In vitro antiophidian mechanisms of Hypericum brasiliense choisy standardized extract: quercetin-dependent neuroprotection.
The neuroprotection induced by Hypericum brasiliense Choisy extract (HBE) and its main active polyphenol compound quercetin, against Crotalus durissus terrificus (Cdt) venom and crotoxin and crotamine, was enquired at both central and peripheral mammal nervous system. Cdt venom (10 μg/mL) or crotoxin (1 μg/mL) incubated at mouse phrenic nerve-diaphragm preparation (PND) induced an irreversible and complete neuromuscular blockade, respectively. Crotamine (1 μg/mL) only induced an increase of muscle strength at PND preparations. At mouse brain slices, Cdt venom (1, 5, and 10 μg/mL) decreased cell viability. HBE (100 μg/mL) inhibited significantly the facilitatory action of crotamine (1 μg/mL) and was partially active against the neuromuscular blockade of crotoxin (1 μg/mL) (data not shown). Quercetin (10 μg/mL) mimicked the neuromuscular protection of HBE (100 μg/mL), by inhibiting almost completely the neurotoxic effect induced by crotoxin (1 μg/mL) and crotamine (1 μg/mL). HBE (100 μg/mL) and quercetin (10 μg/mL) also increased cell viability in mice brain slices. Quercetin (10 μg/mL) was more effective than HBE (100 μg/mL) in counteracting the cell lysis induced by Cdt venom (1 and 10 μg/mL, resp.). These results and a further phytochemical and toxicological investigations could open new perspectives towards therapeutic use of Hypericum brasiliense standardized extract and quercetin, especially to counteract the neurotoxic effect induced by snake neurotoxic venoms.
CIPBIOTEC, Federal University of Pampa, (UNIPAMPA), Campus São Gabriel, 97300-000 São Gabriel, RS, Brazil.
Cháriston André
CA
Dal Belo
CIPBIOTEC, Federal University of Pampa, (UNIPAMPA), Campus São Gabriel, 97300-000 São Gabriel, RS, Brazil.
Ana Paula de Bairros
AP
Lucho
CIPBIOTEC, Federal University of Pampa, (UNIPAMPA), Campus São Gabriel, 97300-000 São Gabriel, RS, Brazil.
Lúcia
L
Vinadé
Laboratory of Natural Products Technology, Federal University Fluminense, Faculty of Pharmacy, 24241-002 Niterói, RJ, Brazil.
Leandro
L
Rocha
Federal Institute of Espírito Santo, Campus Vila Velha, 29106-010 Vila Velha, Espírito Santo, Brazil.
Hildegardo
H
Seibert França
LAQUIP, Department of Biochemistry, Institute of Biology, State University of Campinas (UNICAMP), P.O. Box 6109, 13083-970 Campinas, SP, Brazil.
Sérgio
S
Marangoni
Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), P.O. Box 6111, 13083-970 Campinas, SP, Brazil.
Léa
L
Rodrigues-Simioni
D000818:Animals; D001921:Brain / Q000166:cytology / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003435:Crotalid Venoms / Q000633:toxicity; D003439:Crotoxin / Q000633:toxicity; D003964:Diaphragm / Q000187:drug effects; D006801:Humans; D020902:Hypericum / Q000737:chemistry; D051379:Mice; D019148:Neuromuscular Blockade; D018696:Neuroprotective Agents / Q000008:administration & dosage*; D010791:Phrenic Nerve / Q000187:drug effects* / Q000503:physiopathology; D010936:Plant Extracts / Q000008:administration & dosage* / Q000737:chemistry; D011794:Quercetin / Q000008:administration & dosage
D003435:Crotalid Venoms; D018696:Neuroprotective Agents; D010936:Plant Extracts; D003439:Crotoxin; D011794:Quercetin; C010563:crotamine