Photobiomodulation of local alterations induced by BthTX-I, a phospholipase A2 myotoxin from Bothrops jararacussu snake venom: In vivo and in vitro evaluation.

This report describes the effect of photobiomodulation (PBM) on edema formation, leukocyte influx, prostaglandin E2 (PGE2) biosynthesis and cytotoxicity caused by bothropstoxin-I (BthTX-I), a phospholipase A2 (PLA2) homologue isolated from Bothrops jararacussu snake venom. Swiss mice or C2C12 cells were irradiated with low-level laser (LLL) at 685nm wavelength, an energy density of 4.6J/cm2 and an irradiation time of 13s. To evaluate the effect on edema formation and leukocyte influx, LLL was applied to the site of inoculation 30min and 3h post-injection. C2C12 cells were exposed to BthTX-I and immediately irradiated. PBM significantly reduced paw edema formation, peritoneal leukocyte influx and PGE2 synthesis, but increased the viability of C2C12 muscle cells after BthTX-I incubation. These findings demonstrate that PBM attenuated the inflammatory events induced by BthTX-I. The attenuation of PGE2 synthesis could be an important factor in the reduced inflammatory response caused by laser irradiation. The ability of LLL irradiation to protect muscle cells against the deleterious effects of BthTX-I may indicate preservation of the plasma membrane.

Photobiostimulation reduces edema formation induced in mice by Lys-49 phospholipases A2 isolated from Bothrops moojeni venom.

The prominent local myotoxic effects induced by Bothrops snake venom are due, in part, to myotoxins. This effect is not neutralized by antivenom, which is the main therapy for victims of snakebite. Two basic myotoxins named MjTX-I and MjTX-II were isolated from Bothrops moojeni venom. Both myotoxins have a Lys-49 phospholipase A2 structure devoid of enzymatic activity, but are highly myonecrotic and edema-inducing. In this study, we analyzed the effect of a low-level laser (LLL) at 685 nm, an energy density of 2.2 J cm(-2), and the irradiation time of 15 s, and a light emitting diode (LED) at 635 or 945 nm at energy densities of 4 and 3.8 J cm(-2), and irradiation times of 41 and 38 s, respectively, applied 30 min and 3 h after edema formation in mice caused by MjTX-I or MjTX-II. MjTX-I or MjTX-II caused a significant edema formation in envenomed paws. LLL and LED irradiation significantly reduced the edema formation by both myotoxins from 1 up to 6 hours after the injection. Both LLL and LEDs were similar in reducing the edema formation induced by myotoxins. The combined photobiostimulation with antivenom had the same effect in reducing edema as treatment with the LLL or LEDs alone. In conclusion, the results of this study indicate that photobiostimulation could be used in association with antivenom therapy for treatment of local effects of Bothrops species venom.