A facile approach to hydrophilic oxidized fullerenes and their derivatives as cytotoxic agents and supports for nanobiocatalytic systems.

A facile, environment-friendly, versatile and reproducible approach to the successful oxidation of fullerenes (oxC60) and the formation of highly hydrophilic fullerene derivatives is introduced. This synthesis relies on the widely known Staudenmaier's method for the oxidation of graphite, to produce both epoxy and hydroxy groups on the surface of fullerenes (C60) and thereby improve the solubility of the fullerene in polar solvents (e.g. water). The presence of epoxy groups allows for further functionalization via nucleophilic substitution reactions to generate new fullerene derivatives, which can potentially lead to a wealth of applications in the areas of medicine, biology, and composite materials. In order to justify the potential of oxidized C60 derivatives for bio-applications, we investigated their cytotoxicity in vitro as well as their utilization as support in biocatalysis applications, taking the immobilization of laccase for the decolorization of synthetic industrial dyes as a trial case.

Antitumor effects of the electromagnetic resonant frequencies derived from the 1H NMR spectrum of Ph3Sn(Mercaptonicotinic)SnPh3 complex.

The aim of this article is to investigate the potential cytotoxic and antitumor effects of the resonant electromagnetic fields (rEMFs) derived from the 1H NMR spectrum of the Ph3Sn(Mercaptonicotinic)SnPh3 complex (SnMNA). The ability of the complex's rEMFs to induce leiomyosarcoma (LMS) cell death and to recess tumor (leiomyosarcoma) development in Wistar rats was evaluated. The effects of the simultaneous administration of the SnMNA complex at extremely low concentrations and exposure to its rEMFs was also investigated. The emission of the 1H NMR spectrum of the complex alone or in a combination with low ineffective doses of the complex decreased LMS cell viability mainly through apoptosis. Moreover, the results from the in vivo experiments showed a significant prolongation of life expectancy in tumor-bearing rats exposed to the rEMFs alongside a deceleration in tumor growth rate. We speculate that the rEMFs of a biologically active substance could exert similar biological effects as the substance itself, mainly when is combined with extremely low ineffective concentrations of the substance.

Vanillylmandelic acid protects against reperfusion injury in an experimental animal model of myocardial infarction.

Vanillylmandelic acid, a catecholamine end-metabolite, has been shown to have several biological properties in previous studies, despite considered biologically inactive. We examined the potential effects of vanillylmandelic acid on the ischemic heart following myocardial infarction and reperfusion on a rat model. Thirty-four female Wistar rats were randomized into two groups, control and experimental. They were anesthetized and subjected to myocardial infarction through left anterior descending artery ligation. A previously studied dose of vanillylmandelic acid (10 mg/kg) was administered and the following parameters were studied during ischemia and reperfusion: a) mortality b) severity of ventricular tachyarrhythmias c) premature ventricular contractions and d) heart rate. Administration of vanillymandelic acid significantly reduced the severity of ventricular tachyarrhythmias and mortality rate during reperfusion, while it did not affect any other of the parameters studied. In conclusion, reperfusion injury was blunted through vanillylmandelic acid administration, which seems to be mediated by parasympathetic activation.

Modulation of cisplatin cytotoxic activity against leiomyosarcoma cells by epigallocatechin-3-gallate.

The aim of this study was to investigate the cytotoxic effect cisplatin in combination with epigallocatechin-3-gallate (EGCG) on leiomyosarcoma cells (LMS cells) in order to identify a less toxic but equally effective alternative. Assays for cell proliferation, colony formation efficiency, induction of apoptosis and cell cycle arrest were performed using the IC50 of cisplatin (8.6 µΜ) as a reference value and a concentration of EGCG (30 µΜ) that caused a non-significant reduction in cell proliferation. Pre-treatment of cells with EGCG for 24 h before the addition of cisplatin increased cytotoxicity up to 8.5% (p < 0.05) and the number of apoptotic cells by 40%. Epigallocatechin-3-gallate failed to alter S-phase cell cycle arrest induced by cisplatin and to modulate cisplatin effects on mitochondrial function. These results indicate that pre-treatment with EGCG could be used as an adjunctive therapy to maximise effectiveness of chemotherapy.

The healing effect of four different silver complexes on full-thickness skin burns in a rat model.

AIM: This study was carried-out to investigate the effect of four different silver substances (S1, S2, S3, and S4) on burn wound healing in a rat model. MATERIALS AND METHODS: One hundred and eighty Wistar rats were used. Animals were randomized into six groups to receive no treatment (CG, control group), and local application of the solvent of silver substances (SG, solvent group), as well as of the four silver substances (EG1-EG4 groups for substances S1-S4, respectively). On days 0, 3, 6, 12, 21, and 31 following burn wound infliction, the size and healing progress of each wound were recorded and evaluated by means of clinical evaluation, planimetry and histological examination. RESULTS: According to our findings lower infection rates, as well as significantly accelerated wound healing and faster re-epithelialization were recorded in EG1, EG2, and EG4 compared to the other groups. DISCUSSION: The use of S1, S2, and S4 substances proved to be an effective treatment of burn wounds that ensured better outcomes compared to the control and solvent groups, as well as with the use of S3 substance. Nevertheless, they failed to produce short-term healing of the full-thickness burn. Further research is required to examine the possibility of speeding the treatment of full-thickness burns by these complexes in order to reduce healing time to acceptable limits and prevent the need for surgery.

Cardiovascular and pulmonary adaptations during short-term 15° and 30° head-down posture in healthy male volunteers.

INTRODUCTION: Healthy male volunteers were investigated for cardiopulmonary adaptations to a head-down posture (HDT). METHODS: Thirty-three volunteers were enrolled in this study. Their changes in cardiopulmonary parameters at 15° and 30° HDT, for 7.5 minutes in each posture, were studied using echocardiography. Spirometric measurements of pulmonary function were performed during sitting and supine positions, and 15° and 30° HDT, while measurements of blood pressure, carotid blood flow, and electrocardiographic (ECG) and echocardiographic examinations were performed in the supine position and under 15° and 30° HDT. RESULTS: A significant increase (p<0.05) in mean, systolic, and diastolic pressure, and a decrease in heart rate (p<0.05) were observed during the HDT postures. Right ventricular diameter increased (p<0.05) from supine to 15° and 30° HDT. Forced vital capacity, forced expiratory volume in 1 s, and peak flow rate decreased significantly from supine to 15° and 30° HDT. Maximum ventilatory volume decreased significantly only from the sitting to the supine posture and then remained steady in the HDT postures. CONCLUSIONS: During short-term HDT, the cardiovascular system maintains a stable ejection fraction, with a significant in heart rate, and a decrease in pulmonary ventilation.

Cardiovascular effects of vanillylmandelic acid in rats.

The main catecholamine end-metabolites have been considered biologically inactive, but accumulated evidence indicates a variety of pharmacological actions after exogenous administration. We examined the dose-related haemodynamic effects of vanillylmandelic acid in the in vivo rat-model. One hundred and sixteen Wistar rats (250 ± 20 g) were studied under continuous electrocardiographic monitoring; invasive blood pressure was recorded for 60 min through a catheter in the right common carotid artery. Measurements were performed at baseline and after vanillylmandelic acid (1, 10, 100mg/kg) and homovanillic acid (10mg/kg) intra-arterial administration. To examine the underlying mechanisms, the haemodynamic effects were compared with those (a) after trimetazidine administration, which has similar structure due to a tri-methylated phenolic ring; (b) after epinephrine and isoprenaline administration following vanillylmandelic acid pretreatment; (c) after vanillylmandelic acid administration post-bilateral vagotomy. Vanillylmandelic acid, homovanillic acid and (to a lesser extent) trimetazidine decreased heart rate and mean arterial blood pressure. This effect was blunted in vagotomized animals. Comparable effects were noted in heart rate and blood pressure after adrenaline and isoprenaline infusion, with and without vanillylmandelic acid-pretreatment. In conclusion, vanillylmandelic acid administration decreases heart rate dose-dependently, mediated by increased vagal tone, without α- or ß-adrenergic-receptor blocking effects. The pharmacological properties of compounds with a mono- and tri-methylated phenolic ring merit further investigation.

Oxidative stress in patients treated with continuous ambulatory peritoneal dialysis (CAPD) and the significant role of vitamin C and E supplementation.

PURPOSE: Chronic renal failure patients undergoing peritoneal dialysis (PD) are characterized by increased oxidative stress (OS), which is associated with enhanced cardiovascular risk. Moreover, oxidative stress also contributes to peritoneal membrane changes and ultrafiltration failure. The aim of this study was to evaluate OS in PD patients and the effect of treatment with ascorbic acid and α-tocopherol. METHODS: Plasma, erythrocyte, urine, and peritoneal effluent samples from 20 patients on PD were evaluated for glutathione peroxidase and superoxide dismutase activity, total antioxidant capacity (TAC) and malondialdehyde (MDA) levels, as well as protein carbonyl formation, before and after administration of vitamin C, alone or in combination with vitamin E, in comparison with 10 apparently healthy control individuals. RESULTS: All studied markers showed enhanced OS in the PD group, compared to controls. The supplementation of vitamin C and E resulted in improvements of all the OS markers, as indicated by increased erythrocyte antioxidant enzymes activity and TAC levels, as well as decreased MDA concentration and carbonyl compound formation. CONCLUSIONS: The oral supplementation of antioxidant vitamins C and E, in combination, can lead to decreased OS, thus providing a useful and cost-effective therapeutic option in PD patients.

Effects of catechin and epicatechin on superoxide dismutase and glutathione peroxidase activity, in vivo.

OBJECTIVES: The objective of this study was to investigate the effects of catechin and epicatechin on the activity of the endogenous antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) (as well as the total antioxidant capacity (TAC)) of rats after intra-peritoneal (i.p.) administration. METHODS: Twenty-four Wistar rats were randomly divided into two groups: the experimental group which was administered daily with a 1:1 mixture of epicatechin and catechin at a concentration of 23 mg/kg body weight for 10 days and the control group which was injected daily with an equal amount of saline. Blood and urine samples were collected before and after the administration period, as well as 10 days after (follow-up). RESULTS: Intra-peritoneal administration of catechins led to a potent decrease in GPx levels and a significant increase in SOD levels. TAC was significantly increased in plasma and urine. Malonaldehyde levels in urine remained stable. In the animals treated with catechins, SOD activity showed a moderate negative correlation with GPx activity. DISCUSSION: Boosting the activity of the antioxidant enzymes could be a potential adjuvant approach for the treatment of the oxidative stress-related diseases.

Analgesic effect of the electromagnetic resonant frequencies derived from the NMR spectrum of morphine.

Exposure to various types of electromagnetic fields (EMFs) affects pain specificity (nociception) and pain inhibition (analgesia). Previous study of ours has shown that exposure to the resonant spectra derived from biologically active substances' NMR may induce to live targets the same effects as the substances themselves. The purpose of this study is to investigate the potential analgesic effect of the resonant EMFs derived from the NMR spectrum of morphine. Twenty five Wistar rats were divided into five groups: control group; intraperitoneal administration of morphine 10 mg/kg body wt; exposure of rats to resonant EMFs of morphine; exposure of rats to randomly selected non resonant EMFs; and intraperitoneal administration of naloxone and simultaneous exposure of rats to the resonant EMFs of morphine. Tail Flick and Hot Plate tests were performed for estimation of the latency time. Results showed that rats exposed to NMR spectrum of morphine induced a significant increase in latency time at time points (p < 0.05), while exposure to the non resonant random EMFs exerted no effects. Additionally, naloxone administration inhibited the analgesic effects of the NMR spectrum of morphine. Our results indicate that exposure of rats to the resonant EMFs derived from the NMR spectrum of morphine may exert on animals similar analgesic effects to morphine itself.

Effects of pulsed electromagnetic fields on benign prostate hyperplasia.

INTRODUCTION: Benign prostate hyperplasia (BPH) has been treated with various types of electromagnetic radiation methods such as transurethral needle ablation (TUNA), interstitial laser therapy (ILC), holmium laser resection (HoLRP). In the present study, the effects of a noninvasive method based on the exposure of patients with BPH to a pulsative EM Field at radiofrequencies have been investigated. MATERIALS AND METHODS: Twenty patients with BPH, aging 68-78 years old (y.o), were enrolled in the study. Patients were randomly divided into two groups: the treatment group (10 patients, 74.0 ± 5.7 y.o) treated with the α-blocker Alfusosin, 10 mg/24 h for at least 4 weeks, and the electromagnetic group (10 patients, 73.7 ± 6.3 y.o) exposed for 2 weeks in a very short wave duration, pulsed electromagnetic field at radiofrequencies generated by an ion magnetic inductor, for 30 min daily, 5 consecutive days per week. Patients of both groups were evaluated before and after drug and EMF treatment by values of total PSA and prostatic PSA fraction, acid phosphate, U/S estimation of prostate volume and urine residue, urodynamic estimation of urine flow rate, and International Prostate Symptom Score (IPSS). RESULTS: There was a statistically significant decrease before and after treatment of IPSS (P < 0.02), U/S prostate volume (P < 0.05), and urine residue (P < 0.05), as well as of mean urine flow rate (P < 0.05) in patients of the electromagnetic group, in contrast to the treatment group who had only improved IPSS (P < 0.05). There was also a significant improvement in clinical symptoms in patients of the electromagnetic group. Follow-up of the patients of this group for one year revealed that results obtained by EMFs treatment are still remaining. CONCLUSION: Pulsed electromagnetic field at radiofrequencies may benefit patients with benign prostate hyperplasia treated by a non-invasive method.

Inhibition of platelet aggregation and immunomodulation of NK lymphocytes by administration of ascorbic acid.

Platelets aggregation around migrating tumor cells offers protection against the cytotoxic activity of the natural killers cells (NKC). The ascorbic acid in 3 x 10(-3) M concentration completely inhibited platelet aggregation, decreased thromboxane B2 levels, and inhibited the expression of platelet membranic receptor GpIIb/IIIa in non stimulated platelets, and increased the NKC cytotoxicity in an average rate of 105, 61, and 285% in the NKC/targets cells ratios 12.5:1, 25:1 and 50:1 respectively. The results suggest the role of ascorbic acid in increasing the susceptibility of tumor cells to NKC; the ascorbic acid could be used as part of a multidrug therapy to treat diseases which up to now have been treated only through chemotherapy.

Vitamin C transiently arrests cancer cell cycle progression in S phase and G2/M boundary by modulating the kinetics of activation and the subcellular localization of Cdc25C phosphatase.

Regulation of cell cycle progression involves redox (oxidation-reduction)-dependent modification of proteins including the mitosis-inducing phosphatase Cdc25C. The role of vitamin C (ascorbic acid, ASC), a known modulator of the cellular redox status, in regulating mitotic entry was investigated in this study. We demonstrated that vitamin C inhibits DNA synthesis in HeLa cells and, mainly the form of dehydroascorbic acid (DHA), delays the entry of p53-deficient synchronized HeLa and T98G cancer cells into mitosis. High concentrations of Vitamin C caused transient S and G2 arrest in both cell lines by delaying the activation of the M-phase promoting factor (MPF), Cdc2/cyclin-B complex. Although vitamin C did not inhibit the accumulation of cyclin-B1, it may have increased the level of Cdc2 inhibitory phosphorylation. This was achieved by transiently maintaining Cdc25C, the activator of Cdc2, both in low levels and in a phosphorylated on Ser216 inactive form that binds to 14-3-3 proteins contributing thus to the nuclear exclusion of Cdc25C. As expected, vitamin C prevented the nuclear accumulation of Cdc25C in both cell lines. In conclusion, it seems that vitamin C induces transient cell cycle arrest, at least in part, by delaying the accumulation and the activation of Cdc25C.

Solid state and solution studies of a vanadium(III)-L-cysteine compound and demonstration of its antimetastatic, antioxidant and inhibition of neutral endopeptidase activities.

Reaction of one equivalent of vanadium(III) chloride with three equivalents of l-cysteine(H2Cys) in methyl alcohol affords a VIII-Cys compound that is formulated as [VIII(Hcys)3].2HCl.2.5H2O 1. The solid state characterization of 1 was performed by microanalysis, circular dichroism (CD) and infrared studies as well as room temperature magnetic susceptibility. These studies have shown coordination of each HCys- ligand to the VIII atom through an amine nitrogen and a carboxylate oxygen atoms. Solution studies of 1 were carried out in water and methanol by UV-visible, CD and electron paramagnetic resonance (EPR) spectroscopies. According to these studies, it was evident that despite the progressive oxidation of 1 to oxovanadium(IV) species, some V(III) species were also present in solution after several hours. Compound 1, VIVOSO4.5H2O and l-cysteine were examined for their total antioxidant capacity (TAC) and lag time. Compound 1 exhibited significantly greater total antioxidant capacity and lag time values than l-cysteine. VIVOSO4.5H2O did not show any total antioxidant capacity or lag time. The inhibition of neutral endopeptidase (NEP) activity caused by 1, VIVOSO4.5H2O and thiorphan was also measured. Compound 1, at a concentration of 10(-3) M, showed inhibition of NEP activity as potent as thiorphan at 10(-6) M, while VIVOSO4.5H2O in the same concentration exhibited less than 50% inhibitory activity than that of thiorphan at 10(-6) M. Moreover, the antimetastatic effects of compound 1, l-cysteine and VIVOSO4.5H2O were examined on Wistar rats, treated with 3,4-benzopyrene. The results revealed that 1 prevents significantly lung metastases (only 9.5% of animals treated with 1 showed metastases), whereas 47-52% of the rats of the control group and those treated with l-cysteine and VIVOSO4.5H2O exhibited metastases.

Vanadium in cancer treatment.

Vanadium compounds exert preventive effects against chemical carcinogenesis on animals, by modifying, mainly, various xenobiotic enzymes, inhibiting, thus, carcinogen-derived active metabolites. Studies on various cell lines reveal that vanadium exerts its antitumor effects through inhibition of cellular tyrosine phosphatases and/or activation of tyrosine phosphorylases. Both effects activate signal transduction pathways leading either to apoptosis and/or to activation of tumor suppressor genes. Furthermore, vanadium compounds may induce cell-cycle arrest and/or cytotoxic effects through DNA cleavage and fragmentation and plasma membrane lipoperoxidation. Reactive oxygen species generated by Fenton-like reactions and/or during the intracellular reduction of V(V) to V(IV) by, mainly, NADPH, participate to the majority of the vanadium-induced intracellular events. Vanadium may also exert inhibitory effects on cancer cell metastatic potential through modulation of cellular adhesive molecules, and reverse antineoplastic drug resistance. It also possesses low toxicity that, in combination with the synthesis of new, more potent and better tolerated complexes, may establish vanadium as an effective non-platinum, metal antitumor agent.