Properties of biological and biochemical effects of the Iranian saw-scaled viper (Echis carinatus) venom.

The venom of Echis carinatus is rich in proteins and peptides effective on the hemostatic system. This venom is contains metalloproteinase which convert prothrombin to meizothrombin. The prothrombin activator which leads to the formation of small blood clots inside the blood vessels throughout the body. To understand the mechanism of the effects of Iranian Echis carinatus venom, the effects of E. carinatus on human and Wistar rat plasma, plasma proteins (prothrombin and fibrinogen) and blood coagulation were studied. Proteolytic activity of the crude venom on blood coagulation factors such as prothrombin, partial thromboplastin and fibrinogen times were studied. In the present study the PT test for human plasma was reduced from 13.4 s (±0.59) to 8.6 s (±0.64) when human plasma was treated with crude venom (concentration of venom was 1 mg/ml) and for rat plasma PT was reduced from 14.5 s (±0.47) to 8 s (±0.49). Some possible biological and biochemical effects of IEc crude venom were investigated. The blood coagulation in human and in rat were investigated in vivo and in-vitro. In this paper, we show that the procoagulant action of Echis carinatus venom is due in part to a protein component that activates prothrombin and the procoagulant activity on human and rat plasma was evaluated (Tab. 2, Fig. 2, Ref. 31).

Alginate nanoparticles as a promising adjuvant and vaccine delivery system.

During last decades, diphtheria has remained as a serious disease that still outbreaks and can occur worldwide. Recently, new vaccine delivery systems have been developed by using the biodegradable and biocompatible polymers such as alginate. Alginate nanoparticles as a carrier with adjuvant and prolong release properties that enhance the immunogenicity of vaccines. In this study diphtheria toxoid loaded nanoparticles were prepared by ionic gelation technique and characterized with respect to size, zeta potential, morphology, encapsulation efficiency, release profile, and immunogenicity. Appropriate parameters (calcium chloride and sodium alginate concentration, homogenization rate and homogenization time) redounded to the formation of suitable nanoparticles with a mean diameter of 70±0.5 nm. The loading studies of the nanoparticles resulted in high loading capacities (>90%) and subsequent release studies showed prolong profile. The stability and antigenicity of toxoid were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and ouchterlony test and proved that the encapsulation process did not affect the antigenic integrity and activity. Guinea pigs immunized with the diphtheria toxoid-loaded alginate nanoparticles showed highest humoral immune response than conventional vaccine. It is concluded that, with regard to the desirable properties of nanoparticles and high immunogenicity, alginate nanoparticles could be considered as a new promising vaccine delivery and adjuvant system.

Preparation and in vitro characterization of chitosan nanoparticles containing Mesobuthus eupeus scorpion venom as an antigen delivery system

Hydrophilic nanoparticles have been widely investigated in recent years as delivery systems for therapeutic macromolecules such as antigens. In the present study Mesobuthus eupeus venom-loaded chitosan nanoparticles were prepared via ionic gelation of tripolyphosphate (TPP) and chitosan. The optimum encapsulation efficiency (91.1 percent) and loading capacity (76.3 percent) were obtained by a chitosan concentration of 2 mg/mL, chitosan-to-TPP mass ratio of 2 and M. eupeus venom concentration of 500 µg/mL. The average nanoparticle size at optimum conditions was determined by Zetasizer (Malvern Instruments, UK). The nanoparticle size was about 370 nm (polydispersity index: 0.429) while the zeta potential was positive. Transmission electron microscope (TEM) imaging showed a spherical, smooth and almost homogenous structure for nanoparticles. Fourier transform infrared (FTIR) spectroscopy confirmed tripolyphosphoric groups of TPP linked with ammonium groups of chitosan in the nanoparticles. The in vitro release of nanoparticles showed an initial burst release of approximately 60 percent in the first ten hours, followed by a slow and much reduced additional release for about 60 hours. It is suggested that the chitosan nanoparticles fabricated in our study may provide a suitable alternative to traditional adjuvant systems.(AU)

Clinical and biochemical manifestation produced by scorpion (Hemiscorpius lepturus) venom in experimental animals

Several studies have been published about the clinical and biochemical manifestations produced by the venom of scorpions of the Buthidae family, but very few reports have indicated the manifestations induced by the venom of the Scorpionidae family. Hemiscorpius lepturus is an important scorpion species present in the south and southwestern part of Iran, causing morbidity and mortality in children and adults. For the present study, H. lepturus venom was extracted by electric shock and subcutaneously injected (6.3mg/kg) into a group of six rabbits. Blood collection was carried out before and three hours after venom injection for determination of osmotic fragility and levels of blood sugar, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine phosphokinase (CPK) and alkaline phosphatase (ALP). In vitro studies were also carried out to verify the osmotic fragility of red blood cells (RBCs) exposed to venom concentrations ranging from 0-90µg/2ml blood. Results showed the extreme effect of this venom on the lysis of RBCs both in vitro and in vivo. Venom injection caused significant (p>0.001) increase in ALT, AST, LDH and blood sugar levels. There was also an increase in CPK, and ALP levels after venom injection; however, it was not statistically significant. All animals died four hours after having received the venom. The current study revealed that the neurological effect of H. lepturus venom is similar to that of scorpions of the Buthidae family. However, they differ in RBCs lysis, which was highly significant when induced by H. lepturus venom, probably due to the presence of a type of phospholipase in this venom. Further studies are needed to provide a clearer view of the mechanism of action of H. lepturus venom.(AU)