Green synthesis of gold nanoparticles in an animal model of chronic wound induced with Resiquimod.

Cost-effective strategies for the treatment of chronic wounds must be developed. The green synthesis of gold nanoparticles (GNPs) it is possible to guarantee a lower toxicity in biological tissues and greater safety of applicability, in addition to adding the effects of nanoparticles (NPs) to those of extracts. The objective of this study was to evaluate the effects of treatment with biosynthesized GNPs in a chronic wound model. Wistar rats were distributed into 7 groups: Acute Wound (AW); Chronic wound (CW); CW + GNPs-Açaí; CW + GNPs-DB; CW + AV-GNPs; CW + SafGel®; CW + 660 nm laser. The chronic injury model was induced with topically applied Resiquimod for 6 days. Treatments were then initated on the fourteenth day after the last application of Resiquimod and carried out daily for ten days. The proposed therapies with GNPs were able to significantly reduce the inflammatory score and increase the rate of wound contraction. In histology, there was a reduction in the inflammatory infiltrate and increased gene expression of fibronectin and type III collagen, mainly in the CW + AV-GNPs group. The therapies were able to reduce pro-inflammatory cytokines, increase anti-inflammatory cytokines, and reduce oxidative stress. The results demonstrated that the effects of GNPs appear to complement those of the extracts, thereby enhancing the tissue repair process.

Bacterial nanocellulose/calcium alginate hydrogel for the treatment of burns.

PURPOSE: Bacterial cellulose (BC) has shown high capacity for the treatment of wounds and burns, providing a moisty environment. Calcium alginate can be associated with BC to create gels that aid in wound debridement and contribute to appropriate wound healing. This study is aimed at characterizing and evaluating the use of bacterial cellulose/alginate gel in skin burns in rats. METHODS: Cellulose and cellulose/alginate gels were compared regarding the capacity of liquid absorption, moisture, viscosity, and potential cytotoxicity. The 2nd degree burns were produced using an aluminum metal plate (2.0cm) at 120ºC for 20s on the back of rats. The animals were divided into non-treated, CMC(Carboxymethylcellulose), Cellulose(CMC with bacterial cellulose), and Cellulose/alginate(CMC with bacterial cellulose and alginate). The animals received topical treatment 3 times/week. Biochemical (MPO, NAG and oxidative stress), histomorphometry and immunohistochemical assays (IL-1ß IL-10 and VEGF) were conducted on the 14th, 21st, 28th, and 35th days. RESULTS: Cellulose/Alginate gel showed higher absorption capacity and viscosity compared to Cellulose gel, with no cytotoxic effects. Cellulose/alginate presented lower MPO values, a higher percentage of IL-10, with greater and balanced oxidative stress profile. CONCLUSIONS: The use of cellulose/alginate gel reduced neutrophils and macrophage activation and showed greater anti-inflammatory response, which can contribute to healing chronic wounds and burns.

Bacterial nanocellulose/calcium alginate hydrogel for the treatment of burns

Purpose: Bacterial cellulose (BC) has shown high capacity for the treatment of wounds and burns, providing a moisty environment. Calcium alginate can be associated with BC to create gels that aid in wound debridement and contribute to appropriate wound healing. This study is aimed at characterizing and evaluating the use of bacterial cellulose/alginate gel in skin burns in rats. Methods: Cellulose and cellulose/alginate gels were compared regarding the capacity of liquid absorption, moisture, viscosity, and potential cytotoxicity. The 2nd degree burns were produced using an aluminum metal plate (2.0cm) at 120ºC for 20s on the back of rats. The animals were divided into non-treated, CMC(Carboxymethylcellulose), Cellulose(CMC with bacterial cellulose), and Cellulose/alginate(CMC with bacterial cellulose and alginate). The animals received topical treatment 3 times/week. Biochemical (MPO, NAG and oxidative stress), histomorphometry and immunohistochemical assays (IL-1ß IL-10 and VEGF) were conducted on the 14th, 21st, 28th, and 35th days. Results: Cellulose/Alginate gel showed higher absorption capacity and viscosity compared to Cellulose gel, with no cytotoxic effects. Cellulose/alginate presented lower MPO values, a higher percentage of IL-10, with greater and balanced oxidative stress profile. Conclusions: The use of cellulose/alginate gel reduced neutrophils and macrophage activation and showed greater anti-inflammatory response, which can contribute to healing chronic wounds and burns.

Effects of phonophoresis with ibuprofen associated with gold nanoparticles in animal model of traumatic muscle injury.

The repair process consists of molecular and cellular events that can be accelerated by specific therapies. Considering this, the objective of this study was to evaluate the effects of ibuprofen phonophoresis associated with gold nanoparticles in the animal model of traumatic muscle injury. Was used 80 male wistar rats divided into eight groups: Sham; Muscle injury (MI); MI + therapeutic pulsed ultrasound (TPU); MI + Ibuprofen (IBU); MI + GNPs; MI + TPU+ IBU; MI + TPU + GNPs and MI + TPU + IBU + GNPs. The lesion in the gastrocnemius was performed by a single direct trauma impact on the injured press. The animals were treated with pulsed ultrasound and the gel with gold nanoparticles and/or ibuprofen. The treatment was applied daily for 5 days and the first session was 12 h after the muscle injury. The gastrocnemius muscle was surgically removed for analyzes biochemical, molecular and histological. In the analyzes only the MI + TPU + IBU + GNPs group showed a reduction in TNF-a and IL-1 levels, with a concomitant increase in the levels of anti-inflammatory cytokines. In the analysis of oxidative stress, only the MI + TPU + IBU + GNPs group presented a reversal of the condition when compared to the MI group. In the histological analysis, the MI group presented a large cell infiltrate and a centralized nucleus and only the MI + TPU + IBU + GNPs group showed a structural improvement, also in the pain results the MI + TPU + IBU + GNPs showed a significant difference in comparison to the MI group (p<0.01). We believe that the effects of phonophoresis with anti-inflammatory drugs associated with gold nanoparticles may potentiate the reduction of the inflammatory response and regulate the cellular redox state.