Novel nanoformulation of disulfiram with bacterially synthesized copper oxide nanoparticles for augmenting anticancer activity: an in vitro study

Background Disulfiram (DS), in the presence of copper (Cu), exhibited potent broad anticancer activity. However, its clinical application is limited due to the poor solubility and stability. Hence, a novel nanocombination of DS with bacterially synthesized copper oxide nanoparticles (CuO NPs) was prepared herein to improve the anticancer efficacy of the typical DS–Cu complex. Our design utilized the nanocharacterization and prooxidant effect-mediated anticancer activity of CuO NPs which may lead to enhanced cellular uptake and thus improved anticancer efficacy of this unique nanocomplex. Results The characterized DS–CuO NPs exhibited high stability in serum and the strongest selective anticancer activity, with the lowest half-maximum inhibitory concentration (IC50 < 15 nM), against human breast, lung and liver cancer cells, by >10-fold, compared to DS–Cu, CuO NPs and Cu. Importantly, DS–CuO NPs revealed better synergistic anticancer effect and higher cellular uptake than DS–Cu. Moreover, this novel nanocomplex showed higher prooxidant effect-mediated apoptosis and anti-metastatic potential. This was accomplished by elevating cellular reactive species content with inhibiting the antioxidant defenders (functional marker of cancer stem cells (aldehyde dehydrogenase) and nuclear factor erythroid 2-related factor2), matrix metallopeptidase 9 and NF-κB as well as enhancing p53 expression. Conclusion All of the aforementioned findings verified that this novel nanocomplex was capable of improving the therapeutic index of the conventional DS–Cu complex. The potent selective anticancer activity of this promising nanomedicine merits further investigation, as a separate future study, using animal models as preliminary step before its clinical application. Graphic abstract

Mitochondrial fatty acid utilization increases chromatin oxidative stress in cardiomyocytes

The inability of adult mammalian cardiomyocytes to proliferate underpins the development of heart failure following myocardial injury. Although the newborn mammalian heart can spontaneously regenerate for a short period of time after birth, this ability is lost within the first week after birth in mice, partly due to increased mitochondrial reactive oxygen species (ROS) production which results in oxidative DNA damage and activation of DNA damage response. This increase in ROS levels coincides with a postnatal switch from anaerobic glycolysis to fatty acid (FA) oxidation by cardiac mitochondria. However, to date, a direct link between mitochondrial substrate utilization and oxidative DNA damage is lacking. Here, we generated ROS-sensitive fluorescent sensors targeted to different subnuclear compartments (chromatin, heterochromatin, telomeres, and nuclear lamin) in neonatal rat ventricular cardiomyocytes, which allowed us to determine the spatial localization of ROS in cardiomyocyte nuclei upon manipulation of mitochondrial respiration. Our results demonstrate that FA utilization by the mitochondria induces a significant increase in ROS detection at the chromatin level compared to other nuclear compartments. These results indicate that mitochondrial metabolic perturbations directly alter the nuclear redox status and that the chromatin appears to be particularly sensitive to the prooxidant effect of FA utilization by the mitochondria.

Synthetic Hexanucleotides as a Tool to Overcome Excessive Neutrophil Activation Caused by CpG-Containing Oligonucleotides

Mimicking bacterial DNA, synthetic CpG-containing oligodeoxyribonucleotides (CpG-ODNs) have a powerful immunomodulatory potential. Their practical application is mainly associated with the production of vaccines, where they are used as adjuvants, as well as in local antimicrobial therapy. CpG-ODNs act on a wide variety of immune cells, including neutrophilic granulocytes. On the one hand, the stimulatory effect provides both the direct implementation of their antimicrobial and fungicidal mechanisms, and an avalanche-like strengthening of the immune signal due to interaction with other participants in the immune process. On the other hand, hyperactivation of neutrophilic granulocytes can have negative consequences. In particular, the formation of unreasonably high amounts of reactive oxygen species leads to tissue damages and, as a consequence, a spontaneous aggravation and prolongation of the inflammatory process. Under physiological conditions, a large number of DNA fragments are present in inflammation foci: both of microbial and self-tissue origin. We investigated effects of several short modified hexanucleotides on the main indicators of neutrophil activation, as well as their influence on the immunomodulatory activity of known synthetic CpG-ODNs. The results obtained show that short oligonucleotides partially inhibit the prooxidant effect of synthetic CpG-ODNs without significantly affecting the ability of the latter to overcome bacteria-induced pro-survival effects on neutrophilic granulocytes.

Concentration Dependence of the Antioxidant and Prooxidant Activity of Trolox in HeLa Cells: Involvement in the Induction of Apoptotic Volume Decrease

Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), a hydrophilic analog of vitamin E, is known for its strong antioxidant activity, being a high radical scavenger of peroxyl and alkoxyl radicals. Under particular conditions, Trolox may also exhibit prooxidant properties. The present work aimed at studying the dual antioxidant/prooxidant behavior of Trolox over a wide range of concentrations (from 2.5 to 160 µM) in HeLa cells. In particular, the study addressed the dose-dependent effects of Trolox on the oxidative cell status and vitality of HeLa cells, focusing on the potential role of the vitamin E analog in the induction of one of the first steps of the apoptotic process, Apoptotic Volume Decrease (AVD). In HeLa cells, Trolox showed significant antioxidant activity, expressed as the ability to reduce the endogenous ROS production detected by the ROS-sensitive probe 5-(and-6)-chloromethyl-2′,7′-dichlorodihydrofluorescein diacetate (CM-H2DCFDA), at low concentrations (range: 2.5–15 µM), but exerted a dose-dependent prooxidant effect at higher concentrations after 24 h exposure. The prooxidant effect was paralleled by the reduction in cell viability due to the induction of the apoptotic process. The dual behavior, antioxidant at lower concentrations and prooxidant at higher concentrations, was evident also earlier after 2 h incubation, and it was paralleled by the isotonic shrinkage of the cells, ascribed to AVD. The use of SITS, known Cl− channel blocker, was able to completely inhibit the Trolox-induced isotonic cell shrinkage, demonstrating the involvement of the vitamin E analog in the alteration of cell volume homeostasis and, in turn, in the AVD induction. In conclusion, the study shed light on the concentration dependence of the Trolox antioxidant/prooxidant activity in HeLa cells and revealed its role in the induction of one of the first events of apoptosis, AVD, at high concentrations.

Prooxidant effect of α-tocopherol in pancreatic tumors.

e16698 Background: The coexistence of neuroendocrine tumors and pancreatic adenocarcinoma is rare, and treatment of such mixed tumors is challenging due to the differences in their natural course and response to systemic therapy. There is growing evidence that vitamins affect the biology of pancreatic tumors. The purpose of the study was to measure concentrations of retinol (RET), α-tocopherol (α-TCP) and diene conjugates (DC) in the blood of patients with pancreatic cancer in order to reveal its pathogenetic characteristics. Methods: Blood levels of RET and α-TCP (ELISA methods, Cloud-Clone Corp, USA), their ratio and DC concentrations (biochemical method) were measured before treatment if 42 patients with pancreatic cancer: adenocarcinoma (AC), T1-3N0-1M0, n = 9; AC with a neuroendocrine component (AC+NE) (up to 30%), n = 21; neuroendocrine tumors (NET), T1-3N0-1M0, n = 12. 22 healthy men of similar age were controls. All patients gave their voluntary informed consent for the study. Results: RET levels in all patient were statistically significantly lower than in controls: in AC by 3.8 times, in AC+NE by 1.9 times, in NET by 3.7 times (p = 0.0000). Concentrations of α-TCP in AC were 1.6 times (p = 0.0011) lower than in controls, in AC+NE were similar, and in NET α-TCP was 1.5 times higher than in controls (p = 0.0000). The ratio of α-TCP/RET in all patients significantly exceeded control values: in AC by 2.2 times, in AC+NE by 1.6 times, in NET by 5.7 times (p = 0.0000). Levels of DC in all patients were higher than in controls: in AC by 2.5, in AC+NE by 2.1, in NET by 2.7 times (p = 0.0001). Conclusions: Changes in serum levels of RET and α-TCP differ in patients with AC, NET and mixed tumors, which causes changes in the balance of vitamins and can contribute to a prooxidant effect, as evidenced by an increase in DC levels.

Indoxyl Sulfate, a Uremic Endotheliotoxin

Chronic kidney disease (CKD) is associated with a high prevalence of cardiovascular diseases. During CKD, the uremic toxin indoxyl sulfate (IS)—derived from tryptophan metabolism—accumulates. IS is involved in the pathophysiology of cardiovascular complications. IS can be described as an endotheliotoxin: IS induces endothelial dysfunction implicated in cardiovascular morbidity and mortality during CKD. In this review, we describe clinical and experimental evidence for IS endothelial toxicity and focus on the various molecular pathways implicated. In patients with CKD, plasma concentrations of IS correlate with cardiovascular events and mortality, with vascular calcification and atherosclerotic markers. Moreover, IS induces a prothrombotic state and impaired neovascularization. IS reduction by AST-120 reverse these abnormalities. In vitro, IS induces endothelial aryl hydrocarbon receptor (AhR) activation and proinflammatory transcription factors as NF-κB or AP-1. IS has a prooxidant effect with reduction of nitric oxide (NO) bioavailability. Finally, IS alters endothelial cell and endothelial progenitor cell migration, regeneration and control vascular smooth muscle cells proliferation. Reducing IS endothelial toxicity appears to be necessary to improve cardiovascular health in CKD patients.

Mitochondrial Dysfunctions May Be One of the Major Causative Factors Underlying Detrimental Effects of Benzalkonium Chloride

Benzalkonium chloride (BAC) is currently the most commonly used antimicrobial preservative in ophthalmic solutions, nasal sprays, and cosmetics. However, a large number of clinical and experimental investigations showed that the topical administration of BAC-containing eye drops could cause a variety of ocular surface changes, from ocular discomfort to potential risk for future glaucoma surgery. BAC-containing albuterol may increase the risk of albuterol-related systemic adverse effects. BAC, commonly present in personal care products, in cosmetic products can induce irritation and dose-dependent changes in the cell morphology. The cationic nature of BAC (it is a quaternary ammonium) suggests that one of the major targets of BAC in the cell may be mitochondria, the only intracellular compartment charged negatively. However, the influence of BAC on mitochondria has not been clearly understood. Here, the effects of BAC on energy parameters of rat liver mitochondria as well as on yeast cells were examined. BAC, being a “weaker” uncoupler, potently inhibited respiration in state 3, diminished the mitochondrial membrane potential, caused opening of the Ca2+/Pi-dependent pore, blocked ATP synthesis, and promoted H2O2 production by mitochondria. BAC triggered oxidative stress and mitochondrial fragmentation in yeast cells. BAC-induced oxidative stress in mitochondria and yeast cells was almost totally prevented by the mitochondria-targeted antioxidant SkQ1; the protective effect of SkQ1 on mitochondrial fragmentation was only partial. Collectively, these data showed that BAC acts adversely on cell bioenergetics (especially on ATP synthesis) and mitochondrial dynamics and that its prooxidant effect can be partially prevented by the mitochondria-targeted antioxidant SkQ1.

ACUTE TOXICITY OF CERIUM DIOXIDE NANOPARTICLES

The resorptive effects of 0.01 M cerium nanodioxide sol upon single intraperitoneal administration to rats have been studied. The acute exposure to nanoparticles was found to have a dose-dependent general toxic effect on the body (weight loss, inflammatory changes in the abdominal organs, modification of individual behavior, hematological changes, metabolic imbalance), which develops on the background of POL activation. The prooxidant effect of cerium dioxide nanoparticles is demonstratively manifested at relatively high exposure levels (80–8 mg / kg). The threshold dose for the general toxic effect (Limch integr) is equal to 0.8 mg / kg.

Is a Meal without Wine Good for Health?

Hippocrates, the father of medicine, had said: “Wine is a thing wonderfully appropriate to man if, in health as in disease, it is administered with appropriate and just measure according to the individual constitution.” Wine has always accompanied humanity, for religion or for health. Christians and Jews need wine for the liturgy. For Plato, wine was an indispensable element in society and the most important in the symposium. In this second part of the banquet, mixed with water, the wine gave the word. If the French paradox made a lot of ink flow; it was the wine that was originally responsible for it. Many researchers have tried to study alcohol and polyphenols in wine, in order to solve the mystery. Beyond its cardiovascular effects, there are also effects on longevity, metabolism, cancer prevention, and neuroprotection, and the list goes on. The purpose of this work is to make an analysis of the current knowledge on the subject. Indeed, if the paradigm of antioxidants is seductive, it is perhaps by their prooxidant effect that the polyphenols act, by an epigenetic process mediated by nrf2. Wine is a preserve of antioxidants for the winter and it is by this property that the wine acts, in an alcoholic solution. A wine without alcohol is pure heresy. Wine is the elixir that by design, over millennials, has acted as a pharmacopeia that enabled man to heal and prosper on the planet. From Alvise Cornaro to Serge Renaud, nutrition was the key to health and longevity, whether the Cretan or Okinawa diet, it is the small dose of alcohol (wine or sake) that allows the bioavailability of polyphenols. Moderate drinking gives a protection for diseases and a longevity potential. In conclusion, let us drink fewer, but drink better, to live older.

Is a Meal without Wine Good for the Health?

Hippocrate, the father of medicine, already said:"Wine is a thing wonderfully appropriate to man if, in health as in disease, it is administered with appropriate and just measure according to the individual constitution." wine has always accompanied humanity, for religion or for health. Christians and Jews need wine for the liturgy. For Platon the wine was an indispensable element in society and took all its importance in the symposium. In this second part of the banquet, mixed with water, the wine gave the word. If the french paradox made a lot of ink flow; it was the wine that was originally responsible for it. Many researchers have tried to share the alcohol and polyphenols in order to solve the mystery. Beyond its cardiovascular effects, there are also effects on longevity, metabolism, cancer prevention and neuroprotection, and the list goes on. The purpose of this work is to make an analysis of current knowledge on the subject. Indeed, if the paradigm of the antioxidants is seductive, it is perhaps by their prooxidant effect that the polyphenols could act, by an epigenetic process mediated by nrf2. Wine is a preserve of antioxidants for the winter and it is by this property that the wine acts, in alcoholic solution. A wine without alcohol is pure heresy. By the way, we were not talking about elixir to design all this millennial pharmacopee that made the man was able to heal and prosper on the planet. From Alvise Cornaro to Serge Renaud, nutrition was the key to health and longevity, whether Cretan or Okinawa diet, it is the small dose of alcohol (wine or sake) that allows the bioavailability of polyphenols. Moderate drinking give a protection for diseases and a longevity potential. In conclusion, let&rsquo;s drink fewer, but drink better to live older.