Endogenous phospholipase A2 inhibitors in snakes: a brief overview

The blood plasma of numerous snake species naturally comprises endogenous phospholipase A2 inhibitors, which primarily neutralize toxic phospholipases A2 that may eventually reach their circulation. This inhibitor type is generally known as snake blood phospholipase A2 inhibitors (sbPLIs). Most, if not all sbPLIs are oligomeric glycosylated proteins, although the carbohydrate moiety may not be essential for PLA2 inhibition in every case. The presently known sbPLIs belong to one of three structural classes - namely sbαPLI, sbβPLI or sbγPLI - depending on the presence of characteristic C-type lectin-like domains, leucine-rich repeats or three-finger motifs, respectively. Currently, the most numerous inhibitors described in the literature are sbαPLIs and sbγPLIs, whereas sbβPLIs are rare. When the target PLA2 is a Lys49 homolog or an Asp49 myotoxin, the sbPLI is denominated a myotoxin inhibitor protein (MIP). In this brief overview, the most relevant data on sbPLIs will be presented. Representative examples of sbαPLIs and sbγPLIs from two Old World - Gloydius brevicaudus and Malayopython reticulatus - and two New World - Bothrops alternatus and Crotalus durissus terrificus - snake species will be emphasized.(AU)

Endogenous phospholipase A2 inhibitors in snakes: a brief overview

The blood plasma of numerous snake species naturally comprises endogenous phospholipase A2 inhibitors, which primarily neutralize toxic phospholipases A2 that may eventually reach their circulation. This inhibitor type is generally known as snake blood phospholipase A2 inhibitors (sbPLIs). Most, if not all sbPLIs are oligomeric glycosylated proteins, although the carbohydrate moiety may not be essential for PLA2 inhibition in every case. The presently known sbPLIs belong to one of three structural classes namely sbPLI, sbPLI or sbPLI depending on the presence of characteristic C-type lectin-like domains, leucine-rich repeats or three-finger motifs, respectively. Currently, the most numerous inhibitors described in the literature are sbPLIs and sbPLIs, whereas sbPLIs are rare. When the target PLA2 is a Lys49 homolog or an Asp49 myotoxin, the sbPLI is denominated a myotoxin inhibitor protein (MIP). In this brief overview, the most relevant data on sbPLIs will be presented. Representative examples of sbPLIs and sbPLIs from two Old World Gloydius brevicaudus and Malayopython reticulatus and two New World Bothrops alternatus and Crotalus durissus terrificus snake species will be emphasized.

Notes of cases of aggression and ophiophagy by Bothops jararacussu (Lacerda 1884) in captivity / Nota de casos de agresión y ofiofagia por Bothrops jararacussu (Lacerda 1884) en cautividad

Bothrops jararacussu is one of the most venomous snakes of medical importance in South America, mainly due to the toxicity of their venom and the large amount of that which can be injected in a single bite. The venom of this snake is required for the production, process and control of the therapeutic antivenoms used to treat Bothrops envenomation, so it is one of the Bothrops species common in Serpentariums located in Argentina and Brazil dedicated to the production of antivenoms. We reported two cases of ophiophagy due captive adult B. jararacussu females on Bothrops and Philodryas snakes and the aggression of specimens of this species is also described. Despite well known resistance to homologous venom of Bothrops species, the bite of this specie on other snakes of the same species and also other Bothrops snakes, produce serious injuries. These observations are important for professionals whom must maintain in captivity these species of snakes by educational or venom production purposes.

Bothrops jararacussu es una de las serpientes venenosas de mayor importancia médica en Sudamérica, tanto por la toxicidad de su veneno como por la cantidad de veneno que puede inyectar. Su veneno es necesario para el proceso de producción y control del antiveneno terapéutico que se usa para tratar el envenenamiento por su mordedura, por eso es una de las especies de Bothrops comunes en los serpentarios de Argentina y Brasil dedicados a la producción de antivenenos. Por otro lado, dada la peligrosidad de su mordedura, estas serpientes suelen encontrarse en diferentes serpentarios educativos en los mismos países. En este trabajo describimos la ofiofagia de ejemplares hembras adultas de esta especie sobre ejemplares de Bothrops y Philodryas. También es descripta la agresión de ejemplares de esta especie a otros ejemplares conespecíficos y de otras especies de Bothrops. A pesar de la conocida resistencia a los venenos homólogos que poseen los ofidios, la inoculación del veneno de esta especie a otros ejemplares de la misma especie como a otras Bothrops produce lesiones de consideración. Estas observaciones son de importancia para quienes deban mantener ejemplares de esta especie en cautividad por motivos educativos o de producción de veneno.

NRAMP1 gene polymorphisms in patients with rheumatoid arthritis in Koreans

Natural resistance-associated macrophage protein 1 (Nramp1) is a genetic locus associated with innate resistance or susceptibility of murine hosts to infection with intracellular pathogens such as Salmonella, Leishmania and Mycobacterium. The human homologue of the Nramp1 gene, designated NRAMP1, has been investigated as a candidate gene for genetic susceptibility to autoimmune diseases as well as infections. This study tries to determine whether NRAMP1 polymorphisms are associated with susceptibility to rheumatoid arthritis in Koreans. The nine NRAMP1 polymorphisms (1 microsatellite, 1 variation in 3' UTR, 5 silent substitution, 2 amino acid substitution) were typed by PCR-RFLP in 74 patients with rheumatoid arthritis (RA) and 53 healthy controls in Koreans. The distribution of allele and genotype frequencies were compared between patients and controls. Three NRAMP1 polymorphisms (823C/T, D543N and 1729+55del4) were significantly associated with RA. In addition, there were significant differences in the genotype frequencies for 823C/T, D543N and 1729+ 55del4 polymorphisms between RA patients and controls. Genotypes of A/A homozygote for D543N and TGTG deletion homozygote for 1729+55del4 were only detected in the patient group. These data indicate that genetic polymorphisms of NRAMP1 might be associated with the susceptibility to rheumatoid arthritis in Koreans.