Experimental Production and Efficacy Testing of Mono-specific Antibodies against the Venom of Carpet viper (Echis ocellatus) from Savannah Nigeria.

Echis ocellatus is one of the commonest snakes responsible for envenomation in Nigeria. Antivenom is the only effective treatment, but the country suffers from a limited supply of effective antivenom. This study therefore aimed to explore the feasibility of effective, mono-specific antibodies production through immunization in rabbits using the venom of Echis ocellatus from Nigeria. The World Health Organization guide on antivenom production was employed in the immunization and the resultant antibodies were purified using protein A agarose column chromatography. Antibody titer reached a high plateau by 2-month immunization, and SDS PAGE of the sera suggests the presence of intact immunoglobulins accompanied with the heavy (50 kDa) and light (25 kDa) chains. The venom has an intravenous LD50 of 0.35 mg/kg in mice, and the venom lethality at a challenge dose of 2 LD50 was effectively neutralized by the antibodies with a potency value of 0.83 mg venom per g antibodies. The antibodies also neutralized the procoagulant activity of the venom with an effective dose (ED) of 13±0.66 ul, supporting its use for hemotoxic envenomation. The study establishes the feasibility of developing effective, mono-specific antibodies against the Nigerian Carpet viper.

Kinetics and computational study of butyrylcholinesterase inhibition by methylrosmarinate: relevance to Alzheimer's disease treatment.

Butyrylcholinesterase (BChE) performs a significant function in Alzheimer's disease progression. Experimental studies have shown that the function of BChE in the attenuation of cholinergic neurotransmission is essentially altered in brains of advanced AD patients. Here, using the complimentary methods of enzyme kinetic studies, molecular modeling and protein-ligand interaction profiling, we sought to reveal the mechanistic and structural features of BChE-methyrosmarinate interactions. Molecular docking simulations revealed that methylrosmarinate dwelled well in the active centre of BChE, where it got involved in stabilizing non-covalent associations with myriad subsites. Enzyme kinetic experiments showed that the V m and K s values were 156.20 ± 3.11 U mg-1 protein and 0.13 ± 0.01 µM, respectively. The inhibition studies showed that methylrosmarinate apparently inhibited BChE in a linear mixed manner, with an IC 50 value of 10.31 µM and a K i value of 3.73 ± 1.52 µM. Taken together, the extremely reduced K i value and the increased number of BChE-methylrosmarinate interactions presuppose that methylrosmarinate is a good inhibitor of BChE, despite the fact that the mechanism for the effect of BChE inhibition on several pathological conditions in vivo remains unexplored.