Effects of copaiba oil on dermonecrosis induced by Loxosceles intermedia venom

Abstract

Background: Accidents caused by spiders of the genus Loxosceles constitute an important public health problem in Brazil. The venom of Loxosceles sp induces dermonecrosis at the bite site and systemic disease in severe cases. Traditional medicine based on plant-derived products has been proven to reduce the local effects of envenomation. The present study verified the healing effects of copaiba oil on lesions induced by the venom of L. intermedia. Methods: Cutaneous lesions were induced on the backs of rabbits by intradermal injection of L. intermedia venom. Copaiba oil was applied topically 6 hours after injection; the treatment was repeated for 30 days, after which animal skins were removed and processed for histopathological analysis. Blood samples were also collected before and 24 hours after venom inoculation to measure the hematological parameters. Results: Compared to the control group, the platelet count was reduced significantly in all groups inoculated with venom, accompanied by a decreased number of heterophils in the blood. The minimum necrotic dose (MND) was defined as 2.4 μg/kg. Topical treatment with copaiba oil demonstrated a differentiated healing profile: large skin lesions were observed 10 days after venom inoculation, whereas formation of a thick crust, without scarring was observed 30 days after venom inoculation. Histopathological analysis showed no significant difference after treatment. Nevertheless, the copaiba oil treatment induced a collagen distribution similar to control skin, in marked contrast to the group that received only the spider venom injection. Conclusions: We conclude that copaiba oil may interfere in the healing process and thus propose it as a possible topical treatment for cutaneous lesions induced by L. intermedia venom.

Evaluation of the effects of Loxosceles intermedia’s venom in zebrafish

“…venoms have shown to have variable effects among different animal species. For example, the dermonecrosis provoked by the venom has been established in rabbits [39] , but these effects were not observed in mice injected with the same toxins [40] . Nonetheless, the systemic effects, such as kidney and heart toxicity observed in human loxoscelism, can be studied in mice, as these animals seem to reproduce these injuries when challenged with Loxosceles venoms [33] , [41] .…”

Oxalato De Cálcio

“…O número de ampolas que serão administradas vai variar dependendo da classificação do caso de cada paciente, seguindo a gradação apresentada no quadro 03 a seguir: repercussões sistêmicas e, apesar de não serem comuns, existem relatos de óbitos decorrentes desse veneno ROBINSON et al, 2017). Tais mortes estão associadas principalmente ao acometimento renal (RIBEIRO et al, 2019).…”