Antimicrobial Profile of Selected Snake Venoms and Their Associated Enzymatic Activities.

Aims: To investigate the antiviral and antibacterial profile of several crude snake venoms and to assess some of their enzymatic activities. Methodology: The antiviral activities of Naja haje, Bitis arietans, Naja nigricollis and Echis carinatus snake venoms were investigated against Herpes simplex virus type1, Rift valley fever virus and Vesicular stomatitis virus using the end point of cytopathic effect method. Antibacterial activities of Bitis arietans, Cerastes cerastes, Echis carinatus, Vipera lebetina, Naja naja, Pseudechis australis, Naja nigricollis and Naja haje venoms were examined against Staphylococcus aureus, Escherichia coli, Salmonella typhimurium and Pseudomonas aeruginosa using disc diffusion method. Microdilution method was used to determine the venom's minimum inhibitory concentration. L-amino acid oxidase and phospholipase A2 activities of crude venoms were evaluated using enzymatic assays. Results: Naja nigricollis, Bitis arietans and Echis carinatus snake venoms exhibited significant antiviral activities against all test viruses, except for N. haje treated cells. The mean depletion of viral infectivity titer of venom pretreated cells was higher than its depletion post viral infection for all three venoms showing antiviral activities. Naja nigricollis exhibited the highest antiviral activity against test viruses and recorded a mean depletion of viral infectivity titer in venom pretreated cells of 3.8 log (10) / ml , 3.2 log (10) / ml and 2.5 log (10) / ml for HSV-1, RVFV and VSV, respectively. Pseudechis australis, followed by Naja naja and Naja nigricollis venoms, showed the highest inhibitory activity against test bacteria with inhibition zones ranging from 11-17 mm, 8-14 mm and 8-13 mm, respectively. Minimum inhibitory concentrations of test venoms against different bacterial strains ranged from 156 μg / ml to 1.25 mg / ml. Maximum L- amino oxidase activity was detected in Naja naja, Cerastes cerastes and Pseudechis australis. The highest Phospholipase A2 activity was identified in Bitis arietans, Pseudechis australis, Naja naja and Naja nigricollis. Conclusion: It can be concluded that snake venoms or their bioactive derivatives can be promising therapeutic agents against some microbial infections. Further investigations will be carried out for purification and more characterization of the biologically active components in snake venoms.

Detection of an early marker of atherosclerosis among non-insulin dependent-diabetic patients

An early marker of subclinical arteriosclerosis, the increased intimal-medial thickness [IMT] of the common carotid artery was measured by B-mode ultrasound in twenty non-diabetic and thirty non- insulin- dependent diabetic patients [ten newly diagnosed and twenty well established diabetics]. This marker was compared in non- diabetic and diabetic subjects to evaluate its correlation with some cardiovascular risk factors, and duration of diabetes. In addition, body mass index [BMI], waist to hip ratio [WHR], blood pressure, glycosylated hemoglobin [HbAic] and fasting concentrations of plasma glucose, serum lipids and serum insulin were measured in all subjects. In conclusion, diabetes is characterized by a greater thickness of the carotid artery, which lead to increased risk of arteriosclerosis. Also, central adiposity is considered as a predictor of IMT in non- diabetic individuals