The Impact of Fullerenes as Doxorubicin Nano-Transporters on Metallothionein and Superoxide Dismutase Status in MCF-10A Cells.

This study aimed to synthesise C60-DOX complexes followed by the analysis of their effect on the concentration of metallothionein (MT) as a non-enzymatic antioxidant and on the concentration and activity of superoxide dismutase (SOD) as an antioxidant enzyme in healthy human mammary MCF-10A cells. Dynamic light scattering and electrophoretic light scattering were used to establish the size and zeta potential of the complexes. The MT and SOD concentrations were determined using the ELISA method; SOD activity was determined by tetrazolium salt reduction inhibition. Lower MT concentration following exposure of cells to both DOX and C60 fullerene compared to the control sample was found. However, the concentration of this protein increased as a consequence of the C60-DOX complexes action on MCF-10A cells compared to the control. C60 used alone did not affect the concentration and activity of SOD in MCF-10A cells. Application of free DOX did not activate cellular antioxidant defence in the form of an increase in SOD concentration or its activity. In contrast treatment of cells with the C60-DOX complex resulted in a decrease in SOD1 concentration and a significant increase in SOD activity compared to cells treated with free DOX, C60 and control. Thus, it was found that C60-DOX complexes showed potential for protective effects against DOX-induced toxicity to MCF-10A cells.

Registro OBELISCO-SAC. OBsErvaciones de cLinicas, Instituciones y Servicios de Cardio-Oncología SAC / OBELISCO-SAC Registry. OBsErvations from cLinics, InstitutionS and Cardio-Oncology services SAC

RESUMEN Introducción: La cardio-oncología (CO) es una nueva disciplina, que genera nuevas áreas de trabajo en las instituciones. Desconocemos cuántos equipos de CO existen en nuestro país, su estructura y el manejo de los pacientes. Objetivos: Nuestro objetivo primario es reportar cuántos centros de CO existen en nuestro país, y de ellos cuántos trabajan de acuerdo con las recomendaciones de guías y consensos. Secundariamente, definir la especialidad y formación de los médicos integrantes, si se realiza evaluación de riesgo previo al inicio del tratamiento oncológico, cómo se evalúa la función ventricular y cómo se utilizan los biomarcadores. Material y métodos: Registro nacional, multicéntrico, transversal, descriptivo, y prospectivo que incluyó 51 instituciones generales, de oncología y/o de cardiología que referían poseer grupos de trabajo o servicios de CO. Resultados: De los 51 centros, pertenecen al ámbito público el 47,1% y al privado el 52,9%. El 49% se halla en la Ciudad Autónoma de Buenos Aires, el 17,6% en la Provincia de Buenos Aires y el resto en otros lugares del país. Sobre 47 centros, el 48,9% considera funcionar de acuerdo con las recomendaciones de Guías Internacionales y el Consenso de la Sociedad Argentina de Cardiología. El 27,7% de los centros realiza siempre estratificación de riesgo cardio-oncológico o cardiovascular antes de iniciar el tratamiento. Un 35,3% de los centros deriva siempre a cardiología a los pacientes que iniciarán un tratamiento potencialmente cardiotóxico, un 47,1% ocasionalmente. El 43,1% de los centros realiza ecocardiografía basal en todos los pacientes, el 56,9% solo en algunos. Durante el seguimiento el ecocardiograma se indica de acuerdo con el esquema utilizado en el 64,7% y en el resto según su evolución. Todos los centros evalúan la fracción de eyección ventricular izquierda mediante ecocardiografía, en el 68,1% bidimensional. El 63,8% utiliza el análisis de la deformación longitudinal sistólica global. El 47,1% deriva algunos pacientes a resonancia cardíaca y el 35,3% a tomografía cardíaca. Solo el 7,8% utiliza biomarcadores. El 5,9% indica siempre prevención primaria con antagonistas neurohormonales. El dexrazoxano es utilizado en el 5,9%, la antraciclina liposomal en el 74,5%. Frente a la aparición de cardiotoxicidad, el 76,5% inicia tratamiento cardioprotector. El 41% suspende la quimioterapia, el 47% la modifica. Conclusiones: este es el primer registro nacional de CO. Brinda información y un panorama actual del estado de esta subespecialidad en nuestro país. Casi la mitad de los centros consideró funcionar de acuerdo con Guías y Consensos. Solo un tercio de los pacientes que van a iniciar tratamiento oncológico potencialmente cardiotóxico son derivados a CO. El método más utilizado en nuestro país para evaluar la función ventricular es el ecocardiograma bidimensional, los biomarcadores son poco utilizados.

ABSTRACT Background: Cardio-oncology (CO) is a new discipline that generates new work areas within the institutions. We ignore how many CO teams exist in our country, their structure and how patients are managed. Objectives: Our primary objective is to report how many CO centers exist in our country, and how many of them work according to the recommendations of guidelines and consensus statements. We also want to define the specialty and specific training of the physicians involved, determine if they perform risk assessment before cancer treatment, establish the method used to assess ventricular function and how biomarkers are used. Methods: The OBELISCO registry is a national, multicenter, cross-sectional, descriptive and prospective registry including 51 general hospitals, cancer centers and institutions specialized in cardiology with CO work groups or services. Results: Of the 51 centers, 47.1% were public hospitals and 52.9% were private centers. Most centers were in the Autonomous City of Buenos Aires (49%) and in the Province of Buenos Aires and the rest were distributed throughout the country. Of 47 centers, 48.9% considered that their institution had CO services complying with the recommendations of international guidelines and of the consensus statement of the Argentine Society of Cardiology. Global cardio-oncological or cardiovascular risk assessment is always performed in 27.7% of the centers before starting treatment. Patients who will start potentially cardiotoxic treatment are always referred to cardiology in 35.3% of the centers and are sometimes referred to cardiology in 47.1%. Baseline echocardiography is performed in all the patients before starting treatment in 43.1% of the centers and only in some patients in 56.9%. During follow-up, echocardiography is indicated according to the treatment schedule used in 64.7% and according to the patients' outcome in the rest of the centers. All the centers evaluate left ventricular ejection fraction with echocardiography, and 68.1% use twodimensional echocardiography. Global longitudinal systolic strain is used in 63.8% of the centers. Only 47.1% order cardiac magnetic resonance imaging in some patients, and 35.3% indicate cardiac computed tomography scan. Biomarkers are used in only 7.8% of the centers. Primary prevention with neurohormonal antagonist drugs is always indicated in 5.9% of the centers. Dexrazoxane is used in only 5.9% and liposomal anthracycline in 74.5% If cardiotoxicity develops, 76.5% indicate cardioprotection, 41% discontinue chemotheraphy and 47% modify cancer treatment. Conclusions: This is the first national CO registry. It provides information and a current outlook of the status of this subspecialty in our country. Almost 50% of the centers considered to be functioning in line with guidelines and consensus statements. Only one third of the patients who will initiate cancer treatment with potentially cardiotoxic drugs are referred to CO. Two-dimensional echocardiography is the method most used in our country to evaluate ventricular function; biomarkers are scarcely used.

Activity of CdTe Quantum-Dot-Tagged Superoxide Dismutase and Its Analysis in Capillary Electrophoresis.

Quantum dots (QDs) have a broad range of applications in cell biolabeling, cancer treatment, metastasis imaging, and therapeutic drug monitoring. Despite their wide use, relatively little is known about their influence on other molecules. Interactions between QDs and proteins can influence the properties of both nanoparticles and proteins. The effect of mercaptosuccinic acid-capped CdTe QDs on intercellular copper-zinc superoxide dismutase (SOD1)-one of the main enzymatic antioxidants-was investigated. Incubation of SOD1 with QDs caused an increase in SOD1 activity, unlike in the case of CdCl2, which inhibited SOD1. Moreover, this effect on SOD1 increased with the size and potential of QDs, although the effect became clearly visible in higher concentrations of QDs. The intensity of QD-SOD1 fluorescence, analyzed with the use of capillary electrophoresis with laser-induced fluorescence detection, was dependent on SOD1 concentration. In the case of green QDs, the fluorescence signal decreased with increasing SOD1 concentration. In contrast, the signal strength for Y-QD complexes was not dependent on SOD1 dilutions. The migration time of QDs and their complexes with SOD1 varied depending on the type of QD used. The migration time of G-QD complexes with SOD1 differed slightly. However, in the case of Y-QD complexes with SOD1, the differences in the migration time were not dependent on SOD concentration. This research shows that QDs interact with SOD1 and the influence of QDs on SOD activity is size-dependent. With this knowledge, one might be able to control the activation/inhibition of specific enzymes, such as SOD1.

The Application of Nanoparticles in Diagnosis and Treatment of Kidney Diseases.

Nanomedicine is currently showing great promise for new methods of diagnosing and treating many diseases, particularly in kidney disease and transplantation. The unique properties of nanoparticles arise from the diversity of size effects, used to design targeted nanoparticles for specific cells or tissues, taking renal clearance and tubular secretion mechanisms into account. The design of surface particles on nanoparticles offers a wide range of possibilities, among which antibodies play an important role. Nanoparticles find applications in encapsulated drug delivery systems containing immunosuppressants and other drugs, in imaging, gene therapies and many other branches of medicine. They have the potential to revolutionize kidney transplantation by reducing and preventing ischemia-reperfusion injury, more efficiently delivering drugs to the graft site while avoiding systemic effects, accurately localizing and visualising the diseased site and enabling continuous monitoring of graft function. So far, there are known nanoparticles with no toxic effects on human tissue, although further studies are still needed to confirm their safety.

The Function of Transthyretin Complexes with Metallothionein in Alzheimer's Disease.

Alzheimer's disease (AD) is one of the most frequently diagnosed types of dementia in the elderly. An important pathological feature in AD is the aggregation and deposition of the ß-amyloid (Aß) in extracellular plaques. Transthyretin (TTR) can cleave Aß, resulting in the formation of short peptides with less activity of amyloid plaques formation, as well as being able to degrade Aß peptides that have already been aggregated. In the presence of TTR, Aß aggregation decreases and toxicity of Aß is abolished. This may prevent amyloidosis but the malfunction of this process leads to the development of AD. In the context of Aßplaque formation in AD, we discuss metallothionein (MT) interaction with TTR, the effects of which depend on the type of MT isoform. In the brains of patients with AD, the loss of MT-3 occurs. On the contrary, MT-1/2 level has been consistently reported to be increased. Through interaction with TTR, MT-2 reduces the ability of TTR to bind to Aß, while MT-3 causes the opposite effect. It increases TTR-Aß binding, providing inhibition of Aß aggregation. The protective effect, assigned to MT-3 against the deposition of Aß, relies also on this mechanism. Additionally, both Zn7MT-2 and Zn7MT-3, decrease Aß neurotoxicity in cultured cortical neurons probably because of a metal swap between Zn7MT and Cu(II)Aß. Understanding the molecular mechanism of metals transfer between MT and other proteins as well as cognition of the significance of TTR interaction with different MT isoforms can help in AD treatment and prevention.