The Effect of Platelet-Rich Plasma on the Zone of Stasis and Apoptosis in an Experimental Burn Model

The effect of Tarantula cubensis D6 on zone of stasis in a rat burn model

AIM

Burn injuries are one of the most devastating injuries. Saving the zone of stasis decreases burn size, morbidity, and mortality. Tarantula cubensis (TC) increases epithelization of wounds, and increases wound contraction. In this study, we investigated the effects of TC on the stasis zone.

MATERIALS AND METHODS

36 Wistar albino female rats were divided into 3 groups. Using brass comb burn model, at days 0 and 3, physiological serum solution in group 2, TC injection in group 3and no injection in group 1 was applied. Thermal and normal images were taken on day 10 and rats were sacrificed for histopathological examination.

RESULTS

We found a statistically significant difference between the 1st and 3rd group, 2nd and 3rd group regarding viable wound areas (p < 0.05), temperature difference (body-stasis zone) and mean body temperature (p < 0.05). We found no statistically significant difference between groups regarding neovascularization, inflammatory density, and vital cutaneous appendages. We found a statistically significant difference in epithelial layer thickness between the1st and 3rd groups, 2nd and 3rd groups(p < 0.05).

CONCLUSION

TC increases stasis zone viability macroscopically, increases epithelial layer thickness histopathologically, thus it promotes wound healing in burn wounds. This increase in stasis zone viability was also established with thermal imaging.

Saving zone of stasis in burn wounds by nanoliposomal Mg-ATP

ATP is a crucial molecule for every energy-dependent process in cells. In ischemic tissues, ATP production declines, and it finally results in cell death. One of the most common strategies in burn wound management is saving the zone of ischemia. In the current study, Mg-ATP-containing nanoliposomes were formulated and studied in vitro and in vivo. The particle size of the vesicles was between 50 and 100 nm and the mean zeta potential was -4.05 ± 0.52 mV as evaluated by dynamic light scattering and Zeta sizer instrument, respectively. The encapsulation efficiency of ATP in the nanoliposomes was found to be 9.3%. The morphology and size of nanoliposomes were further studied by transmission electron microscopy. The standard MTT assay revealed no cytotoxicity of the nanoliposomes when tested on the rat fibroblast cells. Forty rats were randomly divided into four groups (N = 10 each). Burn wounds were created by burn comb model on the back of the rats and the zone of stasis in each group was treated every 12 h for 3 days by injecting them with the Mg-ATP-nanoliposomes. Control samples included empty nanoliposomes, unencapsulated Mg-ATP and the Krebs-Henseleit buffer. Laser Doppler flowmetry results revealed that blood perfusion in the zone of ischemia in rats treated with Mg-ATP-nanoliposomes was more than in the other groups (p < 0.05). Histopathology revealed saving zone of stasis by Mg-ATP-nanoliposomes. Findings obtained in this study demonstrated that the formulated Mg-ATP-nanoliposome has the potential to save the stasis zone in burn wounds.

The Effect of Udenafil on Stasis Zone in an Experimental Burn Model

BACKGROUND

Management of the burn injuries is still a problematic issue because the stasis zone may become necrotic. We hypothesized that udenafil, a potent phospodiesterase inhibitor, can be beneficial in burn treatment by enhancing the viability of the stasis zone.

METHODS

Fifteen Wistar rats were randomly divided into 3 groups. Comb burn injury model was conducted bilaterally on the back of rats in each subject. Group 1 received 1 mL/d of saline orally for 7 days. Group 2 received 10 mg/kg per day of udenafil for 7 days. Group 3 received 20 mg/kg per day of udenafil for 7 days. At the end of seventh day, gross morphological and histopathological samples of stasis zone survival were evaluated.

RESULTS

Histopathological examination of groups 2 and 3 revealed that the stasis zone was mostly viable. The mean necrotic area and severity of inflammation was significantly higher in the control group compared with the treatment groups. Significant differences were determined in treatment groups compared with control group in terms of vital stasis zone area and histopathological parameters.

CONCLUSIONS

Udenafil treatment improved tissue survival on zone of stasis in. Future experimental studies should be conducted to develop zone of stasis treatment protocols combining udenafil with potent anti-inflammatory and antioxidant drugs.

Burn Injury: Mechanisms of Keratinocyte Cell Death

Cutaneous burn injury is associated with epidermal loss in the zone of coagulation zone and delayed tissue loss in the zone of stasis. Thus, thermal stress can trigger both necrosis and regulated cell death (RCD) or apoptosis. Experimental in vitro and in vivo work has clearly demonstrated apoptotic events of thermally injured keratinocytes that are accompanied by morphological and biochemical markers of regulated cell death. However, in vivo data for the different pathways of regulated cell death are sparse. In vitro experiments with heat-stressed human keratinocytes have demonstrated death receptor involvement (extrinsic apoptosis), calcium influx, and disruption of mitochondrial membrane potential (intrinsic apoptosis) in regulated cell death. In addition, caspase-independent pathways have been suggested in regulated cell death. Keratinocyte heat stress leads to reduced proliferation, possibly as a result of reduced keratinocyte adhesion (anoikis) or oncogene involvement. Understanding the underlying mechanisms of RCD and the skin’s responses to thermal stress may lead to improved strategies for treating cutaneous burn trauma.

[Not Available]

Platelet rich plasma (PRP) has trophic functions due to a high concentration of growth factors and cytokines. These properties may be of therapeutic interest in the management of burn injuries. In preparation for a clinical study at the Lyon Burn Centre on PRP as an inducer of healing in burns, we carried out a review of the literature looking at the results of the use of this therapy. A review of the literature on the use of PRP for the treatment of burn injuries was performed by querying the PUBMED database using the keywords [platelet rich plasma] AND [burns]. Controlled clinical or pre-clinical studies in English or French were included. Eleven articles were identified, consisting of eight preclinical animal model studies and three clinical studies. These looked at the effects of PRP on the healing of burned areas whether they were grafted or not, on the improvement of neuropathic pain, and on distant skin trophicity. The results of recent preclinical studies show shorter epithelialization times thanks to PRP. In humans, a significant study (201 patients) validates its use in combination with thin skin grafts, and another shows benefits on distant cutaneous trophicity. In conclusion, the use of PRP topically or by injection under the skin has a potential benefit in the management of acute burns. A large-scale series validates its use in clinical practice.