The prominent myotoxic effects induced by Bothrops jararacussu crude venom are due, in part, to its polycationic myotoxins, BthTX-I and BthTX-II. Both myotoxins have a phospholipase A2 structure: BthTX-II is an active enzyme Asp-49 PLA2, while BthTX-I is a Lys-49 PLA2 devoid of enzymatic activity. In this study, the effect of low-level laser therapy (LLLT), 685 nm laser at a dose of 4.2 J/cm2 on edema formation, leukocyte influx and myonecrosis caused by BthTX-I and BthTX-II, isolated from Bothrops jararacussu snake venom, was analyzed. BthTX-I and BthTX-II caused a significant edema formation, a prominent leukocyte infiltrate composed predominantly by neutrophils and myonecrosis in envenomed gastrocnemius muscle. LLLT significantly reduced the edema formation, neutrophil accumulation and myonecrosis induced by both myotoxins 24 hours after the injection. LLLT reduced the myonecrosis caused by BthTX-I and BthTX-II, respectively, by 60 and 43%; the edema formation, by 41 and 60.7%; and the leukocyte influx, by 57.5 and 51.6%. In conclusion, LLLT significantly reduced the effect of these snake toxins on the inflammatory response and myonecrosis. These results suggest that LLLT should be considered a potential therapeutic approach for treatment of local effects of Bothrops species venom.

This article reports the anti-inflammatory effect of Blutaparon portulacoides (B. portulacoides), specifically the ethanolic extract of its aerial parts, on the edema formation and leukocyte influx caused by Bothrops jararacussu (B. jararacussu) snake venom and Bothropstoxin-I and II (BthTX-I and II) isolated from this venom as an alternative treatment for Bothrops snakebites. The anti-inflammatory effect of B. portulacoides ethanolic extract was compared with an animal group pretreated with dexamethasone. B. portulacoides ethanolic extract significantly inhibited paw edema induced by B. jararacussu venom and by BthTX-I and II. Also, results demonstrated that the extract caused a reduction of the leukocyte influx induced by BthTX-I. However, the extract was not capable of inhibiting the leukocyte influx induced by the venom and by BthTX-II. In conclusion, these results suggest that the ethanolic extract of this plant possess components able to inhibit or inactivate toxins present in B. jararacussu venom, including its myotoxins, responsible for the edema formation. However, the leukocyte migration caused by the venom and BthTX-II was not inhibited by the plant, probably due to the different mechanisms involved in the edema formation and leukocyte influx. This is the first report of B. portulacoides extract as anti-inflammatory against snake venoms and isolated toxins.