Enhanced Oral Delivery of Curcumin via Vitamin E TPGS Modified Nanodiamonds: a Comparative Study on the Efficacy of Non-covalent and Covalent Conjugated Strategies

Inhalable metal-organic framework-mediated cuproptosis combined with PD-L1 checkpoint blockade for lung metastasis synergistic immunotherapy

Cuproptosis shows enormous application prospects in lung metastasis treatment. However, the glycolysis, Cu+ efflux mechanisms, and insufficient lung drug accumulation severely restrict cuproptosis efficacy. Herein, an inhalable poly (2-(N-oxide-N,N-diethylamino)ethyl methacrylate) (OPDEA)-coated copper-based metal-organic framework encapsulating pyruvate dehydrogenase kinase 1 siRNA (siPDK) is constructed for mediating cuproptosis and subsequently promoting lung metastasis immunotherapy, namely OMP. After inhalation, OMP shows highly efficient lung accumulation and long-term retention, ascribing to the OPDEA-mediated pulmonary mucosa penetration. Within tumor cells, OMP is degraded to release Cu2+ under acidic condition, which will be reduced to toxic Cu+ to induce cuproptosis under glutathione (GSH) regulation. Meanwhile, siPDK released from OMP inhibits intracellular glycolysis and adenosine-5'-triphosphate (ATP) production, then blocking the Cu+ efflux protein ATP7B, thereby rendering tumor cells more sensitive to OMP-mediated cuproptosis. Moreover, OMP-mediated cuproptosis triggers immunogenic cell death (ICD) to promote dendritic cells (DCs) maturation and CD8+ T cells infiltration. Notably, OMP-induced cuproptosis up-regulates membrane-associated programmed cell death-ligand 1 (PD-L1) expression and induces soluble PD-L1 secretion, and thus synergizes with anti-PD-L1 antibodies (aPD-L1) to reprogram immunosuppressive tumor microenvironment, finally yielding improved immunotherapy efficacy. Overall, OMP may serve as an efficient inhalable nanoplatform and afford preferable efficacy against lung metastasis through inducing cuproptosis and combining with aPD-L1.

Organic and Biogenic Nanocarriers as Bio-Friendly Systems for Bioactive Compounds' Delivery: State-of-the Art and Challenges

"Green" strategies to build up novel organic nanocarriers with bioperformance are modern trends in nanotechnology. In this way, the valorization of bio-wastes and the use of living systems to develop multifunctional organic and biogenic nanocarriers (OBNs) have revolutionized the nanotechnological and biomedical fields. This paper is a comprehensive review related to OBNs for bioactives' delivery, providing an overview of the reports on the past two decades. In the first part, several classes of bioactive compounds and their therapeutic role are briefly presented. A broad section is dedicated to the main categories of organic and biogenic nanocarriers. The major challenges regarding the eco-design and the fate of OBNs are suggested to overcome some toxicity-related drawbacks. Future directions and opportunities, and finding "green" solutions for solving the problems related to nanocarriers, are outlined in the final of this paper. We believe that through this review, we will capture the attention of the readers and will open new perspectives for new solutions/ideas for the discovery of more efficient and "green" ways in developing novel bioperformant nanocarriers for transporting bioactive agents.

The bioavailability, metabolism and microbial modulation of curcumin-loaded nanodelivery systems

Curcumin (Cur), the major bioactive component of turmeric (Curcuma longa) possesses many health benefits. However, low solubility, stability and bioavailability restricts its applications in food. Recently, nanocarriers such as complex coacervates, nanocapsules, liposomes, nanoparticles, nanomicelles, have been used as novel strategies to solve these problems. In this review, we have focused on the delivery systems responsive to the environmental stimuli such as pH-responsive, enzyme-responsive, targeted-to-specific cells or tissues, mucus-penetrating and mucoadhesive carriers. Besides, the metabolites and their biodistribution of Cur and Cur delivery systems are discussed. Most importantly, the interaction between Cur and their carriers with gut microbiota and their effects of modulating the gut health synergistically were discussed comprehensively. In the end, the biocompatibility of Cur delivery systems and the feasibility of their application in food industry is discussed. This review provided a comprehensive review of Cur nanodelivery systems, the health impacts of Cur nanocarriers and an insight into the application of Cur nanocarriers in food industry.

Folic Acid-Chitosan Oligosaccharide Conjugates Decorated Nanodiamond as Potential Carriers for the Oral Delivery of Doxorubicin

Oral administration of doxorubicin (DOX) is preferred but challenged owing to poor permeability in the gastrointestinal tract (GIT), efflux of P-glycoprotein, short residence time in the intestine, and rapid hydrolysis. Herein, folic acid-chitosan oligosaccharide conjugate (FA-COS)-modified hydroxylated nanodiamond (ND-OH) was designed to enhance the oral bioavailability of DOX. The carboxyl surface of ND was modified into hydroxyl terminal group to increase the colloidal stability of the system under different pH conditions in GIT. FA-COS modification could prolong retention time, endow the drug with sustained release properties, and actively target intestinal FA receptors. In contrast to DOX/ND-OH, the particle size of DOX/ND-OH/FA-COS increased from 189.5 ± 2.8 to 224.5 ± 1.4 nm, and the zeta potential reversed from - 9.1 ± 0.2 to 14.8 ± 0.4 mV. At 48 h, DOX/ND-OH and DOX/ND-OH/FA-COS released 69.07 ± 5.70% and 35.87 ± 5.64%, respectively. FA-COS modification effectively enhanced the cytotoxicity and intracellular uptake of ND-OH/DOX by Caco-2 cells and prolonged intestinal retention in rats. The internalization of DOX/ND-OH and DOX/ND-OH/FA-COS was mainly mediated by energy-dependent clathrin- and caveolae-mediated endocytosis pathways. Pharmacokinetic study demonstrated that the AUC_0-t of DOX/ND-OH and DOX/ND-OH/FA-COS was enhanced by 3.94- and 6.08-fold compared to DOX solution, respectively. These results illustrated that DOX/ND-OH/FA-COS could be an effective strategy to enhance the oral bioavailability of DOX.

The Antibacterial Effect, Biocompatibility, and Osteogenesis of Vancomycin-Nanodiamond Composite Scaffold for Infected Bone Defects

Purpose

The repair and treatment of infected bone defects (IBD) is a common challenge faced by orthopedic clinics, medical materials science, and tissue engineering.

Methods

Based on the treatment requirements of IBD, we utilized multidisciplinary knowledge from clinical medicine, medical materials science, and tissue engineering to construct a high-efficiency vancomycin sustained-release system with nanodiamond (ND) and prepare a composite scaffold. Its effect on IBD treatment was assessed from materials, cytology, bacteriology, and zoology perspectives.

Results

The results demonstrated that the Van-ND-45S5 scaffold exhibited an excellent antibacterial effect, biocompatibility, and osteogenesis in vitro. Moreover, an efficient animal model of IBD was established, and a Van-ND-45S5 scaffold was implanted into the IBD. Radiographic and histological analyses and bone repair-related protein expression, confirmed that the Van-ND-45S5 scaffold had good biocompatibility and osteogenic and anti-infective activities in vivo.

Conclusion

Collectively, our findings support that the Van-ND-45S5 scaffold is a promising new material and approach for treating IBD with good antibacterial effects, biocompatibility, and osteogenesis.

Design and synthesis of new trimethoxylphenyl-linked combretastatin analogues loaded on diamond nanoparticles as a panel for ameliorated solubility and antiproliferative activity

A new series of vinyl amide-, imidazolone-, and triazinone-linked combretastatin A-4 analogues have been designed and synthesised. These compounds have been evaluated for their cytotoxic activity against MDA-MB-231 breast cancer cells. The triazinone-linked combretastatin analogues (6 and 12) exhibited the most potent cytotoxic activity, in sub-micromolar concentration compared with combretastatin A-4 as a reference standard. The results of β-tubulin polymerisation inhibition assay appear to correlate well with the ability to inhibit β-tubulin polymerisation. Additionally, these compounds were subjected to biological assays relating to cell cycle aspects and apoptosis induction. In addition, the most potent compound 6 was loaded on PEG-PCL modified diamond nanoparticles (PEG-PCL-NDs) and F4 was picked as the optimum formula. F4 exhibited enhanced solubility and release over the drug suspension. In the comparative cytotoxic activity, PEG-PCL modified F4 was capable of diminishing the IC50 by around 2.89 times for nude F4, while by 3.48 times relative to non-formulated compound 6.

Optimization of Naringenin Nanoparticles to Improve the Antitussive Effects on Post-Infectious Cough

Naringenin (NRG) is a natural compound with several biological activities; however, its bioavailability is limited owing to poor aqueous solubility. In this study, NRG nanoparticles (NPs) were prepared using the wet media milling method. To obtain NRG NPs with a small particle size and high drug-loading content, the preparation conditions, including stirring time, temperature, stirring speed, and milling media amount, were optimized. The NRG (30 mg) and D-α-tocopherol polyethylene glycol succinate (10 mg) were wet-milled in deionized water (2 mL) with 10 g of zirconia beads via stirring at 50 °C for 2 h at a stirring speed of 300 rpm. As a result, the NRG NPs, with sheet-like morphology and a diameter of approximately 182.2 nm, were successfully prepared. The NRG NPs were stable in the gastrointestinal system and were released effectively after entering the blood circulation. In vivo experiments indicated that the NRG NPs have good antitussive effects. The cough inhibition rate after the administration of the NRG NPs was 66.7%, cough frequency was three times lower, and the potential period was 1.8 times longer than that in the blank model group. In addition, the enzyme biomarkers and histological analysis results revealed that the NRG NPs can effectively regulate the inflammatory and oxidative stress response. In conclusion, the NRG NPs exhibited good oral bioavailability and promoted antitussive and anti-inflammatory effects.

A novel self-nanomicellizing system of empagliflozin for oral treatment of acute pancreatitis: An experimental study

Acute pancreatitis (AP) is a severe inflammatory disorder hampered by a lack of effective drugs in its clinical practice. Empagliflozin (EMP) exhibits potential effects against AP but is limited by poor water-solubility and low bioavailability. Herein, a novel self-nanomicellizing formulation of EMP with phytochemical rebaudioside A (RA) as the nanocarrier (RA-EMP) was fabricated to address these issues. RA-EMP powder could be simply prepared and exhibited excellent storage stability, dramatically improved EMP's apparent solubility, and instantly self-assembled into micelles with high EMP encapsulation efficiency in water. In vivo experimental studies showed that RA-EMP exhibited significantly enhanced oral bioavailability of EMP and dramatically improved therapeutic efficacy against AP. The mechanisms through suppressing the effects of oxidative stress and proinflammatory cytokines were involved in this therapeutic effect. The results demonstrated that RA-EMP could serve as a promising way to enhance the oral bioavailability and strengthen the potential therapeutic efficacy of EMP against AP.

Hybrid lipid core chitosan-TPGS shell nanocomposites as a promising integrated nanoplatform for enhanced oral delivery of sulpiride in depressive disorder therapy

Sulpiride (SUL), a benzamide derivative, acts as a multitarget drug with extensive biological properties. However, being a P-glycoprotein efflux substrate with a limited oral bioavailability imposes a challenge to its clinical efficacy. The current research explores the impact of tailored hybrid lipid-polysaccharide nanocomposites in augmenting the biological performance of SUL. Chitosan-graft-tocopherol polyethylene glycol 1000 succinate (TPGS) copolymers were synthesized and integrated as a polysaccharide shell into a SUL-loaded lipid nanocore. The optimized nanohybrids revealed a nanocore-shell structure with 110.1 nm particle size, 23.7 mV zeta potential, 85.42% encapsulation efficiency, a pH-dependent-release profile, and an acceptable mucoadhesive tendency. Employing TPGS into the chitosan backbone alleviated the cellular internalization of nanohybrids into the Caco-2 intestinal cells and hence increased the intestinal permeation and the oral bioavailability of SUL by 3.3, and 8.7-folds, respectively. Reserpine-induced depression rat model confirmed the superior antidepressant activity of nanohybrids, compared with free SUL and a marketed product. The nanohybrids exhibited 1.87- and 1.47-folds enhancement in both serotonin and dopamine levels, respectively. Additionally, nanohybrids were shown to attenuate brain oxidative stress state and SUL irritant effect on different body tissues. Overall, the newly tailored nanohybrids pave the way for an advance in the field of oral drug delivery.

Surface Modification of Fluorescent Nanodiamonds for Biological Applications

Fluorescent nanodiamonds (FNDs) are a new class of carbon nanomaterials that offer great promise for biological applications such as cell labeling, imaging, and sensing due to their exceptional optical properties and biocompatibility. Implementation of these applications requires reliable and precise surface functionalization. Although diamonds are generally considered inert, they typically possess diverse surface groups that permit a range of different functionalization strategies. This review provides an overview of nanodiamond surface functionalization methods including homogeneous surface termination approaches (hydrogenation, halogenation, amination, oxidation, and reduction), in addition to covalent and non-covalent surface modification with different functional moieties. Furthermore, the subsequent coupling of biomolecules onto functionalized nanodiamonds is reviewed. Finally, biomedical applications of nanodiamonds are discussed in the context of functionalization.

Therapeutic applications of herbal/synthetic/bio-drug in oral cancer: An update

Oral cancer, as one of the most prevalent and invasive cancers that invade local tissue, can cause metastasis, and have high mortality. In 2018, around 355,000 worldwide oral cancers occurred and resulted in 177,000 deaths. Estimates for the year 2020 include about 53,260 new cases added to previous year's cases, and the estimated death toll from this cancer in 2020 is about 10,750 deaths more than previous years. Despite recent advances in cancer diagnosis and treatment, unfortunately, 50% of people with cancer cannot be cured. Of course, it should be remembered that the type of treatment used greatly influences patient recovery. There are not many choices when it comes to treating oral cancer. Research efforts focusing on the discovery and evolution of innovative therapeutic approaches for oral cancer are essential. Such traditional methods of treating this type of cancer like surgery and chemotherapy, have evolved dramatically during the past thirty to forty years, but they continue to cause panic among patients due to their side effects. Therefore, it is necessary to study and use drugs that are less risky for the patient as well as to provide solutions to reduce chemotherapy-induced adverse events that prevent many therapeutic risks. As mentioned above, this study examines low-risk therapies such as herbal remedies, biological drugs, and synthetic drugs in the hope that they will be useful to physicians, researchers, and scientists around the world.