics from King’s College London (UK).

Date: Friday, January 20th
Time: 12.00 pm
Place: ICMAB – Sala d’actes Carles Miravitlles

Abstract: Some metals are exclusively toxic to biological systems and classified as being non-essential, others are essential for life. Nevertheless, above certain threshold concentrations all (including the essential ones) become toxic. Homeostasis of essential elements and detoxification of non-essential elements are thus vital drivers of well-being, longevity and survival. By exploiting genomic, transcriptomic and toxicological tools within the model nematode C. elegans we identified and characterized intricate pathways that not only form the foundations of metallomics but facilitate further explorations within the field of nanomaterials.

Short bio: Professor Stephen Sturzenbaum holds a personal chair in Toxicogenomics at King’s College London and was recently awarded a Senior Doctorate (DSc) from Cardiff University for his work on “Toxicogenomics on Terrestrial Worms”. Stephen pioneered the use of molecular genetic tools in the common earthworm, and in doing so was instrumental in establishing the earthworm as a sentinel soil macroinvertebrate model organism of environmental importance. Stephen’s second stream of work has focussed on promoting the use of the more established C. elegans model organism to address the burgeoning themes of metallobiology, toxicogenomics and nanoparticle toxicology. Laura González, from our group, who did her thesis on evaluating nanoparticles’ toxicity on C. elegans, did an internship at his laboratory during Feb-May 2016.

If you would like to arrange a meeting with Prof. Stephen Stürzenbaum please contact: Dr. Anna Laromaine (alaromaine@icmab.es)

Excellent cum laude for Laura González thesis on “Evaluating inorganic nanoparticles in the living organism C. elegans”!

Written by Anna May on December 16, 2016. Posted in Awards and scholarships, News, Projects News.

The NN group members would like to congratulate Laura González for her excellent work on the Ph.D. thesis defense!

Laura’s thesis is entitled “Evaluating inorganic nanoparticles in the living organism Caenorhabditis elegans” and has been supervised by Dr. Anna Laromaine and Dr. Anna Roig, from the NN group.

The jury was formed by Dr. Maria Vallet-Regí (Universidad Complutense de Madrid, Spain), Dr. Stefaan Soenen (KU Leuven, Belgium) and Dr. Joel N. Meyer (Duke University, USA).

Congratulations Laura!

Today Joel N. Meyer from Duke University gives a Seminar at ICMAB on “Mechanisms of uptake and toxicity of Ag NP in C. elegans”

Written by Anna May on December 15, 2016. Posted in Conferences, News.

Prof. Joel N. Meyer will give a Seminar entitled “Mechanisms of uptake and toxicity of silver nanoparticles in Caenorhabditis elegans“, today, December 15, at 12 pm at ICMAB Conference Room Carles Miravitlles.

Prof. Joel N. Meyer is Associate Professor and Director of Graduate Studies at Nicholas School of the Environment and Center for the Environmental Implications of Nanotechnology (CEINT), at Duke University, NC, USA.

Short abstract:

Engineered nanomaterials offer great opportunities due to their novel properties. However, there is concern that these novel properties may also result in deleterious effects on human and ecological health that are difficult to predict based only on an understanding of the chemical makeup. We tested a number of nanoparticles (NPs) for toxicity in the nematode model Caenorhabditis elegans, and found that certain silver NPs (AgNPs) were the most toxic of the NPs that we had tested. We therefore extended our studies to characterize environmental factors that might alter AgNP toxicity, as well as the uptake and mechanism of toxicity of AgNPs in C. elegans.

Because much AgNP waste is expected to end up in aquatic ecosystems, we tested the influence of environmental variables on toxicity. We found that higher ionic strength, the presence of natural organic matter, and sulfidation of the AgNPs (expected to occur in many environments after AgNP release) all significantly reduced Ag NP toxicity. Using physicochemical, genetic, and pharmacological rescue approaches, we found that the most toxic AgNPs -generally, the smallest- caused their effects largely via dissolution. Some AgNPs (typically less soluble due to size or coating) also caused toxicity via generation of reactive oxygen species, an effect specific to nanoparticulate silver. This effect was masked by the toxicity of silver ions except when dissolution was very limited. The toxicity of the tested AgNPs was almost never greater than would result from complete dissolution of the same mass of silver. We also found that endocytosis was an important mechanism for AgNP uptake. However, the specific mechanisms by which AgNPs or released silver ion cause toxicity remain unclear. Because AgNPs are used to kill microbes, and mitochondria are endosymbiotic descendants of bacteria, current studies are focused on testing the possibility that AgNPs cause some of their toxicity via disruption of mitochondrial function.

If you would like to arrange a meeting with Prof. Joel N. Meyer please contact: Dr. Anna Laromaine (alaromaine@icmab.es).

Laura González will defend her Doctoral Thesis on Friday, December 16th at 12 pm at ICMAB

Written by Anna May on December 14, 2016. Posted in General News, News, Projects News.

This Friday 16th of December Laura González is going to defend her Doctoral Thesis entitled “Evaluating inorganic nanoparticles in the living organism Caenorhabditis elegans”, supervised by Dr. Anna Laromaine and Dr. Anna Roig.

Abstract:
In this thesis, we have used the simple model organism Caenorhabditis elegans as an in vivo biological system to screen inorganic nanoparticles (NPs) with biomedical uses. In particular, we have assessed the behaviour of two types of particles with different composition, size and surface properties: iron oxide NPs coated with citrate and bovine serum albumin, and gold nanoparticles of two different sizes. We have studied their interactions with C. elegans including their uptake, fate, biological effects and NP-responsive molecular mechanisms, and compared our results with previous studies. To this end, we have combined toxicity tests, materials science and imaging techniques and gene expression analysis. We have been able to perform this biological evaluation in the synthetic laboratory where the particles were synthesized and characterised due to the advantageous experiments features of C. elegans.In summary, this thesis exploits the potential of C. elegans as a simple animal model to evaluate NPs in the initial stages of development and contributes to: (i) a systematic and comprehensive evaluation of NPs in C. elegans, in particular studying the influence of NP properties (size, surface coating and core composition) on their in vivo effects, (ii) extend the toolkit of techniques available to characterise nano-bio interactions in small organisms.

The Jury Members will be:

President: Dr. Maria Vallet-Regí (Universidad Complutense de Madrid, Spain)
Secretary: Dr. Stefaan Soenen (KU Leuven, Belgium)
Vocal: Dr. Joel N. Meyer (Duke University, USA)

Everyone is invited to join the presentation, that will be held at 12 pm at ICMAB Conference Room Carles Miravitlles. After the defense, there will be a “pica-pica” for everyone in the dining room.

Anna Roig attends the B·Debate on Imaging for Life: from Molecules to Diagnostics and Therapy at CosmoCaixa

Written by Anna May on November 8, 2016. Posted in Conferences, News.

Anna Roig will attend the B·Debate on Imaging for Life. From Molecules to Diagnostics and Therapy, that takes place on November 8-9 at CosmoCaixa (Barcelona).

The scientific leaders of this B·Debate are Francesc Xavier Avilés, from the Institut de Biotecnologia i Biomedicina (IBB) – Universitat Autònoma de Barcelona (UAB) and Boris Turk, from “Jožef Stefan” Institute (IJS) – Ljubljana University, Slovenia.

The objective is to bring together national and international experts in the field to discuss the future perspectives and strategies for the current challenges on molecular imaging.

The B·Debate will focus on molecular, cell, tissue and small animals research, and to their biomedical applications, including non-invasive diagnostic, imaging-guided surgery, multimodal scanning and theranostics.

For sure this B·Debate will be useful for Anna and for the group, since imaging is a powerful tool to study the interaction of inorganic nanoparticles with living organisms, such as C. elegans, which is the topic of Laura González thesis, for example.

This B·Debate is an iniciative of Biocat and l’Obra Social “la Caixa”, together with the Institut de Biotecnologia i Biomedicina (IBB) – Universitat Autònoma de Barcelona (UAB) and “Jožef Stefan” Institute (IJS) – Ljubljana University (Slovenia).

More information about the B·Debate:

Anna Roig at the HINT COST Action Final Meeting in Aveiro, Portugal

Written by Anna May on October 9, 2016. Posted in Conferences, News.

The Final Meeting of the COST Action on Hybrid Interfaces (HINT) will take place on October 10-12, 2016, at the Reitoria building of the University of Aveiro, Portugal. The meeting aims at sharing the learned lessons on design, control, and dynamics of interfaces in hybrid organic-inorganic materials over the last four years in which the different partners have worked on this topics.

Anna Roig will participate in the meeting and will give a talk on “Bio-screening of protein coated SPIONs: in vitro and in vivo by the C. elegans model” (Monday, October 10, 5.40 pm).

For more information on the agenda, please visit the conference webiste: http://costhint.web.ua.pt/

Farewell to Iván and Seminar of Esther Dalfo on biomedical applications of C. elegans

Written by Anna May on September 15, 2016. Posted in Conferences, News, Welcome and farewell.

Today during the group meeting we said goodbye to Iván, who is leaving to continue his Ph.D. thesis in Colombia. Iván is a great chemist, who works with magnetic graphene for water decontamination. We wish him a lot of success in his thesis and in his future endeavours!

On the other hand, Esther Dalfo gave us a nice talk on biomedical applications of C. elegans “Investigating neurodegeneration by using the nematode Caenorhabditis elegans”. Esther is an Associate Researcher at the Institute of Neuroscience of the UAB, specialized in neurodegeneration and human genetics. Thank you!

Hot off the press: New article accepted in Acta Biomaterialia!

Written by Anna May on July 20, 2016. Posted in New publications, News.

The article “Bio-identity and fate of albumin-coated SPIONs evaluated in cells and by the C. elegans model” (Si-Ming Yu, Laura González-Moragas, Maria Milla, Androniki Kolovou, Rachel Santarella-Mellwig, Yannick Schwab, Anna Laromaine, Anna Roig) is now published online in Acta Biomaterialia at:
http://www.sciencedirect.com/science/article/pii/S174270611630349X.
doi:10.1016/j.actbio.2016.07.024.

Abstract: Nanoparticles, whose surface adsorbs proteins in an uncontrolled and non-reproducible manner will have limited uses as nanomedicinal products. A promising approach to avoid nanoparticle non-specific interactions with proteins is to design bio-hybrids by purposely pre-forming a protein corona around the inorganic cores. Here, we investigate, in vitro and in vivo, the newly acquired bio-identity of superparamagnetic iron oxide nanoparticles (SPIONs) upon their functionalization with a pre-formed and well-defined bovine serum albumin (BSA) corona. Cellular uptake, intracellular particle distribution and cytotoxicity were studied in two cell lines: adherent and non-adherent cells. BSA decreases nanoparticle internalization in both cell lines and protects the iron core once they have been internalized. The physiological response to the nanoparticles is then in vivo evaluated by oral administration to Caenorhabditis elegans, which was selected as a model of a functional intestinal barrier. Nanoparticle biodistribution, at single particle resolution, is studied by transmission electron microscopy. The analysis reveals that the acidic intestinal environment partially digests uncoated SPIONs but does not affect BSA-coated ones. It also discloses that some particles could enter the nematode’s enterocytes, likely by endocytosis which is a different pathway than the one described for the worm nutrients.

Keywords: Iron oxide nanoparticles; Protein corona; Cytotoxicity; C. elegans; Biodistribution.

Congratulations to all the authors!