Anti-Inflammatory Activity of 1,6,7-Trihydroxy-2-(1,1-dimethyl-2-propenyl)-3-methoxyxanthone Isolated from Cudrania tricuspidata via NF-κB, MAPK, and HO-1 Signaling Pathways in Lipopolysaccharide-Stimulated RAW 264.7 and BV2 Cells.

Neuroinflammation activated by microglia affects inflammatory pain development. This study aimed to explore the anti-inflammatory properties and mechanisms of 1,6,7-trihydroxy-2-(1,1-dimethyl-2-propenyl)-3-methoxyxanthone (THMX) from Cudrania tricuspidata in microglia activation-mediated inflammatory pain. In RAW 264.7 and BV2 cells, THMX has been shown to reduce lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and pro-inflammatory mediators and cytokines, including nitric oxide (NO), prostaglandin (PG) E2, interleukin (IL)-6, and tumor necrosis factor alpha (TNF-α). THMX also decreased LPS-induced phosphorylation of mitogen-activated protein kinase (MAPK) and the activation of p65 nuclear factor kappa B (NF-κB). Interestingly, THMX also activated heme oxygenase (HO)-1 expression. These findings suggest that THMX is a promising biologically active compound against inflammation through preventing MAPKs and NF-ĸB and activating HO-1 signaling pathways.

Practical Manipulation for the Preparation of Mesoporous Silica Nanoparticles for Drug Delivery Vehicles.

BACKGROUND: Optimization of MSNs is the most important process for efficient and safe drug delivery systems. OBJECTIVE: In this study, the physicochemical properties of MSNs were evaluated using various compositions of individual reagents. METHODS: MSNs were synthesized according to a modified Stöber method. The physicochemical properties of MSNs were evaluated. Spherical uniform particles were observed in the scanning electron microscope (SEM) and transmission electron microscopy (TEM) image and the meso-structure of MSNs was confirmed. The amorphous and specific hexagonal structure of MSNs was confirmed through Xray diffraction (XRD) and SAXRD. RESULTS: The particle size and surface area according to changes in amounts of reagents ranged from 34.5 ± 2.3 to 216.0 ± 17.1 nm and from 549.79 to 1154.26 m2/g, respectively. A linear relationship was found between the surface area of MSNs and the adsorption rate of methylene blue (MB). MSNs exhibited no apparent cytotoxic effect on Caco-2 cell up to 200 µg/mL. The amounts of tetramethyl ammonium silicate and tetraethyl ortho silicate (TEOS), NaOH, and hexadecyl trimethyl ammonium bromide (CTAB) were adjusted to control the particle size and surface area of MSNs, and it was found that the amounts of synthetic reagents affected the physicochemical properties such as particle size and surface area of MSNs. MSNs with a large surface area adsorbed a large amount of MB. CONCLUSION: These results indicated that drug adsorption is related to the surface area of MSNs. MSNs did not show cytotoxicity to Caco-2 cells. MSNs may be a promising nanomaterial that could be applied as a carrier for various drugs.

Development and Evaluation of Tannic Acid-Coated Nanosuspension for Enhancing Oral Bioavailability of Curcumin.

Curcumin (CUR) has been used in the treatment of various diseases such as cough, fever, skin disease, and infection because of various biological benefits such as anti-inflammatory, antiviral, antibacterial, and antitumor activity. However, CUR is a BCS class 4 group and has a limitation of low bioavailability due to low solubility and permeability. Therefore, the purpose of this study is to prepare a nanosuspension (NSP) loaded with CUR (CUR-NSP) using a statistical design approach to improve the oral bioavailability of CUR, and then to develop CUR-NSP coated with tannic acid to increase the mucoadhesion in the GI tract. Firstly, the optimized CUR-NSP, composed of sodium dodecyl sulfate (SDS) and polyvinylpyrrolidone/vinyl acetate (PVP/VA), was modified with tannic acid (TA). The particle size and polydispersity index of the formulation measured by laser scattering analyzer were 127.7 ± 1.3 nm and 0.227 ± 0.010, respectively. In addition, the precipitation in distilled water (DW) was 1.52 ± 0.58%. Using a differential scanning calorimeter and X-ray diffraction analysis, the stable amorphous form of CUR was confirmed in the formulation, and it was confirmed that CUR-NSP formulation was coated with TA through a Fourier transform-infrared spectroscopy. In the mucoadhesion assay using the turbidity, it was confirmed that TA-CUR-NSP had higher affinity for mucus than CUR-NSP under all pH conditions. This means that the absorption of CUR can be improved by increasing the retention time in the GI tract of the formulation. In addition, the drug release profile showed more than 80% release, and in the cellular uptake study, the absorption of the formulation (TA-CUR-NSP) containing TA acting as an inhibitor of P-gp was increased by 1.6-fold. In the evaluation of antioxidant activity, the SOD activity of TA-CUR-NSP was remarkably high due to TA, which improves cellular uptake and has antioxidant activity. In the pharmacokinetic evaluation, the maximum drug plasma concentration of the TA-coated NSP formulation was 7.2-fold higher than that of the pure drug. In all experiments, it was confirmed that the TA-CUR-NSP is a promising approach to overcome the low oral bioavailability of CUR.

Optimization of Mesoporous Silica Nanoparticles through Statistical Design of Experiment and the Application for the Anticancer Drug.

The synthesis process or composition of mesoporous silica nanoparticles (MSNs) affects the physicochemical properties. Using these properties, MSNs were synthesized through the Box-Behnken design (BBD) among statistical experimental methods. The effect of the amounts of synthetic reagents, hexadecyl triethyl ammonium bromide (CTAB), tetraethyl orthosilicate (TEOS), and 2 N sodium hydroxide (NaOH), was studied using the reaction surface design. Surface area, particle size, and zeta potential were set as response values. The physicochemical properties of the optimized MSNs were evaluated, and the effect as a drug delivery system was evaluated by loading doxorubicin hydrochloride (DOX). Nano-sized MSNs were successfully prepared with 0.617 g of CTAB, 8.417 mL of TEOS, and 2.726 mL of 2 N NaOH and showed excellent physicochemical properties. The optimized MSNs showed negligible toxicity in MCF-7 cells. The drug release profile from DOX-loaded MSNs (MSN@DOX) showed an increased rate of release with decreasing pH of the medium, with the release profile sustained for 48 h. In the cytotoxicity test, the sustained drug release mechanism of MSN@DOX was confirmed. This study proposed a new statistical approach to the synthesis of MSNs.

Surface modification of paclitaxel-loaded liposomes using d-α-tocopheryl polyethylene glycol 1000 succinate: Enhanced cellular uptake and cytotoxicity in multidrug resistant breast cancer cells.

Liposomes can achieve a controlled release and an improved bioavailability of water- insoluble drug with minimized side effects. Paclitaxel is an efficient anticancer drug for the treatment of various cancers. However, paclitaxel has a solubility of 0.5 mg/L in water and a low bioavailability of 6.5%. Moreover, paclitaxel is a substrate for p-glycoprotein, which shows a decreased accumulation of drug within the cancer cell expressed by a p-glycoprotein. Therefore, the purpose of this study is to prepare a paclitaxel-loaded liposome and evaluate the effect of d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) as an inhibitor of p-glycoprotein on the paclitaxel-loaded liposome. The paclitaxel-loaded liposome and TPGS coated paclitaxel-loaded liposome had spherical vesicles, with mean particle size 184.9 ±â€¯18.45 nm with PDI 0.324 ±â€¯0.018 and 282.6 ±â€¯20.41 nm with PDI 0.269 ±â€¯0.013, respectively. Paclitaxel-loaded liposome and TPGS coated paclitaxel-loaded liposome showed a controlled and sustained release of PTX over 72 h. The cellular uptake of paclitaxel from TPGS coated paclitaxel-loaded liposome was a 3.56-fold increase for 2 h and 5.75-fold increase for 4 h compared to that from paclitaxel-loaded liposome in MCF-7/ADR cells, resulting in improved cytotoxicity against MCF-7/ADR cells. Western blot assay revealed the P-gp inhibitory effect of TPGS-coated PTX-liposome. In conclusion, TPGS coated liposome with a sustained releasing capability and the inhibitory effect of p-glycoprotein may be a promising carrier for future applications in cancer therapy.

Sustained Cytotoxicity of Wogonin on Breast Cancer Cells by Encapsulation in Solid Lipid Nanoparticles.

While wogonin has been known to have cytotoxicity against various cancer cells, its bioavailability and cytotoxicity are low due to its low water solubility. Therefore, wogonin-loaded solid lipid nanoparticles were fabricated using a hot-melted evaporation technique. The highest solubility of wogonin was observed in stearic acid. Hence, wogonin-loaded solid lipid nanoparticles were composed of stearic acid as the lipid matrix. The physicochemical properties of the wogonin-loaded solid lipid nanoparticles were evaluated by dynamic laser scattering and scanning electron microscopy. The wogonin-loaded solid lipid nanoparticles exhibited sustained and controlled release up to 72 h. In addition, it was observed that the wogonin-loaded solid lipid nanoparticles exhibited enhanced cytotoxicity and inhibited poly (ADP-ribose) polymerase in MCF-7 breast cancer cells. Overall, the results indicate that wogonin-loaded solid lipid nanoparticles could be an efficient delivery system for the treatment of breast cancer.

Sustained-releasing hollow microparticles with dual-anticancer drugs elicit greater shrinkage of tumor spheroids.

Polymeric particulate delivery systems are vastly explored for the delivery of chemotherapeutic agents. However, the preparation of polymeric particulate systems with the capability of providing sustained release of two or more drugs is still a challenge. Herein, poly (D, L-lactic-co-glycolic acid, 50:50) hollow microparticles co-loaded with doxorubicin and paclitaxel were developed through double-emulsion solvent evaporation technique. Hollow microparticles were formed through the addition of an osmolyte into the fabrication process. The benefits of hollow over solid microparticles were found to be higher encapsulation efficiency and a more rapid drug release rate. Further modification of the hollow microparticles was accomplished through the introduction of methyl-ß-cyclodextrin. With this, a higher encapsulation efficiency of both drugs and an enhanced cumulative release were achieved. Spheroid study further demonstrated that the controlled release of the drugs from the methyl-ß-cyclodextrin -loaded hollow microparticles exhibited enhanced tumor regressions of MCF-7 tumor spheroids. Such hollow dual-drug-loaded hollow microparticles with sustained releasing capabilities may have a potential for future applications in cancer therapy.

Surface modification of solid lipid nanoparticles for oral delivery of curcumin: Improvement of bioavailability through enhanced cellular uptake, and lymphatic uptake.

Curcumin has been reported to exhibit potent anticancer effects. However, poor solubility, bioavailability and stability of curcumin limit its in vivo efficacy for the cancer treatment. Solid lipid nanoparticles (SLN) are a promising delivery system for the enhancement of bioavailability of hydrophobic drugs. However, burst release of drug from SLN in acidic environment limits its usage as oral delivery system. Hence, we prepared N-carboxymethyl chitosan (NCC) coated curcumin-loaded SLN (NCC-SLN) to inhibit the rapid release of curcumin in acidic environment and enhance the bioavailability. The NCC-SLN exhibited suppressed burst release in simulated gastric fluid while sustained release was observed in simulated intestinal fluid. Furthermore, NCC-SLN exhibited increased cytotoxicity and cellular uptake on MCF-7 cells. The lymphatic uptake and oral bioavailability of NCC-SLN were found to be 6.3-fold and 9.5-fold higher than that of curcumin solution, respectively. These results suggest that NCC-SLN could be an efficient oral delivery system for curcumin.

A multifunctional lipid nanoparticle for co-delivery of paclitaxel and curcumin for targeted delivery and enhanced cytotoxicity in multidrug resistant breast cancer cells.

The objective of the work was to develop a multifunctional nanomedicine based on a folate-conjugated lipid nanoparticles loaded with paclitaxel and curcumin. The novel system combines therapeutic advantageous of efficient targeted delivery via folate and timed-release of curcumin and paclitaxel via 2-hydroxypropyl-ß-cyclodextrin, thereby overcoming multidrug resistance in breast cancer cells (MCF-7/ADR). The faster release of curcumin from the folate-conjugated curcumin and paclitaxel-loaded lipid nanoparticles enables sufficient p-glycoprotein inhibition, which allows increased cellular uptake and cytotoxicity of paclitaxel. In western blot assay, curcumin can efficiently inhibit the expression of p-glycoprotein, conformed the enhancement of cytotoxicity by paclitaxel. Furthermore, folate-conjugated curcumin and paclitaxel-loaded lipid nanoparticles exhibited increased uptake of paclitaxel and curcumin into MCF-7/ADR cells through the folate receptor-mediated internalization. Taken together, these results indicate that folate-conjugated curcumin and paclitaxel-loaded lipid nanoparticles enables the enhanced, folate-targeted delivery of multiple anticancer drugs by inhibiting the multi-drug resistance efficiently, which may also serve as a useful nano-system for co-delivery of other anticancer drugs.

Stability of paclitaxel-loaded solid lipid nanoparticles in the presence of 2-hydoxypropyl-ß-cyclodextrin.

Paclitaxel (PTX)-loaded solid lipid nanoparticles without hydroxyl-ß-cyclodextrin (PS) or with hydroxypropyl-ß-cyclodextrin (PSC) were prepared by hot-melted sonication. Biocompatible and biodegradable stearic acid was used to produce the solid matrix. The stability of PS and PSC was assessed at different temperatures. Drug stability, as assessed by encapsulation efficiency (EE; %), particle size, and the polydispersity index (PDI), was examined and in vitro release of PTX from PS or PSC for up to 180 days was assessed. After 180 days of storage at 25 °C, no significant change in particle size, PDI, or EE of PS or PSC was observed. PS and PSC displayed similar sustained PTX release patterns. The particle size, PDI, EE, PTX release profile, and cytotoxicity of PS changed significantly with increasing incubation time, whereas those of PSC showed no significant change, when samples were stored at 40 ± 2 °C. PSC was more stable than PS in plasma with regard to particle size and PDI. These results demonstrate that PSC could be a promising formulation to increase drug stability.

Modification of paclitaxel-loaded solid lipid nanoparticles with 2-hydroxypropyl-ß-cyclodextrin enhances absorption and reduces nephrotoxicity associated with intravenous injection.

BACKGROUND: Paclitaxel (PTX) solid lipid nanoparticles (SLNs) modified with 2-hydroxypropyl-ß-cyclodextrin (HPCD) were evaluated for their ability to enhance PTX absorption and reduce the nephrotoxicity accompanying intravenous administration. METHODS: PTX-loaded SLNs (PS) and PTX-loaded SLNs modified using HPCD (PSC) were prepared by hot-melted sonication. The anticancer activity of PSC was evaluated in MCF-7 cells, and confocal microscopy was used to quantify the cellular uptake. The pharmacokinetic profiles of PTX released from PSC after intravenous administration were studied in rats. Furthermore, kidney toxicity was determined by measuring the kidney size and plasma creatinine level. RESULTS: PSC were successfully prepared by hot-melted sonication and had smaller diameters than PS. PSC exhibited improved anticancer activity and cellular uptake in MCF-7 cells. Furthermore, PSC showed higher bioavailability in rats after intravenous administration than PTX solution; however, no significant differences in kidney toxicity were observed. CONCLUSION: Based on these results, PSC could be considered as a potential therapeutic PTX delivery system for breast cancer with low renal toxicity.

Controlled release and reversal of multidrug resistance by co-encapsulation of paclitaxel and verapamil in solid lipid nanoparticles.

Paclitaxel (PTX) has been used in the treatment of wide range of cancers but its entry into cancer cell is restricted by p-glycoprotein (p-gp). Also, it was reported that verapamil (VP) could inhibit p-gp efflux. Hence, three kinds of solid lipid nanoparticles (SLN) such as PVS (PTX and VP co-loaded SLN), PSV (PTX loaded SLN, later added VP) and PVSV (PTX and VP co-loaded SLN, later added VP) were prepared to overcome MDR by combination of PTX and VP. PVS was the SLN loaded with both PTX and VP at the same time. PSV was the SLN loaded with PTX and then modified with VP - complexed hydroxypropyl-ß-cylcodextrin (HPCD). Finally, PVSV was the SLN loaded with PTX and half of VP at the same time subsequently, modified with half of VP - complexed HPCD. The physicochemical characterizations of PVS, PSV or PVSV such as particle size, zeta potential, encapsulation efficiency or in vitro PTX release were examined. PVSV showed that release of VP was higher than PTX solution in first 15h and sustained release of both VP and PTX. PVSV showed significantly higher cytotoxicity and cellular uptake than that of the PTX solution in MCF-7/ADR resistant cells. Furthermore, PVSV significantly down regulated the expression of p-gp than the PTX solution in MCF-7/ADR resistant cells. Based on these findings, this study indicated that the PVSV exhibited great potential for breast cancer therapy.

2-Hydroxypropyl-ß-cyclodextrin-modified SLN of paclitaxel for overcoming p-glycoprotein function in multidrug-resistant breast cancer cells.

OBJECTIVES: This study aimed to evaluate the potential of solid lipid nanoparticles (SLNs) of paclitaxel (PTX) modified with a 2-hydroxypropyl-ß-cyclodextrin system to enhance cellular accumulation of PTX into p-glycoprotein (p-gp)-expressing cells. METHODS: The PTX-loaded-SLNs consisted of lipid (stearic acid) and surfactants (lecithin and poloxamer 188) and were then modified with 2-hydroxypropyl-ß-cyclodextrin by a sonication method. KEY FINDINGS: In terms of cytotoxicity, PTX-loaded SLNs modified with 2-hydroxypropyl-ß-cyclodextrin showed higher cytotoxicity than other formulations. In particular, the cellular uptake of PTX from PTX-loaded SLNs modified with 2-hydroxypropyl-ß-cyclodextrin was about 5.8- and 1.5-fold higher than that from PTX solution and unmodified PTX-loaded SLNs in MCF-7/ADR cells, respectively. After a 4-h incubation, clear fluorescence images inside cells were observed over time. When PTX-loaded SLNs modified with 2-hydroxypropyl-ß-cyclodextrin were incubated with MCF-7/ADR cells for 4 h, cellular uptake of PTX increased 1.7-fold versus that of PTX in the presence of verapamil. CONCLUSIONS: These results suggest that optimized SLNs modified with 2-hydroxypropyl-ß-cyclodextrin may have potential as an oral drug delivery system for PTX.

Solid lipid nanoparticles of paclitaxel strengthened by hydroxypropyl-ß-cyclodextrin as an oral delivery system.

The objective of this study was to evaluate the potential of surface-modified paclitaxel (PTX)-incorporated solid lipid nanoparticles with hydroxypropyl-ß-cyclodextrin (smPSH). The smPSH released 89.70 ± 3.99% of its entrapped PTX within 24 h when placed in dissolution medium containing sodium lauryl sulfate. The cellular uptake of PTX from smPSH in Caco-2 cells was 5.3-fold increased compared to a PTX solution based on a Taxol formulation. Moreover, smPSH showed an increased cytotoxicity compared to PTX solution. In addition, AUC (5.43 µg•h/ml) and Cmax (1.44 µg/ml) of smPSH were higher than those (1.81 µg•h/ml and 0.73 µg/ml) of PTX solution. The drug concentration of smPSH (11.12 ± 4.45 ng/mg of lymph tissue) in lymph nodes was higher than that of the PTX solution (0.89 ± 0.75 ng/mg of lymph tissue), suggesting that more PTX was transported to the lymphatic vessels in the form of smPSH. In conclusion, smPSH have a potential as an alternative delivery system for oral administration of PTX.

Surface-modified gemcitabine with mucoadhesive polymer for oral delivery.

Gemcitabine microparticles were prepared using chitosan, polyethylene oxide or carbopol as the mucoadhesive polymer and eudragit L100-55 as the enteric polymer by a double emulsion method. The particle size and zeta potential changed from 1338.3 ± 254.1 nm to 2459.4 ± 103.6 nm and -5.16 ± 1.62 mV to 2.84 ± 0.65 mV, respectively, with increasing chitosan to gemcitabine weight ratio from 0.25 to 1. The gemcitabine-loaded microparticles without mucoadhesive polymer (F50) showed the particle size and zeta potential of 671.3 ± 58.3 nm and - 16.7 ± 1.82 mV, respectively. The cellular uptake of gemcitabine into Caco-2 cells from gemcitabine-loaded microparticles with chitosan increased with increasing incubation time in Caco-2 cells compared to that of gemcitabine-loaded microparticles with polyethylene oxide or carbopol, suggesting that chitosan might be the optimal mucoadhesive polymer. Gemcitabine microparticles will be tested to identify whether the oral absorption could be increased in the future.