Resveratrol-coated chitosan mats promote angiogenesis for enhanced wound healing in animal model

BACKGROUND

Growing incidences of chronic wounds recommend the development of optimal therapeutic wound dressings. Electrospun nanofibers have been considered to show potential wound healing properties when accompanied by other wound dressing materials. This study aimed to explore the potential role of Chitosan (CS) nanofibrous mats coated with resveratrol (RS) as an antioxidant and pro-angiogenic agent in rat models of skin wound healing.

METHODS

Electrospun chitosan/polyethylene oxide (PEO) nanofibers were prepared using electrospinning technology and coated by 0.05 and 0.1 mg.ml resveratrol named as (CS/RS 0.05) and (CS/RS 0.1), respectively. The scaffolds were characterized physiochemically such as in vitro release study, TGA, FTIR spectroscopy analysis, biodegradability, and human dermal fibroblast seeding assay. The scaffold was subsequently used in vivo as a skin substitute on a rat skin wound model.

RESULTS

In vitro tests revealed that all scaffolds promoted cell adhesion and proliferation. However, more cell viability was observed in CS/RS 0.1 scaffold. The biocompatibility of the scaffolds was validated by MTT assay, and the results did not show any toxic effects on human dermal fibroblasts. It was observed that RS-coated scaffolds had the ability to release RS in a controlled manner. In in vivo tests CS/RS 0.1 scaffold had the greatest impact on the healing process by improving the neodermis formation and modulated inflammation in wound granulation tissue. Histological analysis revealed enhanced vascular endothelial growth factor expression, epithelialization and increased depth of wound granulation tissue.

CONCLUSIONS

The RS-coated CS/PEO nanofibrous scaffold accelerates wound healing and may be useful as a dressing for cell transfer and clinical skin regeneration.

Incorporation of Resveratrol-Hydroxypropyl-β-Cyclodextrin Complexes into Hydrogel Formulation for Wound Treatment

Resveratrol could be applied in wound healing therapies because of its antioxidant, anti-inflammatory and antibacterial effects. However, the main limitation of resveratrol is its low aqueous solubility. In this study, resveratrol was included in hydroxypropyl-β-cyclodextrin complexes and further formulated in Pluronic F-127 hydrogels for wound treatment therapy. IR-spectroscopy and XRD analysis confirmed the successful incorporation of resveratrol into complexes. The wound-healing ability of these complexes was estimated by a scratch assay on fibroblasts, which showed a tendency for improvement of the effect of resveratrol after complexation. The antimicrobial activity of resveratrol in aqueous dispersion and in the complexes was evaluated on methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Candida albicans strains. The results revealed a twofold decrease in the MIC and stronger inhibition of the metabolic activity of MRSA after treatment with resveratrol in the complexes compared to the suspended drug. Furthermore, the complexes were included in Pluronic hydrogel, which provided efficient drug release and appropriate viscoelastic properties. The formulated hydrogel showed excellent biocompatibility which was confirmed via skin irritation test on rabbits. In conclusion, Pluronic hydrogel containing resveratrol included in hydroxypropyl-β-cyclodextrin complexes is a promising topical formulation for further studies directed at wound therapy.

In Vitro Antioxidant and Fibroblast Migration Activities of Fractions Eluded from Dichloromethane Leaf Extract of Marantodes pumilum

(1) The complexity of diabetes and diabetic wound healing remains a therapeutic challenge because proper and systematic wound care and management are essential to prevent chronic microbial infection and mechanical damage to the skin. Marantodes pumilum, locally known as 'Kacip Fatimah', is an herb that has been previously reported to possess anti-inflammatory, analgesic, antinociceptive and antipyretic properties. The current study aims to assess the antioxidant and fibroblast cell migration activities of the fractions eluded from the dichloromethane extract of M. pumilum leaves. (2) The total antioxidant capacity of M. pumilum was assessed using the total proanthocyanidins and phosphomolybdenum assays, while DPPH, nitric oxide, hydrogen peroxide and superoxide free radical scavenging assays were tested to determine the antioxidant potential of M. pumilum. An in vitro scratch wound assay was performed to measure the fibroblast cell migration rate using normal and insulin-resistant human dermal fibroblast cells. (3) All M. pumilum fractions exhibited good antioxidant and fibroblast cell migration activity, among which fractions A and E displayed the greatest effect. (4) M. pumilum's fibroblast migration activity could be attributed to its strong antioxidant properties along with its previously reported properties.

Comparison of Deep Partial Thickness Burns Wound Healing with Resveratrol Gel and Paraffin Gauze in Wistar Rats

BACKGROUND: Various modalities of wound care in burn cases are offered, but there is no standard algorithm used. Paraffin gauze dressing, as one of the commonly used dressings, is considered to have many shortcomings. Resveratrol, a stilbenoid derived from plants, is reported to have a role in wound healing process, it has the potential to be one of the modalities for treating burns. This study aims to strengthen studies on the role of resveratrol in wound healing process, especially in burns compared with paraffin gauze. AIM: This study conducted to prove that resveratrol gel more superior than paraffin gauze in deep partial thickness burns healing process. METHODS: This research is a laboratory experimental study with a post-test only design, simple randomized, and single blind. A sample of 32 Wistar rats with deep partial thickness burns was divided into four control groups and four treatment groups. Control groups were treated using paraffin gauze. Treatment groups were treated using resveratrol gel. Group 1 of each group was assessed for epithelialization. Angiogenesis, fibroblasts, and collagen deposition was assessed on day 5 in Group 2, day 14 in Group 3, and day 21 in Group 4. RESULTS: Angiogenesis was significantly higher in the treatment group than the control group on day 5 and 14 (p = 0.047; 95% CI = 1.23–5.23 and p = 0.032; 95% CI = 0.21–3.28) but not significantly different on day 21 (p = 0.107; 95% CI = −0.43–3.43). The number of fibroblasts in the treatment group was significantly higher on day 5, 14, and 21 (p = 0.004; 0.038; and 0.005; 95% CI = 2.42–17.19; 5.38–16.78; 4.24–15.25). Collagen deposition was not significantly different on day 5 (p = 0.342; 95% CI = −5.65–14.63) but was significantly higher on day 14 and 21 (p = 0.048; 95% CI = 0.11–23.7 and p = 0.002; 95% CI = 10.14–26.57). The epithelialization process occurred earlier in the treatment group than in the control group (p = 0.001). CONCLUSION: Topical administration of resveratrol gel accelerates the epithelialization process, which increases the number of angiogenesis, fibroblasts, and collagen deposition in deep partial thickness burns compared to paraffin gauze.

Effects of resveratrol topical ointment on wound healing of full-thickness cutaneous burns in albino rats

OBJECTIVE

In this study, the effects of resveratrol topical ointment on wound contraction and histopathology of full-thickness cutaneous burn wounds were evaluated.

METHOD

Adult albino rats were grouped into four equal-sized groups of 15 rats each, as follows: Group A-no wound, no treatment (control); Group B-1% silver sulphadiazine; Group C-5% resveratrol, and Group D-wound without treatment (control). A burn wound measuring 23.5mm was created on the skin at the dorsum of all rats in groups B-D after shaving. The percentage of wound contraction was measured using a digital Vernier Caliper on days 1, 3, 5, 7, 10, 14, 16, 18 and 21, post-wounding. From each group, five rats were then euthanised and tissue samples of the skin, liver and kidney were collected in 10% buffered formalin for histopathology.

RESULTS

The percentage of wound contraction was significant (p<0.05) on 7, 14 and 18 days post treatment. Histopathologically, 5% resveratrol topical ointment application resulted in a thicker epidermis with neovascularisation and an increased collagen distribution. Resveratrol topical ointment ameliorated the extent of hepatocellular and nephrotubular injuries following burn-induced hepatocellular and acute kidney injuries.

CONCLUSION

In this study, topical application of 5% resveratrol ointment appeared to enhance burn wound healing by increasing the rate of wound contraction through collagen fibre synthesis, granulation tissue formation and epithelial regeneration.

Nanomedicine-based strategies to improve treatment of cutaneous leishmaniasis

Nanomedicine strategies were first adapted and successfully translated to clinical application for diseases, such as cancer and diabetes. These strategies would no doubt benefit unmet diseases needs as in the case of leishmaniasis. The latter causes skin sores in the cutaneous form and affects internal organs in the visceral form. Treatment of cutaneous leishmaniasis (CL) aims at accelerating wound healing, reducing scarring and cosmetic morbidity, preventing parasite transmission and relapse. Unfortunately, available treatments show only suboptimal effectiveness and none of them were designed specifically for this disease condition. Tissue regeneration using nano-based devices coupled with drug delivery are currently being used in clinic to address diabetic wounds. Thus, in this review, we analyse the current treatment options and attempt to critically analyse the use of nanomedicine-based strategies to address CL wounds in view of achieving scarless wound healing, targeting secondary bacterial infection and lowering drug toxicity.

Comparison of the Effect of Local and Systemic Injection of Resveratrol on Cutaneous Wound Healing in Rats

Purpose. To compare the effect of local and systemic injection of resveratrol (RSV) on open cutaneous wound healing. Materials and Methods. Open cutaneous wounds were created in adult Sprague–Dawley rats. Group 1 (n = 6) was given intraperitoneal RSV (0.5 mg/kg) once daily for 14 days. Group 2 (n = 6) was given local subcutaneous RSV (0.5 mg/kg) on the wound once daily for 14 days. Group 3 (n = 6) did not receive any pharmacologic agent. Biopsy specimens were obtained on postoperative days (PODs) 7, 14, and 21 and were examined histologically. Wound closure time was recorded. All rats were sacrificed on POD 30 for tensile strength analysis. Results. The histological scores for collagen deposition, chronic inflammation, and granulation were higher in the systemic and local RSV treatment groups than in the control group. Neovascularization scores significantly increased on PODs 14 and 21 in the local RSV treatment group compared with those in the systemic RSV and control groups. Systemic and local RSV administrations significantly enhanced wound healing and increased the tensile strength of the skin in rats. Conclusion. Local subcutaneous application of RSV may have a better therapeutic effect than the systemic application of RSV in terms of neovascularization to promote wound healing.