Non-thermal plasma suppresses bacterial colonization on skin wound and promotes wound healing in mice

Abstract

The present study evaluated the effect of non-thermal plasma on skin wound healing in BalB/c mice. Two 6-mm wounds along the both sides of the spine were created on the back of each mouse (n=80) by using a punch biopsy. The mice were assigned randomly into two groups, with 40 animals in each group: a non-thermal plasma group in which the mice were treated with the non-thermal plasma; a control group in which the mice were left to heal naturally. Wound healing was evaluated on postoperative days (POD) 4, 7, 10 and 14 (n=5 per group in each POD) by percentage of wound closure. The mice was euthanized on POD 1, 4, 7, 10, 14, 21, 28 and 35 (n=1 in each POD). The wounds were removed, routinely fixed, paraffin-embedded, sectioned and HE-stained. A modified scoring system was used to evaluate the wounds. The results showed that acute inflammation peaked on POD 4 in non-thermal plasma group, earlier than in control group in which acute inflammation reached a peak on POD 7, and the acute inflammation scores were much lower in non-thermal group than in control group on POD 7 (P<0.05). The amount of granular tissue was greater on POD 4 and 7 in non-thermal group than in control group (P<0.05). The re-epithelialization score and the neovasularization score were increased significantly in non-thermal group when compared with control group on POD 7 and 10 (P<0.05 for all). The count of bacterial colonies was 10(3) CFU/mL on POD 4 and <20 CFU/mL on POD 7, significantly lower than that in control group (10(9) CFU/mL on POD 4 and >10(12) CFU/mL on the POD 7) (P<0.05). It was suggested that the non-thermal plasma facilitates the wound healing by suppressing bacterial colonization.

Non-thermal air plasma promotes the healing of acute skin wounds in rats

“…The wound area was significantly more reduced in the rats treated with NTP than in that of the untreated rats on day 7, and also histological analysis confirmed an enhanced epithelisation and a reduced granulation tissue area after plasma treatment. Respectively, improved wound contraction after the plasma treatment has also been confirmed in other studies using NTP generated from argon, helium or nitrogen1678910111213141516171830.…”

“…While most of the already published studies on wound healing were carried out using argon plasma161718, we applied air plasma, which generates high amounts of reactive nitrogen species, such as nitric oxide (NO), nitrogen dioxide (NO 2 ) and reactive oxygen species such as ozone (O 3 ), superoxide (O 2 − ) and hydroxyl radicals (∙OH). In contrast to air plasma, the composition of the argon plasma significantly differs, and only low amounts of reactive oxygen and nitrogen species are produced, by mixing the argon plasma with the ambient air.…”

“…While several reports demonstrated that argon NTP promotes cell migration and proliferation, NTP generated from air induced cell death, due to the apoptosis or necroptosis related mechanisms2627. Despite the dramatically different effect in vitro , the enhancing plasma effect on wound healing was demonstrated in both argon161718 and air plasma22. Of note, the comparability of these particular studies is disputable, as there is remarkable variability between the plasma generators, plasma dose and voltage value producing the plasma discharges.…”

“…Indeed, a positive effect of NTPs on wound healing without adverse reactions to the surrounding healthy tissue has been reported in animal studies16171819. Furthermore, randomised clinical trials have proven that NTPs can reduce bacteria load as well as promote the healing of chronic wounds, while no side-effects and good treatment tolerability were reported20212223.…”

Dual effects of atmospheric pressure plasma jet on skin wound healing of mice

“…One promising strategy to achieve this goal is the application of cold atmospheric pressure plasma . Yu et al found that cold plasma facilitated wound healing by suppressing bacterial colonization . In vitro human and in vivo animal data from Arndt et al suggested that 2 min of treatment with their MicroPlaSter cold plasma generating device was an effective technique for activating the production of wound healing‐related molecules in dermal fibroblasts and resulted in improved wound healing .…”