Modification of inflammatory and histopathological factors in an experimental model of loxsocelism in rats with and without hyperbaric oxygen therapy
Authors: Blas Mireille Toledo , Vadillo Antonio Franco , Balcázar Gustavo Guevara , Kovsova Alexander Kormanovski , del Carmen Castillo Hernández María 
Published: April 2020

Introduction

The loxosceles spider, also known as violinist, brown recluse or brown widow, is characterized by presenting a black or brown violin figure on its cephalothorax, also has 6 eyes distributed semicircularly. More than 130 species have been described worldwide.

The poison of the Loxoscelidae family has at least nine components among these: enzymes such as hyaluronidase, deoxyribonuclease, ribonuclease, alkaline phosphatase, lipase and sphingomyelinase D. Sphingomyelinase D are the main cause of the necrosis and hemolysis caused by this poison. The poison action mechanism is not known at all, there are several possible explanations, one of this is the direct action, mediated by the mechanism that leads to hemolysis. Loxosceles poisoning has two important effects from the clinical point of view, its dermonecrotic action and its hemolytic effect. The intensity of this reaction depends on the amount of poison inoculated and the person sensibility to its components. The bite may go unnoticed, but after a few hours the pain appears in the affected area, is like a cigaret burn, followed by general malaise, may be fever, itching, erythema, edema and other symptoms increase in the area as time goes by. The treatment for cutaneous or systemic loxoscelism is generally analgesic, antihistaminic and steroid. Although an antivenom has been developed but the access to this fabotherapeutic is difficult, at some hospitals. The n‐acetylcysteine generates glutathione reducing the damage generated by free radicals caused by sphingomyelinase D, in addition to inhibiting leukocyte migration also reduces inflammation.

Given the lack of specific treatments, the use of hyperbaric oxygen has been considered, there is evidence reporting a significant improvements in all cases. The accumulation of great amounts from oxygen in the affected area can stimulate angiogenesis, migration of fibroblasts and optimization of the immune process, also increase healing factors.

Material and methods

We analyzed the histological changes at the inoculation area of Loxsoceles Reclusa venom, at different stages of evolution in groups, without treatment, with n‐acetilcisteine, with hyperbaric chamber treatment and the both treatment combination. Moreover we compared the modification in the expression of TNFalpha and VEGF by immunohistochemistry and analyze between this groups witch one had better reaction

Results and conclusion

It was found an Improvement in the evolution of the dermonecrotic lesion with hyperbaric oxygen, also increases in the expression of VEGF and decrease of TNF alpha in the same tissues. Histologically, the immune pattern is diminished and the lession area is reduced. Thus we considered that the combinatted therapies offers more beneficial effects on dermonecrosis, applying early and on a time instead just one of the therapies by itself.

Support or Funding Information

Section of postgraduate studies and research and national council of science and technology

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.