Effects of Purified Tick Saliva Toxins on Various Bio-Molecules in Blood Serum, Liver and Muscles of Albino Mice

Abstract

In the present study, salivary toxins from Rhipicephalus microplus were isolated and purified on a Sepharose CL 6B 200 gel column at a constant flow rate with regular fractions of 5 mL/min. Pooled fractions were lyophilized and LD₅₀ was then determined in albino mice. The LD₅₀ value of the protein toxin of Rhipicephalus microplus was found 36.11 mg/kg body weight of albino mice. To determine physiological effects, a sub-lethal dose of Rhipicephalus microplus toxin and 40-80% 24 h LD₅₀ of salivary toxin were injected into albino mice. In different biological assays, total serum protein, free amino acids, uric acid, cholesterol, pyruvic acid, total serum lipids and glucose levels were determined at different stages. In addition, the effects of toxins purified from tick saliva were observed on the rectus abdomens, gastrocnemius, muscles, atria and ventricles of albino rats and muscle glycogen. A significant increase in bimolecular activity was observed in the serum, liver and muscle of albino mice. The group injected with the saliva toxin showed an increase in serum protein content of 79.70% while the content of free amino acids, uric acid, cholesterol, pyruvic acid, total lipids and glucose all increased correspondingly. Toxins from tick saliva broke down glycogen stores in the liver, abdominal muscles, stomach muscles, atria and ventricles of albino mice. Toxins in tick saliva significantly reduced glycogen concentrations (67-82%) in the serum, liver, muscle and ventricles of albino mice. These effects were due to the presence of low molecular weight proteins that act on the membrane and interfere with muscle cell function in albino mice. These proteins could be used for drug development and target molecules for the generation of transmission-blocking vaccines or anti-tick vaccines.