Cranberry prevents the adhesion of bacteria: overview of relevant health benefits

Overview of Bacterial Adhesion The adherence of bacteria to cells or tissues in the body is the propagating step in infections. Bacterial surfaces contain several types of molecules that help them attach to cells, such as proteinaceous fimbriae or pili, flagella, lipopolysaccharides, and capsular polysaccharide molecules. When the bacterial structures find their complementary receptors on mammalian cells, the two bind tightly. In the case of urinary tract infections, fimbriae expressed by Escherichia coli (E. coli) must bind to receptors on uroepithelial cells. Compounds that prevent this adhesion represent an alternative therapy to the use of antibiotics, since the anti-adhesion molecules do not kill or impair the growth of the bacteria, yet they are able to prevent the infection from developing. A similar mechanism exists in gastric ulcers. In the case of a Helicobacter pylori infection, which can lead to the development of a gastroduodenal ulcer, bacteria must attach to human gastric mucosal cells for the infection to develop. A third bacterial infection that develops following adhesion of bacteria is related to periodontitis, an inflammatory disorder of tooth-supporting tissues. Gramnegative bacteria, such as Porphyromonas gingivalis can colonize teeth, gingival epithelial cells, and red blood cells, or interact with other oral bacteria and proteins in the mouth through receptors on their surfaces (1). In each of these three systems, cranberry compounds have been implicated in preventing the bacterial adhesion process, thus presenting a complementary or alternative methodology to prevent urinary tract infections (2, 3), H. pylori infections (4, 5), and periodontitis (1). We present a brief overview of the current knowledge of how cranberry is beneficial for these three systems.