Association of healthy and unhealthy plant-based diets with telomere length.

BACKGROUND & AIMS: Previous studies have shown that plant-rich dietary patterns, such as the Mediterranean diet, are associated with longer telomeres. However, no association has been found between vegetarian diet and telomere length. We hypothesized that the quality of plant-based diets plays an important role in telomere length. METHODS: Data were obtained from the National Health and Nutrition Examination Survey 1999-2002. Diet was assessed using a 24-h recall method. Plant-based diet quality was assessed using the overall plant-based diet index (PDI), healthy PDI (hPDI), and unhealthy PDI (uPDI). Telomere length was measured using quantitative PCR. Linear and ordinal logistic regression models were used to assess the association of PDIs with log-transformed telomere length and ordinal quintiles of telomere length in descending order, respectively. RESULTS: In both regression models, the overall PDI was not associated with telomere length. The hPDI was associated with longer telomere length [percentage change = 2.34%, 95% confidence interval (CI): 0.42%, 4.31%, Ptrend = 0.016; odds ratio (OR) = 0.81, 95% CI: 0.69, 0.95, Ptrend = 0.013]. However, uPDI was associated with shorter telomere length (percentage change = -3.17%, 95% CI: -5.65%, -0.62%, Ptrend = 0.017; OR = 1.25, 95% CI:1.03, 1.53, Ptrend = 0.014) and this inverse association was stronger in the non-Hispanic white population (Pinteraction = 0.001 in both regression models). CONCLUSIONS: A plant-based dietary pattern rich in healthy plant foods is associated with longer telomeres. However, plant-based dietary patterns rich in unhealthy plant-based foods are associated with shorter telomere lengths, especially in non-Hispanic white populations.

Effective Attenuation of Arteriosclerosis Following Lymphatic-Targeted Delivery of Hyaluronic Acid-Decorated Rapamycin Liposomes.

Background: The activation of lymphatic vessel function is the crux to resolving atherosclerosis (AS), a chronic inflammatory disease. Rapamycin (RAPA) recently has attracted considerable attention as a potent drug to induce atherosclerotic plaque attenuation. The objective of this work was to develop a ligand-decorated, RAPA-loaded liposome for lymphatic-targeted delivery of drugs to improve abnormal lymphatic structure and function, resulting in highly effective regression of atherosclerotic plaques. Methods: Hyaluronic acid-decorated, RAPA-loaded liposomes (HA-RL) were fabricated by emulsion-solvent evaporation. The average size, zeta potential, entrapment efficiency were characterized, and the stability and drug release in vitro were investigated. Furthermore, the in vitro and in vivo lymphatic targeting ability were evaluated on lymphatic endothelial cells and LDLR-/- mice, and the efficiency of this nano-system in inducing the attenuation of atherosclerotic plaques was confirmed. Results: HA-RL had a size of 100 nm, over 90% drug encapsulation efficiency, the storage stability was distinguished, demonstrating a slow release from the lipid nano-carriers. The mean retention time (MRT) and elimination half-life (t1/2ß) achieved from HA-RL were 100.27±73.08 h and 70.74±50.80 h, respectively. HA-RL acquired the most prominent efficacy of lymphatic-targeted delivery and atherosclerotic plaques attenuation, implying the successful implementation of this novel drug delivery system in vivo. Conclusion: HA-RL exhibited the most appreciable lymphatic targeting ability and best atherosclerotic plaques attenuation efficiency, opening a new paradigm and promising perspective for the treatment of arteriosclerosis.

Aptamer-modified M cell targeting liposomes for oral delivery of macromolecules.

There is an urgent demand for non-invasive and high compliance delivery systems of macromolecules for long-term therapy. However, oral administration of macromolecules is hindered by low permeability and instability in the gastrointestinal (GI) tract. Therefore, we developed a novel aptamer-modified liposomes (Apt-Lip) with M cell targeting for oral delivery of exenatide (EXT). Firstly, we optimized aptamers to M cells by Cell-SELEX and aptamer truncations. The selected aptamer T-M3 (Apt-T-M3) with high binding affinity (Kd = 176 ± 108 nM) and specificity was modified on the surface of liposomes for targeting M cells. Liposomes were formulated by microfluidics system and characterized in terms of morphology, hydrodynamic diameter, zeta potential, and the efficiency of encapsulation. In comparison with non-targeting liposomes, cell uptake in M cells was significantly enhanced by Apt-Lip. Similarly, the transport efficiency of EXT was 2-fold increase using Apt-Lip in M cells. Additionally, the transepithelial electrical resistance (TEER) of M cell monolayers is significantly reduced. In ex vivo intestinal absorption study, Apt-Lip was proved to possess significantly high intestinal absorption in Peyer's patches (PPs) and M cells-specific targeting capacity. Consequently, Apt-Lip promoted the EXT transport could base not only on M cell mediated transport, but also on enhancement of paracellular permeability. In conclusion, the present study supported Apt-Lip as a promising M cell targeted delivery system for oral delivery of macromolecules.

Self-assembled iRGD-R7-LAHP-M nanoparticle induced sufficient singlet oxygen and enhanced tumor penetration immunological therapy.

The generation of singlet oxygen (1O2) using photodynamic therapy (PDT) is limited by the hypoxia of the tumor microenvironment and the depth of external light penetration because it depends on the precise cooperation between the photosensitizers, oxygen, and light. Herein, we report a self-sufficient 1O2 nanoreactor with enhanced penetration into deep tumors for cancer therapy. Linoleic acid hydroperoxide (LAHP) is coordinated with transition metal ions (Cu2+/Fe3+) to prepare linoleic acid hydroperoxide metal complex nanoparticles (LAHP-M NPs). iRGD combined with R7 decoration endows the nanoparticles with tumor targeting and penetration ability. We show that the polypeptide carries the nanoparticles into deep tumors, and thereafter the nanoparticles are disassembled into LAHP and catalytical metal ions to produce 1O2 based on the Russell mechanism under the stimulation of acidic pH. The elevated ROS induces necrotic cell death in vitro and in vivo, and further causes immunogenic cell death (ICD). This study demonstrates the effectiveness of exploiting biochemical reactions as a spatial-temporal strategy to overcome the current limitations of photodynamic therapy.

Computer simulation and design of DNA-nanoprobe for fluorescence imaging DNA repair enzyme in living cells.

In situ imaging of DNA repair enzymes in living cells gives important insights to diagnosis and explore the formation of various diseases. Fluorescent probes have become a powerful and widely used technique for their high sensitivity and real-time capabilities, but empirical design and optimization of the corresponding probes can be blind and time-consuming. Herein, we report a strategy combining experimental studies with molecular simulation techniques for the rapid and rational design of sensitive fluorescent DNA probes for a representative DNA repair enzyme human apurinic/apyrimidinic endonuclease 1 (APE1). Extended-system Adaptive Biasing Force (eABF) was applied to study the interaction mechanism between DNA probes with respect to the enzyme, based on which a novel sensitive DNA probe was designed efficiently and economically. Product inhibition effect which significantly limited the sensitivity of existing probes was eliminated by decreasing the key interactions between DNA probe products and enzyme. Experimental mechanism studies showed the existence of intramolecular hairpin structure in DNA probes is important for the recognition of APE1 and elimination of product inhibition, which is in consistent with the simulations. The obtained fluorescent DNA nanoprobe (Nanoprobe N) showed a high sensitivity for APE1 with the detection limit as low as 0.5 U/L (∼0.018 pM), and the Nanoprobe N could effectively respond to the variation of APE1 within cells and distinguish cancer cells from normal cells. This work not only demonstrated the effectiveness of molecular simulations in probe design, but also provided a reliable platform for accurate imaging of APE1 and effectors screening at single-cell level.

Molecularly Imprinted Polymers with Enzymatic Properties Reduce Cytokine Release Syndrome.

A core-shell molecularly imprinted polymer nanoparticle with biological enzyme functional characteristics was developed by oxidative polymerization of template protein and polydopamine on the surface of protease-copper phosphate hybrid nanoflowers by molecular imprinting technology and enzyme immobilization technology. The obtained molecularly imprinted polymer showed specific binding characteristics with the template protein. It recognized and enriched the target molecules through the surface molecularly imprinted sites of the shell structure. In addition, the bound target molecules were further degraded into fragments by nanozymes with biological enzyme characteristics in the core. In this study, molecular imprinting technology and biotechnology were combined to obtain bifunctional molecularly imprinted polymer nanoparticles that can not only enrich template molecules but also degrade them into fragments. Herein, we selected interleukin 6 (IL-6), the target molecule of cytokine release syndrome (CRS), as a template molecule, and reported a molecularly imprinted polymer with degrading enzyme properties that can rapidly reduce IL-6 levels in vivo, including a molecularly imprinted layer that can recognize and bind IL-6 and nanozymes that can degrade IL-6 and deactivate it. It is used to clear the excessive secretion of IL-6 in CRS and reduce the level of IL-6 in the body to achieve the purpose of adjuvant treatment of CRS.

Tumor Microenvironment-Responsive Theranostic Nanoplatform for Guided Molecular Dynamic/Photodynamic Synergistic Therapy.

The integration of reactive oxygen species (ROS)-involved molecular dynamic therapy (MDT) and photodynamic therapy (PDT) holds great promise for enhanced anticancer effects. Herein, we report a biodegradable tumor microenvironment-responsive nanoplatform composed of sinoporphyrin sodium (SPS) photosensitizer-loaded zinc peroxide nanoparticles (SPS@ZnO2 NPs), which can enhance the action of ROS through the production of hydrogen peroxide (H2O2) and singlet oxygen (1O2) for MDT and PDT, respectively, and the depletion of glutathione (GSH). Under these conditions, SPS@ZnO2 NPs show excellent MDT/PDT synergistic therapeutic effects. We demonstrate that the SPS@ZnO2 NPs quickly degrade to H2O2 and endogenous Zn2+ in an acidic tumor environment and produce toxic 1O2 with 630 nm laser irradiation both in vitro and in vivo. Anticancer mechanistic studies show that excessive production of ROS damages lysosomes and mitochondria and induces cellular apoptosis. We show that SPS@ZnO2 NPs increase the uptake and penetration depth of photosensitizers in cells. In addition, the fluorescence of SPS is a powerful diagnostic tool for the treatment of tumors. The depletion of intracellular GSH through H2O2 production and the release of cathepsin B enhance the effectiveness of PDT. This theranostic nanoplatform provides a new avenue for tumor microenvironment-responsive and ROS-involved therapeutic strategies with synergistic enhancement of antitumor activity.

Exenatide-loaded inside-porous poly(lactic-co-glycolic acid) microspheres as a long-acting drug delivery system with improved release characteristics.

The glucagon-like peptide-1 receptor agonist exenatide (EXT) is an effective treatment for type 2 diabetes. However, this peptide has a short biological half-life and the delayed release characteristic of current formulations limit its clinical application. Herein, we prepared EXT-loaded inside-porous poly(d,l-lactic-co-glycolic acid (PLGA) microspheres with outside layers (EXT-PMS) using a W1/O/W2 emulsion method with a microfluidic technique and its fabrication and formulation conditions were systematically investigated. In vitro dissolution experiments showed that the PLGA concentration, proportion of drug and oil phase, and the number and size of pores strongly affected the release behaviors of EXT-PMS. In vitro, the optimized EXT-PMS with large internal pores exhibited rapid and stable release without a lag phase. In a rat model, subcutaneous administration of the product yielded plasma concentrations of EXT that was sustained for 30 days with low burst and no delayed-release effect. The preparation of inside-porous microspheres is lighting up the development of long-acting drug delivery systems for other drugs with favorable release characteristics.

Development of a Highly Water-Soluble Lycopene Cyclodextrin Ternary Formulation by the Integrated Experimental and Modeling Techniques.

Lycopene, the aliphatic hydrocarbon carotenoid with abundant bioactivities, has instability, extremely poor water solubility, and low oral bioavailability. The study aimed to develop a highly water-soluble and practical lycopene formulation to improve the oral bioavailability and efficiency of lycopene. Environment-friendly hot-melt extrusion (HME) technique was applied to fabricate lycopene-cyclodextrin-polyethylene glycol 6000 (PEG 6000) ternary systems, which possessed highly aqueous solubility (897.665 µg mL-1), almost 32-fold higher than that of the reported lycopene binary inclusion (27.1 ± 3.2 µg mL-1). The dissolution rate was significantly accelerated compared to pure lycopene. The molecular mechanism was further investigated by the integrated experimental and modeling tools. Molecular dynamics (MD) simulation revealed lycopene molecule was wrapped within the aggregates of hydroxypropyl-beta-cyclodextrin (HP-ß-CD) and PEG 6000 through extensive hydrogen bond interactions, which was experimentally validated by DSC, XRD, and FTIR spectrum analysis. The third component PEG 6000 facilitated the process of HME and augmented hydrogen bond interactions with HP-ß-CD. Moreover, lycopene inclusions exhibited significant antitumor activity via inhibiting cell proliferation and inducing apoptosis. The pharmacokinetic studies showed the relative bioavailability of lycopene ternary preparation was up to 313.08% and the Cmax was 4.9-fold higher than that of the marketed tablet. In conclusion, the lycopene cyclodextrin ternary formulation developed by the modified HME techniques is suitable for industrial production, while PEG 6000 plays a vital part in the multicomponent systems to increase solubility, dissolution rate, and oral bioavailability of lycopene. The combination of experimental and computational tools is able to benefit the development of multicomponent formulations accurately and effectively.

Long-term sustained release Poly(lactic-co-glycolic acid) microspheres of asenapine maleate with improved bioavailability for chronic neuropsychiatric diseases.

Schizophrenia and bipolar disorder are severe chronic neuropsychiatric diseases, affecting hundreds of millions of people worldwide. Asenapine maleate (ASM) has been demonstrated as a safe and effective therapeutic agent under twice-daily administration. However, lower compliance is observed when patients are treated with ASM, which significantly limits its application in schizophrenia and bipolar disorder. Moreover, the low bioavailability of ASM caused by first-pass metabolism and poor aqueous solubility also impairs the treatment effect. A formulation of ASM with the property of long-term sustained release and improved bioavailability can be a solution to overcome these weaknesses. In this article, we prepared ASM-loaded poly(lactic-co-glycolic acid) (ASM-PLGA) microspheres through different techniques, including emulsification-solvent evaporation (ESE), Shirasu porous glass membrane emulsification (SPG-ME), and microfluidic method. In vitro and in vivo assessments demonstrated that uniform-sized microspheres generated by the microfluidic process sustainably released ASM throughout 40-days, showing low burst release and significantly improved bioavailability. The results suggest that ASM-PLGA microspheres prepared by the microfluidic method provide an efficient strategy to enhance the drug exposure of ASM as the treatment of chronic neuropsychiatric diseases. It is also evident that this microfluidic strategy has the potential to construct with other drugs, establishing long-acting formulations.

Delivery of Platinum(IV) Prodrugs via Bi2Te3 Nanoparticles for Photothermal-Chemotherapy and Photothermal/Photoacoustic Imaging.

Combinational administration of photothermal therapy (PTT) and chemotherapy (CT) shows great potential in improving the efficiency of tumor treatment. Herein, we designed a novel nanocomposite Pt@Bi2Te3 composed of bismuth telluride (Bi2Te3) nanoparticles and platinum(IV) prodrugs (Pt) for PTT-CT combination therapy. The obtained Bi2Te3 was synthesized by a simple solvothermal method and modified by polyethylene glycol, which exhibited excellent photothermal (PT) efficiency and stability and could also serve as a bimodal bioimaging contrast agent in PT and photoacoustic (PA) imaging. In vitro experiment results showed that the nanocomposite Pt@Bi2Te3 could effectively increase the uptake of platinum in cancer cells, which could kill tumor cells through the combined effect of PTT and CT. Furthermore, combination therapy of cancer in vivo was achieved with obvious tumor-growth inhibition without inducing observed side effects. We revealed the great potential of Bi2Te3 nanocomposites in increasing therapeutic efficiency by PTT-CT therapy and PA-PT imaging.

Aqueous Extract of Whitmania Pigra Whitman Alleviates Thrombus Burden Via Sirtuin 1/NF-κB Pathway.

BACKGROUND: Whitmania pigra Whitman (W pigra), a traditional Chinese medicine, has functions of breaking stagnant and eliminating blood stasis. The aim of this study was to investigate the underlying mechanism of W pigra against deep vein thrombosis (DVT). METHODS: A rat model of DVT induced by inferior vena cava stenosis was successfully established. Rats were administered vehicle (saline solution, p.o.), three doses of W pigra aqueous extract (34.7, 104.2, or 312.5 mg crude W pigra/kg, p.o.), heparin (200 U/kg, i.v.), or clopidogrel (25 mg/kg, p.o.) once daily for 2 d. Thrombus weight and histopathological changes were examined. Blood samples were collected to determine blood cell counts, blood viscosity, blood coagulation, blood fibrinolysis, serum levels of interleukin-1ß, and tumor necrosis factor-α. Protein expressions of Sirtuin1 (SIRT1), acetylated p65 (Ace-p65), and phosphorylated p65 (p-p65) were determined by Western blot. Furthermore, SIRT1-specific inhibitor EX527 was applied to confirm the role of SIRT1 in the antithrombotic effect of W pigra. RESULTS: W pigra significantly decreased thrombus weight. W pigra had no effects on blood cell counts, whole blood viscosity, blood coagulation, blood fibrinolysis. However, it reduced tissue factor protein expression in the vein wall and thrombus. Moreover, it sharply increased SIRT1 protein expression and decreased leukocytes recruitment in the thrombus and vein wall, serum levels of interleukin-1ß and tumor necrosis factor-α, and protein expressions of Ace-p65 and p-p65. Furthermore, the antithrombotic effect of W pigra was significantly abolished by EX527. CONCLUSIONS: Aqueous extract of W pigra effectively reduced DVT burden by inhibiting inflammation via SIRT1/nuclear factor-kappa B signaling pathway.

An Aseptic One-Shot Bottom-Up Method To Produce Progesterone Nanocrystals: Controlled Size and Improved Bioavailability.

Progesterone (PG) is an essential sex hormone with a variety of important biological functions, but its insolubility leads to low bioavailability of most water-based formulations. What is more, the commercial oil-based formulations often cause severe side effects after long-term injection due to poor tissue absorption of oil. Herein, we report an aseptic bottom-up method utilizing emulsion freeze-drying technology that produces size-controllable, highly bioavailable, and water-based PG nanocrystal injection. The key factors that can determine the features of nanocrystals were investigated, including solvents, water-to-oil ratio, drug concentrations, type of surfactants, temperature in freeze-drying process, and lyoprotectants. Mechanisms of crystal growth formation process for PG nanocrystals were also analyzed theoretically. The prepared water-based PG nanocrystal suspension injection (PG/NSI) not only showed quick dissolution behaviors but also had significantly improved bioavailability in vivo. Therefore, this method can effectively control the size of nanocrystals, enhance bioavailability of insoluble drugs, and produce aseptic water-based nanocrystals that can be directly used for injection. Moreover, this method can also be used to prepare nanocrystals with the desired size under aseptic conditions for other poorly water-soluble drugs.

Hot melt extrusion of heat-sensitive and high melting point drug: Inhibit the recrystallization of the prepared amorphous drug during extrusion to improve the bioavailability.

Using tadalafil (TD) as a representative of heat-sensitive drug with high melting point and strong crystallization tendency, we observed that recrystallization of the prepared amorphous materials during extrusion can result in failure of amorphous solid dispersion (ASD) extrusion. Such recrystallization process of amorphous TD during reheating process was investigated systematically. Our results show that spray-dried amorphous TD sample is more prone to recrystallize (occurs from 150 °C) in comparison to the melt-quenched amorphous TD sample (recrystallizes from 190 °C). Poor stability of the spray-dried TD sample is likely due to an excessive amount of available surface area. Co-extruding Soluplus with spray-dried amorphous TD at 160 °C could yield ASD at 10% drug loading and crystalline solid dispersion above 20% drug loading. The method that spray drying 20% TD with 80% Soluplus and then extruding the spray-dried sample can obtain ASD at 20% drug loading at 160 °C, 142 °C lower than the melting point of TD (302 °C). More importantly, the samples prepared by such strategy exhibited a substantially improved bioavailability compared to the samples that were prepared by either spray-dried or hot-melt extruded processes.

Deep Vein Thrombosis is Modulated by Inflammation Regulated via Sirtuin 1/NF-κB Signalling Pathway in a Rat Model.

BACKGROUND: Inflammation plays an important role in thrombus formation, and Sirtuin 1 (SIRT1) negatively regulates inflammation via deacetylating nuclear factor-kappa B. However, the relationship between SIRT1-regulated inflammation and deep vein thrombosis (DVT) is still unknown. OBJECTIVE: The aim of this study was to investigate whether SIRT1 plays a critical role in inferior vena cava (IVC) stenosis-induced DVT. MATERIALS AND METHODS: Thrombus weight and histopathologic analysis of IVC were evaluated at different time points after IVC stenosis in rats. Serum levels of inflammatory cytokines and protein expressions of SIRT1, acetylated p65 (Ace-p65), phosphorylated p65 (p-p65) and tissue factor (TF) in thrombosed IVC were assessed. Besides, the effects of resveratrol (RES, a SIRT1 agonist) and EX527 (a selective SIRT1 inhibitor) on DVT were evaluated. RESULTS: Thrombus weight was increased from 1 to 3 days after IVC stenosis, and then was decreased afterwards. Leukocytes infiltration appeared and serum levels of cytokines were significantly increased in rats of IVC stenosis. SIRT1 protein expression was significantly down-regulated at 1 hour and 1 day after stenosis, while p-p65, Ace-p65 and TF protein expressions appeared a contrary trend. RES reduced thrombus weight, leukocytes infiltration, levels of tumour necrosis factor-α and interleukin-1ß and protein expressions of Ace-p65 and TF as well. Moreover, RES significantly increased the protein and messenger ribonucleic acid expressions of SIRT1, while EX527 abolished the protective effects of RES. CONCLUSION: SIRT1 activation attenuated IVC stenosis-induced DVT via anti-inflammation in rats. Therefore, SIRT1 may be a potential therapeutic target that could ameliorate DVT.

Cabazitaxel liposomes with aptamer modification enhance tumor­targeting efficacy in nude mice.

The present study investigated the feasibility of improving the tumor­targeting efficacy and decreasing the toxicity of liposomal cabazitaxel (Cab) with aptamer modification. The process involved preparing aptamer (TLS1c)­modified liposomes and studying the behavior of the liposomes in vitro and in vivo. TLS1c as an aptamer, which has high specificity for BNL 1ME A.7R.1 (MEAR) cells, was conjugated with Cab liposomes (Cab/lipo) to enhance MEAR tumor tissue targeting. Confocal laser scanning microscopy and flow cytometry analyses demonstrated that the fluorescence of the liposomes modified with the aptamer was notably stronger compared with that of the unmodified liposomes. Furthermore, the biodistribution data of the modified liposomes tested in tumor­bearing mice revealed high specificity of biotinylated TLS1c­modified Cab/lipo (BioTL­Cab/lipo) for tumor tissues. Furthermore, the modified liposomes demonstrated decreased cytotoxicity and simultaneously retained potent inhibition against tumor growth. It is likely that the specific binding of the aptamer (TLS1c) to the targeted cells (MEAR) facilitates the binding of the liposomes to the targeted cells. Therefore, BioTL­Cab/lipo may be considered as a promising delivery system to improve cell targeting and reduce drug toxicity in the treatment of cancer.

Enhancement of the apparent solubility and bioavailability of Tadalafil nanoparticles via antisolvent precipitation.

The ability to increase the bioavailability and dissolution of poorly soluble hydrophobic drugs has been a major challenge for pharmaceutical development. This study shows that the dissolution rate, apparent solubility and oral bioavailability of tadalafil (Td) can be improved by nano-sized amorphous particles prepared by using antisolvent precipitation. Acetone and an acetone-water solution (v:v, 9:1) were selected as solvents, with deionized water as the antisolvent. The antisolvent precipitation process was conducted at a constant drug concentration of 10 mg/ml, at temperatures of 5, 10 and 15 °C and at volume ratios of antisolvent to solvent (AS/S) of 5, 8 and 10. Solid dispersion was achieved by dissolving the polymer in the antisolvent prior to the precipitation and by spray drying the suspension after the antisolvent precipitation process. The selected polymers were HPMC, VA64, and PVPK30 at concentrations of 33, 100 and 300 mg per 100 ml of water (equivalent to weight ratios of drug-to-polymer of 1:3, 1:1 and 3:1, respectively). The solid dispersions were characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC) and fourier transform infrared spectroscopy (FT-IR). The improvements in the dissolution rate, equilibrium solubility, apparent solubility and bioavailability were tested and compared with unprocessed Td. Td particles in the suspension (before spray drying) were 200 nm, and the obtained Td solid dispersion had a size of approximately 5-10 µm. The XRPD, DSC and FT-IR analyses confirmed that the prepared Td particles in the solid dispersions were amorphous. The solid dispersion obtained using the optimized process conditions exhibited 8.5 times faster dissolution rates in the first minute of dissolution, 22 times greater apparent solubility at 10 min and a 3.67-fold increase in oral bioavailability than the as-received Td. The present work demonstrated that low temperature antisolvent precipitation technique has excellent potential to prepare nano-sized amorphous particles with a faster release and a higher bioavailability.

Gastric retention pellets of edaravone with enhanced oral bioavailability: Absorption mechanism, development, and in vitro/in vivo evaluation.

Absorption mechanism of edaravone (EDR) was studied to inform the preparation of gastric retention pellets with the aim to enhance its oral bioavailability. Three different models, namely, Caco-2 cells model, in situ single-pass intestinal perfusion model, and everted gut sac model in rats, were employed to characterize the gastrointestinal absorption kinetics of EDR. And it was found that passive transfer plays a vital role for the transport of EDR, and acidic condition is preferable for EDR absorption. Further, it is likely that EDR acts as a substrate for P-glycoprotein and multidrug-resistance protein. And hence, an orally available gastric retention pellets were developed accordingly. Pharmacokinetic experiments performed with rats and beagles showed that the absolute bioavailability of EDR solution and enteric-coated pellets following oral administration were 33.85% ±â€¯2.45% and 7.64% ±â€¯1.03%, indicating that stomach absorption is better than intestinal adsorption for EDR. However, the gastric retention pellets resulted in 68.96% absolute bioavailability and about 200% relative bioavailability in comparison to EDR solution, which was 9 times that of enteric-coated pellets. The present work demonstrates that gastric retention pellets has excellent potential as oral administration route for EDR.

Study of Absorption Characteristics of the Total Saponins from Radix Ilicis Pubescentis in an In Situ Single-Pass Intestinal Perfusion (SPIP) Rat Model by Using Ultra Performance Liquid Chromatography (UPLC).

In contrast to the extensively reported therapeutic activities, far less attention has been paid to the intestinal absorption of the total saponins from Radix Ilicis Pubescentis (in Chinese Mao-Dong-Qing, MDQ). This study aimed to investigate the intestinal absorption characteristics of ilexgenin A (C1), ilexsaponin A1 (C2), ilexsaponin B1 (C3), ilexsaponin B2 (C4), ilexsaponin B3 (DC1), and ilexoside O (DC2) when administrated with the total saponins from MDQ (MDQ-TS). An UPLC method for simultaneous determination of C1, C2, C3, C4, DC1, and DC2 in intestinal outflow perfusate was developed and validated. The absorption characteristics of MDQ-TS were investigated by evaluating the effects of intestinal segments, drug concentration, P-glycoprotein (P-gp) inhibitor (verapomil), endocytosis inhibitor (amantadine) and ethylene diamine tetraacetic acid (EDTA, tight junction modulator) on the intestinal transportation of MDQ-TS by using a single-pass intestinal perfusion (SPIP) rat model, and the influence of co-existing components on the intestinal transport of the six saponins was discussed. The results showed that effective apparent permeability (Papp) of C1, C2, C3, C4, and DC2 administrated in MDQ-TS form had no segment-dependent changes at low and middle dosage levels. C1, C2, C3, D4, DC1, and DC2 administrated in MDQ-TS form all exhibited excellent transmembrane permeability with Papp > 0.12 × 10-2 cm·min-1. Meanwhile, Papp and effective absorption rate constant (Ka) values for the most saponins showed concentration dependence and saturation characteristics. After combining with P-gp inhibitor of verapamil, Papp of C2, C3, and DC1 in MDQ-TS group was significantly increased up to about 2.3-fold, 1.4-fold, and 3.4-fold, respectively in comparison to that of non-verapamil added group. Verapamil was found to improve the absorption of C2, C3, and DC1, indicating the involvement of an active transport mechanism in the absorption process. Compared with the non-amantadine added group, the absorption of C1, C2, C4, DC1, and DC2 were decreased by 40%, 71%, 31%, 53%, and 100%, respectively. Papp for the six target compounds increased up to about 1.2-2.1-fold in comparison with the non-EDTA added, respectively. The gastrointestinal transport of MDQ-TS could be greatly promoted by EDTA, and inhibited by amantadine, implying that the intestinal absorption of MDQ-TS was by passive diffusion and endocytosis process. Compared with monomer administration group, the intestinal absorption of C3, C4, DC1, and DC2 was significantly improved by co-existing components in MDQ-TS, and the non-absorbable saponins of C4, DC1, and DC2 unexpectedly showed sufficient intestinal permeability with Papp > 0.12 × 10-2 cm·min-1. This suggested that compounds orally administrated in TCM extract forms displayed unique intestinal absorption characteristics different from those of monomers, and the enhancing intestinal absorption of MDQ-TS reflected a holistic and specific view of traditional Chinese medicines (TCMs).

A novel drug delivery gel of terbinafine hydrochloride with high penetration for external use.

CONTEXT: Terbinafine hydrochloride is an antifungal drug for onychomycosis. Poor permeability of its external preparation leads to poor curative effect. Transfersomes, also known as flexible liposome, could improve transmission of drug for local external use. Terbinafine hydrochloride-loaded liposome is expected to become a breakthrough on the treatment of onychomycosis. OBJECTIVE: This study is aimed to prepare high skin penetration terbinafine hydrochloride transfersomes with high encapsulation efficiency, appropriate drug loading and good stability. MATERIALS AND METHODS: Taking entrapment efficiency as the main indicator, the formulations and the processes of preparation were investigated. Transfersomes with different surfactants were prepared in the optimization processes, and the formulations were optimized through the transdermal test in vitro. As a result, a gel contained transfersomes was obtained with a brief evaluation. Its pharmacokinetic properties of going through the skin were studied by using the micro dialysis technology and liquid chromatography-mass spectrometry to assay the penetration behavior of terbinafine. RESULTS: Mean particle size of the terbinafine hydrochloride transfersomes was 69.6 ± 1.23 nm, and the entrapment efficiency was 95.4% ± 0.51. The content of the gel was 4.45 ± 0.15 mg/g. The accumulated permeation of the transfersomes gel in 12 h was 88.52 ± 4.06 µg cm-2 and the intracutaneous drug detention was 94.38 ± 5.26 µg cm-2. The results of pharmacokinetic studies showed the Cmax and area under the curve (AUC) were apparently higher than the commercial cream. DISCUSSION AND CONCLUSION: The terbinafine hydrochloride transfersomes was highly absorbed by the skin. The absorption rate was significantly higher than that of the commercial cream either in the transdermal test in vitro or in the pharmacokinetic studies in vivo.