Effect of Subcutaneous Topical Ozone Therapy on Second-Degree Burn Wounds in Rats: An Experimental Study

The impact of subdermal adipose derived stem cell injections and early excision on systemic oxidative stress and wound healing in rats with severe scald burns

AIM

This study aims to develop an experimental treatment model effective against oxidative stress in the acute period of severe burns and to analyze the mechanisms of healing large wound defects.

METHODS

Five rats, including 2 females and 3 males, were used as donors to obtain adipose-derived stem cells (ADSC) from the inguinal fat pad. The stem cells were labeled with green fluorescent protein. The study included four groups of 17 rats, each with grade 3 scalding burns on 30 % of their body surface, and a control group of 10 rats with an equal number of males and females. After early excision, 106 ADSC-derived stem cells were administered subdermally to the burned wound and autografted to the stem cell group (n = 17). The early excision group (n = 17) received early excision and autograft, with 2 ml of normal saline injected subdermally into the burn wound edge. The PLM group (n = 17) was treated with a polylactic membrane (PLM) dressing after the burn. No treatment was given to the burn group (n = 17). Ten rats from all groups were sacrificed on the 4th day post-burn for oxidative stress evaluation. The control group (n = 10) was sacrificed on day 4. Blood and tissue samples were collected post-sacrifice. Oxidative stress and inflammation in the blood, as well as cell damage in the skin, liver, kidneys, and lungs, were investigated histopathologically and biochemically on the 4th day post-burn. On the 70th day after burn, wound healing was examined macroscopically and histopathologically.

RESULTS

On the 4th day, oxidative stress results showed that the levels of Total Oxidative Capacity (TOC) in the blood were lowest in the stem cell (7.4 [6-8.8]), control (6.7 [5.9-7.6]), and early excision (7.5 [6.6-8.5]) groups, with no significant difference between them. The burn group (14.7 [12.5-16.9]) had the highest TOC levels. The PLM group (9.7 [8.6-10.7]) had lower TOC levels than the burn group but higher levels than the other groups. Histopathological examination on the 4th day revealed low liver caspase-3 immunoreactivity in the stem cell and early excision groups among the burn groups. Caspase-3 immunoreactivity levels were as follows: stem cell group (20 [10-30]), early excision group (25 [15-50]), PLM group (70 [50-100]), control group (0), and burn group (80 [60-120]). Other oxidative stress and end-organ damage outcomes were consistent with these results. All rats in the stem cell group had burn wounds that healed completely by the 70th day. Examination of the skin and its appendages from the stem cell group with an immunofluorescence microscope demonstrated green coloration, indicating incorporation of stem cells.

CONCLUSION

Stem cells may have the potential to form new skin and its appendages, providing better healing for large skin defects. Early excision treatment, by removing local necrotic tissues after extensive and deep burns, can prevent end-organ damage due to systemic oxidative stress and inflammation. We also believe that when these two treatments are used together, they can achieve the best results.

Ninety Sixth-Hour Impact of Scalding Burns on End Organ Damage, Systemic Oxidative Stress, and Wound Healing in Rats Treated With Three Different Types of Dressings

In this study, we investigated the effects of 3 different burn dressing treatments, including experimental, silver, and modern dressing materials, on systemic oxidative stress in rats with severe scald burns within the first 96 h. The rats were divided into five groups: a burn group (n = 10), a polylactic membrane group (n = 10), a silver sulfadiazine group (n = 10), a curcumin group (n = 10), and a control group (n = 10), consisting of equal numbers of female and male rats. In the first 4 groups, 30% of the rats' total body surface area was scalded at 95°C. The burn group was not treated. Each group was treated with group-name dressing material. The control group was neither treated nor burned. The rats were sacrificed, and blood and tissue samples were obtained at the 96th hour when severe effects of oxidative stress developed postburns. Systemic inflammatory biomarkers and oxidative stress parameters were examined. In addition, apoptosis and organ damage in liver, kidney, lung, and skin tissues were evaluated biochemically and histopathologically. When the parameters were statistically analyzed, we found that the systemic levels of oxidative stress and inflammatory damage to liver, kidney, and lung tissues were lower in the 3 treated groups than in the burn group. We believe that the dressing material's efficacy in the treatment of severe burns may be dependent on its ability to combat oxidative stress and inflammation.

Effect of Ozone Therapy on Epidural Fibrosis in Rats

OBJECTIVE

To demonstrate the effect of medical ozone therapy on the development of epidural fibrosis.

METHODS

A total of 25 Sprague-Dawley male rats were randomly divided into 3 groups: a control group (L3-L4 laminectomy only), a systemic ozone therapy (SOT) group (L3-L4 laminectomy only + intraperitoneal 15 mL [30 μg/mL] ozone), and a local ozone therapy (LOT) group (L3-L4 laminectomy only + subcutaneous 15 mL [30 μg/mL] ozone). Ozone therapy was administered 4 times on a 3-day interval during the wound-healing process, with the first dose immediately administered after surgery. The effects of ozone therapy on vascular endothelial growth factor, inflammation, and epidural fibrosis between groups were evaluated.

RESULTS

Staining with vascular endothelial growth factor was significantly less in the group that received SOT compared with the control group (P = 0.021). When the groups were compared in terms of inflammation, it was found that inflammation was less common in the SOT and LOT groups compared with the control group (SOT vs. control: P = 0.004 and LOT vs. control: P = 0.024), whereas inflammation was found to be significantly less in the SOT group compared with the LOT group (P = 0.008). In the histopathologic evaluation of epidural fibrosis, there was no significant difference between the SOT and LOT groups but less epidural fibrosis was observed in both groups compared to the control group (LOT vs. control: P = 0.037; SOT vs. control: P = 0.018).

CONCLUSIONS

Medical ozone therapy may be an alternative method that can be used effectively and safely in the prevention of epidural fibrosis after laminectomy.

Estimation of Effectiveness of Local Reactive Oxygen Species for Stimulation of Regenerative Processes in Experimental Burn Wound

The aim of this work was the comparative estimation of the efficiency of different variants of local ozone therapy in experimental burn wound. We conducted the experiments on 45 white Wistar rats being randomized for three groups. Every rat got contact thermal trauma (III degree; 20 bsp) of dorsal body surface on the area 20%. Rats of the first group received a Levomecol treatment of wound, animals of the second group were locally treated by ozonized oil, and the third group rats received a combination of ozone and oxygen gas mixture intracutaneously, and the wounds were treated with Levomecol locally. The character and particularities of post-traumatic regeneration were studied by histological investigation. Local treatment with reactive oxygen species at an early period after burning is revealed to lead to more pronounced manifestation of reparative processes in burn wounds (production of granulation tissue, epidermis regeneration) than when applying Levomecolointment, and that is accompanied by more pronounced initial manifestation of scab rejection. Applying reactive oxygen species in ointment compositions at these stages of treatment with the conjuncture of infected wounds does not contribute marked initiation of reparative processes and can even force the inflammation processes.

Low Ozone Concentrations Differentially Affect the Structural and Functional Features of Non-Activated and Activated Fibroblasts In Vitro

Oxygen-ozone (O2-O3) therapy is increasingly applied as a complementary/adjuvant treatment for several diseases; however, the biological mechanisms accounting for the efficacy of low O3 concentrations need further investigations to understand the possibly multiple effects on the different cell types. In this work, we focused our attention on fibroblasts as ubiquitous connective cells playing roles in the body architecture, in the homeostasis of tissue-resident cells, and in many physiological and pathological processes. Using an established human fibroblast cell line as an in vitro model, we adopted a multimodal approach to explore a panel of cell structural and functional features, combining light and electron microscopy, Western blot analysis, real-time quantitative polymerase chain reaction, and multiplex assays for cytokines. The administration of O2-O3 gas mixtures induced multiple effects on fibroblasts, depending on their activation state: in non-activated fibroblasts, O3 stimulated proliferation, formation of cell surface protrusions, antioxidant response, and IL-6 and TGF-β1 secretion, while in LPS-activated fibroblasts, O3 stimulated only antioxidant response and cytokines secretion. Therefore, the low O3 concentrations used in this study induced activation-like responses in non-activated fibroblasts, whereas in already activated fibroblasts, the cell protective capability was potentiated.