Evaluation of the healing potential of nanoemulsion containing green propolis extract in the treatment of wounds in hyperglycemic rats infected with methicillin-resistant Staphylococcus aureus

• Grant number: 21/10516-0
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): January 01, 2022
• Effective date (End): December 31, 2022
• Field of knowledge: Biological Sciences - Morphology - Histology
• Principal researcher: Claudia Helena Pellizzon
• Grantee: Marcos Vital de Sa Ferreira
• Home Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated research grant: 17/04138-8 - Attainment of chemical, analytical, biological, pharmacological and technological studies to fill the gaps on the development of Brazilian propolis sector, AP.TEM

Abstract

Diabetes Mellitus is a chronic disease that affects millions of people and causes serious metabolic changes in the body of patients. Difficulty in wound healing is one of its main complications, which can be explained by the continuous inflammatory process and high rate of oxidative stress. This condition, associated with infection by the bacteria Staphylococcus aureus resistant to methicillin (MRSA), causes a worsening in the patient that results in a high number of limb amputations. Therapy with the use of antibiotics is costly for low-income people, and the search for new therapeutic treatments, mainly based on natural products of plant origin, has become a potential alternative to treat these wounds. Green propolis, originating from field rosemary (Baccharis dracunculifolia), stands out for being composed of 16 phenolic compounds with the majority presence of phenylpropanoids, such as Artepelin C, which has been observed due to its anti-inflammatory, antioxidant and antitumor properties. However, its direct use in topical formulations may be restricted due to its unfavorable properties. Thus, the use of nanotechnology aims to correct these limitations and enable the encapsulation of plant extracts and/or isolated substances. In this project, the healing action of nanoemulsions containing green propolis extract rich in Artepelin C will be investigated in experimental models in vivo. For this, male Wistar rats will be randomly divided into seven groups (n=7). The experimental induction of diabetes will be by a single intraperitoneal application of streptozotocin at a dose of 55 mg/kg. After confirming the animals' diabetic status, anesthesia will be carried out and, subsequently, wounds will be made in the dorsal region with the aid of a punch measuring 2 cm in diameter. Then, the bacterial inoculum (S. aureus (USA 300) resistant to meicillin) will be applied to the surgical wound of the animals, and 24 hours after the inoculation, the first swab will be collected to prove the contamination of the wound. Lesions will be treated twice a day for 14 days. The area of the wounds will be measured daily to check macroscopic reduction and the clinical appearance of the lesions. After euthanasia, the wounds will be destined for histopathological analysis. This work is an integral part of the thematic project approved by FAPESP (FAPESP Process: 2017/04138-8): "Conducting chemical, analytical, biological, pharmacological and technological studies to fill gaps in the development of the Brazilian propolis sector". (AU)