## 3 Discussion
Filament-shaped particles had a longer circulation half-life in vivo compared with prototypical spherical particles after intravenous injection [50; 51]. With regard to the removal of nanoparticles of various shapes from the body, clear correlations have been established. The released amounts of degradation products of long and short rods were noticeably less than the number of spherical nanoparticles 2-h after oral administration [9]. The filamentous form of nanostructures has a number of advantages for use in neuroscience. It has been shown for carbon nanotubes that the structural features and dimensions are very similar to many elements of the neuronal network (ion channels, signaling proteins, and elements of the neuronal cytoskeleton), which allows them to be used to regulate the functional activity of neuroglial networks [52]. Carbon nanotubes have been shown to enhance neuronal electrical signaling [53], decrease astrocyte formation, macrophage density [54], and have been shown to increase the differentiation of progenitor cells to neurons [55]. Interestingly, carbon threads [56] were also compatible with neural cells as demonstrated by culturing hippocampal neurons and PC12 cells on them. After a week in culture, neurite outgrowth on the nanorods surface showed neuron-specific labeling (\(\beta\)111 tubulin staining), indicating the biocompatibility of these nanorods for the construction of electrodes or nanowires in implantable devices [57]. All these effects on the excitation of neuronal networks undoubtedly occur due to the activation of the Ca\({}^{2+}\) signaling system of neurons and astrocytes. In our experiments, it was found that the use of SeNrs in an acute experiment led to the generation of Ca\({}^{2+}\) signals of astrocytes in the form of a gradual increase in the base concentration of [Ca\({}^{2+}\)]\({}_{i}\), which is similar in shape and amplitude to the action of spherical selenium nanoparticles (SeNPs) with a diameter of 50 nm. At the same time, the EC50 for activation of the Ca\({}^{2+}\) signaling system of astrocytes under the action of SeNrs is higher (4.9 \(\mu\)g/mL), compared to spherical SeNPs with a diameter of 50 nm (1 \(\mu\)g/mL) and 400 nm (2.4 \(\mu\)g/mL) [28]. Thus, the shape of nanoparticles in the form of SeNrs affects the dose dependence of the activation of Ca\({}^{2+}\) signals of astrocytes, which also determines the physiological effects of nanoselenium. It turned out that preincubation of cortical astrocytes with SeNrs protects them from death under the action of OGD both at a concentration of 1 \(\upmu\)g/mL and 5 \(\upmu\)g/mL, suppressing the global increase in [Ca\({}^{2+}\)]i and cell necrosis. Molecular selenium [58; 59] and spherical nanoselenium [60; 23; 61] clearly show anti-apoptotic and anti-inflammatory effects on brain tissue. However, there are no such works for nanoselenium in the form of nanorods. At the same time, there are single works showing the protective effect of materials in the form of nanofibers on tissue. Poly(\(\varepsilon\)-caprolactone)/polysialic acid hybrid nanofibers scaffold encapsulating glucocorticoid methyl-prednisolone has been shown to suppress TNF-\(\alpha\) and interleukin-6 IL-6 release by inhibiting ionized calcium-binding adapter molecule 1 (Iba1)-positive microglia/macrophage activation and reduces apoptosis-associated Caspase-3 protein expression in the spinal cord injury model [62]. In addition, the wound healing effects of structures in the form of nanofibers have been established. Ag-nanofibers upregulated molecules implicated in the TGF-\(\beta\)1/Smad signaling pathway, hence boosting collagen synthesis and improving wound healing by upregulating TGF-\(\beta\)1 secretion and activating the TGF-\(\beta\)1/Smad signaling pathway during the early stages of wound healing, boosting the adhesion and proliferation of fibroblasts [63]. Nanoselenium in the form of nanorods caused an increase in the baseline and OGD/R-induced expression of the antioxidant gene _Nrf2_, anti-inflammatory interleukin 10 (IL-10), and _Hf2a_.