Enhanced Cellular Activity on Conducting Polymer

This chapter includes detailed review of the research undertaken with conducting polymer (CP) based composites with chitosan (Ch) for tissue engineering till date. The beneficial role of electrically conductive biomaterials has been discussed with the possible strategies to overcome the shortcomings of CP alone through blending with Ch due to its excellent biocompatibility, biodegradability, and bioactivity. Additionally, this embodiment deals with the optimization and characterization of electrically conductive, biocompatible and biodegradable Polyaniline: Chitosan (PAni:Ch) nanocomposites as cell culture substrates for MDA-MB-231 and NIH 3T3 fibroblast in order to examine the combined effect of nanofiber structure and surface modification on cell-biomaterial interactions. The nanocomposites were further checked as a conductive scaffold for electrical stimulation of a neuronal model PC12 cell line in order to explore the potential of the materials in neural tissue engineering.

Retraction Note: Suppressor capacity of copper nanoparticles biosynthesized using Crocus sativus L. leaf aqueous extract on methadone-induced cell death in adrenal phaeochromocytoma (PC12) cell line

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1038/s41598-020-77741-4.

Hydroalcoholic Extract of Cuscuta Epithymum Enhances Pentobarbitalinduced Sleep: Possible Involvement of GABAergic System

Background: Insomnia is the most common sleep disorder. The present study was undertaken to evaluate the sedative-hypnotic potential of hydroalcoholic extract (HAE) of Cuscuta epithymum and its fractions. Methods: HAE and its fractions including: water fraction (WF), ethyl acetate fraction (EAF) and n-hexan fraction (NHF) were i.p administered to male mice and 30 min later pentobarbital (30 mg/kg, i.p.) was injected to induce sleep. Then the latent period and continuous sleeping time were recorded. Besides, 30 mins after administration of HAE motor coordination (rota-rod test) were assessed. Additionally, LD50 of HAE was determined and the possible neurotoxicity of the extract was tested on neural PC12 cells. Results: The HAE and NHF decreased the latency of sleep and significantly increased the duration of sleep induced by pentobarbital. These effects of C. epithymum were reversed by flumazenil. HAE did not affect the animals’ performance on the rotarod test. The LD50 value for HAE was found to be 4.8 g/kg. HAE and its fractions had no toxicity effect on the viability of PC12-cell line. Conclusion: The results of the present study indicate that the HAE and NHF have significant sedativehypnotic effects in mice without major toxic effect and that the benzodiazepine receptors are involved in the sedative-hypnotic effects of this plant.

PC12 Cell Line: Cell Types, Coating of Culture Vessels, Differentiation and Other Culture Conditions

The PC12 cell line is one of the most commonly used in neuroscience research, including studies on neurotoxicity, neuroprotection, neurosecretion, neuroinflammation, and synaptogenesis. Two types of this line are available in the ATCC collection: traditional PC12 cells grown in suspension and well-attached adherent phenotype. PC12 cells grown in suspension tend to aggregate and adhere poorly to non-coated surfaces. Therefore, it is necessary to modify the surface of culture vessels. This paper aims to characterise the use of two distinct variants of PC12 cells as well as describe their differentiation and neuronal outgrowth with diverse NGF concentrations (rat or human origin) on various surfaces. In our study, we evaluated cell morphology, neurite length, density and outgrowth (measured spectrofluorimetrically), and expression of neuronal biomarkers (doublecortin and NeuN). We found that the collagen coating was the most versatile method of surface modification for both cell lines. For adherent cells, the coating was definitely less important, and the poly-d-lysine surface was as good as collagen. We also demonstrated that the concentration of NGF is of great importance for the degree of differentiation of cells. For suspension cells, we achieved the best neuronal characteristics (length and density of neurites) after 14 days of incubation with 100 ng/mL NGF (change every 48 h), while for adherent cells after 3–5 days, after which they began to proliferate. In the PC12 cell line, doublecortin (DCX) expression in the cytoplasm and NeuN in the cell nucleus were found. In turn, in the PC12 Adh line, DCX was not expressed, and NeuN expression was located in the entire cell (both in the nucleus and cytoplasm). Only the traditional PC12 line grown in suspension after differentiation with NGF should be used for neurobiological studies, especially until the role of the NeuN protein, whose expression has also been noted in the cytoplasm of adherent cells, is well understood.