Development of Enteromorpha prolifera polysaccharide-based nanoparticles for delivery of curcumin to cancer cells

Preparation, stability, and antibacterial activity of carboxymethylated Anemarrhena asphodeloides polysaccharide-chitosan nanoparticles loaded curcumin

In present study, polysaccharide polyelectrolyte nanoparticles (CMAAP-CS NPs) were constructed by mixing carboxymethylated Anemarrhena asphodeloides polysaccharide (CMAAP) and chitosan (CS). CMAAP-CS NPs were applied as carrier to improve the bioavailability and stability of curcumin (Cur). The average particle size of CMAAP-CS NPs was 216.60 ± 4.21 nm and the entrapment efficiency of Cur reached 82.50 ± 2.09 %. The simulated digestion experiments in vitro confirmed that the bioavailability of Cur loaded in CMAAP-CS NPs was 59.84 ± 0.03 % after saliva, gastric and intestinal digestion, which was obvious higher than 21.57 ± 0.07 % of free Cur under the same conditions. The results of stability testing revealed that CMAAP-CS NPs could markedly reduce the degradation of Cur against storage, heating, UV light treatment, and neutral pH. This study provided promising polyelectrolyte complex loaded hydrophobic nutrients in medicine industry.

Structural characterization and anti-inflammatory effects of Enteromorpha prolifera polysaccharide-Fe/Zn complexes

The structure of polysaccharide has a great influence on its biological functions, and the chelation with metal ions is an effective way to change polysaccharide structural configuration. Herein, the structure of Enteromorpha prolifera polysaccharide (EP)-Fe/Zn complexes were characterized and the results showed that the iron (III) existed in form of β-FeOOH in EP-Fe (III) complex and the zinc (II) existed in form of C-O-Zn in EP-Zn (II) complex. Besides, the chelation with iron (III) or zinc (II) completely changed the apparent forms, and improved the thermal stability of EP. Furthermore, the anti-inflammatory activities of EP, EP-Fe and EP-Zn were proved by a lipopolysaccharide (LPS)-induced RAW264.7 macrophages model. The results showed that EP, EP-Fe (III) and EP-Zn (II) could decrease the mitochondrial membrane potential and the secretion of NO and cytokines induced by LPS. One of the anti-inflammatory mechanisms of EP, EP-Fe (III) and EP-Zn (II) was that they could inhibit mitogen-activated protein kinase (MAPK) signaling pathway via increasing its inhibitor content in cells. Collectively, the research suggested that the chelation with iron (III) or zinc (II) could change the structure and improve the anti-inflammatory activities of EP.

Antitumor effects of polysaccharides from medicinal lower plants: A review

Cancer is one of the leading causes of death worldwide, yet the drugs currently approved for cancer treatment are associated with significant side effects, making it urgent to develop alternative drugs with low side effects. Polysaccharides are natural polymers with ketone or aldehyde groups, which are widely found in plants and have various biological activities such as immunomodulation, antitumor and hypolipidemic. The lower plants have attracted much attention for their outstanding anticancer effects, and many studies have shown that medicinal lower plant polysaccharides (MLPPs) have antitumor activity against various cancers and are promising alternatives with potential development in the food and pharmaceutical fields. Therefore, this review describes the structure and mechanism of action of MLPPs with antitumor activity. In addition, the application of MLPPs in cancer treatment is discussed, and the future development of MLPPs is explored.

Immunomodulatory, Antioxidant, Anticancer, and Pharmacokinetic Activity of Ulvan, a Seaweed-Derived Sulfated Polysaccharide: An Updated Comprehensive Review

Cancer is one of the most worldwide spread diseases and causes maximum death. Treatment of cancer depends on the host immune system and the type of drugs. The inefficiency of conventional cancer treatments as a result of drug resistance, nontargeted delivery, and chemotherapy-related negative side effects has caused bioactive phytochemicals to come into focus. As a result, recent years have seen an increase in research into screening and identifying natural compounds with anticancer properties. Recent studies on the isolation and use of polysaccharides derived from various marine algal species have revealed a variety of biological activities, including antioxidant and anticancer properties. Ulvan is a polysaccharide derived from various green seaweeds of the Ulva species in the family Ulvaceae. It has been demonstrated to have potent anticancer and anti-inflammatory properties through the modulation of antioxidants. It is vital to understand the mechanisms underlying the biotherapeutic activities of Ulvan in cancer and its role in immunomodulation. In this context, we reviewed the anticancer effects of ulvan based on its apoptotic effects and immunomodulatory activity. Additionally, we also focused on its pharmacokinetic studies in this review. Ulvan is the most conceivable candidate for use as a cancer therapeutic agent and could be used to boost immunity. Moreover, it may be established as an anticancer drug once its mechanisms of action are understood. Due to its high food and nutritive values, it can be used as a possible dietary supplement for cancer patients in the near future. This review may provide fresh perspectives on the potential novel role of ulvan, reveal a brand-new cancer-prevention strategy, and improve human health.

Nanoparticles loaded with pharmacologically active plant-derived natural products: Biomedical applications and toxicity

Pharmacologically active natural products have played a significant role in the history of drug development. They have acted as sources of therapeutic drugs for various diseases such as cancer and infectious diseases. However, most natural products suffer from poor water solubility and low bioavailability, limiting their clinical applications. The rapid development of nanotechnology has opened up new directions for applying natural products and numerous studies have explored the biomedical applications of nanomaterials loaded with natural products. This review covers the recent research on applying plant-derived natural products (PDNPs) nanomaterials, including nanomedicines loaded with flavonoids, non-flavonoid polyphenols, alkaloids, and quinones, especially their use in treating various diseases. Furthermore, some drugs derived from natural products can be toxic to the body, so the toxicity of them is discussed. This comprehensive review includes fundamental discoveries and exploratory advances in natural product-loaded nanomaterials that may be helpful for future clinical development.

The Study of Enteromorpha-Based Reinforcing-Type Flame Retardant on Flame Retardancy and Smoke Suppression of EPDM

Enteromorpha, as a waste from marine pollution, brings great pressure to environmental governance every year, especially for China. Under the premise of a shortage of industrial materials, taking appropriate measures can turn waste into wealth, which will benefit us a lot. In this work, a bio-based reinforcing-type flame retardant based on Enteromorpha is designed. The designed Enteromorpha-based flame retardant system (AEG) mainly focuses on the reinforcing and flame retardant effects on ethylene-propylene-diene tripolymer (EPDM). For the AEG system, ammonium polyphosphate (APP) serves as both the acid source and the gas source; the simple hybrid material (GN) produced by loading graphene (GE) and Enteromorpha (EN) using tannic acid (TA) as a regulator serves as an acid source and a carbonizing source. The results show that when 40 phr AEG is added, the LOI of EPDM/AEG40 reaches 32.5% and the UL-94 reaches the V-0 level. The PHRR and THR values of EPDM/AEG40 are 325.9 kW/m² and 117.6 MJ/m², respectively, with decrements of 67.3% and 29.7%, respectively, compared with the results of neat EPDM composite. Especially, the TSP and TSR values of EPDM/AEG40 are reduced from 15.2 m² of neat EPDM to 9.9 m² with a decrement of 34.9% and reduced from 1715.2 m²/m² of neat EPDM to 1124.5 m²/m² with a decrement of 34.4%, indicating that AEG is effective in flame retardancy and smoke suppression. Meanwhile, the tensile strength and tear strength of EPDM/AEG composites are much higher than neat EPDM, therefore, with the future development of innovate reinforcing-type flame-retardant Enteromorpha, the application of Enteromorpha in the polymer flame-retardant field will surely usher in bright development.

Multifunctional nanoparticles based on marine polysaccharides for apremilast delivery to inflammatory macrophages: Preparation, targeting ability, and uptake mechanism

Hydrophobic drug encapsulation inside targeted nanoparticles can enhance accumulation in inflamed sites, limit toxicity to healthy tissue, and improve pharmacokinetics compared to free drug dosing. This study reports a functionalized marine polysaccharide nanoparticle with a controlled release, targeting abilities, and in-situ imaging properties. Carbon dots functionalized Enteromorpha polysaccharide/Mannose/Methionine functionalized Chitosan (CDs.EP/Man/Meth.Cs) NPs could deliver apremilast to inflammatory macrophages and Caco-2 intestinal cells as an in vitro model for application in oral drug delivery to cure IBD. The nanoparticles were simply a polyelectrolyte complex between cationic functionalized chitosan and anionic polysaccharide of Enteromorpha prolifera. Functionalized polysaccharides and the prepared NPs were well characterized. The functionalized nanoparticles could overcome the limitation of poor drug bioavailability and showed a high loading capacity of (45 %) with a controlled release of about (74.5 %). Confocal laser scanning imaging showed higher cellular uptake of the modified nanoparticles than that of the unmodified nanoparticles in LPS-activated RAW 264.7 macrophages and Caco-2 cells. The effect of functionalization on the cellular uptake targetability was assessed using spectrofluorometric measurements after mannose competition. Anti-inflammatory activity of apremilast-loaded NPs is more elevated than the free drug. These results suggest the feasibility of using functionalized EP/Cs nanoparticles in IBD oral drug delivery.

Enteromorpha cellulose micro-nanofibrils/poly(vinyl alcohol) based composite films with excellent hydrophilic, mechanical properties and improved thermal stability

This study presents the preparation of cellulose micro-nanofibrils (CMNFs) from Enteromorpha (EP) and the application in PVA/acetylated distarch phosphate (ADSP)/CMNFs composite films. The Micro-nano scale, hydrophilicity, and strong hydrogen bond characteristics of CMNFs prepared form EP by acid hydrolysis were confirmed through the granular statistics, XRD analysis and chemical structure analysis. With the addition of CMNFs, the ultimate tensile strength and elongation at break of composite films are increased by 42.4 % and 90.3 %. An original Weibull statistical analysis shows the impact of CMNFs' added amount on strength distribution and ultimate stress. SEM and polarizing microscope images show the CMNFs' dispersion state in that films is optimal, when their addition was to be 2 %-3 % of total dry weight of PVA/ADSP matrix， which is consistent with the results of Weibull modulus analysis. The main thermal weight-loss process of the composite film is divided into four stages, CMNFs can significantly increase the thermostability at 280 °C to 400 °C. The experiment of water contact angle and water vapor transmission rate of the composite films confirmed that CMNFs can improve films' hydrophilicity. This study provides basis for the preparation of hydrophilic CMNFs and mechanism of modification study PVA-based composites.

Fabrication and characterization of octenyl succinic anhydride modified pullulan micelles for encapsulating curcumin

BACKGROUND

Curcumin has become increasingly popular in functional foods and beverages field as a result of its high biological activity. Nevertheless, the application of curcumin is usually limited by its poor water solubility, low absorption, rapid metabolism and instability. Accordingly, the development of an appropriate wall material is crucial for its effective use. In the present study, curcumin-octenyl succinic anhydride modified pullulan (Cur-OSAP) micelles were successfully prepared by an anti-solvent co-precipitation method.

RESULTS

Octenyl succinic anhydride modified pullulan (OSAP) micelles exhibited the highest encapsulation efficiency (57.31%) and loading capacity (5.73%) of curcumin when the mass ratio of OSAP to curcumin was 10:1 and the degree of substitution of OSAP was 0.0469, at which point Cur-OSAP micelles formed via hydrogen binding and hydrophobic interactions, as confirmed by Fourier transform infrared and fluorescence techniques. The transmission electron microscopy results showed that the Cur-OSAP micelles were roughly spherical in shape with diameters in the approximate range 30-60 nm.

CONCLUSION

The encapsulation of OSAP greatly improved photostability and sustained release properties of curcumin in Cur-OSAP micelles. These findings suggest that OSAP can be used as a carrier to encapsulate and protect hydrophobic food ingredients. © 2021 Society of Chemical Industry.

Synthesis, characterization and application of chitosan-N-(4-hydroxyphenyl)-methacrylamide derivative as a drug and gene carrier

The aim of this study was to develop a green method to fabricate a novel CS modified N-(4-hydroxyphenyl)- methacrylamide conjugate (CSNHMA) and to evaluate its biomedical potential. CSNHMA has been prepared by a simple method via aza Michael addition reaction between CS and N- (4-hydroxyphenyl)-methacrylamide (NHMA) in ethanol. Its structural and morphological properties were characterized by various analysis techniques. The obtained results confirmed that a highly porous network structure of CSNHMA was successfully synthesized via aza Michael addition reaction. Consequently, it was analyzed as a drug and gene carrier. CSNHMA/pGL3 showed an enhanced buffering capacity due to the presence of NHMA moiety leading to higher transfection efficiency in all cancer cells (A549, HeLa and HepG2) as compared to native CS and Lipofectamine®. Therefore, these findings clearly support the possibility of using CSNHMA as a good transfection agent. For in vitro drug release study, we prepared CSNHMA nanoparticles (NPs) and curcumin loaded CSNHMA NPs of size <230 nm respectively via the non-toxic ionic gelation route and the encapsulation efficiency of drug was found to be 77.03%. In vitro drug release studies demonstrated a faster and sustained release of curcumin loaded CSNHMA NPs at pH 5.0 compared to physiological pH.

Extraction Techniques, Biological Activities and Health Benefits of Marine Algae Enteromorpha prolifera Polysaccharide

There is increasing interest in the use of marine algae as functional food additives for improving human health. Enteromorpha (Ulva) prolifera (E. prolifera) is a seaweed green alga (Chlorophyta) that contains many bioactive compounds, of which polysaccharide is the main component. With the advancement of technology in the methods of extraction and analysis, recent studies in in vitro and animals model showed that polysaccharides derived from E. prolifera exert various biological activities, such as gut microbiota modulation, immunomodulation, antioxidant, antidiabetic, antimicrobial, and hypolipidemic. Research evidence has shown that methods of extraction and molecular modification, such as degradation, carboxymethylation, and sulfonation could alter the biological activities of polysaccharides. Therefore, in this review, we discussed the different extraction techniques, structural-activity relationship, and health benefits of sulfated polysaccharides derived from E. prolifera, and suggested future research avenues. This review helps to advance the extraction techniques and promote the application of marine algae polysaccharides as functional food and therapeutic agent.

Modifications of polysaccharide-based biomaterials under structure-property relationship for biomedical applications

Polysaccharides are well accepted biomaterials that have attracted considerable attention. Compared with other materials under research, polysaccharides show unique advantages: they are available in nature and are normally easily acquired, those acquired from nature show favorable immunogenicity, and are biodegradable and bioavailable. The bioactivity and possible applications are based on their chemical structure; however, naturally acquired polysaccharides sometimes have unwanted flaws that limit further applications. For this reason, carefully summarizing the possible modifications of polysaccharides to improve them is crucial. Structural modifications can not only provide polysaccharides with additional functional groups but also change their physicochemical properties. This review based on the structure-property relation summarizes the common chemical modifications of polysaccharides, the related bioactivity changes, possible functionalization methods, and major possible biomedical applications based on modified polysaccharides.

Photocuring Hyaluronic Acid/Silk Fibroin Hydrogel Containing Curcumin Loaded CHITOSAN Nanoparticles for the Treatment of MG-63 Cells and ME3T3-E1 Cells

After an osteosarcoma excision, recurrence and bone defects are significant challenges for clinicians. In this study, the curcumin (Cur) loaded chitosan (CS) nanoparticles (CCNP) encapsulated silk fibroin (SF)/hyaluronic acid esterified by methacrylate (HAMA) (CCNPs-SF/HAMA) hydrogel for the osteosarcoma therapy and bone regeneration was developed by photocuring and ethanol treatment. The micro or nanofibers networks were observed in the CCNPs-SF/HAMA hydrogel. The FTIR results demonstrated that alcohol vapor treatment caused an increase in β-sheets of SF, resulting in the high compression stress and Young’s modulus of CCNPs-SF/HAMA hydrogel. According to the water uptake analysis, SF caused a slight decrease in water uptake of CCNPs-SF/HAMA hydrogel while CCNPs could enhance the water uptake of it. The swelling kinetic results showed that both the CCNPs and the SF increased the swelling ratio of CCNPs-SF/HAMA hydrogel. The accumulative release profile of CCNPs-SF/HAMA hydrogel showed that the release of Cur from CCNPs-SF/HAMA hydrogel was accelerated when pH value was decreased from 7.4 to 5.5. Besides, compared with CCNPs, the CCNPs-SF/HAMA hydrogel had a more sustainable drug release, which was beneficial for the long-term treatment of osteosarcoma. In vitro assay results indicated that CCNPs-SF/HAMA hydrogel with equivalent Cur concentration of 150 μg/mL possessed both the effect of anti-cancer and promoting the proliferation of osteoblasts. These results suggest that CCNPs-SF/HAMA hydrogel with superior physical properties and the bifunctional osteosarcoma therapy and bone repair may be an excellent candidate for local cancer therapy and bone regeneration.

Recent updates in the polysaccharides-based Nano-biocarriers for drugs delivery and its application in diseases treatment: A review

With people's increasing awareness of diseases treatment, the researchers began to focus on drug delivery to the exact site of action at the optimal rate. Some researchers have proved that many nanostructures loaded with drugs are significantly better than conventional nanostructures. However, the materials from which the nanostructure determines its performance. To use it as a pharmaceutical ingredient, it must meet strict safety regulatory standards worldwide. Therefore, people's attention has paid to easily available natural substances. As far as we know, bioactive polysaccharides are excellent candidates for realizing these purposes. To be precise, due to the natural availability of polysaccharides, it has been widely used in the research of Nano-biocarriers loaded with drugs. Based on the above analysis, the nanomaterials developed through the laboratory have great potential for upgrading to market products. Therefore, it is of great significance to review the latest progress of polysaccharide-based Nano-biocarriers in drug delivery and their application in diseases treatment. In this work, we focused on the preparation of polysaccharides-based Nano-biocarriers, commonly used polysaccharides for preparing Nano-biocarriers, and drugs loaded on polysaccharides-based Nano-biocarriers to treat diseases. Shortly, polysaccharide-based Nano-biocarriers will be increasingly used in drug delivery and treatment of diseases.

A Cost-Effective Nano-Sized Curcumin Delivery System with High Drug Loading Capacity Prepared via Flash Nanoprecipitation

Flash nanoprecipitation (FNP) is an efficient technique for encapsulating drugs in particulate carriers assembled by amphiphilic polymers. In this study, a novel nanoparticular system of a model drug curcumin (CUR) based on FNP technique was developed by using cheap and commercially available amphiphilic poly(vinyl pyrrolidone) (PVP) as stabilizer and natural polymer chitosan (CS) as trapping agent. Using this strategy, high encapsulation efficiency (EE > 95%) and drug loading capacity (DLC > 40%) of CUR were achieved. The resulting CUR-loaded nanoparticles (NPs) showed a long-term stability (at least 2 months) and pH-responsive release behavior. This work offers a new strategy to prepare cost-effective drug-loaded NPs with high drug loading capacity and opens a unique opportunity for industrial scale-up.

Chitosan-based nanocarriers for encapsulation and delivery of curcumin: A review

To overcome the poor aqueous solubility and bioavailability of curcumin, emphasize its functional features, and broaden its applications in the food and pharmaceutical industries, many nanoscale systems have been widely applied for its encapsulation and delivery. Over many decades, chitosan as a natural biopolymer has been extensively studied due to its polycationic nature, biodegradability, biocompatibility, non-toxicity, and non-allergenic. Various chitosan-based nanocarriers with unique properties for curcumin delivery, including but not limited to, self-assembled nanoparticles, nanocomposites, nanoemulsions, nanotubes, and nanofibers, have been designed. This review focuses on the most-recently reported fabrication techniques of different types of chitosan-based nanocarriers. The functionalities of chitosan in each formulation which determine the physicochemical properties such as surface charge, morphology, encapsulation driving force, and release profile, were discussed in detail. Moreover, the current pharmaceutical applications of curcumin-loaded chitosan nanoparticles were elaborated. The role of chitosan in facilitating the delivery of curcumin and improving the therapeutic effects on many chronic diseases, including cancer, bacterial infection, wound healing, Alzheimer's diseases, inflammatory bowel disease, and hepatitis C virus, were illustrated. Particularly, the recently discovered mechanisms of action of curcumin-loaded chitosan nanoparticles against the abovementioned diseases were highlighted.

Novel Therapeutic Delivery of Nanocurcumin in Central Nervous System Related Disorders

Nutraceuticals represent complementary or alternative beneficial products to the expensive and high-tech therapeutic tools in modern medicine. Nowadays, their medical or health benefits in preventing or treating different types of diseases is widely accepted, due to fewer side effects than synthetic drugs, improved bioavailability and long half-life. Among herbal and natural compounds, curcumin is a very attractive herbal supplement considering its multipurpose properties. The potential effects of curcumin on glia cells and its therapeutic and protective properties in central nervous system (CNS)-related disorders is relevant. However, curcumin is unstable and easily degraded or metabolized into other forms posing limits to its clinical development. This is particularly important in brain pathologies determined blood brain barrier (BBB) obstacle. To enhance the stability and bioavailability of curcumin, many studies focused on the design and development of curcumin nanodelivery systems (nanoparticles, micelles, dendrimers, and diverse nanocarriers). These nanoconstructs can increase curcumin stability, solubility, in vivo uptake, bioactivity and safety. Recently, several studies have reported on a curcumin exosome-based delivery system, showing great therapeutical potential. The present work aims to review the current available data in improving bioactivity of curcumin in treatment or prevention of neurological disorders.

Immunomodulatory Effects of a Low-Molecular Weight Polysaccharide from Enteromorpha prolifera on RAW 264.7 Macrophages and Cyclophosphamide- Induced Immunosuppression Mouse Models

The water-soluble polysaccharide EP2, from Enteromorpha prolifera, belongs to the group of polysaccharides known as glucuronoxylorhamnan, which mainly contains glucuronic acid (GlcA), xylose (Xyl), and rhamnose (Rha). The aim of this study was to detect the immunomodulatory effects of EP2 on RAW 264.7 macrophages and cyclophosphamide (CYP)-induced immunosuppression mouse models. The cells were treated with EP2 for different time periods (0, 0.5, 1, 3, and 6 h). The results showed that EP2 promoted nitric oxide production and up-regulated the expression of pro-inflammatory cytokines, such as IL-1β, IL-6, and TNF-α, in a time-dependent manner. Furthermore, we found that EP2-activated iNOS, COX2, and NLRP3 inflammasomes, and the TLR4/MAPK/NF-κB signaling pathway played an important role. Moreover, EP2 significantly increased the body weight, spleen index, thymus index, inflammatory cell counts, and the levels of IL-1β, IL-6, and TNF-α in CYP-induced immunosuppression mouse models. These results indicate that EP2 might be a potential immunomodulatory drug and provide the scientific basis for the comprehensive utilization and evaluation of E. prolifera in future applications.

Structural characterization and anti-lung cancer activity of a sulfated glucurono-xylo-rhamnan from Enteromorpha prolifera

A sulfated glucurono-xylo-rhamnan (EP-3-H) was purified from a green alga, Enteromorpha prolifera. EP-3-H and its oligomers were characterized by high performance liquid chromatography, mass spectrometry and one and two-dimensional nuclear magnetic resource spectroscopy. The structural analysis showed EP-3-H has a backbone of glucurono-xylo-rhamnan, branches with glucuronic acid and sulfated at C3 of rhamnose and/or C2 of xylose. The inhibition of EP-3-H on human lung cancer A549 cell proliferation in vitro and its therapeutic effects in BALB/c-nu mice in vivo were determined to evaluate the anti-lung cancer activity of EP-3-H. The tumor inhibition level was 59 %, suggesting that EP-3-H might be a good candidate for the treatment of lung cancer. Surface plasmon resonance (SPR) studies revealed the IC₅₀ on the binding of fibroblast growth factors, (FGF1 and FGF2), to heparin were 0.85 and 1.47 mg/mL, respectively. These results suggest that EP-3-H inhibits cancer proliferation by interacting with these growth factors.

Preparation and antibiofilm studies of curcumin loaded chitosan nanoparticles against polymicrobial biofilms of Candida albicans and Staphylococcus aureus

Polymicrobial biofilms related infections are an important clinical problem with classical antibiotics being not sufficient in therapy. Here, curcumin (Cur) was loaded on positively charged chitosan nanoparticles (CSNP). The antibiofilm activities against mono- and polymicrobial biofilms of Candida albicans and Staphylococcus aureus were evaluated. The average diameter of CSNP-Cur was 134.37 ± 1.99 nm and its surface charge was +18.10 ± 0.82 mV. Cur released from NPs was slower at pH 7.4 than at pH 5.4. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to observe biofilm architecture and live/dead organisms within biofilm on medical silicone surface. CSNP-Cur exhibited excellent antibiofilm activity against planktonic bacteria or fungi, mono- and polymicrobial biofilm formations and preformed biofilms. SEM and CLSM showed that CSNP-Cur was able to reduce biofilm thickness as well as kill microbial cells embedded in biofilm on silicone surfaces.

Anticancer efficacy of 6-thioguanine loaded chitosan nanoparticles with or without curcumin

6-Thioguanine encapsulated chitosan nanoparticles (6-TG-CNPs) has formulated by the ionic-gelation method. Morphologically, the 6-TG-CNPs were spherical and showed mean size, PDI, zeta potential, and entrapment efficiency of 261.63 ± 6.01 nm, 0.34 ± 0.10, +15.97 ± 0.46 mV and 44.27%, respectively. The IR spectra confirmed the 6-TG complex with chitosan. The in vitro drug release profile of 6-TG-CNPs revealed an increase in sustained-release (91.40 ± 1.08% at 48 h) at pH 4.8 compared to less sustained-release (73.96 ± 1.12% at 48 h) at pH 7.4. The MTT assay was conducted on MCF-7 and PA-1 cell lines at 48 h incubation to determine % cell viability. The IC₅₀ values of 6-TG, 6-TG-CNPs, and curcumin for MCF-7 were 23.09, 17.82, and 15.73 μM, respectively. Likewise, IC₅₀ values of 6-TG, 6-TG-CNPs, and curcumin for PA-1 were 5.81, 3.92, and 12.89 μM, respectively. A combination of 6-TG-CNPs (IC₂₅) with curcumin (IC₂₅) on PA-1 and MCF-7 showed % cell viability of 43.67 ± 0.02 and 49.77 ± 0.05, respectively. The in vitro cytotoxicity potential in terms of % cell viability, early apoptosis, G2/M phase arrest, and DNA demethylating activity of 6-TG-CNPs alone and combination with curcumin proved to be more effective than that of 6-TG on PA-1 cells.

Polysaccharides from Enteromorpha prolifera protect against carbon tetrachloride-induced acute liver injury in mice via activation of Nrf2/HO-1 signaling, and suppression of oxidative stress, inflammation and apoptosis

EPP protected against hepatic injury induced by CCl₄-derived reactive intermediates through the suppression of hepatic oxidative stress, inflammation, and apoptosis.

Polysaccharides from Enteromorpha Prolifera Ameliorate Acute Myocardial Infarction in Vitro and in Vivo via Up-Regulating HIF-1α

Acute myocardial infarction (AMI) is a serious heart disease and the main reason for heart failure and sudden death worldwide. This study investigated the effects of polysaccharides from Enteromorpha prolifera (PEP) on AMI in vitro and in vivo, as well as the underlying mechanisms.Human cardiac microvascular endothelial cells (HCMVEC) were cultured in vitro in an oxygen-glucose deprivation (OGD) environment to induce injury. The viability and apoptosis of HCMVEC were then detected using CCK-8 assay and Annexin V-FITC/PI staining, respectively. ELISA was performed to measure the concentrations of inflammatory cytokines. Cell transfection was conducted to reduce the expression of HIF-1α. Expression of key factors involving in cell proliferation, apoptosis, autophagy, MEK/ERK, and the NF-κB and mTOR pathways were evaluated using Western blotting. In vivo, Wistar rats were pre-treated by PEP and AMI was induced. The infarct size and cardiac functions (LVEDD, LVEF and LVFS) were measured.In vitro, PEP treatment significantly protected HCMVEC from OGD-induced viability loss, proliferation inhibition, apoptosis, inflammatory cytokine expression, and autophagy. Moreover, PEP enhanced the expression of HIF-1α in HCMVEC via the MEK/ERK pathway. HIF-1α participated in the protective effects of PEP on OGD-treated HCMVEC. Furthermore, PEP attenuated OGD-induced NF-κB pathway activation and promoted the mTOR pathway in HCMVEC. In vivo, PEP pre-treatment reduced the infarct size and enhanced the LVEDD, LVEF and LVFS of rats via up-regulation of HIF-1α.PEP ameliorated AMI in vitro and in vivo through up-regulation of HIF-1α. In vitro, PEP could activate the MEK/ERK and mTOR pathways, but inactivate the NF-κB pathway in OGD-treated HCMVEC.

Advances in phytochemical delivery systems for improved anticancer activity

Natural compounds have significant anticancer pharmacological activities, but often suffer from low bioavailability and selectivity that limit therapeutic use. The present work critically analyzes the latest advances on drug delivery systems designed to enhance pharmacokinetics, targeting, cellular uptake and efficacy of anticancer phytoconstituents. Various phytochemicals, including flavonoids, resveratrol, celastrol, curcumin, berberine and camptothecins, carried by liposomes, nanoparticles, nanoemulsions and films showed promising results. Strategies to avoid drug metabolism, overcome physiological barriers and achieve higher concentration at cancer sites through skin, buccal, nasal, vaginal, pulmonary and colon targeted delivery are presented. Current limitations, challenges and future research directions are also discussed.

Raloxifene/SBE-β-CD Inclusion Complexes Formulated into Nanoparticles with Chitosan to Overcome the Absorption Barrier for Bioavailability Enhancement

Raloxifene (RXF) is a hormone-like medication used for treating postmenopausal osteoporosis and estrogen-dependent breast cancer, yet associated with bad low bioavailability due to poor solubility. This study was intended to develop cyclodextrin/chitosan nanoparticles (ccNPs) for oral delivery of RXF in order to enhance the oral bioavailability. RXF-loaded ccNPs (RXF-ccNPs) were prepared by cyclodextrin inclusion followed by complexation with chitosan. RXF-ccNPs were fully characterized by particle size, morphology and in vitro drug release. The oral delivery efficacy and transepithelial transport potential were evaluated by pharmacokinetics, in situ single-pass intestinal perfusion, cellular uptake and ex vivo imaging. The resulting RXF-ccNPs were around 165 nm in particle size with a narrow distribution. The oral bioavailability of RXF was enhanced by 2.6 folds through ccNPs compared to RXF suspensions in rats. It was shown that RXF-ccNPs could improve the intestinal permeability of RXF, increase the cellular uptake of RXF and facilitate its transport across the absorptive epithelia. The results indicate that our developed ccNPs based on sulfobutylether-β-cyclodextrin and oligochitosan are a promising vehicle to orally deliver poorly water-soluble drugs over and above RXF.