Ulcer healing and mechanism(s) of action involved in the gastroprotective activity of fractions obtained from Syngonanthus arthrotrichus and Syngonanthus bisulcatus.
BACKGROUND
Syngonanthus arthrotrichus and Syngonanthus bisulcatus, currently known for Comanthera aciphylla (Bong.) L.R.Parra & Giul. and Comanthera bisulcata (Koern.) L.R. Parra & Giul, popularly known in Brazil as "sempre-vivas," are plants from the family Eriocaulaceae. They are found in the states of Minas Gerais and Bahia. The species are known to be rich in flavonoids to which their gastroprotective activity has been attributed. In this research, experimental protocols were performed to elucidate the associated mechanisms of action.


METHODS
The activity was evaluated using induced gastric ulcer models (acetic acid and ethanol-induced gastric lesions in NEM or L-NAME pre-treated mice, and by ischemia/reperfusion). Antioxidant enzymes, serum somatostatin, and gastrin were also evaluated.


RESULTS
In chronic gastric ulcers, a single daily oral dose of Sa-FRF or Sb-FRF (100 mg/kg body wt.) for 14 consecutive days accelerated ulcer healing to an extent similar to that seen with an equal dose of cimetidine. The pre-treatment of mice with NEM (N-ethylmaleimide) or L-NAME (N-nitro-L-arginine) abolished the protective activity of Sa-FRF, Sa-FDF, Sb-FDF and Sb-FRF or Sa-FRF and Sb-FRF, respectively, which indicates that antioxidant compounds and nitric oxide synthase activity are involved in the gastroprotective. Sa-FRF and Sb-FRF (100 mg/kg p.o) protected the gastric mucosa against ulceration that was induced by ischemia/reperfusion (72 and 76 %, respectively). It also decreased lipid peroxidation and restored total thiols in the gastric wall of mice that had been treated with ethanol. When administered to rats submitted to ethanol-induced gastric lesions, Sa-FRF and Sb-FRF (100 mg/kg, p.o.) increased the somatostatin serum levels, while the gastrin serum levels were proportionally decreased.


CONCLUSIONS
The results indicate significant healing effects and gastroprotective activity for the Sa-FRF and Sb-FRF, which probably involves the participation of SH groups, nitric oxide (NO), the antioxidant system, somatostatin, and gastrin. All are integral parts of the gastrointestinal mucosa's cytoprotective mechanisms against aggressive factors.
Departamento de Ciências Farmacêuticas, Centro de Ciências da Saúde, Laboratório de Farmacologia do Trato Gastrintestinal, Universidade Federal da Paraíba (UFPB), João Pessoa, PB, Brazil. leoniab@uol.com.br.|Departamento de Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil. leoniab@uol.com.br.
Leônia Maria
LM
Batista
Departamento de Ciências Farmacêuticas, Centro de Ciências da Saúde, Laboratório de Farmacologia do Trato Gastrintestinal, Universidade Federal da Paraíba (UFPB), João Pessoa, PB, Brazil. gedsonfarm@hotmail.com.
Gedson Rodrigues De Morais
GR
Lima
Departamento de Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil. anabia5@yahoo.com.br.
Ana Beatriz Albino
AB
De Almeida
Departamento de Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil. lumagri@hotmail.com.
Luciana De Pietro
Lde P
Magri
Departamento de Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil. tamaracalvo@yahoo.com.br.
Tamara Regina
TR
Calvo
Departamento de Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil. domcarecone@yahoo.com.br.
Anderson Luiz
AL
Ferreira
Departamento de Morfologia, Instituto de Biociências, Universidade Estadual Paulista, Botucatu, SP, Brazil. claudia.pellizzon@gmail.com.
Cláudia Helena
CH
Pellizzon
Departamento de Fisiologia, Instituto de Biociências, Universidade Estadual Paulista, Botucatu, SP, Brazil. hiruma@ibb.unesp.br.
Clélia Akiko
CA
Hiruma-Lima
Departamento de Fisiologia, Instituto de Biociências, Universidade Estadual Paulista, Botucatu, SP, Brazil. vilegasw@iq.unesp.br.
Wagner
W
Vilegas
Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil. ptsano@usp.br.
Paulo Takeo
PT
Sano
Departamento de Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil. abrito@unicamp.br.
Alba Regina Monteiro Souza
AR
Brito
D000818:Animals; D000897:Anti-Ulcer Agents / Q000008:administration & dosage*; D039262:Eriocaulaceae / Q000737:chemistry*; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D008297:Male; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D010936:Plant Extracts / Q000008:administration & dosage*; D020011:Protective Agents / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar; D013276:Stomach Ulcer / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D014945:Wound Healing / Q000187:drug effects
D000897:Anti-Ulcer Agents; D010936:Plant Extracts; D020011:Protective Agents; D009569:Nitric Oxide