Recent developments in curcumin and curcumin based polymeric materials for biomedical applications: A review

Iodine Immobilized Metal-Organic Framework for NIR-Triggered Antibacterial Therapy on Orthopedic Implants

Iodine has been known as an effective disinfectant with broad-spectrum antimicrobial potency yet without drug resistance risk when used in clinic. However, the exploration of iodine for antibacterial therapy in orthopedics remains sparse due to its volatile nature and poor solubility. Herein, leveraging the superior absorption capability of metal-organic frameworks (MOFs) and their inherent photocatalytic properties, iodine-loaded MOF surface is presented to realize responsive iodine release along with intracellular reactive oxygen species(ROS) oxidation under near-infrared (NIR) exposure to achieve synergistic antibacterial effect. Iodine is successfully loaded using vapor deposition process onto zeolitic imidazolate framework-8(ZIF-8), which is immobilized onto micro arc oxidized titanium via a hydrothermal approach. The combination of NIR-triggered iodine release and ZIF-8 mediated ROS oxidative stress substantially augments the antibacterial efficacy of this approach both in vitro and in vivo. Furthermore, this composite coating also supported osteogenic differentiation of bone marrow stromal cells, as well as improved osseointegration of coated implants using an intramedullary rat model, suggesting improvement of antibacterial efficacy does not impair osteogenic potential of the implants. Altogether, immobilization of iodine via MOF on orthopedic implants with synergistic antibacterial effect can be a promising strategy to combat bacterial infections.

Protective effects of curcumin against methotrexate-induced testicular damage in rats by suppression of the p38-MAPK and nuclear factor-kappa B pathways

Objective

The present study aimed to investigate the possibility that curcumin (CMN) protects against methotrexate (MTX)-induced testicular damage by affecting the phospho-p38 (p-p38) mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways.

Methods

Eighteen male Wistar albino rats were randomly divided into three groups. The control group was given an intragastric administration of dimethyl sulfoxide (DMSO) daily for 14 days, the MTX group was given a single intraperitoneal dose of MTX (20 mg/kg) on the 11th day, and the MTX+CMN group was given intragastric CMN (100 mg/kg/day, dissolved in DMSO) for 14 days and a single intraperitoneal dose of MTX (20 mg/kg) on the 11th day. At the end of the experiment, all animals were sacrificed and the testicular tissues were removed for morphometry, histology, and immunohistochemistry. Body and testicular weights were measured.

Results

Body weights, seminiferous tubule diameter, and germinal epithelium height significantly decreased in the MTX group compared to the control group. Whereas, the number of histologically damaged seminiferous tubules and interstitial space width significantly increased in the MTX group. In addition, the number of p-p38 MAPK immunopositive cells and the immunoreactivity of NF-κB also increased in the MTX group compared to the control group. CMN improved loss of body weight, morphometric values, and histological damage due to MTX. CMN also reduced the number of p-p38 MAPK immunopositive cells and the NF-κB immunoreactivity.

Conclusion

CMN may reduce MTX-induced testicular damage by suppressing the p38 MAPK and NF-κB signaling pathways.

Phosphate Adsorption from Aqueous Solution Using Electrospun Cellulose Acetate Nanofiber Membrane Modified with Graphene Oxide/Sodium Dodecyl Sulphate

Eutrophication and water pollution caused by a high concentration of phosphate are two concerning issues that affect water quality worldwide. A novel cellulose-based adsorbent, cellulose acetate/graphene oxide/sodium dodecyl sulphate (CA/GO/SDS), was developed for water treatment. A 13% CA solution in a mixture of acetone:dimethylacetamide (2:1) has been electrospun and complexed with a GO/SDS solution. The field emission scanning electron microscope (FESEM) showed that the CA membrane was pure white, while the CA/GO/SDS membrane was not as white as CA and its colour became darker as the GO content increased. The process of phosphate removal from the solutions was found to be aided by the hydroxyl groups on the surface of the CA modified with GO/SDS, as shown by infrared spectroscopy. An optimization condition for the adsorption process was studied by varying pH, immersion time, and the mass of the membrane. The experimental results from phosphate adsorption showed that CA/GO/SDS had an excellent pH adaptability, with an optimum pH of 7, and maximum removal (>87.0%) was observed with a membrane mass of 0.05 g at an initial concentration of 25 mg L^-1. A kinetic study revealed that 180 min of contact time could adsorb about 87.2% of phosphate onto the CA/GO/SDS membrane. A typical pseudo-second-order kinetic model successfully portrayed the kinetic sorption of phosphate, and the adsorption equilibrium data were well-correlated with the Langmuir adsorption model, suggesting the monolayer coverage of adsorbed molecules.

A review of stimuli-responsive polymeric micelles for tumor-targeted delivery of curcumin

Despite a potential drug with multiple pharmacological activities, curcumin has disadvantages of the poor water solubility, rapid metabolism, low bioavailability, which considerably limit its clinical application. Currently, polymeric micelles (PMs) have gained widespread concern due to their advantageous physical and chemical properties, easy preparation, and biocompatibility. They can be used to improve drug solubility, prolong blood circulation time, and allow passive targeted drug delivery to tumor through enhanced penetration and retention effect. Moreover, studies focused on tumor microenvironment offer alternatives to design stimulus-responsive smart PMs based on low pH, high levels of glutathione, altered enzyme expression, increased reactive oxygen species production, and hypoxia. There are various external stimuli, such as light, ultrasound, and temperature. These endogenous/exogenous stimuli can be used for the research of intelligent micelles. Intelligent PMs can effectively load curcumin with improved solubility, and intelligently respond to release the drug at a controlled rate at targeted sites such as tumors to avoid early release, which markedly improves the bioavailability of curcumin. The present review is aimed to discuss and summarize recent developments in research of curcumin-loaded intelligent PMs based on endogenous and exogenous stimuli, and facilitates the development of novel delivery systems for future research.

A new biodegradable nano cellulose-based drug delivery system for pH-controlled delivery of curcumin

Targeted delivery and controlled release of drugs are attractive methods for avoiding the drug's leakage during blood circulation and burst release of the drug. We prepared a nano cellulose-based drug delivery system (DDS) for the effective delivery of curcumin (CUR). In the present scenario, the role of nanoparticles in fabricating the DDS is an important one and was characterized using various techniques. The drug loading capacity was high as 89.2% at pH = 8.0, and also the maximum drug release takes place at pH = 5.5. In vitro cell viability studies of DDS on MDA MB-231; breast cancer cells demonstrated its cytotoxicity towards cancer cells. The prepared DDS was also examined for apoptosis, hemocompatibility, and Chorioallantoic membrane (CAM) studies to assess its pharmaceutical field application and the investigation results recommended that it may serve as a potential device for targeted delivery and controlled release of CUR for cancer treatment.

The curcumin analog (PAC) suppressed cell survival and induced apoptosis and autophagy in oral cancer cells

PAC (3,5-Bis (4-hydroxy-3-methoxybenzylidene)-N-methyl-4-piperidone), a novel bioactive curcumin analog, has been reported to have anticancer properties against various tumors. However, the anti-cancer effects of PAC on oral cavity squamous cell carcinoma were not studied yet. Our aim is to investigate the anti-oral cancer properties of PAC in vitro, and determine the molecular mechanisms underlying these effects. Viability assays including MTT and LDH were conducted to measure cell proliferation. Flow cytometry-based cytotoxicity assay was performed to detect autophagic cell death and oxidative stress markers. Western blotting was used for measuring protein expression/activation in apoptotic, autophagic and pro-carcinogenic cellular signaling pathways. We demonstrated that PAC preferentially and, in a dose, -dependent way kills oral cancer cells, but was not toxic to normal human gingival cells. PAC destabilizes cell-cycle distributions, inhibits the expression of oncogenes (cyclin D1) and that of cyclin-dependent kinase inhibitor (p21^WAF1) is upregulated, increases the expression of p53 gene, and inhibits epithelial-mesenchymal transition markers in oral cancer cells. The PAC effect involve various signaling pathways including NF-κB, MAPK, Wnt, caspase-3/9 and PARP1. Finally, PAC demonstrated ability to induce autophagy, decrease production of reactive oxygen species, increase intracellular glutathione (GSH) activity, and reduce mitochondrial membrane potential in oral cancer cells. In conclusion, PAC inhibits the proliferation and increases the apoptosis and autophagy and oxidative stress of oral cancer cells. These effects involve ERK1/2, p38/JNK, NF-κB and Wnt cellular signaling pathways. Overall, our study suggests the potential use of PAC to treat oral cancer.

Delivery of curcumin using a zein-xanthan gum nanocomplex: Fabrication, characterization, and in vitro release properties

This study aimed to use xanthan gum as a stabilizer to improve the stability of zein nanoparticles. Zein-xanthan gum composite nanoparticles were prepared via anti-solvent precipitation at pH 4.0. The particle size, zeta potential, and stability of the system were related to the amount of xanthan gum added. When 20 mg of xanthan gum was added, spherical nanoparticles with a small particle size (179 ± 2.1 nm) and sufficient negative zeta potential (-42 ± 1.6 mV) were obtained. The zeta potential and Fourier transform infrared spectroscopy results indicated that electrostatic attraction was the main driving force, followed by hydrogen bonding and hydrophobic interactions. Composite nanoparticles were coated by xanthan gum and remained stable over a wide pH range and at high temperatures and salt concentrations; they did not precipitate or aggregate after 30 days of storage. Moreover, the addition of xanthan gum considerably improved the encapsulation efficiency and loading capacity of nanoparticles containing high curcumin amounts, which facilitated slow and sustained release of curcumin in simulated intestinal fluid. Therefore, zein-xanthan gum nanoparticles can be used for the delivery of biologically active compounds in food and pharmaceutical preparations.

Potential protective roles of curcumin against cadmium-induced toxicity and oxidative stress

Curcumin, used as a spice and traditional medicine in India, exerts beneficial effects against several diseases, owing to its antioxidant, analgesic, and anti-inflammatory properties. Evidence indicates that curcumin might protect against heavy metal-induced organ toxicity by targeting biological pathways involved in anti-oxidation, anti-inflammation, and anti-tumorigenesis. Curcumin has received considerable attention owing to its therapeutic properties, and the mechanisms underlying some of its actions have been recently investigated. Cadmium (Cd) is a heavy metal found in the environment and used extensively in industries. Chronic Cd exposure induces damage to bones, liver, kidneys, lungs, testes, and the immune and cardiovascular systems. Because of its long half-life, exposure to even low Cd levels might be harmful. Cd-induced toxicity involves the overproduction of reactive oxygen species (ROS), resulting in oxidative stress and damage to essential biomolecules. Dietary antioxidants, such as chelating agents, display the potential to reduce Cd accumulation and metal-induced toxicity. Curcumin scavenges ROS and inhibits oxidative damage, thus resulting in many therapeutic properties. This review aims to address the effectiveness of curcumin against Cd-induced organ toxicity and presents evidence supporting the use of curcumin as a protective antioxidant.

Curry versus cancer: Potential of some selected culinary spices against cancer with in vitro, in vivo, and human trials evidences

Spices are dietary agents with immense potential for cancer chemo-prevention. A wide variety of spices are extensively used as food flavoring agents which possess potent antioxidant, anti-inflammatory, and anticancer properties due to the presence of certain bio-active compounds in them. In vitro, in vivo studies and clinical trials of selected spices against various types of cancer are being specified in this review. Effect of certain putative dietary spices namely turmeric, clove, garlic, ginger, fennel, black cumin, cinnamon, pepper, saffron, rosemary, and chilli along with its role in cancer are being discussed. Literature search was conducted through PubMed, Google scholar, Science direct, and Scopus using the keywords "spice," "cancer," "natural medicine," "herbal compound," "bioactive compounds." About 4,000 published articles and 127 research papers were considered to grab the brief knowledge on spices and their anticancer potential on a predefined inclusion and exclusion criteria. PRACTICAL APPLICATION: Historically, spices and herbs are known for its traditional flavor, odor, and medicinal properties. Intensified risk of chronic and pervasive clinical conditions and increased cost of advanced drug treatments have developed a keen interest among researchers to explore the miscellaneous properties of herbal spices. Cancer is one of the deleterious causes of mortality affecting a huge number of populations worldwide. Arrays of cancer treatments including surgery, chemotherapy, and radiation therapy are used to compromise the disease but effective only when the size of the tumor is small. So, an effective treatment need to be developed that produces less side effects and herbal spices are found to be the promising agents. In this review, we illustrate about different in vitro, in vivo, and clinical studies of wide range of culinary spices having antineoplastic potential.

Curcumin micelles entrapped in eudragit S-100 matrix: a synergistic strategy for enhanced oral delivery

Background:

Therapeutic activities of curcumin (CUR) via oral administration are hampered by the lack of bioavailability due to its poor water solubility and rapid degradation in GI tract.

Materials & methods:

This preliminary study developed CUR micelle-eudragit S100 (EUD) dry powder (CM-EDP) spray-dried formulations. Poloxamer 407 was used as a micelle-forming agent and EUD as an entrapping matrix for protection over hydrolysis and enzymes in the GI tract.

Results:

The morphology of CM-EDP showed agglomeration with cratering on the surface of particles. Differential thermal analysis and x-ray diffractometry data exhibited evidence that CUR was converted into amorphous solid. An increased concentration of micelle-forming and dispersion matrix polymers resulted in a high fraction of drug being converted into the amorphous state. A significant increase in dissolution by 7–10 times was achieved compared with that of raw CUR.

Conclusion:

The present study disclosed the CM-EDP potency for future development of CUR oral formulation.

Curcumin (CUR) is a natural compound that shows several pharmacological activities, including anti-inflammatory and potential actions against Parkinson’s and Alzheimer’s. However, several drawbacks need to be addressed its application as a therapeutic agent via oral administration. These drawbacks include its poor water solubility and rapid degradation in the GI tract. The present study developed CUR micelle-eudragit S100 (EUD) dry powder formulation involving poloxamer 407 as solubilizing agent and EUD as entrapping matrix for protection in acidic environments and the enzymes in the GI tract. The final product is in the form of dry powder, which showed potency in enhancing CUR absorption following oral administration.

Fabrication of a narrow size nano curcuminoid emulsion by combining phase inversion temperature and ultrasonication: preparation and bioactivity

A novel method to prepare narrow size nano curcuminoids from Curcuma longa.

Unique flower-like Cur-metal complexes loaded liposomes for primary and metastatic breast cancer therapy

Mounting researches continue to support a favorable role for the drug metal complex against cancer progress and metastasis. However, pharmaceutical barriers were encountered when drug metal complexes needed further pre-clinical and clinical evaluations due to their poor aqueous solubility. In this research, liposomes loaded metal ion as nano-scaled reaction vehicles were used to carry out a synthesis reaction between metal ion and curcumin (Cur) to prepare Cur-metal drug liposomal formulations. The unique flower-like conformation of Cur-M liposomes was observed for the first time and dominated in the Cur-M liposomal formulations system by the cryo-transmission electron microscopy. Different metal ions behaved significant differences in formulations' appearance, release profile, cytotoxic effect against various cell lines, pharmacokinetic profiles, biodistribution and antitumor efficiency. Cur-M liposomes presented enhanced cellular uptake and ROS generation effects, thus augmenting the cytotoxicity of Cur. Superior performances of Cur-copper complexes liposomes were observed in improving Cur stability, promoting apoptosis, inhibiting the proliferation and angiogenesis, therefore enhancing therapeutic effect for primary and metastatic breast cancer. Overall, the current work highlights the potentially significant development value of Cur-M liposomes as an injectable agent for cancer treatment, even superior to the commercial agent Doxil.

Novel Herbal Topical Patch Containing Curcumin and Arnica montana for the Treatment of Osteoarthritis

BACKGROUND

Osteoarthritis (OA) ranks fifth among all forms of disability affecting 10% of the world population. Current treatments available are associated with multiple side effects and do not slow down the progression of the disease. Moreover, no such effective treatment is available to date in various systems of medicine to treat osteoarthritis. Curcumin and Arnica have shown evident clinical advances in the treatment of osteoarthritis.

OBJECTIVE

The aim of the present study was to design, optimize and characterize novel herbal transdermal patches of curcumin and Arnica montana using factorial design.

METHODS

A multiple factorial design was employed to investigate the effect of hydroxypropyl methyl cellulose, ethyl cellulose and jojoba oil on elongation and drug release. Transdermal patches were evaluated by FTIR, DSC, FESEM, ex vivo drug permeation, anti osteoarthritic activity and analgesic activity.

RESULTS

Independent variables exhibited a significant effect on the physicochemical properties of the prepared formulations. The higher values of drug release and elongation were observed with the higher concentration of hydroxypropyl methylcellulose and jojoba oil. Anti osteoarthritic activity was assessed by complete Freund's adjuvant arthritis model; using rats and analgesic activity by Eddy's hot plate method, using mice. Combination patch exhibited good anti osteoarthritic and analgesic activity as compare to individual drug patches.

CONCLUSION

The design results revealed that the combination patch exhibited good physicochemical, anti osteoarthritic and analgesic activity for the treatment of osteoarthritis in animals. More plants and their combinations should be explored to get reliable, safe and effective formulations that can compete with synthetic drugs.

Preparation, characterization, antioxidant evaluation of new curcumin derivatives and effects of forming HSA-bound nanoparticles on the stability and activity

Curcumin (CCM) is a well-known active component, which has been studied extensively in food and medicine field since it showed various activities. However, some serious issues limit its application, for example, the extremely low solubility, stability and bioavailability. In this study, 10 Curcumin derivatives were synthesized and characterized by ¹H NMR, ¹³C NMR and HR-MS, then their antioxidant activity was evaluated. Compound 2 and curcumin were further investigated by preparing HSA-bound nanoparticles (NP-2 and NP-CCM) to surmount the difficulties mentioned above. The nanoparticles obtained were about 110 nm in size measured by Dynamic light scattering (DLS), the stability of compound 2 in NP-2 was significantly increased. Above all, NP-2 showed more efficient antioxidant and antitumor activity, which was probably attributed to the introduced isopentenyl groups in 2, it was supposed that the isopentenyl groups increased the interaction between compound 2 and HSA. Overall, NP-2 has great potential for some food and pharmaceutical applications.

Assembly of propylene glycol alginate/β-lactoglobulin composite hydrogels induced by ethanol for co-delivery of probiotics and curcumin

Probiotics and curcumin can exhibit synergistic biological activities on the basis of a gut-brain axis, but are sensitive to environmental conditions, making it a challenge for their co-utilization. To meet the demand for high efficiency and convenience, both probiotics and curcumin were encapsulated within a propylene glycol alginate-based hydrogel delivery system, which was assembled using an ethanol-induced approach. The composite hydrogel was effective at sustaining the release of curcumin and protecting LGG cells in simulated gastrointestinal tract conditions. Moreover, it could also largely reduce the chemical degradation of curcumin and increase the survival of LGG during light exposure and long-term storage: up to 91.3 % of curcumin and 9.72 log CFU cm^-3 remained present throughout 4 weeks of storage. Results in this work demonstrate a low-energy and green approach to assemble a composite hydrogel with remarkable biocompatibility, which is considered as a desired delivery vehicle for co-delivery of probiotics and curcumin.

pH-responsive hyaluronic acid-based nanoparticles for targeted curcumin delivery and enhanced cancer therapy

Curcumin (CUR) display promising antitumor effects, however, the poor water solubility severely limited its clinical application. To overcome this problem, polymeric nanocarriers have been adopted for targeted CUR delivery and enhanced cancer therapy. In this paper, utilizing an acid-labile hydrazone linkage, hydrophobic CUR was conjugated with hydrophilic hyaluronic acid (HA) to form amphiphilic HA-ADH-CUR conjugates, which could subsequently self-assemble to form nanoparticles (HA@CUR NPs) in aqueous. The in vitro drug release experiments showed that HA@CUR NPs exhibited a pH-responsive CUR release behavior, and the release rate of CUR was 73.5 % in pH 5.0. Further, in vitro cell experiments showed HA@CUR NPs could be efficiently internalized by 4T1 and MCF-7 cancer cells through CD44 receptor mediated endocytosis and successfully release CUR in acidic lysosome environment for chemotherapy. In vivo antitumor experiments showed that, compared to free CUR, HA@CUR NPs could efficiently cumulate in tumor site via EPR effect and CD44 mediated endocytosis, achieve superior therapeutic effect for tumor growth suppression. Therefore, HA@CUR NPs were a highly promising nanocarrier for hydrophobic CUR to realize enhanced cancer therapy with good biosafety.

Enhanced curcumin solubility and antibacterial activity by encapsulation in PLGA oily core nanocapsules

Infections caused by bacteria represent an emerging public health threat due to the development of antibiotic resistance in bacteria. Curcumin (CUR), a naturally derived substance, is found to be effective against several bacteria. However, its use is limited by its low water solubility and rapid degradation profile. Polymeric nanocapsules (NCs) represent an interesting drug delivery system with high incorporation rates due to their liquid core. The present study aimed to develop poly-(lactic-co-glycolic acid) (PLGA) NCs for the delivery of CUR for enhancing its solubility and antibacterial activity. The particle size, polydispersity index (PDI), zeta potential and drug entrapment efficiency of CUR NCs with optimal formulation were 158 nm, 0.156, -29.1 mV and 92.64%, respectively. The water solubility of CUR in NCs increased about 1500 fold compared to that of free CUR. TEM and AFM images proved the core-shell structure of PLGA NCs with narrow size distributions. The in vitro release profile of CUR from PLGA NCs showed a burst release in the initial 24 h followed by a sustained release of the interior CUR over 10 days. In vitro antibacterial experiments demonstrate that the minimum inhibitory concentrations (MICs) of CUR NCs were lower than those of free CUR for all different bacterial strains, especially for Gram-negative bacteria. CUR NCs exhibited broad-spectrum antibacterial effects compared with free CUR. These data suggest that these CUR-loaded PLGA NCs may provide a promising strategy as novel antibacterial agents.

Effect of the Single and Combined Use of Curcumin and Piperine on Growth Performance, Intestinal Barrier Function, and Antioxidant Capacity of Weaned Wuzhishan Piglets

This study was conducted to evaluate effects of the single and combined use of curcumin (CUR) and piperine (PIP) on performance, intestinal barrier function, and antioxidant capacity of weaned piglets. A total of 50 Wuzhishan piglets weaned at 35 days of age were randomly assigned to five groups receiving a corn–soybean basal diet (CON), the basal diet supplemented with 50 mg/kg piperine, 200 mg/kg curcumin (low-CUR), 200 mg/kg curcumin + 50 mg/kg piperine (PIP + CUR), and 300 mg/kg curcumin (high-CUR), respectively. The results showed that the feed/gain ratio (F/G) and plasma d-lactate and diamine oxidase activity (DAO) of the CUR + PIP and high-CUR groups were lower than those of the CON group (all P < 0.05), while the jejunum and ileum villus height, the villus height/crypt depth ratio, and the messenger RNA (mRNA) expression levels of occludin, claudin-1, and zonula occluden-1 in jejunal and ileal mucosa were higher in the CUR + PIP and high-CUR groups than in the CON group (all P < 0.05). Moreover, the piglets in the CUR + PIP and high-CUR groups had higher serum and intestinal mucosa activity of superoxide dismutase and glutathione peroxidase and lower malonaldehyde concentration than piglets in the CON group (all P < 0.05). The above parameters were not significantly different between the CUR + PIP and high-CUR groups (P > 0.05). In conclusion, the combination of CUR and PIP seemed to be as advantageous as high-CUR to piglets, but it was more effective than the single use of CUR and PIP. These data indicated that the basal diet supplemented with CUR + PIP or high-CUR could improve the intestinal permeability and suppress oxidative stress of weaned Wuzhishan piglets.

The potential use of curcumin-β-cyclodextrin inclusion complex/chitosan-loaded cellulose sponges for the treatment of chronic wound

In this research, the cellulose sponges with curcumin-β-cyclodextrin inclusion complex (CMx) and chitosan (CS) were fabricated for use as wound dressings. 1-Allyl-3-methylimidazolium chloride (AMIMCl) ionic liquid as a green solvent was used for the fabrication of cellulose sponges. Due to the low aqueous solubility and low bioavailability of curcumin, cyclodextrins (CDs) were applied and complexed with curcumin to obtain CMx. In addition, CS was incorporated in the cellulose sponges to improve the antibacterial activity of sponges. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) analysis, morphological appearances, mechanical properties, water retention and weight loss, release behaviors, antibacterial activity, indirect cytotoxicity, cell attachment, and cell proliferation of the CMx/CS-loaded cellulose sponges were investigated. From the results, the cellulose sponges showed a porous structure. The incorporation of CMx and CS improved the mechanical properties when compared to the neat cellulose sponges. Moreover, the addition of CS into the cellulose sponges exhibited antibacterial activity against E. coli and S. aureus. Furthermore, the indirect cytotoxicity of the CMx/CS-loaded cellulose sponges was non-toxic and compatible with NCTC L929 and NHDF cells. Consequently, the CMx/CS-loaded cellulose sponges might be good candidates for use as wound dressing materials for the treatment of wound, especially chronic wound.

Recent Advances in Polymeric Nanoparticle-Encapsulated Drugs against Intracellular Infections

Polymeric nanocarriers (PNs) have demonstrated to be a promising alternative to treat intracellular infections. They have outstanding performance in delivering antimicrobials intracellularly to reach an adequate dose level and improve their therapeutic efficacy. PNs offer opportunities for preventing unwanted drug interactions and degradation before reaching the target cell of tissue and thus decreasing the development of resistance in microorganisms. The use of PNs has the potential to reduce the dose and adverse side effects, providing better efficiency and effectiveness of therapeutic regimens, especially in drugs having high toxicity, low solubility in the physiological environment and low bioavailability. This review provides an overview of nanoparticles made of different polymeric precursors and the main methodologies to nanofabricate platforms of tuned physicochemical and morphological properties and surface chemistry for controlled release of antimicrobials in the target. It highlights the versatility of these nanosystems and their challenges and opportunities to deliver antimicrobial drugs to treat intracellular infections and mentions nanotoxicology aspects and future outlooks.

Nutraceutical nanodelivery; an insight into the bioaccessibility/bioavailability of different bioactive compounds loaded within nanocarriers

Nanofoods is a current concept that is based on the application of nanotechnologies in the preparation of safe foods, with superior nutritional and sensory characteristics, and capable of providing multiple health benefits. In line with the principles of this concept, food scientists have focused on developing new types of nano biosystems that can contribute to increasing the bioavailability of bioactive compounds used in food fortification. Numerous research teams have investigated the main factors limiting oral bioavailability including: bioaccessibility, absorption and transformation of bioactive compounds and bioactive-loaded nanocarriers. The physicochemical processes involved in the factors limiting oral bioavailability have been extensively studied, such asthe release, solubility and interaction of bioactive compounds and nanocarriers during food digestion, transport mechanisms of bioactive compounds and nanoparticles through intestinal epithelial cells as well as the chemical and biochemical transformations in phase I and phase II reactions. In this comprehensive review, the physicochemical processes involved in the bioaccessibility/bioavailability of different encapsulated bioactive compounds, that play an important role in human health, will be explained including polyphenols, phytosterols, carotenoids, vitamins and minerals. In particular, the mechanisms involved in the cellular uptake of bioactive-loaded nanocarriers including transcellular transport (diffusion, endocytosis, pinocytosis, transcytosis, phagocytosis), paracellular transport (through the "tight junctions" between epithelial cells), and the active transport of bioactive compounds under the action of membrane transporters are highlighted.

Application of aeration-assisted homogeneous liquid-liquid microextraction procedure using Box-Behnken design for determination of curcumin by HPLC

A simple, efficient, and rapid sample preparation method based on aeration-assisted homogeneous liquid-liquid microextraction was developed for determination of curcumin in food samples by high-performance liquid chromatography. The centrifuge step has been eliminated in this procedure. The effects of some variables, such as pH, volume of extraction solvent, extraction time, and salt effect, were studied through a Box-Behnken design method. Under the optimum conditions, calibration curves of curcumin were linear in the range of 0.08-4000 μg/mL with R2  = 0.997. Limit of detection and relative standard deviation were 0.019 μg/mL and 3.01%, respectively. The preconcentration factor achieved was 166. The proposed method was successfully applied to determination of curcumin in various food samples.

Development of curcumin-loaded chitosan/pluronic membranes for wound healing applications

The emergence of new materials with improved antibacterial, anti-inflammatory and healing properties compared to conventional wound dressings has both social and economic appeal. In this study, novel chitosan-based (CTS) membranes containing curcumin (CUR) incorporated in Pluronic (PLU) copolymers were developed and characterized to obtain suitable properties for applications as a wound healing dressing. The mechanical, thermal, swelling, wettability, release and permeation properties were evaluated by DSC, TGA, water contact angle measurements, FTIR, fluorescence and microscopic techniques. Membranes containing PLU and CUR presented wettability close to the ideal range for interaction with cellular components (contact angle ~40-70°), improved mechanical properties, higher thermal stability, high swelling degree (>800%) and CUR release (~60%) compared to samples without PLU addition. A higher retention of CUR in the epidermis than in the dermis layer was observed, which also was confirmed by confocal microscopy. Furthermore, the CTS-PLU membranes loaded with CUR showed to be active against Staphylococcus aureus and Pseudomonas aeruginosa (MIC = 25 and 100 mg mL^-1, respectively), the microbial species most present in chronic wounds. Overall, the CTS-PLU-CUR membranes presented suitable properties to act as a new wound healing dressing formulation and in vivo studies should be performed to confirm these benefits.

Curcumin-loaded lipid-core nanocapsules attenuates the immune challenge LPS-induced in rats: Neuroinflammatory and behavioral response in sickness behavior

The purpose of current study was to evaluate the effect of curcumin (CUR) loaded lipid-core nanocapsules (CUR-LNC) treatment on neuroinflammatory and behavioral alterations in a model of sickness behavior induced by lipopolysaccharide (LPS) in rats. Rats were treated with CUR-LNC and CUR daily for 14 days. After the last treatments, sickness behavior was induced with LPS. Sickness behavior LPS-induced was confirmed by behavioral tests, an increase in levels of proinflammatory cytokines, decrease in levels of IL-10, overexpression of IDO-1 and IDO-2. In conclusion, CUR-LNC treatment attenuated the neuroinflammatory and behavioral changes caused in sickness behavior model.

Preparation and evaluation of curcumin grafted hyaluronic acid modified pullulan polymers as a functional wound dressing material

Curcumin grafted hyaluronic acid modified pullulan polymers (Cur-HA-SPu) by chemical conjugation was designed and prepared, and its film may be used to accelerate wound healing and help to fight infection. The synthesis of Cur-HA-SPu polymer was characterized by FT-IR, ¹H NMR and DSC. Cur-HA-SPu film has a higher swelling ratio than that of HA-SPu film. Moreover, the good biocompatibility of Cur-HA-SPu polymer was confirmed by skin irritation, cytotoxicity and hemolysis tests. Compared to Cur, the MTT and proliferation test carried out in L929 cells revealed that Cur-HA-SPu polymer showed no cytotoxicity and enhanced cell proliferation. Cur-HA-SPu polymer exhibited a certain bactericidal activity against E. coli and S. aureus. Furthermore, the materials showed antioxidant activity when DPPH method determined. Wound healing study using wistar rat model demonstrated that Cur-HA-SPu film obtained better wound healing result than that of HA-SPu film or natural healing. The above results suggest that Cur-HA-SPu film is a promising and safety formulation for accelerating skin wound healing.

Therapeutic Applications of Curcumin Nanomedicine Formulations in Cardiovascular Diseases

Cardiovascular diseases (CVD) compromises a group of heart and blood vessels disorders with high impact on human health and wellbeing. Curcumin (CUR) have demonstrated beneficial effects on these group of diseases that represent a global burden with a prevalence that continues increasing progressively. Pre- and clinical studies have demonstrated the CUR effects in CVD through its anti-hypercholesterolemic and anti-atherosclerotic effects and its protective properties against cardiac ischemia and reperfusion. However, the CUR therapeutic limitation is its bioavailability. New CUR nanomedicine formulations are developed to solve this problem. The present article aims to discuss different studies and approaches looking into the promising role of nanotechnology-based drug delivery systems to deliver CUR and its derivatives in CVD treatment, with an emphasis on their formulation properties, experimental evidence, bioactivity, as well as challenges and opportunities in developing these systems.

Curcumin- and Piperine-Loaded Emulsomes as Combinational Treatment Approach Enhance the Anticancer Activity of Curcumin on HCT116 Colorectal Cancer Model

Combination chemotherapy, administrating two chemotherapeutic agents concurrently, comes into prominence, as the heterogeneity or the level of the disease necessitates a collaborative action. Curcumin, isolated from turmeric, and piperine, isolated from black long pepper, are two dietary polyphenols studied for their intrinsic anti-cancer properties against various cancer types including colorectal cancer (CRC). Furthermore, piperine improves the therapeutic effect of curcumin. Addressing this mutual behavior, this study combines curcumin and piperine within emulsome nanoformulations. Curcumin- (CurcuEmulsomes) and piperine-loaded emulsomes (PiperineEmulsomes) have established a uniform, stable, spherical dispersion with average diameters of 184.21 and 248.76 nm, respectively. The solid tripalmitin inner core achieved encapsulation capacities of up to 0.10 mg/ml curcumin and 0.09 mg/ml piperine content. While piperine treatment alone - in its both free and emulsome forms - showed no inhibition in the proliferation of HCT116 cells in vitro, its presence as the second drug agent enhanced curcumin's effect. Combination of 7 μM PiperineEmulsome and 25 μM CurcuEmulsome concentrations was found to be most effective with an inhibition of cell proliferation of about 50% viability. Cell cycle arrest at G2/M phase and induced apoptosis verified the improved anti-cancer characteristics of the therapy. While CurcuEmulsomes achieved a fourfold increase in Caspase 3 level, combination of treatment with PiperineEulsomes achieved a sixfold increase in the level of this apoptotic marker. Combinational treatment of HCT116 cells with CurcuEmulsomes and PiperineEmulsomes improved the anticancer activity of the compounds and highlighted the potential of the approach for further in vivo studies.

Nanocurcumin Inhibits Angiogenesis via Down-regulating hif1a/VEGF-A Signaling in Zebrafish

BACKGROUND

Curcumin has anti-inflammatory, antioxidant and anticancer properties. Despite the considerable evidence showing that curcumin is an efficacious and safe compound for multiple medicinal benefits, there are some demerits with respect to the therapeutic effectiveness of curcumin, namely, poor stability and solubility, and its role in angiogenesis in vivo is still not yet clear. More recently, the biodegradable polymer nanoparticles have been developed. This offers promise for the therapeutic effectiveness of curcumin by increasing its bioavailability, solubility and retention time.

METHODS

Here, we compared the medicinal effectiveness of curcumin and nanocurcumin (NC), and found that nanocurcumin can inhibit angiogenesis more effectively than curcumin in zebrafish. Tests of proliferation and apoptosis showed no difference between nanocurcumin-treated and wildtype embryos.

RESULTS

qPCR and in situ hybridization experiments indicated that the VEGF signaling pathway genes, vegfa, VEGF-C and flt4 were all down-regulated after nanocurcumin treatment, and vegfa over-expression rescued the vascular defective phenotype. Moreover, hif1a expression also decreased and hif1a over-expression also rescued the vascular defective phenotype but the Notch signaling pathway had no difference after nanocurcumin treatment.

CONCLUSION

These results indicate that nano curcumin inhibits angiogenesis in zebrafish by downregulating hif1a/vegfa signaling pathway. Hence, our work reveals the key role of nanocurcumin in angiogenesis in vivo.

Seaweed natural products modify the host inflammatory response via Nrf2 signaling and alter colon microbiota composition and gene expression

Seaweeds are an important component of human diets, especially in Asia and the Pacific islands, and have shown chemopreventive as well as anti-inflammatory properties. However, structural characterization and mechanistic insight of seaweed components responsible for their biological activities are lacking. We isolated cymopol and related natural products from the marine green alga Cymopolia barbata and demonstrated their function as activators of transcription factor Nrf2-mediated antioxidant response to increase the cellular antioxidant status. We probed the reactivity of the bioactivation product of cymopol, cymopol quinone, which was able to modify various cysteine residues of Nrf2's cytoplasmic repressor protein Keap1. The observed adducts are reflective of the polypharmacology at the level of natural product, due to multiple electrophilic centers, and at the amino acid level of the cysteine-rich target protein Keap1. The non-polar C. barbata extract and its major active component cymopol, reduced inflammatory gene transcription in vitro in macrophages and mouse embryonic fibroblasts in an Nrf2-dependent manner. Cymopol-containing extracts attenuated neutrophil migration in a zebrafish tail wound model. RNA-seq analysis of colonic tissues of mice exposed to non-polar extract or cymopol showed an antioxidant and anti-inflammatory response, with more pronounced effects exhibited by the extract. Cymopolia extract reduced DSS-induced colitis as measured by fecal lipocalin concentration. RNA-seq showed that mucosal-associated bacterial composition and transcriptional profile in large intestines were beneficially altered to varying degrees in mice treated with either the extract or cymopol. We conclude that seaweed-derived compounds, especially cymopol, alter Nrf2-mediated host and microbial gene expression, thereby providing polypharmacological effects.

A short review on chemical properties, stability and nano-technological advances for curcumin delivery

Introduction: Curcumin is a polyphenol found in turmeric that is derived from the rhizomes of Curcuma longa. Curcumin has received a worldwide attention due to being a major constituent of the traditional Chinese and Indian holistic systems, and due to its well-documented pharmacological effects against various diseases.Areas covered: In order to provide a better understanding of curcumin's biological activities, its chemical, structural, spectral and photophysical properties should be studied. Also, it is crucial to study the aqueous, spectral, photophysical, photochemical, and thermal stability. Such studies indicated that curcumin suffers from bioavailability problems such as low serum levels, limited tissue distribution, and excessive metabolism which all limit its therapeutic efficacy. This review summarizes different properties of curcumin, its stability, bioavailability problems, and recent nanotechnological approaches with special highlight on nanocapsules for curcumin delivery.Expert opinion: Poor bioavailability of curcumin could be overcome through recently emerging and promising nanotechnological approaches.

Small Diameter Xenogeneic Extracellular Matrix Scaffolds for Vascular Applications

Currently, despite the success of percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG) remains among the most commonly performed cardiac surgical procedures in the United States. Unfortunately, the use of autologous grafts in CABG presents a major clinical challenge as complications due to autologous vessel harvest and limited vessel availability pose a significant setback in the success rate of CABG surgeries. Acellular extracellular matrix (ECM) scaffolds derived from xenogeneic vascular tissues have the potential to overcome these challenges, as they offer unlimited availability and sufficient length to serve as "off-the-shelf" CABGs. Unfortunately, regardless of numerous efforts to produce a fully functional small diameter xenogeneic ECM scaffold, the combination of factors required to overcome all failure mechanisms in a single graft remains elusive. This article covers the major failure mechanisms of current xenogeneic small diameter vessel ECM scaffolds, and reviews the recent advances in the field to overcome these failure mechanisms and ultimately develop a small diameter ECM xenogeneic scaffold for CABG. Impact Statement Currently, the use of autologous vessel in coronary artery bypass graft (CABG) is common practice. However, the use of autologous tissue poses significant complications due to tissue harvest and limited availability. Developing an alternative vessel for use in CABG can potentially increase the success rate of CABG surgery by eliminating complications related to the use of autologous vessel. However, this development has been hindered by an array of failure mechanisms that currently have not been overcome. This article describes the currently identified failure mechanisms of small diameter vascular xenogeneic extracellular matrix scaffolds and reviews current research targeted to overcoming these failure mechanisms toward ensuring long-term graft patency.