Subcutaneous angiogenesis induced by transdermal delivery of gel-in-oil nanogel dispersion.

Subcutaneous transplantation aims to enhance the growth and functionality of transplanted cells for therapeutic outcomes in tissue engineering. However, the limited subcutaneous vascular network poses a challenge. Conventional methods involve co-transplantation with endothelial cells or angiogenic scaffold implantation, but they have drawbacks like tissue inflammation, compromised endothelial cell functionality, and the risk of repeated scaffold transplantation. Effective techniques are needed to overcome these challenges. This study explores the potential of G/O-NGD, a gel-in-oil nanogel dispersion, as a transdermal carrier of proliferative factors to promote angiogenesis in subcutaneous graft beds before cell transplantation. We observed robust subcutaneous angiogenesis by delivering varying amounts of bFGF using the G/O-NGD emulsion. Quantitative analysis of several parameters confirmed the efficacy of this method for building a subcutaneous vascular network. G/O-NGD is a biodegradable material that facilitates localized transdermal delivery of bFGF while maintaining its activity. The findings of this study have significant implications in both medical and industrial fields.

Prevention and Repair of Ultraviolet B-Induced Skin Damage in Hairless Mice via Transdermal Delivery of Growth Factors Immobilized in a Gel-in-Oil Nanoemulsion.

Ultraviolet (UV) radiation from the sun or artificial sources is one of the primary causes of skin damage, including sunburns, tanning, erythema, and skin cancer. Among the three different types of UV rays, UVB rays have a medium wavelength that can penetrate the epidermal layer of the skin, resulting in sunburn, suntan, blistering, and melanoma in case of chronic exposure. This study aimed to evaluate the preventive and therapeutic effects of a gel-in-oil nanogel dispersion (G/O-NGD) as a transdermal delivery biomolecular carrier for skin damage caused by UVB light. The efficacy of this carrier against UVB-induced skin damage was investigated in vivo by delivering different growth factors (GFs) encapsulated in a G/O-NGD. Artificial UVB light was used to induce skin damage in nude mice, followed by the transdermal application of five GF [vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), transforming growth factor (TGF)-1, and insulin-like growth factor (IGF)-α]-immobilized G/O-NGD. Among these GFs, VEGF and bFGF promoted angiogenesis, while EGF, TGF-1, and IGF-α promoted the repair and regeneration of damaged cells. The results showed that G/O-NGD was superior to heparin-immobilized G/O-NGD in reducing UVB-induced skin damage, such as erythema, epidermal water reduction, inflammation, and dermis thickening. In addition, G/O-NGD could prevent and treat abnormal follicle proliferation caused by UVB rays and exhibited potential to repair lipid glands. Overall, our results demonstrate the potential of G/O-NGDs for the treatment of UVB-induced skin damage.

Delivery of Hydrophobic Drugs to the Posterior Ocular Region by Gel-in-Water Nanoemulsion.

Purpose: The aim of this study was to develop a nanogel emulsion as a minimally invasive, safe, and effective treatment alternative for posterior ocular diseases. Methods: A gel-in-water (G/W) nanoemulsion was developed by ultrasonication using beeswax as an organogelator. Different physicochemical properties were evaluated along with particle size analysis by dynamic light scattering. In vitro biocompatibility of G/W nanoemulsion using rat hepatocytes and human umbilical vein endothelial cells (HUVECs) and in vivo corneal permeability as eye drops were investigated. Results: The nanogel emulsion was monodispersed with a polydispersity index and particle diameter of approximately 0.2 and 200 nm, respectively. The zeta potential value of -8.1 mV suggested enhanced stability and improved retinal permeability of nanoparticles. The prepared nanoemulsion was found to be biocompatible with hepatocytes and HUVECs in vitro. Moreover, in vivo study demonstrated high permeability of G/W nanoemulsion to the retinal layer with no ocular irritation. Conclusions: G/W nanoemulsions have the potential for topical drug delivery in the posterior eye segment with maximum therapeutic efficacy. Translational Relevance: Organogel nanodispersion is a new concept to deliver hydrophobic drugs to the posterior segment of eyes as a novel drug delivery system.

Development of a gel-in-oil emulsion as a transdermal drug delivery system for successful delivery of growth factors.

Growth factors (GFs) are indispensable in regenerative medicine because of their high effectiveness. However, as GFs degenerate easily, the development of a suitable carrier with improved stability for GFs is necessary. In this study, we developed a gel-in-oil (G/O) emulsion technology for the transdermal delivery of growth factors. Nanogel particles prepared with heparin-immobilized gelatin that can bind growth factors were dispersed in isopropyl myristate. The particle size of the G/O emulsion could be controlled by changing the surfactant concentration, volume ratio of the water phase to the oil phase, and gelatin concentration. In vitro skin penetration studies showed better penetration through the stratum corneum of fluorescent proteins containing G/O emulsions than of the aqueous solution of GF. Similarly, an in vivo study showed an angiogenesis-inducing effect after transdermal application of GF-immobilized G/O emulsion. Angiogenesis in mice was confirmed owing to both an increased blood vessel network and higher hemoglobin content in the blood. Therefore, the G/O emulsion could be a promising carrier for GFs with better stability and can effectively deliver GFs at the target site.

Randomized study of intravesical pirarubicin chemotherapy with low and intermediate-risk nonmuscle-invasive bladder cancer in Japan: Comparison of a single immediate postoperative intravesical instillation with short-term adjuvant intravesical instillations after transurethral resection.

PURPOSE: The objective of this study was to evaluate the efficacy, defined by the 3-year tumor recurrence-free survival rate, of intravesical chemotherapy using pirarubicin (THP) in patients with low or intermediate-risk nonmuscle-invasive bladder cancer (NMIBC). PATIENTS AND METHODS: Between October 2010 and January 2015, 206 patients were enrolled, and finally 113 were randomized to receive either a single immediate postoperative intravesical instillation of THP (30 mg) (Group A), or 8 additional weekly intravesical instillations of THP (30 mg) after a single postoperative instillation (Group B). The patients were examined by performing cystoscopy and urine cytology every 3 months after transurethral resection to determine bladder tumor recurrence. The primary endpoint was 3-year-recurrence-free survival rate. RESULTS: All 113 patients were bacillus Calmette-Guérin (BCG)-naïve. The 3-year recurrence free survival rate was 63.7% for Group A and 85.3% for Group B (log-rank test, P = .0070). In patients with intermediate recurrence risk, the 3-year recurrence-free survival rate was 63.4% in Group A and 86.1% in Group B (log-rank test, P = .0036). Cox regression analysis revealed that only additional instillation of THP was a significant independent factor for recurrence-free rate in patients with intermediate risk. No patient with progression was noted during this period. Frequent adverse effects (AEs) were frequent urination and micturition pain, and no severe AEs (Grade 3 or more) occurred. CONCLUSION: Additional instillation of THP (30 mg) weekly for 8 weeks reduced the risk of tumor recurrence without severe AEs in BCG-naïve NMIBC patients with intermediate risk.