Efeito gastroprotetor das partes aéreas do extrato aquoso da Mesosphaerum pectinatum (L.) Kuntze em camundongos

Abstract

Gastric ulcer is characterized by lesions in the gastric mucosa. The drugs used for its treatment are not entirely effective and their prolonged use can cause serious adverse reactions. Plants represent an effective alternative for the treatment of various diseases, and Mesosphaerum pectinatum (L.) Kuntze, whic is well known in the Brazilian Northeast as "canudinho" or "sambacaitá," is popularly used in the form of teas for pain relief, wound healing, inflammation, and gastric problems. Thus, the present study aimed to investigate the gastroprotective action of the aqueous extract of M. pectinatum (EAMP) in mice and the possible mechanisms involved in gastroprotection. After approval from the UFS Animal Research Ethics Committee (No. 4058270622), male Swiss mice were submitted to the model of ethanol-induced ulcer (ethanol at 60%/HCl at 0.3 mol/L) to assess the gastroprotective effect of EAMP (25, 50, and 100 mg/kg, orally), as well as to evaluate the activity of myeloperoxidase and concentrations of tumor necrosis factor (TNF)-α, and interleukins (IL)-1β and 6 in gastric tissue. Additionally, the involvement of non-protein sulfhydryl compounds (NP-SH), nitricoxide (NO), and ATP-sensitive K+ channels (KATP) was investigated. Pretreatment with EAMP (25, 50, and 100 mg/kg) significantly reduced the area of gastric lesions induced by acidified ethanol, as well as reducing the activity of myeloperoxidase in gastric tissue. Furthermore, the induction with acidified ethanol did not alter the concentration of TNF-α and IL-1β but increased the concentration of IL-6 (p<0.001) compared to non-ulcerated tissue. Pretreatment with EAMP (50 mg/kg) decreased the concentration of IL-6 in gastric tissue (p<0.001). Pretreatment with the NP-SH blocker (N-ethylmaleimide, 10 mg/kg, i.p.) inhibited the gastroprotective response caused by EAMP (50 mg/kg; p<0.001), but this did not occur with pretreatments with a KATP blocker (glibenclamide, 10 mg/kg, i.p.) and an inhibitor of nitric oxide synthases (L-NAME, 70 mg/kg). These results prove that EAMP exerts gastroprotective action in mice by reducing inflammatory response and involving NP-SH. Additional experiments should contribute to a better understanding of the actions of this extract.