Development of BDNF/NGF/IKVAV Peptide Modified and Gold Nanoparticle Conductive PCL/PLGA Nerve Guidance Conduit for Regeneration of the Rat Spinal Cord Injury.

Spinal cord injuries are very common worldwide, leading to permanent nerve function loss with devastating effects in the affected patients. The challenges and inadequate results in the current clinical treatments are leading scientists to innovative neural regenerative research. Advances in nanoscience and neural tissue engineering have opened new avenues for spinal cord injury (SCI) treatment. In order for designed nerve guidance conduit (NGC) to be functionally useful, it must have ideal scaffold properties and topographic features that promote the linear orientation of damaged axons. In this study, it is aimed to develop channeled polycaprolactone (PCL)/Poly-D,L-lactic-co-glycolic acid (PLGA) hybrid film scaffolds, modify their surfaces by IKVAV pentapeptide/gold nanoparticles (AuNPs) or polypyrrole (PPy) and investigate the behavior of motor neurons on the designed scaffold surfaces in vitro under static/bioreactor conditions. Their potential to promote neural regeneration after implantation into the rat SCI by shaping the film scaffolds modified with neural factors into a tubular form is also examined. It is shown that channeled groups decorated with AuNPs highly promote neurite orientation under bioreactor conditions and also the developed optimal NGC (PCL/PLGA G1-IKVAV/BDNF/NGF-AuNP50 ) highly regenerates SCI. The results indicate that the designed scaffold can be an ideal candidate for spinal cord regeneration.

Design of IKVAV peptide/gold nanoparticle decorated, micro/nano-channeled PCL/PLGA film scaffolds for neuronal differentiation and neurite outgrowth.

In the field of neural tissue engineering, intensive efforts are being made to develop tissue scaffolds that can support an effective functional recovery and neural development by guiding damaged axons and neurites. Micro/nano-channeled conductive biomaterials are considered a promising approach for repairing the injured neural tissues. Many studies have demonstrated that the micro/nano-channels and aligned nanofibers could guide the neurites to extend along the direction of alignment. However, an ideal biocompatible scaffold containing conductive arrays that could promote effective neural stem cell differentiation and development, and also stimulate high neurite guidance has not been fully developed. In the current study, we aimed to fabricate micro/nano-channeled polycaprolactone (PCL)/Poly-d,l-lactic-co-glycolic acid (PLGA) hybrid film scaffolds, decorate their surfaces with IKVAV pentapeptide/gold nanoparticles (AuNPs), and investigate the behavior of PC12 cells and neural stem cells (NSCs) on the developed biomaterial under static/bioreactor conditions. Here we show that channeled groups decorated with AuNPs highly promote neurite outgrowth and neuronal differentiation along linear lines in the presence of electrical stimulation, compared with the polypyrrole (PPy) coating, which has been used traditionally for many years. Hopefully, this newly developed channeled scaffold structure (PCL/PLGA-AuNPs-IKVAV) could help to support long-distance axonal regeneration and neuronal development after different neural damages.

Azelaic acid loaded chitosan and HPMC based hydrogels for treatment of acne: formulation, characterization, in vitro-ex vivo evaluation.

In this study, hydrogels containing azelaic acid were developed using chitosan or HPMC (1-7%) for local treatment of acne vulgaris. Physicochemical properties such as viscosity, pH and mechanical properties were evaluated. In vitro release and ex vivo permeability studies were performed using the Franz diffusion cell system. The pH of the hydrogels was highly compatible with the skin pH and varied between 4.38 and 5.84. The cumulative release percentages of the hydrogels at the end of 6 hours were 65-78%, whereas the marketed product yielded 50% drug release. According to the ex vivo permeability results, azelaic acid accumulated in the skin was found to be 9.38 ± 0.65% (marketed cream), 19.53 ± 1.06% (K3), 10.96 ± 1.91% (H6). The antiacne studies with Cutibacterium acnes revealed that K3 (29.45 ± 0.95) and H6 (32.35 ± 0.15) had higher inhibition zones compared to the marketed cream (24.50 ± 0.90). Additionally, the gels were found to be highly stable as a result of the stability studies for 6 months. Among the hydrogels that were prepared based on experimental findings, K3 (3% Chitosan) and H6 (6% HPMC) represented elevated in vitro release profile, higher permeability and increased antiacne activity. The findings of this research suggest that the developed hydrogels might be an alternative to the marketed product.

Identifying probiotic characteristics of Lactobacillus crispatus isolated from the vagina

Lactobacilli prevent overproduction of pathogenic microorganisms and contribute protecting vaginal microbiota. Many probiotic microorganisms are categorized as Lactic Acid Bacteria. In this study, it was aimed identifying probiotic characteristics of Lactobacillus crispatus isolated from the vagina of a healthy woman. For this purpose, lactic acid, hydrogen peroxide and proteolytic activity quantities and auto-aggregation, co-aggregation and hydrophobicity abilities of Lactobacillus crispatus, which has been isolated and identified by 16s rRNA sequence analysis, were determined. Additionally, bile salt and acid resistance, along with antibiotic susceptibility of Lactobacillus crispatus were analyzed by the end of 3 hours. Lactic acid, hydrogen peroxide and proteolytic activity quantities of Lactobacillus crispatus were measured 2.275%, 0.334±0.075 µg/mL and 2.131±0,000 mg/mL respectively. The findings include existence of co-aggregation and auto-aggregation ability, but not hydrophobicity. By the end of 3 hours, the viability was preserved in 0.1% and 0.3% bile salt medium and, at pH 3. L. crispatus exhibited resistance to methicillin, metronidazole, oxacillin, and sulfamethoxazole + trimethoprim, but the bacteria exhibited susceptibility to tested the other antibiotics. This study will make an important contribution to the literature about probiotic characteristics of L. crispatus and our strain isolated from the vagina might be considered as a candidate probiotic.