Chitosan/MgO NPs/CQDs bionanocomposite coating: Fabrication, characterization and determination of antimicrobial efficacy.

The development of new polymer nanocomposites or antibacterial coatings is crucial in combating drug-resistant infections, particularly bacterial infections. In this study, a new chitosan polymer based nanocomposite reinforced with magnesium oxide nanopowders and carbon quantum dots was fabricated by sol-gel technique and coated on 316 L stainless steel. In order to gaining the optimal amount of components to achieve the maximum antibacterial properties, the effect of concentration of nanocomposite components on its antibacterial properties was investigated. Crystal structure, microstructure, elemental dispersion, size distribution, chemical composition and morphology of nanocomposite and coating were characterized with various analyses. The obtained results exhibited that the carbon quantum dot and magnesium oxide nanopowders were distributed uniformly and without agglomeration in the chitosan matrix and created a uniform coating. The antibacterial properties of the synthesized samples against Staphylococcus aureus bacteria (gram positive) were evaluated using disk diffusion and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) antibacterial tests. The inhibition growth zone formed around the antibiotic and nanocomposite 25 mg/ml under dark and light was about 32 and 14, 11 mm, respectively. Also, MIC and MBC values for final nanocomposite were 62.5 and 125 µg/ml, respectively.

Dynamic Cross-Linking, Self-Healing, Antibacterial Hydrogel for Regenerating Irregular Cranial Bone Defects.

Given the widespread clinical demand, addressing irregular cranial bone defects poses a significant challenge following surgical procedures and traumatic events. In situ-formed injectable hydrogels are attractive for irregular bone defects due to their ease of administration and the ability to incorporate ceramics, ions, and proteins into the hydrogel. In this study, a multifunctional hydrogel composed of oxidized sodium alginate (OSA)-grafted dopamine (DO), carboxymethyl chitosan (CMCS), calcium ions (Ca2+), nanohydroxyapatite (nHA), and magnesium oxide (MgO) (DOCMCHM) was prepared to address irregular cranial bone defects via dynamic Schiff base and chelation reactions. DOCMCHM hydrogel exhibits strong adhesion to wet tissues, self-healing properties, and antibacterial characteristics. Biological evaluations indicate that DOCMCHM hydrogel has good biocompatibility, in vivo degradability, and the ability to promote cell proliferation. Importantly, DOCMCHM hydrogel, containing MgO, promotes the expression of osteogenic protein markers COL-1, OCN, and RUNX2, and stimulates the formation of new blood vessels by upregulating CD31. This study could provide meaningful insights into ion therapy for the repair of cranial bone defects.

Synergistic effect of green synthesis magnesium oxide nanoparticles and seaweed extract on improving water quality, health benefits, and disease resistance in Nile tilapia.

This study aimed to evaluate the effect of adding liquid extract of algae (Hypnea musciformis, Grateloupia acuminata, and Sargassum muticum) (HGS) and Magnesium oxide nanoparticles (MgO NPs) using this extract to rear water of Oreochromis niloticus, on improving culture water indices, growth performance, digestive enzyme, hemato-biochemical characters, immune, antioxidative responses, and resistance after challenged by Aeromonas hydrophila with specific refer to the potential role of the mixture in vitro as resistance against three strains bacteria (Aeromonas sobria, Pseudomonas fluorescens, P. aeruginosa) and one parasite (Cichlidogyrus tilapia). The first group represented control, HGS0, whereas the other group, HGS5, HGS10, and HGS15 mL-1 of liquid extract, as well as all groups with 7.5 µg mL-1 MgO-NPs added to culture water of O. niloticus, for 60 days. Data showed that increasing levels at HGS 10 and HGS15 mL-1 in to-culture water significantly enhanced growth-stimulating digestive enzyme activity and a significantly improved survival rate of O. niloticus after being challenged with A. hydrophila than in the control group. The total viability, coliform, fecal coliform count, and heavy metal in muscle partially decreased at HGS 10 and HGS15 mL-1 than in the control group. Correspondingly, the highest positive effect on hemato-biochemical indices was noticed at levels HGS 10 and HGS15 mL-1. Fish noticed an improvement in immune and antioxidant indices compared to control groups partially at HGS 10 and HGS15 mL-1. Interestingly, fish cultured in rearing water with the mixture provided downregulated the related inflammatory genes (HSP70, TNF, IL-1ß, and IL-8) partially at HGS15 mL-1. In vitro, the mixture showed positive efficiency as an antibacterial and partially antiparasitic at HGS 10 and HGS15 mL-1. This study proposes utilizing a mixture of (HGS) and (MgO-NPs) with optimum levels of 10-15 mL-1 in cultured water to improve water indices, growth, health status, and increased resistance of O. niloticus against bacterial and parasitic infection.

Hyaluronic Acid-Modified Spherical MgO2/Pd Nanocomposites Exhibit Superior Antitumor Effect through Tumor Microenvironment-Responsive Ferroptosis Induction and Photothermal Therapy.

Metal peroxide nanomaterials as efficient hydrogen peroxide (H2O2) self-supplying agents have attracted the attention of researchers for antitumor treatment. However, relying solely on metal peroxides to provide H2O2 is undoubtedly insufficient to achieve optimal antitumor effects. Herein, we construct novel hyaluronic acid (HA)-modified nanocomposites (MgO2/Pd@HA NCs) formed by decorating palladium nanoparticles (Pd NPs) onto the surfaces of a magnesium peroxide (MgO2) nanoflower as a highly effective nanoplatform for the tumor microenvironment (TME)-responsive induction of ferroptosis in tumor cells and tumor photothermal therapy (PTT). MgO2/Pd@HA NC could be well endocytosed into tumor cells with CD44 expression depending on the specific recognition of HA with CD44, and then, the nanocomposites can be rapidly decomposed in mild acid and hyaluronidase overexpressed TME, and plenty of H2O2 was released. Simultaneously, Pd NPs catalyze self-supplied H2O2 to generate abundant hydroxyl radicals (•OH) and catalyze glutathione (GSH) into glutathione disulfide owing to its peroxidase and glutathione oxidase mimic enzyme activities, while the abundant •OH could also consume GSH in tumor cells and disturb the defense pathways of ferroptosis leading to the accumulation of lipid peroxidation and resulting in the occurrence of ferroptosis. Additionally, the superior photothermal conversion performance of Pd NPs in near-infrared II could also be used for PTT, synergistically cooperating with nanocomposite-induced ferroptosis for tumor inhibition. Consequently, the successfully prepared TME-responsive MgO2/Pd@HA NCs exhibited marked antitumor effect without obvious biotoxicity, contributing to thoroughly explore the nanocomposites as a novel and promising treatment for tumor therapy.

Magnesium-oxide-enhanced bone regeneration: 3D-printing of gelatin-coated composite scaffolds with sustained Rosuvastatin release.

Critical-size bone defects are one of the main challenges in bone tissue regeneration that determines the need to use angiogenic and osteogenic agents. Rosuvastatin (RSV) is a class of cholesterol-lowering drugs with osteogenic potential. Magnesium oxide (MgO) is an angiogenesis component affecting apatite formation. This study aims to evaluate 3D-printed Polycaprolactone/ß-tricalcium phosphate/nano-hydroxyapatite/ MgO (PCL/ß-TCP/nHA/MgO) scaffolds as a carrier for MgO and RSV in bone regeneration. For this purpose, PCL/ß-TCP/nHA/MgO scaffolds were fabricated with a 3D-printing method and coated with gelatin and RSV. The biocompatibility and osteogenicity of scaffolds were examined with MTT, ALP, and Alizarin red staining. Finally, the scaffolds were implanted in a bone defect of rat's calvaria, and tissue regeneration was investigated after 3 months. Our results showed that the simultaneous presence of RSV and MgO improved biocompatibility, wettability, degradation rate, and ALP activity but decreased mechanical strength. PCL/ß-TCP/nHA/MgO/gelatin-RSV scaffolds produced sustained release of MgO and RSV within 30 days. CT images showed that PCL/ß-TCP/nHA/MgO/gelatin-RSV scaffolds filled approximately 86.83 + 4.9 % of the defects within 3 months and improved angiogenesis, woven bone, and osteogenic genes expression. These results indicate the potential of PCL/ß-TCP/nHA/MgO/gelatin-RSV scaffolds as a promising tool for bone regeneration and clinical trials.

Engineered MgO nanoparticles for cartilage-bone synergistic therapy.

The emerging therapeutic strategies for osteoarthritis (OA) are shifting toward comprehensive approaches that target periarticular tissues, involving both cartilage and subchondral bone. This shift drives the development of single-component therapeutics capable of acting on multiple tissues and cells. Magnesium, an element essential for maintaining skeletal health, shows promise in treating OA. However, the precise effects of magnesium on cartilage and subchondral bone are not yet clear. Here, we investigated the therapeutic effect of Mg2+ on OA, unveiling its protective effects on both cartilage and bone at the cellular and animal levels. The beneficial effect on the cartilage-bone interaction is primarily mediated by the PI3K/AKT pathway. In addition, we developed poly(lactic-co-glycolic acid) (PLGA) microspheres loaded with nano-magnesium oxide modified with stearic acid (SA), MgO&SA@PLGA, for intra-articular injection. These microspheres demonstrated remarkable efficacy in alleviating OA in rat models, highlighting their translational potential in clinical applications.

Effect of magnesium oxide nanoparticles and LED irradiation on the viability and differentiation of human stem cells of the apical papilla.

PURPOSE: Currently, regenerative endodontic treatments are gaining more and more attention, and stem cells play a significant role in these treatments. In order to enhance stem cell proliferation and differentiation, a variety of methods and materials have been used. The purpose of this study was to determine the effects of magnesium oxide nanoparticles and LED irradiation on the survival and differentiation of human stem cells from apical papilla. METHODS: The MTT test was used to measure the cell survival of SCAPs that had been exposed to different concentrations of magnesium oxide nanoparticles after 24 and 48 h, and the concentration with the highest cell survival rate was picked for further studies. The cells were classified into four distinct groups based on their treatment: (1) control, which received no exposure, (2) exposure to magnesium oxide nanoparticles, (3) exposure to light emitting diode (LED) irradiation (635 nm, 200 mW/cm2) for 30 s, (4) exposure simultaneously with magnesium oxide nanoparticles and LED irradiation. A green approach was employed to synthesize magnesium oxide nanoparticles. Quantitative real time PCR was used to measure the gene expression of osteo/odontogenic markers such as BSP, DSPP, ALP and DMP1 in all four groups after treatment, and Alizarin red S staining (ARS) was used to determine the osteogenic differentiation of SCAPs by demonstrating the Matrix mineralization. RESULTS: The highest viability of SCAPs was observed after 24 h in concentration 1 and 10 µg/mL and after 48 h in concentration 1 µg/mL, which were not significantly different from the control group. In both times, the survival of SCAPs decreased with increasing concentration of magnesium oxide nanoparticles (MgONPs). According to the results of Real-time PCR, after 24 and 48 h, the highest differentiation of BSP, DMP1, ALP and DSPP genes was observed in the LED + MgONPs group, followed by MgONPs and then LED, and in all 3 experimental groups, it was significantly higher than control group (P < 0.05). Also, after 24 and 48 h, the density of ARS increased in all groups compared to the control group, and the highest density was observed in the MgONPs + LED and MgONPs groups. CONCLUSION: This research concluded that exposure to SCAPs, MgONPs, and LED irradiation has a significant effect on enhancing gene expression of odontogenic/osteogenic markers and increasing matrix mineralization.

Vitamin D3 Release from MgO Doped 3D Printed TCP Scaffolds for Bone Regeneration.

Regenerating bone tissue in critical-sized craniofacial bone defects remains challenging and requires the implementation of innovative bone implants with early stage osteogenesis and blood vessel formation. Vitamin D3 is incorporated into MgO-doped 3D-printed scaffolds for defect-specific and patient-specific implants in low load-bearing areas. This novel bone implant also promotes early stage osteogenesis and blood vessel development. Our results show that vitamin D3-loaded MgO-doped 3D-printed scaffolds enhance osteoblast cell proliferation 1.3-fold after being cultured for 7 days. Coculture studies on osteoblasts derived from human mesenchymal stem cells (hMSCs) and osteoclasts derived from monocytes show the upregulation of genes related to osteoblastogenesis and the downregulation of RANK-L, which is essential for osteoclastogenesis. Release of vitamin D3 also inhibits osteoclast differentiation by 1.9-fold after a 21-day culture. After 6 weeks, vitamin D3 release from MgO-doped 3D-printed scaffolds enhances the new bone formation, mineralization, and angiogenic potential. The multifunctional 3D-printed scaffolds can improve early stage osteogenesis and blood vessel formation in craniofacial bone defects.

Methylglyoxal activates transient receptor potential A1/V1 via reactive oxygen species in the spinal dorsal horn.

Methylglyoxal (MGO), a highly reactive dicarbonyl metabolite of glucose primarily formed during the glycolytic pathway, is a precursor of advanced glycation end-products (AGEs). Recently, numerous studies have shown that MGO accumulation can cause pain and hyperalgesia. However, the mechanism through which MGO induces pain in the spinal dorsal horn remains unclear. The present study investigated the effect of MGO on spontaneous excitatory postsynaptic currents (sEPSC) in rat spinal dorsal horn neurons using blind whole-cell patch-clamp recording. Perfusion of MGO increased the frequency and amplitude of sEPSC in spinal horn neurons in a concentration-dependent manner. Additionally, MGO administration increased the number of miniature EPSC (mEPSC) in the presence of tetrodotoxin, a sodium channel blocker. However, 6-cyano-7-nitroqiunocaline-2,3-dione (CNQX), an AMPA/kainate receptor antagonist, blocked the enhancement of sEPSC by MGO. HC-030031, a TRP ankyrin-1 (TRPA1) antagonist, and capsazepine, a TRP vanilloid-1 (TRPV1) antagonist, inhibited the action of MGO. Notably, the effects of MGO were completely inhibited by HC-030031 and capsazepine. MGO generates reactive oxygen species (ROS) via AGEs. ROS also potentially induce pain via TRPA1 and TRPV1 in the spinal dorsal horn. Furthermore, we examined the effect of MGO in the presence of N-tert-butyl-α-phenylnitrone (PBN), a non-selective ROS scavenger, and found that the effect of MGO was completely inhibited. These results suggest that MGO increases spontaneous glutamate release from the presynaptic terminal to spinal dorsal horn neurons through TRPA1, TRPV1, and ROS and could enhance excitatory synaptic transmission.

Magnesium nanoparticles extirpate salt stress in carrots (Daucus carota L.) through metabolomics regulations.

Underground vegetables are sensitive and vulnerable to salt stress. The vegetables are the main source of vitamins, nutrients and minerals in human diet. Also contain healthy carbohydrates, antioxidant and resistant starch which are beneficial for human health. Salinity influences water balance, morphological appearance and cellular interference of crop plants. It also caused disproportion of nutrients which usually affects the physiochemical processes in plant. Salt stress also affect biochemical attributes and hampers the growth of underground organs, due to which yield of crop decreased. The nanoparticles had been potentially used for better crop yield, in the recent. In our research study, we elaborate the positive response of magnesium oxide nanoparticles (MgO-NPs) on the morphological and biochemical parameters as well as anti-oxidant enzymes action on two accessions of carrot (Daucus carota L.) under salt stress of 40 mM and 80 mM. In a pilot experiment, various levels (0, 50, 100, 150, 200 and 250 mg/L) of MgO-NPs were tested through foliar application on carrot plants. Foliar application of MgO-NPs at concentration of 150 mg/L was most effective treatment and ameliorate the salt stress in both carrot accessions (DC-03 and DC-90). The MgO-NPs significantly enhanced the morphological and biochemical parameters. The yield was significantly increased with the exposure of MgO-NPs. Our results thus confirmed the potential of MgO-NPs to endorse the plant development and growth under salinity. However, further research study is needed to explore effectiveness of MgO-NPs in various other plants for the ameliorant of salinity.

Differential responses of Brassica napus cultivars to dual effects of magnesium oxide nanoparticles.

Magnesium oxide nanoparticles (MgO NPs) have great potential to enhance the crop productivity and sustainability of agriculture. Still, a thorough understanding is lacking about its essentiality or toxicity and precise dose for the safe cultivation of oilseed crops. Thus, we assessed the dual effects of MgO NPs (control, 5, 10, 20, 40, 80, and 200 mg/L) on the seed germination, growth performance, photosynthesis, total soluble protein, total carbohydrates, oxidative stress markers (hydrogen peroxide as H2O2 and superoxide anion as O2•‒), lipid peroxidation as MDA, and antioxidant defence machinery (SOD, CAT, APX, and GR activities, and GSH levels) of seven different oilseeds (Brassica napus L.) cultivars (ZY 758, ZD 649, ZD 635, ZD 619, GY 605, ZD 622, and ZD 630). Our findings revealed that low doses of MgO NPs (mainly at 10 mg/L) markedly boosted the seed germination, plant growth (shoot and root lengths) (15‒22%), and biomass (fresh and dry) (11‒19%) by improving the levels of photosynthetic pigments (14‒27%), net photosynthetic rate, stomatal conductance, photosynthetic efficiency (Fv/Fm), total soluble protein and total carbohydrates (16‒36%), antioxidant defence, and reducing the oxidative stress in B. napus tissues. Among all B. napus cultivars, these beneficial effects of MgO NPs were pronounced in ZD 635. ile, elevated levels of MgO NPs (particularly at 200 mg/L) induced oxidative stress, impaired antioxidant scavenging potential, photosynthetic inhibition, protein oxidation, and carbohydrate degradation and lead to inhibit the plant growth attributes. These inhibitory effects were more pronounced in ZD 622. Collectively, low-dose MgO NPs reinforced the Mg contents, protected the plant growth, photosynthesis, total soluble carbohydrates, enzyme activities, and minimized the oxidative stress. While, the excessive MgO NP levels impaired the above-reported traits. Overall, ZD 622 was highly susceptible to MgO NP toxicity and ZD 635 was found most tolerant to MgO NP toxicity.

Drug kinetics and antimicrobial properties of quaternary bioactive glasses 81S(81SiO2-(16-x)CaO-2P2O5-1Na2O-xMgO); an in-vitro study.

Bioactive glasses have recently been attracted to meet the challenge in bone tissue regeneration, repair, healing, dental implants, etc. Among the conventional bio-glasses, a novel quaternary mesoporous nano bio-glass with composition 81S(81SiO2-(16-x)CaO-2P2O5-1Na2O-xMgO) (x = 0, 1.6, 2.4, 4 and 8 mol%) employing Stober's method has been explored for examining the above potential application through in-vitro SBF assay, MTT assay, antimicrobial activity and drug loading and release ability. With increasing the MgO concentration up to 4 mol%, from in-vitro SBF assay, we observe that HAp layer develops on the surface of the nBGs confirmed from XRD, FTIR and FESEM. MTT assay using MG-63 cells confirms the biocompatibility of the nBGs having cell viability >225 % for MGO_4 after 72 h which is more than the clinically used 45S5 bio-glass. We have observed cell viability of >125 % even after 168 h. Moreover, MGO_4 is found to restrict the growth of E. coli by 65 % while S. aureus by 75 %, confirming the antimicrobial activity. Despite an increase in the concentration of magnesium, nBGs are found to be non-toxic towards the RBCs up to 4 mol% of MgO while for 8 %, the hemolysis percentage is >6 % which is toxic. Being confirmed MGO_4 nBG as a bioactive material, various concentrations of drug (Dexamethasone (DEX)) loading and release kinetics are examined. We show that 80 % of loading in case of 10 mg-ml-1 and 70 % of cumulative release in 100 h. The mesoporous structure of MGO_4 having an average pore diameter of 5 nm and surface area of 216 m2 g-1 confirmed from BET supports the loading and release kinetics. We conclude that the quaternary MGO_4 nBG may be employed effectively for bone tissue regeneration due to its high biocompatibility, excellent in-vitro cell viability, antimicrobial response and protracted drug release.