The effects of baicalein on gastric mucosal ulcerations in mice: Protective pathways and anti-secretory mechanisms

Chem Biol Interact. 2016 Dec 25:260:33-41. doi: 10.1016/j.cbi.2016.10.016. Epub 2016 Oct 22.

Abstract

Many flavonoids have been shown to present good results for the treatment of gastric ulcers. Baicalein, a bioactive flavonoid derived from the Scutellaria baicalensis Georgi root, possesses several biological effects, such as anti-inflammatory and antioxidant. This study was conducted to assess the gastroprotective properties of baicalein. Anti-ulcerogenic assay was performed using the protocol of ulcer induced by ethanol/HCl in mice; then, the role of presynaptic α2-receptors, sulfhydryl (SH) compounds, nitric oxide (NO), prostaglandin (PG) and ATP-sensitive K+ (KATP) channels in gastroprotection of baicalein was investigated. The levels of reduced glutathione (GSH) and the myeloperoxidase (MPO) activity were measured in the gastric mucosa. Parameters of gastric secretion (volume, [H+] and pH) were determined with or without the presence of the secretagogue agent histamine, as well as mucus in gastric contents, by the pylorus ligation model. In vitro H+,K+-ATPase activity was also determined. Baicalein (10, 30 and 100 mg/kg) exhibited a dose related gastroprotective effect (P < 0.001) against acidified ethanol-induced lesions. The intraperitoneal treatment of mice with a α2-adrenoreceptor antagonist (yohimbine; 2 mg/kg), a SH compounds blocker (N-ethylmaleimide, NEM; 10 mg/kg), a non-selective inhibitor of NO synthase (Nw-nitro-L-arginine methyl ester hydrochloride, L-NAME; 10 mg/kg), a non-selective inhibitor of cyclo-oxygenase (indomethacin; 10 mg/kg) or a KATP channel blocker (glibenclamide; 10 mg/kg) was able to reverse (P < 0.001) the gastroprotective response caused by baicalein (30 mg/kg). Baicalein (30 mg/kg; P < 0.05) was able to increase GSH levels and decreasing MPO activity. The intraduodenal treatment with baicalein (30 and 100 mg/kg) significantly increased (P < 0.05) the gastric mucus secretion. Additionally, the treatment with baicalein reduced (30 and 100 mg/kg; P < 0.05) the secretion volume and total acid secretion, and also increased (10, 30 and 100 mg/kg; P < 0.001) the pH value, after pylorus ligature. Baicalein (30 mg/kg) was also effective in inhibiting the effects of histamine on gastric secretion (volume, [H+] and pH; P < 0.001). Baicalein at 10 and 30 μg/mL showed anti-H+,K+-ATPase activity. In conclusion, the present results provide convincing evidence that baicalein could be used as a cytoprotective (preventive effect) and anti-ulcerogenic (anti-secretory effect) agent in the gastric ulcers.

Keywords: Baicalein; Flavonoids; Gastric ulcer; Gastroprotection.

MeSH terms

  • Animals
  • Ethanol
  • Female
  • Flavanones / administration & dosage
  • Flavanones / pharmacology
  • Flavanones / therapeutic use*
  • Gastric Juice / metabolism
  • Gastric Mucosa / drug effects
  • Gastric Mucosa / metabolism*
  • Gastric Mucosa / pathology*
  • Glutathione / metabolism
  • H(+)-K(+)-Exchanging ATPase / metabolism
  • Hydrochloric Acid
  • KATP Channels / metabolism
  • Male
  • Mice
  • Peroxidase / metabolism
  • Prostaglandins / metabolism
  • Protective Agents / administration & dosage
  • Protective Agents / pharmacology
  • Protective Agents / therapeutic use*
  • Stomach / drug effects
  • Stomach Ulcer / chemically induced
  • Stomach Ulcer / drug therapy
  • Stomach Ulcer / pathology

Substances

  • Flavanones
  • KATP Channels
  • Prostaglandins
  • Protective Agents
  • Ethanol
  • baicalein
  • Peroxidase
  • H(+)-K(+)-Exchanging ATPase
  • Glutathione
  • Hydrochloric Acid