Fabrication of BSA-Green Tea Polyphenols-Chitosan Nanoparticles and Their Role in Radioprotection: A Molecular and Biochemical Approach

Construction of Phlorotannin-Based Nanoparticles for Alleviating Acute Liver Injury

Acute liver injury (ALI) is a severe health condition with limited treatment options. Phlorotannin (PT), a natural compound extracted from seaweeds, has shown potential in improving liver function. However, its poor stability and bioavailability have limited its applications in vivo. In this study, we developed PT-based nanoparticles (NPs) through a Mannich reaction with glycine, which exhibited good biocompatibility and prolonged circulation time in vivo. Our results revealed that the PT NPs possess strong free radical scavenging ability, effectively reducing reactive oxygen species (ROS) and alleviating oxidative stress and proinflammatory responses in the H2O2-induced oxidative damage model of HepG2 cells. Furthermore, the PT NPs effectively attenuated oxidative stress and inflammation in the liver tissue of carbon tetrachloride (CCl4)-induced liver injury mice by regulating the Nrf2/HO-1 signaling pathway. In summary, our results suggested that the PT NPs could serve as a promising nano-therapeutic strategy for alleviating ALI.

Nanodrugs with intrinsic radioprotective exertion: Turning the double-edged sword into a single-edged knife

Ionizing radiation (IR) poses a growing threat to human health, and thus ideal radioprotectors with high efficacy and low toxicity still receive widespread attention in radiation medicine. Despite significant progress made in conventional radioprotectants, high toxicity, and low bioavailability still discourage their application. Fortunately, the rapidly evolving nanomaterial technology furnishes reliable tools to address these bottlenecks, opening up the cutting-edge nano-radioprotective medicine, among which the intrinsic nano-radioprotectants characterized by high efficacy, low toxicity, and prolonged blood retention duration, represent the most extensively studied class in this area. Herein, we made the systematic review on this topic, and discussed more specific types of radioprotective nanomaterials and more general clusters of the extensive nano-radioprotectants. In this review, we mainly focused on the development, design innovations, applications, challenges, and prospects of the intrinsic antiradiation nanomedicines, and presented a comprehensive overview, in-depth analysis as well as an updated understanding of the latest advances in this topic. We hope that this review will promote the interdisciplinarity across radiation medicine and nanotechnology and stimulate further valuable studies in this promising field.

Protein-polysaccharides based nanoparticles for loading with Malus baccata polyphenols and their digestibility in vitro

The poor solubility, instability and low absorption rate obstruct the bioavailability of polyphenols isolated from Malus baccata (MBP) during gastrointestinal digestion. In order to solve the limitable problems, the food-grade nanoparticles were fabricated by mucin (MC) and Hohenbuehelia serotina polysaccharides (HSP) for delivery of MBP (MBP-NPs). The physicochemical properties and morphology of MBP-NPs prepared by different condition were respectively characterized. During gastrointestinal digestion in vitro, the release characteristic and variation in phenolic composition of MBP-NPs were evaluated. The results showed that MBP-NPs formed by hydrogen bonding and hydrophobic interaction possessed the regularly spherical shapes and smooth surfaces and semi-crystalline properties. Moreover, MBP-NPs presented the excellent physicochemical stability. During simulated gastrointestinal digestion in vitro, MBP-NPs exhibited the sustained release characteristics of phenolic compounds, which were confirmed by SDS-PAGE measurement. Compared with that of unencapsulated MBP, the significant variation was occurred in the phenolic composition of MBP-NPs, indicating that MBP-NPs could prevent the degradation and transformation of phenolic compounds. This study provides a novel strategy to improve the bioavailability of polyphenols.

Simultaneous Administration of Bevacizumab with Bee-Pollen Extract-Loaded Hybrid Protein Hydrogel NPs Is a Promising Targeted Strategy against Cancer Cells

Bevacizumab (Bev) a humanized monoclonal antibody that fights vascular endothelial growth factor A (VEGF-A). It was the first specifically considered angiogenesis inhibitor and it has now become the normative first-line therapy for advanced non-small-cell lung cancer (NSCLC). In the current study, polyphenolic compounds were isolated from bee pollen (PCIBP) and encapsulated (EPCIBP) inside moieties of hybrid peptide-protein hydrogel nanoparticles in which bovine serum albumin (BSA) was combined with protamine-free sulfate and targeted with folic acid (FA). The apoptotic effects of PCIBP and its encapsulation (EPCIBP) were further investigated using A549 and MCF-7 cell lines, providing significant upregulation of Bax and caspase 3 genes and downregulation of Bcl2, HRAS, and MAPK as well. This effect was synergistically improved in combination with Bev. Our findings may contribute to the use of EPCIBP simultaneously with chemotherapy to strengthen the effectiveness and minimize the required dose.

Effect of chitosan-oleuropein nanoparticles on dentin collagen cross-linking

BACKGROUND

The integrity and stability of collagen are crucial for the dentin structure and bonding strength at dentin-resin interface. Natural plant-derived polypehenols have been used as collagen crosslinkers.

OBJECTIVE

The aims of the study were to develop novel chitosan oleuropein nanoparticles (CS-OL-NPs), and to investigate the CS-OL-NPs treated dentin's the resistance to enzymatic degradation and mechanic property.

METHODS

CS-OL-NPs were developed using the ionotropic gelation method. Release and biocompatibility of the CS-OL-NPs were tested. Twenty demineralized dentin collage specimens were randomized into four interventions groups: A, Deionized Water (DW); B, 5% glutaraldehyde solution (GA); C, 1 mg/ml chitosan (CS); and D, 100 mg/L CS-OL-NPs. After 1-min interventions, dentin matrix were evaluated by the micro-Raman spectroscopy for the modulus of elasticity test. Collagen degradation was assessed using hydroxyproline (HYP) assay.

RESULTS

CS-OL-NPs were spherical core-shape with a size of 161.29 ± 8.19 nm and Zeta potential of 19.53 ± 0.26 mV. After a burst release of oleuropein in the initial 6 h, there was a long-lasting steady slow release. CS-OL-NPs showed a good biocompatibility for the hPDLSCs. The modulus of elasticity in the crosslinked groups were significantly higher than that in the control group (P< 0.05 for all). The specimens treated with CS-OL-NP showed a greater modulus of elasticity than those treated with GA and CS (P< 0.05 for both). The release of HYP in the crosslinked group was significantly lower than that in the non-crosslinked groups (P< 0.05 for all).

CONCLUSION

CS-OL-NPs enhanced the dentin mechanical property and resistance to biodegradation, with biocompatibility and potential for clinical application.

Role of Nrf2 Signaling Cascade in Breast Cancer: Strategies and Treatment

Breast cancer is the second leading cancer among all types of cancers. It accounts for 12% of the total cases of cancers. The complex and heterogeneous nature of breast cancer makes it difficult to treat in advanced stages. The expression of various enzymes and proteins is regulated by several molecular pathways. Oxidative stress plays a vital role in cellular events that are generally regulated by nuclear factor erythroid 2-related factor 2 (Nrf2). The exact mechanism of Nrf2 behind cytoprotective and antioxidative properties is still under investigation. In healthy cells, Nrf2 expression is lower, which maintains antioxidative stress; however, cancerous cells overexpress Nrf2, which is associated with various phenomena, such as the development of drug resistance, angiogenesis, development of cancer stem cells, and metastasis. Aberrant Nrf2 expression diminishes the toxicity and potency of therapeutic anticancer drugs and provides cytoprotection to cancerous cells. In this article, we have discussed the attributes associated with Nrf2 in the development of drug resistance, angiogenesis, cancer stem cell generation, and metastasis in the specific context of breast cancer. We also discussed the therapeutic strategies employed against breast cancer exploiting Nrf2 signaling cascades.

Bioactive compounds: Application of albumin nanocarriers as delivery systems

Enriched products with bioactive compounds (BCs) show the capacity to produce a wide range of possible health effects. Most BCs are essentially hydrophobic and sensitive to environmental factors; so, encapsulation becomes a strategy to solve these problems. Many globular proteins have the intrinsic ability to bind, protect, encapsulate, and introduce BCs into nutraceutical or pharmaceutical matrices. Among them, albumins as human serum albumin (HSA), bovine serum albumin (BSA), ovalbumin (OVA) and α-lactalbumin (ALA) are widely abundant, available, and applied in many industrial sectors, becoming promissory materials to encapsulate BCs. Therefore, this review focuses on researches about the main groups of natural origin BCs (namely phenolic compounds, lipids, vitamins, and carotenoids), the different types of nanostructures based on albumins to encapsulate them and the main fields of application for BCs-loaded albumin systems. In this context, phenolic compounds (catechins, quercetin, and chrysin) are the most extensively BCs studied and encapsulated in albumin-based nanocarriers. Other extensively studied subgroups are stilbenes and curcuminoids. Regarding lipids and vitamins; terpenes, carotenoids (β-carotene), and xanthophylls (astaxanthin) are the most considered. The main application areas of BCs are related to their antitumor, anti-inflammatory, and antioxidant properties. Finally, BSA is the most used albumin to produced BCs-loaded nanocarriers.

Development of nanotechnology-mediated precision radiotherapy for anti-metastasis and radioprotection

Radiotherapy (RT), including external beam RT and internal radiation therapy, uses high-energy ionizing radiation to kill tumor cells.

Recent insights on tea metabolites, their biosynthesis and chemo-preventing effects: A review

Tea manufactured from the cultivated shoots of Camellia sinensis (L.) O. Kuntze is the most commonly consumed nonalcoholic drink around the world. Tea is an agro-based, environmentally sustainable, labor-intensive, job-generating, and export-oriented industry in many countries. Tea includes phenolic compounds, flavonoids, alkaloids, vitamins, enzymes, crude fibers, protein, lipids, and carbohydrates, among other biochemical constituents. This review described the nature of tea metabolites, their biosynthesis and accumulation with response to various factors. The therapeutic application of various metabolites of tea against microbial diseases, cancer, neurological, and other metabolic disorders was also discussed in detail. The seasonal variation, cultivation practices and genetic variability influence tea metabolite synthesis. Tea biochemical constituents, especially polyphenols and its integral part catechin metabolites, are broadly focused on potential applicability for their action against various diseases. In addition to this, tea also contains bioactive flavonoids that possess health-beneficial effects. The catechin fractions, epigallocatechin 3-gallate and epicatechin 3-gallate, are the main components of tea that has strong antioxidant and medicinal properties. The synergistic function of natural tea metabolites with synthetic drugs provides effective protection against various diseases. Furthermore, the application of nanotechnologies enhanced bioavailability, enhancing the therapeutic potential of natural metabolites against numerous diseases and pathogens.

Radioprotective effect of a novel and green bio-nanohybrid, chitosan/silver/cobalt complex, based on Ferulago angulate plant

A novel bio-nanocomposite was developed by incorporating the extracted nanochitosan from shrimp wastes with Schiff base cobalt complex (Chit-Co complex). The phytosynthesis of Chit-Co complex/Ag bio-nanocomposite was designed utilizing Chit-Co complex at the presence of Ferulago angulate extraction and characterized by AFM, SEM, EDAX, TEM, FT-IR, and elemental analysis. The radioprotective application of this bio-nanocomposite on human lymphocyte cells was evaluated using micronucleus (MN) assay. Total antioxidant activities of it were evaluated using FRAP and DPPH assays. Chit-Co complex/Ag bio-nanocomposite significantly decreased the frequency of micronuclei in human lymphocytes exposed to ionization irradiation (IR). The highest protection was observed at 200 μg/ml. Also, maximum antioxidant activities of bio-nanocomposite were provided at the same dose. These data exhibit the radioprotective effect of a bio-nanocomposite based on wastes of living organisms can be an excellent radioprotective agent, which can protect the normal cells of human against the genetic damage by IR.

Advances in Nanodelivery of Green Tea Catechins to Enhance the Anticancer Activity

Cancer is one of the leading causes of death globally. A variety of phenolic compounds display preventative and therapeutic effects against cancers. Green teas are rich in phenolics. Catechins are the most dominant phenolic component in green teas. Studies have shown that catechins have anticancer activity in various cancer models. The anticancer activity of catechins, however, may be compromised due to their low oral bioavailability. Nanodelivery emerges as a promising way to improve the oral bioavailability and anticancer activity of catechins. Research in this area has been actively conducted in recent decades. This review provides the molecular mechanisms of the anticancer effects of catechins, the factors that limit the oral bioavailability of catechins, and the latest advances of delivering catechins using nanodelivery systems through different routes to enhance their anticancer activity.

Evaluating the radioprotective effect of single dose and daily oral consumption of green tea, grape seed, and coffee bean extracts against gamma irradiation

INTRODUCTION

The aim of this study was to investigate and compare the radio-protective effect of green tea, grape seed, and coffee bean extracts in different oral consumption methods in mice.

MATERIALS AND METHODS

In this experimental-quantitative study 150 mice in 15 equally sized groups were used. For each extract, two groups received 200 mg/kg of herbal extracts' combination for 7 and 30 consecutive days before irradiation, and one group received 800 mg/kg of the extract 2 h before irradiation (3 Gy gamma-rays of Co-60). The similar groups were classified to receive a combination of the plant extracts (green tea, grape seed, and coffee bean). Irradiation without consuming plant extract (irradiated group), and a control group were also devised. Alkaline comet and micronucleus assays were used to investigate the radioprotective effect on mice blood and bone marrow cells, respectively.

RESULTS

Consumption of all plant extracts significantly decreased the radiation damage to blood and bone marrow cells, compared to the irradiated group (p < 0.01), with grape seed extract showing higher protective effect. Continuous daily oral consumption (one week/month) showed a significant higher radioprotective effect compared to single consumption (p < 0.05). Continuous consumption of the combination of the extracts showed a higher radio-protection in comparison to each of the plant extracts (p < 0.03).

CONCLUSIONS

The radioprotective effect of continuous consumption (for one week/month) of the plant extracts was greater than single dose. In continuous consumption protocols, we found the synergetic property and higher radioprotective effect of the plant extract combination compared to each one.

Chitosan coated pH-responsive metal-polyphenol delivery platform for melanoma chemotherapy

The safe and effective drug delivery system is important for cancer therapy. Here in, we first constructed a delivery system Cabazitaxel(Cab)@MPN/CS between metal-polyphenol (MPN) and chitosan (CS) to deliver Cab for melanoma therapy. The preparation process is simple, green, and controllable. After introducing CS coating, the drug loading was improved from 7.56 % to 9.28 %. Cab@MPN/CS NPs released Cab continuously under acid tumor microenvironment. The zeta potential of Cab@MPN/CS NPs could be controlled by changing the ratio of Cab@MPN and CS solutions. The positively charged Cab@MPN/CS accelerate B16F10 cell internalization. After internalized, Cab@MPN/CS NPs could escape from lysosomes via the proton sponge effect. The permeability of CS promotes the penetration of Cab@MPN/CS to the deeper B16F10 tumor spheroids. In vivo results showed that Cab@MPN/CS NPs have a longer retention time in tumor tissues and significantly inhibit tumor growth by up-regulating TUNEL expression and down-regulating KI67 and CD31 expression. Thus, this delivery system provides a promising strategy for the tumor therapy in clinic.

Measuring the concentration of protein nanoparticles synthesized by desolvation method: Comparison of Bradford assay, BCA assay, hydrolysis/UV spectroscopy and gravimetric analysis

The desolvation technique is one of the most popular methods for preparing protein nanoparticles for medicine, biotechnology, and food applications. We fabricated 11 batches of BSA nanoparticles and 2 batches of gelatin nanoparticles by desolvation method. BSA nanoparticles from 2 batches were cross-linked by heating at +70 °C for 2 h; other nanoparticles were stabilized by glutaraldehyde. We compared several analytical approaches to measuring their concentration: gravimetric analysis, bicinchoninic acid assay, Bradford assay, and alkaline hydrolysis combined with UV spectroscopy. We revealed that the cross-linking degree and method of cross-linking affect both Bradford and BCA assay. Direct measurement of protein concentration in the suspension of purified nanoparticles by dye-binding assays can lead to significant (up to 50-60%) underestimation of nanoparticle concentration. Quantification of non-desolvated protein (indirect method) is affected by the presence of small nanoparticles in supernatants and can be inaccurate when the yield of desolvation is low. The reaction of cross-linker with protein changes UV absorbance of the latter. Therefore pure protein solution is an inappropriate calibrator when applying UV spectroscopy for the determination of nanoparticle concentration. Our recommendation is to determine the concentration of protein nanoparticles by at least two different methods, including gravimetric analysis.

Iron oxide nanoparticle-induced hematopoietic and immunological response in rats

The application and use of iron oxide nanoparticless (IONPs) in the biomedical field are steadily increasing, although it remains uncertain whether IONPs are safe or should be used with caution. In the present study, we investigated the toxicity profile of ultrafine IONPs in rats administered with 7.5, 15 and 30 mg IONPs/kg body wt intravenously once a week for 4 weeks. IONP treatment reduces bone marrow-mononuclear cell proliferation, increases free radical species and DNA damage leading to growth arrest and subsequently apoptosis induction at 15 and 30 mg doses. It also induces apoptosis in undifferentiated hematopoietic stem cells. IONP treatment significantly increased the pro-inflammatory cytokine (Interleukin (IL)-1β, TNF-α, and IL-6) level in serum. The induction in inflammation was likely mediated by splenic M1 macrophages (IL-6 and TNF-α secretion). IONP treatment induces splenocyte apoptosis and alteration in the immune system represented by reduced CD4+/CD8+ ratio and increased B cells. It also reduces innate defense represented by lower natural killer cell cytotoxicity. IONP administration markedly increased lipid peroxidation in the spleen, while the glutathione level was reduced. Similarly, superoxide dismutase activity was increased and catalase activity was reduced in the spleen of IONP-treated rats. At an organ level, IONP treatment did not cause any significant injury or structural alteration in the spleen. Collectively, our results suggest that a high dose of ultrafine IONPs may cause oxidative stress, cell death, and inflammation in a biological system.

The enhancement of N-acetylcysteine on intestinal absorption and oral bioavailability of hydrophobic curcumin

To solve the low oral bioavailability of curcumin (CUR) due to the limits imposed by gastrointestinal (GI) barrier, we constructed a nano delivery system to evaluate the effect of N-acetyl-L-cysteine (NAC) on intestinal absorption and oral bioavailability of CUR. CUR was first encapsulated in bovine serum albumin nanoparticles (CUR-BSA-NPs), and then was further modified by NAC (CUR-NBSA-NPs). In situ single-pass intestinal perfusion assay demonstrated that CUR-NBSA-NPs displayed excellent permeation and absorption rates in GI tract. Additionally, the distribution study in GI tract revealed that more NBSA-NPs were absorbed by intestinal segments compared to the BSA nanoparticles. Plasma concentration-time curves in rats showed that AUC_0-t, C_max and MRT_0-t values of CUR after oral administration of CUR-NBSA-NPs were increased to 3.25-, 4.42-, and 1.43-fold compared with that of CUR suspension. In conclusion, NAC promotes oral absorption of CUR, thereby improving its oral bioavailability.

Preparation of Strong Antioxidative, Therapeutic Nanoparticles Based on Amino Acid-Induced Ultrafast Assembly of Tea Polyphenols

Nanoformulations offer the opportunity to overcome the shortcomings of drug molecules, such as low solubility, side effects, insufficient stability, etc., but in most of the current nanomedicines, nanocarriers as excipients do not directly participate in the therapy procedure. Accordingly, it is promising to develop the nanotherapeutics composed entirely of pharmaceutically active molecules. Tea polyphenols, especially epigallocatechin gallate (EGCG), are a kind of natural antioxidants with various biological and health beneficial effects and are extensively investigated as nutrients and anticancer drugs. Here, the size-tunable and highly active polyphenol nanoparticles were conveniently synthesized in water and could be massively produced with a simple facility. Compared to the previous strategies, either molecular assembly via oxidative coupling or combination with other biomacromolecules, the present preparation was conducted by the amino acid-triggered Mannish condensation reactions, thus permitting the flexible molecular design of various polyphenol nanoparticles by selecting different amino acids. This straightforward and ultrafast method actually opens up a novel means to make use of naturally reproducible polyphenols. Moreover, inheriting the salient properties of EGCG, these nanoparticles show strong antioxidation capacity, 10-fold higher than the extensively investigated polydopamine nanoparticles, and they are biosafe but have therapeutic effects, according to the in vitro and in vivo assessments of anticancer activity, which is promising for various biomedical purposes.

Potential Therapeutic Targets of Epigallocatechin Gallate (EGCG), the Most Abundant Catechin in Green Tea, and Its Role in the Therapy of Various Types of Cancer

Epigallocatechin-3-gallate (EGCG), an active compound of green tea and its role in diseases cure and prevention has been proven. Its role in diseases management can be attributed to its antioxidant and anti-inflammatory properties. The anti-cancer role of this green tea compound has been confirmed in various types of cancer and is still being under explored. EGCG has been proven to possess a chemopreventive effect through inhibition of carcinogenesis process such as initiation, promotion, and progression. In addition, this catechin has proven its role in cancer management through modulating various cell signaling pathways such as regulating proliferation, apoptosis, angiogenesis and killing of various types of cancer cells. The additive or synergistic effect of epigallocatechin with chemopreventive agents has been verified as it reduces the toxicities and enhances the anti-cancerous effects. Despite its effectiveness and safety, the implications of EGCG in cancer prevention is certainly still discussed due to a poor bioavailability. Several studies have shown the ability to overcome poor bioavailability through nanotechnology-based strategies such as encapsulation, liposome, micelles, nanoparticles and various other formulation. In this review, we encapsulate therapeutic implication of EGCG in cancer management and the mechanisms of action are discussed with an emphasis on human clinical trials.

Genoprotective activities of plant natural substances in cancer and chemopreventive strategies in the context of 3P medicine

Severe durable changes may occur to the DNA structure caused by exogenous and endogenous risk factors initiating the process of carcinogenesis. By evidence, a large portion of malignancies have been demonstrated as being preventable. Moreover, the targeted prevention of cancer onset is possible, due to unique properties of plant bioactive compounds. Although genoprotective effects of phytochemicals have been well documented, there is an evident lack of articles which would systematically present the spectrum of anticancer effects by phytochemicals, plant extracts, and plant-derived diet applicable to stratified patient groups at the level of targeted primary (cancer development) and secondary (cancer progression and metastatic disease) prevention. Consequently, clinical implementation of knowledge accumulated in the area is still highly restricted. To stimulate coherent co-development of the dedicated plant bioactive compound investigation on one hand and comprehensive cancer preventive strategies on the other hand, the current paper highlights and deeply analyses relevant evidence available in the area. Key molecular mechanisms are presented to detail genoprotective and anticancer activities of plants and phytochemicals. Clinical implementation is discussed. Based on the presented evidence, advanced chemopreventive strategies in the context of 3P medicine are considered.

Evaluation radioprotective effect of curcumin conjugated albumin nanoparticles

In this research, curcumin (CUR) conjugated albumin based nanoparticles (BSA-CUR) were designed for improvement and evaluation radioprotective effect of CUR. In this way, we have prepared BSA-CUR by covalently binding the CUR with BSA. Next, this synthesized prodrug was evaluated for physical and chemical properties by Fourier-transform infrared (FTIR), Dynamic light scattering (DLS), Transmission electron microscopy (TEM), Ultraviolet-visible (UV/Vis), and Differential scanning calorimetry (DSC) analysis. Furthermore, the chemical stability of designed prodrug was appraised. The result shows that the size of nanoparticles is 174.4 nm with a polydispersity index (PdI) of 0.191. The nanoparticles have a high loading capacity and show sustained release behavior. Loading of CUR to BSA not only could increase the chemical stability of CUR, but also could improve radioprotection efficacy of it's against X-Ray irradiation. The HHF-2 cells show 107% viability in the presence of BSA-CUR at a concentration of 50 µg/mL, whereas non-treated cells show 46% viability, under X-Ray irradiation. Also in vivo study results show that, four out of five mice have died when the mice irradiated by X-Ray and no received any treatment. Although, for a group that treated with BSA-CUR and also irradiated by X-Ray, median survival and survival rate was higher than CUR treated and control mice, and only two out of five mice have died. The result of this study proved that BSA-CUR can be used as a proficient vehicle for improving the potential radioprotective effect of CUR.

Dietary flavonoids: Nano delivery and nanoparticles for cancer therapy

Application of nanotechnologies to cancer therapy might increase solubility and/or bioavailability of bioactive compounds of natural or synthetic origin and offers other potential benefits in cancer therapy, including selective targeting. In the present review we aim to evaluate in vivo studies on the anticancer activity of nanoparticles (NPs) obtained from food-derived flavonoids. From a systematic search a total of 60 studies were identified. Most of the studies involved the flavanol epigallocatechin-3-O-gallate and the flavonol quercetin, in both delivery and co-delivery (with anti-cancer drugs) systems. Moreover, some studies investigated the effects of other flavonoids, such as anthocyanins aglycones anthocyanidins, flavanones, flavones and isoflavonoids. NPs inhibited tumor growth in both xenograft and chemical-induced animal models of cancerogenesis. Encapsulation improved bioavailability and/or reduced toxicity of both flavonoids and/or co-delivered drugs, such as doxorubicin, docetaxel, paclitaxel, honokiol and vincristine. Moreover, flavonoids have been successfully applied in molecular targeted nanosystems. Selectivity for cancer cells involves pH- and/or reactive oxygen species-mediated mechanisms. Furthermore, flavonoids are good candidates as drug delivery for anticancer drugs in green synthesis systems. In conclusion, although human studies are needed, NPs obtained from food-derived flavonoids have promising anticancer effects in vivo.

BSA Nanoparticles Modified with N-Acetylcysteine for Improving the Stability and Mucoadhesion of Curcumin in the Gastrointestinal Tract

A major obstacle to the clinical use of curcumin (CUR) is its reduced bioavailability because of the drug's hydrophobic nature, low intestinal absorption, and rapid metabolism. In this study, a novel oral drug delivery system was constructed for improving the stability and enhancing mucoadhesion of CUR in the gastrointestinal (GI) tract. First, CUR was encapsulated in the bovine serum albumin nanoparticles (CUR-BSA-NPs). Then, N-acetyl cysteine (NAC)-modified CUR-BSA-NPs (CUR-NBSA-NPs) were obtained. The average particle size and zeta potential of CUR-NBSA-NPs were 251.6 nm and -30.66 mV, respectively; encapsulation efficiency and drug loading were 85.79 and 10.9%, respectively. CUR-NBSA-NPs exhibited a sustained release property and prominently enhanced stability in simulated GI conditions. Additionally, enhanced mucoadhesion of CUR-NBSA-NPs was also observed. An MTT study showed that the CUR-NBSA-NPs were safe for oral administration. Overall, NAC-modified BSA-NPs may potentially serve as an oral vehicle for improving CUR stability in the GI tract and enhancing mucoadhesion.

Flavonoids nanoparticles in cancer: Treatment, prevention and clinical prospects

The conventional therapies for cancer have a major concern of poor accessibility to tumor tissues. Furthermore, the requirement of higher doses and non-selective nature of therapeutic are associated with a range of adverse drug reactions (ADRs). However, flavonoids are documented to be effective against various types of cancer, but they are not evaluated for their safety profile and tumor site-specific action. Low solubility, rapid metabolism and poor absorption of dietary flavonoids in gastrointestinal tract hinder their pharmacological potential. Some studies have also suggested that flavonoids may act as pro-oxidant in some cases and may interact with other therapeutic agents, especially through biotransformation. Nanocarriers can alter pharmacokinetics and pharmacodynamic profile of incorporating drug. Moreover, nanocarriers are designed for targeted drug delivery, improving the bioavailability of poorly water-soluble drugs, delivery of macromolecules to site of action within the cell, combining therapeutic agents with imaging techniques which may visualize the site of drug delivery and co-delivery of two or more drugs. Combining two or more anti-cancer agents can reduce ADRs and nanotechnology played a pivotal role in this regard. In vitro and in vivo studies have shown the potential of flavonoids nano-formulations, especially quercetin, naringenin, apigenin, catechins and fisetin in the prevention and treatment of several types of cancer. Similarly, clinical trials have been conducted using flavonoids alone or in combination, however, the nano-formulations effect still needs to be elucidated. This review focuses on the impact of flavonoids nano-formulations on the improvement of their bioavailability, therapeutic and safety profile and will open new insights in the field of drug discovery for cancer therapeutics.

Delivery of synergistic polyphenol combinations using biopolymer-based systems: Advances in physicochemical properties, stability and bioavailability

When consumed at sufficiently high levels, polyphenols may provide health benefits, which is linked to their antidiabetic, antiinflamatory, antimicrobial, antioxidant, antitumor, and hypolipidemic properties. Moreover, certain polyphenol combinations exhibit synergistic effects when delivered together - the combined polyphenols have a higher biological activity than the sum of the individual ones. However, the commercial application of polyphenols as nutraceuticals is currently limited because of their poor solubility characteristics; instability when exposed to light, heat, and alkaline conditions; and, low and inconsistent oral bioavailability. Colloidal delivery systems are being developed to overcome these challenges. In this article, we review the design, fabrication, and utilization of food-grade biopolymer-based delivery systems for the encapsulation of one or more polyphenols. In particular, we focus on the creation of delivery systems constructed from edible proteins and polysaccharides. The optimization of biopolymer-based delivery systems may lead to the development of innovative polyphenol-enriched functional foods that can improve human health and wellbeing.

Encapsulation of epigallocatechin-3-gallate into albumin nanoparticles improves pharmacokinetic and bioavailability in rat model

In the present study, we fabricated epigallocatechin-3-gallate (EGCG) loaded albumin nanoparticles (Alb-NP-EGCG) to enhance bioavailability and improve pharmacokinetic parameters of EGCG. The physicochemical properties of the Alb-NP-EGCG were studied using scanning electron microscopy, differential scanning calorimetry, powder X-ray diffraction and in vitro release studies. Characterization of Alb-NP-EGCG indicated the formation of spherical nanoparticles with no drug and excipient interaction. Alb-NP-EGCG showed a high drug loading capacity of 92%. Further, in vitro study showed a sustained release of EGCG from Alb-NP-EGCG over a period of 48 h. Mathematical modeling and release kinetics indicated that the Alb-NP-EGCG followed zero order kinetic and EGCG was released via fickian diffusion method. In vivo bioavailability and distribution of Alb-NP-EGCG showed an enhanced plasma concentration of EGCG with 1.5 fold increase along with prolonged T 1/2 of 15.6 h in the system when compared with the free EGCG. All this study demonstrated the fabrication of EGCG loaded albumin nanoparticles which favored the slow and sustained release of EGCG with improved pharmacokinetics and bioavailability thereby prolonging the action of EGCG. Additional acute and sub-acute toxicity test of the Alb-NP-EGCG demonstrated the safety of the Alb-NP-EGCG. Therefore, the Alb-NP-EGCG could be a promising drug delivery system for EGCG.

Modification of Serum Albumin by High Conversion of Carboxyl to Amino Groups Creates a Potent Inhibitor of Amyloid β-Protein Fibrillogenesis

Fibrillogenesis of amyloid β-protein (Aβ) has been thought to be implicated in the progression of Alzheimer's disease (AD). Therefore, development of high-efficiency inhibitors is one of the strategies for the prevention and treatment of AD. Serum albumin has been found to capture Aβ monomers through its hydrophobic groove and suppress amyloid formation, but the inhibition efficiency is limited. Inspired by the strong inhibition potency of a basic protein, human lysozyme, we have herein proposed to develop a basified serum albumin by converting carboxyl groups into amino groups with ethylenediamine conjugated on the protein surface. The idea was verified with both bovine and human serum albumins (BSA/HSA). Four basified BSA (BSA-B) preparations with amino modification degrees (MDs) from 8.0 to 41.5 were first synthesized. Extensive biophysical and biological analyses revealed that the inhibition potency significantly increased with increasing amino MD. BSA-B of the highest MD (41.5), BSA-B4, which had an isoelectric point of 9.7, presented strong inhibition on Aβ₄₂ fibrillation at a concentration as low as 0.5 μM, at which it functioned similarly with 25 μM native BSA to impede 25 μM Aβ fibrillation. Cell viability assays also confirmed that the detoxification of 5 μM BSA-B4 was superior over 25 μM native BSA by increasing cell viability from 60.6% to 96.0%. Fluorescence quenching study unveiled the decrease of the binding affinity between Aβ₄₂ and the hydrophobic pocket region of BSA-B4, while quartz crystal microbalance experiments demonstrated that the binding constant of BSA-B4 to Aβ₄₂ increased nearly 5 times. Therefore, the increase of electrostatic interactions between BSA-B4 and Aβ₄₂ was the main reason for its high potency. Hence, aminated BSA achieved a conversion of binding way to Aβ from a mainly single-site hydrophobic binding to multiregional electrostatic interactions. Similar results were obtained with basified HSA preparations on inhibiting the amyloid formation and cytotoxicity. This work has thus provided new insights into the development of more efficient protein-based inhibitors against Aβ fibrillogenesis.

Graphdiyne Nanoparticles with High Free Radical Scavenging Activity for Radiation Protection

Numerous carbon networks materials comprised of benzene moieties, such as graphene and fullerene, have held great fascination for radioprotection because of their acknowledged good biocompatibility and strong free radical scavenging activity derived from their delocalized π-conjugated structure. Recently, graphdiyne, a new emerging carbon network material consisting of a unique chemical structure of benzene and acetylenic moieties, has gradually attracted attention in many research fields. Encouraged by its unique structure with strong conjugated π-system and highly reactive diacetylenic linkages, graphdiyne might have free radical activity and can thus be used as a radioprotector, which has not been investigated so far. Herein, for the first time, we synthesized bovine serum albumin (BSA)-modified graphdiyne nanoparticles (graphdiyne-BSA NPs) to evaluate their free radical scavenging ability and investigate their application for radioprotection both in cell and animal models. In vitro studies indicated that the graphdiyne-BSA NPs could effectively eliminate the free-radicals, decrease radiation-induced DNA damage in cells, and improve the viability of cells under ionizing radiation. In vivo experiments showed that the graphdiyne-BSA NPs could protect the bone marrow DNA of mice from radiation-induced damage and make the superoxide dismutase (SOD) and malondialdehyde (MDA) (two kinds of vital indicators of radiation-induced injury) recover back to normal levels. Furthermore, the good biocompatibility and negligible systemically toxicity responses of the graphdiyne-BSA NPs to mice were verified. All these results manifest the good biosafety and radioprotection activity of graphdiyne-BSA NPs to normal tissues. Therefore, our studies not only provide a new radiation protection platform based on graphdiyne for protecting normal tissues from radiation-caused injury but also provide a promising direction for the application of graphdiyne in the biomedicine field.

Fabrication of BSA-Pinus koraiensis polyphenol-chitosan nanoparticles and their release characteristics under in vitro simulated gastrointestinal digestion

BSA and chitosan were used to prepare nanoparticles of polyphenols from the pine cones of Pinus koraiensis (PKP-NPs).

Application of Multifunctional Nanomaterials in Radioprotection of Healthy Tissues

Radiotherapy has been extensively used in clinic for malignant tumors treatment. However, a severe challenge of it is that the ionizing radiation needed to kill tumors inevitably causes damage to surrounding normal tissues. Although some of the molecular radioprotective drugs, such as amifostine, have been used as clinical adjuvants to radio-protect healthy tissues, their shortcomings such as short systemic circulation time and fast biological clearing from the body largely hinder the sustained bioactivity. Recently, with the rapid development of nanotechnology in the biological field, the multifunctional nanomaterials not only establish powerful drug delivery systems to improve the molecular radioprotective drugs' biological availability, but also open a new route to develop neozoic radioprotective agents because some nanoparticles possess intrinsic radioprotective abilities. Therefore, considering these overwhelming superiorities, this review systematically summarizes the advances in healthy tissue radioprotection applications of multifunctional nanomaterials. Furthermore, this review also points out a perspective of nanomaterial designs for radioprotection applications and discusses the challenges and future outlooks of the nanomaterial-mediated radioprotection.

Bioavailability of Tea Catechins and Its Improvement

Many in vitro studies have shown that tea catechins had vevarious health beneficial effects. However, inconsistent results between in vitro and in vivo studies or between laboratory tests and epidemical studies are observed. Low bioavailability of tea catechins was an important factor leading to these inconsistencies. Research advances in bioavailability studies involving absorption and metabolic biotransformation of tea catechins were reviewed in the present paper. Related techniques for improving their bioavailability such as nanostructure-based drug delivery system, molecular modification, and co-administration of catechins with other bioactives were also discussed.

Application of microencapsulation for the safe delivery of green tea polyphenols in food systems: Review and recent advances

Green tea has been associated with the prevention and reduction of a wide range of severe health conditions such as cancer, immune, and cardiovascular diseases. The health benefits associated with green tea consumption have been predominantly attributed to green tea polyphenols. The functional properties of green tea polyphenols are mainly anti-oxidative, antimutagenic, anticarcinogenic, anti-microbial, etc. These excellent properties have recently gained considerable attention in the food industry. However, their application is limited by their sensitivity to factors like temperature, light, pH, oxygen, etc. More, studies have reported the occurrence of unpleasant taste and color transfer during food processing. Lastly, the production of functional food requires to maintain the stability, bioactivity, and bioavailability of the active compounds. To tackle these obstacles, technological approaches like microencapsulation have been developed and applied for the formulation of green tea-enriched food products. The present review discusses the novelty in microencapsulation techniques for the safe delivery of green tea polyphenols in food matrices. After a literature on the green tea polyphenols composition, and their health attributes, the encapsulation methods and the coating materials are presented. The application of green tea encapsulates in food matrices as well as their effect on food functional and sensory properties are also discussed.

β-Lactoglobulin–chlorogenic acid conjugate-based nanoparticles for delivery of (−)-epigallocatechin-3-gallate

The release of EGCG was controlled by BLG–CA conjugate.