Toxicity and bioactivity of cobalt nanoparticles on the monocytes

Food grade titanium dioxide (E171) interferes with monocyte-macrophage cell differentiation and their phagocytic capacity

Food grade titanium dioxide E171 has been used in products such as confectionery, doughs and flours to enhance organoleptic properties. The European Union has warned about adverse effects on humans due to oral consumption. After oral exposure, E171 reaches the bloodstream which raises the concern about effects on blood cells such as monocytes. One of the main functions of these cells is the differentiation of macrophages leading to the phagocytosis of foreign particles. The aim of this study was to evaluate the effect of E171 exposure on the phagocytic capacity and differentiation process of monocytes (THP-1) into macrophages. Physicochemical E171 properties were evaluated, and THP-1 monocytes were exposed to 4, 40 and 200 μg/ml. Cell viability, uptake capacity, cytokine release, the differentiation process, cytoskeletal arrangement and E171 internalization were assayed. Results showed that E171 particles had an amorphous shape with a mean of hydrodynamic size of ∼46 nm in cell culture media. Cell viability decreased until the 9th day of exposure, while the uptake capacity decreased up to 62% in a concentration dependent manner in monocytes. Additionally, the E171 exposure increased the proinflammatory cytokines release and decreased the cell differentiation by a 61% in macrophages. E171 induced changes in cytoskeletal arrangement and some of the E171 particles were located inside the nuclei. We conclude that E171 exposure in THP-1 monocytes induced an inflammatory response, impaired the phagocytic capacity, and interfered with cell differentiation from monocytes to macrophages.

Assessment of the Impact of Trace Essential Metals on Cancer Development

This study examines the impact of zinc, copper, cobalt, iron, and manganese on cancer development, considering their dual roles as potential promoters or inhibitors within tumorigenesis. A comprehensive analysis of existing literature and experimental data is conducted to elucidate the intricate relationship between these trace elements and cancer progression. The findings highlight the multifaceted effects of zinc, copper, cobalt, iron, and manganese on various aspects of cancer development, including cell proliferation, angiogenesis, and metastasis. Understanding the nuanced interactions between these trace elements and cancer could offer crucial insights into tumorigenesis mechanisms and facilitate the identification of novel biomarkers and therapeutic targets for cancer prevention and treatment strategies. This research underscores the importance of considering the roles of essential trace elements in cancer biology and may ultimately contribute to advancements in precision medicine approaches for combating cancer.

The Role of Trace Elements and Minerals in Osteoporosis: A Review of Epidemiological and Laboratory Findings

The objective of the present study was to review recent epidemiological and clinical data on the association between selected minerals and trace elements and osteoporosis, as well as to discuss the molecular mechanisms underlying these associations. We have performed a search in the PubMed-Medline and Google Scholar databases using the MeSH terms "osteoporosis", "osteogenesis", "osteoblast", "osteoclast", and "osteocyte" in association with the names of particular trace elements and minerals through 21 March 2023. The data demonstrate that physiological and nutritional levels of trace elements and minerals promote osteogenic differentiation through the up-regulation of BMP-2 and Wnt/β-catenin signaling, as well as other pathways. miRNA and epigenetic effects were also involved in the regulation of the osteogenic effects of trace minerals. The antiresorptive effect of trace elements and minerals was associated with the inhibition of osteoclastogenesis. At the same time, the effect of trace elements and minerals on bone health appeared to be dose-dependent with low doses promoting an osteogenic effect, whereas high doses exerted opposite effects which promoted bone resorption and impaired bone formation. Concomitant with the results of the laboratory studies, several clinical trials and epidemiological studies demonstrated that supplementation with Zn, Mg, F, and Sr may improve bone quality, thus inducing antiosteoporotic effects.

Biological Use of Nanostructured Silica-Based Materials Functionalized with Metallodrugs: The Spanish Perspective

Since the pioneering work of Vallet-Regí's group on the design and synthesis of mesoporous silica-based materials with therapeutic applications, during the last 15 years, the potential use of mesoporous silica nanostructured materials as drug delivery vehicles has been extensively explored. The versatility of these materials allows the design of a wide variety of platforms that can incorporate numerous agents of interest (fluorophores, proteins, drugs, etc.) in a single scaffold. However, the use of these systems loaded with metallodrugs as cytotoxic agents against different diseases and with distinct therapeutic targets has been studied to a much lesser extent. This review will focus on the work carried out in this field, highlighting both the pioneering and recent contributions of Spanish groups that have synthesized a wide variety of systems based on titanium, tin, ruthenium, copper and silver complexes supported onto nanostructured silica. In addition, this article will also discuss the importance of the structural features of the systems for evaluating and modulating their therapeutic properties. Finally, the most interesting results obtained in the study of the potential therapeutic application of these metallodrug-functionalized silica-based materials against cancer and bacteria will be described, paying special attention to preclinical trials in vivo.

Hematobiochemical, Oxidative Stress, and Histopathological Mediated Toxicity Induced by Nickel Ferrite (NiFe2O4) Nanoparticles in Rabbits

From the past few decades, attention towards the biological evaluation of nanoparticles (NPs) has increased due to the persistent and extensive application of NPs in various fields, including biomedical science, modern industry, magnetic resonance imaging, and the construction of sensors. Therefore, in the current study, magnetic nickel ferrite (NiFe2O4) nanoparticles (NFNPs) were synthesized and evaluated for their possible adverse effects in rabbits. The crystallinity of the synthesized NFNPs was confirmed using X-ray diffraction (XRD) technique. The saturation magnetization (46.7 emug-1) was measured using vibrating sample magnetometer (VSM) and 0.35-tesla magnetron by magnetic resonance imaging (MRI). The adverse effects of NFNPs on blood biochemistry and histoarchitecture of the liver, kidneys, spleen, brain, and heart of the rabbits were determined. A total of sixteen adult rabbits, healthy and free from any apparent infection, were blindly placed in two groups. The rabbits in group A served as control, while the rabbits in group B received a single dose (via ear vein) of NFNPs for ten days. The blood and visceral tissues were collected from each rabbit at days 5 and 10 of posttreatment. The results on blood and serum biochemistry profile indicated significant variation in hematological and serum biomarkers in NFNP-treated rabbits. The results showed an increased quantity of oxidative stress and depletion of antioxidant enzymes in treated rabbits. Various serum biochemical tests exhibited significantly higher concentrations of different liver function tests, kidney function tests, and cardiac biomarkers. Histopathologically, the liver showed congestion, edema, atrophy, and degeneration of hepatocytes. The kidneys exhibited hemorrhages, atrophy of renal tubule, degeneration, and necrosis of renal tubules, whereas coagulative necrosis, neutrophilic infiltration, and severe myocarditis were seen in different sections of the heart. The brain of the treated rabbits revealed necrosis of neurons, neuron atrophy, and microgliosis. In conclusion, the current study results indicated that the highest concentration of NPs induced adverse effects on multiple tissues of the rabbits.

Research progress on the carcinogenicity of metal nanomaterials

With the rapid development of nanotechnology, new nanomaterials with enormous potentials continue to emerge, especially metal nanomaterials. Metal nanomaterials possess the characteristics of metals and nanomaterials, so they are widely used in many fields. But at the same time, whether the use or release of metal nan4omaterials into the environment is toxic to human beings and animals has now attained widespread attention at home and abroad. Currently, it is an indisputable fact that cancer ranks among the top causes of death among residents worldwide. The properties of causing DNA damage and mutations possessed by these metal nanomaterials make them unpredictable influences in the body, subsequently leading to genotoxicity and carcinogenicity. Due to the increasing evidence of their roles in carcinogenicity, this article reviews the toxicological and carcinogenic effects of metal nanomaterials, including nano-metal elements (nickel nanoparticles, silver nanoparticles, and cobalt nanoparticles) and nano-metal oxides (titanium dioxide nanoparticles, silica nanoparticles, zinc oxide nanoparticles, and alumina nanoparticles). This article provides a reference for the researchers and policymakers to use metal nanomaterials rationally in modern industries and biomedicine.

The Importance of Evaluating the Lot-to-Lot Batch Consistency of Commercial Multi-Walled Carbon Nanotube Products

The biological response of multi-walled carbon nanotubes (MWNTs) is related to their physicochemical properties and a thorough MWNT characterization should accompany an assessment of their biological activity, including their potential toxicity. Beyond characterizing the physicochemical properties of MWNTs from different sources or manufacturers, it is also important to characterize different production lots of the same MWNT product from the same vendor (i.e., lot-to-lot batch consistency). Herein, we present a comprehensive physicochemical characterization of two lots of commercial pristine MWNTs (pMWNTs) and carboxylated MWNTs (cMWNTs) used to study the response of mammalian macrophages to MWNTs. There were many similarities between the physicochemical properties of the two lots of cMWNTs and neither significantly diminished the 24-h proliferation of RAW 264.7 macrophages up to the highest concentration tested (200 μg cMWNTs/mL). Conversely, several physicochemical properties of the two lots of pMWNTs were different; notably, the newer lot of pMWNTs displayed less oxidative stability, a higher defect density, and a smaller amount of surface oxygen species relative to the original lot. Furthermore, a 72-h half maximal inhibitory concentration (IC-50) of ~90 µg pMWNTs/mL was determined for RAW 264.7 cells with the new lot of pMWNTs. These results demonstrate that subtle physicochemical differences can lead to significantly dissimilar cellular responses, and that production-lot consistency must be considered when assessing the toxicity of MWNTs.

Local Cellular Responses to Metallic and Ceramic Nanoparticles from Orthopedic Joint Arthroplasty Implants

Over the last decades, joint arthroplasty has become a successful treatment for joint disease. Nowadays, with a growing demand and increasingly younger and active patients accepting these approaches, orthopedic surgeons are seeking implants with improved mechanical behavior and longer life span. However, aseptic loosening as a result of wear debris from implants is considered to be the main cause of long-term implant failure. Previous studies have neatly illustrated the role of micrometric wear particles in the pathological mechanisms underlying aseptic loosening. Recent osteoimmunologic insights into aseptic loosening highlight the important and heretofore underrepresented contribution of nanometric orthopedic wear particles. The present review updates the characteristics of metallic and ceramic nanoparticles generated after prosthesis implantation and summarizes the current understanding of their hazardous effects on peri-prosthetic cells.

In vitro effects of cobalt nanoparticles on aspartate aminotransferase and alanine aminotransferase activities of wistar rats

Cobalt nanoparticles (Co-NPs) have been extensively used in clinical practices and medical diagnosis. In this study, the potential toxicity effects of Co-NPs with special emphasis over the biochemical enzyme activities, such as aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) in serum, liver, and kidney of Wistar rats were investigated. This toxicity measurement of nanomaterials can support the toxicological data. The biochemical enzymatic variations are powerful tools for the assessment of toxicity. ASAT and ALAT enzymes have been widely used to predict tissue-specific toxicities associated with xenobiotic. The biochemical changes induced by Co-NPs have significance in their toxicological studies because the alterations in biochemical parameters before clinical symptoms indicate either their toxicant safety or detrimental effect. Herein, Co-NPs with particle size <50 nm significantly activated ASAT and ALAT enzymes in the serum, liver, and kidney of rats at concentration-dependent order.

Airborne environmental fine particles induce intense inflammatory response regardless of the absence of heavy metal elements

Airborne environmental particles (EP) more commonly referred as particulate matter (PM) are an illustrative marker of air pollution that is associated with adverse effects on human health. Considering, PM is a complex mixture, not only in terms of its chemical composition, but also in the range of particle size, it is difficult to identify which attribute contributes more for the toxicity. Currently, there is no report about the immunotoxicological effects caused by PM with reduced content of heavy metals. This study intends to address this gap and provides a detailed characterization and immunotoxicity evaluation of PM collected in an urban area with heavy traffic congestion. Environmental particles were separated by different sizes though a sucrose gradient. This method allowed to achieve 4 sized fractions: EP f 15 % with a mean diameter of 284 nm ± 1.86 nm, EP f 25 % with a mean diameter of 461 nm ± 1.72 nm, EP f 35 % with a mean diameter of 1845 nm ± 251 nm and EP f 45 % with a mean diameter of 2204 nm ± 310 nm. Only the fractions with the smallest sizes (EP f 15 % and EP f 25 %) were subsequently studied. The chemical composition of both fractions was not substantially different, and the dominant elements were C, O, Ca and K. Only EP f 25 % showed to have a small amount of Fe. Therefore, the heavy metal elements were eliminated through centrifugation. Essentially, we found that the EP f 15 % was more cytotoxic in RAW 264.7 cells than EP f 25 %, which indicates the smaller size as the motive for the higher toxicity. In addition, both fractions of EP presented a good internalization in macrophages after 2 h exposure and induced the production of reactive oxygen species in a concentration-dependent manner. Moreover, EP f 15 % and EP f 25 % led to a strong secretion of proinflammatory cytokines (TNF-α and IL-6) in human peripheral blood mononuclear cells (hPBMCs) in the 3 concentrations tested. The inflammatory response observed was independent of the presence of heavy metals and endotoxins, since these last were suppressed by using polymyxin B sulfate. This report emphasizes the importance of an adequate physicochemical characterization and adequate controls in the experiments to achieve a right interpretation of the biological effects caused by PM.

Diamond-like carbon films over reconstructive TMJ prosthetic materials: Effects in the cytotoxicity, chemical and mechanical properties

Increasingly more young patients have been submitted to reconstruction of the Temporomandibular Joint (TMJ), so, the prostheses must to present more functional longevity.

Objective

To evaluate the effect of diamond-like carbon film (DLC) over titanium alloy (Ti6Al4V) and polyethylene (UHWPE) samples, their mechanical and chemical properties and cellular cytotoxicity.

Methods

Titanium and UHWPE specimens, with 2.5 cm in diameter and 2 mm thickness were coated through plasma enhanced chemical vapor deposition (PECVD) with DLC or DLC doped with silver (DLC-Ag). Scanning electron microscopy (SEM) morphological analysis, Energy-dispersive spectroscopy (EDS) chemical analysis, scratching test, mechanical fatigue test, surface roughness analysis, and cellular cytotoxicity were performed. Data were statistically analyzed using one-way ANOVA (p < 0.05) or two-way ANOVA and multiple comparison Tukey test.

Results

In the SEM analysis, morphological differences were observed on substrates after DLC deposition. The film chemically modified the substrate surfaces, according to the EDS analysis. The initial critical load failure occurred at 6.1 N for DLC and 9.7 N for the DLC-Ag film. The DLC film deposition over the polyethylene promoted a decrease in the polymer's damaged area after mechanical fatigue cycling. The cytotoxicity analysis demonstrated less biocompatibility in experimental groups, when compared to control, however, increased biocompatibility was observed, at 10 days, in all groups.

Conclusion

The diamond-like carbon coating enhanced the chemical and mechanical properties from substrates, however modified biological interaction course of the titanium alloy (Ti6Al4V) and polyethylene (UHWPE) samples. Parameters for film deposition remain to be improved in order to obtain best biocompatibility.

Impact of gold nanoparticles shape on their cytotoxicity against human osteoblast and osteosarcoma in in vitro model. Evaluation of the safety of use and anti-cancer potential

Due to development of nanotechnology and gold nanoparticles (AuNPs) increasing use in different areas of medicine, especially in oncology, better understanding of their potential cytotoxicity is necessary to protect patients safety. Shape and size of AuNPs is an important modulator of their cytotoxicity. Therefore, we investigated the cytotoxicity of AuNPs rods (≈39 nm length, 18 nm width), AuNPs stars (≈ 215 nm) and AuNPs spheres (≈ 6.3 nm) against human fetal osteoblast (hFOB 1.19), osteosarcoma (143B, MG63) and pancreatic duct cell (hTERT-HPNE) lines by MTT and neutral-red uptake assay. Moreover, influence of AuNPs on level of proapoptotic protein (Bax) and anti-apoptotic protein (Bcl-2) was measured by western blot. Cellular uptake of nanoparticles and ultrastructure changes were examined by transmission electron microscopy (TEM). In the present study we have proven that AuNPs stars are the most cytotoxic against human cells. We observed that cancer cells are more susceptible to AuNPs cytotoxic effect. Furthermore, AuNPs rods and AuNPs stars caused increased expression of Bax and decreased expression of Bcl-2 protein in osteosarcoma cells. We found that AuNPs penetrated through the cell membrane and caused ultrastructural changes. Our results clearly demonstrated that the cytotoxicity of AuNPs was shape-dependent. AuNPs stars with the highest anti-cancer potential were also the most cytotoxic type of tested NPs, whereas AuNPs spheres which appears to be the safest one had small anti-cancer potential.

Low doses of Co nanoparticles induce death and regulate osteogenic differentiation in MG‑63 cells

The aim of the present study was to investigate the effects of cobalt nanoparticles (CoNPs) on the proliferation and differentiation of human osteoblasts in vitro, and to investigate the molecular mechanisms via which CoNPs affect proliferation and differentiation of osteoblasts. The MG‑63 human osteoblast cell line was treated with different concentrations of CoNPs for 12 to 48 h in vitro. At each time point, cell morphology was observed and an MTT assay was performed to assess cell viability. Alkaline phosphatase (ALP), osteocalcin (BGLAP), collagen I (COL I), osteoprotegerin (OPG) and receptor activator of nuclear factor κ‑B ligand mRNA expression levels, and ALP, BGLAP and COL protein expression levels, were assessed by reverse transcription‑quantitative polymerase chain reaction and western blotting, respectively. The viability of MG‑63 cells decreased significantly after treatment with CoNPs. As CoNP concentration increased, a higher growth inhibition and cell death was observed. Compared with CoNPs, treatment with the same concentration of Co2+ may have a greater inhibitory effect on the growth of MG‑63 cells. CoNPs affected the mRNAs expression levels of ALP, BGLAP, COL I and OPG in MG‑63 cells, and reduced the protein expression levels of ALP, BGLAP and COL I. In conclusion, the present study demonstrated that CoNPs induce cytotoxic effects on MG‑63 cells by markedly reducing cell viability and inducing cell death at high concentrations. In addition, CoNPs may inhibit the function and differentiation of osteoblasts by affecting the mRNA and protein expression levels of associated genes. The results of the present study indicate that CoNPs may serve an important role in the aseptic loosening mechanism following total joint replacement surgery, particularly in situations where metal on metal prostheses are used. Further study into inhibiting this effect is required.

Astaxanthin mitigates cobalt cytotoxicity in the MG-63 cells by modulating the oxidative stress

Background

With the re-popularity of metal-on-metal (MoM) bearing in recent years, the cobalt toxicity has been a cause for concern in the total hip replacement surgery by both physicians and patients.

Methods

MG-63 cell line was cultured in vitro and incubated with cobalt (II) chloride (CoCl₂) and/or with astaxanthin (ASX) for 24 h. MTT assay was conducted to evaluate the cell viability after cobalt exposure and ASX treatment. Fluorescence-activated cell sorting (FACS) analysis was performed to examine the reactive oxygen species (ROS) level. Quantitative real-time polymerase chain reaction (PCR) was adopted to determine the mRNA levels of related targets. And western blot analysis was used to examine the protein expressions. One-way ANOVA with posttest Newman-Keuls multiple comparisons was adopted to analysis all the obtained data.

Results

In the current study, ASX exhibited significant protective effect against the Co(II)-induced cytotoxicity in MG-63 cell line. We also found that ASX protected the cells against Co-induced apoptosis by regulating the expression of Bcl-2 family proteins. Besides, heme oxygenase 1 (HO-1) could be activated by Co exposure; ASX treatment significantly inhibited HO-1 activation, suppressing the oxidative stress induced by Co exposure. Moreover, c-Jun N-terminal Kinase (JNK) phosphorylation was shown to participate in the signaling pathway of the protective effect of ASX. However, knockdown of JNK expression by siRNA transfection or JNK inhibitor SP600125 treatment did not affect the protective effect of ASX against cobalt cytotoxicity in MG-63 cells.

Conclusions

ASX mitigated cobalt cytotoxicity in the MG-63 cells by modulating the oxidative stress. And ASX could be a promising therapy against cobalt toxicity in the hip articulation surgery.

Electronic supplementary material

The online version of this article (doi:10.1186/s40360-017-0166-1) contains supplementary material, which is available to authorized users.

Rifampin suppresses osteoclastogenesis and titanium particle-induced osteolysis via modulating RANKL signaling pathways

Wear particles liberated from the surface of prostheses are considered to be main reason for osteoclast bone resorption and that extensive osteoclastogenesis leads to peri-implant osteolysis and subsequent prosthetic loosening. The aim of this study was to assess the effect of rifampin on osteoclastogenesis and titanium (Ti) particle-induced osteolysis. The Ti particle-induced osteolysis mouse calvarial model and bone marrow-derived macrophages (BMMs) were used. Rifampin, at dose of 10 or 50 mg/kg/day, was respectively given intraperitoneally for 14 days in vivo. The calvariae were removed and processed for Further histological analysis. In vitro, osteoclasts were generated from mouse BMMs with receptor activator of nuclear factor-κB ligand (RANKL) and the macrophage colony stimulating factor. Rifampin at different concentrations was added to the medium. The cell viability, tartrate-resistant acid phosphatase (TRAP) staining, TRAP activity and resorption on bone slices were analysis. Osteoclast-specific genes and RANKL-induced MAPKs signaling were tested for further study of the mechanism. Rifampin inhibited Ti-induced osteolysis and osteoclastogenesis in vivo. In vitro data indicated that rifampin suppressed osteoclast differentiation and bone resorption in a dose-dependent manner. Moreover, rifampin significantly reduced the expression of osteoclast-specific markers, including TRAP, cathepsin K, V-ATPase d2, V-ATPase a3, c-Fos, and nuclear factor of activated T cells (NFAT) c1. Further investigation revealed that rifampin inhibited osteoclast formation by specifically abrogating RANKL-induced p38 and NF-κB signaling. Rifampin had significant potential for the treatment of particle-induced peri-implant osteolysis and other diseases caused by excessive osteoclast formation and function.

Nanotoxicity of cobalt induced by oxidant generation and glutathione depletion in MCF-7 cells

There are very few studies regarding the biological activity of cobalt-based nanoparticles (NPs) and, therefore, the possible mechanism behind the biological response of cobalt NPs has not been fully explored. The present study was designed to explore the potential mechanisms of the cytotoxicity of cobalt NPs in human breast cancer (MCF-7) cells. The shape and size of cobalt NPs were characterized by scanning and transmission electron microscopy (SEM and TEM). The crystallinity of NPs was determined by X-ray diffraction (XRD). The dissolution of NPs was measured in phosphate-buffered saline (PBS) and culture media by atomic absorption spectroscopy (AAS). Cytotoxicity parameters, such as [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide] (MTT), neutral red uptake (NRU), and lactate dehydrogenase (LDH) release suggested that cobalt NPs were toxic to MCF-7 cells in a dose-dependent manner (50-200μg/ml). Cobalt NPs also significantly induced reactive oxygen species (ROS) generation, lipid peroxidation (LPO), mitochondrial outer membrane potential loss (MOMP), and activity of caspase-3 enzymes in MCF-7 cells. Moreover, cobalt NPs decreased intracellular antioxidant glutathione (GSH) molecules. The exogenous supply of antioxidant N-acetyl cysteine in cobalt NP-treated cells restored the cellular GSH level and prevented cytotoxicity that was also confirmed by microscopy. Similarly, the addition of buthionine-[S, R]-sulfoximine, which interferes with GSH biosynthesis, potentiated cobalt NP-mediated toxicity. Our data suggested that low solubility cobalt NPs could exert toxicity in MCF-7 cells mainly through cobalt NP dissolution to Co²⁺.

The Roles of Acidosis in Osteoclast Biology

The adverse effect of acidosis on the skeletal system has been recognized for almost a century. Although the underlying mechanism has not been fully elucidated, it appears that acidosis acts as a general stimulator of osteoclasts derived from bone marrow precursors cells and enhances osteoclastic resorption. Prior work suggests that acidosis plays a significant role in osteoclasts formation and activation via up-regulating various genes responsible for its adhesion, migration, survival and bone matrix degradation. Understanding the role of acidosis in osteoclast biology may lead to development of novel therapeutic approaches for the treatment of diseases related to low bone mass. In this review, we aim to discuss the recent investigations into the effects of acidosis in osteoclast biology and the acid-sensing molecular mechanism.