Effect of C60 Fullerene on Recovery of Muscle Soleus in Rats after Atrophy Induced by Achillotenotomy.

Biomechanical and biochemical changes in the muscle soleus of rats during imitation of hind limbs unuse were studied in the model of the Achilles tendon rupture (Achillotenotomy). Oral administration of water-soluble C60 fullerene at a dose of 1 mg/kg was used as a therapeutic agent throughout the experiment. Changes in the force of contraction and the integrated power of the muscle, the time to reach the maximum force response, the mechanics of fatigue processes development, in particular, the transition from dentate to smooth tetanus, as well as the levels of pro- and antioxidant balance in the blood of rats on days 15, 30 and 45 after injury were described. The obtained results indicate a promising prospect for C60 fullerene use as a powerful antioxidant for reducing and correcting pathological conditions of the muscular system arising from skeletal muscle atrophy.

C60 fullerene attenuates muscle force reduction in a rat during fatigue development.

C60 fullerene (C60) as a nanocarbon particle, compatible with biological structures, capable of penetrating through cell membranes and effectively scavenging free radicals, is widely used in biomedicine. A protective effect of C60 on the biomechanics of fast (m. gastrocnemius) and slow (m. soleus) muscle contraction in rats and the pro- and antioxidant balance of muscle tissue during the development of muscle fatigue was studied compared to the same effect of the known antioxidant N-acetylcysteine (NAC). C60 and NAC were administered intraperitoneally at doses of 1 and 150 mg kg-1, respectively, daily for 5 days and 1 h before the start of the experiment. The following quantitative markers of muscle fatigue were used: the force of muscle contraction, the level of accumulation of secondary products of lipid peroxidation (TBARS) and the oxygen metabolite H2O2, the activity of first-line antioxidant defense enzymes (superoxide dismutase (SOD) and catalase (CAT)), and the condition of the glutathione system (reduced glutathione (GSH) content and the activity of the glutathione peroxidase (GPx) enzyme). The analysis of the muscle contraction force dynamics in rats against the background of induced muscle fatigue showed, that the effect of C60, 1 h after drug administration, was (15-17)% more effective on fast muscles than on slow muscles. A further slight increase in the effect of C60 was revealed after 2 h of drug injection, (7-9)% in the case of m. gastrocnemius and (5-6)% in the case of m. soleus. An increase in the effect of using C60 occurred within 4 days (the difference between 4 and 5 days did not exceed (3-5)%) and exceeded the effect of NAC by (32-34)%. The analysis of biochemical parameters in rat muscle tissues showed that long-term application of C60 contributed to their decrease by (10-30)% and (5-20)% in fast and slow muscles, respectively, on the 5th day of the experiment. At the same time, the protective effect of C60 was higher compared to NAC by (28-44)%. The obtained results indicate the prospect of using C60 as a potential protective nano agent to improve the efficiency of skeletal muscle function by modifying the reactive oxygen species-dependent mechanisms that play an important role in the processes of muscle fatigue development.

Single-Walled Carbon Nanotubes Inhibit TRPC4-Mediated Muscarinic Cation Current in Mouse Ileal Myocytes.

Single-walled carbon nanotubes (SWCNTs) are characterized by a combination of rather unique physical and chemical properties, which makes them interesting biocompatible nanostructured materials for various applications, including in the biomedical field. SWCNTs are not inert carriers of drug molecules, as they may interact with various biological macromolecules, including ion channels. To investigate the mechanisms of the inhibitory effects of SWCNTs on the muscarinic receptor cation current (mICAT), induced by intracellular GTPγs (200 µM), in isolated mouse ileal myocytes, we have used the patch-clamp method in the whole-cell configuration. Here, we use molecular docking/molecular dynamics simulations and direct patch-clamp recordings of whole-cell currents to show that SWCNTs, purified and functionalized by carboxylation in water suspension containing single SWCNTs with a diameter of 0.5-1.5 nm, can inhibit mICAT, which is mainly carried by TRPC4 cation channels in ileal smooth muscle cells, and is the main regulator of cholinergic excitation-contraction coupling in the small intestinal tract. This inhibition was voltage-independent and associated with a shortening of the mean open time of the channel. These results suggest that SWCNTs cause a direct blockage of the TRPC4 channel and may represent a novel class of TRPC4 modulators.

C60 fullerene against SARS-CoV-2 coronavirus: an in silico insight.

Based on WHO reports the new SARS-CoV-2 coronavirus is currently widespread all over the world. So far > 162 million cases have been confirmed, including > 3 million deaths. Because of the pandemic still spreading across the globe the accomplishment of computational methods to find new potential mechanisms of virus inhibitions is necessary. According to the fact that C60 fullerene (a sphere-shaped molecule consisting of carbon) has shown inhibitory activity against various protein targets, here the analysis of the potential binding mechanism between SARS-CoV-2 proteins 3CLpro and RdRp with C60 fullerene was done; it has resulted in one and two possible binding mechanisms, respectively. In the case of 3CLpro, C60 fullerene interacts in the catalytic binding pocket. And for RdRp in the first model C60 fullerene blocks RNA synthesis pore and in the second one it prevents binding with Nsp8 co-factor (without this complex formation, RdRp can't perform its initial functions). Then the molecular dynamics simulation confirmed the stability of created complexes. The obtained results might be a basis for other computational studies of 3CLPro and RdRp potential inhibition ways as well as the potential usage of C60 fullerene in the fight against COVID-19 disease.

Protective Effect of Water-Soluble C60 Fullerene Nanoparticles on the Ischemia-Reperfusion Injury of the Muscle Soleus in Rats.

The biomechanical parameters of muscle soleus contraction in rats and their blood biochemical indicators after the intramuscular administration of water-soluble C60 fullerene at doses of 0.5, 1, and 2 mg/kg 1 h before the onset of muscle ischemia were investigated. In particular, changes in the contraction force of the ischemic muscle soleus, the integrated power of the muscle, the time to achieve the maximum force response, the dynamics of fatigue processes, and the parameters of the transition from dentate to smooth tetanus, levels of creatinine, creatine kinase, lactate and lactate dehydrogenase, and parameters of prooxidant-antioxidant balance (thiobarbituric acid reactive substances, hydrogen peroxide, and reduced glutathione and catalase) were analyzed. The positive therapeutic changes in the studied biomechanical and biochemical markers were revealed, which indicate the possibility of using water-soluble C60 fullerenes as effective prophylactic nanoagents to reduce the severity of pathological conditions of the muscular system caused by ischemic damage to skeletal muscles.

Analysis of Biomechanical Parameters of Muscle Soleus Contraction and Blood Biochemical Parameters in Rat with Chronic Glyphosate Intoxication and Therapeutic Use of C60 Fullerene.

The widespread use of glyphosate as a herbicide in agriculture can lead to the presence of its residues and metabolites in food for human consumption and thus pose a threat to human health. It has been found that glyphosate reduces energy metabolism in the brain, its amount increases in white muscle fibers. At the same time, the effect of chronic use of glyphosate on the dynamic properties of skeletal muscles remains practically unexplored. The selected biomechanical parameters (the integrated power of muscle contraction, the time of reaching the muscle contraction force its maximum value and the reduction of the force response by 50% and 25% of the initial values during stimulation) of muscle soleus contraction in rats, as well as blood biochemical parameters (the levels of creatinine, creatine phosphokinase, lactate, lactate dehydrogenase, thiobarbituric acid reactive substances, hydrogen peroxide, reduced glutathione and catalase) were analyzed after chronic glyphosate intoxication (oral administration at a dose of 10 µg/kg of animal weight) for 30 days. Water-soluble C60 fullerene, as a poweful antioxidant, was used as a therapeutic nanoagent throughout the entire period of intoxication with the above herbicide (oral administration at doses of 0.5 or 1 mg/kg). The data obtained show that the introduction of C60 fullerene at a dose of 0.5 mg/kg reduces the degree of pathological changes by 40-45%. Increasing the dose of C60 fullerene to 1 mg/kg increases the therapeutic effect by 55-65%, normalizing the studied biomechanical and biochemical parameters. Thus, C60 fullerenes can be effective nanotherapeutics in the treatment of glyphosate-based herbicide poisoning.

Water-Soluble Pristine C60 Fullerene Inhibits Liver Alterations Associated with Hepatocellular Carcinoma in Rat.

Excessive production of reactive oxygen species is the main cause of hepatocellular carcinoma (HCC) initiation and progression. Water-soluble pristine C60 fullerene is a powerful and non-toxic antioxidant, therefore, its effect under rat HCC model and its possible mechanisms were aimed to be discovered. Studies on HepG2 cells (human HCC) demonstrated C60 fullerene ability to inhibit cell growth (IC50 = 108.2 µmol), to induce apoptosis, to downregulate glucose-6-phosphate dehydrogenase, to upregulate vimentin and p53 expression and to alter HepG2 redox state. If applied to animals experienced HCC in dose of 0.25 mg/kg per day starting at liver cirrhosis stage, C60 fullerene improved post-treatment survival similar to reference 5-fluorouracil (31 and 30 compared to 17 weeks) and inhibited metastasis unlike the latter. Furthermore, C60 fullerene substantially attenuated liver injury and fibrosis, decreased liver enzymes, and normalized bilirubin and redox markers (elevated by 1.7-7.7 times under HCC). Thus, C60 fullerene ability to inhibit HepG2 cell growth and HCC development and metastasis and to improve animal survival was concluded. C60 fullerene cytostatic action might be realized through apoptosis induction and glucose-6-phosphate dehydrogenase downregulation in addition to its antioxidant activity.

C60 Fullerene Governs Doxorubicin Effect on Metabolic Profile of Rat Microglial Cells In Vitro.

Background: C60 fullerenes and their derivatives are actively investigated for the use in neuroscience. Applications of these nanoscale materials require the examination of their interaction with different neural cells, especially with microglia, because these cells, like other tissue resident phagocytes, are the earliest and most sensitive responders to nanoparticles. The aim of this study was to investigate the effect of C60 fullerene and its nanocomplex with doxorubicin (Dox) on the metabolic profile of brain-resident phagocytes-microglia-in vitro. Methods: Resting microglial cells from adult male Wistar rats were used in experiments. Potential C60 fullerene targets in microglial cells were studied by computer simulation. Microglia oxidative metabolism and phagocytic activity were examined by flow cytometry. Griess reaction and arginase activity colorimetric assay were used to explore arginine metabolism. Results: C60 fullerene when used alone did not influence microglia oxidative metabolism and phagocytic activity but shifted arginine metabolism toward the decrease of NO generation. Complexation of C60 fullerene with Dox (C60-Dox) potentiated the ability of the latter to stimulate NO generation. Conclusion: The capability of C60 fullerenes used alone to cause anti-inflammatory shift of microglia arginine metabolism makes them a promising agent for the correction of neuroinflammatory processes involved in neurodegeneration. The potentiating action of C60 fullerene on the immunomodulatory effect of Dox allows us to consider the C60 molecule as an attractive vehicle for this antitumor agent.

Effect of C60 fullerene nanoparticles on the diet-induced obesity in rats.

BACKGROUND: Obesity is a growing global health problem. Since increased oxidative stress is one of the key pathological mechanisms underpinning overweight and strongly correlates with progression of obesity-related complications we hypothesized that C60 fullerene nanoparticles, due to their strong antioxidant capacity, could be the promising therapeutic agent in the treatment of this disease. Here we investigated whether the C60 fullerenes can alleviate diet-induced obesity (DIO) and metabolic impairments associated with it. METHODS: To determine the effect of C60 fullerenes on some nutritional and metabolic parameters, rats were fed either a normal diet (6.7% fat, 15.27 kJ·g-1) or a high-fat diet (38.8% fat, 28.71 kJ·g-1) for 70 days and were simultaneously treated per os with pristine C60 fullerene aqueous solution (C60FAS; 0.3 mg·kg-1 every other day) since the 28th day from the start of the experiment. RESULTS: Rats fed with high fat diet had significantly increased body mass index (BMI), levels of insulin, glucose, glycosilated hemoglobin (HbA1c) and serum pro-inflammatory cytokines compared with control rats fed with low-fat chow. C60 fullerenes normalized the metabolic parameters and partially reduced BMI in DIO animals. Pro-inflammatory cytokines (IL-1b, IL-12, INFγ) were also decreased in serum of DIO rats treated with C60 fullerenes while anti-inflammatory cytokines (IL-4, IL-10) were at the control levels. High fat diet caused the increased level of oxidative stress products, and this was accompanied by decreased activity both the superoxide dismutase and catalase, whereas the administration of C60 fullerenes markedly decreased level of oxidative stress and enhanced antioxidant enzyme activities. CONCLUSION: These data indicate that water-soluble pristine C60 fullerenes reduce chronic inflammation, restore glucose homeostasis as well as positively affects on prooxidant-antioxidant homeostasis. C60 fullerenes could be represented as a promising therapeutic agent in the treatment of obesity and its related complications.

C60 fullerene as promising therapeutic agent for correcting and preventing skeletal muscle fatigue.

BACKGROUND: Bioactive soluble carbon nanostructures, such as the C60 fullerene can bond with up to six electrons, thus serving by a powerful scavenger of reactive oxygen species similarly to many natural antioxidants, widely used to decrease the muscle fatigue effects. The aim of the study is to define action of the pristine C60 fullerene aqueous colloid solution (C60FAS), on the post-fatigue recovering of m. triceps surae in anaesthetized rats. RESULTS: During fatigue development, we observed decrease in the muscle effort level before C60FAS administration. After the application of C60FAS, a slower effort decrease, followed by the prolonged retention of a certain level, was recorded. An analysis of the metabolic process changes accompanying muscle fatigue showed an increase in the oxidative stress markers H 2 O 2 (hydrogen peroxide) and TBARS (thiobarbituric acid reactive substances) in relation to the intact muscles. After C60FAS administration, the TBARS content and H 2 O 2 level were decreased. The endogenous antioxidant system demonstrated a similar effect because the GSH (reduced glutathione) in the muscles and the CAT (catalase) enzyme activity were increased during fatigue. CONCLUSIONS: C60FAS leads to reduction in the recovery time of the muscle contraction force and to increase in the time of active muscle functioning before appearance of steady fatigue effects. Therefore, it is possible that C60FAS affects the prooxidant-antioxidant muscle tissue homeostasis, subsequently increasing muscle endurance.

Complex of C60 Fullerene with Doxorubicin as a Promising Agent in Antitumor Therapy.

The main aim of this work was to evaluate the effect of doxorubicin in complex with C60 fullerene (C60 + Dox) on the growth and metastasis of Lewis lung carcinoma in mice and to perform a primary screening of the potential mechanisms of C60 + Dox complex action. We found that volume of tumor from mice treated with the C60 + Dox complex was 1.4 times less than that in control untreated animals. The number of metastatic foci in lungs of animals treated with C60 + Dox complex was two times less than that in control untreated animals. Western blot analysis of tumor lysates revealed a significant decrease in the level of heat-shock protein 70 in animals treated with C60 + Dox complex. Moreover, the treatment of tumor-bearing mice was accompanied by the increase of cytotoxic activity of immune cells. Thus, the potential mechanisms of antitumor effect of C60 + Dox complex include both its direct action on tumor cells by inducing cell death and increasing of stress sensitivity and an immunomodulating effect. The obtained results provide a scientific basis for further application of C60 + Dox nanocomplexes as treatment agents in cancer chemotherapy.

C60 fullerene as synergistic agent in tumor-inhibitory Doxorubicin treatment.

BACKGROUND: Doxorubicin (Dox) is one of the most potent anticancer drugs, but its successful use is hampered by high toxicity caused mainly by generation of reactive oxygen species. One approach to protect against Dox-dependent chemical insult is combined use of the cytostatic drug with antioxidants. C60 fullerene has a nanostructure with both antioxidant and antitumor potential and may be useful in modulating cell responses to Dox. OBJECTIVE: The aim of this study was to estimate the antitumor effect and antioxidant enzyme activity of combined C60 fullerene and Dox (C60 + Dox) in the liver and heart of mice with Lewis lung carcinoma compared with Dox treatment alone. METHODS: Highly stable pristine C60 fullerene aqueous colloid solution (concentration 1.0 mg/ml, average hydrodynamic diameter of nanoparticles 50 nm) was used in the study and characterized by means of atomic force microscopy (AFM). The in vivo investigation of C60-Dox action was performed via the standard methods of histological and enzyme activity analyses. RESULTS: Dox (total dose 2.5 mg/kg) combined with C60 fullerene (total dose 25 mg/kg) in tumor-bearing animals resulted in tumor growth inhibition, prolongation of life, metastasis inhibition, and increased number of apoptotic tumor cells and was more effective than the corresponding course of Dox treatment alone. C60 fullerene demonstrated a protective effect against superoxide dismutase and glutathione peroxidase inhibition induced by Dox-dependent oxidative insult in the liver and heart. CONCLUSION: Combined treatment with C60 + Dox is considered to be a promising approach for cancer chemotherapy.

Therapeutic reactive oxygen generation.

An increase of the intracellular reactive oxygen species (ROS) concentration leads to the development of oxidative stress and, thus, to the damage of cell components. The cause-and-effect relations between these processes have not been fully established yet. The ability of photo excited supramolecular composites containing fullerenes C60 immobilized at nanosilica particles to generate reactive oxygen species (ROS) in cells of two types (rat thymocytes, and transformed cells of ascite Erlich carcinoma, EAC, and leucosis L1210) is demonstrated. The damaging effect of photo excited C60-composites are shown, which appeared to be selective and manifested in transformed cells, but not in thymocytes. It has been shown that after the irradiation of aqueous solutions or cell suspensions in the presence of fullerene C60, the generation of reactive oxygen species is observed. It has been shown that the influence of photo excited fullerene C60 on metabolic processes depends on the composition of C60-containing complex and on the type of the cells. The damaging effects of photo excited fullerene C60-containing composites were demonstrated to be selective. The data presented suggest that the application of fullerene C60-containing composites for the selective activation of ROS-dependent death program in certain types of tumor cells is very promising.

Monte Carlo simulation of intercalated carbon nanotubes.

Monte Carlo simulations of the single- and double-walled carbon nanotubes (CNT) intercalated with different metals have been carried out. The interrelation between the length of a CNT, the number and type of metal atoms has also been established. This research is aimed at studying intercalated systems based on CNTs and d-metals such as Fe and Co. Factors influencing the stability of these composites have been determined theoretically by the Monte Carlo method with the Tersoff potential. The modeling of CNTs intercalated with metals by the Monte Carlo method has proved that there is a correlation between the length of a CNT and the number of endo-atoms of specific type. Thus, in the case of a metallic CNT (9,0) with length 17 bands (3.60 nm), in contrast to Co atoms, Fe atoms are extruded out of the CNT if the number of atoms in the CNT is not less than eight. Thus, this paper shows that a CNT of a certain size can be intercalated with no more than eight Fe atoms. The systems investigated are stabilized by coordination of 3d-atoms close to the CNT wall with a radius-vector of (0.18-0.20) nm. Another characteristic feature is that, within the temperature range of (400-700) K, small systems exhibit ground-state stabilization which is not characteristic of the higher ones. The behavior of Fe and Co endo-atoms between the walls of a double-walled carbon nanotube (DW CNT) is explained by a dominating van der Waals interaction between the Co atoms themselves, which is not true for the Fe atoms.

Catalytic system of the reactive oxygen species on the C60 fullerene basis.

AIM: To study the ability of fullerenes C(60) to catalyse the reactions of generation of reactive oxygen species (ROS) in water solution after photoexcitation and to affect the vitality of tumor cells in vitro. METHODS: The number and vitality of cultured Ehrlich carcinoma cells or rat thymocytes were determined using tripane blue, ROS levels were registered using the methods of electron paramagnetic resonance (EPR) spectroscopy and spin traps, photoirradiation of water solution of fullerenes C(60) with visible light was carried out using mercury lamp. RESULTS: Irradiation of water solution of fullerenes C(60) (10(-5) M) was accompanied with generation of ROS with the rate of 10 nMol/ml/min. After addition of irradiated C(60) solution to suspension of thymocytes or ascite cells, the decrease of the number of vital cells by 67 and 58%, respectively, has been registered. CONCLUSION: Photoirradiated water solutions of fullerenes C(60) may be potentially useful for photodynamic therapy of tumors as ROS catalytic system.