Biology subjects

Nekounam, H.

Publications and source records attributed to Nekounam, H..

5 recordsLinked to original sources

bioRxiv2024

Investigation and optimization the effect of electrical stimulation parameters on the differentiation of human adipose mesenchymal stem cells into neurons-like cells on carbon nanofibers

BackgroundNeurodegenerative diseases are among the most challenging diseases because neuron cells are not able to regenerate spontaneously. Tissue engineering is one of the most promising stem cell-based therapies. Controlling stem cell differentiation is a very crucial aspect of tissue engineering. MethodsIn this study, carbon nanofibers with an average diameter of 181{+/-}45 nm were prepared as a conductive scaffold based on the electrospinning method and subsequent thermal processing. Scaffold structure characterization were performed with XRD, Raman and Electrical conductivity tests. A homemade device was prepared to transmit electrical current to cells seeded on the scaffold in a culture plate. Various current parameters such as current intensity, frequency, waveform, daily shock duration, and shock period on adipose mesenchymal stem cells were examined for differentiation into neuronal cells. SPSS software and the one-way analysis of variance (ANOVA) was used as statistical analysis. ResultsCharacterization tests confirmed the formation of the carbon and crystallite structure with the electrical conductivity . Current with 1500 uA intensity, 500Hz frequency, and square waveform were selected as the optimal current parameters. It was found that the daily and periodic increase in shock time leads to an increase in the expression of neural and glial genes. A comparison of groups with real-time PCR and immunofluorescence of nestin, Map2, TubB3, and GFAPgenes was evaluated. ConclusionsThere are a variety of chemical and physical methods to control cell behavior, one of which is electrical stimulation. Conductive scaffolding is required for direct electrical stimulation of cells. The results showed that the method based on electrical stimulation can well cause neural differentiation, and considering the problems in preparing and maintaining chemical differentiation agents, it can be used practically. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=126 SRC="FIGDIR/small/593090v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@159d415org.highwire.dtl.DTLVardef@72bbb3org.highwire.dtl.DTLVardef@811222org.highwire.dtl.DTLVardef@1cda185_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical abstract:C_FLOATNO stages of scaffold preparation and electrical stimulation of stem cells C_FIG

bioengineering↗

bioRxiv2022

Carbon nanofibers fabrication, surface modifications, and application as the innovative substrate for electrical stimulation of neural cell differentiation

Engineered nanostructures are innovative and precisely designed, synthesized, and tailored with outstanding physicochemical properties that can be applied as the game-changer in neural tissue engineering. The present study aimed to develop an innovative approach based on electrical stimulation through a conductive scaffold to differentiate neural cells from human adipose mesenchymal stem cells without the use of a specific environment for neural differentiation. Electrospun carbon nanofibers (CNFs) were obtained using heat treatment of polyacrylonitrile nanofibers and treated by nitric acid, ethylenediamine, and oxygen Plasma. SEM imaging revealed that the treated nanofibers have s diameter in the range of 120-200 nm and the treatment did not significantly change the CNFs diameter. The FTIR results showed that the treatments were able to introduce COOH, OH, and NH2 functional groups on the CNFS surface. The XRD and Raman analysis showed that the plasma treatment induced the lowest structural changes in the CNFs microstructure. The biocompatibility assessments showed that the pristine and treated CNFs were non-toxic induced proliferative effect on human adipose-derived mesenchymal stem cells. The electrical stimulation (1.5 mA current with a frequency of 500 Hz and CMOS waveform for 7 days 10 min each day) induced the expression of neural genes and proteins by the cells cultured on the treated CNFs. The Plasma-treated CNFs mediated the highest differentiation outcome. These results indicate that electrospun CNFs can be applied as the innovative interface applicable for neural tissue regeneration under electrical stimulation. Research highlightsO_LICNFs were fabricated from PAN nanofibers C_LIO_LIDifferent amounts of ZnONPs were incorporated into or sprayed on CNF C_LIO_LIincreasing in ZnONP amount decreased conductivity, surface wettability was improved by [~]19-33%. C_LIO_LIAlso, FTIR, XRD, and Raman analyses proved that the presence of ZnONP improved structure formation with lower defect density C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=96 SRC="FIGDIR/small/512333v1_figS1.gif" ALT="Figure 1"> View larger version (23K): org.highwire.dtl.DTLVardef@a6eb07org.highwire.dtl.DTLVardef@9040e8org.highwire.dtl.DTLVardef@955840org.highwire.dtl.DTLVardef@d4fa0e_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOSchematic 1.C_FLOATNO The applied electrical stimulation setup C_FIG

bioengineering↗

bioRxiv2021

Preparation of cationized albumin nanoparticles loaded indirubin by high pressure hemogenizer

Indirubin can be applied as an anti-cancer drug for inhibition of brain tumors. However, its performance is reduced due to hydrophobicity. In this study, we synthesized cationic human serum albumin (CHSA) nanoparticle by a new hybrid approach for improvement the surface chemistry of albumin and investigate the amount of indirubin loaded CHSA nanoparticle. In this study, the generated mechanical force from a high-pressure homogenizer (HPH) was used to make nanoparticles with a certain size with narrow polydispersity. The results indicated that the size of indirubin loaded CHSA nanoparticles were 130 nm and their zeta potential were +9. Besides, the encapsulation efficiency and drug loading capacity were found to be 85% and 5.8 %, respectively. To the best to our knowledge, this is the first time that indirubin has been used in albumin nanoparticles. In this study, indirubin loaded CHSA nanoparticles was shown can be a potential candidate for drug delivery in the treatment of glioblastoma. Moreover, the cationized form allows the chemical agent to be transmitted to the brain.

cancer biology↗

bioRxiv2020

Electro-conductive carbon nanofibers containing ferrous sulfate for bone tissue engineering

The application of electroactive scaffolds can be promising for bone tissue engineering applications. In the current paper, we aimed to fabricate an electro-conductive scaffold based on carbon nanofibers (CNFs) containing ferrous sulfate. FeSO4{middle dot}7H2O salt with different concentrations 5, 10, and 15 wt%, were blended with polyacrylonitrile (PAN) polymer as the precursor and converted to Fe2O3/CNFs nanocomposite by electrospinning and heat treatment. The characterization was conducted using SEM, EDX, XRD, FTIR, and Raman methods. The results showed that the incorporation of Fe salt did not induce an adverse effect on the nanofibers morphology. EDX analysis confirmed that the Fe are uniformly dispersed throughout the CNF mat. FTIR spectroscopy showed the interaction of Fe salt with PAN polymer. Raman spectroscopy showed that the incorporation of FeSO4{middle dot}7H2O reduced the ID/IG ratio, indicating more ordered carbon in the synthesized nanocomposite. Electrical resistance measurement depicted that, although the incorporation of ferrous sulfate reduced the electrical conductivity, the conductive is suitable for electrical stimulation. The in vitro studies revealed that the prepared nanocomposites were cytocompatible and only negligible toxicity (less than 10%) induced by CNFs/Fe2O3 fabricated from PAN FeSO4{middle dot}7H2O 15%. These results showed that the fabricated nanocomposites could be applied as the bone tissue engineering scaffold.

bioinformatics↗

bioRxiv2020

Simple and Robust Fabrication and Characterization of Conductive Carbonized Nanofibers Loaded with Gold Nanoparticles for Bone Tissue Engineering Applications

Bone tissue engineering is a new and applicable emerging approach to repair the bone defects. Electrical conductive scaffolds through a physiologically relevant physical signaling, electrical stimulation, has shown a highly promise in this approach. In this paper, we fabricated carbon nanofiber/gold nanoparticle (CNF/GNP) conductive scaffolds using two distinct methods; blending electrospinning in which GNP were blended with electrospinning solution, and electrospinning/electrospraying in which GNP was electrosprayed simultaneously with electrospinning. The obtained electrospun mats underwent stabilization/carbonization process. The scaffolds were characterized by SEM, XRD, FT-IR and Raman spectroscopy. SEM characterizations showed improved morphology and a slight decrease in the diameter of the spinned and sprayed nanofibers (from 178.66 {+/-} 38.40 nm to 157.94 {+/-} 24.14 nm and 120.81 {+/-} 13.77 nm, respectively), while XRD analysis confirmed the crystal structure of the nanofibers. Raman spectroscopy revealed enhancement in the graphitization of the structure, and the electrical conductivity of the structure improved by up to 29.2% and 81% in electrospraying and blending electrospinning modes, respectively. Indirect MTT and LDH toxicity assays directly were performed to assess MG63 cell toxicity, but no significant toxicity was observed and the scaffolds did not adversely affect cell proliferation. It can be concluded this structure have potential for bone tissue engineering applications. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=80 SRC="FIGDIR/small/013383v2_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@1ac84f1org.highwire.dtl.DTLVardef@14bef2dorg.highwire.dtl.DTLVardef@438261org.highwire.dtl.DTLVardef@24e1b4_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗