Gastroprotective mechanisms of Citrus lemon (Rutaceae) essential oil and its majority compounds limonene and β-pinene: Involvement of heat-shock protein-70, vasoactive intestinal peptide, glutathione, sulfhydryl compounds, nitric oxide and prostaglandin E

• Published in: Chemico-biological interactions 2011-01, Vol.189 (1-2), p.82-89
• Main Authors: Rozza, Ariane Leite, Moraes, Thiago de Mello, Kushima, Hélio, Tanimoto, Alexandre, Marques, Márcia Ortiz Mayo, Bauab, Taís Maria, Hiruma-Lima, Clélia Akiko, Pellizzon, Cláudia Helena
• Format: Article
• Language: English
• Subjects: Animals; bark; beta-pinene; Bridged Bicyclo Compounds - pharmacology; Citrus; Citrus - chemistry; Cyclohexenes - pharmacology; Dinoprostone - metabolism; Disease Models, Animal; Drug Synergism; essential oils; ethanol; glutathione; Glutathione - metabolism; heat stress; Helicobacter Infections - drug therapy; Helicobacter Infections - metabolism; Helicobacter Infections - microbiology; Helicobacter pylori - drug effects; HSP70 Heat-Shock Proteins - metabolism; Immunohistochemistry; indomethacin; lemons; Male; mechanism of action; Microbial Sensitivity Tests; minimum inhibitory concentration; Monoterpenes - pharmacology; mucus; nitric oxide; Nitric Oxide - metabolism; Plant Oils - pharmacology; prostaglandins; Protective Agents - pharmacology; Rats; Rats, Wistar; secretion; Stomach Ulcer - metabolism; Stomach Ulcer - microbiology; Stomach Ulcer - prevention & control; stomach ulcers; Sulfhydryl Compounds - metabolism; Terpenes - pharmacology; vasoactive intestinal peptide; Vasoactive Intestinal Peptide - metabolism
• ISSN: 0009-2797; 1872-7786
• DOI: 10.1016/j.cbi.2010.09.031

Citrus lemon (CL) belongs to Rutaceae family and is popularly known in Brazil as limão siciliano. The phytochemical analysis of CL fruit bark essential oil showed two majority components, limonene (LIM) and β-pinene (PIN). This study aimed to evaluate the gastroprotective mechanism of action from CL, LIM and PIN in ethanol- and indomethacin-induced gastric ulcers and its in vitro anti-Helicobacter pylori activity. After ethanol-induced gastric ulcer, the ulcer area was measured and the stomachs were destined to histology (HE and PAS), immunohistochemistry for HSP-70 and VIP and glutathione (GSH) measurement. The involvement of nitric oxide (NO) and sulfhydryl (SH) compounds was determined. The ulcer area for indomethacin-induced gastric ulcers was measured. PGE₂ concentration was biochemically measured. The minimum inhibitory concentration (MIC) against H. pylori was determined in vitro. In ethanol model, CL and LIM demonstrated 100% of gastroprotection, while PIN did not exert effective gastroprotection (53.26%). In the indomethacin model, CL and LIM offered effective gastroprotection but PIN did not show gastroprotective effect. The gastric ulcer area of rats pretreated with NO-synthase inhibitor or SH-blocker was decreased in comparison to the control group. The MIC obtained for CL was 125μg/mL, for LIM was 75μg/mL and for PIN was 500μg/mL. The gastroprotective effect of CL and LIM was involved with increasing in mucus secretion, HSP-70 and VIP, but not with GSH, NO or SH compounds. CL gastroprotective mechanism is involved with PGE₂. PIN did not present gastroprotective activity.