Carbon nanotubes provide longer lasting gastroprotective effects for anandamide in stress-induced gastric ulcer in rat

Introduction: Anandamide (AEA) has shown a wide spectrum of pharmacological activities including the effects against the peptic ulcer, meanwhile, the poor solubility or short half-life may negatively affect the effectiveness of this valuable cannabinoid. Based on the superior properties of carbon nanotubes (CNTs) for controlled drug delivery, we aimed to prepare AEA-CNTs complex and evaluate its therapeutic potential in an experimental model of gastric ulcer. Methods: Amino-functionalized multi-walled CNTs-AEA (MWCNTs-AEA) complex was prepared using COOH-MWCNTs and then characterized by Fourier transform infrared spectroscopy and transmission electron microscopy. Gastric ulcer was induced by water immersion and restrain stress (WRS) for 3.5 and 6 h in rats and the gastric lesion and oxidative stress were evaluated. Results: AEA at higher doses reduced the gastric ulcer area and malondialdehyde content and elevated glutathione level and superoxide dismutase and catalase activities after 3.5-h WRS but it was ineffective after 6-h WRS. MWCNTs-AEA complex showed therapeutic effects after both 3.5- and 6-h WRS. Conclusion: Aminated MWCNTs are suitable carriers for AEA as they provide longer lasting effects for this cannabinoid. The antioxidant mechanism may be involved in the gastroprotective effects of MWCNTs-AEA complex.