In Vitro and In Silico Investigation of Water-Soluble Fullerenol C60(OH)24: Bioactivity and Biocompatibility

Solubilizer of bacterial origin surfactin increases the biological activity of C60 fullerene

Currently, there exists conflicting data regarding the biological activity of unmodified fullerene C60. Various sources report its toxicity, geroprotective activity, and potential interaction with DNA. Contradictory findings regarding the toxicity of C60 may arise from the use of toxic solvents, as well as the influence of bioavailability and bioactivity on the preparation conditions of C60 suspensions. Furthermore, the microbiota of experimental animals can impact geroprotective activity results by releasing surfactants that facilitate substance penetration through the cell membrane. In this study, we selected conditions for solubilizing fullerene C60 in a solution of surfactin, a surfactant of bacterial origin, as well as in a 2% aqueous solution of TWEEN 80, employing ultrasound. Through bioluminescent analysis using lux biosensors in Escherichia coli MG1655, we observed that C60 in surfactin reduced induced genotoxic and oxidative stress. Given that surfactin enhances membrane permeability to fullerene C60, suspensions of fullerene in designated concentrations of surfactin can be regarded as a DNA protector and antioxidant, warranting further investigation as a promising component of novel drugs.

Capacity of fullerenols to modulate neurodegeneration induced by ferroptosis: Focus on multiple sclerosis

Multiple sclerosis is an inflammatory disease of the central nervous system (CNS), characterized by oligodendrocyte loss and demyelination of axons leading to neurodegeneration and severe neurological disability. Despite the existing drugs that have immunomodulatory effects an adequate therapy that slow down or stop neuronal death has not yet been found. Oxidative stress accompanied by excessive release of iron into the extracellular space, mitochondrial damage and lipid peroxidation are important factors in the controlled cell death named ferroptosis, latterly recognized in MS. As the fullerenols exhibit potent antioxidant activity, recent results imply that they could have protective effects by suppressing ferroptosis. Based on the current knowledge we addressed the main mechanisms of the protective effects of fullerenols in the CNS in relation to ferroptosis. Inhibition of inflammation, iron overload and lipid peroxidation through the signal transduction mechanism of Nuclear Factor Erythroid 2-Related Factor 2 (NRF2), chelation of heavy metals and free radical scavenging using fullerenols are proposed as benefitial strategy preventing MS progression. Current review connects ferroptosis molecular targets and important factors of MS progression, with biomedical properties and mechanisms of fullerenols' actions, to propose new treatment strategies that could be addaptobale in other neurodegenerative diseases.

The impact of fullerenol nanoparticles on the growth of toxigenic Aspergillus flavus and aflatoxins production in vitro and in corn flour

Antifungal and antimycotoxigenic activity of fullerenol nanoparticles (FNPs) were investigated on Aspergillus flavus growth isolated from a real food sample and aflatoxins (AFs) (AFB1 and AFB2 ) production. The final FNPs concentrations in in vitro and in commercial corn flour after the stationary incubation period of 7 and 14 days were in the range 0.16-80 µg/mL and 0.16-80 µg/g, respectively. Nanocharacterization of FNPs revealed an average size of 5-20 nm and a zeta potential of -35 mV. The highest degree of A. flavus mycelium growth inhibition (28%) after 7 days was observed for applied FNP concentration of 8.0 µg/mL, while after 14 days FNP concentration of 0.32 µg/mL led to the maximal inhibition of A. flavus mycelium growth (36%). Spearman's correlations analysis revealed a strong positive correlation between AFB1 and AFB2 concentrations in YES broth after 7 (R = 0.994, p < 0.05) and 14 days (R = 0.976), as well as between AFs concentrations and A. flavus mycelium mass after 7 (R = 0.786 for AFB1 and R = 0.766 for AFB2 ) and 14 days (R = 0.810 for AFB1 and R = 0.833 for AFB2 ). Paired samples t-test showed the existence of a statistically significant difference (p < 0.05) between the produced AFs concentrations after the incubation of 7 and 14 days. Regarding the artificially inoculated corn flour the lower applied FNP concentrations (0.16-0.8 µg/g) achieved a reduction of AFB1 up to 42% and 60% after 7 and 14 days, respectively.

Application of carbon nanostructures in biomedicine: realities, difficulties, prospects

The review systematizes data on the wide possibilities of practical application of carbon nanostructures. Much attention is paid to the use of carbon nanomaterials in medicine for the visualization of tumors during surgical interventions, in the creation of cosmetics, as well as in agriculture in the creation of fertilizers. Additionally, we demonstrate trends in research in the field of carbon nanomaterials with a view to elaborating targeted drug delivery systems. We also show the creation of nanosized medicinal substances and diagnostic systems, and the production of new biomaterials. A separate section is devoted to the difficulties in studying carbon nanomaterials. The review is intended for a wide range of readers, as well as for experts in the field of nanotechnology and nanomedicine.

C60 adduct with L-arginine as a promising nanomaterial for treating cerebral ischemic stroke

The work aimed to investigate the biocompatibility and biological activity of the water-soluble fullerene adduct C60-Arg. It was found that the material is haemocompatible, is not cyto- and genotoxic, possesses pronounced antioxidant activity. Additionally, this paper outlines the direction of application of water-soluble fullerene adducts in the creation of neuroprotectors. It has been suggested that a putative mechanism of the protective action of the C60-Arg adduct is associated with its antioxidant properties, the ability to penetrate the blood-brain barrier, and release nitrogen monoxide as a result of the catabolism of L-arginine residues, which promote vascular relaxation. The action of the C60-Arg adduct was compared with the action of such an antioxidant as Edaravone, which is approved in Japan for the treatment of ischemic and haemorrhagic strokes.

Polyhydroxylated Fullerene C60(OH)40 Nanofilms Promote the Mesenchymal-Epithelial Transition of Human Liver Cancer Cells via the TGF-β1/Smad Pathway

Background

The various growth factors change the phenotype of neoplastic cells from sedentary (epithelial) to invasive (mesenchymal), which weaken intercellular connections and promote chemotaxis. It can be assumed that the use of anti-inflammatory polyhydroxyfull nanofilms will restore the sedentary phenotype of neoplastic cells in the primary site of the tumor and, consequently, increase the effectiveness of the therapy.

Methods

The studies were carried out on liver cancer cells HepG2, C3A and SNU-449, and non-cancer hepatic cell line THLE-3. Transforming growth factor (TGF), epidermal growth factor and tumor necrosis factor were used to induce the epithelial-mesenchymal transition. C60(OH)40 nanofilm was used to induce the mesenchymal-epithelial transition. Obtaining an invasive phenotype was confirmed on the basis of changes in the morphology using inverted light microscopy. RT-PCR was used to confirm mesenchymal or epithelial phenotype based on e-cadherin, snail, vimentin expression or others. Water colloids at a concentration of 100 mg/L were used to create nanofilms of fullerene, fullerenol, diamond and graphene oxide. The ELISA test for the determination of TGF expression and growth factor antibody array were used to select the most anti-inflammatory carbon nanofilm. Mitochondrial activity and proliferation of cells were measured by XTT and BrdU tests.

Results

Cells lost their natural morphology of cells growing in clusters and resembled fibroblast cells after adding a cocktail of factors. Among the four allotropic forms of carbon tested, only the C60(OH)40 nanofilm inhibited the secretion of TGF in all the cell lines used and inhibited the secretion of other factors, including insulin-like growth factor system. Nanofilm C60(OH)40 was non-toxic to liver cells and inhibited the TGF-β1/Smad pathway of invasive cells treated with the growth factor cocktail.

Conclusion

The introduction of an anti-inflammatory, nontoxic component that can induce the mesenchymal-epithelial transition of cancer cells may represent a future adjuvant therapy after tumor resection.

Quenching of Protein Fluorescence by Fullerenol C60(OH)36 Nanoparticles

The effect of the interaction between fullerenol C60(OH)36 (FUL) and alcohol dehydrogenase (ADH) from Saccharomyces cerevisiae and human serum albumin (HSA) was studied by absorption spectroscopy, fluorescence spectroscopy, and time-resolved fluorescence spectroscopy. As shown in the study, the fluorescence intensities of ADH and HSA at excitation wavelengths λex = 280 nm (Trp, Tyr) and λex = 295 nm (Trp) are decreased with the increase in the FUL concentration. The results of time-resolved measurements indicate that both quenching mechanisms, dynamic and static, are present. The binding constant Kb and the number of binding sites were obtained for HSA and ADH. Thus, the results indicated the formation of FUL complexes and proteins. However, the binding of FUL to HSA is much stronger than that of ADH. The transfer of energy from the protein to FUL was also proved.

Biocompatibility, antioxidant activity and collagen photoprotection properties of C60 fullerene adduct with L-methionine

Functionalization of the fullerene core with amino acids has become a new and promising direction in the field of nanochemistry. The biologic activity of water-soluble fullerene derivatives is based on such properties as lipophilicity, electron deficiency and photosensitivity. The complex of above-mentioned properties can be used to develop protection of biomolecules (in particular, proteins) from external physical and chemical influences. Thus, development and up-scaling of synthesis procedures, as well as investigation of the biological properties of these derivatives, are extremely important. This paper presents new data on the biocompatibility studies of C₆₀ fullerene adduct with L-methionine (C₆₀[C₅H₁₁NO₂S]₃; C₆₀-Met). Antiradical activity, binding to human serum albumin (HSA), collagen and deoxyribonucleic acid (DNA), hemocompatibility, photodynamic properties, genotoxicity and cytotoxicity were studied. In addition, it was found that C₆₀-Met increases the photostability of the collagen molecule, and this effect is dose-dependent.

The Effect of Fullerenol C60(OH)36 on the Antioxidant Defense System in Erythrocytes

Background: Fullerenols (water-soluble derivatives of fullerenes), such as C60(OH)36, are biocompatible molecules with a high ability to scavenge reactive oxygen species (ROS), but the mechanism of their antioxidant action and cooperation with endogenous redox machinery remains unrecognized. Fullerenols rapidly distribute through blood cells; therefore, we investigated the effect of C60(OH)36 on the antioxidant defense system in erythrocytes during their prolonged incubation. Methods: Human erythrocytes were treated with fullerenol at concentrations of 50-150 µg/mL, incubated for 3 and 48 h at 37 °C, and then hemolyzed. The level of oxidative stress was determined by examining the level of thiol groups, the activity of antioxidant enzymes (catalase, glutathione peroxidase, glutathione reductase, and glutathione transferase), and by measuring erythrocyte microviscosity. Results: The level of thiol groups in stored erythrocytes decreased; however, in the presence of higher concentrations of C60(OH)36 (100 and 150 µg/mL), the level of -SH groups increased compared to the control. Extending the incubation to 48 h caused a decrease in antioxidant enzyme activity, but the addition of fullerenol, especially at higher concentrations (100-150 µg/mL), increased its activity. We observed that C60(OH)36 had no effect on the microviscosity of the interior of the erythrocytes. Conclusions: In conclusion, our results indicated that water-soluble C60(OH)36 has antioxidant potential and efficiently supports the enzymatic antioxidant system within the cell. These effects are probably related to the direct interaction of C60(OH)36 with the enzyme that causes its structural changes.