Skin healing effects of an innovative polymer-based oil Nigella sativa: a rabbit model experimental study.

OBJECTIVE: Natural wound dressings composed of gelatin (GEL) and chitosan (CH) impregnated with bioactive compounds (Nigella sativa oil) were prepared and characterized to evaluate their potential application. MATERIALS AND METHODS: The formulated composite was subjected to γ-irradiation. In vitro, the ferric-reducing antioxidant power (FRAP) assay and antibiofilm activities were evaluated. In vivo, the tissue wound-healing process was studied by applying GEL-CH-Nigella in dorsal skin rabbit tissue. On days 7 and 14, the biochemical biomarker and histological analysis were determined. RESULTS: At 10 kGy, FRAP assays exhibited the highest antioxidant activity (380 mmol/kg). A significant inhibition of anti-biofilm activity was observed against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) (p<0.01). Fourteen days post-surgery, a significant reduction in thiobarbituric acid-reactive compounds (TBARs) was observed compared to the GEL-CH group. Concerning oxidative stress status, GEL-CH-Nigella significantly improved superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities. A histological analysis revealed that GEL-CH-Nigella accelerated wound closure and improved collagenisation and enhanced epidermal tissue thickness. CONCLUSIONS: These results indicate that GEL-CH-Nigella wound dressing is a promising biomaterial for engineered tissue.

Biological therapy of strontium-substituted bioglass for soft tissue wound-healing: responses to oxidative stress in ovariectomised rats.

New synthetic biomaterials are constantly being developed for wound repair and regeneration. Bioactive glasses (BG) containing strontium have shown successful applications in tissue engineering account of their biocompatibility and the positive biological effects after implantation. This study aimed to assess whether BG-Sr was accepted by the host tissue and to characterize oxidative stress biomarker and antioxidant enzyme profiles during muscle and skin healing. Wistar rats were divided into five groups (six animals per group): the group (I) was used as negative control (T), after ovariectomy, groups II, III, IV and V were used respectively as positive control (OVX), implanted tissue with BG (OVX-BG), BG-Sr (OVX-BG-Sr) and presented empty defects (OVX-NI). Soft tissues surrounding biomaterials were used to estimate superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and malondialdehyde (MDA) concentration. Our results show that 60 days after operation, treatment of rats with BG-Sr significantly increased MDA concentration and caused an increase of SOD, CAT and GPx activities in both skin and muscular tissues. BG-Sr revealed maturation of myotubes followed a normal appearance of muscle regenerated with high density and mature capillary vessels. High wound recovery with complete re-epithelialization and regeneration of skin was observed. The results demonstrate that the protective action against reactive oxygen species (ROS) was clearly observed in soft tissue surrounding BG-Sr. Moreover, the potential use of BG-Sr rapidly restores the wound skin and muscle structural and functional properties. The BG advantages such as ion release might make BG-Sr an effective biomaterial choice for antioxidative activity.