Fabrication, characterization and application of novel nanoemulsion polyvinyl alcohol/chitosan hybrid incorporated with citral for healing of infected full-thickness wound

The effects of bioactive glass hydrogel coated with hyaluronic acid-Pluronic F-127 conjugates containing silver nanoparticles for accelerating of infected wounds healing

Antimicrobial resistance has forced researchers to produce new dressings for the treatment of infected wounds. Tissue engineering based on biomaterials is used to accelerate the wound healing process. The purpose of this study was to examine the effects of bioactive glass (BG) hydrogel coated with hyaluronic acid (HA)-Pluronic F-127 (PLF-127) conjugates containing silver nanoparticles (AgNPs) for healing the infected wounds. HA/BG, PL&HA/BG and PL&HA/BG-AgNPs formulations were designed and their properties were evaluated for application in the wound healing process. Safety and antibacterial properties of formulations were also evaluated. These were applied for the treatment of infected wounds and their efficiencies were assessed by measuring wound contraction, total bacterial count, pathological parameters and the expression of positive cells of cyclin-D1, c-Myc, WNT-1, B-Catenin, and COL-1A. The synthesized thermally reversible hydrogels demonstrated sol-gel transition, indicating the gels' potential as injectable hydrogels. These exhibited antibacterial properties and safety. The PL&HA/BG-AgNPs, PL&HA/BG and HA/BG hydrogels showed greatest wound healing activities, respectively and could compete with Polysporin® due to their effects on total bacterial count and modulation in increasing the expressions of B-Catenin, COL-1A, cyclin-D1 and c-Myc. In sum, PL&HA/BG-AgNP hydrogels are good candidate for accelerating the wound healing process and as alternatives for antibiotics in the treatment of infected wounds.

Effect of PCL nanofiber mats coated with chitosan microcapsules containing cinnamon essential oil for wound healing

INTRODUCTION

Cinnamon is one of the most common spices that has been studied for its anti-inflammatory, antioxidant, and antibacterial properties in wound healing. The purpose of this study was to evaluate the effectiveness of polycaprolactone nanofiber mats coated with chitosan microcapsules loaded with cinnamon essential oil in wound healing.

MATERIAL AND METHODS

For this purpose, chitosan microcapsules containing cinnamon essential oil (µCS-CiZ) were prepared by ion gelation and PCL nanofibers by electrospinning. The size of the µCS-CiZ and the morphology of nanofibers were evaluated by DLS and FESEM methods. In order to evaluate wound healing, 48 rats in 4 groups of Control, µCS-CiZ, PCL, and PCL + µCS-CiZ and were examined on days 7, 14, and 21 in terms of macroscopy (wound closure rate) and histology (edema, inflammation, vascularity, fibrotic tissue, and re-epithelialization).

RESULTS

The particle size of the µCS-CiZ and the diameter of the nanofibers were estimated at about 6.33 ± 1.27 μm and 228 ± 33 nm, respectively. On day 21, both µCS-CiZ and PCL groups showed a significant decrease in wound size compared to the control group (P < 0.001). The PCL + µCS-CiZ group also showed a significant decrease compared to the µCS-CiZ (P < 0.05) and PCL groups (P < 0.05). Histological results showed further reduction of edema, inflammation, and vascularity in granulation tissue and appearance of moderate to marked fibrotic tissue in PCL + µCS-CiZ group compared with the other groups.

CONCLUSION

The results of the study showed that the combined use of PCL + µCS-CiZ indicates a synergistic effect on improving wound healing.

Citral Modulates MMP-2 and MMP-9 Activities on Healing of Gastric Ulcers Associated with High-Fat Diet-Induced Obesity

Obesity causes low-grade inflammation that results in the development of comorbidities. In people with obesity, exacerbation of gastric lesion severity and delayed healing may aggravate gastric mucosal lesions. Accordingly, we aimed to evaluate the citral effects on gastric lesion healing in eutrophic and obese animals. C57Bl/6 male mice were divided into two groups: animals fed a standard diet (SD) or high-fat diet (HFD) for 12 weeks. Gastric ulcers were induced using acetic acid (80%) in both groups. Citral (25, 100, or 300 mg/kg) was administered orally for 3 or 10 days. A vehicle-treated negative control (1% Tween 80, 10 mL/kg) and lansoprazole-treated (30 mg/kg) were also established. Lesions were macroscopically examined by quantifying regenerated tissue and ulcer areas. Matrix metalloproteinases (MMP-2 and -9) were analyzed by zymography. The ulcer base area between the two examined periods was significantly reduced in HFD 100 and 300 mg/kg citral-treated animals. In the 100 mg/kg citral-treated group, healing progression was accompanied by reduced MMP-9 activity. Accordingly, HFD could alter MMP-9 activity, delaying the initial healing phase. Although macroscopic changes were undetectable, 10-day treatment with 100 mg/kg citral exhibited improved scar tissue progression in obese animals, with reduced MMP-9 activity and modulation of MMP-2 activation.