Immunosuppressants in Oral Medicine: A Review

Immunologically mediated mucocutaneous diseases constitute a large group of oral mucosal disorders that compromise the quality of life of patients due to their chronicity. The treatment of these disorders should not only be directed to bring relief from symptoms but also towards treating the underlying immune dysregulation, prevent recurrences, and preserve organ integrity and function. These disorders are largely treated by immunosuppressants. Challenge in treating these disorders lies in existing comorbidities, frequent relapses or short disease-free intervals, and long-term use of medication and their complications. This review focusses on newer immunosuppressants and their role in oral mucosal disorders

Caffeine affects adventitious rooting and causes biochemical changes in the hypocotyl cuttings of mung bean (Phaseolus aureus Roxb.)

Caffeine (1,3,7-trimethylxanthine), a purine alkaloid found naturally in over 100 plant species, has recently been viewed as a safe chemical for management of pests including molluscs, slugs, snails, bacteria, and as a bird deterrent. It possesses phytotoxicity against plant species, yet the mechanism of action is lacking. A study was conducted to determine the effect of caffeine on the rooting of hypocotyl cuttings of mung bean (Phaseolus aureus) and the associated biochemical changes. At lower concentrations (<1,000 µM) of caffeine, though rooting potential was not affected, yet there was a significant decrease in the number of roots and root length. At 1,000 µM caffeine, there was a 68% decrease in the number of roots/primordia per cutting, whereas root length decreased by over 80%. However, no root formation occurred at 2,000 µM caffeine. Further investigations into the biochemical processes linked to root formation revealed that caffeine significantly affects protein content, activities of proteases, polyphenol oxidases (PPO) and total endogenous phenolic (EP) content, in the mung bean hypocotyls. A decrease in rooting potential was associated with a drastic reduction in protein content in the lower rooted portion, whereas the specific activity of proteases increased indicating that caffeine affects the protein metabolism. Activity of PPO decreased in response to caffeine, whereas EP content increased significantly indicating its non-utilization and thus less or no root formation. Respiratory ability of rooted tissue, as determined through TTC (2,3,5-triphenyl tetrazolium chloride) reduction, was impaired in response to caffeine indicating an adverse effect on the energy metabolism. The study concludes that caffeine interferes with the root development by impairing protein metabolism, affecting activity of PPO (and thus lignification), and EP content, which are the crucial steps for root formation