METHODOLOGICAL CARE IN THE EVALUATION OF THE LD50 AND OF THE NEUTRALIZATION OF THE LETHAL EFFECT OF Crotalus durissus terrificus VENOM BY THE PLANT Peschiera fuchsiaefolia (APOCYNACEAE)

Abstract

In the present study, we demonstrate that the volumes in which a given protein mass of Crotalus durissus terrificus venom or of a lyophilized stabilized aqueous extract (LSAE) of Peschiera fuchsiaefolia, an antivenom agent injected intramuscularly, have a decisive influence on the results. The LD50 of C. d. terrificus venom injected i.m. in a final volume of 200µl (2µl/g) (saline solution, 0.9% NaCl) was 180µg/100g rat body weight (p<0.05, 161 to 202µg/100g body weight) and the LD50 of the venom injected i.m. in a volume of 50µl (0.5µl/g) was 120µg/100g body weight (p<0.05, 107 to 134 µg/100g body weight). The reduction of the final volume injected i.m. also required a reduced mass of LSAE necessary to neutralize the lethal effect of C. d. terrificus venom. The dose of 60mg LSAE/100g rat body weight in a final volume of 200µl administered i.m. 20 seconds after venom injection, and that of 40mg LSAE/100g body weight/200µl mixed and incubated with the venom for 1 h at 25ºC before i.m. injection were able to neutralize the lethal activity of 2LD50. However, the LSAE doses that neutralized the 2LD50 were reduced to 20mg LSAE/100g body weight in a final volume of 50µl when administered i.m. 20 seconds after venom injection and to 2.5mg LSAE/100g body weight/50µl when mixed and incubated for 1 h at 25ºC with the venom before i.m. injection. The LD50 of C. d. terrificus venom and the doses of P. fuchsiaefolia LSAE that neutralized the venom lethal activity were, therefore, significantly lower when the final volume injected i.m. was reduced

Snake Venom Phospholipase A2 Inhibitors: Medicinal Chemistry and Therapeutic Potential

“…Recently, wedelolactone was assayed against Calloselasma rhodostoma venom, neutralizing the toxic effects of isolated PLA 2 s and the crude venom lethality [16,17,[87][88][89][90]. From Baccharis trimera (Asteraceae) a diterpenoid was isolated, neo-clerodane inhibitor of snake venom metalloproteases, with antiproteolytic and antihemorrhagic properties [91].…”

“…Several other plants with antiphopholipase A 2 and antivenom properties were described: (i) the root extract from Mimosa pudica neutralized myotoxins, toxic enzymes and lethality from Naja kaouthia venom; (ii) methanolic extracts of roots from Hemidesmus indicus and H. pluchea inhibited the hemorrhagic and lethal effects of Vipera ruselli venom; (iii) the methanolic extract from Eryngium creticum inhibited the hemolytic activity of Leiurus quinquestriatus http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Search&d b=pubmed&term=leiurus+quinquestriatus&tool=fuzzy&ot=Lei urus+quinquesteiartus> scorpion venom; (iv) decrease of the lethal effect of C. d. terrificus venom by the extract from Peschiera fuchsiaefolia was also reported; (v) the venoms from Naja nigricollis and Echis ocellatus had their neurotoxic and myotoxic activities inhibited by the methanolic extract from Parkia biglobosa bark; (vi) the methanolic extract from other Indian plants (Vitex negundo and Emblica officinalis) neutralized the hemorr-hagic, coagulant and inflammatory effects of Vipera russellii and Naja kaouthia venoms; (vii) preliminary studies showed the inhibitory activity of the extract from Marsypianthes chamaedrys against the clotting activity of B. jararaca venom; (ix) Musa paradisiaca, an important food all over the world, also showed antiophidian properties against PLA 2 , myotoxic, hemorrhagic and lethal activities of Crotalidae venoms; (x) inhibitory effects of the compound arturmerone isolated from Curcuma longa, able to neutralize the hemorrhagic activity of B. jararaca venom and the lethal effect of C. d. terrificus venom was also showed [88,[103][104][105][106][107][108][109][110][111] da Silva et al [99] isolated edunol, a pterocarpan from Harpalyce brasiliana, with antimyotoxic and antiproteolytic activities against B. jararacussu venom, besides expressive PLA 2 s inhibitory properties. Recently, rosmarinic acid, isolated from Cordia verbenacea, known as "erva baleeira" (Waler herb), was shown to neutralize the PLA 2 s BthTX-I and II from B. jararacussu snake venom [6,112] (Fig.…”

Les hibiscus, tradition et modernité

“…esculentus L. montre un pouvoir de protection contre le venin du serpent Bothrops jararaca[4].Utilisation courante et traditionnelleL'Hibiscus esculentus L. est une plante alimentaire importante : Elle est utilis6e en Afrique dans la r6alisation des soupes auxqueUes, en plus des apports nutritionnels, eUe donne << du corps >> (stabilise et 6paissit l'6mulsion huile/ eau). Elle est consomm6e comme 16gume, riche en fibre alimentaire (57 %) dans de nombreux pays (pays d'Am6rique du Sud comme le Br6sil, pays d'Afrique comme le Cameroun, en Asie comme en Chine).Les agents prot~olytiques et les substances allergisantes contenues dans les gousses immatures d'okra et dans les feuilles sont responsables de l~sions dermatologiques comme les allergies et irritations de contact.…”

Estudo da ação antiofídica do extrato das folhas e do suco de graviola (Annona muricata) no envenenamento por Lachesis muta rhombeata

“…Um número grande de plantas antiofídicas tem sido estudado na procura e caracterização de substâncias biologicamente ativas capazes de neutralizar diversos efeitos locais e sistêmicos provocados pelas peçonhas animais (MORS et al, 2000). Diversos autores relatam a ação antiofídica de plantas e substâncias isoladas como: ar-tumerone de Curcuma longa (FERREIRA et al, 1992), fração HI-RVIF de Salsaparrilha indicus (ALAM et al, 1994), wedelolactona, estigmasterol e sitosterol isolados da Eclipta prostrata (MELO et al, 1994, MARTZ, 1992, bredemeyrosídeo B isolado de Bredemeyera floribunda (DAROS et al, 1996), extrato aquoso de Peschiera fuchsiaefolia (BATINA, 1996;BATINA et al, 1997BATINA et al, e 2000 hoje reclassificada como Tabernaemontana catharinensis e Annona crassifora (WEINBERG et al, 1993) Na região da Mata Atlântica do Norte e Nordeste brasileiro, o suco da fruta e o extrato aquoso de folhas de gravioleira (Annona muricata) são frequentemente usados pela população local para tratar o envenenamento por mordida de surucucu (Lachesis muta rhombeata). -POLO et al, 1998).…”