Inhibition of Tityus serrulatus venom hyaluronidase affects venom biodistribution

Abstract

Background The hyaluronidase enzyme is generally known as a spreading factor in animal venoms. Although its activity has been demonstrated in several organisms, a deeper knowledge about hyaluronidase and the venom spreading process from the bite/sting site until its elimination from the victim's body is still in need. Herein, we further pursued the goal of demonstrating the effects of inhibition of T . serrulatus venom (TsV) hyaluronidase on venom biodistribution. Methods and principal findings We used technetium-99m radiolabeled Tityus serrulatus venom ( 99m Tc-TsV) to evaluate the venom distribution kinetics in mice. To understand the hyaluronidase’s role in the venom’s biodistribution, 99m Tc-TsV was immunoneutralized with specific anti- T . serrulatus hyaluronidase serum. Venom biodistribution was monitored by scintigraphic images of treated animals and by measuring radioactivity levels in tissues as heart, liver, lungs, spleen, thyroid, and kidneys. In general, results revealed that hyaluronidase inhibition delays venom components distribution, when compared to the non-neutralized 99m Tc-TsV control group. Scintigraphic images showed that the majority of the immunoneutralized venom is retained at the injection site, whereas non-treated venom is quickly biodistributed throughout the animal’s body. At the first 30 min, concentration peaks are observed in the heart, liver, lungs, spleen, and thyroid, which gradually decreases over time. On the other hand, immunoneutralized 99m Tc-TsV takes 240 min to reach high concentrations in the organs. A higher concentration of immunoneutralized 99m Tc-TsV was observed in the kidneys in comparison with the non-treated venom. Further, in situ neutralization of 99m Tc-TsV by anti- T . serrulatus hyaluronidase serum at zero, ten, and 30 min post venom injection showed that late inhibition of hyaluronidase can still affect venom biodistribution. In this assay, immunoneutralized 99m Tc-TsV was accumulated in the bloodstream until 120 or 240 min after TsV injection, depending on anti-hyaluronidase administration time. Altogether, our data show that immunoneutralization of hyaluronidase prevents venom spreading from the injection site. Conclusions By comparing TsV biodistribution in the absence or presence of anti-hyaluronidase serum, the results obtained in the present work show that hyaluronidase has a key role not only in the venom spreading from the inoculation point to the bloodstream, but also in venom biodistribution from the bloodstream to target organs. Our findings demonstrate that hyaluronidase i...

Pioneering Study on Rhopalurus crassicauda Scorpion Venom: Isolation and Characterization of the Major Toxin and Hyaluronidase

“…Unfortunately, we could not explore the hyaluronidase sequence due to the low quantity of pure enzyme recovery. Hyaluronidases facilitate the spreading of toxins into the tissues of the prey/victims, since these enzymes hydrolyze hyaluronan of the interstitial matrix ( 28 , 29 ). P9 is a monomeric hyaluronidase of 54 kDa (reduced) and 45 kDa (non-reduced), as estimated by Tris-Tricine-SDS-PAGE.…”

Amplification of Snake Venom Toxicity by Endogenous Signaling Pathways

“…Hyaluronidases are also important in venom spread and represent a nearly ubiquitous venom component [12,27]. Hyaluronidase activity amplifies the toxicity of crotoxin by enhancing venom distribution.…”

“…Although not present in large quantitites in the venom of any known snakes, hyuronidases apparently act to amplify the toxicity of other venom components by increasing the rate and spread of the injected toxins [12]. The products of proteoglycan hydrolysis produced by hyaluronidases have biological activity as well, with hyaluronan fragments participating in the acute pharmacological effects of envenoming, including the inflammatory response, by upregulating matrix metalloproteases [81].…”

“…This interesting body of work is reviewed by Kemparaju et al [13]. Inhibition of venom hyaluronidase activity with natural or synthetic compounds has been a subject of several recent studies [12,82].…”

Heterologous expression and mutagenesis of recombinant Vespa affinis hyaluronidase protein (rVesA2)

“…Additionally, the proteomic analysis of V. affinis venom performed by Rungsa et al [26] detected venom hyaluronidases, which are major venom proteins. Anti-hyaluronidase serum inhibited or delayed the occurrence of large tissue damage, potentially allowing a more efficient clinical management of the victim [27, 28].…”