Analysis of zinc oxide nanoparticles binding proteins in rat blood and brain homogenate

Evaluation of the Therapeutic Effect of Curcumin-Conjugated Zinc Oxide Nanoparticles on Reserpine-Induced Depression in Wistar Rats

Depression, a devastating brain illness, necessitates the exploration of novel antidepressant treatments. We evaluated the antidepressant effects of free curcumin, zinc oxide nanoparticles (ZnO NPs), and curcumin-conjugated zinc oxide nanoparticles (Zn(cur)O NPs). The nanoformulations were extensively characterized using advanced techniques. An acute toxicity study ensured the safety of Zn(cur)O NPs. Rats were assigned to one of five groups: control, reserpine-induced depression model, treatment with ZnO NPs, free curcumin, or Zn(cur)O NPs. Behavioral assessments (forced swimming test [FST] and open-field test [OFT]) and neurochemical analyses were conducted. Zn(cur)O NPs exhibited superior efficacy in ameliorating reserpine-induced behavioral and neurochemical effects compared to free curcumin and ZnO NPs. The reserpine-induced model displayed reduced motor activity, swimming time, and increased immobility time in the FST and OFT. Treatment with Zn(cur)O NPs 45 mg/kg significantly improved motor activity and reduced immobility time. Furthermore, Zn(cur)O NPs decreased malondialdehyde (MDA) levels while increasing reduced glutathione (GSH) and catalase (CAT) levels. Additionally, concentrations of serotonin (5-HT) and norepinephrine (NE) increased. In conclusion, curcumin-conjugated zinc oxide nanoparticles demonstrate potent antidepressant effects, alleviating depressive-like behavior in rats. These findings support Zn(cur)O NPs as a promising therapeutic strategy for depression management, warranting further investigation and clinical validation.

Size, Surface Properties, and Ion Release of Zinc Oxide Nanoparticles: Effects on Cytotoxicity, Dopaminergic Gene Expression, and Acetylcholinesterase Inhibition in Neuronal PC-12 Cells

The extensive applications of zinc oxide nanoparticles (ZnO NPs) have resulted in a substantial risk of human exposure. However, the knowledge of the toxicity of these NPs in the nervous system is still limited. A comparative analysis of ZnO NPs of various sizes and NPs of the same size, with and without surface coating, and the potential role of released zinc ions is yet to be thoroughly explored. As a result, we have studied the cellular toxicity of two different-sized ZnO NPs, ZnO-22 (22 nm) and ZnO-43 (43 nm), and NPs with similar size but with polyvinylpyrrolidone coating (ZnO-P, 45 nm). The findings from our study suggested a time-, size-, and surface coating-dependent cytotoxicity in PC-12 cells at a concentration ≥ 10 μg/ml. ZnO NP treatment significantly elevated reactive oxygen and reactive nitrogen species, thereby increasing oxidative stress. The exposure of ZnO-22 and ZnO-43 significantly upregulated the expression of monoamine oxidase-A and downregulated the α-synuclein gene expression associated with the dopaminergic system. The interaction of NPs enzymes in the nervous system is also hazardous. Therefore, the inhibition activity of acetylcholinesterase enzyme was also studied for its interaction with these NPs, and the results indicated a dose-dependent inhibition of enzyme activity. Particle size, coating, and cellular interactions modulate ZnO NP's cytotoxicity; smaller sizes enhance cellular uptake and reactivity, while coating reduces cytotoxicity by limiting direct cell contact and potentially mitigating oxidative stress. Furthermore, the study of released zinc ions from the NPs suggested no significant contribution to the observed cytotoxicity compared to the NPs.

Review of Zinc Oxide Nanoparticles: Toxicokinetics, Tissue Distribution for Various Exposure Routes, Toxicological Effects, Toxicity Mechanism in Mammals, and an Approach for Toxicity Reduction

Zinc oxide (ZnO) nanoparticles (NPs) are widely used as a sunscreen, antibacterial agent, dietary supplement, food additive, and semiconductor material. This review summarizes the biological fate following various exposure routes, toxicological effects, and toxicity mechanism of ZnO NPs in mammals. Furthermore, an approach to reduce the toxicity and biomedical applications of ZnO NPs are discussed. ZnO NPs are mainly absorbed as Zn2+ and partially as particles. Regardless of exposure route, elevated Zn concentration in the liver, kidney, lungs, and spleen are observed following ZnO NP exposure, and these are the target organs for ZnO NPs. The liver is the main organ responsible for ZnO NP metabolism and the NPs are mainly excreted in feces and partly in urine. ZnO NPs induce liver damage (oral, intraperitoneal, intravenous, and intratracheal exposure), kidney damage (oral, intraperitoneal, and intravenous exposure) and lung injury (airway exposure). Reactive oxygen species (ROS) generation and induction of oxidative stress may be a major toxicological mechanism for ZnO NPs. ROS are generated by both excess Zn ion release and the particulate effect resulting from the semiconductor or electronic properties of ZnO NPs. ZnO NP toxicity can be reduced by coating their surface with silica, which prevents Zn2+ release and ROS generation. Due to their superior characteristics, ZnO NPs are expected to be used for biomedical applications, such as bioimaging, drug delivery, and anticancer agents, and surface coatings and modification will expand the biomedical applications of ZnO NPs further.

Progress and Challenges in the Diagnosis and Treatment of Brain Cancer Using Nanotechnology

Primary brain cancer or brain cancer is the overgrowth of abnormal or malignant cells in the brain or its nearby tissues that form unwanted masses called brain tumors. People with malignant brain tumors suffer a lot, and the expected life span of the patients after diagnosis is often only around 14 months, even with the most vigorous therapies. The blood-brain barrier (BBB) is the main barrier in the body that restricts the entry of potential chemotherapeutic agents into the brain. The chances of treatment failure or low therapeutic effects are some significant drawbacks of conventional treatment methods. However, recent advancements in nanotechnology have generated hope in cancer treatment. Nanotechnology has shown a vital role starting from the early detection, diagnosis, and treatment of cancer. These tiny nanomaterials have great potential to deliver drugs across the BBB. Beyond just drug delivery, nanomaterials can be simulated to generate fluorescence to detect tumors. The current Review discusses in detail the challenges of brain cancer treatment and the application of nanotechnology to overcome those challenges. The success of chemotherapeutic treatment or the surgical removal of tumors requires proper imaging. Nanomaterials can provide imaging and therapeutic benefits for cancer. The application of nanomaterials in the diagnosis and treatment of brain cancer is discussed in detail by reviewing past studies.

Exposure to Zinc Oxide Nanoparticles Increases Estradiol Levels and Induces an Antioxidant Response in Antral Ovarian Follicles In Vitro

The use of zinc oxide nanoparticles (ZnO NP) in consumer products is increasing, raising concern about their potential toxicity to human health. Nanoparticles have endocrine disrupting effects and can induce oxidative stress, leading to biomolecule oxidation and cell dysfunction. The ovary is one of the most important endocrine organs in female reproduction. Nanoparticles accumulate in the ovary, but it is unknown whether and how exposure to these materials disrupts antral follicle functions. Thus, this study tested the hypothesis that the in vitro exposure to ZnO NPs affects the steroidogenic pathway and induces oxidative stress in ovarian antral follicles. Antral follicles from CD-1 mice were cultured with ZnO NPs (5, 10, and 15 µg/mL) for 96 h. ZnO NP exposure did not affect apoptosis and cell cycle regulators at any of the tested concentrations. ZnO NP exposure at low levels (5 µg/mL) increased aromatase levels, leading to increased estradiol levels and decreased estrogen receptor alpha (Esr1) expression. ZnO NP exposure at 15 µg/mL induced an antioxidant response in the antral follicles as evidenced by changes in expression of antioxidant molecules (Nrf2, Cat, Sod1, Gsr, Gpx) and decreased levels of reactive oxygen species. Interestingly, ZnO NPs dissolve up to 50% in media and are internalized in cells as soon as 1 h after culture. In conclusion, ZnO NPs are internalized in antral follicles, leading to increased estrogen production and an antioxidant response.

Neuroprotective effects of quercetin on the cerebellum of zinc oxide nanoparticles (ZnoNps)-exposed rats

Engineered nanomaterials induce hazardous effects at the cellular and molecular levels. We investigated different mechanisms underlying the neurotoxic potential of zinc oxide nanoparticles (ZnONPs) on cerebellar tissue and clarified the ameliorative role of Quercetin supplementation. Forty adult male albino rats were divided into control group (I), ZnONPs-exposed group (II), and ZnONPs and Quercetin group (III). Oxidative stress biomarkers (MDA & TOS), antioxidant biomarkers (SOD, GSH, GR, and TAC), serum interleukins (IL-1β, IL-6, IL-8), and tumor necrosis factor alpha (TNF-α) were measured. Serum micro-RNA (miRNA): miRNA-21-5p, miRNA-122-5p, miRNA-125b-5p, and miRNA-155-3p expression levels were quantified by real-time quantitative polymerase-chain reaction (RT-QPCR). Cerebellar tissue sections were stained with Hematoxylin & Eosin and Silver stains and examined microscopically. Expression levels of Calbindin D28k, GFAP, and BAX proteins in cerebellar tissue were detected by immunohistochemistry. Quercetin supplementation lowered oxidative stress biomarkers levels and ameliorated the antioxidant parameters that were decreased by ZnONPs. No significant differences in GR activity were detected between the study groups. ZnONPs significantly increased serum IL-1β, IL-6, IL-8, and TNF-α which were improved with Quercetin. Serum miRNA-21-5p, miRNA-122-5p, miRNA-125b-5p, and miRNA-155-p expression levels showed significant increase in ZnONPs group, while no significant difference was observed between Quercetin-treated group and control group. ZnONPs markedly impaired cerebellar tissue structure with decreased levels of calbindin D28k, increased BAX and GFAP expression. Quercetin supplementation ameliorated cerebellar tissue apoptosis, gliosis and improved calbindin levels. In conclusion: Quercetin supplementation ameliorated cerebellar neurotoxicity induced by ZnONPs at cellular and molecular basis by different studied mechanisms.Abbreviations: NPs: Nanoparticles, ROS: reactive oxygen species, ZnONPs: Zinc oxide nanoparticles, AgNPs: silver nanoparticles, BBB: blood-brain barrier, ncRNAs: Non-coding RNAs, miRNA: Micro RNA, DMSO: Dimethyl sulfoxide, LPO: lipid peroxidation, MDA: malondialdehyde, TBA: thiobarbituric acid, TOS: total oxidative status, ELISA: enzyme-linked immunosorbent assay, H2O2: hydrogen peroxide, SOD: superoxide dismutase, GR: glutathione reductase, TAC: total antioxidant capacity, IL-1: interleukin-1, TNF: tumor necrosis factor alpha, cDNA: complementary DNA, RT-QPCR: Real-time quantitative polymerase-chain reaction, ABC: Avidin biotin complex technique, DAB: 3', 3-diaminobenzidine, SPSS: Statistical Package for Social Sciences, ANOVA: One way analysis of variance, Tukey's HSD: Tukey's Honestly Significant Difference, GFAP: glial fiberillar acitic protein, iNOS: Inducible nitric oxide synthase, NO: nitric oxide, HO-1: heme oxygenase-1, Nrf2: nuclear factor erythroid 2-related factor 2, NF-B: nuclear factor-B, SCI: spinal cord injury, CB: Calbindin.

Nano-inspired smart medicines targeting brain cancer: diagnosis and treatment

Cancer, despite being the bull's eye for the research community, accounts for a large number of morbidity and mortality. Cancer of the brain is considered the most intractable, with the least diagnosis rates, hence treatment and survival. Despite the extensive development of therapeutic molecules, their targeting to the diseased site is a challenge. Specially tailored nanoparticles can efficiently deliver drugs and genes to the brain to treat tumours and diseases. These nanotechnology-based strategies target the blood-brain barrier, the local space, or a specific cell type. These nanoparticles are preferred over other forms of targeted drug delivery due to the chances for controlled delivery of therapeutic cargo to the intended receptor. Targeted cancer therapy involves using specific receptor-blocking compounds that block the spreading or growth of cancerous cells. This review presents an account of the recent applications of nano-based cancer theragnostic, which deal in conjunct functionalities of nanoparticles for effective diagnosis and treatment of cancer. It commences with an introduction to tumours of the brain and their grades, followed by hurdles in its conventional diagnosis and treatment. The characteristic mechanism of nanoparticles for efficiently tracing brain tumour grade and delivery of therapeutic genes or drugs has been summarised. Nanocarriers like liposomes have been widely used and commercialized for human brain cancer treatment. However, nano-inspired structures await their translational recognition. The green synthesis of nanomaterials and their advantages have been discussed. The article highlights the challenges in the nano-modulation of brain cancer and its future outlook.

Protective Impact of Edaravone Against ZnO NPs-induced Oxidative Stress in the Human Neuroblastoma SH-SY5Y Cell Line

Extensive applications of ZnO NPs (zinc oxide nanoparticles) in daily life have created concern about their biotoxicity. Zinc oxide nanoparticles induce oxidative stress, inflammation, and apoptosis in neurons. Edaravone applies antioxidant agent and anti-inflammatory impacts in the different cells, as evaluated in both in vitro and in vivo experimental models. This study is designed to explore, how edaravone would avert mitochondrial impairment in human neuronal cells against ZnO NPs-induced toxicity. Accordingly, we analyzed here whether a pretreatment (for 24 h) with edaravone (10-100 μM) would enhance mitochondrial protection in the human neuroblastoma cells SH-SY5Y against ZnO NPs-induced toxicity. We found that edaravone at 25 μM averted the ZnO NPs-induced decrease in the amounts of adenosine triphosphate (ATP), just as on the activity of the complexes I and V. Also, edaravone induced an antioxidant activity by diminishing the levels of lipid peroxidation, protein carbonylation, and protein nitration in the mitochondrial membranes. Edaravone blocked the ZnO NPs-induced transcription factor nuclear factor-κB (NF-κB) upregulation. The inhibition of the heme oxygenase-1 (HO-1) enzyme by zinc protoporphyrin IX (ZnPP IX, 10 μM) smothered the preventive impacts brought about by edaravone with respect to mitochondrial function and inflammation. After this examination, it can be concluded that edaravone caused cytoprotective impacts in an HO-1-dependent manner in SH-SY5Y cells against ZnO NPs-induced toxicity.

Zinc Oxide Nanoparticles Induce Ferroptotic Neuronal Cell Death in vitro and in vivo

Purpose

Zinc oxide nanoparticles (ZnONPs) are one of the most important nanomaterials that are widely used in the food, cosmetic and medical industries. Humans are often exposed to ZnONPs via inhalation, and they may reach the brain where neurotoxic effects could occur via systemic distribution. However, the mechanisms underlying how ZnONPs produce neurotoxic effects in the brain remain unclear. In this study, we aimed to investigate the novel mechanism involved in ZnONPs-induced neurotoxicity.

Methods and Results

We demonstrated for the first time that pulmonary exposure to ZnONPs by intratracheal instillation could trigger ferroptosis, a new form of cell death, in the neuronal cells of mouse cerebral cortex. A similar phenomenon was also observed in cultured neuron-like PC-12 cell line. By using a specific inhibitor of ferroptosis ferrostatin-1 (Fer-1), our results showed that inhibition of ferroptosis by Fer-1 could significantly alleviate the ZnONPs-induced neuronal cell death both in vivo and in vitro. Mechanistic investigation revealed that ZnONPs selectively activated the JNK pathway and thus resulted in the ferroptotic phenotypes, JNK inhibitor SP600125 could reverse lipid peroxidation upregulation and ferroptotic cell death induced by ZnONPs in PC-12 cells.

Conclusion

Taken together, this study not only demonstrates that pulmonary exposure of ZnONPs can induce JNK-involved ferroptotic cell death in mouse cortex and PC-12 cells, but also provides a clue that inhibition of ferroptosis by specific agents or drugs may serve as a feasible approach for reducing the untreatable neurotoxicity induced by ZnONPs.

Feasibility Study of Mesoporous Silica Particles for Pulmonary Drug Delivery: Therapeutic Treatment with Dexamethasone in a Mouse Model of Airway Inflammation

Diseases in the respiratory tract rank among the leading causes of death in the world, and thus novel and optimized treatments are needed. The lungs offer a large surface for drug absorption, and the inhalation of aerosolized drugs are a well-established therapeutic modality for local treatment of lung conditions. Nanoparticle-based drug delivery platforms are gaining importance for use through the pulmonary route. By using porous carrier matrices, higher doses of especially poorly soluble drugs can be administered locally, reducing their side effects and improving their biodistribution. In this study, the feasibility of mesoporous silica particles (MSPs) as carriers for anti-inflammatory drugs in the treatment of airway inflammation was investigated. Two different sizes of particles on the micron and nanoscale (1 µm and 200 nm) were produced, and were loaded with dexamethasone (DEX) to a loading degree of 1:1 DEX:MSP. These particles were further surface-functionalized with a polyethylene glycol–polyethylene imine (PEG–PEI) copolymer for optimal aqueous dispersibility. The drug-loaded particles were administered as an aerosol, through inhalation to two different mice models of neutrophil-induced (by melphalan or lipopolysaccharide) airway inflammation. The mice received treatment with either DEX-loaded MSPs or, as controls, empty MSPs or DEX only; and were evaluated for treatment effects 24 h after exposure. The results show that the MEL-induced airway inflammation could be treated by the DEX-loaded MSPs to the same extent as free DEX. Interestingly, in the case of LPS-induced inflammation, even the empty MSPs significantly down-modulated the inflammatory response. This study highlights the potential of MSPs as drug carriers for the treatment of diseases in the airways.

Zinc Oxide Nanoparticles Induced Oxidative DNA Damage, Inflammation and Apoptosis in Rat's Brain after Oral Exposure

Growing evidences demonstrated that zinc oxide nanoparticles (ZnONPs) could reach the brain after oral ingestion; however, the "neurotoxicity of" ZnONPs after oral exposure has not been fully investigated. This study aimed to explore the "neurotoxicity of" ZnONPs (.

Exposure to Zinc Oxide Nanoparticles Induces Neurotoxicity and Proinflammatory Response: Amelioration by Hesperidin

Zinc oxide nanoparticles (ZnONPs) are widely used in food packaging and may enter the body directly if exposed. Hereby, in this study, the oral administration was selected as the route of exposure for rats to nanoparticles and the effect of hesperidin (HSP, 100 mg/kg bwt) was evaluated on ZnONP (600 mg/kg bwt)-induced neurotoxicity in rats. ZnONPs were characterized using transmission electron microscopy. Neurotoxicity was observed as seen by elevation in serum inflammatory markers including tumor necrosis factor alpha (TNF-α), interleukin 1 (IL-1β), interleukin-6 (IL-6), C-reactive protein (CRP), and activities of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione (GSH) content in rat brains. Pretreatment of rats with HSP in ZnONP-treated group elevated activities of antioxidant enzymes. HSP also caused decrease in TNF-α, IL-1β, IL-6, and CRP levels which was higher in the ZnONP-treated group. The results suggest that HSP augments antioxidant defense with anti-inflammatory response against ZnONP-induced neurotoxicity. The increased antioxidant enzymes enhance the antioxidant potential to reduce oxidative stress.

Surface modification of zinc oxide nanoparticles with amorphous silica alters their fate in the circulation

Nanoparticle (NP) pharmacokinetics and biological effects are influenced by many factors, especially surface physicochemical properties. We assessed the effects of an amorphous silica coating on the fate of zinc after intravenous (IV) injection of neutron activated uncoated (65)ZnO or silica-coated (65)ZnO NPs in male Wistar Han rats. Groups of IV-injected rats were sequentially euthanized, and 18 tissues were collected and analyzed for (65)Zn radioactivity. The protein coronas on each ZnO NP after incubation in rat plasma were analyzed by SDS-PAGE gel electrophoresis and mass spectrometry of selected gel bands. Plasma clearance for both NPs was biphasic with rapid initial and slower terminal clearance rates. Half-lives of plasma clearance of silica-coated (65)ZnO were shorter (initial - <1 min; terminal - 2.5 min) than uncoated (65)ZnO (initial - 1.9 min; terminal - 38 min). Interestingly, the silica-coated (65)ZnO group had higher (65)Zn associated with red blood cells and higher initial uptake in the liver. The (65)Zn concentrations in all the other tissues were significantly lower in the silica-coated than uncoated groups. We also found that the protein corona formed on silica-coated ZnO NPs had higher amounts of plasma proteins, particularly albumin, transferrin, A1 inhibitor 3, α-2-hs-glycoprotein, apoprotein E and α-1 antitrypsin. Surface modification with amorphous silica alters the protein corona, agglomerate size, and zeta potential of ZnO NPs, which in turn influences ZnO biokinetic behavior in the circulation. This emphasizes the critical role of the protein corona in the biokinetics, toxicology and nanomedical applications of NPs.

Neurotoxicity induced by zinc oxide nanoparticles: age-related differences and interaction

This study mainly investigated the neurotoxicity induced by zinc oxide nanoparticle (ZnO NP) in different-aged mice and the interaction between age and ZnO NP exposure. Sixty adult and old male C57BL/6J mice were assigned to four groups based on a two-factor (age and ZnO NP exposure) design. Results showed that ZnO NPs (5.6 mg/kg, intraperitoneal) induced increased production of pro-inflammatory cytokines in the serum and the brain of mice. A synergistic reaction between aging and ZnO NP exposure occurred regarding serum interleukin 1 (IL-1) and interleukin 6 (IL-6). In the brain, increased oxidative stress level, impaired learning and memory abilities, and hippocampal pathological changes were identified, especially in old mice, following ZnO NP exposure. Then, a potential mechanism of cognitive impairment was examined. The contents of hippocampal cAMP response element binding protein (CREB), phosphorylated CREB, synapsin I, and cAMP were decreased in an age-dependent manner, and the most substantial decrease occurred in old mice treated with ZnO NPs. These findings demonstrated for the first time that aging and ZnO NP exposure synergistically influenced systemic inflammation, and indicated old individuals were more susceptible to ZnO NP-induced neurotoxicity. One of the mechanisms might due to the supression of cAMP/CREB signaling.

Role of surface modification in zinc oxide nanoparticles and its toxicity assessment toward human dermal fibroblast cells

The wide-scale applications of zinc oxide (ZnO) nanoparticles (NPs) in photocatalysts, gas sensors, and cosmetics may cause toxicity to humans and environments. Therefore, the aim of the present study was to reduce the toxicity of ZnO NPs by coating them with a silica (SiO2) layer, which could be used in human applications, such as cosmetic preparations. The sol-gel method was used to synthesize core ZnO with SiO2-shelled NPs (SiO2/ZnO NPs) with varying degrees of coating. Diverse studies were performed to analyze the toxicity of NPs against cells in a dose- and time-dependent manner. To ensure the decreased toxicity of the produced SiO2/ZnO NPs, cytotoxicity in membrane damage and/or intracellular reactive oxygen species (ROS) were assessed by employing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, lactate dehydrogenase, 2',7'-dichlorofluorescin, and lipid peroxide estimations. The cores of ZnO NPs exhibited cytotoxicity over time, regardless of shell thickness. Nevertheless, the thicker SiO2/ZnO NPs revealed reduced enzyme leakage, decreased peroxide production, and less oxidative stress than their bare ZnO NPs or thinner SiO2/ZnO NPs. Therefore, thicker SiO2/ZnO NPs moderated the toxicity of ZnO NPs by restricting free radical formation and the release of zinc ions, and decreasing surface contact with cells.