Optimization of the process variables of tilianin-loaded composite phospholipid liposomes based on response surface-central composite design and pharmacokinetic study

Preparation and Characterization of Novel Polyelectrolyte Liposomes Using Chitosan Succinate Layered over Chitosomes: A Potential Strategy for Colon Cancer Treatment

Chitosan succinate is distinguished by its ability to shield the loaded drug from the acidic environment, localize and keep the drug at the colon site, and release the drug over an extended time at basic pH. The current study attempts to develop polyelectrolyte liposomes (PEL), using chitosan and chitosan succinate (CSSC), as a carrier for liposomal-assisted colon target delivery of 5 fluorouracil (5FU). The central composite design was used to obtain an optimized formulation of 5FU-chitosomes. The chitosan-coated liposomes (chitosomes) were prepared by thin lipid film hydration technique. After that, the optimized formulation was coated with CSSC, which has several carboxylic (COOH) groups that produce an anionic charge that interacts with the cation NH2 in chitosan. The prepared 5FU-chitosomes formulations were evaluated for entrapment efficiency % (EE%), particle size, and in vitro drug release. The optimized 5FU-chitosomes formulation was examined for particle size, zeta potential, in vitro release, and mucoadhesive properties in comparison with the equivalent 5FU-liposomes and 5FU-PEL. The prepared 5FU-chitosomes exhibited high EE%, small particle size, low polydispersity index, and prolonged drug release. PEL significantly limited the drug release at acidic pH due to the deprotonation of carboxylate ions in CSSC, which resulted in strong repulsive forces, significant swelling, and prolonged drug release. According to a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, PEL treatment significantly decreased the viability of HT-29 cells. When compared to 5FU-liposome and 5FU-chitosome, the in vivo pharmacokinetics characteristics of 5FU-PEL significantly (p < 0.05) improved. The findings show that PEL enhances 5FU permeability, which permits high drug concentrations to enter cells and inhibits the growth of colon cancer cells. Based on the current research, PEL may be used as a liposomal-assisted colon-specific delivery.

Improving oral bioavailability of medicinal herbal compounds through lipid-based formulations - A Scoping Review

BACKGROUND

Although numerous medicinal herbal compounds demonstrate promising therapeutic potential, their clinical application is often limited by their poor oral bioavailability. To circumvent this barrier, various lipid-based herbal formulations have been developed and trialled with promising experimental results.

PURPOSE

This scoping review aims to describe the effect of lipid-based formulations on the oral bioavailability of herbal compounds.

METHODS

A systematic search was conducted across three electronic databases (Medline, Embase and Cochrane Library) between January 2010 and January 2021 to identify relevant studies. The articles were rigorously screened for eligibility. Data from eligible studies were then extracted and collated for synthesis and descriptive analysis using Covidence.

RESULTS

A total of 109 studies were included in the present review: 105 animal studies and four clinical trials. Among the formulations investigated, 50% were emulsions, 34% lipid particulate systems, 12% vesicular systems, and 4% were other types of lipid-based formulations. Within the emulsion system classification, self-emulsifying drug delivery systems were observed to produce the best improvements in oral bioavailability, followed by mixed micellar formulations. The introduction of composite lipid-based formulations and the use of uncommon surfactants such as sodium oleate in emulsion preparation was shown to consistently enhance the bioavailability of herbal compounds with poor oral absorption. Interestingly, the lipid-based formulations of magnesium lithospermate B and Pulsatilla chinensis produced an absolute bioavailability greater than 100% indicating the possibility of prolonged systemic circulation. With respect to chemical conjugation, D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) was the most frequently used and significantly improved the bioavailability of its phytoconstituents.

CONCLUSION

Our findings suggest that there is no distinct lipid-based formulation superior to the other. Bioavailability improvements were largely dependent on the nature of the phytoconstituents. This scoping review, however, provided a detailed summary of the most up-to-date evidence on phytoconstituents formulated into lipid preparations and their oral bioavailability. We conclude that a systematic review and meta-analysis between bioavailability improvements of individual phytoconstituents (such as kaempferol, morin and myricetin) in various lipid-based formulations will provide a more detailed association. Such a review will be highly beneficial for both researchers and herbal manufacturers.

Preparation, characterization, and pharmacodynamic study on deep second degree burns of total flavonoids composite phospholipids liposome gel of Oxytropis falcata Bunge

Wound healing is the treatment problem after deep second degree (II°) burns. The p38 mitogen-activated protein kinase (p38 MAPK) and nuclear factor-κB/inhibitory factor-κB (NF-κB/IκB) signal pathways play significant role in angiogenesis and wound repair after burns.This study aimed to investigate the preparation, characterization and pharmacodynamics of the total flavonoids composite phospholipids liposome of Oxytropis falcata Bunge (TFOFB-CPL) on deep II° burns to research its biological activity and underlying mechanism. The TFOFB-CPL was prepared by thin-film dispersion method and the preparation process was optimized via central composite design. The TFOFB-CPL was then characterized by using particle size, polydispersity indexes (PDIs), zeta potential, encapsulation efficiency (EE) and morphology. Moerover, in vitro transdermal test and in vivo pharmacodynamic study included wound healing rate, hematoxylin-eosin (HE) staining, masson staning, western blotting and RT-PCR. The results showed that the therapeutic effects of TFOFB-CPL gel on deep II° burns, especially during wound healing were significant. TFOFB-CPL gel has a sustained-release effect during the treatment of deep II° burns with forming drug depot in the dermis layer. The wound healing rate of TFOFB-CPL gel group was near positive group and better than the other groups. TFOFB-CPL gel could promote the growth of epidermis, skin appendages, fibrovascular and collagen fibers, and had obvious anti-inflammatory effects. Moreover, TFOFB-CPL gel inhibited the activation of p38MAPK and the degradation of IκBα, and promoted the neonatal wounds during the early stage. Therefore, TFOFB-CPL gel could be considered as a novel preparation for treating deep II° burns.

Development of curcumin-loaded composite phospholipid ethosomes for enhanced skin permeability and vesicle stability

Ethosomes are widely applied as the carriers for the transdermal delivery of hydrophobic and hydrophilic drugs. Herein, curcumin-loaded ethosomes (CE) with different phospholipid composition were formulated and thoroughly compared. A significant interaction between the unsaturated phosphatidylcholine (PC) and saturated hydrogenated phosphatidylcholine (HPC) was found by molecular simulation and differential scanning calorimetry (DSC), which led to the reduction of PC peroxidation with the presence of HPC. Subsequently, the composite phospholipid ethosomes containing curcumin were prepared for the first time to evaluate their properties in comparison with the conventional ethosomes composed of PC (CE-P) or HPC (CE-H). CE with PC/HPC ratio of 1:1 (CE-P1H1) with the best vesicle stability and flexibility significantly decreased the uptake by HaCaT cells compared to CE-H and free curcumin, indicating reduced skin cell toxicity. Compared with free curcumin, CE-P1H1 had the highest transdermal efficiency (p < 0.001), followed by CE-P (p < 0.05), partly due to the fact that CE-P1H1 could disturb lipid domain of stratum corneum (SC). Moreover, CE-P1H1 was found to promote curcumin for deep penetration of the skin via the hair follicles route. Our study has shown that using composite phospholipid ethosomes as lipid vesicular carriers could enhance transdermal penetration of drugs and increase in the vesicle stability.

Novel pH-Sensitive Urushiol-Loaded Polymeric Micelles for Enhanced Anticancer Activity

Purpose

The aim of this study was to develop a means of improving the bioavailability and anticancer activity of urushiol by developing an urushiol-loaded novel tumor-targeted micelle delivery system based on amphiphilic block copolymer poly(ethylene glycol)-b-poly-(β-amino ester) (mPEG-PBAE).

Materials and Methods

We synthesized four different mPEG-PBAE copolymers using mPEG-NH₂ with different molecular weights or hydrophobicity levels. Of these, we selected the mPEG₅₀₀₀-PBAE-C₁₂ polymer and used it to develop an optimized means of preparing urushiol-loaded micelles. Response surface methodology was used to optimize this formulation process. The micellar properties, including particle size, pH sensitivity, drug release dynamics, and critical micelle concentrations, were characterized. We further used the MCF-7 human breast cancer cell line to explore the cytotoxicity of these micelles in vitro and assessed their pharmacokinetics, tissue distribution, and antitumor activity in vivo.

Results

The resulting micelles had a mean particle size of 160.1 nm, a DL value of 23.45%, and an EE value of 80.68%. These micelles were found to release their contents in a pH-sensitive manner in vitro, with drug release being significantly accelerated at pH 5.0 (98.74% in 72 h) without any associated burst release. We found that urushiol-loaded micelles were significantly better at inducing MCF-7 cell cytotoxicity compared with free urushiol, with an IC₅₀ of 1.21 mg/L. When these micelles were administered to tumor model animals in vivo, pharmacokinetic analysis revealed that the total AUC and MRT of these micelles were 2.28- and 2.53-fold higher than that of free urushiol, respectively. Tissue distribution analyses further revealed these micelles to mediate significantly enhanced tumor urushiol accumulation.

Conclusion

The pH-responsive urushiol-loaded micelles described in this study may be ideally suited for clinical use for the treatment of breast cancer.

Tilianin Extracted From Dracocephalum moldavica L. Induces Intrinsic Apoptosis and Drives Inflammatory Microenvironment Response on Pharyngeal Squamous Carcinoma Cells via Regulating TLR4 Signaling Pathways

Human pharyngeal squamous cell carcinoma is highly invasive and proliferative, and exhibits an extremely low 5-year survival rate due to poor understanding of the underlying pathogenic mechanisms, and lack of efficient treatment. It has been shown that the immunosuppressive microenvironment created by tumor cells impairs the immune response against tumor progression, thereby affecting the prognosis for tumor patients. Thus, to improve therapeutic efficacy, it is critical to identify novel drugs with immunoinflammatory modulatory properties to treat tumor immune evasion. Tilianin, the main ingredient of total flavonoids extracted from Dracocephalum moldavica L., has multiple biological functions, including cardiovascular protective effects, anti-tumor effects, and anti-inflammatory effects. In the present study, the suppressive effects of tilianin on human pharyngeal squamous cell carcinoma were investigated and the underlying mechanisms in regulating the tumor immunosuppressive microenvironment were explored. The cytotoxicity of tilianin on FaDu cells was determined by CCK-8 and clone formation assays. Moreover, the levels of toll-like receptor 4 (TLR4) signaling transduction and apoptotic pathways were determined by immunocytochemical, biochemical, and molecular biological technologies. In addition, the maturation of dendritic cells (DCs) that were co-cultured in supernatant of FaDu cells was evaluated by flow cytometry to investigate alterations in immune system function. For mechanistic exploration, TLR4 siRNA, p38 siRNA, c-Jun N-terminal kinase (JNK) siRNA, and p65 siRNA were used as loss-of-function target evaluation of tilianin therapy. Combined, these results showed that tilianin treatment increased cytotoxicity as well as the apoptotic population of FaDu cells in a dose-dependent manner. Furthermore, tilianin treatment decreased the level of anti-apoptotic markers Bcl-2 and Bcl-xL, increased the level of apoptotic factors Bad and Bax, and stimulated cytochrome c release, caspase-3 and poly ADP ribose polymerase (PARP) activation in FaDu cells. Furthermore, our findings indicated that tilianin treatment activated TLR4/p38/JNK/NF-κB signaling pathways and increased the release of inflammatory cytokines. This promoted the maturation of DCs to enhance immune system function in the tumor microenvironment. Moreover, the effects of tilianin on immune system function were abolished by TLR4 siRNA and p65 siRNA. In conclusion, these findings suggested that tilianin may be of immunotherapeutic value for inhibiting human pharyngeal squamous cell carcinoma.

PHBV/PLGA nanoparticles for enhanced delivery of 5-fluorouracil as promising treatment of colon cancer

5-Fluorouracil (5-FU) is one of the most widely used agents in the first-line chemotherapy for colon cancer. However, clinical use of 5-FU is limited because of the low efficacy of drug uptake and systemic toxic effects. Therefore, there is a critical need to find better drug delivery systems in order to improve the efficacy of the drug. In the present study, we have developed a novel combination drug delivery system based on PHBV/PLGA NPs for delivery of 5-FU to cancer cells. NPs were prepared by the double emulsion method and their optimization of preparation was evaluated using Box-Behnken design (BBD) of response surface methodology (RSM). 5-FU loaded NPs were characterized by scanning electron microscope (SEM), differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), and Fourier transformed infra-red spectroscopy (FT-IR). SEM image implied that NPs were spherical in shape and the results of DSC, TGA, and FT-IR suggest that 5-FU was encapsulated into NPs. The obtained results revealed that 5-FU loaded PHBV/PLGA NPs induced significant higher cell death at concentration much lower than free 5-FU. Results of hemolysis assay indicated that the NPs were hemo-compatible. In vivo anti-tumor studies showed that 5-FU loaded NPs reduced tumor volume significantly in comparison with free 5-FU. As the first example of using PHBV/PLGA as nano-drug delivery system with enhanced anti-tumor activities, this study establishes PHBV/PLGA as a novel promising drug delivery platform for treatment of colon cancer.

Improved oral delivery of tilianin through lipid-polymer hybrid nanoparticles to enhance bioavailability

Tilianin (TIL) may prevent and treat myocardial ischemia reperfusion injuries. However, its oral administration is hampered by its low bioavailability. The present study aimed to formulate lipid-polymer hybrid nanoparticles (LPHNs) as carriers for the sustained release and oral bioavailability enhancement of TIL in vitro and in vivo. A nanodrug delivery system of TIL-loaded LPHNs (TIL-LPHNs) was constructed. TIL-LPHNs were prepared via a self-assembly method, and their particle size, polymer dispersity index (PDI), zeta potential, encapsulation efficiency (EE) and morphology were investigated. In addition, pharmacokinetic studies were performed in vivo. The TIL-LPHN formulation produced a spherical, homogeneous, smooth surface and multi-lamellar structured nanoparticles. The particle size and distribution profile of TIL-LPHNs had a mean particle diameter of 54.6 ± 5.3 nm and PDI of 0.112 ± 0.017. The zeta potential was -33.4 ± 4.7 mV. The EE of TIL-LPHNs was 86.6 ± 3.6%, which was determined with the dialysis method. The TIL-LPHNs significantly enhanced the oral bioavailability of TIL with a 3.7-fold increase in the area under the concentration-time curve in comparison with the TIL solution. These findings support the potential use of LPHNs in improving the stability and bioavailability of TIL via oral administration.

Development of Triptolide Self-Microemulsifying Drug Delivery System and Its Anti-tumor Effect on Gastric Cancer Xenografts

Purpose: To develop a triptolide (TP) self-microemulsifying drug delivery system and to investigate its anti-tumor effect on human gastric cancer line MGC80-3 xenografts in nude mice.

Methods: The medium chain triglyceride (MCT) was selected as oil phase; polyoxyethylene castor oil (EL) was selected as surfactant, and PEG-400 was selected as cosurfactant. The mass ratio of each phase was optimized by central composite design and response surface methodology to prepare TP-SMEDDS (self-microemulsifying drug delivery system). The quality of TP-SMEDDS was evaluated, and its inhibitory effect on tumor growth investigated in nude mice transplanted with MGC80-3 cells.

Results: The final prescription process was defined as follows: MCT mass ratio: 25.3%; EL mass ratio: 49.6%; PEG-400 mass ratio: 25.1%. The prepared TP-SMEDDS was a transparent liquid with a clear appearance (the theoretical particle size: 31.168 nm). On transmission electron microscopy, the microemulsion particles were spherical in size and uniformly distributed without adhesions. The in vitro release experiment showed complete release of the prepared TP-SMEDDS in PBS solution in 6 h. In vivo antitumor activity showed its inhibitory effect in the xenograft model.

Conclusion: The self-microemulsifying delivery system improved the oral bioavailability and the in vivo antitumor effect of TP.

New folate receptor targeted nano liposomes for delivery of 5-fluorouracil to cancer cells: Strong implication for enhanced potency and safety

We previously showed that folate liposomes of 5FU made from Dipalmitoylphosphatidylcholine (DPPC) induced cell death in HT-29 and HeLa cells more potently than bulk 5FU. Also, a primary 5FU liposomal formulation with phosphatidyl choline (PC) exhibited higher cytotoxicity in murine colon cancer cells. In the present study, optimization of 5FU PC liposome, mechanism of cell death induction in human cancer cell lines and its safety along with other assays have been employed for targeted PC liposomes of 5FU. Liposomes were prepared using thin layer method and optimization of preparation was assessed using central composite design (CCD) of response surface methodology (RSM). Folic acid (FA) was employed as the targeting ligand. Morphology of 5FU loaded liposomes and changes in their thermal behavior were assessed by transmission electron microscopy (TEM) and differential scanning calorimetry (DSC), respectively. In vitro cytotoxicity was explored using MTT assay in HT-29, Caco-2, HeLa and MCF-7 cell lines. Cytotoxicity mechanism of the targeted delivery system was searched through the evaluation of reactive oxygen species (ROS) overproduction, mitochondrial membrane potential (∆Ψ_m), the release of cytochrome c, the activity of caspase 3/7 and apoptosis and necrosis rate. Liposomes were spherical in shape and 5FU was successfully encapsulated into liposomes rather in an amorphous state. Our interesting results showed that in HT-29 cells targeted liposomes triggered the mitochondrial apoptotic pathway by decreasing the mitochondrial membrane potential, releasing of cytochrome c and promoting the substantial activity of caspase 3/7. In HeLa cells, however, targeted liposomes particularly activated necrosis pathway through the overproduction of ROS. Folate-liposomal 5FU showed significantly higher antitumor efficiency compared to free drug. The results of this study offer new prospects for cancer therapy with reducing systemic drug exposure and associated toxicities.

Recent Advances in Drug Delivery System for Bioactive Glycosides from Traditional Chinese Medicine

Traditional Chinese Medicine (TCM) has been used in China for thousands of years for the prevention and treatment of various diseases. The materials that exert a therapeutic effect are called the active ingredients. The bioactive glycosides are important active ingredients from TCM that can make significant contributions to treating diseases. Because of the possibilities of various clinical applications, the properties and administration of these bioactive glycosides deserve further investigation. Their promising treatment effects, however, are hindered by their poor solubility, poor stability and rapid elimination. Therefore, it is necessary that we improve the therapeutic efficacy of bioactive glycosides by overcoming these problems. Meanwhile, some practical design strategies and novel drug delivery vehicles based on drug delivery systems provide favorable support in clinical practice for these active ingredients. This review summarizes diverse pharmacological activities of bioactive glycosides and focuses on recent advances in delivery system for these active constitutes; in particular, some glycol glycosides can effectively cure intractable diseases through targeted drug delivery. This review elucidates some design strategies for drug delivery system that are mainly based on two methods (avoiding physical barriers by changing dosage forms and enhancing the ability to bind to receptors or proteins after administration) and indicate the current challenges during the combination of delivery vehicles and these glycosides in hopes of promoting the process of receiving ideal therapeutic efficacy of them in future studies.

Liposome-Encapsulated Baicalein Suppressed Lipogenesis and Extracellular Matrix Formation in Hs68 Human Dermal Fibroblasts

The dermis of human skin contains large numbers of fibroblasts that are responsible for the production of the extracellular matrix (ECM) that supporting skin integrity, elasticity and wound healing. Previously, an in vivo study demonstrated that dermal fibroblasts siting in the lower dermis are capable to convert into skin adipose layer and hence fibroblast lipogenesis may vary the structure and elasticity of dermis. In the present study, Hs68 human dermal fibroblasts were utilized as an in vitro model to study the lipogenesis via using adipogenic differentiation medium (ADM). Baicalein, isolated from Scutellaria baicalensis, is one of the flavonoids to inhibit adipocyte differentiation due to high antioxidant activity in vitro. In order to develop a suitable formulation for baicalein (a poorly water-soluble drug), soybean phosphatidylcholine (SPC) was used to prepare baicalein-loaded liposomes to enhance drug bioavailability. Our results demonstrated that liposome-encapsulated baicalein protected cell viability and increased cellular uptake efficiency of Hs68 fibroblasts. Lipid accumulation, triglyceride synthesis and gene expressions of lipogenesis enzymes (FABP4 and LPL) were significantly increased in ADM-stimulated Hs68 fibroblasts but subsequently suppressed by liposome-encapsulated baicalein. In addition, ADM-induced TNF-α expression and related inflammatory factors was down-regulated by liposome-encapsulated baicalein. Through ADM-induced lipogenesis, the protein expression of elastin, type I and type III collagens increased remarkably, whereas liposome-encapsulated baicalein can down-regulate ADM-induced ECM protein synthesis. Taken together, we found that liposome-encapsulated baicalein can inhibit ADM-induced lipid accumulation and ECM formation in Hs68 fibroblasts through the suppression of lipogenesis enzymes and inflammatory responses. Liposome-encapsulated baicalein may have the potential to improve wound healing and restore skin structure after skin injury.

Cardioprotection of tilianin ameliorates myocardial ischemia-reperfusion injury: Role of the apoptotic signaling pathway

Our previous research demonstrated that tilianin protects the myocardium in a myocardial ischemia reperfusion injury (MIRI) rat model and has prominent pharmacological potential as a cardiovascular drug. Our study aimed to investigate the molecular signaling implicated in the improvement of myocardial survival induced by tilianin, a flavonoid antioxidant. Tilianin (2.5, 5, and 10 mg/kg/d) or saline was orally administered to rats for 14 days. On the 15th day, ischemia was induced by ligating the left anterior descending artery for 45 min, followed by 4 h of reperfusion. The levels of MIRI-induced serum myocardial enzymes and cardiomyocyte apoptosis as well as infarct size were examined to assess the cardioprotective effects. Cardiac tissues were collected for western blot analyses to determine the protein expression of anti-apoptotic signaling molecules. In MIRI-treated rats, our results revealed that pre-administration of high dose-tilianin the reduced release of LDH, MDA, and CK-MB and increased the plasma SOD level, and significantly attenuated the infarct size. Western blot analysis showed that a remarkable rise in expression of Bcl-2 and XIAP, and decline in expression of Bax, Smac/Diablo, HtrA2/Omi, cleaved caspase-3, caspase-7 and caspase-9 was observed in the myocardium. The apoptosis index of cardiomyocytes further supports the cardioprotective effect of tilianin. Additionally, compared with the MIRI model group, pretreatment with high dose-tilianin group upregulated phosphorylated Akt and PI3K. In contrast, using the PI3K inhibitor LY294002 to block Akt activation effectively inhibited the protective effects of tilianin against MIRI. Tilianin pretreatment was beneficial for activating the PI3K/Akt signaling pathway and inhibiting myocardial apoptosis.

Optimization of the Preparation Conditions of Borneol-Modified Ginkgolide Liposomes by Response Surface Methodology and Study of Their Blood Brain Barrier Permeability

Ginkgolides (GG), containing ginkgolide A (GA), ginkgolide B (GB) and ginkgolide C (GC), are mainly prescribed for ischemic stroke and cerebral infarction. However, the ginkgolides can hardly pass the blood-brain barrier (BBB) into the brain. The purpose of this study was to prepare borneol-modified ginkgolides liposomes (GGB-LPs) to study whether borneol could enhance the transport of ginkgolides across the BBB. The preparation conditions of GGB-LPs were optimized by a response surface-central composite design. Also, pharmacokinetics and biodistribution studies of GGB-LPs were conducted using UPLC-MS. The optimal preparation conditions for GGB-LP were as follows: ratio of lipid to drug (w/w) was 9:1, ratio of phospholipid to cholesterol (w/w) was 7:1, and hydrate volume was 17.5 mL. Under these conditions, the GGB-LP yield was 89.73 ± 3.45%. With GGB-LPs, borneol significantly promoted the transport of ginkgolide across the BBB. The pharmacokinetic parameters of GGB-LP were significantly improved too, with T_max of 15 min and a high drug concentration of 3.39 μg/g in brain. Additionally, the drug targeting index and relative uptake rate of GGB-LP was increased. Borneol-modified ginkgolide liposomes can thus potentially be used to improve the BBB permeability of gingkolide formulations.

Optimization of Conditions for Cyanidin-3-OGlucoside (C3G) Nanoliposome Production by Response Surface Methodology and Cellular Uptake Studies in Caco-2 Cells

We aimed to optimize the formulation of C3G nanoliposomes using response surface methodology. Additionally, we evaluated the stability, particle change, and encapsulation efficiency (EE) of C3G nanoliposomes under different temperatures and storage durations, as well as in simulated gastrointestinal juice (SGF) and simulated intestinal fluid. The morphology of C3G nanoliposomes was observed by transmission electron microscope. The ability of C3G nanoliposomes to affect cancer cell morphology and inhibit cancer cell proliferation was studied with Caco-2 cells. Reverse-phase evaporation method is a simple and efficient method for liposome preparation. The optimal preparation conditions for this method were as follows: C3G concentration of 0.17 mg/mL, phosphatidylcholine/cholesterol ratio of 2.87, and rotary evaporation temperature of 41.41 °C. At optimal conditions, the particle size and EE of the C3G nanoliposomes were 165.78 ± 4.3 nm and 70.43% ± 1.95%, respectively. The C3G nanoliposomes showed an acceptable stability in SGF at 37 °C for 4 h, but were unstable under extended storage durations and high temperatures. Moreover, our results showed that different concentrations of C3G nanoliposomes affected the morphology and inhibited the proliferation of Caco-2 cells.

Liposome encapsulation attenuated venenum bufonis induced vascular irritation in rabbit ear vein via regulating TLR/MAPK/NF-κB pathway

Venenum bufonis (VB) induced vascular irritation was related with the regulation of TLR/MAPK/NF-κB signaling pathway, and liposome encapsulation significantly attenuated VB induced vascular irritation while maintaining its anticancer activity.

Tissue distribution and enhanced in vivo anti-hyperlipidemic-antioxidant effects of perillaldehyde-loaded liposomal nanoformulation against Poloxamer 407-induced hyperlipidemia

An optimized perillaldehyde-loaded liposomal nanoformulation (PAH-LNF) was successfully applied to improve the pharmacological effect of perillaldehyde (PAH) in poloxamer 407-induced hyperlipidemia. Oral administration of PAH-LNF (240mg/kg per body weight) in rats significantly enhanced solubility and relative bioavailability (270.7%) compared to the free PAH with about 2.7-, 1.5-, 1.3-, 1.3- and 1.5-fold increase in AUC, T_1/2, MRT, C_max and T_max, respectively. Tissue distribution study also revealed the accumulation of PAH in the liver, lungs, spleen, kidney, brain and heart in order of decreasing affinity. Moreover, a significant decrease in serum total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) with simultaneous increase in high-density lipoprotein cholesterol (HDL-C) level was observed in the chemically-induced hyperlipidemic mice which further confirmed PAH's anti-hyperlipidemic properties. Additionally, PAH-LNF also significantly increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) with a concurrent decrease in malondialdehyde (MDA) to affirm the antioxidant and hepatoprotective effects of PAH. Thus, liposomal nanoformulation promises to be a useful drug delivery system for the development of PAH.

Highly selective and efficient biotransformation of linarin to produce tilianin by naringinase

OBJECTIVES

To develop a practical method to prepare tilianin by highly selective and efficient hydrolysis of the C-7 rhamnosyl group from linarin.

RESULTS

Naringinase was utilized to selectively catalyze the formation of tilianin using linarin as the starting material. The reaction conditions, including temperature, pH, metal ions, substrate concentration and enzyme concentration, were optimized. At 60 °C, naringinase showed enhanced α-L-rhamnosidase activity while the β-D-glucosidase activity was abrogated. The addition of Mg(2+), Fe(2+) and Co(2+) was also beneficial for selective biotransformation of linarin to tilianin. Under the optimized conditions (pH 7.0 at 60 °C), linarin could be nearly completely transformed to tilianin with excellent selectivity (>98.9 %), while that of the by-product acacetin was less than 1.1 %. In addition, the structure of target product tilianin was fully characterized by HR-MS and (1)H-NMR.

CONCLUSION

A highly selective and efficient biotransformation of linarin to tilianin was developed by the proper control of incubation temperature, which enhanced the α-L-rhamnosidase activity of naringinase and blocked its β-D-glucosidase activity.