Doxorubicin-Conjugated Zinc Oxide Nanoparticles, Biogenically Synthesised Using a Fungus Aspergillus niger, Exhibit High Therapeutic Efficacy against Lung Cancer Cells

Synthesis of Zinc Oxide-Doped Carbon Dots for Treatment of Triple-Negative Breast Cancer

Introduction

The anti-cancer properties of zinc oxide-doped carbon dots (CDs/ZnO) in inhibiting triple-negative breast cancer (TNBC) progression merit more investigation.

Methods

With citric acid as the carbon source, urea applied as the nitrogen source, and zinc oxide (ZnO) used as a reactive dopant, CDs/ZnO were synthesized by microwave heating in the current study, followed by the characterization and biocompatibility assessments. Subsequently, the anti-cancer capabilities of CDs/ZnO against TNBC progression were evaluated by various biochemical and molecular techniques, including viability, proliferation, migration, invasion, adhesion, clonogenicity, cell cycle distribution, apoptosis, redox homeostasis, metabolome, and transcriptome assays of MDA-MB-231 cells. Additionally, the in vivo anti-cancer potentials of CDs/ZnO against TNBC progression were analyzed using TNBC xenograft mouse models.

Results

The biocompatibility of CDs/ZnO was supported by the non-significant changes in the pathological and physiological parameters in the CDs/ZnO treated mice, alongside a non-cytotoxic effect of CDs/ZnO on the proliferation of normal cells. Notably, the CDs/ZnO treatments effectively decreased the viability, proliferation, migration, invasion, adhesion, and clonogenicity of MDA-MB-231 cells. Furthermore, the CDs/ZnO treatments induced cell cycle arrest, apoptosis, redox imbalance, metabolome disturbances, and transcriptomic alterations of MDA-MB-231 cells by regulating the MAPK signaling pathway. Additionally, the CDs/ZnO treatments markedly suppressed the in vivo tumor growth in the TNBC xenograft mouse models.

Conclusion

In this study, we synthesized CDs/ZnO via microwave heating, using citric acid as the carbon source, urea as the nitrogen source, and ZnO as a reactive dopant. We confirmed the biosafety and potent anti-cancer efficacy of CDs/ZnO in inhibiting TNBC progression by disrupting malignant cell behaviors through modulation of the MAPK signaling pathway.

Biogenically synthesized gold nanocarrier ameliorated antiproliferative and apoptotic efficacy of doxorubicin against lung cancer

Introduction

Conventional chemotherapy treatment is commonly linked to significant side effects due to high therapeutic doses. In this regard, nanoformulations with chemotherapeutic medications hold promise in enhancing drug effectiveness through the reduction of therapeutic dosages, thereby mitigating the potential for adverse side effects. Because of numerous applications in the biomedical arena, there has been a rising interest in developing an environmentally acceptable, long-lasting, and affordable technique for the production of gold nanoparticles. In this particular context, the incorporation of plant extracts in the production of metallic nanoparticles has garnered the interest of numerous scholars. Here, we report the synthesis of gold particles by the green method using Cannabis sativa L. leaf extract and their conjugation with doxorubicin.

Methods

The gold nanoparticles were synthesized by using Cannabis sativa extract and were characterized with various biophysical techniques. Subsequently, gold nanoparticles were conjugated with doxorubicin and their efficacy was tested on A549 cells.

Results and Discussion

The biogenic synthesis of gold nanoparticles was ascertained through an absorption peak at a wavelength of 524 nm, and it was shifted to 527 nm when conjugated with doxorubicin. Nanoparticles were found to be stable exhibiting a zeta potential value of -20.1 mV, and it changed to -12.7 mV when loaded with doxorubicin. The hydrodynamic diameter of nanoparticles was determined to be 45.64 nm and it was increased to 58.95 nm when conjugated with the drug. The average size of nanoparticles analyzed by TEM was found to be approximately 17.2 nm, while it was 23.5 nm in the case of drug-nanoconjugate. Moreover, there was a significant amelioration in the antiproliferative potential of doxorubicin against lung cancer A549 cells when delivered with gold nanocarrier, which was evident by the lower IC50 and IC75 values of drug-nanoconjugates in comparison to drug alone. Furthermore, the inhibitory effect of drug-nanoconjugates and drug alone was characterized by alteration in the cell morphology, nuclear condensation, increased production of reactive oxygen species, abrogation of mitochondrial membrane potential, and enhanced caspase activities in A549 cells. In sum, our results suggested enhanced efficacy of doxorubicin-gold nanoconjugates, indicating effective delivery of doxorubicin inside the cell by gold nanoparticles.

Excellent antibacterial and anti-inflammatory efficacy of amoxicillin by AgNPs and their conjugates synthesized using Micromeria biflora crude flavonoid extracts

Antibacterial resistance is considered to be one of the major causes for mortality in coming years. In recent years green nanotechnology played a key role in addressing this problem. Biocompatible metal nanoparticles have gained popularity owing to their excellent therapeutic effects and minimal side effects.

Method

We report the synthesis of AgNPs and their amoxicillin conjugates (Ag-amoxi) using Micromeria biflora crude flavonoid extracts. The physicochemical properties of the synthesized NPs and Ag-amoxi conjugates were systematically evaluated using scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR), and UV-visible (UV-Vis) spectroscopic techniques.

Results

The average sizes of AgNPs and Ag-amoxi conjugates were 45 and 62 nm, respectively. We have also explored the antibacterial, antioxidant, anti-inflammatory, and analgesic properties of the AgNPs and Ag-amoxi conjugates through in vivo and in vitro analysis. The Ag-amoxi conjugates showed better antibacterial potential against Streptococcus Pneumoniae (S.P), Staphylococcus aureus (S.A), Pseudomonas aeruginosa (P.A), and Methicillin resistance Staphylococcus aureus (MRSA) strain both the drug and AgNPs. Similarly, in vivo anti-inflammatory studies revealed that both Ag-amoxi (68 %) and AgNPs (64 %) had strong anti-inflammatory effects, with (***p < 0.001) significance at a dose of 10 mg kg-1 body weight as compared to standard, amoxicillin (45 %), and flavonoids extract (48 %) at a dose of 100 mg kg-1. The findings of the antinociceptive activities (writhing and hot plate tests) demonstrated that the Ag-amoxi conjugates produced fewer writhing (15 in 20 s) and a shorter latency time of 22 s as compared to vehicle-treated (tramadol) animals, amoxicillin, and P.E at much lower doses. In vitro antioxidant studies revealed that the Ag-amoxi conjugate has the potential to be used as an antioxidant with an IC50 value of 43.58, compared with AgNPs (46.34), amoxicillin (58.17), compared to the standard of ascorbic acid (34.14).

Conclusion

These results reveals that these biologically inspired AgNPs and Ag-amoxi conjugate could be used to improve antibiotic efficiency and could play a critical role in addressing the multidrug resistance problem in coming years.

pH-Sensitive doxorubicin delivery using zinc oxide nanoparticles as a rectified theranostic platform: in vitro anti-proliferative, apoptotic, cell cycle arrest and in vivo radio-distribution studies

Despite enormous advancements in its management, cancer is the world's primary cause of mortality. Therefore, tremendous strides were made to produce intelligent theranostics with mitigated side effects and improved specificity and efficiency. Thus, we developed a pH-sensitive theranostic platform composed of dextran immobilized zinc oxide nanoparticles, loaded with doxorubicin and radiolabeled with the technetium-99m radionuclide (99mTc-labelled DOX-loaded ZnO@dextran). The platform measured 11.5 nm in diameter with -12 mV zeta potential, 88% DOX loading efficiency and 98.5% radiolabeling efficiency. It showed DOX release in a pH-responsive manner, releasing 93.1% cumulatively at pH 5 but just 7% at pH 7.4. It showed improved intracellular uptake, which resulted in a high growth suppressive effect against MCF-7 cancer cells as compared to the free DOX. It boasted a 4 times lower IC50 than DOX, indicating its significant anti-proliferative potential (0.14 and 0.55 μg ml-1, respectively). The in vitro biological evaluation revealed that its molecular mode of anti-proliferative action included downregulating Cdk-2, which provoked G1/S cell cycle arrest, and upregulating both the intracellular ROS level and caspase-3, which induced apoptosis and necrosis. The in vivo experiments in Ehrlich-ascites carcinoma bearing mice demonstrated that DOX-loaded ZnO@dextran showed a considerable 4-fold increase in anti-tumor efficacy compared to DOX. Moreover, by utilizing the diagnostic radionuclide (99mTc), the radiolabeled platform (99mTc-labelled DOX-loaded ZnO@dextran) was in vivo monitored in tumor-bearing mice, revealing high tumor accumulation (14% ID g-1 at 1 h p.i.) and reduced uptake in non-target organs with a 17.5 T/NT ratio at 1 h p.i. Hence, 99mTc-labelled DOX-loaded ZnO@dextran could be recommended as a rectified tumor-targeted theranostic platform.

Cytotoxicity of green synthesized zinc oxide nanoparticles using Musa acuminata on Vero cells

Zinc oxide nanoparticles (ZnO NPs) have become a highly regarded substance in various industries especially biologically synthesized ZnO NPs due to their adherence to the principles of green chemistry. However, concerns have been raised regarding the potential cytotoxic effects of ZnO NPs on biological systems. This study aimed to investigate and compare the cytotoxicity of ZnO NPs that were synthesized through chemical (C-ZnO NPs) and green approach using Musa acuminata leaf aqueous extract (Ma-ZnO NPs) on Vero cells. Characterization of ZnO NPs through Uv-Vis, FESEM, EDX, XRD, FTIR and XPS confirmed the successful synthesis of C- and Ma-ZnO NPs. MTT and ROS assays revealed that C- and Ma-ZnO NPs induced a concentration- and time-dependent cytotoxic effect on Vero cells. Remarkably, Ma-ZnO NPs showed significantly higher cell viability compared to C-ZnO NPs. The corelation of ROS and vell viability suggest that elevated ROS levels can lead to cell damage and even cell death. Flow cytometry analysis indicated that Ma-ZnO NPs exposed cells had more viable cells and a smaller cell population in the late and early apoptotic stage. Furthermore, more cells were arrested in the G1 phase upon exposure to C-ZnO NPs, which is associated with oxidative stress and DNA damage caused by ROS generation, proving its higher cytotoxicity than Ma-ZnO NPs. Similarly, time-dependent cytotoxicity and morphological alterations were observed in C- and Ma-ZnO NPs treated cells, indicating cellular damage. Furthermore, fluorescence microscopy also demonstrated a time-dependent increase in ROS formation in cells exposed to C- and Ma-ZnO NPs. In conclusion, the findings suggest that green ZnO NPs possess a favourable biocompatibility profile, exhibiting reduced cytotoxicity compared to chemically synthesized ZnO NPs on Vero cells. These results emphasize the potential of green synthesis methods for the development of safer and environmentally friendly ZnO NPs.

Zinc Oxide Nanoparticles and Cancer Chemotherapy: Helpful Tools for Enhancing Chemo-sensitivity and Reducing Side Effects?

Cancer chemotherapy is still a serious challenge. Chemo-resistance and destructive side effects of chemotherapy drugs are the most critical limitations of chemotherapy. Chemo-resistance is the leading cause of chemotherapy failure. Chemo-resistance, which refers to the resistance of cancer cells to the anticancer effects of chemotherapy drugs, is caused by various reasons. Among the most important of these reasons is the increase in the efflux of chemotherapy drugs due to the rise in the expression and activity of ABC transporters, the weakening of apoptosis, and the strengthening of stemness. In the last decade, a significant number of studies focused on the application of nanotechnology in cancer treatment. Considering the anti-cancer properties of zinc, zinc oxide nanoparticles have received much attention in recent years. Some studies have indicated that zinc oxide nanoparticles can target the critical mechanisms of cancer chemo-resistance and enhance the effectiveness of chemotherapy drugs. These studies have shown that zinc oxide nanoparticles can reduce the activity of ABC transporters, increase DNA damage and apoptosis, and attenuate stemness in cancer cells, leading to enhanced chemo-sensitivity. Some other studies have also shown that zinc oxide nanoparticles in low doses can be helpful in minimizing the harmful side effects of chemotherapy drugs. In this article, after a brief overview of the mechanisms of chemo-resistance and anticancer effects of zinc, we will review all these studies in detail.

Exploration of inorganic nanoparticles for revolutionary drug delivery applications: a critical review

The nanosystems for delivering drugs which have evolved with time, are being designed for greater drug efficiency and lesser side-effects, and are also complemented by the advancement of numerous innovative materials. In comparison to the organic nanoparticles, the inorganic nanoparticles are stable, have a wide range of physicochemical, mechanical, magnetic, and optical characteristics, and also have the capability to get modified using some ligands to enrich their attraction towards the molecules at the target site, which makes them appealing for bio-imaging and drug delivery applications. One of the strong benefits of using the inorganic nanoparticles-drug conjugate is the possibility of delivering the drugs to the affected cells locally, thus reducing the side-effects like cytotoxicity, and facilitating a higher efficacy of the therapeutic drug. This review features the direct and indirect effects of such inorganic nanoparticles like gold, silver, graphene-based, hydroxyapatite, iron oxide, ZnO, and CeO2 nanoparticles in developing effective drug carrier systems. This article has remarked the peculiarities of these nanoparticle-based systems in pulmonary, ocular, wound healing, and antibacterial drug deliveries as well as in delivering drugs across Blood-Brain-Barrier (BBB) and acting as agents for cancer theranostics. Additionally, the article sheds light on the plausible modifications that can be carried out on the inorganic nanoparticles, from a researcher's perspective, which could open a new pathway.

Methotrexate-conjugated zinc oxide nanoparticles exert a substantially improved cytotoxic effect on lung cancer cells by inducing apoptosis

In the current study, we report the synthesis of methotrexate-conjugated zinc oxide nanoparticles (MTX-ZnONPs) and their high efficacy against lung cancer cells. Conjugation of MTX with ZnONPs was authenticated by UV-vis spectroscopy, dynamic light scattering (DLS), Fourier-transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). This drug-nanoconjugate also showed high drug-loading efficiency. The therapeutic efficacy of MTX-ZnONPs was further tested in vitro against A549 cells, and the results of MTT and LDH release assays showed that MTX-ZnONPs, in addition to free MTX, were efficient in exerting cytotoxic effect on A549 cells; however, the effectiveness of MTX-ZnONPs was found to be considerably enhanced at very low doses compared to that of free MTX. Moreover, ZnONPs alone significantly inhibited the cell viability of A549 cells at a much higher concentration compared to MTX-ZnONPs and MTX. Furthermore, the cytomorphology of A549 cells was characterized by cellular shrinkage and detachment from the surface in all the treatment groups. Similarly, A549 cells, in all the treatment groups, showed fragmented and condensed nuclei, indicating the initiation of apoptosis. Mitochondrial membrane potential (ψm) in A549 cells showed a gradual loss in all the treatment groups. Results of the qualitative and quantitative analyses depicted increased reactive oxygen species (ROS) levels in A549 cells. The results of the caspase activity assay showed that MTX-ZnONPs andfree MTX caused significant activation of caspase-9, -8, and -3 in A549 cells; however, the effect of MTX-ZnONPs was more profound at very low doses compared to that of free MTX. Thus, our results showed high efficacy of MTX-ZnONPs, suggesting efficient intracellular delivery of the drug by ZnONPs as nanocarriers.

Mitochondrial-targeted nanoparticles: Delivery and therapeutic agents in cancer

Mitochondria are the powerhouses of cells and modulate the essential metabolic functions required for cellular survival. Various mitochondrial pathways, such as oxidative phosphorylation or production of reactive oxygen species (ROS) are dysregulated during cancer growth and development, rendering them attractive targets against cancer. Thus, the delivery of antitumor agents to mitochondria has emerged as a potential approach for treating cancer. Recent advances in nanotechnology have provided innovative solutions for overcoming the physical barriers posed by the structure of mitochondrial organelles, and have enabled the development of efficient mitochondrial nanoplatforms. In this review, we examine the importance of mitochondria during neoplastic development, explore the most recent smart designs of nano-based systems aimed at targeting mitochondria, and highlight key mitochondrial pathways in cancer cells.

Scaling-up strategies for controllable biosynthetic ZnO NPs using cell free-extract of endophytic Streptomyces albus: characterization, statistical optimization, and biomedical activities evaluation

In this study, we identified a suitable precursor and good cellular compartmentalization for enhancing bioactive metabolites to produce biosynthetic zinc oxide nanoparticles (ZnO NPs). An effective medium for cultivating endophytic Streptomyces albus strain E56 was selected using several optimized approaches in order to maximize the yield of biosynthetic ZnO NPs. The highest biosynthetic ZnO NPs yield (4.63 g/L) was obtained when pipetting the mixed cell-free fractions with 100 mM of zinc sulfate as a precursor. The generation of biosynthetic ZnO NPs was quickly verified using a colored solution (white color) and UV-Visible spectroscopy (maximum peak, at 320 nm). On a small scale, the Taguchi method was applied to improve the culture medium for culturing the strain E56. As a result, its cell-dry weight was 3.85 times that of the control condition. And then the biosynthesis of ZnO NPs (7.59 g/L) was increased by 1.6 times. Furthermore, by using the Plackett-Burman design to improve the utilized biogenesis pathway, the biosynthesis of ZnO NPs (18.76 g/L) was increased by 4.3 times. To find the best growth production line, we used batch and fed batch fermentation modes to gradually scale up biomass output. All kinetics of studied cell growth were evaluated during fed-batch fermentation as follows: biomass yield was 271.45 g/L, yield coefficient was 94.25 g/g, and ZnO NPs yield was 345.32 g/L. In vitro, the effects of various dosages of the controllable biosynthetic ZnO NPs as antimicrobial and anticancer agents were also investigated. The treatments with controllable biosynthetic ZnO NPs had a significant impact on all the examined multidrug-resistant human pathogens as well as cancer cells.

Rubus Capped Zinc Oxide Nanoparticles Induce Apoptosis in MCF-7 Breast Cancer Cells

Rubus fairholmianus (RF) has widely been used to treat various ailments, including pain, diabetes, and cancer. Zinc oxide nanoparticles (ZnO NPs) have drawn attention in modern healthcare applications. Hence, we designed this study to synthesize zinc oxide (ZnO) nanoparticles using R. fairholmianus root extract to investigate its synergistic cytotoxic effect on MCF-7 cells and explore the possible cell death mechanism. ZnO NPs were synthesized via green synthesis using R. fairholmianus root extract, and the effect on MCF-7 cells was determined by looking at cellular morphology, proliferation, cytotoxicity, apoptosis, and reactive oxygen species (ROS). The results showed that cellular proliferation was reduced following treatment with R. fairholmianus capped zinc oxide nanoparticles (RFZnO NPs), while cytotoxicity and ROS were increased. There was also an increase in apoptosis as indicated by the significant increase in cytoplasmic cytochrome c and caspase 3/7 (markers of apoptosis), as well as increased levels of pro-apoptotic proteins (p53, Bax) and decreased levels of anti-apoptotic protein (Bcl-2). In conclusion, these results showed that RFZnO NPs induce apoptosis in breast cancer cells via a mitochondria-mediated caspase-dependent apoptotic pathway and suggest the use of acetone root extract of R. fairholmianus for the treatment of cancer-related ailments.