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Gene therapy is one of the recent approaches in treatment of hepatocellular carcinoma (HCC). Development of a vector or vehicle that can selectively and efficiently deliver the gene to target cells with minimal toxicity is an urgent demand. In the present study, phosphatase and tensin homolog (PTEN) and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) genes were loaded to zein nanoparticles (ZNPs). The formulated PTEN and TRAIL-loaded ZNPs were tested for their in vitro and in vivo potential antitumor efficacy using liver tumor cells (HepG2) and HCC-induced rats as animal model. Also, mRNA expression of p53, VGEF and MMP-2 were carried out as markers of apoptosis, angiogenesis and metastasis in animal liver tissues. The results of the study showed that both PTEN and TRAIL-loaded ZNPs proved anti-proliferative activity against HepG2 cell lines with IC50 values of 0.09, 0.25 µg/ml, respectively. In vivo assay confirmed decrease in mRNA expression of both VEGF and MMP-2 with increased in P53 expression level in liver tissues of the treated animals. Therefore, authors introduced new integration between gene therapy and nanotechnology in the form of PTEN and TRAIL-loaded ZNPs that proved potential to be used in gene therapy for the treatment of HCC. [ABSTRACT FROM AUTHOR]

Context:A microbiological multidistrict-based survey from different Egyptian governorates was conducted to determine the most prevalent causative agents of ocular infections in the Egyptian population. Antibiotic sensitivity testing was then performed to identify the most potent antimicrobial agent. Vancomycin (VCM) proved the highest activity against gram-positive Staphylococcusbacteria, which are the most commonly isolated causative agents of ocular infection. However, topically applied VCM suffers from poor ocular bioavailability because of its high molecular weight and hydrophilicity.Objective:The aim of the present study was to develop VCM-loaded solid lipid nanoparticles (SLNs) using water-in-oil-in-water (W/O/W) double emulsion, solvent evaporation technique to enhance ocular penetration and prolong ophthalmic residence of VCM.Method:Two consecutive full factorial designs (24followed by 32) were adopted to study the effect of different formulation and process parameters on SLN formulation. The lipid type and structure, polyvinyl alcohol (PVA) molecular weight and concentration, sonication time, as well as lipid:drug ratio were studied as independent variables. The formulated SLN formulae were evaluated for encapsulation efficiency (EE%), particle size (PS), and zeta potential as dependent variables.Results:The statistically-optimized SLN formula (1:1 ratio of glyceryltripalmitate:VCM with 1% low molecular weight PVA and 1 min sonication time) had average PS of 277.25 nm, zeta potential of −20.45, and 19.99% drug encapsulation. Scanning and transmission electron micrographs showed well-defined, spherical, homogenously distributed particles.Conclusion:The present study suggests that VCM incorporation into SLNs is successfully achievable; however, further studies with different nanoencapsulation materials and techniques would be valuable for improving VCM encapsulation. [ABSTRACT FROM AUTHOR]

Hypericin (HYP), a natural photosensitizer, has powerful photo-oxidizing ability, tumor-seeking characteristics, and minimal dark toxicity; nevertheless, it has proven high lipid solubility compared to its sparingly water soluble nature. Therefore, its formulation into solid lipid nanoparticles (SLNs) has attracted increasing attention as a potential drug-delivery carrier. Two HYP-loaded SLNs formulations were prepared utilizing microemulsion-based technique. Thereafter, the physicochemical properties of the formulations were investigated and evaluated. HYP-loaded SLNs showed spherical shape with mean particle size ranging from 200-300 nm for both formulations (FA and FB). The encapsulation efficiencies reached above 80% and FA showed significant higher encapsulation than FB ( P < 0.05), also, the thermal analysis using differential scanning calorimetry (DSC) indicated good compatibility between hypericin and lipids forming the cores in both formulations. Spectroscopic measurements of the photostability study showed that hypericin encapsulation into SLNs improved its photostability, compared to free HYP in 0.1% ethanolic solution. However, photocytotoxicity studies on HepG2 cells revealed an evident inhibition of the photodynamic efficacy of HYP-loaded SLNs, compared to free HYP. In conclusion, although the elevated entrapment efficiency of HYP into SLNs increased its photostability, it decreased its phototoxicity which might be due to the quenching deactivation of HYP molecules resulting from SLN compactness and thickness structure. [ABSTRACT FROM AUTHOR]

Oral Almotriptan maleate (ALM) is used in the treatment of migraine; however, due to its extreme aqueous solubility, shows poor penetration and lesser concentration in the brain thus requiring frequent oral dosing. Being flexible and lipophilic in nature, nanostructured lipid carriers (NLCs) represent a promising tool in delivering therapeutic substances to the brain. This investigation is meant to explore the capability of mucoadhesive chitosan-coated NLCs to efficiently deliver ALM to the brain through the nasal route as a non-invasive alternative route for targeting the central nervous system (CNS). D-optimal design was adopted and thirteen different formulae were prepared using hot homogenization and ultrasonication technique; where an accurate amount of the almotriptan was added to the molten lipid mixture followed by the addition of the heated aqueous phase under stirring, then the mixture was subjected to homogenization and ultrasonication. The prepared systems were then assessed for their particle size, PDI (polydispersity index), zeta potential (ZP), and entrapment efficiency (EE). The optimized selected formula; F1; composed of 50/50 Compritol/Labrafil and a co-mixture of 2:1 tween 80: Lauroglycol all coated in chitosan, showed a PS of 255 nm, PDI 0.27, ZP 34.1 mV, and 80% EE. A bi-phasic in vitro drug release pattern was obtained, enhanced mucoadhesive property and ex-vivo permeability through sheep nasal mucosa were attained. The In vivo studies performed on albino rabbits showed significantly higher C max results in plasma of the optimized ALM-NLC (1.54 μg/mL) compared to those of IN ALM solution (0.25 μg/mL) and ALM oral tablet market product (0.58 μg/mL). Brain C max were found to be 3.64 μg/mL, 0.5 μg/mL and 0.48 μg/mL for IN ALM-NLC, oral ALM market product and, IN ALM solution, respectively. Histopathological examination marked the formula as safe. [ABSTRACT FROM AUTHOR]

• Chitosan adsorbed on nanodiamonds and reversed their surface charge from negative to positive side. • Further dextran sulphate coating rendered drug release alkaline-triggered. • TPP- treated, but not dextran sulphate, nanoparticles displayed augmented cytotoxicity. • Chitosan-coated nanodiamonds enhanced doxorubicin retention in bovine urinary bladder. Nanodiamonds (NDs) are an emerging delivery system with a massive surface area qualifying them for efficient loading with various drugs. However, NDs easily scavenge ions upon mixing with physiological media leading to rapid aggregation. Herein, chitosan was employed to endue steric stabilization to NDs and confer adhesiveness to the particles improving their retention in the urinary bladder. The effect of chitosan molecular weight and pH on the particle size and surface charge of chitosan-coated doxorubicin-loaded NDs (Chi-NDX) was investigated. Selected formula exhibited high drug loading efficiency (>90 %), small particle size (<150 nm), good colloidal stability, acid-favored drug release but limited stability in cell culture media. After further stabilization with TPP or dextran sulfate, selected TPP-treated formula displayed more potent cytotoxic effect compared with free doxorubicin and uncoated nanoparticles, and higher drug retention in ex vivo bovine bladder. Therefore, TPP-Chi-NDX is suggested as a promising system for mucosal anticancer delivery. [ABSTRACT FROM AUTHOR]

Ocular topically applied Vancomycin (VCM) suffers poor bioavailability due to its high molecular weight and hydrophilicity. In the present investigation, VCM-loaded polymeric nanoparticles (PNPs) were developed aiming to enhance its ocular bioavailability through prolonging its release pattern and ophthalmic residence. PNPs were prepared utilizing double emulsion (W/O/O), solvent evaporation technique. 2 3 × 4 1 full factorial design was applied to evaluate individual and combined influences of polymer type, Eudragit® RS100, sonication time, and Span®80 concentration on PNPs particle size, encapsulation efficiency, and zeta potential. Further, the optimized formulae were incorporated in 1% Carbopol®-based gel. In - vivo evaluation of the optimized formulae was performed via Draize test followed by microbiological susceptibility testing on albino rabbits. Results revealed successful formulation of VCM-loaded PNPs was achieved with particle sizes reaching 155 nm and up to 88% encapsulation. Draize test confirmed the optimized formulae as non-irritating and safe for ophthalmic administration. Microbiological susceptibility testing confirmed prolonged residence, higher C max. with more than two folds increment in the AUC (0.25–24) of VCM-PNPs over control groups. Thus, VCM-loaded PNPs represent promising carriers with superior achievements for enhanced Vancomycin ophthalmic delivery over the traditional use of commercially available VCM parenteral powder after constitution into a solution by the ophthalmologists. [ABSTRACT FROM AUTHOR]