Successful Latin American initiatives in biophysics

The II LAFeBS Congress aimed to promote a closer interaction between Latin American and Iberian Peninsula scientists in their respective fields of research, from structural proteomics to molecular bioenergetics. The speakers at this event reflected the importance and development of Biophysics in Latin American Countries, including Portugal and Spain; with 13 of them being invited to write review articles for this special issue of Biophysical Reviews. We hope that the integration of biophysics and biophysicists in Latin America, together with Portugal and Spain, through LAFeBS and POSLATAM can contribute to the future development of biophysics in these two historical partner regions.Instituto Multidisciplinario de Biología Celula

Liposomes as Matrices to Hold Bioactive Compounds for Drinkable Foods: Their Ability to Improve Health and Future Prospects

The aim of this chapter is to describe the use of bioactive compounds with beneficial effects on human health beyond their basic nutritional value. Bioactive compounds like vitamin E, vitamin C, and fatty acids (omega-3 and omega-6) have an important nutritional contribution and are related to the prevention of certain diseases with global impact such as cancer. However, the addition of vitamins in a food product is not easy: E is destroyed by UV-light, and C is dramatically reduced during heat processes. The use of liposomes as matrices to hold bioactive compounds appears to be a promising solution. Liposomes were made of natural soybean lecithin, which has a great nutritional importance, and more so combined with stearic acid or calcium stearate (CaS). Thus, this stabilize liposomes and contribute to the stability of bioactive compounds and to preserve their activity. The stability of bioactive compounds/liposomes incorporated into aqueous food must be demonstrated in properties such as oxidative tendency, morphology, size, and membrane packaging after heat treatment processes. But to make a product applicable at the commercial level, its texture and mouthfeel arising from the ingestion of drinkable foods are all-important to consumer’s choice and sensory acceptability must not undergo any modification

Why Produce Food-Bioactive Compounds to Generate Functional Grade Foods?

Functional foods are those with health benefits but cannot incorporate and protect from oxidation or deterioration, maintaining the bioactive compounds (BC) activity. The liposomes have several advantages for BC encapsulation: ease of obtention, characterization, scaling-up, lipid protection for hydrophilic and lipophilic BC, and best, they are made with natural lipids of alimentary grade. In our studies, liposomes were made of soy phosphatidylcholine (SPC) with Stearic Acid or Calcium Stearate as membrane stabilizer. They encapsulated BC as vitamin E, vitamin C and folic acid (B9). The liposome’s design strategy is that SPC lipid’s components are BC like choline and essential fatty acids. These liposomes preserved and maintain the activity of the thermolabile vitamins C and B9. Like milk and fruit juice, in various food types can incorporate liposomes protecting BC. A series of laboratory studies will be performed to select the most stable liposomal formulations, like characterization, encapsulation efficiency, physicochemical, microbiological, thermal and sensory stability. Liposomes- BC design and development are discussed in the chapter. The food heat treatment and the conditions/storage time are also crucial and must be considered in these studies. Finally, incorporating the BC into a food production line is feasible with an excellent economic prospect until supermarket shelves are reached, like our food product proposal

G4.5 Pamam Dendrimer-Risperidone: Biodistribution and Behavioral Changes in In Vivo Model

Dendritic polymers are considered as emerging and outstanding carriers as modern medicinal systems due to their derivatisable branched architecture and possibility to modify them in numerous ways. Here, G4.5 PAMAM dendrimers were obtained as carriers of the antipsychotic drug risperidone. Despite their extensive applicability in the pharmaceutical field, the use of dendrimers as carriers in biological systems is constrained due to their inherent associated toxicity. The biocompatibility of dendrimers and dendrimer-risperidone complexes was evaluated in vivo for biological performance. To this end, the pharmacokinetics and biodistribution after oral treatment of free risperidone and dendrimer-risperidone complexes were studied in healthy mice. Also, the behavioral changes such as locomotion, aggression, dominance in male and female mice were evaluated both after a single dose and after daily therapy for 8 days. Also, in vivo effects of risperidone and dendrimer-risperidone complexes on the locomotion of zebrafish larvae were explored. The data obtained suggest that the unmetabolized risperidone complexes increase the arrival to the brain after 90 minutes. On the other hand, behavioral studies showed an increase in the potency of the drug in animals treated with the complexesFil: Prieto, Maria Jimena. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: del Rio Zabala, Nahuel Eduardo. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Marotta, Cristian Hernán. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Bichara, Darío Román. Fundación Instituto Leloir; ArgentinaFil: Simonetta, Sergio Hernan. Fundación Instituto Leloir; ArgentinaFil: Chiaramoni, Nadia Silvia. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Alonso, Silvia del Valle. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentin

A model based in the radius of vesicles to predict the number of unilamellar liposomes

In particulate systems such as liposomes, concentration units are not enough to describe the drug distribution, as suspensions are not homogeneous. In certain in vitro assays, exposure to different number of particles introduces an extra variable regarding to contact phenomena. the aim is to achieve a rapid estimation of the number of unilamellar liposomes in a suspension. A simple mathematical method was developed; variables were the area and molecular weight of lipids, and the mean size of the liposomes. Unilamellar liposomes were prepared. Size was determined by dynamic light scattering, and then the number of particles were determined by tunable resistive pulse sensing. there was about a 90% coincidence between the theoretical results and the number of counted liposomes. This model could be useful for interpretation of in vitro experiments, when results could depend on the distribution of actives into different quantities of liposomes.Fil: Martinetti Montanari, Jorge Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB | Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB | Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB; ArgentinaFil: Bucci, Paula Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB | Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB | Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB; ArgentinaFil: Alonso, Silvia del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB | Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB | Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular. Grupo Vinculado al IMBICE - Grupo de Biología Estructural y Biotecnología - Universidad Nacional de Quilmes - GBEyB; Argentin

Successful Latin American initiatives in biophysics

The II LAFeBS Congress aimed to promote a closer interaction between Latin American and Iberian Peninsula scientists in their respective fields of research, from structural proteomics to molecular bioenergetics. The speakers at this event reflected the importance and development of Biophysics in Latin American Countries, including Portugal and Spain; with 13 of them being invited to write review articles for this special issue of Biophysical Reviews. We hope that the integration of biophysics and biophysicists in Latin America, together with Portugal and Spain, through LAFeBS and POSLATAM can contribute to the future development of biophysics in these two historical partner regions.Instituto Multidisciplinario de Biología Celula

Effect of Risperidone and Fluoxetine on the Movement and Neurochemical Changes of Zebrafish

Brain developmental disorders in humans, including Autism Spectrum Disorders (ASD) and Down’s syndrome, have been linked to increased serotonin levels. This work was designed to study changes in serotonin levels in the early stages of development with two classes of antipsychotic drugs: Risperidone, a drug that blocks serotonin and dopamine receptors, and fluoxetine, a serotonin reuptake inhibitor. The use of antipsychotic drugs is a solid choice to study the decrease and increase of these neurotransmitters and their influence on development. The study of these parameters will give an idea of the effects of serotonin in early developmental stages. To this end, we examined the effects of risperidone and fluoxetine on the locomotor activity, heart rate and brain development of zebrafish larvae. Our results showed that in larvae exposed to fluoxetine alone, swimming was significantly increased at 9 dpf (days post-fertilization). Erratic and abnormal movements were observed suggesting a toxic effect of fluoxetine. No erratic swimming was observed in larvae treated with fluoxetine plus risperidone. Both drugs presented morphological changes in dopaminergic neurons and mononeurons. Exposure to fluoxetine plus risperidone indicated possible reversal effects. Studies in zebrafish allow obtaining new insights into the side effects of these drugs as well as into the brain control of locomotor activity. Testing several drug-induced changes in behavior and serotonin levels is one of the experimental approaches for screening a new therapeutically relevant compound, and thus, merits further research.Instituto Multidisciplinario de Biología Celula

Effect of Risperidone and Fluoxetine on the Movement and Neurochemical Changes of Zebrafish

Brain developmental disorders in humans, including Autism Spectrum Disorders (ASD) and Down’s syndrome, have been linked to increased serotonin levels. This work was designed to study changes in serotonin levels in the early stages of development with two classes of antipsychotic drugs: Risperidone, a drug that blocks serotonin and dopamine receptors, and fluoxetine, a serotonin reuptake inhibitor. The use of antipsychotic drugs is a solid choice to study the decrease and increase of these neurotransmitters and their influence on development. The study of these parameters will give an idea of the effects of serotonin in early developmental stages. To this end, we examined the effects of risperidone and fluoxetine on the locomotor activity, heart rate and brain development of zebrafish larvae. Our results showed that in larvae exposed to fluoxetine alone, swimming was significantly increased at 9 dpf (days post-fertilization). Erratic and abnormal movements were observed suggesting a toxic effect of fluoxetine. No erratic swimming was observed in larvae treated with fluoxetine plus risperidone. Both drugs presented morphological changes in dopaminergic neurons and mononeurons. Exposure to fluoxetine plus risperidone indicated possible reversal effects. Studies in zebrafish allow obtaining new insights into the side effects of these drugs as well as into the brain control of locomotor activity. Testing several drug-induced changes in behavior and serotonin levels is one of the experimental approaches for screening a new therapeutically relevant compound, and thus, merits further research.Instituto Multidisciplinario de Biología Celula

Diacetylenic lipids in the design of stable lipopolymers able to complex and protect plasmid DNA

Different viral and non-viral vectors have been designed to allow the delivery of nucleic acids in gene therapy. In general, non-viral vectors have been associated with increased safety for in vivo use; however, issues regarding their efficacy, toxicity and stability continue to drive further research. Thus, the aim of this study was to evaluate the potential use of the polymerizable diacetylenic lipid 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DC8,9PC) as a strategy to formulate stable cationic lipopolymers in the delivery and protection of plasmid DNA. Cationic lipopolymers were prepared following two different methodologies by using DC8,9PC, 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), and the cationic lipids (CL) 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP), stearylamine (SA), and myristoylcholine chloride (MCL), in a molar ratio of 1:1:0.2 (DMPC:DC8,9PC:CL). The copolymerization methodology allowed obtaining cationic lipopolymers which were smaller in size than those obtained by the cationic addition methodology although both techniques presented high size stability over a 166-day incubation period at 4C. Cationic lipopolymers containing DOTAP or MCL were more efficient in complexing DNA than those containing SA. Moreover, lipopolymers containing DOTAP were found to form highly stable complexes with DNA, able to resist serum DNAses degradation. Furthermore, neither of the cationic lipopolymers (with or without DNA) induced red blood cell hemolysis, although metabolic activity determined on the L-929 and Vero cell lines was found to be dependent on the cell line, the formulation and the presence of DNA. The high stability and DNA protection capacity as well as the reduced toxicity determined for the cationic lipopolymer containing DOTAP highlight the potential advantage of using lipopolymers when designing novel nonviral carrier systems for use in in vivo gene therapy. Thus, this work represents the first steps toward developing a cationic lipopolymer-based gene delivery system using polymerizable and cationic lipids.Instituto Multidisciplinario de Biología Celula