Iontophoresis with gold nanoparticles improves mitochondrial activity and oxidative stress markers of burn wounds

The aim of this study was to analyse the effects of microcurrent and gold nanoparticles on oxidative stress parameters and the mitochondrial respiratory chain in the healing of skin wounds. Thirty 60-day old male Wistar rats (250-300 g) were divided into five groups (N=6): Control; Burn wounds; Microcurrent (MIC); Gold nanoparticle gel (GNP gel) and Microcurrent+Gold nanoparticle gel (MIC+GNP gel). The microcurrent treatment was applied for five consecutive days at a dose of 300 μA. The results demonstrate a significant decrease in the activity of complexes I, II-III and IV in the Burn Wounds group compared to the control, and the MIC+GNP gel group was able to reverse this inhibition in complexes I, III and IV. Furthermore, a significant reduction in oxidative damage parameters and a significant increase in the levels of antioxidant defence enzymes were induced in the MIC+GNP gel group compared to the Burn Wounds group. The data strongly indicate that the group receiving treatment with MIC+GNP gel had improved mitochondrial functioning and oxidative stress parameters, which contributed to tissue repair.

Gold nanoparticles and diclofenac diethylammonium administered by iontophoresis reduce inflammatory cytokines expression in Achilles tendinitis

Introduction

Tendinitis affects a substantial number of people in several occupations involving repetitive work or direct trauma. Iontophoresis is a therapeutic alternative used in the treatment of injury during the inflammatory phase. In recent years, gold nanoparticles (GNP) have been studied due to their therapeutic anti-inflammatory capacity and as an alternative to the transport of several proteins.

Purpose

This study evaluates the therapeutic effects of iontophoresis using GNPs and diclofenac diethylammonium on inflammatory parameters in rats challenged with traumatic tendinitis.

Methods

Wistar rats were divided in three treatment groups (n = 15): (1) iontophoresis + diclofenac diethylammonium; (2) iontophoresis + GNP; and (3) iontophoresis + diclofenac diethylammonium + GNP. External control was formed by challenged tendons without treatment (n = 15). Iontophoresis was administered using 0.3 mA direct current on 1.5 cm² electrodes.

Results

The levels of both inflammatory cytokines were significantly higher in untreated challenged rats, when compared with the control (5.398 ± 234 for interleukin 1 beta and 6.411 ± 432 for tumor necrosis factor alpha), which confirms the occurrence of an inflammatory stage in injury (P < 0.05). A significant decrease was observed in expression of cytokines interleukin 1 beta in the three treatment groups, in comparison with untreated challenged tendons, although, in the group treated with diclofenac and GNP, results were similar to the control (1.732 ± 239) (P < 0.05). Concerning tumor necrosis factor alpha, only the group treated with the association diclofenac and GNPs presented decreased levels, compared with the control (3.221 ± 369) (P < 0.05).

Conclusion

The results show the efficacy of drug administration using direct current to treat tendinitis in an animal model, and the potential anti-inflammatory, carrier, and enhancing effects of GNPs in iontophoresis.