Anti-Helicobacter pylori Activity and Gastroprotective Effects of Diacetylcurcumin and Four Metal Derivatives

<i>Helicobacter pylori</i> is the main etiological factor of gastritis, peptic ulcers, and gastric cancer. This bacterium's antibiotic resistance has led to a lower eradication rate; therefore, new drugs with anti-<i>H. pylori</i> activity are needed. Curcumin exhibits multiple biological activities, but it has low stability and poor bioavailability. To overcome these disadvantages, different metal complexes have been synthesized. The objective of this study was to determine the in vitro anti-<i>H. pylori</i> activity of diacetylcurcumin (DAC), DAC₂-Cu, DAC₂-Zn, DAC₂-Mn, and DAC₂-Mg by obtaining the minimum inhibitory concentration of bacterial growth, and to investigate some mechanisms by which they could affect the bacteria (urease and DNA gyrase activities). Moreover, their gastroprotective potential was assayed in an ethanol-induced gastric ulcer model in mice. The results showed that DAC₂-Cu and DAC₂-Zn have good anti-<i>H. pylori</i> activity, exhibit specific activity against this bacterium, inhibit the urease activity, and provide 70% gastroprotection at a dose of 200 mg/kg of body weight. In a subacute toxicity study in mice, DAC₂-Cu and DAC₂-Zn did not cause death or any deleterious symptoms, nor did they have a significant effect on serum and urine biochemical parameters compared to control mice. These compounds are promising candidates for use in <i>H. pylori</i> eradication schemes.