A novel submicron emulsion system loaded with vincristine-oleic acid ion-pair complex with improved anticancer effect: in vitro and in vivo studies

Chemosensitizer Loaded NIR-Responsive Nanostructured Lipid Carriers: A Tool for Drug-Resistant Breast Cancer Synergistic Therapy

Although numerous technical advances have been made in cancer treatment, chemotherapy is still a viable treatment option. However, it is more effective when used in combination with photothermal therapy for resistant breast cancer cells. This study introduces a smart drug delivery system, (DOX-OA+VERA+AuNRs)@NLC, which is designed for dual chemo/photothermal therapy of multiple-drug-resistant breast cancer. Type-III nanostructured lipid carriers (NLCs) were used as drug delivery systems, where nano-in-nano structures offer several advantages. Doxorubicin (DOX) was used as the antitumor agent by ion-pairing it with oleic acid (OA) to increase the DOX loading capacity, as well as to reduce the burst release of the drug. Verapamil (VERA), which was used as a chemosensitizer to overcome the multiple-drug resistance, was co-loaded with DOX-OA. Gold nanorods (AuNRs) were exploited as the photothermal therapy agent in photothermal therapy (PTT) application, which would have a synergistic relation with chemotherapy. The release of DOX-OA and VERA from NLCs was studied in vitro by triggering with NIR laser irradiation. Thus, an all-in-one drug delivery system was designed to release the active pharmaceutical ingredients (APIs) at higher concentrations in the desired region and provide both chemo/PTT. Besides, the application of a folic acid-chitosan (FA-CS) coating to NLCs has facilitated the development of systems capable of targeting and specifically releasing their cargo within cancerous tissues while preserving their surrounding environment.

Herbal Theranostics: Controlled, Targeted Delivery and Imaging of Herbal Molecules

Modern medicine relies on a small number of key biologics, which can be found in nature but require further characterization and purification before they can be used. Since the herbal remedy is given through a dated and ineffective method of drug administration, its effectiveness is diminished. The novel form of medicine delivery has the potential to increase the effectiveness of herbal substances while decreasing their side effects. This is the main idea behind utilising different ways of drug delivery in herbal treatments. Several benefits arise from novel formulations of herbal compounds as compared to their conventional counterparts. These include enhanced penetrating ability into tissues, constant delivery of effective doses, and resistance to physical and chemical degradation. Controlled and targeted delivery that include herbal components allow for more traditional dosing while simultaneously increasing their efficacy. Enhancing the biodistribution and target site accumulation of systemically administered herbal medicines is the goal of nanomedicine formulations. The field of nanotheranostics has made significant advancements in the development of herbal compounds by combining diagnostic and therapeutic functions on a single nanoscale platform. It is critically important to create a theranostic nanoplatform that is derived from plants and is intrinsically "all-in-one" for single molecules. In addition to examining the mechanistic approach to nanoparticle synthesis, this review highlights the therapeutic effects of nanoscale phytochemical delivery systems. Furthermore, we have evaluated the scope for future advancements in this field, discussed several nanoparticles that have been developed recently for herbal imaging, and provided experimental evidence that supports their usage.

Alendronate-Grafted Nanoemulsions for Bone-Targeted Vincristine Delivery: Preliminary Studies on Cell and Animal Models

Bone is a site of distant metastases, which are a common cause of morbidity and mortality with a high socio-economic impact, for many malignant tumours. In order to engineer pharmacological therapies that are suitable for this debilitating disease, this experimental work presents injectable lipid nanoemulsions, which are endowed with a long history of safe clinical usage in parenteral nutrition, their loading with vincristine and their grafting with alendronate, with a dual purpose: merging the anticancer activity of bisphosphonates and vincristine, and enhancing bone-targeted delivery. In cell studies, alendronate synergised with the anti-migration activity of vincristine, which is important as migration plays a key role in the metastatisation process. In preliminary animal studies, carried out thanks to IVIS technology, alendronate conjugation enhanced the bone targeting of fluorescently labelled nanoemulsions. These encouraging results will drive further studies on suitable animal models of the disease.

Acacia Honey-derived Bioactive Compounds Exhibit Induction of p53-dependent Apoptosis in the MCF-7 Human Breast Cancer Cell Line

Background

Research studies have focused on discovering new anti-proliferative and pro-apoptotic agents derived from natural products from which honey constitutes a prominent candidate. The Acacia honey (AH) is known to display anticancer activity, but the mechanisms of action are still not well defined.

Objectives

Using in vitro and computational approaches, we aimed to assess the interaction among selected bioactive compounds derived from AH, with the apoptotic protein p53, which could trigger apoptosis.

Methods

The phytocompounds of AH were investigated via gas chromatography–mass spectrophotometry analysis. The cytotoxic effect and induced apoptosis on the MCF-7 breast cancer cell line were assessed by 3-(4,5-dimethylthiazolyl-2)-2,5 diphenyltetrazolium bromide and acridine orange-ethidium bromide staining approaches. The molecular docking analysis between AH compounds and p53 was carried out.

Results

The drug-likeness prediction revealed that most of the identified compounds meet Lipinski’s rules. We demonstrate that AH exerts an interesting cytotoxic effect in a dose-dependent manner against the MCF-7 cell line with IC50 5.053µg/mL. Significant cell alterations and notable induced apoptosis were detected when cells were treated with AH. The molecular docking analysis revealed that melezitose is among the most important potential bioactive compounds that interact with p53 leading to apoptosis. The binding affinity was −8.1 kcal/mol, and the closest molecular interactions in the active site included 10 residues, which could explain the potential biological activity.

Conclusion

This work sheds light on AH as a significant source of bioactive chemicals with potential for promoting apoptosis that may be exploited as an alternative therapy for breast cancer.

Antitumor Effects of a Solid Lipid Nanoparticle Loaded with Gemcitabine and Oxaliplatin on the Viability, Apoptosis, Autophagy and Hsp90 of Ovarian Cancer Cells

Aim: The present study aimed to explore the sensitizing capability of the anticancer agents, gemcitabine (GEM) and oxaliplatin (OXA), encapsulated in a novel SLN (GEM:OXA-SLN) against the ovarian cancer cell lines.

METHODS

A novel SLN, prepared using hot homogenization by mixing phosphatidylcholine, cholesterol, tween 80 and oleic acid, was characterized using Transmission Electron Microscope and zetasizer. The anticancer activities and the underlying molecular mechanisms of GEM:OXA-SLN were investigated.

RESULTS

The average z-diameter of the homogeneous spherical GEM:OXA-SLN was (70.33 ± 0.70) nm with zeta potential (-7.69 ± 0.61) mV. GEM:OXA-SLN significantly inhibited the viability of ovarian cancer cells in a dose-dependent manner within 24 h. It also triggered the induction of autophagy cellular death, suppression of multidrug resistance efflux pump and inhibition of heat shock protein (Hsp90).

CONCLUSION

The encapsulation of GEM and OXA in SLN improved the efficacy of the drugs and diminished the ovarian cancer cell's resistance.

Targeted therapy of rheumatoid arthritis via macrophage repolarization

The polarization of macrophages plays a critical role in the physiological and pathological progression of rheumatoid arthritis (RA). Activated M1 macrophages overexpress folate receptors in arthritic joints. Hence, we developed folic acid (FA)-modified liposomes (FA-Lips) to encapsulate triptolide (TP) (FA-Lips/TP) for the targeted therapy of RA. FA-Lips exhibited significantly higher internalization efficiency in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells than liposomes (Lips) in the absence of folate. Next, an adjuvant-induced arthritis (AIA) rat model was established to explore the biodistribution profiles of FA-Lips which showed markedly selective accumulation in inflammatory paws. Moreover, FA-Lips/TP exhibited greatly improved therapeutic efficacy and low toxicity in AIA rats by targeting M1 macrophages and repolarizing macrophages from M1 to M2 subtypes. Overall, a safe FA-modified liposomal delivery system encapsulating TP was shown to achieve inflammation-targeted therapy against RA via macrophage repolarization.

Anticancer potential of indole derivatives: an update

The heterocyclic indole is one of the most prevalent pharmacophores in nature. It has been a highly privileged scaffold for designing targeted and anticancer therapeutics. Countless fused heterocyclic templates have been developed with diverse physicochemical and biological properties. Due to their versatile ethanobotanical and pharmacological values, indole and its derivatives seek high demand in the chemical and healthcare sectors. Extensive anticancer research has been conducted in this decade to evaluate their efficacy for diverse malignancies. The chapter explores the anticancer activity of natural and synthetic indole derivatives expressed through targeting different biological receptors and enzymes.

Curcumin- and Cyclopamine-Loaded Liposomes to Enhance Therapeutic Efficacy Against Hepatic Fibrosis

BACKGROUND AND PURPOSE

Hepatic fibrosis is a public health problem characterized by activation of hepatic stellate cells (HSCs), which triggers excessive production of extracellular matrix (ECM). Inhibition of HSC activation may be an effective treatment. Since various pathways control HSC activation, a combination of drugs with different mechanisms may be more effective than monotherapy.

METHODS

Here, we prepared liposomes loaded with curcumin and cyclopamine to inhibit HSC activation. We systematically analyzed the physicochemical characteristics of liposomes loaded with the two drugs, as well as their effects on HSC proliferation, activation and collagen production on gene, protein and cellular levels.

RESULTS

The prepared liposomes helped solubilize both drugs, contributing to their uptake by cells. Liposomes loaded with both drugs inhibited cell proliferation, migration and invasion, as well as induced more apoptosis and perturbed the cell cycle more than the free combination of both drugs in solution or liposomes loaded with either drug alone. Liposomes loaded with both drugs strongly suppressed HSC activation and collagen secretion.

CONCLUSION

Our results suggest that liposome encapsulation can increase the uptake of curcumin and cyclopamine as well as the synergism between them in anti-fibrosis. This approach shows potential for treating hepatic fibrosis.

Co-delivery of doxorubicin, docosahexaenoic acid, and α-tocopherol succinate by nanostructured lipid carriers has a synergistic effect to enhance antitumor activity and reduce toxicity

Doxorubicin (DOX) is widely used in cancer treatment, however, its use is often limited due to its side effects. To avoid these shortcomings, the encapsulation of DOX into nanocarriers has been suggested. Herein, we proposed a novel nanostructured lipid carrier (NLC) formulation loading DOX, docosahexaenoic acid (DHA), and α-tocopherol succinate (TS) for cancer treatment. DHA is an omega-3 fatty acid and TS is a vitamin E derivative. It has been proposed that these compounds can enhance the antitumor activity of chemotherapeutics. Thus, we hypothesized that the combination of DOX, DHA, and TS in NLC (NLC-DHA-DOX-TS) could increase antitumor efficacy and also reduce toxicity. NLC-DHA-DOX-TS was prepared using emulsification-ultrasound. DOX was incorporated after preparing the NLC, which prevented its degradation during manufacture. High DOX encapsulation efficiency was obtained due to the ion-pairing with TS. This ion-pairing increases lipophilicity of DOX and reduces its crystallinity, contributing to its encapsulation in the lipid matrix. Controlled DOX release from the NLC was observed in vitro, with increased drug release at the acidic environment. In vitro cell studies indicated that DOX, DHA, and TS have synergistic effects against 4T1 tumor cells. The in vivo study showed that NLC-DHA-DOX-TS exhibited the greatest antitumor efficacy by reducing tumor growth in 4T1 tumor-bearing mice. In addition, this formulation reduced mice mortality, prevented lung metastasis, and decreased DOX-induced toxicity to the heart and liver, which was demonstrated by hematologic, biochemical, and histologic analyses. These results indicate that NLC-DHA-DOX-TS may be a promising carrier for breast cancer treatment.

Liquiritigenin-Loaded Submicron Emulsion Protects Against Doxorubicin-Induced Cardiotoxicity via Antioxidant, Anti-Inflammatory, and Anti-Apoptotic Activity

Background

The clinical use of doxorubicin (DOX) is severely limited due to its cardiotoxicity. Thus, there is a need for prophylactic and treatment strategies against DOX-induced cardiotoxicity.

Purpose

The purpose of this study was to develop a liquiritigenin-loaded submicron emulsion (Lq-SE) with enhanced oral bioavailability and to explore its efficacy against DOX-induced cardiotoxicity.

Methods

Lq-SE was prepared using high-pressure homogenization and characterized using several analytical techniques. The formulation was optimized by central composite design response surface methodology (CCD-RSM). In vivo pharmacokinetic studies, biochemical analyses, reactive oxygen species (ROS) assays, histopathologic assays, and Western blot analyses were performed.

Results

Each Lq-SE droplet had a mean particle size of 221.7 ± 5.80 nm, a polydispersity index (PDI) of 0.106 ± 0.068 and a zeta potential of -28.23 ± 0.42 mV. The area under the curve (AUC) of Lq-SE was 595% higher than that of liquiritigenin (Lq). Lq-SE decreased the release of serum cardiac enzymes and ameliorated histopathological changes in the hearts of DOX-challenged mice. Lq-SE significantly reduced oxidative stress by adjusting the levels of ROS, increasing the activity of antioxidative enzymes and inhibiting the protein expression of NOX4 and NOX2. Furthermore, Lq-SE significantly improved the inflammatory response through the mitogen-activated protein kinase (MAPK)/nuclear factor-κB (NF-κB) signalling pathway and induced cardiomyocyte apoptosis.

Conclusion

Lq-SE could be used as an effective cardioprotective agent against DOX in chemotherapy to enable better treatment outcomes.

Aprepitant Intravenous Emulsion Based on Ion Pairing/Phospholipid Complex for Improving Physical and Chemical Stability During Thermal Sterilization

An aprepitant (APT) cholesteryl hemisuccinate (CHEMS) ion pair complex emulsion (AIPE) with high lecithin content was prepared to improve sterilization stability through the film dispersion homogenization method; therefore, it could be a promising delivery system of APT. Medium-chain triglycerides (MCT) was selected as the oil phase to improve the solubility and stability of APT in oil phase. DSC, XRD, FT-IR, and ¹H-NMR spectroscopies confirmed that the APT-CHEMS ion pair (AIP) was formed between CHEMS and APT. The formation of AIP significantly increased the hydrophobicity of APT, allowing it to be completely embedded in the oil phase core to improve chemical stability and decrease hydrolysis of APT in the water phase. Also, CHEMS had a strong affinity with lecithin and could stabilize lipid membranes, forming a stronger and thicker interface membrane to increase the physical stability of AIPE. As a result, AIPE could withstand autoclaving at 120°C for 8 min without any change of particle size or content. Furthermore, AIPE with a potential of - 53.4 mV remained stable through spatial repulsion during sterilization. The encapsulation efficiency of AIPE was over 90% and the particle size was 106.8 ± 65.62 nm(0.286). Pharmacokinetic study in rats was comparable with that of CINVANTI which yielded a relative bioavailability of 114.31% indicating that the AIPE had similar pharmacokinetic processes in vivo with the analog of CINVANTI®. The AUC0-t of the AIPE was 4.31-fold that of the APT solution.

Hydrophobic ion pairing: encapsulating small molecules, peptides, and proteins into nanocarriers

Hydrophobic ion pairing has emerged as a method to modulate the solubility of charged hydrophilic molecules ranging in class from small molecules to large enzymes. Charged hydrophilic molecules are ionically paired with oppositely-charged molecules that include hydrophobic moieties; the resulting uncharged complex is water-insoluble and will precipitate in aqueous media. Here we review one of the most prominent applications of hydrophobic ion pairing: efficient encapsulation of charged hydrophilic molecules into nano-scale delivery vehicles - nanoparticles or nanocarriers. Hydrophobic complexes are formed and then encapsulated using techniques developed for poorly-water-soluble therapeutics. With this approach, researchers have reported encapsulation efficiencies up to 100% and drug loadings up to 30%. This review covers the fundamentals of hydrophobic ion pairing, including nomenclature, drug eligibility for the technique, commonly-used counterions, and drug release of encapsulated ion paired complexes. We then focus on nanoformulation techniques used in concert with hydrophobic ion pairing and note strengths and weaknesses specific to each. The penultimate section bridges hydrophobic ion pairing with the related fields of polyelectrolyte coacervation and polyelectrolyte-surfactant complexation. We then discuss the state of the art and anticipated future challenges. The review ends with comprehensive tables of reported hydrophobic ion pairing and encapsulation from the literature.

Design and evaluation of glomerulus mesangium-targeted PEG-PLGA nanoparticles loaded with dexamethasone acetate

Mesangial proliferative glomerulonephritis (MsPGN), one of the most common glomerulonephritis pathological types, often leads to end-stage renal disease over a prolonged period. But the current treatment of MsPGN is non-specific and causes serious side effects, thus novel therapeutics and targeting strategies are urgently demanded. By combining the advantages of PEG-PLGA nanoparticles and the size selection mechanism of renal glomerulus, we designed and developed a novel PEG-PLGA nanoparticle delivery system capable of delivering dexamethasone acetate (A-DEX) into glomerular mesangium. We determined that 90 nm was the optimum size to encapsulate A-DEX for glomerular mesangium targeting based on the size-selection mechanism of glomerulus. After intravenous administration in rats, 90 nm DiD-loaded NPs were found to accumulate to a greater extent in the kidney and kidney cortex compared with the free DiD solution. The 90 nm A-DEX NPs are also more stable at room temperature and showed a sustained release pattern. In rat glomerular mesangial cells (HBZY-1) in vitro, we found that the uptake of 90 nm A-DEX NPs was both temperature-dependent and energe-dependent, and they were mostly engulfed via clathrin-dependent endocytosis pathways. In summary, we have successfully developed a glomerular mesangium-targeted PEG-PLGA NPs, which is potential for the treatment of MsPGN.

Developments in drug delivery of bioactive alkaloids derived from traditional Chinese medicine

The bioactive alkaloids (e.g. vincristine, hydroxycamptothecin, ligustrazine, and so on) from traditional Chinese medicine (TCM) have exerted potent efficacies (e.g. anti-tumor, anti-inflammation, immunosuppression, etc.). However, a series of undesirable physicochemical properties (like low solubility and weak stability) and baneful pharmacokinetic (PK) profiles (e.g. low bioavailability, short half time, rapid clearance, etc.) have severely restricted their applications in clinic. In addition, some side effects (like cumulative toxicities caused by high-frequency administration and their own toxicities) have recently been reported and also confined their clinical uses. Therefore, developments in drug delivery of such alkaloids are of significance in improving their drug-like properties and, thus, treatment efficiencies in clinic. Strategies, including (i) specific delivery via liposomes; (ii) sustained delivery via nanoparticles, gels, and emulsions; and (iii) transdermal delivery via ethosomes, solid lipid nanoparticles, and penetrating enhancers, have been reported to improve the pharmacokinetic and physicochemical characters of problematic TCM alkaloids, decline their adverse effects, and thus, boost their curative efficacies. In this review, the recent reports in this field were comprehensively summarized with the aim of providing an informative reference for relevant readers.

Targeted delivery of celastrol to mesangial cells is effective against mesangioproliferative glomerulonephritis

Mesangial cells-mediated glomerulonephritis is a frequent cause of end-stage renal disease. Here, we show that celastrol is effective in treating both reversible and irreversible mesangioproliferative glomerulonephritis in rat models, but find that its off-target distributions cause severe systemic toxicity. We thus target celastrol to mesangial cells using albumin nanoparticles. Celastrol-albumin nanoparticles crosses fenestrated endothelium and accumulates in mesangial cells, alleviating proteinuria, inflammation, glomerular hypercellularity, and excessive extracellular matrix deposition in rat anti-Thy1.1 nephritis models. Celastrol-albumin nanoparticles presents lower drug accumulation than free celastrol in off-target organs and tissues, thereby minimizing celastrol-related systemic toxicity. Celastrol-albumin nanoparticles thus represents a promising treatment option for mesangioproliferative glomerulonephritis and similar glomerular diseases.

Mesangial cell-mediated glomerulonephritis is a frequent cause of kidney disease. Here the authors show that celastrol loaded in albumin nanoparticles efficiently targets mesangial cells, and is effective in rat models.

Vincristine-loaded liposomes prepared by ion-paring techniques: Effect of lipid, pH and antioxidant on chemical stability

In the present study, vincristine (VCR)-loaded liposomes were designed by ion-pairing techniques and the model could be applied to investigate the effect of lipids on the degradation of vinca alkaloids, and how to weaken their influence by adjusting pH and adding antioxidants. It was found that there was a positive correlation between degree of degradation and the unsaturation extent of the phospholipids. In the phospholipid with the lowest oxidation index, only 6% of VCR was degraded in 6days at 37°C, whereas for the phospholipids with highest oxidation index, the degradation reached above 95% over the same time. At pH6.8 and 7.4, the degradation rate of VCR in the lipid membrane was significantly faster than that in aqueous solution, instead, at pH5.0. After the addition of butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), tocopherol, ascorbate and tocopherol with ascorbate, the residual content of VCR after 6days was 79.9%, 78.1%, 7.1%, 89.6% and 94.6% respectively. It was speculated that VCR could be oxidized by hydrated peroxyl radicals, which formed from lipid peroxidation as well as nucleophilic substitution with peroxyl radicals in the dry state. Also, the antioxidants were shown to have different eliminating capacity on the peroxyl radicals whether hydrated or not, and the phenoxyl radicals generated from fat-soluble antioxidants may be potentially destabilizing to VCR. Therefore, for these two crucial reasons, the degradation of VCR was quite different when used with a combination of water and fat-soluble antioxidants, and thus provides the best protection for VCR.

Membrane-Loaded Doxorubicin Liposomes Based on Ion-Pairing Technology with High Drug Loading and pH-Responsive Property

In order to achieve high drug loading and high entrapment efficiency, a doxorubicin-cholesteryl hemisuccinate ion-pair complex (DCHIP) was formed, and the ion-pair complex liposomes (DCHIP-Lip) were prepared based on conventional thin-film dispersion method. Firstly, DCHIP was fabricated and confirmed with FTIR, ¹H-NMR, DSC, and XRD techniques. Afterwards, DCHIP-Lip were prepared and evaluated in terms of particle size, zeta potential, entrapment efficiency, and drug loading content. Finally, the in vitro and in vivo behavior of liposomes was further investigated. The DCHIP-Lip had a nanoscale particle size of about 120 nm with a negative zeta potential of about -22 mV. In addition, the entrapment efficiency and drug loading content of DOX reached 6.4 ± 0.05 and 99.29 ± 0.3%, respectively. Importantly, the release of DCHIP-Lip was pH sensitive and increased cell toxicity against MCF-7 cells was achieved. Upon dilution, the liposomes were fairly stable under physiological conditions. The in vivo pharmacokinetic study indicated that the AUC of DOX in DCHIP-Lip was 11.48-fold higher than that of DOX-HCl solution and the in vivo antitumor activity of DCHIP-Lip showed less body weight loss and a significant prohibition effect of tumor growth. Based on these findings, it can be seen that the ion-pairing technology combined with conventional liposome drug loading method could be used to achieve high drug loading and it could be valuable for the study of liposomal delivery system.

Lipophilic salts of poorly soluble compounds to enable high-dose lipidic SEDDS formulations in drug discovery

Self-emulsifying drug delivery systems (SEDDS) have been used to solubilize poorly water-soluble drugs to improve exposure in high-dose pharmacokinetic (PK) and toxicokinetic (TK) studies. However, the absorbable dose is often limited by drug solubility in the lipidic SEDDS vehicle. This study focuses on increasing solubility and drug loading of ionizable drugs in SEDDS vehicles using lipophilic counterions to prepare lipophilic salts of drugs. SEDDS formulations of two lipophilic salts-atazanavir-2-naphthalene sulfonic acid (ATV-2-NSA) and atazanavir-dioctyl sulfosuccinic acid (ATV-Doc)-were characterized and their performance compared to atazanavir (ATV) free base formulated as an aqueous crystalline suspension, an organic solution, and a SEDDS suspension, using in vitro, in vivo, and in silico methods. ATV-2-NSA exhibited ∼6-fold increased solubility in a SEDDS vehicle, allowing emulsion dosing at 12mg/mL. In rat PK studies at 60mg/kg, the ATV-2-NSA SEDDS emulsion had comparable exposure to the free-base solution, but with less variability, and had better exposure at high dose than aqueous suspensions of ATV free base. Trends in dose-dependent exposure for various formulations were consistent with GastroPlus™ modeling. Results suggest use of lipophilic salts is a valuable approach for delivering poorly soluble compounds at high doses in Discovery.

Novel oral administrated paclitaxel micelles with enhanced bioavailability and antitumor efficacy for resistant breast cancer

Paclitaxel (PTX) is a widely used antineoplastic drug in clinic. Due to poor aqueous solubility, it is administrated by intravenous infusion of cremophor EL containing formulation with serious adverse effects. The low oral bioavailability is a great challenge for oral formulation development. In addition, P-gp mediated multidrug resistance limit its clinical use in various resistant cancers. In this study, a novel super-antiresistant PTX micelle formulation for oral administration was developed. A P-gp inhibitor, bromotetrandrine (W198) was co-encapsulated in the micelle. The micelles were composed of Solutol HS 15 and d-a-tocopheryl polyethylene glycol succinate to avoid Cremophor EL induced toxicity. The micelles were round with a mean particle size of ∼13nm and an encapsulation efficiency of ∼90%. A series of in vitro evaluations were performed in non-resistant MCF-7 cells and resistant MCF-7/Adr cells. The super-antiresistant PTX micelles showed higher cell uptake efficiency, significantly increased cytotoxicity and antimitotic effect in drug resistant MCF-7/Adr cells when compared with Taxol and other PTX micelle formulations. Compared with Taxol, the super-antiresistant PTX micelles significantly improved bioavailability after oral administration in rats, and inhibited tumor growth in multidrug resistance xenografted MCF-7/Adr nude mice. In summary, the noval super-antiresistant PTX micelles showed a great potential for oral delivery of PTX against resistant breast cancer.

Correlation of Emulsion Structure with Cellular Uptake Behavior of Encapsulated Bioactive Nutrients: Influence of Droplet Size and Interfacial Structure

In this study, an in vitro Caco-2 cell culture assay was employed to evaluate the correlation between emulsion structure and cellular uptake of encapsulated β-carotene. After 4 h of incubation, an emulsion stabilized with whey protein isolate showed the highest intracellular accumulation of β-carotene (1.06 μg), followed by that stabilized with sodium caseinate (0.60 μg) and Tween 80 (0.20 μg), which are 13-, 7.5-, and 2.5-fold higher than that of free β-carotene (0.08 μg), respectively. Emulsions with small droplet size (239 ± 5 nm) showed a higher cellular uptake of β-carotene (1.56 μg) than emulsiond with large droplet size (489 ± 9 nm) (0.93 μg) (p < 0.01). The results suggested that delivery in an emulsion significantly improved the cellular uptake of β-carotene and thus potentially its bioavailability; uptake was closely correlated with the interfacial composition and droplet size of emulsions. The findings support the potential for achieving optimal controlled and targeted delivery of bioactive nutrients by structuring emulsions.

A study on liposomal encapsulation of a lipophilic prodrug of LHRH

This study aimed at evaluating whether derivatization of luteinizing hormone-releasing hormone (LHRH) peptide with an amphiphilic lipoamino acid moiety could allow, along with other technological and/or pharmacokinetic advantages, to improve its encapsulation in liposomes, potentially driving its further body distribution and cellular uptake. Experimental data confirmed that a lipophilic derivative of LHRH was efficiently incorporated in various liposomal systems, differing in lipid composition and surface charge, and obtained using different methods of production. Incubation of liposomes, loaded with a fluorescent derivative of the LHRH prodrug, with NCTC keratinocytes or Caco-2 cell cultures showed that the carriers can be rapidly internalized. Conversely, the internalization of the free prodrug occurred only at very high concentrations.

Drug delivery systems and combination therapy by using vinca alkaloids

Developing new methods for chemotherapy drug delivery has become a topic of great concern. Vinca alkaloids are among the most widely used chemotherapy reagents for tumor therapy; however, their side effects are particularly problematic for many medical doctors. To reduce the toxicity and enhance the therapeutic efficiency of vinca alkaloids, many researchers have developed strategies such as using liposome-entrapped drugs, chemical- or peptide-modified drugs, polymeric packaging drugs, and chemotherapy drug combinations. This review mainly focuses on the development of a vinca alkaloid drug delivery system and the combination therapy. Five vinca alkaloids (eg, vincristine, vinblastine, vinorelbine, vindesine, and vinflunine) are reviewed.

Cinnamaldehyde in a Novel Intravenous Submicrometer Emulsion: Pharmacokinetics, Tissue Distribution, Antitumor Efficacy, and Toxicity

The purpose of our research is to find a new lipid emulsion to deliver a low water-soluble compound, cinnamaldehyde (CA). Its characteristics, pharmacokinetics, antitumor efficacy, and toxicity were evaluated. The mean particle size, zeta potential, and encapsulation efficiency of the submicromemter emulsion of CA (SME-CA) were 130 ± 5.92 nm, -25.7 ± 6.00 mV, and 99.5 ± 0.25%, respectively. The area under the curve from 0 h to termination time (AUC(0-t)) of SME-CA showed a significantly higher value than that of CA (589 ± 59.2 vs 375 ± 83.5 ng h/L, P < 0.01). Tissue distribution study showed various changes; among them, a 27% higher concentration was found in brain tissue when using SME-CA at 15 min after administration. For the efficacy evaluation, SME-CA exhibited 8- and 11-fold antitumor activity in the depression of HeLa and A549 cell lines with the IC50 decreasing to 0.003 and 0.001 mmol/L, respectively. The LD50 values of CA and SME-CA in mice were 74.8 and 125 mg/kg, suggesting increased safety from the new formulation. The new formulation exhibited lower toxicity, higher antitumor activity, and a more satisfactory pharmacokinetic property, which displayed great potential for future pharmacological application.

Engineering Biomaterial-Drug Conjugates for Local and Sustained Chemotherapeutic Delivery

The standard of care for cancer patients includes surgical resection, radiation, and chemotherapy with cytotoxic chemotherapy drugs usually part of the treatment. However, these drugs are commonly associated with cardiotoxicity, ototoxicity, nephrotoxicity, peripheral neuropathy, and myelosuppression. Strategies to deliver cytotoxic chemotherapy drugs while reducing secondary toxicity and increasing tumor dosing would therefore be desirable. This goal can be achieved through the use of controlled release drug carrier systems. The aim of this review is to provide an overview of clinically used drug carrier systems and recently developed approaches for drug-biomaterial conjugation.

Natural alkaloids: basic aspects, biological roles, and future perspectives

Natural products have gained popularity worldwide for promoting healthcare, as well as disease prevention. Alkaloids are important chemical compounds that serve as a rich reservoir for drug discovery. Several alkaloids isolated from natural herbs exhibit antiproliferation, antibacterial, antiviral, insecticidal, and antimetastatic effects on various types of cancers both in vitro and in vivo. This paper focuses on the naturally-derived alkaloids such as berberine, matrine, piperine, fritillarine, and rhynchophylline, etc., and summarizes the action mechanisms of these compounds. Based on the information in the literature that is summarized in this paper, the use of alkaloids as drugs is very promising, but more research and clinical trials are necessary before final recommendations on specific alkaloids can be made. Following this, it is hoped that as a result of this review, there will be a greater awareness of the excellent promise that natural alkaloids show for use in the therapy of diseases.

Induction and mechanism of HeLa cell apoptosis by 9-oxo‑10, 11-dehydroageraphorone from Eupatorium adenophorum

9-Oxo-10, 11-dehydroageraphorone (euptox A), a cadenine sesquiterpene, is the main toxin from Eupatorium adenophorum. The aim of the present study was to examine the induction and mechanism of HeLa cell apoptosis by euptox A. The apoptosis‑inducing effect of the euptox A on HeLa cells was examined by MTT assay. The underlying mechanism was analyzed by flow cytometry and quantitative PCR. Flow cytometry results suggested that euptox A effectively inhibited the proliferation of HeLa cells, arrested the cell cycle transition from S to G2/M phase, did not continue to complete the cell cycle activity (mainly from 4 times and mitosis), and induced cell proliferation. The RT-qPCR detection results showed that euptox A induced apoptosis by improving the gene expression level of apoptotic proteases such as caspase-10 in HeLa cells. Its mechanism of action was associated with the upregulation of apoptotic gene expression and arresting of the cell cycle.

Scopine as a novel brain-targeting moiety enhances the brain uptake of chlorambucil

The blood brain barrier (BBB) represents the biggest challenge for therapeutic drugs to enter the brain. In our study, we selected chlorambucil (CHL), an alkylating agent, as the model therapeutic agent, and used scopine as a novel brain-targeting moiety. Here, we synthesized Chlorambucil-Scopine (CHLS) prodrug and evaluated its brain-targeting efficacy. The tissue distribution study after i.v. injection revealed that the AUC0-t and Cmax of CHLS in the brain were 14.25- and 12.20-fold of CHL, respectively. Specifically, CHLS accumulated in bEnd.3 and C6 cells in an energy-dependent manner. In C6 cells, superior anti-glioma activity with a significantly decreased IC50 of 65.42 nM/mL was observed for CHLS compared to CHL (IC50 > 400 nM/mL). The safety evaluation, including acute toxicity, pathology, and hematology study, showed minimal toxicity toward nontargeting tissues, and also reached a lower systemic toxicity at 5 mg/kg (i.v.). Our results suggested that scopine is a potential brain-targeting moiety for enhancing the brain uptake efficiency of CHL.

Preparation and Microbiological Evaluation of Amphiphilic Kanamycin-Lipoamino Acid Ion-Pairs

Amphiphilic ion-pairs of kanamycin (KAN) were prepared by evaporation of a water-ethanol co-solution of KAN base and a lipoamino acid bearing a 12-carbon atoms alkyl side chain (LAA12), at different molar ratios. Infrared spectroscopy confirmed the structure of ion-pairs, while differential scanning calorimetry (DSC) and powder X-ray diffractometry (PXRD) studies supported the formation of new saline species with a different crystalline structure than the starting components. The solubility pattern shown in a range of both aqueous and organic solvents confirmed that the ion-pairs possess an amphiphilic character. The LAA12 counter-ion showed not to improve the antibacterial activity of KAN, suggesting that such chemical strategy is not able to favor the penetration of this drug inside the bacteria cells. Nevertheless, a slight improving, i.e., a one-fold dilution, was observed in E. coli. The present study can also serve as the basis for a further evaluation of LAA ion-pairing of antibiotics, as a means to improve the loading of hydrophilic drugs into lipid-based nanocarriers.