In recent years there has been an increase in interest in the use of colloidal quantum dots (QDs) in biology and medicine. In particular, QDs can be a perspective nanoscale object for theranostics, in which due to the specific accumulation of drug-loaded QDs in the pathological focus, its simultaneous visualization and targeted therapeutic influence occur. One of the serious limitations of the use of QDs in medicine is their potential toxicity, especially when the nanocrystal material contains elements such as cadmium or plumbum. Therefore, it is promising to develop labels based on QDs of relatively less toxic semiconductors of group I-III-VI, such as CuInS2 and AgInS2. In this study, biodistribution and biocompatibility of QDs based on the AgInS2 compound with a ZnS shell (ZAIS) are considered. In the study of biodistribution, the accumulation of QDs in organs such as liver, lungs, heart and kidneys was revealed. It was shown that QDs in the dose range from 2 • 10–7 to 4 • 10–6 M/L at intravenous administration in rats does not have a significant effect on body mass dynamics and basic hematological parameters for 30 days. Thus, ZAIS QDs can be used to visualize tissues and organs in various pathological processes, and immobilization of the drugs on their surface will allow to approach their application for theranostics.
VIEWS 4694
Parkinson disease is one of the common age-related motor neurodegenerative diseases, in which dopamine neurons degeneration is considered to be pathognomic for the development of motor disfunction. Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family, which is considered to be a key regulator of neuronal plasticity. BDNF, being a large molecule, does not pass through the blood-brain barrier (BBB). Synthetic polymer nanoparticles (NP), covered by surfactant, provide the phenomenon of “Trojan hoarse” and enable BDNF to penetrate into the brain tissue. For modelling of parkinsonism we used an intraperitoneal (i.p.) injection of neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) which was injected to the C57BL/6 mice with subsequest treatment with normal saline (group 1), BDNF (group 2), nanoparticulate BDNF (group 3) and surfactant-coated nanoparticulate BDNF (group 4). After 90 min, 24 hours, 72 hours and 7 days manifestations of parkinsonism were evaluated using behavioural tests of open field, rota-rod, assessment of the tremor, length of the body and pace. At the end of experiment the brain was sampled for histological evaluation of changes in the striatum and midbrain and concentration of BDNF in the brain tissues. The results of the experiments demonstrated that nanoparticulate BDNF covered with surfactant significanltly reduced rigidity of the skeletal muscles, oligokinesia and tremor, and also significantly increased BDNF concentration in the brain tissues.
VIEWS 4580
Aurumacryl is an incomplete metal salt of poly(acrylic acid) that exhibits hemostatic activity and inhibits the growth of transplantable carcinomas in vivo. The samples of aurumacryl synthesized following the original technique are insufficiently soluble, which complicates the study of the mechanisms involved in their synthesis and underlying their cytotoxic effect. The aim of this work was to study the impact of the following factors on aurumacryl properties: the molecular weight of the polyacrylate polymer in a range between 2 and 1,000 kDa, the presence of a counterion H+ or Na+, the molar ratio of AuCl– to the polyacrylate polymer (1 : 5 and 1 : 10), the total concentration of the polyacrylate polymer during synthesis (0.1 and 3%), and the type of drying (lyophilization). By comparing the cytotoxicity of aurumacryl samples with significantly different molar ratio of gold ions to the polyacrylate polymer against human breast carcinoma cells (MCF-7), we established that the proportion of the polymer and its molecular weight in the sample do not affect the biological properties of the synthesized substance. Using UV spectroscopy, we revealed that the concentration of Au (III) ions in aurumacryl determines its cytotoxicity.
VIEWS 4565